BEGIN:VCALENDAR VERSION:2.0 PRODID:-//SF Bay Conservation & Development - ECPv6.16.2//NONSGML v1.0//EN CALSCALE:GREGORIAN METHOD:PUBLISH X-WR-CALNAME:SF Bay Conservation & Development X-ORIGINAL-URL:https://www.bcdc.ca.gov X-WR-CALDESC:Events for SF Bay Conservation & Development REFRESH-INTERVAL;VALUE=DURATION:PT1H X-Robots-Tag:noindex X-PUBLISHED-TTL:PT1H BEGIN:VTIMEZONE TZID:America/Los_Angeles BEGIN:DAYLIGHT TZOFFSETFROM:-0800 TZOFFSETTO:-0700 TZNAME:PDT DTSTART:20230312T100000 END:DAYLIGHT BEGIN:STANDARD TZOFFSETFROM:-0700 TZOFFSETTO:-0800 TZNAME:PST DTSTART:20231105T090000 END:STANDARD BEGIN:DAYLIGHT TZOFFSETFROM:-0800 TZOFFSETTO:-0700 TZNAME:PDT DTSTART:20240310T100000 END:DAYLIGHT BEGIN:STANDARD TZOFFSETFROM:-0700 TZOFFSETTO:-0800 TZNAME:PST DTSTART:20241103T090000 END:STANDARD BEGIN:DAYLIGHT TZOFFSETFROM:-0800 TZOFFSETTO:-0700 TZNAME:PDT DTSTART:20250309T100000 END:DAYLIGHT BEGIN:STANDARD TZOFFSETFROM:-0700 TZOFFSETTO:-0800 TZNAME:PST DTSTART:20251102T090000 END:STANDARD BEGIN:DAYLIGHT TZOFFSETFROM:-0800 TZOFFSETTO:-0700 TZNAME:PDT DTSTART:20260308T100000 END:DAYLIGHT BEGIN:STANDARD TZOFFSETFROM:-0700 TZOFFSETTO:-0800 TZNAME:PST DTSTART:20261101T090000 END:STANDARD END:VTIMEZONE BEGIN:VEVENT DTSTART;TZID=America/Los_Angeles:20251031T100000 DTEND;TZID=America/Los_Angeles:20251031T120000 DTSTAMP:20260624T062646 CREATED:20251020T213735Z LAST-MODIFIED:20251125T202027Z UID:10000307-1761904800-1761912000@www.bcdc.ca.gov SUMMARY:October 31\, 2025 Sand Studies Commissioner Working Group DESCRIPTION:Join the Meeting Via Zoom:https://bcdc-ca-gov.zoom.us/j/83404163683?pwd=CP9mICcU8LCInW9sS2cdaHJLaOrOil.1  \nMeeting ID:834 0416 3683 \nPasscode: 253303 \nTeleconference Numbers:Dial by your location• +1 408-961-3929 US• +1 408-961-3927 US• +1 408-961-3928 US• 1 855-758-1310 US Toll-free \nIf you call in by phone:Press *6 to unmute your phonePress *9 to raise/lower your hand \n \n \n \n \n Agenda\n 1. Welcome and IntroductionsPatricia Showalter (Chair) will open the meeting and conduct Commissioner roll-call. Brenda Goeden will give a brief overview of the agenda \n2. Understanding Sand Mining Process\, Transport\, and UseRepresentatives from the sand mining industry will respond to the Commissioner’s questions about where and how minded sand is used\, whether it stays in the Bay Area\, and other information about the sand mining operations in the Bay Area. (Brenda Goeden) [415/352-3623; brenda.goeden@bcdc.ca.gov] Sand Miners Presentation \n3. Commission Laws\, Policies\, and AuthorityThe Commissioners will receive a briefing from staff on laws and policies that are applicable to future sand mining permit applications. Staff will provide the briefing and Commissioners will have the opportunity to ask questions and discuss policy considerations.(Brenda Goeden) [415/352-3623; brenda.goeden@bcdc.ca.gov] Staff Presentation \n4. Sand Studies Commissioner Working Group Accomplishments and Next StepsAs this is the last Sand Studies Commissioner Working Group\, Commissioner Showalter and staff will share what the Working Group has accomplished over the past two years and describe the anticipated next steps for the Commission on this issue.(Brenda Goeden) [415/352-3623; brenda.goeden@bcdc.ca.gov] Staff Presentation \n5. General Public Comment PeriodPublic Comment LetterPublic Comment Presentation \n6. Adjournment \n \n \n \n \n \n Recording & Transcript\n \nTranscript \n \n \n \n \n \n Learn How to Participate\n Bagley-Keene Open Meeting Act\nAs a state agency\, the Commission is governed by the Bagley-Keene Open Meeting Act which requires the Commission to: (1) publish an agenda at least ten days in advance of any meeting; and (2) describe specifically in that agenda the items to be transacted or discussed. Public notices of Commission meetings and staff reports (as applicable) dealing with matters on the meeting agendas can be found on BCDC’s website. Simply access Commission Meetings under the “Public Meetings” tab on the website and select the date of the meeting. \nHow to Provide Comments and Comment Time Limits\nPursuant to state law\, the Commission is currently conducting its public meetings in a “hybrid” fashion. Each meeting notice will specify (1) where the meeting is being primarily held physically\, (2) all teleconference locations\, which will be publicly-accessible\, and (3) the ZOOM virtual meeting link. If you would like to comment at the beginning of the meeting or on an item scheduled for public discussion\, you may do so in one of three ways: (1) being present at the primary physical or a teleconference meeting location; (2) emailing comments in advance to public comment until 10 a.m. on the day of the meeting; and (3) participating via ZOOM during the meeting. \nIf you plan to participate through ZOOM\, please use your ZOOM-enabled device and click on the “raise your hand” button\, and then wait to speak until called upon. If you are using a telephone to call into the meeting\, select *6 to unmute your phone and you will then be able to speak. We ask that everyone use the mute button when not speaking. It is also important that you not put your phone on hold. Each speaker may be limited to a maximum of three minutes or less at the discretion of the Chair during the public comment period depending on the volume of persons intending to provide public comment. Any speakers who exceed the time limits or interfere with the meeting may be muted by the Chair. It is strongly recommended that public comments be submitted in writing so they can be distributed to all Commission members in advance of the meeting for review. You are encouraged to submit written comments of any length and detailed information to the staff prior to the meeting at the email address above\, which will be distributed to the Commission members. \nQuestions and Staff Reports\nIf you have any questions concerning an item on the agenda\, would like to receive notice of future hearings\, or access staff reports related to the item\, please contact the staff member whose name\, email address and direct phone number are indicated in parenthesis at the end of the agenda item. \nCampaign Contributions\nState law requires Commissioners to disqualify themselves from voting on any matter if they have received a campaign contribution from an interested party within the past 12 months. If you intend to speak on any hearing item\, please indicate in your testimony if you have made campaign contributions in excess of $250 to any Commissioner within the last year\, and if so\, to which Commissioner(s) you have contributed. Other legal requirements govern contributions by applicants and other interested parties and establish criteria for Commissioner conflicts of interest. Please consult with the staff counsel if you have any questions about the rules that pertain to campaign contributions or conflicts of interest. \nAccess to Meetings\nMeetings are physically held in venues that are accessible to persons with disabilities. If you require special assistance or have technical questions\, please contact staff at least three days prior to the meeting via email. We will attempt to make the virtual meeting accessible via ZOOM accessibility capabilities\, as well. URL:https://www.bcdc.ca.gov/event/october-31-2025-sand-studies-commissioner-working-group/ CATEGORIES:Sand Studies Commissioner Working Group END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/Los_Angeles:20250806T103000 DTEND;TZID=America/Los_Angeles:20250806T123000 DTSTAMP:20260624T062646 CREATED:20250717T195646Z LAST-MODIFIED:20251125T201042Z UID:10000300-1754476200-1754483400@www.bcdc.ca.gov SUMMARY:August 6\, 2025 Sand Studies Commissioner Working Group DESCRIPTION:Join the Meeting Via Zoom:https://bcdc-ca-gov.zoom.us/j/83056327976?pwd=XFMIZcmOItb0xAf4iajZ1Oww3O7zSA.1  \nMeeting ID830 5632 7976Passcode: 253303 \nTeleconference Numbers(214) 765-0479 US Toll;Conference Code: 900680(888) 278-0296 US Toll-FreeConference Code: 900680 \nIf you call in by phone:Press *6 to unmute your phonePress *9 to raise/lower your hand \n \n \n \n \n Agenda\n 1. Welcome and IntroductionsPatricia Showalter (Chair) will open the meeting and conduct Commissioner roll-call. Brenda Goeden will give a brief overview of the agenda \n2. Sand Mining\, Water and Sediment Quality Brenda Goeden will present information from studies analyzing the potential sediment contaminants associated with sand shoals and water quality associated with disposing water from mining operations in the Bay. (Brenda Goeden) [415/352-3623; brenda.goeden@bcdc.ca.gov] \n3. Ecological Connections in Central San Francisco Bay – Implications for Sand MiningThe Commissioners will receive a briefing on seabird foraging in Central San Francisco Bay presented by Dr. Julie Thayer of the Farallon Institute and potential impacts from human activities in the area. The Commission will discuss the implications of disturbances to this habitat type within the Bay.(Brenda Goeden) [415/352-3623; brenda.goeden@bcdc.ca.gov] \n4. General Public Comment Period \n5. Adjournment \n \n \n \n \n \n Recording & Transcript\n \n \n \n \n \n \n Learn How to Participate\n Bagley-Keene Open Meeting Act\nAs a state agency\, the Commission is governed by the Bagley-Keene Open Meeting Act which requires the Commission to: (1) publish an agenda at least ten days in advance of any meeting; and (2) describe specifically in that agenda the items to be transacted or discussed. Public notices of Commission meetings and staff reports (as applicable) dealing with matters on the meeting agendas can be found on BCDC’s website. Simply access Commission Meetings under the “Public Meetings” tab on the website and select the date of the meeting. \nHow to Provide Comments and Comment Time Limits\nPursuant to state law\, the Commission is currently conducting its public meetings in a “hybrid” fashion. Each meeting notice will specify (1) where the meeting is being primarily held physically\, (2) all teleconference locations\, which will be publicly-accessible\, and (3) the ZOOM virtual meeting link. If you would like to comment at the beginning of the meeting or on an item scheduled for public discussion\, you may do so in one of three ways: (1) being present at the primary physical or a teleconference meeting location; (2) emailing comments in advance to public comment until 10 a.m. on the day of the meeting; and (3) participating via ZOOM during the meeting. \nIf you plan to participate through ZOOM\, please use your ZOOM-enabled device and click on the “raise your hand” button\, and then wait to speak until called upon. If you are using a telephone to call into the meeting\, select *6 to unmute your phone and you will then be able to speak. We ask that everyone use the mute button when not speaking. It is also important that you not put your phone on hold. Each speaker may be limited to a maximum of three minutes or less at the discretion of the Chair during the public comment period depending on the volume of persons intending to provide public comment. Any speakers who exceed the time limits or interfere with the meeting may be muted by the Chair. It is strongly recommended that public comments be submitted in writing so they can be distributed to all Commission members in advance of the meeting for review. You are encouraged to submit written comments of any length and detailed information to the staff prior to the meeting at the email address above\, which will be distributed to the Commission members. \nQuestions and Staff Reports\nIf you have any questions concerning an item on the agenda\, would like to receive notice of future hearings\, or access staff reports related to the item\, please contact the staff member whose name\, email address and direct phone number are indicated in parenthesis at the end of the agenda item. \nCampaign Contributions\nState law requires Commissioners to disqualify themselves from voting on any matter if they have received a campaign contribution from an interested party within the past 12 months. If you intend to speak on any hearing item\, please indicate in your testimony if you have made campaign contributions in excess of $250 to any Commissioner within the last year\, and if so\, to which Commissioner(s) you have contributed. Other legal requirements govern contributions by applicants and other interested parties and establish criteria for Commissioner conflicts of interest. Please consult with the staff counsel if you have any questions about the rules that pertain to campaign contributions or conflicts of interest. \nAccess to Meetings\nMeetings are physically held in venues that are accessible to persons with disabilities. If you require special assistance or have technical questions\, please contact staff at least three days prior to the meeting via email. We will attempt to make the virtual meeting accessible via ZOOM accessibility capabilities\, as well. URL:https://www.bcdc.ca.gov/event/august-06-2025-sand-studies-commissioner-working-group/ CATEGORIES:Sand Studies Commissioner Working Group END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/Los_Angeles:20250521T100000 DTEND;TZID=America/Los_Angeles:20250521T120000 DTSTAMP:20260624T062646 CREATED:20250513T184613Z LAST-MODIFIED:20251125T200900Z UID:10000278-1747821600-1747828800@www.bcdc.ca.gov SUMMARY:May 21\, 2025 Sand Studies Commissioner Working Group DESCRIPTION:Join the Meeting Via Zoom:https://bcdc-ca-gov.zoom.us/j/88663722653?pwd=NmPBcEW2IMvYa2a0uwaPNjaWQ2Ev7s.1 \nMeeting ID886 6372 2653Passcode: 597125 \nTeleconference Numbers(214) 765-0479 US Toll;Conference Code: 900680(888) 278-0296 US Toll-FreeConference Code: 900680 \nIf you call in by phone:Press *6 to unmute your phonePress *9 to raise/lower your hand \n \n \n \n \n Agenda\n \nWelcome and IntroductionsPatricia Showalter (Chair) will open the meeting and conduct Commissioner roll-call.\nMining and Benthic Ecology 101Jaime Lopez will present a brief overview of the sand environment\, benthic community and function\, and wildlife foraging to provide context for the Commission and public. (Jaime Lopez) [415/352-3648; jaime.lopez@bcdc.ca.gov] Staff Presentation\n2009 Applied Marine Sciences Benthic StudyApplied Marine Sciences Senior Oceanographer\, Jay Johnson\, will present the findings from the “Benthic Survey of Commercial Aggregate Mining Leases in Central San Francisco Bay and Western Delta.” This study was conducted as part of the State Lands Commission Environmental Impact Report on mining in San Francisco Bay. The Commission Working Group members and the public will have an opportunity to discuss the study and its findings.(Brenda Goeden) [415/352-3623; brenda.goeden@bcdc.ca.gov] Applied Marine Sciences Presentation\nNewFields Benthic StudyNewfields Senior Scientist\, Tim Hammermeister\, will present the findings from the Benthic Assessment of Sand Mining in Point Knox Shoal (Central San Francisco Bay) and Suisun Bays (2016\, and 2018) study conducted as a requirement of the Commission permits. The Commission Working Group members and the public will have an opportunity to discuss the study and its findings.(Brenda Goeden) [415/352-3623; brenda.goeden@bcdc.ca.gov] NewFields Presentation\nCommission Discussion\nGeneral Public Comment Period\nAdjournment\n\n \n \n \n \n \n Additional Materials\n Benthic Survey of Commercial Aggregate Mining Areas in San Francisco Bay & Western Delta (AMS 2009)Benthic Assessment of Sand Mining in Central San Francisco Bay and Suisun Bays (NewFields 2018)Benthic Assessment of Sand Mining Final Memo (NewFields 2020)Sand Mining Industry Comment Letter on Benthic Studies \n \n \n \n \n \n Recording & Transcript\n \n\nTranscript\n\nbgoeden: It’s like they’ve got 14.bgoeden: Just gonna keep it. Many people. \nbgoeden: Good morning. Everyone. \nPat Showalter: Hello! \nErika Guerra: Good morning! \nPat Showalter: Glad you could all make it. \nPat Showalter: Okay. Well\, it’s always good to start right on time. \nPat Showalter: I’m Pat Showalter\, and I’m the chair of this committee. And I want to. \nPat Showalter: just start off by thanking everyone who has contributed science to this. This is a very valuable exercise for us to hear about the science that’s happened\, and and ask questions and understand it better. So I think it’s really valuable for Bcdc’s process. And I appreciate that. \nPat Showalter: So we’ll start off with. Oh\, the other thing I wanted to mention is that we have. We have several. We have a couple presentations\, and we’ll be taking public comment after each presentation\, and and we’ll give the miners an opportunity to to talk about each study and share their perspective. So with that I think we can move on to roll\, call. \nKathryn Riley\, BCDC: Commissioner\, Gunther. \nAndrew Gunther: Here. \nKathryn Riley\, BCDC: Chair. Show Walter. \nPat Showalter: Here. \nKathryn Riley\, BCDC: We have 2 out of 3 commissioners present. \nPat Showalter: Okay. \nPat Showalter: All right. \nbgoeden: It looks like we have 24 participants. At the moment pat. \nPat Showalter: Okay. \nPat Showalter: all right. Great. Well\, thank you all for being here. And we’re going to start with benthic ecology\, 101 with Jaime Lopez and \nPat Showalter: He will present this background. Information kind of as a \nPat Showalter: as a refresher for all of us\, or some of us may be \nPat Showalter: won’t be as much of a refresher as others\, and but to pull it all together. And\, Jaime\, are you available. \nJaime Lopez | BCDC: Yeah. \nJaime Lopez | BCDC: Can you guys hear me? I’m here. \nPat Showalter: We can. Yes\, all right. \nJaime Lopez | BCDC: Let me get this ready to go. \nJaime Lopez | BCDC: since we’re on. Zoom\, it’s a little bit different. \nJaime Lopez | BCDC: Hmm! \nbgoeden: Share. Button green down in the middle. \nJaime Lopez | BCDC: Yeah\, okay\, is that working hopefully. \nbgoeden: I give it a minute for the screen to load. There we are. \nJaime Lopez | BCDC: Okay\, so what are you guys seeing right now\, like the actual presentation\, or like the presenter view. \nbgoeden: The cut\, the actual presentation. \nJaime Lopez | BCDC: Okay\, so what if I do this is this\, is this still a presentation. \nbgoeden: Yes. \nJaime Lopez | BCDC: Okay\, great awesome. Okay\, yeah. Like. \nJaime Lopez | BCDC: like Commissioner showalter said\, I’m Jaime Lopez\, and I’m 1 of the environmental scientists here on the Bcdc team \nJaime Lopez | BCDC: working with Brenda. \nJaime Lopez | BCDC: And so since it’s been a while since we last met\, and there’s probably a couple of new people that have joined \nJaime Lopez | BCDC: like the group\, we thought it’d be a good idea to kind of do a brief recap on \nJaime Lopez | BCDC: on the sand mining activities that it has occurred\, not also basically on like so who’s involved? How’s it done and where it’s happening and and what the second half \nJaime Lopez | BCDC: basically introducing like San Francisco\, based Pic environment \nJaime Lopez | BCDC: just to set the stage for for their discussions that are gonna that day. \nJaime Lopez | BCDC: So okay\, so as we’re all familiar. \nJaime Lopez | BCDC: send money occurs in 3 locations across the bay\, and the 1st location is Central Bay\, which is \nJaime Lopez | BCDC: leads to modern lease\, to modern Marietta by the State Lands Commission. And typically\, this area is this mining area \nJaime Lopez | BCDC: which are seen here in blue \nJaime Lopez | BCDC: they are up to 90 feet deep. And it’s also important to note that. So Raccoon Strait. There’s no mining happening there which is kind of northwest of Angel Island\, and so much of the \nJaime Lopez | BCDC: went to the mining area \nJaime Lopez | BCDC: contains coarse green sand\, while finer sand are kind of located on the southern end. Here\, near residial shoal\, which is adjacent to crazy fields. \nJaime Lopez | BCDC: and are primarily used\, and like the sand\, is primarily used for concrete and and asphalt production \nJaime Lopez | BCDC: and moving up towards Sussoon. So Sussoon Bay has 2 lease areas. \nJaime Lopez | BCDC: and the 1st is some middle ground show\, which is a \nJaime Lopez | BCDC: which is near an island and has a private lease that is typically mined by Lynn moraine. \nJaime Lopez | BCDC: and with the second lease area being further east in the channel \nJaime Lopez | BCDC: that’s typically mined by Swiss and associates. \nJaime Lopez | BCDC: And this is a partnership between Lynn\, Marine\, and Martin Marietta\, and this is also leased by the State Lands Commission. So both these locations contain finer sands\, which are used for trench filling asphalt\, and like other purposes. \nJaime Lopez | BCDC: Now the whole purpose of sand mining is to be able to obtain so construction aggregates\, and it is not typically used for navigation. As such. The mine sand is a waste product\, and therefore mining is considered \nJaime Lopez | BCDC: beneficiary use. So the mining occurs \nJaime Lopez | BCDC: year round. As there are no established work windows. \nJaime Lopez | BCDC: But the equipment that’s used for these events are typically equipped with fish greens on the \nJaime Lopez | BCDC: on the water intake pumps\, and and this is to avoid entrainment of the fish. \nJaime Lopez | BCDC: Also. \nJaime Lopez | BCDC: It’s. It’s also important to note that these lease areas are typically mined \nJaime Lopez | BCDC: multiple times a year based on location\, the desired grain size\, and and the need of the industry. And here are some images of some of the equipment. That’s the hydraulic equipment that’s being used. \nJaime Lopez | BCDC: So you have a selection drag head\, which is here\, and I’m here in the center page where my cursor is pointing. \nJaime Lopez | BCDC: and on the right it’s more of like a suction pipe. \nJaime Lopez | BCDC: And here are 2 examples of mining event of mining that has occurred in Central Bay and and Middle ground shoal between 2\,007 and 2\,008. \nJaime Lopez | BCDC: So you would like to keep your eye on the colors\, because each color represents a mining event. \nJaime Lopez | BCDC: So many repeated is repeated in these areas. So within the leads that contain the desired grain size \nJaime Lopez | BCDC: of sand. And it’s also important to note that when mining this area\, when it’s constantly being repeated. \nJaime Lopez | BCDC: Mind the vendor communities in these locations are not allowed to \nJaime Lopez | BCDC: might recover\, and it’s also be removed constantly. \nJaime Lopez | BCDC: Now\, kind of shifting forward more towards the ecology piece \nJaime Lopez | BCDC: so now we’re looking at the subtitle sandy habitat \nJaime Lopez | BCDC: which are within these lease areas. \nJaime Lopez | BCDC: So we see that that location also influences the sand substrate and biodiversity. \nJaime Lopez | BCDC: as you can see in the image. Sand is mostly found in the deep water channels and central \nJaime Lopez | BCDC: and within the central bay \nJaime Lopez | BCDC: so deep water shoals that that are across across the estuary. \nJaime Lopez | BCDC: So if you were to focus just on Central Bay\, which is a stable marine system with strong currents and tidal exchange. \nJaime Lopez | BCDC: You’ll typically see a coarser sand on the northern side of the area and much finer sands \nJaime Lopez | BCDC: towards the southern end\, and as we move towards susume\, which is a more brackish system\, which experiences strong. \nJaime Lopez | BCDC: strong seasonal salinity changes. This is where we find medium to us\, we’ll find our sense here. \nJaime Lopez | BCDC: No\, it now muddy and sandy habitats also come to support Benthic or Bottom Bay\, also communities. \nJaime Lopez | BCDC: And these communities live on and within the settlement. \nJaime Lopez | BCDC: So here’s an example from Chesapeake Bay and her muddy bottom habitat\, which shows clams\, worms\, oysters. \nJaime Lopez | BCDC: and fish. So for San Francisco Bay. This could be a similar \nJaime Lopez | BCDC: configuration of organisms that that are found down there\, but they also have\, like other various fish species. \nJaime Lopez | BCDC: such as like never sharks\, halibut. \nJaime Lopez | BCDC: some bat rays\, some greased sturgeons\, some sand lances. \nJaime Lopez | BCDC: and other critters like that. But that’s also\, but it’s also important to know that specific species are also being dependent \nJaime Lopez | BCDC: on different environmental factors. And the location \nJaime Lopez | BCDC: also want to note that that many of these graphics throughout the presentation are going to be just illustration points. \nJaime Lopez | BCDC: and they are not journeys specific to the San Francisco Bay essentials\, because we’re looking through the literature. It’s pretty scarce. So there’s not that much information about our system specifically. And this habitat \nJaime Lopez | BCDC: now\, we’re gonna focus on why these communities are important. \nJaime Lopez | BCDC: So they do provide various environmental benefits \nJaime Lopez | BCDC: to the system as a whole. So this includes by having the so decomposers which are \nJaime Lopez | BCDC: typically breaking down organic material. There’s also the storing and release of carbon\, nitrogen\, and other nutrients within the system. \nJaime Lopez | BCDC: The water quality can also be enhanced\, as there’s sediment being removed from the water column. \nJaime Lopez | BCDC: So sediments are also stabilized and oxygenated by these critters \nJaime Lopez | BCDC: that are in the bottom bed. \nJaime Lopez | BCDC: And these communities are also important because they kind of link the food web and and pretty much that’s where it starts. \nJaime Lopez | BCDC: And lastly\, these communities can provide information about the health of a specific area as they are sensitive to environmental changes. \nJaime Lopez | BCDC: Here in the image is also another example of like the different types\, combination of critters that could be found but it. But again\, like this is not specific to our system. \nJaime Lopez | BCDC: Now\, these habitats can also be used by other species for foraging\, resting\, some migrating\, and spawning grounds. \nJaime Lopez | BCDC: but it’s also important to note that not all the ethic communities or habitats are the same. \nJaime Lopez | BCDC: For example\, like what habitats which have \nJaime Lopez | BCDC: which occur in quieter areas\, which which are less disturbed\, tend to have more species and diversity \nJaime Lopez | BCDC: in part due to the nature of that habitat specifically as well. There are higher levels of nutrients \nJaime Lopez | BCDC: up present. \nJaime Lopez | BCDC: You compare that to sandy\, deep water shoals. By their nature there are more disturbed by tides currents. \nJaime Lopez | BCDC: but they also have species that are located there that are specialized in that given area. \nJaime Lopez | BCDC: So we incorporate mining. That kind of increases the disturbance and creates an environment that’s kind of different from a naturally disturbed one. \nJaime Lopez | BCDC: And that causes the removal of these bending critters. \nJaime Lopez | BCDC: And also within these areas that are highly disturbed \nJaime Lopez | BCDC: there\, there’s typically to be like low species\, numbers in abundance\, and there are also at a \nJaime Lopez | BCDC: at like an early stage or moderate stages of of community so development. \nJaime Lopez | BCDC: And here’s like more examples here on the right hand side. That kind of show you what a perfect community \nJaime Lopez | BCDC: that’s mostly sandy \nJaime Lopez | BCDC: at Corpus Christi\, of what it might look. So you have some worms\, some clams that are buried within the sediment. \nJaime Lopez | BCDC: and then you have like crabs on top of that\, snails and some fish\, and then the bottom one. You kind of see another representation of what it might look like \nJaime Lopez | BCDC: at a soft bottom habitat that’s again at Chesapeake Bay. \nJaime Lopez | BCDC: No\, this is now looking at pre accessibility\, because there are critters that are there that are important. So within the food chain. \nJaime Lopez | BCDC: So there are different organisms and life stages of a species that can vary access\, varying specific depths so influencing like that food accessibility for predators. \nJaime Lopez | BCDC: so depending on the predator\, like the mouth\, size\, and shapes\, can vary also. \nJaime Lopez | BCDC: This makes this is kind of like making so different food sources important for different species. \nJaime Lopez | BCDC: And if you look at the age of the predator\, that kind of also influences what prey\, size. \nJaime Lopez | BCDC: and type they can access within \nJaime Lopez | BCDC: within the Beth floor. So\, for example\, if you focus on this picture specifically if we look at the leopard shark here \nJaime Lopez | BCDC: so we could see that the colors that those little colors around them that kind of influences like their food type. So we could see that for the leopard shark there’s higher densities within the upper layer of the sediment between\, like we \nJaime Lopez | BCDC: so between like 0 to 4 cm. \nJaime Lopez | BCDC: as opposed to the lower densities that are from 4 to 10 cm\, that that are much deeper in the sand. \nJaime Lopez | BCDC: So it’s also important to note that\, like an adult shark or like leopard shark\, would be able to access this whole depth \nJaime Lopez | BCDC: as compared to a juvenile. \nJaime Lopez | BCDC: But then\, if my need happens\, like you are removing this upper layer. \nJaime Lopez | BCDC: and that’s kind of removing a resource for juveniles. \nJaime Lopez | BCDC: and if that resource is removed\, then that means they would have to forage somewhere else. And this is kind of why it’s important to have like a diverse benefit community that that’s important to wildlife foraging. \nJaime Lopez | BCDC: Here’s a different perspective. But this is more looking at dredging on how it may be impacting \nJaime Lopez | BCDC: like the vendor community. But this is a more of like a sketch \nJaime Lopez | BCDC: of navigational dredging. But the overall message is the same. \nJaime Lopez | BCDC: So if you were to focus just on the left hand panel\, which says\, Undred area. \nJaime Lopez | BCDC: and you kind of notice that there’s like an abundance of critters. \nJaime Lopez | BCDC: And throughout the sediment depth. There’s different size. \nJaime Lopez | BCDC: invertebrates\, and that changes as you go deeper and deeper. \nJaime Lopez | BCDC: And then\, since that’s there\, like\, you also have\, like a diverse presence of foragers that are feeding at different levels as well. \nJaime Lopez | BCDC: And if you start shifting over to the dredged area\, you notice that that upper layer of sediment has been removed. \nJaime Lopez | BCDC: So with that that comes with a decrease in price\, size\, and abundance. And you can also see that there’s a potential to lose those prices of \nJaime Lopez | BCDC: of forgers that are there. \nJaime Lopez | BCDC: and if we and then on the last panel\, which is like between 2 to 4 \nJaime Lopez | BCDC: years of post dredge\, you kind of see how the banthic floor is recovering by the sediment that has accumulated\, and you’re starting to see a partial recovery of the community. But then again. \nJaime Lopez | BCDC: but then\, like\, you’ll also see the return of some forwarders coming back slowly. \nJaime Lopez | BCDC: and they’re feeding on different prey as well. But it’s also important here to know that like this takes a lot of time\, and it’s very dependent on how resilient the community is\, and like their ability to \nJaime Lopez | BCDC: kind of recolonize or reestablish that area after the disturbance has occurred. \nJaime Lopez | BCDC: Yeah. So that was pretty much a very brief introduction of the world of the communities. And so coming up next\, like\, right after this presentation\, this would be 2 studies that are \nJaime Lopez | BCDC: focus heavily on the impact of sand mining. \nJaime Lopez | BCDC: And that’s pretty much it. In the meantime\, if there’s any questions like\, feel free\, please feel free to ask them now. And yeah\, us. Thank you. \nPat Showalter: Okay\, well\, we have one question. This is time for questions. So if you have a question\, please \nPat Showalter: raise your hand. \nPat Showalter: And I will call on you. And there is one question in the chat. \nPat Showalter: Would you like to respond to that 1 first? st Jaime. \nJaime Lopez | BCDC: And jaime. \nbgoeden: If you want. If you want me to help you with that question\, I can. \nJaime Lopez | BCDC: Sure bro yes. \nbgoeden: So I’ll I’ll go ahead and answer it. So the question is whether or not why sand mining doesn’t have work windows. \nbgoeden: So\, and I think Rea is with the Army Corps of engineers\, and I think the comparison is probably to navigation dredging\, which is subject to work windows. So nav dredging has work\, windows of June one to November 30\, th and August 1st to November 30th east of the Carquinez Bridge. \nbgoeden: So the sand mining projects went through individual consultations. \nbgoeden: and they as part of that consultation. Early on with cowfish and wildlife\, they implemented fish screens on the intake pipe. So when Jaime was showing you the equipment aria with the dredging. You saw those silver cylindrical pieces put on the water intake pipe \nbgoeden: of the mining equipment. That was a primary area of entrainment for fish over 15 and so the miners were able to reduce that impact by implementing fish screens and the resource agencies determined that that was sufficient to address the main concern on entrainment from the water. Intake and mining also needs to occur occur year round to supply \nbgoeden: sand to the construction industry\, and they found that to be a compelling issue there is a reduction in the amount of mining that can take place in the Sassoon lease areas during the spawning season kind of the late winter to mid early spring period\, where there is mining restrictions to greater than 25 feet\, and \nbgoeden: a volume limitation of\, I believe\, 54\,000 cubic yards total for those 2 lease areas during that period. \nPat Showalter: Okay\, thank you. Are there any more questions for Jaime? \nPat Showalter: I don’t see any raised hands. But I’m not \nPat Showalter: okay. All right. Then I understand that Commissioner Gunther would like to make a comment before the next presentation. So Commissioner Gunther. \nAndrew Gunther: Thank you\, Pat. I just want to advise everybody that prior to Mister Johnson speaking\, I was one of the founding partners of applied marine sciences starting in 1991 \nAndrew Gunther: and I worked full time there until around the year 2\,000\, then part time for many years after that. So I was likely a I think I was a part time employee at applied marine sciences. By the time when this study was done\, however\, my partners knew better than to let me near any analysis \nAndrew Gunther: apology. So I didn’t actually participate at all in this project\, and I am now no longer associated in any way commercially with applied marine sciences. So I just thought that should be on the record. And if anyone has any questions\, please reach out to me\, or if for some reason\, someone thinks I need to contact the Council of Bcdc. And discuss this\, I will do that as well. Thanks. \nPat Showalter: Right. Are there any questions associated with this at the moment? \nPat Showalter: I see none. Okay. Well\, then\, we move on to the presentation. By Jay Johnson. He’s the applied marine sciences\, senior oceanographer\, and he’s going to present findings from the Benthic survey of commercial aggregate mining leases in Central San Francisco Bay and Western Delta. \nPat Showalter: And this was this study was conducted as part of the State Lands Commission\, Environmental Impact Report on mining in San Francisco Bay. \nPat Showalter: and the Commission Working Group and members of the public will have an opportunity to discuss the study and the findings. Afterwards we have put the find\, the study. Oh\, I just want to mention that \nPat Showalter: the all of these studies are listed in the additional material section on the calendaring item for this meeting. So they’re readily available. If you would like to read the whole study. Okay\, with that\, Jay\, are you ready? \nPat Showalter: Stay here. \nbgoeden: He is here. He’s on mute. \njayjohnson: I’m hilarious. \njayjohnson: I might have to exit and get back in. I haven’t shared before on on Zoom\, and it’s telling me when I go to share my screen\, I need to exit and re-log in. So if you’ll just give me 30 seconds\, I’ll do that all right. \nPat Showalter: Sure. \nbgoeden: Thanks\, Jay. And actually\, that will give me a brief moment to say to folks who have joined us today\, thank you for joining\, if you would please put your name and affiliation in the chat. So we can add you to our interested parties list. Because some folks we just have a phone number. And so if you’re new to the group\, we won’t \nbgoeden: know who you are to be able to add you to the Commissioner Working group interested parties list. If you would like to be so\, if you could do that\, that would be great if you don’t want to. That’s okay\, too. But that’s 1 way for us to stay connected to you all. \nPat Showalter: I would also like to take this opportunity to thank Stoll Reeves for sending us a letter yesterday. It’s signed by Christian Marsh\, and basically\, it sums up all of the scientific information. \nPat Showalter: It’s sort of a summary of the scientific information relative to sand mining and the benefit impact in San Francisco Bay\, and I see Christian is here. I’m sure he’ll talk about it a little later. But thank you for sharing that\, and it is listed in the additional materials section. So it’s available for everybody to read. It’s a it’s a 6 pager. So it takes us a little while\, but it’s still very clear and easy to read. So thank you for that. \nbgoeden: Alright. I’m ready to go if you’d like me to start. \nbgoeden: Yay. \nPat Showalter: Perfect\, go. \njayjohnson: Okay\, let’s try this. Okay\, share. All right. Allow. Oh\, why is it telling me? Zoom workplace? Never mind. Can you see my screen. \nPat Showalter: We can indeed. \nbgoeden: You are in you’re not in presenter mode yet\, though Jay. \njayjohnson: Let me do that. I can do that. There we come on. \njayjohnson: there you are! Here we go. \njayjohnson: all right. So in 2\,008 \njayjohnson: ams. Applied marine sciences conducted a Benthic infunnel assessment of the mining leases\, and the field work was done in the fall of 0 8\, and then the report was published in 0 9\, and became part of the initial Ceqa. Analysis for the 2\,012 Eir. \njayjohnson: My name again\, my name is Jay Johnson\, and I’m a senior oceanographer with applied marine sciences. And I’m also a \njayjohnson: marine ecologist. So this study\, as as Jaime mentioned earlier\, that when we looked at \njayjohnson: what was going on\, and wanted to evaluate what the potential effects of sand mining\, aggregate sand mining in the bay might be on Benthic communities in general\, and there isn’t a lot\, especially in Central Bay\, known about communities. We designed a study to look at the various mining leases and try to assess what kind of ecological conditions\, habitat functionality\, benthic community structure\, etc\, was going on in the \njayjohnson: mining leases. And so our study goals were. The primary goals were to characterize benthic communities inhabiting the mining leases. We wanted to characterize what we’re inhabiting\, what kind of benthic communities. And when I say\, Benthic\, we’re primarily talking about infauna\, the animals that live inside the surface layers of the sediment\, and in some cases the Epipuna\, or those larger organisms that may be on top or attached to the top \njayjohnson: of the the seafloor sediment. \njayjohnson: and we were going to look at both mining lease\, composition as well as control sites or comparison sites. And then we were going to try to identify or assess the difference between communities inhabiting mining leases and control comparison sites. \njayjohnson: Let’s go. Okay. But we also had a secondary thought of obtain a better understanding of the recovery rates and timing of benthe communities inhabiting sand mining leases\, following sand mining events. There has been a lot of work done in the Gulf of Mexico and along the eastern seaboard by what is now Boem used to be minerals management service\, looking at aggregate mining for beach \njayjohnson: restorations and the recovery of those communities in an open ocean environment. So the study was designed around 20 samples being collected within mined leases. \njayjohnson: and of those 8 of those samples were collected along mine tracks. That means someplace where miners had come through\, and Jaime showed that image of what we call worm tracks. The samples were collected or attempted to be collected within those worm tracks\, and then 5 samples were collected from control and comparison sites. The delta being a smaller lease area. \njayjohnson: We collected 10 samples within the mine leases\, 2 of which were in tracks and 5 were in control comparison sites. \njayjohnson: and we said the work was conducted in August of 2\,008. This is an old figure\, showing at that time the mining leases that were up for consideration\, and most of these are still there. Some of them have changed their boundaries a little bit\, but they show you how we randomly distributed\, so that there were samples collected in every lease area\, at least 2\, if not more\, in some cases 3\, \njayjohnson: and then the boxes marked in white were our control comparison sites\, because we knew that the sediment composition in the northern area of Central Bay was a little bit different than that along the southern \njayjohnson: portion of Central Bay\, and we want to make sure we captured those for those of you who are amateur historians like me. If you look at that blue triangle up by Angel Island in Raccoon Straits. That’s where all the sediment was mined for Treasure Island \njayjohnson: back in the twenties. So just Fyi\, I mean\, that was one of the cocktail tidbits we picked up as we were doing this study and then back in the Delta. We already talked about middle ground shoals\, which is the site in blue\, and then what is called Susan Bay or the Delta sites\, and going through. So \njayjohnson: what did we learn I’m going to start going\, and there’s going to be a lot of slides here. I’m just going to skip over\, because this was a presentation we gave some years ago. And and the data is there. So what we discovered was that Benthic community composition is highly variable. \njayjohnson: It’s very responsive to microhabitat conditions\, and that physical factors\, water\, depth\, salinity\, temperature\, sediment\, composition and stability\, organic enrichment. And Jaime mentioned that about decomposers\, so in order for decomposers to be in the makeup of the Benthic community \njayjohnson: there has to be organic compounds. There’s got to be something for them to consume. And I think that’s a very important consideration. \njayjohnson: And so it’s really critical to controlling variation in the community. Composition data is understanding and controlling the ecological parameters. Sediment\, composition and water depth are the 2 major physical factors that we know affect Benthic community structure. And one of my earlier slides. We talked about Microhabitat \njayjohnson: and one of the things that we’ve learned both Ams and other researchers who’ve looked at mining aggregate mining of any kind is that you have very close microhabitat composition\, so you could literally move \njayjohnson: a foot away if you will\, from one sample to another \njayjohnson: and pick up a dem different benthic community. Excuse my phone. I can’t. \njayjohnson: 8. \njayjohnson: Sorry about that bent. The composition \njayjohnson: can change because the sediment composition may change\, or the amount of organic carbon may change. The classic example we see in the open ocean is when you get near shore\, where you have sand ripples\, and and in the ocean \njayjohnson: you have one benthic community on the leading edge of the sand dune if you will underwater one along the top and one on the backside\, and the reason being is that on the top of this sand ripple are being predominantly affected by ocean currents. More energy\, higher energy. The organisms living on the leading edge of the sand dune are being constantly moved by high energy. \njayjohnson: But then\, on the backside the shadow side of the sand dune\, if you will\, is where all the carbon is depositing. And so we’ll have actually different communities living there. \njayjohnson: So that’s 1 of the reasons why in our study we always take our samples and we split them so that we do our chemistry on one half of the sample and the biology on the other half\, so that we always know that the Benthic community that we’re describing is from the composition\, the sediment\, composition\, and the physical factors present. \njayjohnson: And this is just a real quick slide. But we tried. This is a central bay. All of the water depths were very similar within the same water zones. You can also see that in the central bay most of the sand is coarse to medium with a little bit of fine. \njayjohnson: and then in the more in Central Bay\, much the same\, and then in the Delta we’re seeing\, as Jaime said\, much finer sand\, mainly fine and medium sand\, and the water depths in meters is much\, much lower. \njayjohnson: I’m not going to try to make you understand this\, because there won’t be a quiz. \njayjohnson: But this just shows all the animals that were collected analyzed. One of the things that we did in our study is when you do Benthic\, in funnel analysis you get the mud\, and then you got to separate all the animals out of the seafloor mud. \njayjohnson: and you what’s called screening\, and you run them through micrometer millimeters. Yeah\, millimeter screens. And the typical standard is either 1 or half millimeter. We did the split in half millimeter. And we actually analyzed the 1 separate from the half millimeter samples because the smaller animals get caught on the half millimeter screen\, whereas the larger animals get caught on the 1 screen. \njayjohnson: and a lot of the species composition that we were able to use in our statistics actually came from the half millimeter smaller animals. So I think that’s important to note \njayjohnson: Central Bay. There is the presence of an epibentic community of barnacles\, briozones\, and hydroids that were attached to large shells in cobble \njayjohnson: covering surface sediments. In some of the locations there was a Megabentos epibentic community present in the case of sea anemone sea stars and various crustaceans. So once we got all our data\, what we quickly do is some kind of statistical analysis\, and this is multivariate clustering analysis. And what this told us is that when it looked at the differences in variation\, what made one \njayjohnson: site different than the sample from one location different from the sample from a separate location in the species. Composition\, abundances\, sediment\, composition of concentration of organics \njayjohnson: and central bay basically clustered into full 5 basic groups. The red\, orange\, green design\, you know\, there’s a blue one here\, but it wasn’t too important\, and then a navy blue\, but then at each level we can then re-look to where we can describe one master community. \njayjohnson: another slide. I really don’t want to worry about too much\, but what we see here\, which is\, I want to point out is that from 3 of our for 2 of those sets of samples little nematodes\, little round\, red\, round worms were predominant. I mean they dominated the community. \njayjohnson: In another one you had a little more cluster\, 3 evenly distributed over multiple species in Cluster 4. It was a series of sites\, that neutrocola\, which again is one species. And then we had another site\, another set of samples that had much higher abundances\, much higher species\, diversity. And that’s all I want to say there\, and this is why these species groups broke out \njayjohnson: cluster one was the nematodes cluster\, 2 was predominantly nematodes and cluster 3 was somewhat split between polychaetes and amphipods. \njayjohnson: And what I want to point out is that most of these polychape species were not detrital feeders\, but carnivores okay\, worms that actively look for other animals to eat\, and then in cluster 4\, we had predominantly bivalves small\, you know\, clams\, and then in cluster 5 again. Bivalves\, polychaetes\, and amphipods dominated the community structure. \njayjohnson: This figure quickly shows you those 5 colors and how they’re kind of distributed all over the place. \njayjohnson: We didn’t see any one set of dominant species. \njayjohnson: I want to go back to Green. So you see\, Green is the one that’s a little more evenly distributed. \njayjohnson: We’ve got a little bit of everything everywhere\, and that shows us that we have \njayjohnson: high high. What we suspected was a high level of microdiversity microhabitats throughout the area that are all somewhat similar in composition. \njayjohnson: What did our statistics ultimately tell us? There were no detectable differences in either. The taxa abundances\, the number of organisms\, the number of taxa between mining leases and the control sites. Now our control comparison. Sites are sites that have no mining activity at all\, but have similar physical conditions\, similar \njayjohnson: sediment\, composition\, because we spent a lot of time finding these sites that they were true comparison sites\, and we saw no difference in tack abundances\, organisms\, taxa dredged and undredged sites. So when we looked at those sites\, the samples that we had collected within tracks\, mining tracks that had occurred within a couple years\, we couldn’t see any difference. What detectable differences we did detect is that there was more medium and fine sand at the control sites than the mining leases. \njayjohnson: No\, duh\, because what are the miners looking for? Medium and fine sands? \njayjohnson: And cluster? 5. That last one that was\, you know\, very diverse multiple multiple species had higher abundances\, were water\, depth and medium gravel. So they were slightly deeper and they were \njayjohnson: gravel. You’ve got to be careful in geologic terms. Gravel isn’t what we think of gravel when you go to the store and buy a bag of gravel. Gravel is anything larger than \njayjohnson: large sand. Okay\, when we ran the stepwise regression\, which is a statistical technique that looks at. \njayjohnson: how do you continually account for increased variation until you account for all of the variation between all your samples. What we learned was that Ampelisca\, which is an Arthropod Megamora\, which is also an Arthropod Nemurdia\, which is a roundworm nephtease\, which is a polychaeaten triatella\, which is again an arthropod\, are positively associated with time\, since dredging \njayjohnson: basically it says that we get more individuals with increasing time since dredging\, whereas Armandia \njayjohnson: and that’s what’s called a pea colonizer. Armandia is \njayjohnson: in ecological terms. Those species that tend to show up the 1st time after a disturbance or some effect that is keeping other species out. They were negatively associated with times in stretching\, which means you have fewer individuals with increasing times in stretching. And that’s exactly what you would expect to find in a disturbed area \njayjohnson: delta cedations. The 1st thing that you should look when you look at this table and I apologize. It’s a lot of data is\, the numbers are extremely low. Abundances are very small in the Delta. When we did our clustering analysis. We basically saw 3\, but essentially only 2 different community structures \njayjohnson: cluster. One is dominated by bivalves\, which is the invasive Asian clam\, core\, corbula cluster. 2. \njayjohnson: The Polykeet was the dominant\, and this is a invasive\, not an invasive\, but but a \njayjohnson: polykea. And then the bivalve corbicula\, which is also an invasion. Asian clam. The difference between corbicula and corbula has to do with salinity and what the water salinity is\, and then cluster. 3\, the bivalve corbula. \njayjohnson: So this is important\, because these were the 2 dominant one and 3 were the 2 dominant community structures in the Delta cluster\, one cluster\, 2\, \njayjohnson: all right? So Corbela cluster. Yeah. Corbula is here\, and corbicula is over here. So here cluster 2. \njayjohnson: And again\, like we did with central Bay. These are\, how they kind of spread out\, and they are somewhat randomly spread out. \njayjohnson: What did we see in the Delta? We could not detect any differences in tax abundance between mining leases in the comparison sites. And once again\, what we did see was that higher amounts of medium and fine sand in clusters one and 3\, whereas cluster differ in number of organisms per taxa. \njayjohnson: The stepwise regression showed that media mass\, just the poly key and number of taxa negatively associated with the time zone stretching. So what this is telling us is that fewer taxa \njayjohnson: and media mastis becomes more dominant with increasing time since dredging. \njayjohnson: So what does it all mean central Bay Benthic community? It’s characterized by marine species. \njayjohnson: not brackish water or estuary species. We have low species\, diversity\, and abundances\, which is typical for sandy sediments\, because there’s no organic carbon. You don’t have any of those detrital feeders. They just don’t exist. There’s nothing for them to eat. Small scale. Microhabitats do exist\, and they are supporting shift in the species\, dominance and community. \njayjohnson: The central Bay region\, mining sites and comparison sites are subject to very high currents and unstable sediments which is reflected in the in funnel\, community and composition and structure. It’s the physical conditions in Central Bay that are predominantly affecting what you’re finding \njayjohnson: there. And that was because we didn’t see any difference between the comparison sites and the mining sites. Central Bay Benthe community natural disturbance and mining disturbance act in similar ways in controlling the Bentha community development and its recovery. Unstable sediments keep communities closer to what we call an R\, \njayjohnson: which is an opportunistic or invasive\, a recovery type site than a K community which is equilibrium. Many of the slides that Jaime was showing are what would be considered equilibrium communities\, communities that have peaked out that have developed to their maximum productivity and species diversity. \njayjohnson: our communities aren’t that way. Our communities\, if any of you ever took an ecology class in high school. The classic discussion is. \njayjohnson: the farmer comes in and cuts down all the trees and creates a field\, and he farms\, and then he lets the field go. What happens? Well\, the 1st thing that happens is the field starts to recover to pre disturbance conditions. So we see grasses. Then we see some bushes and some shrubs. We see pine trees and early invading type trees coming in\, and ultimately over. Some time it’ll return to its maple oak or birch forest. \njayjohnson: The other thing that was interesting is that those sites that we saw a higher gravel\, so coarser\, really coarse material contents in the sediments\, that it appears that the gravel itself is acting as a stabilizer\, which is enabling the community development to move towards a more K equilibrium community. And if you remember that 1 5\, th that 5th \njayjohnson: set of community structures and the figures we showed where you had a lot more diversity\, a lot more species abundance across the taxa. That’s what we were seeing in those sites \njayjohnson: done yet. So that was this cluster 5 \njayjohnson: and the same thing in the Delta \njayjohnson: changes over time. What were our Central Bay conclusions? The community appears consistent with past studies. There was a study done in 1990 by marine ecological consultants\, and they reported low diversity\, low abundance\, nematode and polychae dominated communities and a thriving epibentic community. This is in Central Bay. The regional monitoring program\, however\, has done a more\, as you’re all familiar with San Francisco Estuary Institute\, did a huge spendthic study over multiple years looking at \njayjohnson: benta communities throughout the Bay\, and this was published in 2\,000\, \njayjohnson: and so for San Francisco Bay. We probably have a much better idea of how diverse our Benthic communities are. And what are the physical and sediment\, composition factors that control those and the sandy marine habitat community that they talk about is one of low diversity\, low abundance as they’ve seen throughout the bay. \njayjohnson: and then\, finally\, that polychats and nematodes dominated the community in the Rmp. And red rock\, and we saw that with the nematodes in Central Bay \njayjohnson: conclusions\, sand mining effect on Benthic. In funnel communities it does not appear to be any different than natural conditions and affecting community composition. Recovery to Pre. Mining conditions should be quick less than one to one year\, because it’s not trying to recover back to a cake type community. It’ll never get there. The physical conditions are affecting it and preventing it from reaching that \njayjohnson: that state\, and then the constant release of coarse gravel and cobble from depth to surface should be beneficial to in funnel community development\, and that the effect on Megabentos megabentos are those large animals like crabs. \njayjohnson: large snails is unknown because they are not typically caught in grabs. \njayjohnson: Delta Benthic communities is characterized by an estuarine species dominated by the invasive mollusks\, corbicula\, and corbula. What those studies with what we believe\, and we would need to gather more data to confirm. But it looks like that when mining comes in it removes enough of the corbicula and corbula \njayjohnson: clams which are very effective competitors\, and allowing natural recovery to native type species. And then over time\, corbicula and corbula out\, dominate the existing native community. Mining appears to occur in depositional areas along navigation channels that are subject to natural disturbance and movement \njayjohnson: and small-scale microhabitats exist which support different species\, dominance. \njayjohnson: natural disturbance and mining act in similar ways in controlling the Benthic community development. The unstable sediments keep community closer to an r versus A. K community and the effects of the invasive clam species on benthic community composition is truly unknown\, but appears to be very significant. \njayjohnson: All right\, I think we’re going backwards. \njayjohnson: Yeah. Sand mining acts similar to natural disturbance and recovery should happen one to one year. \njayjohnson: All right\, let me stop share all right. Any questions. I guess \njayjohnson: it’s a lot of information. \nbgoeden: So the one question I have Jason’s nobody asked. Nobody else is asking a question. It’s 1 where we’re still feeling\, where there’s not a lot of information\, so I’d love your perspective on it. So your study looks at one year greater recovery. But when we have \nbgoeden: mining that’s taking place regularly do we have any idea of like \nbgoeden: whether or not the mined areas that Jaime showed\, for example\, would have some recovery within\, you know\, a month or so of a mining event. If the mining is taking place relatively steadily throughout the year. \njayjohnson: I mentioned earlier \njayjohnson: that there have been a bunch of studies that have been done on the east coast in the Gulf of Mexico\, and there was even a study that we participated as the marine \njayjohnson: biologists for what was minerals management service. Now Bohm and Bessie\, that looked at recovery rates and recovery and ecological destruction of benthic habitats where the States are mining sand for beach replenishment. So we’re talking\, you know\, huge huge volumes. \njayjohnson: and what they were what those studies have basically concluded\, and some have been done in Alaska where there’s mining for gold and other minerals. Is that how the mining occurs. \njayjohnson: and when the mining occurs has the biggest effect on recovery rates. \njayjohnson: When you go in and mine a huge\, you know\, 4 acre area or 10 acre area. Recovery takes longer because recovery is predominantly from \njayjohnson: recolonization. We talk about these animals spawn and they get into the marine soup\, and then they settle out and start to recolonize. \njayjohnson: That just takes a little bit longer. And also in that kind of mining\, the way they do it. And again\, the physical environment\, the open ocean. The sediment composition tends to change \njayjohnson: so that you end up going from a sandy\, coarser area to a depositional area which then collects more carbon\, and we talked about the same\, you know. If you think of a sand dune\, you know that’s my classic example. You know\, you’ve all been to the beach\, where you have sand dunes and they move. You know you have the leading edge. You have the top and you have the backside. The backside has the carbon\, the front side doesn’t\, and the top is more physically disturbed \njayjohnson: because we change the carbon composition. The total organic carbon in the sediments. Then the species that are going to reinhabit that area are going to be different. \njayjohnson: Just like here\, we’re seeing mainly very few detrital feeders. And we see a lot of carnivores. We see a lot of filter feeders\, worms\, and stuff that stick their head up in the water column and try to filter out the plankton and other stuff in the water column. \njayjohnson: The mining studies also then showed that if you do what I like to call strip mining\, if you\, instead of running mining all the sand out of a 4 acre area\, you did strips in which you left areas undisturbed between the strips. \njayjohnson: Okay\, colonization happens much quicker\, because the primary means of recolonization in those events is from immigration and emigration\, not \njayjohnson: colonization from the soup\, if you will. Does that make sense? \njayjohnson: Because we have areas that are undisturbed. Animals grow\, expand and move\, they immigrate into the disturbed areas. And so recovery is much faster. And that’s why we tend to say that recovery in most communities will reach pre-disturbance abundance within a year to 2 years\, depending upon the physical conditions. \njayjohnson: Now\, how does that apply to what we see in Central Bay and the Delta totally different circumstances. \njayjohnson: because any carbon that’s in the water column isn’t settling out. \njayjohnson: That’s exactly what the sediment transport studies are showing and what we showed even in the areas where mining had occurred. The sediment composition isn’t much different than the sediment composition in areas that have never been mined \njayjohnson: or that have been mined many years ago. Because the recolonization isn’t. \njayjohnson: You can’t recolonize to something different. \njayjohnson: because the physical factors that are affecting those sites are so great or appear to be so great. That’s the controlling factor. It’s not the mining. It’s the 2 and 3 not currents that we see in Central Bay. It’s the 2 not currents we see in the along the channels\, the main dredge channels where the ships are going in the Delta. \njayjohnson: That’s where the mining is occurring\, and as far as recolonization\, these worm tracks are more akin to strip mining my term strip mining where you do. Mining with strips and areas aren’t being disturbed over and over again \njayjohnson: that there’s a chance for some recovery. You could argue\, and this is just my personal opinion\, but I\, you know\, can’t prove it at this point is that probably mining in the Delta is probably a good thing\, because it’s greatly disturbing the potamo corbula and corbicula composition\, and at least\, you know\, allowing some of our native species to take hold and and stay there because you need some physical disturbance to get them out of there. But that’s not going to happen. Did that answer your question\, Brenda? \nbgoeden: Yeah\, no\, that did. Thank you\, Jay. I appreciate the expanding on that. And I also I guess that just one other question. I’m not sure I can articulate it correctly\, but I’m going to try. So when you say the physical factors are the determinant. \nbgoeden: you’re talking about the same species coming in\, instead of a different species coming in. \njayjohnson: Exactly. Well\, no\, it’s 2 things the same species will recover will come in because the habitat hasn’t changed. \nbgoeden: Right. \njayjohnson: So you’re not going to suddenly change to a lot of detrital feeders if there’s no organic carbon\, and we’re seeing no evidence of anything in the central bay being depositional at all. \njayjohnson: It’s all erosional. It’s all all heavily disturbed. The currents are moving any carbon that’s coming in any carbon that’s in the bay\, working through the various basins\, is staying in the water column because of the high energy. \njayjohnson: so you can. Only your species can only recolonize\, based on the habitat that that they like. \njayjohnson: And if you’re not changing the habitat\, if the habitat isn’t really changing. That was that statement about mining is behaving much like the currents and the physical conditions. It’s just that’s just it. And so and what we’re seeing is\, it is recolonizing. And in fact\, in some cases\, and this was\, I wish we were able to get more data. \njayjohnson: those sites that appear to have been \njayjohnson: mine that had coarse\, really coarse material. \njayjohnson: We’re the most abundant and diverse \njayjohnson: communities\, because they had the the gravel. Well\, that’s being excluded by the miners. They don’t want it. \njayjohnson: So yeah. \nPat Showalter: You know\, they’re avoiding those areas. \njayjohnson: What’s that? \nPat Showalter: They’re avoiding those areas. \njayjohnson: Well to a certain degree\, but it’s also because of the way. And then one of the mine. There’s several\, you know\, bills here. They have screens when the sand comes up that keeps anything larger than a certain size from being collected\, and it gets discharged off\, and it gets returned to the seafloor. \nPat Showalter: Interesting well\, as a hydrologist. I always want to know what was the water year 2\,008 like I don’t remember. Was it. \njayjohnson: Was it a wet year? Was it an El Nino or an a la Nina? Is that what you’re asking. \nPat Showalter: Yeah. Was it a wet year\, or was it unusual at all? Do you remember. \njayjohnson: No\, not particularly I’m trying to think. The last prior to that 97\, 98 winter was the was a really bad El Nino year. So we were probably 2\,008\, probably a\, you know\, mixed of\, you know\, not really an El Nino\, but really not a la Nina\, you know one of our intermediate. \nPat Showalter: Period was in. It was a long term drought\, but \nPat Showalter: period. But but there were some. You know\, years where things were better than others. Okay. \njayjohnson: Yeah\, I can’t. I can’t speak to that because I did. We didn’t look at that. I mean\, you know\, it was a good fall. We had wonderful weather when we sampled so. \nPat Showalter: So that usually means it’s a dry year. Yeah. \njayjohnson: Yeah\, a little bit drier. Yeah\, well\, we don’t. We don’t typically start seeing. Then that’s why we did this in August is we don’t typically\, historically\, in the Bay Area or the Central coast. See our 1st rainstorms until late October\, beginning November. And and you know we have been involved with the regional monitoring program since its inception \njayjohnson: and handle all of the field collections for the regional monitoring program\, and those are always always scheduled for August\, September\, and at the very latest early October. So you avoid rains. \njayjohnson: you know. \nPat Showalter: Yeah\, okay\, all right. Well\, I’m not seeing. Thank you. That was a very that was an excellent presentation. I’m I’m not seeing any more hands raised for questions. But I’d like to give an opportunity for the minors to make a comment\, and or anyone else who wants to make a public comment\, and I’m assuming that’s going to be Christian. But whoever \nPat Showalter: is the miners would like to \nPat Showalter: represent them. I we’d be glad to hear from. \nChristian Marsh: Thank you\, Commissioner Showalter. I really appreciate that. I think we’ll we’ll hold off. We’d rather really focus on the presentations and make sure you can get through those first.st \nPat Showalter: Okay. Alright\, that’s that’s fine. Are there any more public comments associated with this other than questions? \nPat Showalter: Again\, I’m not seeing any raised hands. Does anybody else see any raised hands? \nPat Showalter: Okay. \nbgoeden: I don’t either\, Pat. I just dropped in the chat that\, according to the water group\, california was in an extreme drought in 2\,007\, through 2\,009\, according to the Natural Resources Agency and the California Department of Water. \nPat Showalter: Thank you. \nbgoeden: Love\, Google. \nPat Showalter: It’s wonderful\, isn’t it? All right? Well\, let’s move on to our next presentation. \nPat Showalter: I think that’s Tim. Hammermeister. \nTim Hammermeister: Yes\, that’s correct\, and thank you so much for being here and \nPat Showalter: Do you? Are you ready to. \nTim Hammermeister: Sure. Let me go to share screen. \nTim Hammermeister: and let me know if you’re seeing my presentation. \nPat Showalter: Are okay. And it’s full screen. \nTim Hammermeister: Excellent. \nTim Hammermeister: Yes\, I am Tim Hammermeister. I’m with Erm Newfields. We were just recently acquired by Erm. \nTim Hammermeister: New. We did this study under new fields. \nTim Hammermeister: And this is the Benthic assessment of sand mining in Central and Sassoon bays that we conducted \nTim Hammermeister: the data collection was 2016\, 2017\, \nTim Hammermeister: and then follow up reporting 2018 and 2020. \nTim Hammermeister: I’m like cover screen. Here. I’ve included a picture of a \nTim Hammermeister: a tool that we used in our study\, a sentiment profile imaging camera \nTim Hammermeister: that Jay actually provided an excellent segue. We were looking at the habitat types as a big part of our study. And with this camera\, you’re able to get a \nTim Hammermeister: picture of the sediment water interface to evaluate the type of habitat you’re looking at\, both in \nTim Hammermeister: the various features of the grain\, size and \nTim Hammermeister: presence\, absence of organisms and other visual indications. \nTim Hammermeister: And as I just wanted to present the picture because it’ll be part of the study that we came up. \nTim Hammermeister: So let’s move on here. \nTim Hammermeister: So the history of our study was. \nTim Hammermeister: we had an approved sampling analysis plan back in 2016 \nTim Hammermeister: that was developed through the Btac. \nTim Hammermeister: We we did our initial sampling in 2016 and follow up sampling in 2017\, both in October. \nTim Hammermeister: as I said\, we initial reported our results in 2018 \nTim Hammermeister: apparently. It satisfied the permit conditions. But then there was a request for some supplemental work that we did in 2020\, \nTim Hammermeister: and just to get start with the original study design. \nTim Hammermeister: Our objectives were to characterize the benthic habitat conditions. \nTim Hammermeister: compare the characteristics of the benta habitat before and after sand mining occurred. \nTim Hammermeister: and assess the potential impacts from the sand mining \nTim Hammermeister: and how the habitat would function 12 months following the sand mining. So we were looking at. \nTim Hammermeister: Is a year an adequate recovery period\, and \nTim Hammermeister: you know initially\, the idea was seasonally assessing the habitat conditions. But \nTim Hammermeister: it’s quite cost prohibitive. These studies are quite expensive\, especially bent to community analysis. \nTim Hammermeister: So we did one year to cover a full set of seasons and \nTim Hammermeister: see what the how the recovery rate was at that point. \nTim Hammermeister: Oh\, so our study design included \nTim Hammermeister: study sites in 2 different lease areas\, the treatment areas \nTim Hammermeister: and immediately adjacent to those lease areas were our reference areas and were controlled. \nTim Hammermeister: And we we picked reference areas that were right next to the lease areas to \nTim Hammermeister: that. But there had never been \nTim Hammermeister: sand line before\, nor were they \nTim Hammermeister: in one of the lease areas. But just to get the similar of habitat types as possible\, and hopefully. \nTim Hammermeister: guild. \nTim Hammermeister: Basically the same macro conditions over the year would affect both the \nTim Hammermeister: treatment and reference areas. So the data types we collected were the setup profile images from the camera. I showed on the 1st slide \nTim Hammermeister: our sediment\, conventional parameters\, Toc grain size. \nTim Hammermeister: And we did Bentha community analysis. We had Mts marine taxonomic services did the Bentha community analysis for us? \nTim Hammermeister: As I said earlier today\, we had 2 sampling events. Our T. 0 was \nTim Hammermeister: immediately prior to sand mining\, and then A. T. 1212 months after the sand mining was completed. \nTim Hammermeister: our study design\, known as A before after control impact. \nTim Hammermeister: This graphic presents kind of a \nTim Hammermeister: well. It’s a graphic of how the study design. It says we have a treatment reference area so that we’re looking at \nTim Hammermeister: what the conditions are in both mining and non-mined area arm. \nTim Hammermeister: The B parameter is\, do we see changes in the treatment area 12 months. \nTim Hammermeister: Post mining the C parameter there between reference areas is\, what are the natural changes over 12 months? \nTim Hammermeister: That would have occurred in these areas. So that’s that’s the real control factor. \nTim Hammermeister: And then the the D parameter is \nTim Hammermeister: okay. Were the changes different in the treatment area than the changes we saw in the reference area that were natural changes. \nTim Hammermeister: So it’s trying to tease out. \nTim Hammermeister: Are any changes seen at 12 months due to mining? Or are they just due to the natural changes that would occur over time. \nTim Hammermeister: because\, as Jay discussed in his\, these are very high energy areas\, relatively speaking\, in the bay. So \nTim Hammermeister: they’re always they’re basically in a state of constant change relative to an acquiescent bay. \nTim Hammermeister: whether it’s a physical\, man-made physical disturbance or just natural disturbance. \nTim Hammermeister: So let me see. Okay\, so here’s a map of our study area in Sassoon Bay \nTim Hammermeister: we basically collected 60 images using the sediment profile at 60 locations. \nTim Hammermeister: 90 images\, or 3 images per location. So 120 images across the reference and treatment areas. \nTim Hammermeister: Then we did a subset of. \nTim Hammermeister: I want to say\, I think it was 20 locations for Benthack community analysis. \nTim Hammermeister: Just we use the camera to get greater coverage \nTim Hammermeister: and the obviously the community to get the specific data. \nTim Hammermeister: Now in this map\, you can see these \nTim Hammermeister: little squiggly lines are where the sand mining occurred \nTim Hammermeister: in the treatment area. Now\, our design was to have a grid of samples just for spatial coverage and to be non-biased on where sampling we really wanted to just characterize the whole area \nTim Hammermeister: and the habitat type. But it’s key. It is key to note that in Sassoon Bay \nTim Hammermeister: the dredgers tend to anchor and \nTim Hammermeister: dredge in one spot. So the dredge trails here \nTim Hammermeister: are much smaller portion of the lease area \nTim Hammermeister: than what we’ll see in Central Base\, and unfortunately\, during this study \nTim Hammermeister: there was some more dredging completed\, but the GPS system on the \nTim Hammermeister: mining vessel was out\, so we did not get data for the other tracks\, but I was assured there would be similar to the ones you’re seeing here. \nTim Hammermeister: Same study design in Central Bay reference area \nTim Hammermeister: adjacent to the treatment area that wasn’t dredged \nTim Hammermeister: and a treatment area that was dredged. And you can see this is what I was talking about\, and the difference of how they mine. Here they tended to drift with the current. \nTim Hammermeister: and therefore creating much longer tracks\, dredging tracks through the lease area. \nTim Hammermeister: So the result results of our Bentha community analysis was in Port Knox Shoal Central Basin. \nTim Hammermeister: There was a loss of complexity. \nTim Hammermeister: but that loss of complexity was observed in both the treatment and reference areas. \nTim Hammermeister: So \nTim Hammermeister: it’s in that case it’s not clear whether any observed changings are from change are from the mining or just natural changes from year to year \nTim Hammermeister: into 2 May. \nTim Hammermeister: There’s a change in the overall community \nTim Hammermeister: with both the quantity and representation of the beta community. \nTim Hammermeister: The general metrics that you look at didn’t really weren’t really changed. \nTim Hammermeister: And the changes in the tax distribution again\, we’re \nTim Hammermeister: were not significant enough in one area versus the other to attributed specifically to sand mining. \nTim Hammermeister: The results actually showed up in the \nTim Hammermeister: in the soon area that the \nTim Hammermeister: community is slightly more complex at T. 12. \nTim Hammermeister: That very well could I to dig deep enough in the data to to to her \nTim Hammermeister: trigger my memory. But I have the I seem to recall. It’s because we got rid of a lot of these clams \nTim Hammermeister: in the trudge area\, and therefore the complexity because it was not dominated by a single species. The complexity\, therefore increased because\, one species was \nTim Hammermeister: less abundant. \nTim Hammermeister: Now\, the habitat conditions this is more from the camera results very similar because \nTim Hammermeister: you have the same high energy areas. What we find with the camera imaging and the data in the reports \nTim Hammermeister: is that the vast majority of both these treatment and \nTim Hammermeister: study areas as due to the high Rga\, we can \nTim Hammermeister: in the image analysis\, we consider it a stage one community. That means it’s a colonizing community. \nTim Hammermeister: I mean\, I could repeat a lot of stuff that Jay said. It’s high energy. It’s the type of community that exists in this type of substrate\, and it’s in a it’s used to constant physical change\, whether natural \nTim Hammermeister: or man-made. The physical change is not. \nTim Hammermeister: It’s kind of a it’s. It’s used the colony. That habitats there is used to that because of the higher energy in the system. \nTim Hammermeister: Are are from the camera. There didn’t seem to be any major changes in the habitat \nTim Hammermeister: after 12 months\, because it was the stage one at time 0. It was stage one at T. 12. \nTim Hammermeister: High energy\, sandy\, substrate. \nTim Hammermeister: Based on kind of backtrack\, a little bit \nTim Hammermeister: based on our study design since we did do a grid. And this is these are sizable areas and the sand mining was done over. I think a 1 or 2 week period. \nTim Hammermeister: and in Sassoon it looks like\, you know\, our stations. \nTim Hammermeister: Sand mining was such a small portion of the area. Our stations were somewhere further afield from the obvious sand mining. \nTim Hammermeister: Little little more crossover in Central basin. \nTim Hammermeister: So the question was raised. Well\, maybe we should evaluate a subset of these stations to see if if you really looked at these stations that were much closer to where the sand mining occurred \nTim Hammermeister: in this area and through the central part of the test area of the treatment area. \nTim Hammermeister: would there be any impacts? And our supplemental study \nTim Hammermeister: with the reduced data points\, even though the statistical power is lower. We really got the same results as we did when we looked at the same \nTim Hammermeister: as full data set some slight changes\, but the changes occurred in both the reference and treatment area. \nTim Hammermeister: You couldn’t discern whether the presumably that means the changes are natural. So therefore\, we could not \nTim Hammermeister: assign any observed changes to the effects of sand mining. Basically\, we found the same habitat \nTim Hammermeister: one year later that we found when we did the baseline studies. \nTim Hammermeister: And my understanding is this\, supplemental study was \nTim Hammermeister: also accepted under the permit conditions for the mining companies\, and \nTim Hammermeister: we haven’t done any subsequent data analysis or data collection. So this is where our findings were \nTim Hammermeister: from 2020. \nTim Hammermeister: That’s all I have for you today. \nTim Hammermeister: I don’t know if I’m still sharing or. \nPat Showalter: Thank you. I have a question\, and and I thought I was listening. You might have gone over this. But can you talk a little bit more about \nPat Showalter: how the image you know. What exactly are you taking a picture of when you put that camera down there. \nTim Hammermeister: It basically takes a 20 cm profile picture of the sediment water interface. It’s used depending on the depth of penetration and in sand. You don’t penetrate as far because the density of the substrate. \nTim Hammermeister: But you basically see the upper portion of the sediment \nTim Hammermeister: where the Benthic organisms live. You know\, typically the biological\, active zone is about 10 cm in a \nTim Hammermeister: inland bay. \nTim Hammermeister: And then you see the overlying water. So you can basically see grain size. \nTim Hammermeister: There’s any type of material on the surface\, whether it’s natural or any type of detritus. \nTim Hammermeister: We use this tool a lot for wood\, waste and stuff\, so you can delineate things that exist on the surface\, it’ll show you the oxygenated layer and the redox zone. \nTim Hammermeister: So typically in sandy environments\, it’s much more oxidized because the porosity of the sand and the water allows it to \nTim Hammermeister: it doesn’t go anoxic\, whereas in a on it \nTim Hammermeister: a shallow embayment with a lot of silk\, clay and organic material. \nPat Showalter: Oh! \nTim Hammermeister: Oh\, thank you very much. Yeah. \nbgoeden: I just popped open the study into the appendices that show the the spy camera. I thought it would be very illustrative\, as you try to explain it to us verbally. \nTim Hammermeister: Yeah\, then\, yeah\, this is a. \nTim Hammermeister: This is exactly what I’m talking about. So the dark part on this left image is the overlying water. \nTim Hammermeister: and you can see \nTim Hammermeister: we got partial penetration because of sand. In both of these images\, you know\, soft\, silty clay substrates. Sometimes it penetrates all the way to the \nTim Hammermeister: the top of the image. \nTim Hammermeister: And\, as you can see\, because this is all the light tan color. \nTim Hammermeister: Think this is more shadow in the one on the left than actually anoxic. \nTim Hammermeister: It’s well aerated again. That’s a reflection of the porosity of the sand and the \nTim Hammermeister: the water exchange. Yeah\, there’s some good ones. \nTim Hammermeister: There’s an example\, some of the gravel that Jay was talking about on the surface. \nTim Hammermeister: and you know you can spot various images\, and again the lower the penetration\, the denser\, the substrate. \nbgoeden: Yeah\, that was actually one of my questions\, because I was reviewing the studies again. And you had said in the document that the bottom was hard. \nbgoeden: hard sand bottom\, I think\, is what you called it. \nbgoeden: And I just was reflecting on that and trying to understand. Does it mean like it’s a consolidated sand that has to be sort of \nbgoeden: pushed apart by water jetting\, or is it loose enough that \nbgoeden: the material can be pulled into the equipment. It just the terminology struck me as really interesting. That just raised a question for me. I was like\, maybe I don’t really know. \nTim Hammermeister: It is\, it is relative. Generally. \nTim Hammermeister: when we see Sandy substrates they are consolidated just because they’ve been laid down by \nTim Hammermeister: the way they’re formed. It’s \nTim Hammermeister: there’s not water circulating from the bottom that would keep it unconsolidated. In general\, it’s it’s just the Water Exchange over the top\, and the way the sands\, and I’m not a \nTim Hammermeister: transport guy\, but maybe someone on the call. Would you know the way the sand is laid down? It’s much more Consolidated than \nTim Hammermeister: you know what you’d see on a dry\, sandy beach. \nbgoeden: Yeah\, and I also. \nTim Hammermeister: When you get into muddy areas\, when you see really unconsolidated stuff where it’s really soft gooey mayonnaise like \nTim Hammermeister: consistency. \nbgoeden: Yeah. So I also just dropped in the chat trying to presuppose one of Pat’s questions. So I did also look up the water year. During this study I think I have it matched up. But according to Dwr. This was a very dramatically wet year. \nbgoeden: It says\, the second place for State water runoff was after 1983. So apparently October 1\, 2016\, to September 30\, th 2017\, was very wet. So pat. If you had that question. I looked it up for you. \nbgoeden: and then Bob is asking whether or not the bed photographs are available. And yes\, they are\, Bob. They’re in the Benthic study by Newfields\, the full report\, and they are around page 40\, \nbgoeden: 4 of 117 in the Pdf. So it is available for you to think about. \nbgoeden: Look at all in that link that I added to the chat earlier in the meeting. \nPat Showalter: Thank you. Okay. Well\, I also see that Commissioner Gunther has a question. \nPat Showalter: You’re muted. \nAndrew Gunther: Thank you\, Pat. The message\, the message that you have \nAndrew Gunther: is\, does this have as its beginnings the remarks. \nAndrew Gunther: camera work in the 19 nineties that Noah was doing. Are you familiar with that. \nTim Hammermeister: Yeah\, it’s the same system. It’s just we. We refer to it as a sediment profile\, imaging camera instead of a \nTim Hammermeister: 3 months. \nAndrew Gunther: Yeah\, you’ve got. You’ve definitely improved the name. \nAndrew Gunther: Make sure I was associated with the same thing. Thanks. \nTim Hammermeister: Yeah\, it all. It all came from the same. We worked with Joe Germano prior to all. \nAndrew Gunther: Yeah\, okay. \nTim Hammermeister: It’s a small community. \nPat Showalter: All right. \nPat Showalter: I don’t see any more hands raised for questions. \nPat Showalter: So so now. \nbgoeden: Can I ask one more question because it. \nPat Showalter: Of course. \nbgoeden: This has puzzled me\, and I think Tim’s familiar with my question about this\, because it puzzled me last time. So with a Bakke study before after treatment comparison impact. However\, that term goes \nbgoeden: and you did the grid and the mining was either on the sample points or not. \nbgoeden: What I’m wondering is just trying to think about like the study and how its results are reported\, if \nbgoeden: and this is where I struggled with it before. So we had this conversation before. But I still sort of have this question\, which is\, if you’re doing a Bakke study\, and you have before after treatment before and then control? \nbgoeden: If the treatment doesn’t happen on the sample point\, does that \nbgoeden: truly reflect\, reflect the results? Or is it because the stamp\, the \nbgoeden: the treatment was sparse\, and it was like one episode of mining that’s considered a successful treatment. That’s what I like really struggled last time. And maybe you could just speak to that to help me with that struggle that I still feel like I have over the before after \nbgoeden: type project \nTim Hammermeister: Sure the key thing here is a habitat is not a point\, but an area. \nTim Hammermeister: So what we’re really looking at is the benthic habitat within the lease area and an area adjacent to it \nTim Hammermeister: to see if you know there are observable impacts. \nTim Hammermeister: Now\, again\, you know\, it’s it could be a measure of degree if \nTim Hammermeister: they mined every day for the the entire year between the study and got every \nTim Hammermeister: piece of sand out of the tree lease area. Certainly you’d see different results. \nTim Hammermeister: But just by the nature of how they’re mining through these lease areas\, the the habitat area doesn’t change. \nTim Hammermeister: So I mean\, originally the objectives were like was there impacts up to the foraging fish and stuff \nTim Hammermeister: by seeing how they are dredging through these areas kind of like what \nTim Hammermeister: Jay referred to. I think it’s strip mining. Since you have areas untouched and areas touched within the \nTim Hammermeister: within the overall habitat\, it recovers faster. And there’s still it doesn’t. \nTim Hammermeister: It doesn’t period of effect. \nTim Hammermeister: The habitat as a whole. \nTim Hammermeister: It the habitat is. \nTim Hammermeister: and especially in these high energy areas\, is what the habitat is. So you’re going to see \nTim Hammermeister: basically the same type of organisms coming back to colonize it. \nTim Hammermeister: And by its very nature it’s a colonizing habitat. \nTim Hammermeister: I know that sounds circular. But \nbgoeden: No\, it’s. \nTim Hammermeister: So a physical disturbance\, whether natural or \nTim Hammermeister: man-made disturbance in this type of environment\, it’s really hard to see a a change. \nTim Hammermeister: It would have to be a matter of degree. \nTim Hammermeister: And then\, you know\, I think we had a discussion before whether 12 months was \nTim Hammermeister: a long time or not\, but or too much time to see an impact. \nTim Hammermeister: Well\, that’s a kind of a different question of \nTim Hammermeister: exactly how quick it takes to recollonize it. \nbgoeden: Okay\, thank you\, Tim. I appreciate that little bit of expansion that’s helpful. \nPat Showalter: Okay\, it looks like Bob Battagio has a question as well. Are the grain size categories defined in the reports. \nPat Showalter: and Tim is on mood\, but he’s shaking his head. Yes. \nTim Hammermeister: Yes\, yeah\, we did a visual evaluation of the major grain size modes in the images. And then we had physical grain size samples collected along with the benta community. So the physical ones are a subset. And then the visual assessment on the digital images \nTim Hammermeister: is all 60 locations\, presidiary. \nBob Battalio: Yeah\, just to clarify. I was wondering if you had tabulated the actual \nBob Battalio: grain size ranges in millimeters or other dimensions like\, you know\, coarse sand. What is between certain \nBob Battalio: particular grain size? Yeah\, yeah. \nTim Hammermeister: Yeah\, we we have 4 game sites. \nTim Hammermeister: The full grain side distribution is in with the benthics\, community samples and the visual ones are much more of a dominated by this grain size\, type\, assessment. \nBob Battalio: Okay\, but you define what a course sand\, grain\, sizes and millimeters \nBob Battalio: in your yeah. Okay\, thank you. Thank you. \nPat Showalter: Excellent. Okay? So I think that does bring us to the end of the questions. So now we come to public comment on this\, and I’m wondering if anyone has some comments they would like to make \nPat Showalter: And also\, if if the miners would like to talk now that they would be welcome. \nPat Showalter: and they may come. \nPat Showalter: Go ahead. \nChristian Marsh: Commissioner showalter\, and and others. Thank you\, Christian Marsh. Again. \nChristian Marsh: I’m with the law firm as Stoll Reeves. I’m I’m not a bethic ecologist\, although I do \nChristian Marsh: have a specialty in endangered species\, critical habitats\, sequa and Nepa. \nChristian Marsh: I also began my career at interior in the office of water and science. So the science is incredibly important\, and I think the process is also important\, and I really want to commend \nChristian Marsh: on behalf of the the Sand Miners. I want to commend Bcdc. For this working group process has been very helpful. \nChristian Marsh: I wanted to just really briefly\, back up a little bit and and provide some context on the process as well. \nChristian Marsh: And also sand mining. So first\, st as Commissioner Showalter mentioned. \nChristian Marsh: we had provided yesterday a summary of of studies and evaluations that have been conducted\, of the effects of sand mining on bent\, thick habitats over the last 20 years. It’s really just a summary. I think the \nChristian Marsh: the original studies are all available. \nChristian Marsh: And those build on the earlier studies that Jay Johnson had mentioned in his presentation. \nChristian Marsh: I also want to mention that \nChristian Marsh: Bcdc. And again\, we commend Bcdc. For holding a two-day science panel. This is about 10 years ago that focused one day on Bethic habitats\, and the other day on coastal \nChristian Marsh: or us sand transport and supply. \nChristian Marsh: That was also helpful as well as \nChristian Marsh: conditioning as part of the permits\, and this is a condition from the Regional Board and Nymphs as well \nChristian Marsh: to form the Benthic Technical Advisory Committee. \nChristian Marsh: That Benthic tack was a bit like the Santac\, although administered differently \nChristian Marsh: but it was also comprised of all of the regulatory agencies\, and a representative from Usgs as well as the Sand Miners\, and that Beth attack is is \nChristian Marsh: who guided the new field study that you heard presented today from Tim Hamelmeister. \nChristian Marsh: obviously\, as you’re kind of hearing today. There’s a substantial amount of work\, and I think a lot more knowledge and understanding and certainty about the benthic habitats and the effects from sand mining than we might have from coastal geomorphology and and sand transport. \nChristian Marsh: But I would also note just for context\, that sand mining sand. Mining events in a given year are only comprised about one to 2% of the bay floor \nChristian Marsh: in each year. So while the sand mining effect might be significant in the specific discrete area. Mind\, it is quite marginal as you start looking at the the bay as a whole\, which is where \nChristian Marsh: I think the the Ams and new field studies \nChristian Marsh: come into play and then\, really just other than that I wanted to to introduce Dr. Chuck Hansen. He is a an expert ecologist. \nChristian Marsh: He was engaged by Mark Marietta and Lind to do the original studies and and the biological assessments for \nChristian Marsh: the last round of of permitting and leases\, and also this round of permitting and leases. \nChristian Marsh: And he might just have a couple of comments on on the study presentations today as well as as his own evaluation of the Benthic community over the years. So \nChristian Marsh: if I could just pass it to him\, I think that’s all we have. We’re certainly here and available for comments or questions. \nChristian Marsh: and and again\, really appreciate the commission\, and \nChristian Marsh: and Brendan in particular for for steering the the working group process. This has been very\, very helpful and informative. \nChristian Marsh: so with that I would pitch to to chuck if he has just any\, any comments whatsoever. \nPat Showalter: That’s great. And before Chuck starts talking I need to. \nPat Showalter: make a comment about a conflict of interest. I don’t think there really is a contract of interest. But I just want to let everybody know that I hired Chuck Hansen for several years while I was the project manager on the face investigation for Santa Clara Valley Water district. So we have a or we had a very close professional relationship. I\, however\, have not talked to him at all about this benthic investigation \nPat Showalter: and \nPat Showalter: So I’ve not been at all that. But I just wanted to let everybody know. I don’t. \nPat Showalter: Greg\, if you think there’s any recusal requirement at this point\, please let me know. \nPat Showalter: No\, alright\, thank you\, Chuck. It’s great to see you. \nChuck: Hey\, Pat\, very nice to see you again\, and \nChuck: I am still working on face for Santa Clara Valley. \nChuck: So your legacy carries forward. \nPat Showalter: Thank you. \nChuck: But in terms of the Benthic disturbance issues. With regard to sand mining\, I want to applaud the 2 presentations by Ams and Newfields. \nChuck: They bring new science to the forefront on benthic ecology and disturbance. \nChuck: and I’d like to turn the clock back 25 years to the point where we didn’t have that information. \nChuck: and this starts in about 20\,000. \nChuck: When the Sand mining community was starting to prepare for lease renewals by the Coastal or by the State Lands Commission. \nChuck: and we recognized through that process that the information we had available was really sparse. \nChuck: It was fragmented\, it was incomplete. \nChuck: And we really at that point I don’t think understood what sand mining was all about. \nChuck: and so the Sand Miners decided to \nChuck: enter into a collaborative effort with the State and Federal agencies. \nChuck: It was a 3 year program of data\, collection\, analysis\, interpretation\, and discussion. \nChuck: We met about quarterly for that 3 year period. \nChuck: and then in 2024\, we prepared a draft report. \nChuck: and the report was really intended to be a compilation of information on sand mining \nChuck: specific to Central Bay and Sassoon Bay. \nChuck: It was intended to provide to the agencies and all the parties a foundation of information. \nChuck: and the information that we tried to provide was reviewed by the agencies. It was also reviewed by an independent panel of scientific experts from around the world. \nChuck: and in that report we describe the methods for sand mining. \nChuck: We described the equipment. \nChuck: We had the miners for a year monitor in detail their locations where these worm trails are occurring. \nChuck: We looked at the frequency and the duration of each individual mining event. \nChuck: and through that process of better understanding the mining methods. \nChuck: we\, as the other speakers\, have said\, we identified that mining was really focused on \nChuck: sandy high velocity\, high disturbance areas within the bay. \nChuck: These are areas that are characterized by sand waves that epitomize the frequent and an ongoing disturbance \nChuck: through natural velocities and tidal action and other processes that occur within these areas where mining occurs. \nChuck: and by looking at those areas where mining occurs in the areas where it doesn’t. We found that mining really doesn’t occur in areas with fine colloidal sediments. \nChuck: And the reason for that is that that’s not the product that the miners want to actually sell. \nChuck: They’re looking for clean sand with very low percent of fines. And those are characterized by areas that are erosional \nChuck: that are frequently disturbed\, and the community that inhabits those areas\, as the 2 prior speakers say. \nChuck: are really characterized by a benthic community that has evolved and adapted to this kind of naturally occurring disturbance. \nChuck: They have high fecundity\, typically \nChuck: they have dispersal early life stages\, and they have the ability to fairly rapidly recolonize disturbed habitats\, and \nChuck: we then looked at studies that were conducted\, and\, as both Ams and and new fields point out\, there weren’t very many studies that were done specific to San Francisco Bay or the Delta. \nChuck: And so we needed to look basically worldwide \nChuck: to get whatever information we could from various research investigations and studies\, of dredging\, of other mining activity. \nChuck: of the use of suction dredges for harvesting Benthic clams\, you know\, whatever we could find\, we tried to pull together to really provide a a background \nChuck: of scientific information on the impacts of these kinds of mining activities. \nChuck: On the Benthe community. \nChuck: we tried to focus on similar areas\, having characteristics of the sand mining events in San Francisco Bay. \nChuck: and what we found was that in those studies they were all characterized by rapid recolonization. \nChuck: and that recolonization of disturbed areas could occur within a day or a year. \nChuck: We then\, you know. \nChuck: drew from that body of information of both the techniques and the methods of mining as well as the synthesis of information from other areas. Some conclusions that we thought were appropriate for sand mining within the Bay Delta system \nChuck: and one of our conclusions. This is obviously sand mining results in a temporary localized effect of penthic disturbance. \nChuck: We speculated that that would temporarily affect the benthic community characteristics\, but that the Benthic communities would rapidly recolonize those areas following a mining event. \nChuck: And we hypothesized from that body of information that there was really no long-term benthic impacts \nChuck: that were likely to occur. \nChuck: But we didn’t have site specific studies to really evaluate \nChuck: those hypotheses or those preliminary conclusions. \nChuck: And that’s what led to. I think the formulation of these specific studies that Ams and new fields have described. It was the effort to go out and actually conduct site specific studies on actual mining areas compared to controls both in Central Bay and in Sassoon Bay. \nChuck: to really better characterize using actual data from our system what the impacts are. \nChuck: And I think from both the Ams and the new field studies\, we’ve seen that \nChuck: the the study results are basically consistent and supportive of our earlier conclusions and hypotheses. \nChuck: and it seems like the mechanisms and the functions that they’re describing are very similar to what we drew from the scientific literature that was available at the time. \nChuck: And so I’m pleased to see that \nChuck: the early studies\, the synthesis and compilation of information\, has led to the actual site specific studies. We’ve got new information from both Ams and new fields that helps us better understand the impacts of sand mining and benthic disturbance\, an important \nChuck: environmental issues\, certainly for San Francisco Bay. \nChuck: And to better put this entire issue into a proper context. \nChuck: And so I appreciate the opportunity to provide some comments. \nChuck: But\, more importantly\, I appreciate the advancement of science that’s occurred over the last 25 years \nChuck: to help us better understand what’s actually occurring within this portion of the estuarine ecosystem. \nPat Showalter: Thank you. All right. So does anybody have questions for chuck or comments? \nAndrew Gunther: And I have one. \nPat Showalter: Yeah. Commissioner\, Gunther. \nAndrew Gunther: I have one question for Christian related to the letter that was submitted the summary letter\, and I \nAndrew Gunther: I think I know the answer to this question\, but I thought it best if I asked. And it’s about that\, I think there’s a missing word that makes a sentence confusing to me. So I just wanted to double check \nAndrew Gunther: on page 4 the second full paragraph \nAndrew Gunther: that says\, Benthic\, samples collected months after mining events exhibited densities. \nAndrew Gunther: and I think it’s supposed to say exhibited higher densities. \nAndrew Gunther: and I just wanted to make sure \nAndrew Gunther: before I insert a word that demonstrates my misunderstanding\, and I thought I would verify. \nPat Showalter: Page 4. \nChristian Marsh: Yeah\, it’s page 4\, second full paragraph. It says\, Benthic samples collected months after mining events\, exhibited densities of 2 \nChristian Marsh: amphipod taxa and total amphipods which suggests a positive correlation between disturbance and recolonization. \nChristian Marsh: That’s from. \nbgoeden: It was on one of the slides that Jay presented like that exact quote. \nChristian Marsh: Yeah\, that’s that is\, I think it’s \nChristian Marsh: I think it’s not saying higher or lower. I think it’s just \nChristian Marsh: stating that the densities that were revealed suggested a positive correlation. \nChristian Marsh: and but but Jay Johnson would probably be the best person to to comment. Actually. \nPat Showalter: Jay\, can you help us out with that. \njayjohnson: Yeah\, I’m I’m gonna try. I’d I’d probably use the word. Andy altered. \nAndrew Gunther: Okay that there was. It seemed to me that densities need to be modified in size. \njayjohnson: Right\, right? And I’d have to go back in to see where that statement or what statement we’ve actually made in the original report that that’s been\, you know\, pulled from. But what we saw and we talked about that in the Delta specifically is that the sites that had recently been mined. \njayjohnson: and and I’d have to go back to find out how recently was recent. But we were trying to do it within 6 months to a year would indicate that we actually saw. And and Tim made the same comment. You see\, increased species diversity \njayjohnson: that you didn’t see beforehand\, because Potamocorbula or Corbicula \njayjohnson: go away\, and they’re such an outstanding\, very effective competitor that as they get established they out-compete everything else. \nAndrew Gunther: Okay\, great. Then I thank you. I I just I wanted to make sure that I \nAndrew Gunther: I understood that because I had marked it as not being something that wasn’t necessarily but intuitive. \nChristian Marsh: Yeah. \nAndrew Gunther: So great. Thank you very much. \nChristian Marsh: But I appreciate that you’re you’re doing such a close reading\, though. Thank you. \nPat Showalter: Yes\, we can count on Commissioner Gunther to always do his homework. Very\, very good at that. Okay\, \nPat Showalter: So we’re in the public comment. I mean\, you know\, I’m asking for any public comments about this. We’ve had questions and and that’s good. But this is also a time to have discussion. So would anyone like to \nPat Showalter: share their thoughts with the with the group? \nPat Showalter: You know\, it’s obvious this isn’t a group of politicians\, because \nPat Showalter: there would be lots of hands raised. Okay\, even local politicians. \nPat Showalter: All right. So then I with that\, I think that I will pass it. \nPat Showalter: Annie. Is. Is there any comments you would like to make. \nAndrew Gunther: No other than I appreciated Chuck chiming in in terms of what we’ve learned over time. \nAndrew Gunther: and it really takes a long time to do this kind of work and to clarify certain things. And and of course\, we also see they’re always \nAndrew Gunther: in a highly variable environment like this. There are always outstanding possible questions that we might have\, and whether this was an appropriate year or not to do the analysis. And so there’s a there’s. There’s a lot of there are always some outstanding questions\, but I feel like this is an example of us directing \nAndrew Gunther: the studies that have refined our knowledge and greatly improved our ability to understand \nAndrew Gunther: what the sand mining activities are resulting in in the Bendic environment. It doesn’t mean we know everything\, but it it’s certainly a impressive\, in my opinion\, effort to jointly fact\, find in the community. And this is something that I always try and take a moment to point out that this kind of joint fact\, finding\, in my opinion\, is currently under attack \nAndrew Gunther: by the Federal Government\, who is rejecting \nAndrew Gunther: joint fact\, finding\, rejecting evidence\, and I think that it’s incumbent upon us if we’re going to work as a community of stakeholders to find answers and adopt policies that we base that on evidence that we can jointly develop together. And I think this is going to be an ever more important model\, as some communities in the United States appear ready to reject this method. \nAndrew Gunther: And so I’m very happy to be part of this here at Bcdc. See\, this is something we have done at the water board. It’s something that the consulting firms that we have just heard from do on a regular basis for us in the region. And I just I think it’s really an example of the right way to go about understanding things. \nPat Showalter: Yeah\, I would have to say ditto to that. And for instance\, one of the reasons I asked about the 2\,000. You know the \nPat Showalter: the the water year in 2\,000. I think it was 2\,008. It might have been another year. We were trying to tag fish \nPat Showalter: and the steelhead trout streams of Santa Clara County\, and we weren’t able to do that because there wasn’t any water\, so there wasn’t any fish\, because it was so dry. If that’s what I remember. Anyway\, there was a year like that when and when Chuck was involved\, where where we just we couldn’t do the scientific program because the you know\, the water wasn’t there but So \nPat Showalter: so sometimes these\, you know\, these water years in certain circumstances can make a big impact. So that’s why I wanted to ask about that. The other thing I wanted to confirm is that this collaborative report that Hanson mentioned is on our annotated bibliography. That’s I remember seeing it there\, and that’s I think I just want to confirm that with Brenda. \nbgoeden: Yeah\, Pat\, I don’t think we have pulled together an annotated bibliography for this work group. I think you’re thinking of the Ben\, the beneficial reuse work group where we did pull an annotated bibliography together. \nbgoeden: I will double check\, but that’s my recollection\, and I maybe am just not remembering that we’ve done that\, Jaime\, if I’m not remembering\, can you remind me if you think we have an annotated bibliography for Sand\, I think we have it for. \nPat Showalter: Or just maybe a list of of yeah. \nbgoeden: Yeah\, we can create one for you for sure. I just don’t think we’ve done that. But we do have the report. Here in the office. It’s about 2 inches thick \nbgoeden: and has a nice peer review section in the back\, so we can probably make that digital and post it. If people want to see it. \nbgoeden: Yeah\, \nbgoeden: yeah\, or at least a link to it. I don’t know how big of documents we can put on the website without me getting in trouble. \nbgoeden: yeah. And I guess the only other thing. Sorry. I’ll just. I have a quick mention of the next meeting if we’re finished\, but I don’t want to interrupt. If we’re not. \nPat Showalter: no\, I I think I just want to say ditto to the to what Commissioner Gunther said about the collaborative efforts. \nPat Showalter: They’re so powerful because they bring together information that people from a range of perspectives can evaluate. As you go forward and you can bring up\, you can hear the questions of different constituencies as you’re doing the studies to make sure that the studies are relevant for everybody involved. \nPat Showalter: and that means that in the end they’re much\, much more likely to have credibility for everyone and be useful for everyone. So I\, too\, am really happy to kind of be part of this trajectory\, and I do very much appreciate the \nPat Showalter: the sand miners and the scientists taking part. So I just wanted to mention that as well. \nPat Showalter: So yeah\, about the next meetings. \nbgoeden: Great. Yeah\, thank you. Pat\, I echo that sentiment\, too. It’s been several years worth of working together on science\, which has been fantastic. \nbgoeden: so our next meeting we had planned\, I think\, for July 15.th We are going to ask the Commissioners to see if we can alter that meeting date to accommodate a scientist who has some information about how sea birds use the central bay\, and I think what we’re looking to probably do is look at the fish entrainment issues\, the studies that are available on that and kind of the \nbgoeden: upper level critters \nbgoeden: connecting to this\, not sure if that will take the whole meeting. We might combine that part of the meeting with another section\, but unfortunately\, that week that we have it scheduled is a little tough\, for this particular person. It’s Julie Thayer out of the Fairlawn Institute. \nbgoeden: So \nbgoeden: yeah\, I think we may have 2 more meetings to wrap this up as our as our hope. So pat\, check your emails for Kat. She’s gonna come back to you\, Commissioner Gunther and Commissioner Nelson\, to see if we can \nbgoeden: make a date that works a little bit little bit different from the date that we had proposed. But that is basically it. We will be doing a quick \nbgoeden: well\, not a quick! A meeting on how sand mine\, how the sand that is mined is used in the region\, because I know the Commission had a lot of questions about that\, so we will touch on that as well or not. Touch on that. We’ll have a meeting that includes that information as well. \nbgoeden: So just know that that is still in the game plan. \nAndrew Gunther: So we are not gonna have that meeting as currently scheduled on July 15.th \nbgoeden: If we can get another meeting date we will move it. \nAndrew Gunther: Okay. \nbgoeden: But we have to figure out if we can get another meeting date. \nbgoeden: Yeah\, thank you. And I appreciate your being willing to meet this many times on this issue\, so appreciate that commissioners. \nPat Showalter: Okay? So if that would bring us to 6\, which is general public comment\, and that’s this is an opportunity that we always have in public meetings to allow anybody to talk about what is not on today’s agenda. So if there’s anyone who would like to speak to this group about something that isn’t on this agenda. Please raise your hand in zoom or \nPat Showalter: on the screen\, and we will call on you so you can share your thoughts with us. \nPat Showalter: I’m looking for raised hands. \nPat Showalter: Kat\, are you looking to? I do not see any. \nbgoeden: I don’t either. \nPat Showalter: All right. Well. \nPat Showalter: okay\, well\, thank you. I mean\, it is a joy and a pleasure and a privilege to be part of this scientific endeavor\, and I want to thank everybody for their attendance\, and with that this meeting is adjourned. \nbgoeden: Thank you. \nbgoeden: Thank you. Thanks everyone for joining. \n\n\n\n \n \n \n \n \n Learn How to Participate\n Bagley-Keene Open Meeting Act\nAs a state agency\, the Commission is governed by the Bagley-Keene Open Meeting Act which requires the Commission to: (1) publish an agenda at least ten days in advance of any meeting; and (2) describe specifically in that agenda the items to be transacted or discussed. Public notices of Commission meetings and staff reports (as applicable) dealing with matters on the meeting agendas can be found on BCDC’s website. 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URL:https://www.bcdc.ca.gov/event/may-21-2025-sand-studies-commissioner-working-group-2/ CATEGORIES:Sand Studies Commissioner Working Group END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/Los_Angeles:20250318T130000 DTEND;TZID=America/Los_Angeles:20250318T150000 DTSTAMP:20260624T062646 CREATED:20250304T234453Z LAST-MODIFIED:20250421T182109Z UID:10000269-1742302800-1742310000@www.bcdc.ca.gov SUMMARY:March 18\, 2025 Sand Studies Commissioner Working Group DESCRIPTION:Meeting Agenda \nPresentations: \n\nSand budget update Lester McKee\nSand budget update mining team comments\nSand Studies: what we know\, what we still don’t know\, and what we learned along the way\n\n  \n  \n \n \n \n \n Video Recording URL:https://www.bcdc.ca.gov/event/march-18-2025-sand-studies-commissioner-working-group/ CATEGORIES:Sand Studies Commissioner Working Group END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/Los_Angeles:20250205T130000 DTEND;TZID=America/Los_Angeles:20250205T150000 DTSTAMP:20260624T062646 CREATED:20250127T204149Z LAST-MODIFIED:20250205T205523Z UID:10000266-1738760400-1738767600@www.bcdc.ca.gov SUMMARY:February 5\, 2025 Sand Studies Commissioner Working Group Meeting DESCRIPTION:Meeting Agenda URL:https://www.bcdc.ca.gov/event/february-5-2025-sand-studies-commissioner-working-group-meeting/ CATEGORIES:Sand Studies Commissioner Working Group END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/Los_Angeles:20241122T090000 DTEND;TZID=America/Los_Angeles:20241122T110000 DTSTAMP:20260624T062646 CREATED:20240716T205519Z LAST-MODIFIED:20251119T180744Z UID:10000188-1732266000-1732273200@www.bcdc.ca.gov SUMMARY:November 22\, 2024 Sand Studies Commissioner Working Group DESCRIPTION: URL:https://www.bcdc.ca.gov/event/november-22-2024-sand-studies-commissioner-working-group/ CATEGORIES:Sand Studies Commissioner Working Group END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/Los_Angeles:20240904T100000 DTEND;TZID=America/Los_Angeles:20240904T120000 DTSTAMP:20260624T062646 CREATED:20240716T205250Z LAST-MODIFIED:20240910T181626Z UID:10000187-1725444000-1725451200@www.bcdc.ca.gov SUMMARY:September 4\, 2024 Sand Studies Commissioner Working Group DESCRIPTION:Meeting agenda \nUnderstanding impacts of bay sand mining on transport in San Francisco Bay presentation \nPublic comment letter \n \n \n \n \n \n Meeting recording & transcript\n \n \n\nTranscript\n\nLet everyone in\, OK? \nIt looks to me like we have our independent science panel \nmembers who were planning to be here and it looks like we have \nthe full just double checking complement of the sand mining \ncommunity members. \nSo and then we have quite a few members of the public interested \nparties. \nThank you all for joining. \nSo I think we are ready to get started when you are Pat. \nOK\, well\, I’m\, I’m certainly ready. \nMy name’s Pat Showalter\, and I’m ABCDC Commissioner and the chair \nof this sand mining subgroup. \nAnd I want to welcome everybody to this educational meeting and \nwe’re gonna hear 2 great presentations and also have time \nfor questions. \nSo with that\, I’ll I’ll let Brenda talk about our ground \nrules. \nYeah\, Thanks\, Pat\, and welcome everyone. \nSo for those of you who have been here before\, you know the \nground rules\, but basically this is a fairly open forum to \ndiscuss and learn about the sand mining studies that we’ve been \nworking on for the last\, I guess\, three to five years\, a \nlong time and are grateful for all the work that folks have \nbeen doing. \nSo if you want to join in the conversation\, you’re welcome to \ndo so. \nThe way the meeting will run is we’ll have a presentation\, we’ll \nhave a moment for the OR period of time for the sand miners to \nprovide comments on the presentations. \nWe will move to commissioner questions or thoughts. \nAnd at that point in time\, if you have things that you would \nlike to add or questions\, please feel free to raise your hand and \nwe’ll call on you. \nWe do have a schedule we’re trying to stick to so we can get \nto both presentations today\, but I think we have plenty of time \nand there is a public comment period at the very end if you’d \nlike to make a statement of public comment beyond just \ndiscussion and questions. \nAnd I’m going to quickly just jump into my very quick \nobligatory presentation for contact setting for folks who \nmay not have been here. \nI will do that hopefully quickly because I think most of you have \nseen this before\, but just to make sure everybody is on the \nsame page and\, and I just need to find my presenter mode real \nquick\, which\, ah\, there it is. \nIt’s moved. \nOK\, All right\, so we are here today. \nI’ve got the wrong date on my calendar on my cover sheet\, but \nwe are today on September 4th to talk about the sand mining \nstudies. \nWhere we’ve been so far is back in 2015 as part of the BCDC \npermitting process. \nLinden Martin Marionetta\, which was formerly Hanson Aggregates\, \nprovided $1.2 million to study sand mining impacts on the \ncommunity\, excuse me\, on the Bay\, not the community\, sorry. \nWe formed a Sand Technical Advisory Committee\, which was \nmade-up primarily of the regulatory and resource \nagencies. \nHowever\, Baykeeper and the Coastal Commission\, which is not \na Regulatory agency in this setting\, but a commenter\, joined \nthe group because of their high interest in the studies and \npotential effects of mining. \nSo that group looked at management\, develop management \nquestions\, did study scope development\, posted a request \nfor proposals and reviewed proposals. \nWe also have our very esteemed independent science panel\, which \nthree members are here today. \nSo we have Craig Jones from Integral\, we have Bob Battaglio\, \nformerly of Environmental Sciences Associate. \nWe have Dave Scholhammer\, USGS Emeritus. \nAnd we also had Paul Work\, who was also of USUSGS at the time\, \nand also John Lazier\, who’s the Director of Oceanography at the \nBodega Marine Lab\, University of Davis. \nThey reviewed the proposals\, revised the scope because \nthey’re\, as the proposals came in\, there was some clear ways \nthat we could make more efficient and coordinated \nstudies. \nWe identified this\, they identified the science teams and \nworked with the teams as they completed the studies. \nAnd then they developed the findings report with Santech. \nCurrently\, we are in a commissioner working group. \nWe’re on the third of four to try to help the commissioners \nground themselves in science and this group is providing \nleadership to the larger Commission. \nOur next steps are the Sequa NEPA process with State Lands \nCommission and potentially the Army Corps of Engineers on NEPA \nand then permitting through the various agencies. \nAnd so the study questions that we were working to address are \nlisted here. \nI’ll just read the overview questions of sand mining at \nexisting lease areas at permitted levels having a \nmeasurable or demonstratable impact on sediment transport and \nsupply within San Francisco Bay. \nWhat are the anticipated physical effects of sand mining \nat permitted levels on sand transport and supply within San \nFrancisco Bay in the outer coast? \nAnd are there other feasible alternatives to sand mining or \napproaches to consider in San Francisco Bay? \nThe studies focused on the physical processes. \nThe biological issues are associated with other studies \nand investigations\, some of which have been completed and \nothers are in the literature. \nAnd so I’ll just move on from here to our next slide. \nSo quickly just reminding us of the lease areas. \nSo Martin Marionetta is the primary or only minor within \nCentral San Francisco Bay. \nThe areas in purple are the lease areas. \nThere are four lease areas with 9 parcels. \nThis lease area in Raccoon Strait is not mined. \nThe leases are from State Lands Commission in this case and the \nmajority of the sand mined in this area is primarily coarse \ngrain. \nThere is also fine grain sand that is mined primarily here. \nPresidio Shoals area. \nAnd then the Sassoon lease is the other primary mining site in \nthis project. \nSo this is mined by Sassoon Associates\, which is a \ncombination of Martin Marianetta and Linda Marine. \nThe mining in this area is up to 45 deep feet deep. \nIt is again a lease from California State lands and it is \nprimarily fine grain sand. \nThat’s where most of the mining occurs. \nAnd the last lease area\, which has the smallest amount of \nmining at this point in time is Middle Ground Shoal lease area. \nIt is mined primarily by Linde Marine. \nThis area is up to 30 feet deep. \nIt’s adjacent to an island\, a very small island called Middle \nGround Island. \nIt’s a private lease. \nAnd this is\, again\, fine grain sand. \nThe equipment used is hydraulic dredging. \nSo Martin Maria has a suction dredge piece of equipment. \nHere is the drag head for Martin Marionetta’s equipment. \nAnd Linde Marine uses a suction pipe\, slightly different \nequipment\, both hydraulic and both are equipped with a fish \nscreen on the outside of the pumping mechanisms to reduce \nentrainment. \nIt’s important to frame the mining activities in that this \nmining is done primarily well\, actually 100% for construction \naggregate\, aggregate. \nIt is not done for navigation dredging. \nSo this is not a navigation. \nThese are not navigation projects. \nIt’s not generally considered a beneficial reuse because \nbeneficial reuse is generally considered a waste product \nthat’s being reused for other purposes. \nIt occurs year round and there are no work windows\, but the \nfish screens that I mentioned previously reduce entrainment \nwith the on the intake pumps. \nSo the mining basically occurs on an as needed basis in both or \nall three projects an order is filled with the grain size that \nis required for the jobs. \nAnd so in this industry\, the sand mining closely follows the \nconstruction industry and trends and mining tends to be repeated \nin the same areas\, in the same on the same lease areas because \nof this need for a specific grain size. \nIn the last two meetings\, we had four presentations. \nThe first one was the independent Science panel’s \nfindings report\, the overview of the findings. \nAnd then we had University of Texas at Austin provide San \nProvidence and Aging report. \nDelterra’s last meeting did a volumetric change analysis and \ntransport presentation and San Francisco Estuary Institute \nprovided a sediment and sand budget review of their work. \nToday we have basically two more. \nI think these are our final studies if I’ve got that \ncorrect. \nSo is sand mining at existing leases at permitted levels \nhaving a measurable or demonstratable impact on sand \ntransport with San within San Francisco Bay? \nSo Michael McWilliams\, formerly of Anchor QEA and Brian Beaver \nworked on this document and they have the sand transport modeling \nreport and presentation. \nAnd the second presentation today is same question but \nlooking at more or less sand supply and the changes within \nthe bethemetery of San Francisco Bay. \nAnd that will be presented by Bruce Jaffe\, formerly of US \nGeologic Survey and he is retired but back for on demand. \nI’ve had a few questions from folks about where to find past \ninformation\, so I just thought I’d try to briefly run you \nthrough where you can find this on the website. \nToday is September 4th. \nOur last planned meeting is November 22nd\, right before the \nThanksgiving holidays\, so we’ll hope you all be there. \nThis is a snapshot of BCD CS landing page on our website. \nTo find the old meetings\, you go to meetings and then you toggle \non down. \nIf I can get my computer to share it to the meeting area and \nyou can look at it in a list view or a calendar view\, but you \ngo to the date where the meeting was. \nAnd if you click on that\, that should get you to this page \nwhere you’ll find the agenda and the presentations. \nAnd for August 21st\, we don’t yet have the transcripts up\, but \nthere will be a transcript of all of the meetings. \nSo you can actually watch the meeting if you missed it. \nSo that is my quick context setting. \nI’m gonna stop sharing and turn it back over to you\, Pat. \nThank you. \nAll right\, so next\, do we have any? \nFirst of all\, do we have any questions related to this \ncontext setting from the commissioners? \nThis Andy or Barry\, do you have a question? \nOK\, seeing none what about other people who are participants? \nWe have 42 right now Wow\, that’s great wonderful interest. \nI’m looking for raised hands. \nOK. \nAnd I’m not seeing any. \nSo I think Kat\, is that correct? \nCorrect me if that’s not anyway. \nSo I think that what’s what that means is we want to go on to the \nmain presentations for this meeting. \nWhat are the impacts of sand mining on on sand and transport? \nAnd Michael McWilliams of Flow W is going to I know Michael \nMcWilliams is going to make a presentation and after that we \nwill hear from the sand miners. \nSo Michael\, would you like to get started? \nGreat\, thank you. \nPat\, let me share my screen here\, hopefully. \nOK\, does everybody see that? \nOK\, yes\, OK\, perfect. \nSo this is a study that I did a couple years ago while I was at \nAnchor QEA with Aaron Beaver\, and I’m just gonna give kind of \na high level summary of what we did with the hydrodynamic and \nsediment transport modeling. \nI think it’s really great that Bruce is following this \npresentation with some of his work looking at longer term \nbathymetric data sets because we’re both kind of asking and \ntrying to answer the same question with two different \nlines of evidence and really kind of looking at two different \ntime scales. \nSo the computer model is really looking at a one year time frame \nto understand\, you know\, what’s happening where the sediment’s \nmoving on a\, you know\, shorter time scale. \nAnd then\, you know\, we’ll see from some of the work that Bruce \nis gonna talk about with the longer term cumulative effects \nof that is looking at the longer term bathymetric change record. \nBecause from a\, from a modeling standpoint\, it becomes not as \ncomputationally feasible to look at\, say 30 years of change\, but \nwe can look at\, you know\, individual years of change. \nAnd so one of the things I think that was really great about \nthis\, the way the Stan study was structured in general\, is there \nwere a whole bunch of different scientific studies using \ndifferent approaches to try and answer different parts of the \nsame question. \nAnd then\, you know\, we can learn a lot from how those different \napproaches corroborate or or don’t corroborate each other. \nSo the\, the focus of the presentation today is going to \nbe on the sediment transport modeling that we did for\, for \nBCDC as part of this SAN studies. \nSo I’ll begin by reviewing the model scenarios and the analysis \napproach and then I’ll talk about the results both in \nSassoon Bay and Central Bay. \nAnd then I’ll give kind of a synthesis of what the the \nprimary findings of the the modeling are. \nSo first talking about the sediment transport model \nsimulation. \nSo we have a A3 dimensional hydrodynamic sediment transport \nmorphologic wave model that we’ve developed over the last \nalmost 25 years now of of San Francisco Bay that extends from \nPoint Reyes out here in the Pacific Ocean all the way \nthrough all of San Francisco Bay and the Delta. \nIt includes\, you know\, all of the main Delta tributary \ninflows. \nIt includes the temporary barriers and operable gates in \nthe in the Delta and includes all the different agricultural \ndiversions representative of agricultural diversions and \nreturn flows. \nAnd then as part of this study\, we used the work that SFBI had \ndone on looking at all the inflows to the Bay and we added \nall these blue arrows around the Bay or different small tributary \nwith sediment inflows that we added to the Bay because we \nwanted to incorporate all of the potential sediment sources. \nThe model runs with the tides at the ocean boundary and then we \nhave\, you know\, water and sediment coming in from from all \nof these these tributaries. \nWe have an initial sediment bed in the Bay that we’ve developed. \nI think there’s about 3000 or so different sediment samples \naround the Bay that we’ve spatially interpreted\, spatially \ninterpolated to get the initial grain size. \nAnd then we have used various different information on grain \nsize from the the tributaries to figure out and estimate what the \ngrain size of the sediment coming in from each of the \ntributaries are. \nAnd then lastly\, we looked at the data from the sand mining to \nunderstand what the\, the sediment properties of the sand \nfrom the sediment mining was. \nAs all this doc\, all this information is documented in \nthe\, the modelling report that we provided to BCDC and the\, \nthe\, the\, the sand mining panel. \nSo I think if you want any additional details on\, on some \nof this\, a lot of that is\, is documented in that\, in that \nreport. \nSo we run this model for with a 92nd time step. \nSo it cycles through\, you know\, every 90 seconds it calculates \nall of the\, the transport of water and salinity and sediment \nacross the whole Bay delta system. \nAnd then this incorporates the effect of winds and tides and \nall of that in into the model simulations. \nSo the goal of the model scenarios was to investigate how \nsand mining effects sand transport. \nAnd So what we did to do this is we developed basically 2 sets of \nparallel conditions. \nThe first is basically the existing bathymetry based on the \nsurveys we have from after the sand mining was completed. \nBasically all of the existing bathymetric surveys are \nrepresentative of the conditions with sand mining. \nAnd then we wanted to come up with an estimate of what the Bay \nwould look like if we didn’t have sand mining. \nAnd since we are simulating one year of simulations\, what we did \nis we developed a kind of an alternative condition where we \nadded back the amount of sediment equivalent to the \nannual volume of sand mined from the Central Bay and from Sassoon \nBay. \nSo essentially we got all the records from the sand mining for \nfor where the sediment was mined with the sediment material was \nand we basically added that material back into the Bay. \nAnd that does two things that\, that that affect the\, the \ntransport #1 any\, you know\, when you add that sand back\, any \ndepressions or\, you know\, deepened areas that are there \nbecause the mining occurred\, you’re putting sediment back \ninto that spot. \nAnd #2 you have that sediment then back on the surface of the \nbed\, which is able to move around. \nAnd so we wanted to look at specifically what happened to \nthat sediment that was mined when we put it back. \nWhere did it transport? \nAnd then\, so we tracked that sediment different from all the \nother sediment. \nAnd then we also wanted to just look at the total amount of sand \ntransport. \nBasically\, if we had that sand\, that sediment back in the Bay \nand we simulated a wet year and a dry year\, how how different is \nthe sand transport? \nAnd you know how big is the signal of where the transport is \ndifferent because you added that sediment back or\, or you or you \ndidn’t. \nSo you kind of have basically 2\, two different conditions. \nThat one is that it’s a little bit\, in some ways a little bit \ncounterintuitive to get to get your head around. \nBut the existing condition is with site and sand mining. \nAnd then the kind of the artificial condition that we \ndeveloped this scenario is the without\, without sand mining. \nAnd we tried as as much as we could to represent the grain \nsize and spatial distribution of the the sediment that we added \nback. \nSo by by running a wet year and a dry year with these two \ndifferent geometries\, which are only different by\, you know\, \nadding that sediment back into the central Bay and adding that \nsediment back into Sassoon Bay\, we can evaluate where that \nsediment that was mined was transported over that year. \nWe can compare changes in the in the\, the thickness of the \nsediment bed between the two scenarios. \nAnd we can also look at it any given cross section\, how much \nsediment passed through that cross section. \nSo if we put that sediment back into the mining area\, does it \nchange the transport of sediment\, you know\, upstream or \ndownstream from there? \nSo they’re kind of pretty focused questions looking at you \nknow on on the time scale of one year what what was happening. \nSo we looked at two different years. \nWe looked at a wet year and we looked at the period between \nJune 2018 to June 2019. \nAnd we looked at a critical year\, which is the driest of the \nfive water year classifications in California between June 14th \nand June 2014 and June 2015. \nAnd these periods were picked partly due to the availability \nof data on the sand mining that occurred in those years and \npartly just to to capture a wet year and a dry year. \nSo you can see here in the wet year this is showing the delta \noutflow in thousand CFS. \nWe see very high outflows in you know\, 175\,000 CFS in the the \nsummer and then in the dry year the the peak was just over \n50\,000 CFS and it was relatively small. \nSo we can see a very big difference in the total amount \nof of water flow in the wet year and in the dry year. \nAnd then you know\, there’s an associated difference in the \nsediment supply from those those two different years at all. \nSo for each of these conditions\, we simulated the baseline \ncondition\, which is basically you know how conditions are \nright now with the historic sand mining that happened in that \n2018-2019 and then the the baseline conditions for the 2014 \nto 2015. \nAnd then we have the equivalent scenarios for both of those \nwhere we’ve taken the the initial bathymetry and added \nback\, you know\, a one year annual amount of of settlement \nthat was mine. \nSo this shows the differences in the two scenarios. \nSo basically this is an estimate of the amount that was that was \nadded back for the mining. \nI think this is for the wet year. \nSo you can see basically here that just here in Central Bay \nadding sediment back primarily\, you know\, in in these these two \nareas here. \nAnd then there’s some sediment added back here along Ships \nIsland in Tassoon Bay and a tiny bit here at this middle ground \nShoal lease area. \nSo from a computer modelling standpoint\, everything about \nthese two scenarios is exactly the same. \nThe tides are the same\, the winds are the same\, the waves \nare the same. \nThe only difference is in one of them we’ve added back this \nadditional sediment to the to the model and the other one is\, \nis without that sediment. \nSo we can then run the this computer simulation for a year \nand we can understand how the transport of of sediment is \ndifferent whether or not that that sediment is put back in. \nSo we’ll go through the the two different areas separately\, \nfirst Sassoon Bay and then Central Bay. \nSo this is the the same kind of figure we just looked at here. \nFor Sassoon Bay. \nThis is showing the sand that’s added back into the model before \nthe initial simulation and then this shows at the end of the one \nyear. \nWhere that sand was transported. \nSo in the high outflow year\, we can see the sand that was \ninitially put here is largely transported\, you know\, back and \nforth in the the main ship channel there’s a little bit of \neastward transport. \nPast Chips Island\, there’s transport in Sassoon Bay and \nthen generally the\, there’s\, we weren’t seeing very much \ntransport at all of that sediment from Sassoon Bay past \nthe Bulls Head Shoal over here at\, at Carquena Straight. \nSo one of the things that that you do see\, you know\, there’s a\, \nthere tends to be a convergence area of sediment here because \nyou have the deeper\, the deeper area here in Carquena Straight\, \nyou get some gravitational circulation and\, and return \ncurrents near the bed. \nAnd then in the low out flow year\, the picture looks pretty \nsimilar. \nGenerally a lot less transport of that sediment away from the \nthe sand mining areas. \nBut one thing that you can see from this is that the\, you know\, \nthe effect of the sand mining in Sassoon Bay over this one year. \nIs pretty localized to\, you know\, this\, this main channel \narea of Sassoon Bay. \nIt’s not\, it’s not having an effect upstream very much and \nit’s not having an effect really past\, past pull central. \nWe can look at the predicted bed thickness across the entire \nSassoon Bay between the two scenarios at the end of the \nyear\, basically anywhere that’s white on this map. \nThis is for the high\, high outflow year is less than .1 \ncentimeter\, so like 1mm difference. \nSo basically what you see in most of Sassoon Bay\, you really \nhave very little effect of the sand mining that that’s showing \nup. \nThe biggest effects are\, you know\, really localized to the \nsand mining areas\, which which shows that that that the mining \nis not having a big effect on\, on deposition across the rest of \nof Sassoon Bay. \nAnd then if we look at the low outflow year\, it looks it’s a \npretty similar picture. \nMost of the Soon Bay we have virtually no difference in the \nthickness of the sediment bed at the end of the year. \nAnd the primary differences are\, are\, are still focused in these \nareas where the mining occurred. \nSo\, you know\, we put that sediment back in\, in the the no \nmining case and that sediment is still largely\, you know\, in that \narea and hasn’t moved that much. \nSo that’s telling us that the the effect of the mining is \nreally very localized into soon Bay to the to the mining areas. \nThen we also\, and this is pretty similar to the some of the work \nthat Mick van der Wagen and the the tires group probably showed \nat one of the previous meetings. \nWe wanted to look at the\, the sand transport vectors of the \ndirection and magnitude of sand transport from\, from the model \nsimulations. \nAnd so there are arrows on this figure here on the left showing \nthe sand transport during the high outflow year. \nAnd they’re color-coded based on the\, the direction. \nSo if they’re red\, they’re\, they’re basically pointing \nseaward. \nAnd if they’re blue\, they’re\, they’re\, they’re pointing \nlandward. \nAnd so one of the things you can see is there tends to be some \nlandward kind of back towards Sassoon Bay\, transport of \nsediment along the bed here in Karkina Strait. \nAnd this is one of the things that we we highlighted in our \nreport is you do get this convergent zone of sediment \ndeposition here at Bulls Head Shoal. \nThat could also be another place where you know\, there may be \npotential for for sand mining where where you have this \nalready build up of sediment that’s causing a need for fairly \nfrequent dredging by the Army Corps of Engineers in this \nBullhead Shoal region. \nBut it’s another area where the sand is is largely converting. \nWe can see here the predicted change in sand transport without \nmining. \nThis is basically just the difference in transport. \nWe can see the Red Arrows here along Chips Island and a little \nbit here in the the ship channel. \nThose are the areas where we’re seeing the biggest difference \nin\, in\, in sand transport. \nAnd then throughout the most of the rest of Sassine Bay\, you \nknow that you don’t really see much difference. \nAnd this is so real. \nThis is really telling us the same thing as what that other \npicture was showing\, which is that the effects of the sand \nmining at Chips Island here in Sassine Bay are relatively \nlocalized and they’re not having a big effect on on sand \ntransport in in the rest of Sassine Bay. \nSo we looked at a bunch of different cross sections in the \nWest here starting at Venetia Bridge and in the east\, the \nSassoon 1\, which is right at the edge of of Chips Island. \nAnd you can see here at the Sassoon cross sections 1-2 and \nthree\, which are the ones very long Chips Island. \nThere’s a pretty big difference in the amount of sand flux \nbetween the mining and without mining. \nIn particular at the Sassoon too\, which is right in the \nmiddle of the the mining area in Chips Island. \nThere was\, you know\, more downstream transport of sand at \nat that section in particular without mining than there was \nwith mining. \nThe percentage is very high and that’s partly because in the dry \nyear the the sediment flux was very\, very small in the baseline \ncondition. \nSo the magnitude of transport increased some\, but it ends up \nbeing a high percentage because the baseline value is like very \nclose to to 0. \nSo but what you do see here is that Sassoon 4-5 and Venetia \nBridge and Sassoon cut. \nSo in this whole rest of the portion of Sassoon Bay\, the \neffects of the sand mining on\, on sediment\, on sediment \ntransport on sand transport is\, is very small. \nSo all\, all these different ways of looking at it are really kind \nof showing the same thing for Sassoon Bay\, which is that the\, \nyou know\, the effects of the mining is pretty localized here \nalong Chips Island. \nAnd then the rest of the same Sassoon Bay doesn’t have as much \nfact effect of the of the sand mining on transport. \nSo we do the same analysis for Central Bay. \nThis is showing the regions where sediment was added back \ninto the the model to come up with the estimate of what the \nwithout sand mining conditions would look like. \nAnd then we can show basically where that sand that we put back \nwas transported after one year during a high outflow year and \nduring a low outflow year. \nSo that the sand that we we put back in Central Bay is largely \nstays within Central Bay. \nThere’s some transport of that sand out through the Golden \nGate. \nThere’s some transport of that sand\, you know\, a little bit \nupstream here along Angel Island and between Treasure Island and \nAngel Island. \nBut the effects are\, are pretty localized to the Central Bay and \nthen you know\, the\, the transport out out the Golden \nGate. \nIf we look at the predicted bathymetric difference between \nthe\, the\, the bed at the end of the one year in the two \ndifferent scenarios\, most of the difference kind of the red \ncolors that are up to 10 centimeters are focused in the \nareas where the mining occurred\, which which makes sense\, right. \nSo we put that sediment back into those areas. \nThere’s the sediment bed is still thicker at the end of one \nyear in those areas\, most of the areas are you know this white \ncolor is .1 centimeters\, so 1mm. \nSo anywhere that’s white\, we’re not really seeing any difference \nat the end of of one year. \nThe Gray is\, is .1 to 1 centimeters. \nAnd then so you can see generally the effect of the\, the \nsand mining is still focused in the\, in the the mining areas. \nBut we do see some\, some more sediment moving out the Golden \nGate here and a little bit moving up into this part of \ncentral Bay in\, in the high output year. \nAnd then a similar picture here for the\, this is for the low \noutput year. \nSo we can see in general the sediment staying pretty close to \nwhere we put it\, but there’s some of it is\, is being \ntransported out in the Golden Gate. \nIf we look at the maps of the the sand fluxes\, it’s it’s\, you \nknow\, it’s relatively complicated circulation \npatterns. \nWe see sediment fluxes from central Bay out the Golden Gate. \nWe also have these kind of return circulation cells along \nthe sides that I think you also can can see from some of the \nwork that that Deltares showed. \nAnd then the difference in in flux between the two different \nscenarios. \nThis is the high output year on the top and the low output year \non the bottom. \nThe biggest difference we’re seeing is that there’s a little \nbit more flux of sediment out through the Golden Gate in both \nof these conditions\, which is because we have more sand \navailability that we we put into the Bay for that year. \nWe’re seeing more transport out the Golden Gate. \nIf we look at it as a percentage without\, without sand mining\, we \ndo see a larger flux of Westford\, Westbrook\, westward \nsand transport out through the Golden Gate. \nIt was about 142% higher in the wet year and about 50% higher in \nthe the dry year in terms of the amount of sediment that that was \npredicted to move out through the Golden Gate. \nAnd without sand mining\, we see a little bit less sand transport \nthrough Raccoon Straight. \nSo there’s a there’s less of a net transport through Raccoon \nStraight in the scenarios where we have added back the sediment \nhere. \nAnd then there’s really not very much effect here at this line \nhere between Angel and Island and Treasure Island or across \nwhere the\, the Bay Bridge is. \nSo this is showing us that largely the biggest effect of \nthe mining that we’re seeing in the model is without sand \nmining. \nWe see a larger flux through the\, the Golden Gate and a a \nsmaller flux through Raccoon St. \nNow I’m gonna move on to just some of the the some of the \nprimary findings\, which is summarizing what we saw from the \nmodeling in the context of some of the other work that the \nstudies did. \nWhat we’re seeing in Sassoon Bay is largely episodic westward \nsand transport. \nSo when we have periods of very high elevated delta outflow\, \nthat appears to be responsible for most of the sand transport \nthrough Sassoon Bay to San Pablo Bay. \nThe sand mining reduced the predicted westward transport of \nsand\, but those effects were pretty limited to the area right \naround Chips Island. \nDuring the one year periods we looked at\, we didn’t see any \neffects of the mining in Sassoon Bay extending past Venetia \nBridge. \nThis could be\, this could be an artifact of the fact we are only \nlooking at one year. \nAnd if we had looked at\, you know\, simulating 2345 years that \ncould have propagated further West. \nBut across one year\, we largely didn’t see any effects of the \nSassoon Bay sand mining extending past Venetia Bridge. \nAnd part of that may be that there’s another\, you know\, \nthere’s a pretty high area of deposition here at at Bulls Head \nShoal where where you have the convergence of of sand \ndeposition. \nAnd that may be limiting the effect of the the sand transport \npropagating further downstream. \nBut it would probably require a longer multi year simulation to \ntry and understand how long it would take to propagate that \nthat mining effect further downstream. \nThis is the conceptual model from Bob Battaglio here showing \nthe the transport of sediment out the Golden Gate. \nAnd then you can kind of see these cells moving sediment back \nalong along the shoreline. \nWe had a net predicted sand flux from the model out of the Golden \nGate to the Pacific Ocean. \nWe also had these cells predicting some transport back \ninto the Bay in in some periods. \nWe saw that the sand mining was predicted to reduce the \ntransport of sand out of the Golden Gate and it didn’t have \nvery much effect\, you know\, east of the mining at either Angel \nIsland or\, or at the Bay Bridge. \nSo we\, the model is suggesting that that removing sand from \nfrom the central Bay potentially does reduce the sand available \nfor the San Francisco bar and the other beaches. \nBut because we’re only again looking at one year and the \ntransport times and distances are relatively big\, you know\, \nit’s hard for us within the model simulation to to come up \nwith it a direct relationship between the mine sand volumes \nand how that affects\, you know\, sand volumes that make it to \nOcean Beach. \nSo I think those are areas where some of the other lines of \nevidence such as the bed forms and the longer term bathymetric \nchange may be more more useful for for answering some of those \nkind of longer term morphologic changes. \nAnd that’s what we have for the presentation. \nBut I’m happy to take any questions that you have. \nOK. \nWell\, first we usually go with Commissioner questions. \nSo Commissioners\, do you\, do you have any questions? \nIf so\, please speak up. \nYeah\, Pat\, I’ve got a couple of questions. \nGreat. \nCan you find my digital hand here too raise it. \nSo thanks so much for this presentation. \nI’m first question is we flip back and forth in our language \nbetween sand and sediment and\, and I want to make sure that I \nunderstand that\, that when you’re using the term sediment \nin this presentation\, you were still referring to sediment of a \ngrain size that we would call sand. \nYeah\, yes\, that\, that was my probably sloppy language in that \ncontext. \nBut yes\, we\, we are modeling the full range of sediment sizes\, \nsilts and flocks and fine sediments. \nBut everything that we’re showing in this is only focused \non the sand grain material. \nThe one\, the one caveat I would say about that though is when \nwe’re looking at the thickness of the sediment bed and the \ndifference in the thickness of the bed that includes all the \nsediment\, but all of the transport is purely just the \nsand. \nOK. \nAnd then when you say that\, all things considered\, it looks like \nthere’s some small\, some reduction in the amount of sand \nthat would have moved out of the Golden Gate\, which kind of makes \nintuitive sense. \nBut that number\, while the percentage change seems large\, \nthat number relative to be a total amount of sand moved is \npretty small. \nAm I right saying that the the the change in sediment mass \ngoing out the Golden Gate relative to the total volume of \nsand mining is relatively small? \nIs that what you’re asking? \nYeah\, yes\, I think that’s\, I think that’s correct. \nOK\, great. \nAnd then lastly\, the\, the\, the picture of the model that you \npresented with all the inputs from all the different \ntributaries into the Bay is very impressive\, but it seems to me \nit opens up it\, it’s a huge challenge to try and like \nvalidate this thing. \nI mean\, I\, is there an underlying sensitivity analysis \nthat you’ve done to try and look at\, you know\, how variations in \nflow rates in some of these different inputs change the \noverall projections of the model? \nYeah. \nSo one and one of the tricky things for this\, the sand study \nspecifically is there’s not a lot of these repeated \nbathymetric data sets to be able to model\, you know\, what \nhappened. \nThe the place we do have those are in some of the the ship \nchannels and in some of the the harbors that get deepened. \nSo with this\, with this same model\, a couple of years prior \nto this study\, we did a\, a study for the Army Corps of Engineers \nlooking at the Port of Oakland\, which I think is pretty directly \nrelevant to\, you know\, to this\, the Central Bay Area in \nparticular. \nBecause we have\, we have pre and post dredge surveys across four\, \nI think 4 different years that we looked at for that project \nwhere we would\, we would set the bathymetry to what the post \ndredge survey was. \nAnd then we would simulate like one year until they did the next \npre dredge. \nAnd we would look at the amount of sediment that was deposited \nand we could look at that\, you know\, across wet years and dry \nyears. \nSo we did do a lot of validation of deposition in in Oakland \nHarbor. \nAnd I think one thing that that you know\, probably relevant to\, \nto this is that\, you know\, in the wet years we were seeing\, \nyou know\, more than twice as much sediment deposition at \nOakland Harbor than in the dry years. \nSo what we were trying to focus on in that study was what they\, \nthey had done the deepening from like 42 to 46 to 50 feet. \nAnd then and they were trying to understand how much the \ndeepening caused the amount of sediment deposition to go up. \nBecause as you kind of\, I mean\, it’s kind of also intuitive. \nIf you dig a hole\, nature’s going to kind of want to fill it \nin. \nSo as you deepen these harbors it\, it accelerates deposition. \nBut\, but it was really hard to see that signal because it was \nswamped by the signal of\, you know\, you have a wet year\, \nthere’s twice as much sediment that comes in. \nAnd\, you know\, the estimate of the\, the deepening\, you know\, \nwas a\, you know\, 20% change in\, in\, in shoaling rates. \nAnd you said there’s twice as much sediment coming in during a \nwet year. \nThat is a sediment of not that’s not just sand\, that’s all types. \nYes\, yeah. \nAnd\, and\, and if I understand it\, the amount of sand that’s \nmoving is\, is\, is small. \nSee\, I come from the kind of contaminant background where I \ndidn’t really care very much about sand moving because the \ncontaminants are moving in the finer grain material. \nBut\, but now I’m\, I’m trying to make sure I disconnect my\, my\, \nmy sediment thinking to really be focusing on the larger grain \nmaterials. \nAnd then my last question was about you mentioned that in Bull \nat Bull’s Head Shoal\, so that there is some need for dredging \nthere. \nBut again\, the dredging\, if I’m dredging for navigation in the \nBay\, I’m not pulling up material that can be commercially \nexploited as sand. \nIs that right? \nI guess it depends on what the grain size of the material is. \nI think there is some sand that builds up on that Bull’s head \nshoulder Brenda might actually have. \nYeah. \nSo yeah\, Andy\, the sand both in Sassoon channel\, which is a \nfederal navigation channel in a different part of Sassoon and \nBull’s Head reach is 95 to 99% sand. \nAnd it’s that very similar fine grained sand that is currently \nmined out of this other part of the reach. \nSo it’s an interesting question as to whether or not mining \ncould occur on Bulls Head Reach\, which actually causes emergency \ndredging episodes on a fairly regular basis because it starts \nto encroach on the navigation channel. \nBut it it is sand\, right. \nSo I guess just so\, so\, so one question I would have\, we don’t \nneed to answer it now\, but if the Corps of Engineers is \npulling up sand\, what are\, are they’re just disposing of it And \nthen we have the companies pulling up sand and selling it. \nAnd so it would seem to me that we that they’re sort of sort of \neconomic market questions here\, but I’d like us to think about \nthose a little more. \nIt seems we should only be extracting from the Bay that \nwhich is\, you know\, needed seems to me so OK\, thanks. \nI appreciate that. \nSo Commissioner Nelson has his hand up\, but after Commissioner \nNelson\, I’d like us to go to the sand miners to present their \ncomments. \nSure\, Commissioner Nelson. \nThanks\, Pat. \nI just want to make sure I’m not over interpreting the results \nhere. \nI don’t know if you can skip back to some of the slides that \nshow changes in sand transport in the Central Bay with and \nwithout mining. \nOne of the questions that\, yeah\, one of the one of the questions \nwe’re asking ourselves is whether there’s an impact of \nsand mining there. \nThere was one that called that that that showed flux and I \nwasn’t sure I understood the difference between flux and some \nof the other slides There\, there that one\, this one. \nYeah\, yeah. \nAnd and the previous one that shows the that shows the graphic \nthat that one right. \nAnd so the I’m looking at the the the two graphics on the \nright predicted changes to sand mining\, sand transport with \nwithout sand mining. \nOne of the things we’re asking ourselves is whether it’s \npotential that Central Bay sand mining could have an impact on \nbeaches. \nI I recognize that asking that question about beaches outside \nthe Golden Gate is pretty tough given our previous presentation\, \nthe last time we had this call. \nBut but the Marina Green\, the beaches\, beaches of the highly \nused beach along the Marina green is right there next to \nnext to the sand mining area. \nAnd this this sand transport corridor\, but where this shows \nmeasurable changes in sand transport\, it’s very much in the \ndeep channel. \nAnd as I look at that\, it doesn’t give any evidence any\, \ndoes any suggestion that there would be erosion off of the the \nbeach in northern San Francisco along the Marina Green caused by \nthat sand mining. \nAm I interpreting those that this\, this graphic correctly? \nYeah. \nI think that the difference is really the\, you know\, the\, in \nboth the low outflow and the high outflow year that we’re \nseeing\, the difference is these red\, these red vectors\, which \nmeans\, you know\, transport out. \nThere’s a little bit of blue\, you know\, along the shoreline\, \nwhich is a\, a reduction of\, of land with transport. \nBut the\, you know\, the conceptual model\, I think is \nlargely the sediments coming out through the Golden Gate. \nBut then there’s also these like recirculation\, you know\, more\, \nmore shore hugging transport back in\, in\, in that image from\, \nfrom Bob Batalo. \nI can\, I can show you. \nI\, I have a couple slides that I\, I\, I have here that\, that \nshow the\, the sand flux here at the Golden Gate for\, for the \ndifferent cases. \nSo I think if you look just kind of at this bottom panel\, this is \nshowing the blue is the the amount of sand flux going out \nthrough the Golden Gate across the year in the within the the \nbaseline. \nAnd then the green is the amount of sand flux that’s going out \nacross the year in the the with sand mining. \nAnd so that’s where that that’s where that percentage comes from \nat the end of the year. \nYou have\, you know\, this is the the net transport of sand flux \nin the baseline and this is the the net transport in the in the \nwithout sand mining. \nSo that’s how you end up getting the 100 and and something \npercent there and the the high output year. \nSo I’m just going to take a moment and note for folks that \nBCD CS jurisdiction goes from Point Bonita to Point Lobos. \nIt does not stop at the Golden Gate Bridge. \nAnd just as a reminder\, we do have a bit of jurisdiction in \nthe outer area of the Bay because I know not everyone on \nthe call knows that. \nBob\, are you on the same topic? \nYes\, I just wanted to clarify something for Commissioner \nGunther and while Michael McWilliams was on the line. \nIt’s my understanding that the model results that we’re looking \nat does not include longshore sand transport. \nWe call littoral transport driven by waves along the \nintertidal shore and that’s a a known thing and we we all \nunderstood that. \nThe other point I wanted to make is that it looks like there’s \nmore than one travel path. \nThere’s the ebb and flow\, ebb and flood exchange that \ntransports sand out and in\, out on the ebb and on the flood. \nBut there’s also a wave driven transport from Ocean Beach \naround Point Lobos\, past Baker Beach\, etcetera\, around Fort \nPoint and then along Crissy Field. \nSo the model didn’t show the transport along Chrissy Field or \nthe effect that the sand mining might have on this other \ntransport path. \nThanks\, Bob. \nYeah\, thank you. \nThanks\, Pat. \nDo you want to go to Aaron? \nYes\, Aaron Holloway is here and he is going to present some \ninformation from the miners. \nErin\, are you? \nThank you\, Pat. \nYeah\, I’m ready\, available. \nI’m gonna share my screen here. \nOK. \nThank you\, Michael\, for the presentation. \nI know that was quite an undertaking to model sand \ntransport throughout the Bay. \nSorry. \nLet me losing my navigation here. \nWhat I wanted to just talk about too is kind of linking the \nfindings from the anchor model to some of what you’ve already \nheard in the in the previous presentations. \nSo some of the key findings from the model was that there wasn’t \na consistent westward transport of sand from the delta through \nthe Bay and out out through the Golden Gate. \nSo that\, you know\, sort of consistent with the disconnected \nsystem that was presented by the stratigraphy team. \nAnd so that also sort of contrasts with what the sand \nbudget study looked at\, which was assuming kind of this whole\, \nall these embayments are connected and if you have a \nsurplus of sand in one area\, it’s going to flow to the next. \nSo we want to kind of bring attention to that. \nAnd then the other important finding we thought from the \nanchor modeling was that the sediment transport from local \ntributaries was negligible and that there wasn’t much sand \ntransport\, you know\, past the head of the tide from these \nlocal tributary sources. \nAnd that was a that’s a\, you know\, substantial source of sand \nto the Bay given that there’s not much coming from the delta \nanymore. \nAnd so in the sand budget\, the local inflows were\, you know\, \nthe 0.36 million metric tons per year is what went into the sand \nbudget. \nSo we just a quick comparison of\, you know\, on the left is the \nthe disconnected conceptual model presented by the strategic \nteam where you have kind of different sources in Central Bay \nversus Sassoon Bay and that\, you know\, they’re not necessarily \nconnected in terms of supplying sand to one another. \nBut then when the when the sand budget assumed all them payments \nare connected\, you get kind of this this flow of sand from \nSassoon Bay through San Pablo Central Bay and out. \nAnd so it seems to me the anchor model is implying a more\, you \nknow\, complicated sand transport system that’s not necessarily \nconnected\, you know\, from the delta through the ocean. \nAnd so we think that’s an important conclusion to \nhighlight. \nAnd then the second one is just talking about kind of the scale \nof impacts that I think Commissioner Gunther was hinting \nat is that\, you know\, the\, the effects of sand mining in \nCentral Bay were found to decrease\, you know\, if mining \nhad not occurred. \nSo the\, the order of magnitude there was\, you know\, 30 to \n40\,000 cubic yards. \nBut again\, there’s\, it’s a very complicated system and the model \nhas limitations. \nAnd so it’s important to to discuss those. \nAnd\, and I think that Michael and Aaron did a great job in \ntheir report. \nThey have a whole section on kind of model limitations. \nThey did the sensitivity analysis. \nSo there’s a lot that goes in to such a dynamic system and \nevaluating sand transport. \nSo I know they’re\, they’re not entirely confident in the \nmagnitudes\, but we think it’s\, it’s worth\, you know\, comparing \nthat to the prior numbers that we just talked about in the last \nworking group meeting with the sand budget. \nSo in looking at the flux at the Golden Gate again\, the the net \nflux predicted in the model is just a fraction of the total \nflux. \nSo with a large amount of sand moving each way\, the the net is \na much smaller amount of that you know. \nSo if the net goes in and out of the Bay in this predicted range \nfrom the sand budget\, the model result is a a net flux out of \nthe Bay of about 80\,000 cubic yards. \nSo less than the sand budget estimate of 2000 cubic yards a \nyear out of the gate. \nSo we just thought it’d be helpful to kind of bring the \nnumbers together from the different studies. \nAnd then the last or the some of the key limitations\, I think \nI’ve already been discussed\, but but there’s lack of data on sand \ntransport in these areas that make it difficult to to validate \nthe model. \nAnd then it\, the model doesn’t include simulation of ocean \nwaves and swell propagation through the Golden Gate\, which \nis obviously a key part of the dynamics in that system. \nAnd then the other item is the\, the mine sand was represented \nwith a single grain size. \nBut in the central Bay\, you know that we’ve demonstrated that \nthe\, there’s coarse sand fractions which are mined more \nextensively in the\, in the northern lease sites. \nAnd then the southern lease site\, which is a more dynamic \nsystem is a finer grain size\, the finer sand size. \nSo that’s as expected. \nBut our concern is that if you’re going to apply a fine \ngrain size where they’re mining coarse sand\, you’re going to see \na greater impact than may actually occur. \nSo that that’s could be one of the reasons why there’s\, there’s \nthis kind of distribution of sand\, you know\, in this central \nBay Area\, which is actually quite coarse and may not\, may \nnot behave the same way that the model predicts this other\, you \nknow\, this finer sand to move. \nAnd that’s\, that’s all for the\, the discussion we had. \nWell\, thank you. \nThat’s great. \nAppreciate that. \nSo I don’t see any more questions. \nSo I hope we don’t have we’ll have them toward the end of the \nmeeting. \nSo now we can go on to our next our next presentation which is \nfrom Bruce Jaffe and he is going to be answering the questions or \nworking on answering the questions. \nWhat are the impacts of sand mining on the Bay bottom? \nAnd we really appreciate Ruth coming out of retirement to \nshare these findings with him and take away Bruce right now. \nWell\, Bruce is sharing his screen. \nIf folks could take a minute and put their name in the chat just \nso we can make sure that you are captured for the interested \nparties list\, please. \nThank you. \nI’m still making some edits to my presentation. \nSo anyway\, let let me say that it’s a pleasure to be able to \nshare the work that that we did on this study. \nThe the key people I should say are Teresa Frigoso and Amy \nFoxgrover. \nAnd I just finished my edit so I can share. \nYou take the cake\, Bruce. \nI’m usually doing it the last 10 minutes. \nWell\, on Zoom\, you can do it as it’s going. \nNo\, it’s just. \nOK. \nSo let me see if I can share screen. \nYeah\, this should be the right. \nOh\, wait\, not that one PowerPoint share. \nWe can see it. \nIt’s not in presenter mode yet. \nThere you go. \nAll right. \nOK. \nAnd I’m gonna move some people off the screen. \nAll right. \nSo Lester McKee presented to an earlier working group meeting \nand about an approach to look at the effects of sand mining using \na sentiment budget and he showed this slide and circled in red is \nwhat our group contributed to that study. \nI will point out that we are also part of the stratigraphy \nstudy\, which is interesting on how they’re\, they do have \ndifferent approaches and different conclusions. \nSo let me let me tell you how we\, we came up with a number for \nthe\, the change in storage for for sand in the system and that. \nSo it was very fortuitous that we had just finished the study \non bathymetric change in the system and that it was in in \nlarge part funded by the the settlement work group for the \nBay and what’s shown here. \nLet’s see\, do you can you see my pointer or not? \nI don’t think so. \nOK\, Upper left is 1980s survey. \nIt’s color-coded by depth. \nYou can see the channels. \nLower left does 2010 surveys. \nSo this allowed us to do a time step that we hadn’t done. \nWe’ve been looking at historical changes from the 18\, mid 1800s \nto the 18 to the 1980s. \nAnd what’s shown is that the the areas where there’s erosion of \nthe bed and a potential source of sand to the system are in in \nblue colors. \nAnd the areas where there is deposition to the bed or gain in \nthe bed were areas where sand might be sequestered. \nSo pretty simple outline talk about the methods\, the results \nuncertainty analysis cause uncertainty’s key to to to \ndetermining whether you can trust what what the study \nresults are in a summary. \nAnd if time allows\, I could talk a bit of that said trails\, \nalthough Mike McWilliams talked a little bit about it on how \nit’s looking at the connections between different parts of the \nBay in terms of the sand transport. \nAnd that was a pilot study funded by USGS. \nOK\, So the methods gravity cores were taken\, this is not San \nFrancisco Bay in the picture. \nObviously there’s ice and we we’re not on such a big ship\, \nbut it shows the gravity core well where it’s just\, it’s like \na dart that has hundreds of pounds of weight on it that just \nfree falls and goes into the sediment. \nAnd these cores were taken between 1990 and 2016. \nAnd in total there were 186 cores. \nAnd the length of these cores varied from about 50 to 360 \ncentimeters. \nSo we’re looking at it collects sediment\, depending on what the \ndepositional and erosional history is\, that could be recent \nif it’s in a depositional area with some older scent beneath it \nor sediment that’s hundreds or even hundreds of years or even \nolder than that. \nAnd on the right you can see the distribution of the the the \ncores and you can also see in yellow where the mining areas. \nOK\, So with the as geologists\, what we do when we get the \ncores\, as we split them open\, we take a look at them and we log \nthem. \nAnd these are just a couple paper logs. \nThe symbol for sand are dots. \nSo you in in this with this\, the core log on the right\, you can \nsee lines of dots and we then took the information from these \ncores and that’s a paper log. \nThis is now interpreted. \nThese are published in open file reports and you can see the \nsymbols and again there is some sand in in this core in the blue \non the left. \nSo we take all this information and I won’t bore you with the \ntrying to describe this\, this slide. \nBut basically what we needed to do to be able to determine \nwhether the the bed of the Bay was a source or a sink of sand \nis we needed to to look in the the sediments to see whether or \nnot\, you know\, see where the sand was located. \nAnd we did this at 10 centimeter intervals and it involved \ncorrecting for the fact that when the core is collected so \nthat we we had a\, a common vertical datum and we shifted \nthem. \nAnd then this is all on the report the details. \nBut what what became apparent very\, very quickly was that the \ncores alone just didn’t have the coverage that we needed. \nSo we then augmented the the core data with surface samples \nand we evaluated what what the error introducer\, the \nuncertainty introduced by doing that. \nAnd surprisingly it wasn’t as large as we anticipated. \nIt’s about a 10% uncertainty by augmented\, but that allowed \nanother 700 locations where we could then create a 3D map of \nthe sand content or 3D model of the sand content of the \nsubsurface sediments. \nSo we had done something similar to this in Alviso Slough where \nwe use cores and instead of trying to estimate the sand \ndistribution in the in the subsurface settlement we we \nused\, we were looking at Mercury remobilization. \nThis was work with Amy Foxgrover published in 2019 and there’s \nMark Marvin Day bus quality was was lead on the Mercury part of \nthat. \nHe’s from the USGS as well. \nSo we did this approach where we created this\, the 3D model for\, \nfor the subsurface sand content and we did it in the embayment \nscale and it was a significant amount of work. \nAgain\, Teresa Fragoso and Amy Fox Grover did a fantastic job. \nEach of these sub embankment models had about 3010cm layers. \nAnd this is just an example of one layer\, 110cm layer. \nAnd it’s\, it’s actually an amalgamation of\, of different \nsub embankments and you\, you can see this is from zero to 10 \ncentimeters. \nAnd you can see the\, how heterogeneous the Bay is in \nterms of sand. \nThe more yellow\, the colors\, the higher the sand content. \nSo interesting pictures\, but that we have we have to analyze \nit then to get our answer whether the Bay is a source or a \nsink of sediment of sand. \nSorry\, I want to point out that Sassoon Bay because there were \nnot the themitry surveys there in all of 2010 and San Pablo Bay \nin the shallows. \nWe’re not when\, when I talk about the the Bay\, I’m talking \nabout the\, our study here\, which includes most of the Bay\, but \nnot the entire part of the Bay. \nAnd then I\, when we for initial analysis\, we excluded mining \nareas shown in yellow here\, dredging footprints and orange \nand disposal sites in a in a kind of a pinkish color. \nWe did go back later on and account for those separately in \na later phase of our analysis. \nSo the results different sub embayments were either a source \nor a sink of sediment of sand. \nSorry\, the blue shows the sub embayments that were a source. \nThese were places where there was sand in the\, in the bed that \nwas eroded. \nAnd so more sand is available then for other parts of the Bay \nor to go out the Golden Gate\, the red and it’s primarily \ncentral Bay is a place where there was deposition of sand so \nthat the bed was a sink. \nAnd Michael McWilliams talked about his his time scale of a \nyear limited by computational times. \nSo we normalize to a\, to a rate per year. \nAnd this is the normalized rates and the in total it was about \n1/4 of a million cubic meters of sand that was supplied by \nerosion of the bed per year. \nAnd this is for all the areas excluding where the human \nactivities were. \nSo might not be a surprise to anyone that the human activities \nwere significant. \nSo here’s a comparison of the rates of change and sand volume \nand the bed for the the two mining areas\, Central Bay and \nSassoon Bay. \nThese are the lease areas and Central Bay alone is quarter \nmillion cubic meters per year so soon as about a tenth of the \n1\,000\,000 cubic meter per year and all the other areas we’re \nabout a quarter million cubic meters per year. \nNow this is lost from the bed. \nObviously the mining material what’s been mine is a different \nbeast than the areas outside the human activities where it’s it’s \nnot gonna be available for other either to go out to Golden Gate \nor other parts of the Bay. \nAnd these are just from bathymetric change. \nSo the this does not account for the amount of my materials that \nwas reported in as mined. \nIt’s just from for that 1980s to 2000 tens. \nThere was a lowering of the bed in in these these two mining \nareas. \nSo uncertainty analysis\, I could go into this salon for quite a \nwhile\, but I won’t it’s in the report. \nSo the three sources of uncertainty that we addressing \nthe report was uncertainty from interpretation of the core logs\, \nuncertainty from augmenting core data with surface at sent and \nsamples and then uncertainty associated with bathymetric \nchange analysis. \nSo the first two uncertainties are easy to quantify. \nThe third is not the uncertainty interpretation core log. \nIt did change the magnitudes of the of the sand volume in the \nbed\, the rate of change the sand volume in the bed\, but it was it \non\, you know\, 20% change from going from conservative minimum \nsand content to our best estimate or from a maximum sand \ncontent to our best estimate. \nAugmenting with surface sentiment samples which assume \nthat it was a representative of the of the sentiment below did \nnot have a large effect. \nIt was about a 10% and like the interpretation of the core data \nof the core logs it it didn’t have an effect on the direction \nthat is the the bed in the areas away from human activities was \nstill a source of of sand. \nThe uncertain in the bathymetric change is potentially \nsignificant and so it depends on the degree of randomness and \nsurvey errors. \nSo if the survey errors are random\, they cancel out and the \nuncertainty is and mathematic change is low. \nSo\, and if the survey areas are systematic\, the uncertainty in \nbathymetric change could is is large for a large area? \nFor the small areas like sand mining leases which the \nuncertainty from bathymetric change is low. \nAnd So what we presented in the report was what the these \nuncertainties translated to. \nAnd then it’s really depending on what your use for the data is \nyou can\, you can and how random you think the survey errors are\, \nyou can assign a a value to it. \nSo in summary\, the question whether bed sediments in San \nFrancisco Bay are sources sand is answered. \nSo that’s this is the change in the storage. \nSo bed sediments are a source of sand\, not too surprising because \na lot of the Bay is eroding and so if sand is in the sediments\, \nit’ll be a source. \nBut it\, it\, it hadn’t been shown till this this study. \nAnd then how certain are we of this answer the interpretation \nof sand content in the core logs or from augmenting the data with \nsurface sediment sample data doesn’t affect our our \ncertainty. \nAnd the answer the the uncertainty of bathymetric \nchange could be potentially significant. \nSo additional studies could be made done on on how random this \nthis error is. \nFrom my experience\, random that the errors are random\, but I I \ncan’t rule out that there are systematic errors. \nBut the systematic errors would have to be systematic over many \ndifferent separate surveying events. \nSo in my way of thinking the likelihood of that is not as \ngreat. \nAnd then how does sand volume changes in mine years compared \nto areas without human activities? \nI’m just reiterating the result that that the sand volume change \nin the bed in the mining areas and this is from bed lowering as \na net I said is either greater than or similar to the sand \nvolume changing areas in the areas without human activities \nin the Bay. \nSo as I said before\, there’s publication Center\, publications \ngroup and there’s also two USGS data releases of the data used \nin the analysis. \nSo with that questions and discussion. \nThank you\, Bruce. \nSo first\, we’ll go to. \nI have a couple questions\, but first we’ll go to the other \ncommissioners. \nAndy or Barry\, do you have some questions here? \nNo\, no\, nor do I. \nOK. \nWell\, yeah\, I just wanted to reiterate Bruce that. \nSo basically as I understand your summary and thank you for \nbeing so clear about this that you know\, going to the question\, \nI think that’s always really helpful. \nSo basically you’re saying that that from the bathymetric \ninvestigation\, the change in the sand mining areas and the change \nin the other areas isn’t really statistically different. \nIs that what you’re saying? \nI wouldn’t be as as direct on statistically different\, but I \nwould say that there’s same order of magnitude\, same order. \nI said that’s what you said. \nYou’re right\, statistically. \nSo it’s just and I\, I would\, I’d say that this is not a a after \nall this work\, I would say it’s not a\, an earth shaking result. \nIt\, it fills in\, you know\, missing data and you know\, it \nallows a sediment budget to be calculated. \nBut to me that the results from the stratigraphy team\, those I \nthink are\, are more profound\, especially the results that the\, \nthe material being mined is\, is old order\, 1000 years old. \nAnd I’m glad that the\, you know\, that the study was able to \naccommodate them\, that the way they they were able to to date \nthe material. \nAnd the sand miners were incredibly helpful in\, in\, in \nallowing a collection of material on a moonless night \nwith no lights\, red lights\, so that they didn’t reset the the \nquartz screens for optically stimulated luminescent dating. \nSo I think that I think that’s a a very key\, key result. \nOK\, thank you. \nYeah\, I\, I think you’re right. \nSometimes confirming what everyone has theorized over many \nyears with real data. \nIt it it’s just very\, very important. \nAnd and that’s seems to be what this study that you’ve done has \ndone. \nWe people have talked about this for a long time\, but you’ve \nactually collected data to show that indeed the standard \nhypothesis is\, is is correct. \nSo that’s\, that’s a big\, at least from my point of view that \nthat’s a big contribution. \nOK. \nAnd that’s a perfect segue. \nYour comment about the sand miners being productive\, very \nproductive members of this investigation team is is really \nright on. \nSo we will go to Aaron Holloway. \nWould you is there anything you’d like to share with us \nright now\, Aaron? \nYeah\, sure I do. \nI have a question for Bruce. \nBut before I get there\, I wanted to bring up a topic that was\, \nyou know\, at I think Commissioner Gunther and Nelson \nasked it in the prior topic about sand transport and the \ncity of Golden Gate and in Bay beaches. \nAnd I just wanted to note that the\, the beaches that were in \nquestion\, I think Crissy Field Marina Green\, those have have \nbeen experiencing accretion. \nAnd so there’s a\, there’s a clearly a supply of sand \narriving at those beaches. \nAnd I don’t think that transport pathway was\, was resolved in the \nmodel\, but I think I think that was a point Bob was making as \nwell. \nBut just wanted to clarify that. \nMy question for Bruce is the in looking at the results in your \nreport and then the results from the stratigraphy team\, the one \nthing I noticed was that the strategic free team said that \nSan Pablo Bay was they had a hard time finding any sand when \nthey were looking at the cores throughout San Pablo Bay. \nBut I noticed in your study there’s quite a bit of sand\, you \nknow\, in the cores or the surface sample. \nSo I’m just wondering\, I assumed you were kind of looking at the \nsame cores\, but maybe not. \nDo you have any thoughts on why that kind of those different \nconclusions could be reached? \nWe were looking at the same cores. \nThe stratigraphy team’s ability to look at multiple cores was \nlimited\, as it’s the case in all scientific investigations\, but \nespecially in their case. \nSo\, yeah\, the\, the cores that we\, we were able to\, you know\, \nthese are course from 1990\, the course we were able to\, to\, to\, \nyou know\, look at did not have a lot of sand in them. \nSo it’s not\, it’s not that the result is not that the \nconclusions are different. \nIt’s just a matter of limitations of the study. \nIf\, if there was\, you know\, if there was a\, a desire to \ncontinue the studies\, the\, you know\, a better effort could be \nmade to\, to find those\, those cores with the sand. \nAnd I think one of the limitations of the study was as \nthey were doing it during COVID\, so they had very limited ability \nto be at USGS. \nSo I\, I know that COVID is starting to sort of feel like \nit’s in the rearview mirror a bit\, but it\, these studies were \nall ongoing during COVID. \nSo there was some challenges associated with the pandemic as \nwell as time limitations. \nThat’s entirely true. \nThis we had a it was even more limited because we were working \nat the USGS core facility and difficult to get access. \nSo during COVID. \nWell\, another thing I’d just like to thank you for is kind of \ntalking a little bit about the connection between the work you \ndid at Alvesa Slough related to deposition there. \nThat was that’s that\, you know\, that was really so revealing and \nhow we do the marsh restoration and it’s a it’s a really\, really \nlearned a lot from that. \nAnd you know\, we don’t often getting to do basic science \nassociated with these problems is is really important and \nyou’ve been part of that for a long time. \nBut so I just wanted to put a shout out again for the LV so \nslow work. \nIf we if we hadn’t done that LV so slow work\, we would have \nnever undertaken this work ’cause we developed techniques \nthere and and applied them here. \nOh\, well\, that makes me feel good because we did wrangle \nquite a while for that contract\, didn’t we? \nYes\, it was not a it was not an easy process administratively. \nOK\, well\, I think this\, this is my understanding is now we need \nto have questions from anyone who is interested. \nSo I would look forward to people\, participants raising \ntheir hands with questions. \nPlease use the raised hand. \nAnd I think if there’s no questions\, I’m kind of scrolling \nthrough myself. \nI don’t know\, Bruce\, if you wanted to share the said trail \nslides since we don’t have questions and we have half an \nhour unless people have questions\, of course. \nI\, I\, I get that\, that this type of study is different than \nwhat’s normally done. \nAnd perhaps if there’s questions that come up when\, when either \nlooking back over the presentation or the report\, feel \nfree to to contact me or Teresa Frigosa or Amy Fox River. \nSo let’s see. \nSo I just have a few slides on said tools\, said trails. \nSorry. \nSo this was a very late thought of of\, of something that could \nbe helpful for understanding sand mining and and its effects. \nSo had the leeway to do a pilot project it it this is so this is \na tool set trails. \nIt’s a tool developed by Deltares. \nThere’s a group there\, Mick van der Wagen\, floor rolls ink are \nare the two of the people who worked on this. \nAnd the\, the\, I think Pearson is the is the\, the set tool set \ntrails developer. \nSo it visualizes sediment transport pathways and \nconnections. \nAnd so it starts with a a model with model output\, which is \nhydrodynamic output and the models that Deltares uses Dell \n3D four and D4 little FM. \nAnd then that’s in Eulerian that that means the output is its \nfirst sells for fixed points. \nAnd then it uses formulations to get Eulerian sediment transport \nfields. \nAnd then it takes that data. \nAnd then instead of looking at the those\, those vectors in A at \na fixed point\, you go into the Lagrangian framework where it \nfollows points or follows particles and sees where they\, \nthey end up in a system like San Francisco Bay. \nIt’s\, it’s not intuitive because it’s\, it’s tidal. \nSo depending on when the particles started\, when the sand \ngrain here starts moving\, it could either go into the Bay or \nout of the Bay. \nAnd as well\, if there’s a flood event\, that’ll definitely have \nan effect. \nAnd then the part that and is was developed that I was \nparticularly interested in\, I mean the\, the\, the visual \nvisualizations of of sediment or sand pathways is I think it’s \nvery interesting. \nMichael McWilliams showed some of those from from his model\, \nbut they they’ve the people at Deltares have developed an \nassessment of sediment connectivity. \nSo I’m just gonna show one place in Central Bay where they did \nthis as part of the pilot study. \nThere is a memo on this and I can contact Mick Vanderwagen and \nand team about sharing that memo. \nI have no problem with sharing it. \nI think it’s a great tool and can be used in many different \napplications where modeling of particles is is is one of the \nparts of the study. \nSo here we go. \nSo this is for lease area 779 W and on the left are the \ntrajectories. \nSo these are of particles that are moving through the lease \narea. \nSo you can see that they come from different places and there \nare places where within the lease area where there’s more \nparticles moving through and places where they’re\, you know\, \nless\, less particles. \nAnd this was done for sand. \nSo I should say more sand or less sand on the right. \nI think it’s\, it’s another\, another application where the \nsand particles that were within the lease area where they go and \nyou can see it’s a different pattern\, but this tool and \nconnectivity\, it’s the same. \nThis is the\, I do believe it’s the same area\, mining area 1. \nAnd so for the\, the red circles is where the sand is coming from \nthat goes into that mining area. \nAnd the larger the\, the\, the larger the dot\, the larger the \ncircle\, the greater the strength of connectivity. \nAnd then on the right is let’s see. \nOh\, I see these are different title cycles\, 55 on the left and \n50 on the right. \nSo you can see there’s more connections. \nThe part the sand’s coming\, the red is it’s coming from farther \naway\, it’s entering the area and then the yellow dots are where \nthe sand leaving the area and and the connections are \nstrongest nearby and to the north\, which is interesting. \nThere’s not connections to the South as that are strong and the \nopen coast as well. \nSo just wanted to share that that this was this was a pilot \nproject. \nIt didn’t do the entire Bay and it wasn’t as sophisticated the \nmodels that can be applied. \nSo there’s limitations\, but it illustrates the concept. \nSo thanks\, Bruce. \nAnd if you do want to share that memo\, I think it would be great. \nWe could pop it up on the website for people to peruse. \nThe other thing I just want to note for the group is that in \nthe the Sand study reports are all in Appendix G of the Overall \nFindings document. \nOn our website\, however\, Bruce’s report is not in there. \nSo if you’re going to go look for it\, it’s not there. \nAnd that’s because USGS has not released it yet as final\, final \npeer reviewed. \nBut as soon as it gets released\, which I understand from Bruce is \ncoming very soon\, we will post it to the website. \nSure. \nOK. \nOK. \nSo thank you very much. \nBruce\, are there any questions from commissioners on Bruce’s \nlast few slides? \nOK. \nI don’t see any and any comment from Aaron\, the minor \nrepresenting the minors. \nNo\, no\, nothing else. \nPat\, thank you. \nOK. \nThank you very much. \nWell\, well\, Brenda\, we do have a few more minutes. \nAnd so I always like if there’s time to understand what the next \nsteps are. \nI know you went through that at the beginning\, but perhaps you \ncould refresh our memories. \nSo what’s happening next? \nSure. \nSo we’re taking a little break between this meeting and the \nnext. \nSo the next one is November 22nd\, which I believe is the \nweek before Thanksgiving. \nSo you all should still be in town\, hopefully\, fingers \ncrossed. \nAnd I believe at this point we’ve completed the suite of \nstudies\, the overview presentations of the studies. \nAnd so I haven’t developed the agenda for the next meeting. \nPat\, you and I will probably sit down and chat some more\, of \ncourse\, with Greg and talk about what we’d like to cover. \nThere’s a few options we can pull up in the policies. \nWe can pull some literature for biology pieces and or we can \nalso talk about some of the questions that the Commission \nhad at the Commission meeting\, which were more related to \neconomics and uses of sand. \nSo it’s to be determined what the next agenda item is. \nOur next agenda is for the next meeting. \nWe’ll probably do a little bit of pulling together of these \nstudies as well\, but we’ve got some time this time to pull \nthrough that. \nWell\, that’s excellent. \nAnd then after that\, we will be getting together information for \nthe policy question\, right? \nYeah. \nOK. \nSo briefly\, what’s the policy\, what’s going to come before the \nCommission? \nYes\, OK. \nWant to go over what that is real quickly\, What the policy \nquestion is. \nWell\, I don’t know that we’ll be asking the policy question of \nwhether or not to permit mining\, mining\, ’cause this is not that \nforum\, right? \nSo this forum has really been about providing the science to \nthe commissioners so that they can help support the other \ncommissioners. \nAnd understanding that\, I guess that’s what I was getting at\, is \nwhere that’s what really this is about. \nThis is about supplying the science so that we can make a \nmuch better informed decision. \nYeah. \nAnd that’s\, yeah\, if we do talk about policy\, we would just go \nover what policies apply to this world\, but we would not try to \nreach any conclusions or discuss the proposed project because we \ndon’t actually have the proposed project at this time for the \nnext. \nWell\, the other\, the other reason I bring that up is \nbecause the policies that BCDC has\, although some of them\, \nthey’ve been many of them have been around for many years. \nThey\, there’s a lot of them and so often so\, so understanding \nthe policy contact context of different issues is\, you know\, \nis\, is\, is not a a small task. \nSo that\, you know\, that will be kind of this scientific data \nwill be useful for us to do that. \nAnd I really appreciate everybody’s involvement in \ngetting this information. \nThis has been a huge effort and we we’ve gotten some very \nvaluable responses. \nOK\, so last call for then\, then I guess we\, we always have to \nhave in in these public meetings a public comment forum. \nSo formally\, I would like anyone who would like to make a public \ncomment who’s here on something. \nThese are typically things that are not on the agenda. \nBut if you’d like to make a public comment to this group\, we \nwould be glad to hear it. \nAre there any hands raised? \nI have Jen\, see you and I also have Andy\, Commissioner Gunther. \nSo maybe we go to Jen first\, then Commissioner Gunther next. \nGreat. \nThank you\, Brenda. \nThank you\, Commissioner. \nThese are amazing. \nThis is an amazing forum to learn more about science and I \nreally appreciate all the work. \nOf course\, I guess my question or my comment rather\, is I’d \nlove to see\, I’d love to know more about how the science is \napplicable to our outer coast areas. \nWe\, you know\, we did hear some and mention of Ocean Beach and \nthe main ship channel and\, and that there was a figure that was \nshown looking at transport. \nIt really there’s a lot of resiliency work that of course \nis happening and has been for a long time. \nI would really love to either get a list of the studies that \nhave been done that that\, you know\, would be helpful to figure \nout what’s happening on the coast or understand from these \nvery big brains what additional science is needed to to \nunderstand our our ocean transport\, you know\, the coastal \nsediment transport issues and littoral zone issues. \nI’ll stop at that. \nThank you. \nThank you. \nOK\, Andy. \nYeah. \nThanks\, Pat. \nSo two things I want to just congratulate the staff and the \nscience committee. \nThis is\, this is the right way for us to do things. \nI want to thank the\, the\, the industry developing this kind of \ninformation over the time we’ve had is gonna make our next \ndecision about permitting just so much more intelligent and\, \nand it it’s really important that we do this kind of thing. \nI really happy to see this. \nThis has been an approach that the Regional Water board has \nused with its permittees for years and years and it’s been \nreally\, really valuable for focusing our discussions. \nThat being said\, this is a lot to get our heads around and it’s \na very\, it’s very complex and the uncertainties are are \ndifficult to understand and and yet could have a profound \ninfluence on how we frame the the our findings to the full \nCommission. \nAnd so I would really look forward over the next couple of \nmeetings for those of us\, those who are the the experts to \nreally help pull together kind of where\, where the agreement \nis\, where we need to know more and how we might learn that it. \nIt wouldn’t surprise me to see a structure of a permit where \nthere’s\, you know\, there’s ongoing monitoring and invest \njoint investigation\, this sort of joint fact finding. \nI received a letter sent to Brenda by Jim McGrath\, who has \nstudied these issues for years. \nThat was really helpful to me. \nSo as we pull this stuff together\, I\, I think we need to \nbe\, we need to accept that there’s gonna be\, to really make \nthe most of it. \nWe’re going to\, we’re going to need to synthesize it in a way \nthat really gives a\, gives the full Commission an understanding \nof where we really think we’ve figured things out and where we \nthink there’s other questions. \nAnd\, and it’s incredibly valuable to have Bob and Bruce \nand others contributing in this way. \nAnd that’s going to be is hugely beneficial as well. \nSo\, so there’s just a lot here. \nAnd\, and I and I hope that we’ll be able to\, to organize it in a \nway that can really educate the full Commission when it comes to \nthat. \nAnd of course\, Brenda\, that’s your job. \nHey\, very well said\, Andy. \nWell\, I think that brings us to adjournment. \nOne last call for questions. \nOK\, seeing none. \nThank you everyone for your participation. \nI’ve been really impressed with how everyone involved in this \nhas stuck to it that I mean\, we still have pretty much the same \nnumber of people we did at the first meeting. \nAnd that tells me that the presentations have been \nfascinating and also that the material that is being shared is \ninformation that people are very anxious to get a hold of and and \nreally appreciate learning about. \nSo thanks. \nAnd with that\, the meeting is adjourned. \nWe will re adjourn on November 22nd. URL:https://www.bcdc.ca.gov/event/september-4-2024-sand-studies-commissioner-working-group/ CATEGORIES:Sand Studies Commissioner Working Group END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/Los_Angeles:20240821T100000 DTEND;TZID=America/Los_Angeles:20240821T120000 DTSTAMP:20260624T062646 CREATED:20240716T205049Z LAST-MODIFIED:20240910T182134Z UID:10000186-1724234400-1724241600@www.bcdc.ca.gov SUMMARY:August 21\, 2024 Sand Studies Commissioner Working Group DESCRIPTION:Meeting agenda \nPresentations \n\nSan Francisco Bay Sand Transport Study Ring Analysis\nSan Francisco Bay Sand Budget\n\n \n \n \n \n \n meeting recording & transcript\n \n \n\nTranscript\n\nPerfect. \nThere we go. \nAll right\, here’s some. \nSee some more people. \nYesterday I was riding my back bike out to the Bay and I \nnoticed that there were all these trucks going back and \nforth on the road on sort of on the other side of a of a little \nslew and I realized it was trucking coming back and forth \nto deliver dirt to pond A to West where we are restoring a \nmarsh. \nYou know\, we’re\, there’s a pond there and we’re filling it in \nfor a marsh. \nSo that was very exciting to see. \nWe\, you know\, we’re working with dirt brokers to get the money \nfor\, I mean\, to get the dirt for free. \nAnd so it’s very much dependent on the construction cycle. \nBut the staff who were working on this project are making the \nmagic work. \nIt’s really exciting. \nAnyway\, I thought this group might care about that. \nYeah\, we are definitely caring about that and working on making \nit happen. \nYeah\, that’s our other commissioner working group. \nSo looks like we have Andy. \nPeople are still feeling filling in\, so I think I’m gonna. \nI’m wondering if I should unplug myself from the system or not. \nYou always wonder\, right When you have multiple screens going\, \nshould you be on three\, two or one? \nSo do we see Pat yet? \nYeah. \nI should be here. \nI’m sorry. \nI meant Barry. \nYou are here. \nOK? \nYeah. \nBrenda’s clearly losing her mind trying to keep it all together. \nOh\, there’s Barry. \nHe’s right in the middle of my screen. \nSo I think we have all the commissioners. \nWe have Bill Butler\, we have Aaron Holloway\, we have \nChristian Marsh. \nAnd I don’t see Erica yet. \nI’m here\, Brenda. \nOK\, good. \nThank you\, Erica. \nSo I think. \nOh\, and Mike\, so we have the sand miners and so we have the \ncommissioners\, we have the sand miners\, we have the independent \nscience panel members. \nI’ve got Elias\, one of our presenters I’m looking for. \nSorry\, there’s a million of you on the screen. \nThank you all for joining. \nI am looking for Lester and of course\, he’s in New Zealand. \nSo always a little bit of a lag and I think it’s early in the \nmorning for him still\, so we’ll give it another minute. \nAnybody got any good jokes? \nI think you just joined. \nThere’s Lester. \nOK. \nI think we have all of the people. \nAll of you are very important\, but we have all the people we \nneed to make this rock’n’roll. \nSo Pat\, I will turn it over to you. \nWell\, first\, I want to welcome everyone for taking part in this \nprocess. \nIt’s\, it’s very important that we do this as just one of the \ncomponents that we need to do to make the the region of San \nFrancisco Bay more resilient to climate change\, which I know we \nwere all very committed to. \nAnd we’re of course\, concentrating on being able to \nbuild sea level rise\, sea level rise protections\, and also just \nthe\, the\, the\, the functioning of the Bay as an economic and an \necological engine in our community. \nSo with that\, I’m going to start off with an informal roll call \nof the commissioners and\, and the staff. \nSo Catherine\, could you help us with that? \nYes\, Commissioner Nelson\, I’m here. \nCommissioner Gunther\, Chair Showalter here. \nAnd then BCDC staff who will be supporting this are Brenda \nGaiden here and Greg Scharf here. \nWe have everyone. \nThanks. \nOK\, thank you. \nAnd Brenda\, you’re going to go over some ground rules. \nYeah\, I’m going to just quickly remind folks that we’re all here \nin a collaborative effort to best understand the science of \nsand and sand transport in the Bay\, understanding that sand \nmining is an actor in this realm. \nWhen? \nSo we’re gonna have basically presentations\, We’ll have a \nmoment or a period for the sand miners who are the principals on \nthis issue to provide comments and then we’ll open the \ndiscussion for commissioner questions first. \nBut the audience is absolutely or the participants\, not \naudience participants of the commissioner working group are \nwelcome to raise their hand and join in. \nYou will call on folks in order. \nWe’re going to try to stick to a schedule\, but we have\, I think \nample time for discussion today hopefully. \nAnd if you want to put questions in the chat\, we’ll also try to \nmind the chat and have that as a place where people can put \nquestions if they are thinking of something and don’t want to \nforget before the time comes to chat. \nThere is a public comment period\, the last part of the \nmeeting. \nSo if you want to make a public statement\, that is the time to\, \nyou know\, make like a comment that’s overall versus discussion \nabout the studies. \nI do want to note that the independent science panel \nmembers\, our esteem group who have been overseeing these \nstudies for now\, gosh\, it’s been four or five years. \nBob Battaglio\, Dave Schulhammer and Craig Jones\, I believe are \nhere with us today. \nAnd then we also have Lester McKee who’s going to present \nfrom SFEI and Edwin Elias from Del Terrace. \nI’m gonna note that we these are both folks from the \ninternational community. \nDel Terrace is in Netherlands and Lester’s home base is New \nZealand. \nSo appreciate them spending weird times of the day. \nIt’s tomorrow for some of them with us. \nI know it’s not necessarily the best time of day for you all\, \nbut we appreciate you being here. \nAre there any questions on that? \nNo. \nOK\, I’m going to quickly\, quickly just do framing for the \ngroup and I will. \nYou’ll probably all disappear\, so hang tight. \nLet me get my screen up and running. \nOK\, Can you all see this? \nSomeone has to say yes ’cause I can’t see you anymore. \nCannot see it. \nOK\, I’m gonna try to escape back out. \nTry again. \nA new dub. \nTriple screens was a bad idea. \nOK\, how about now? \nCan you see that? \nOh\, here we go. \nSure. \nI have to hit the button twice. \nOf course we have to hit the button twice. \nNow we can see it. \nBrenda. \nOK\, excellent. \nThank you. \nThanks for pausing for my technical difficulties. \nOK\, so this is the BCDC stand Studies Commissioner working \ngroup. \nWe’re focused here on the science that we have learned \nover the last several years and I’m just going to give a high \nlevel overview for those who may be joining for the first time. \nSo the process that we’ve been engaged in for the last several \nyears is BCDC along with the water Board\, the EPA. \nNo\, not the EPA. \nThey don’t issue a permit. \nState Lands Commission leasing and the Army Corps of Engineers \npermitted sand mining in 2015 as part of BCD CS requirements. \nWe required that the arm that the sand miners provide $1.2 \nmillion towards the study of sand transport and issues around \nwhat it means to take sand out the sand system of the Bay. \nWe formed a technical advisory committee\, which had a host of \nthe agencies that are involved\, both regulatory and resource \nagencies\, as well as a few of the interested parties\, \nincluding the Coastal Commission because they’re interested in \nthe Outer Coast and Baykeeper. \nThe technical advisory committee formed management questions. \nThey helped develop study scopes\, they developed and \nrequests for proposals\, and they reviewed proposals as part of \ntheir process. \nWe selected and we’re honored to have an independent science \npanel of some very esteemed folks who’ve been working on \nsediment for most of their career of many decades. \nAnd so that includes\, as I mentioned\, Bob Battaglio\, Dave \nSchulhammer\, Craig Jones\, Paul Work\, and also John Legere\, two \nof which are not here with us today due to other commitments. \nBut their job was to help us review the proposals. \nThey helped revise some of the scopes. \nThey helped us identify the science teams\, identify and \nselect the science teams. \nThey worked with the science teams over a period of a couple \nof years\, two years to complete the studies and keep things \naligned. \nThere are multiple quarterly meetings and check insurance. \nAnd then they developed a findings report that summarizes \nthe work of across the studies. \nWe are now in the commissioner working group phase. \nSo we are here to discuss the study findings. \nWe had a first meeting in July on July. \nWe have this one one coming up on in September and then \nNovember. \nAnd our process is leading to the next stages\, which sequent \nNEPA is ongoing with state lands right now. \nI don’t know what’s happening with NEPA at the moment\, but \nwe’ll be looking at permitting in 2025. \nSo these were the study questions that were asked. \nThere are multiple tiered questions below\, but to not \noverwhelm everybody with questions on a slide\, the first \nmain question was\, is mining at existing lease areas at \npermitted levels having a measurable or demonstratable \nimpact on sediment transport and supply within San Francisco Bay? \nThere was questions about sustainability of this activity. \nWhat were the anticipated physical effects of sand mining \nat permitted levels on sand transport and supply within the \nBay and the outer coast? \nWhat’s that connection? \nAnd then the impacts to active sand and what’s feeding it\, \nwhether or not the sand was old or if it’s new sand. \nWe heard a little bit about that last time. \nAnd are there feasible alternatives or approaches to \nmining sand in San Francisco Bay? \nThe studies admittedly could not address all of these questions. \nWe had limited funds and limited time. \nThe independent science panel was able to kind of sift through \nthe studies to help us identify what we could answer with the \ninformation that we thought we could get through the studies \nand help direct the studies to focus them. \nSo these were the questions we started with. \nWe did not answer all the questions. \nWe’re perfectly clear and honest\, transparent about that. \nWe did what we could with the time and money that we had and \nwith the ability for us to understand this very large\, very \ncomplex system that is San Francisco Bay. \nJust a quick\, quick\, quick overview. \nSo the lease areas here is the Central San Francisco Bay lease \nareas. \nThe primary sand type is coarser grain material\, which is the \nleft pile in the slide. \nThere is some sand along Crissy Field\, the Presidio Shoal\, which \nis that finer grain sand that you see in the right part of the \nthe right pile in the slide. \nSassoon Channel lease area. \nThis is the lease area that we have up in the most eastern \nextent of the Bay and the sand is fine sand. \nOops. \nAnd then the last lease area that we have is middle ground \nShoal. \nIt is also fine grained sand\, just as a reminder of where the \nareas are that we’re talking about. \nThe equipment is hydraulic\, so hydraulic mining\, two different \ndrag head. \nWell\, one’s a drag head on the left\, which is the Martin \nMarionetta set up with a fish screen. \nThat silver tube that you see in both slides\, both pictures is \nthe fish screen to exclude fish and then lens suction pipe which \nis on the right. \nAnd just as a reminder of the framing of the mining \nactivities\, it is for construction aggregate. \nIt is not navigation dredging. \nAnd because this is mine specifically for the aggregate \nindustry\, it’s not really considered a beneficial reuse In \nthe LTMS lexicon. \nMining occurs year round. \nThere’s no work windows on mining. \nThere is a reduced period of time in which mining occurs in \nthe early\, I guess it would be late winter to to reduce impacts \nto our smelt lining. \nMining locations are based on the leases and the grain size. \nSo when the miners get an order for a particular type of sand \nthey reach\, they go to that area of their lease to retrieve that \ntype of sand and mining happens often in the same area. \nAnd you’ll see that in some of the meeting\, in some of the \npresentations that Edwin is going to provide today. \nAnd why am I not moving? \nOK\, there we go. \nLast. \nI think this is my last slide. \nWe’ll get you in just a second\, Jim. \nSo the questions that we looked at last meeting\, well what we \ndid at last meeting was we had the independent science panel \nmembers Dave Schulhamer and Bob Battaglio gave an overview of \nthe findings report\, which is on BCD CS website under the Sand \nMining Commissioner Working Group and the UT Austin folks. \nZach Sickman presented the provenance and aging work that \nthey did and that study is in Appendix G along with all the \nother studies. \nAnd then lastly\, the questions for today are listed in the \nagenda. \nBut how does relic sand is? \nHow does how does mining affect relic sand or sand in transport? \nAnd how much sand is there in the Bay? \nAnd how does mining affect the budget? \nAgain\, we cannot completely answer these questions\, but \nthese studies presented today by Edwin and Lester will look at \nvolumetric change analysis and what that tells us about sand in \ntransport or sand in place. \nAnd Lester will go over the sand budget. \nAnd I think that is my last slide. \nIt is. \nSo I’m going to do my best to stop sharing. \nAnd Jim\, I saw that you had a hand up. \nDid you want to quickly ask that question? \nAnd you’re on mute. \nI’m sorry\, I just must have bumped that button. \nI didn’t have a question. \nOh\, good\, thanks. \nSo that’s just a quick overview of where we are in case \nanybody’s new or has forgotten anything. \nAnd if there are any questions or thoughts at this time\, we’re \nhappy to entertain them. \nIf not\, we’ll turn the presentation over to Edwin. \nOK\, Edwin\, I think you Brenda. \nYep\, Sorry Brenda\, this is Jen CU at EPA. \nI do have a quick question and I’m haven’t really been involved \nin this conversation on the mining side more. \nI’m in the dredging world as you know why no work windows? \nWell\, the project proponents went through consultation with \nUS Fish and Wildlife Service\, NOAA Fisheries\, and they have an \nincidental take permit from California Department of Fish \nand Wildlife. \nAnd the biological pinions did not recommend work windows. \nThey did recommend fish screening\, but I think\, yeah\, I \nthink that’s that they did not find that it was necessary for \nthis activity and there is mitigation required of the \nminers to cover the incidental take of the mining activity. \nSo they did note there would be take\, but they did require \nmitigation. \nSo I think that is the best and simplest answer for now. \nThank you. \nWe can talk more later if you’d like. \nYou’re welcome. \nOK\, Edwin\, I think you are up. \nOK\, thank you. \nAnd let me try to get everything going here. \nOK\, we can see your slides and that’s in presenter view. \nDon’t know if you want to switch to full screen. \nOh\, how did I do that one? \nSo on my screen\, it’s full screen\, unfortunately. \nHey\, Edwin\, on the three dots\, the three dots on the right\, \nthere’s hide presenter view. \nThere you go. \nThat’s the one\, Marilyn. \nThank you. \nSo we always use Steam and not zoom in Europe. \nSo I guess that’s one of the differences between US and and \nEurope. \nI think you can all see the presentation now in\, in full \nscreen. \nYes\, thank you. \nWell\, let me first start with saying thank you for allowing us \nthis opportunity to present\, maybe explain some of the \nfindings we have. \nWe understood the\, the\, it’s\, it’s complex and we understand \nand we\, we also know that there are questions and hopefully we \ncan answer some. \nSo what I try to do is\, is just do a very general overview of \nthe work we’ve done\, the methods we used and also the reasoning \nbehind it because I think that’s the most important. \nThe work I’ve done is was done with a whole group of folks at \nDeltares with floor to Ruwink and myself being the principal \ninvestigators. \nYou may wonder why Deltares is involved because we are a Dutch \nbased well Research Foundation actually\, but we have a very \nstrong ties with San Francisco Bay. \nSo I was actually stationed there with uses for almost 11 \nyears doing a lot of work in the Bay Area and one of the first \nassignments I had with the sand waves in the Golden Gate region \nand it was maybe 15 years ago already. \nSo it’s a very interesting area and we’re very happy to \nparticipate in the research and hopefully we could contribute \nnicely to the cause. \nSo what I’ll present today is very briefly a our calls and \nobjectives. \nAnd well\, I’m not going to present the steady area\, you all \nknow it all too well. \nBut I will show you a little bit of the available data and then \nI’m going to jump to or I’m going to focus to the results \nfor West Central Bay. \nAnd that’s where I’m going to really try to explain the \nmethods and the the reasoning behind our analysis. \nAnd I’m going to run you through that for West Central Bay. \nAnd I also have some slides prepared for Sassoon Bay. \nBut that’s really the the findings. \nBut to make things a little bit more digestible\, because it’s a \nlot of different data\, a lot of different figures\, I try to \nfocus on West Central Bay to provide you with most of the \ninsights. \nSo let me just go to the next one. \nSo Brand already showed the overarching questions that were \nunderlying the research with the questions we were tasked to do \nwere actually 4 diff\, 4 different parts. \n1st is a very detailed analysis of the mining areas\, which we \ncall the ring analysis. \nSo I’m going to present the results of that one because I \nthink that will raise some questions from the descent \nminers specifically. \nSo I’m going to focus on those results quite a bit. \nThen we’re going to look into the bad forms\, bad for mobility \nbecause that allows us to tell to to maybe find relations \nbetween mining areas and the surrounding areas. \nThe same codes for larger scale base scale morpho\, morpho \ndynamic change. \nAn additional task we’ve done together with USDS was\, was from \nsediment transport pathway modelling. \nBut that’s not part of this research or at least not what I \npresent today. \nIf you look at the available data\, then we had\, we focus on\, \non basically two study sites. \nWe have West Central Bay and the Sassoon Bay and Middle Crown \nShoals. \nAnd the data we have is\, is actually five years of \nbathymetric surveys for West Central Bay between 1997 and \n2019. \nAnd in the Sassoon Bay and Middle Crown we had slightly \nless data. \nSo this is the data that we were able to work with. \nAnd so all of our findings\, all of our our real analysis is \nbased on this time frame. \nAnd if you really want to talk about base wide morphodynamic \nchange\, then of course this time frame is not long enough to \nresolve that. \nSo we need to do a lot of interpretation\, use expert \njudgement\, use other maybe other studies\, user experience in \nother systems to translate the findings from this from this \ndata to the overarching questions on what does this mean \nfor the overall settlement budget that Lester will present? \nOr also what does this mean in\, in the scope of sea level rise. \nThe data we have is is really\, really beautiful data. \nSo I really have to compliment you for the poor site in \nacquiring this data. \nIt’s not often that we have multi beam data available of \nsuch high resolution and quality that we can work with. \nAnd what you see on this screen is a is West Central Bay. \nSo the bathymetric maps based on that multi beam data that we \nmade in for the 1997 measurement that’s on the let me get a \npointer here. \nThat’s on the left panel. \nThis is the 1997 measurement. \nWhat you see here is the sea floor. \nIf you would drain the entire West central Bay. \nThe blue areas are the really deep areas and the yellow areas \nare the shallower areas\, the Shoals or the the rock \npinnacles. \nYou can see this in the 1997 bathymetry. \nYou can see this for the most recent bathymetry we have on the \nright. \nThat’s the 2019 bathymetry. \nAnd if you kind of look from a very broadly\, they look the \nsame. \nIt’s the same colour scheme. \nIt’s both blue\, it’s both yellow. \nIt’s\, but if you look in these maps\, you can also already see \nsome differences. \nOne of the one of the things you actually notice are for example\, \nthese really nice sand waves. \nSo that is the basis for our a platform analysis. \nAnd you can see these sand wave fields in both maps. \nSo it’s not that mining changed that system completely that sand \nwaves are not in the maps. \nBut you can also see some effects of mining. \nFor example\, if you look at these red dots\, those are mining \nlease areas\, and you can see that the bathymetry changed \nbetween 1997 and 2019. \nSo just looking\, glancing at these maps\, you can already see \nthat there is some effect of mining. \nBut what does this effect mean? \nWell\, to to really give you an answer\, that’s where we need a \nvery detailed analysis and it’s not as straightforward as you \nthink. \nIt’s not because you see that things change that you cannot \ncan automatically say it’s negative or positive. \nSo we need to be very objective in that just because it changed\, \nit doesn’t mean it’s a very negative thing. \nIt it all depends on what you want or what you yeah\, what you \nexpect from your from the mining effort. \nSo these maps are going to be\, you’re going to see them \nthroughout the presentation. \nSo if there are questions\, feel free to ask. \nBut I always use these colour schemes and kind of these \nvisualization techniques to show the data. \nSo Part 1 of the analysis that I’d like to explain is really \nthe local impact of mining. \nSo we’re going to focus on the lease areas and we’re going to \nreally try to quantify how much impact we have from mining on \nthe platform bathymetry. \nAnd to do this\, we use a method that was outlined by by E Track \nin back in 2018. \nThey called it the ring analysis. \nYou kind of see the principle in this plot where you see these \nlittle polygons around these bounding boxes\, around the \ndifferent lease areas. \nAnd in these bounding boxes you can compute the battimetric \nchange. \nSo based on the measurements\, we can compute how much battimetric \nchange we have based on the dredge record. \nWe can also compute how much was actually removed from these \nareas and the difference between the two. \nSo the ratio between the two\, that’s what we call the recovery \nfactor and that recovery factor that becomes really important in \nthe interpretation of the results. \nSo here are the ring polygons for West Central Bay and here \nyou in the bottom plot\, you can see that there is a similar \nanalysis for Sassoon Bay or for the Sassoon Channel. \nIf you look at the mind volumes within the lease areas in total \nover the 2000\, 8 to 2019 time frame\, we have 5 and a half \nmillion cubic cards of mining that takes place in the lease \nareas. \nBut unfortunately the ring polygons that we have our \nanalysis based on the ring polygons. \nIn the ring polygons we only observe 4.4 million of mining. \nSo it means that still within the lease area there is mining \noutside of the ring polygons. \nThat’s not a problem for in terms of the how do you call \nthat it’s\, it’s not a problem in terms of the mining. \nIt is within the lease areas. \nBut we were\, we were supposed or we were\, we were hoping to use \nthe ring polygons to quantify the chains. \nAnd we do this with two rings\, an inner and an outer ring. \nAnd that outer ring would help us define whether it’s a \ndiffusion effect where the mining will actually result in \nchanges outside the mined area. \nBut what we can see from these numbers is that the mining \ntracks actually go through these ring polygons. \nSo that analysis we couldn’t fully do the way we intended to \ndo. \nBut so we have five and a half million mined of which 4.4 \nmillion in those in the lease area according to the dredging \nrecords. \nIf you look at the mathematics\, we can do a similar exercise \nthat we take and I’ve tried to outline how we do this analysis. \nWe take the two bathymetries\, but this is for example the 1997 \nbathymetry\, again\, the 2019 bathymetry\, and then the \ndifference between these two bathymetries that gives us the \nvolumetric change within each of these rings. \nVolumetric change can be computed in two ways. \nWe can just look at the BET level difference between 2 maps \nor we can do something slightly different which we call a \nsediment thickness computation. \nAnd what we do is we take the the the whole sequence of maps. \nFrom these maps we create the minimum bathymetry\, so that is \nthe minimum depth observed throughout the time frame. \nAnd from that minimum depth\, we compute how much sediment is \nactually available in relation to that minimum bathymetry. \nAnd that’s what you see here. \nThat’s a sediment thickness map. \nThis is kind of a difficult topic. \nI think the most important thing to realize is that it does not \nmatter what method you use\, whether you just compute full \nmetric change based on that level change or whether you use \nthe method we did with sediment thickness. \nIt doesn’t matter for the end result\, the total change is \ncomplete is the same. \nThe only\, the only the reason why we use sediment thickness is \nbecause it gives us a little bit of more information. \nIt helps us to define not only the change\, but also how much \nsediment is actually present during that timeframe and where \nthe mining is a big portion or a small portion of the sediment \nthat was active in the total system. \nSo it gives us a little bit more information\, but it will not \nchange the findings of the volumetric analysis because of \nthat\, that mining that takes place outside of the ring \npolygons. \nWe used something we called an extended buffer analysis. \nWe use slightly larger areas to try to determine whether mining \nalso has a diffusive effect on the surroundings. \nSo if you do this analysis and now it’s a lot of numbers\, but \nthere are only two numbers that are really important. \nIf we do this analysis\, we can see that from the dredge records \nthere is 4.4 million mined in these different ring polygons. \nAnd from the bathymetric observations we observe a BET \nlevel change of 2.3 million. \nSo that means the BET lowered by 2.3 million\, but there was 4.4 \nmillion removed. \nSo there is approximately almost 50% recovery over all the lease \nareas. \nSo those holes that they dredge are filled in with sediments \neither from the ocean or its relic sand or its sand that’s \nalready in the system. \nBut there is recovery of those dredge\, the dredging of the \nmining areas. \nThe one thing you notice is if you look carefully in this table \nand over here you have the recovery rate. \nThis last column\, the recovery rate varies greatly between the \ndifferent lease areas. \nAnd what we observe is that there is a very different \nresponse between the northern lease areas versus the southern \nlease areas. \nSo the southern lease areas\, the ones on the procedure shall have \na very high recovery rate while the northern lease areas have a \nvery low recovery rate. \nAnd that becomes important in the interpretation of the \nresults. \nAnd I’m going to try to explain that very simplistic because I\, \nI always find it that this is sometimes this is this difficult \nconcept to grasp. \nSo what I’ve done here is I’ve just draw\, drew a box over San \nFrancisco Bay and I schematize that box into this vertical \ncolumn where I have water and where I have sediment. \nAnd if you have an inflow\, and this is a total hypothetical \ncase here\, this is not the segment budget that Lester will \npresent. \nBut if you have an inflow of 10 million cubic yards or just 10 \nas a number and we have an outflow of 10\, we can kind of \nschematize this in this box. \nAnd if there is an equilibrium state\, so if the bed level is in \nequilibrium to the water flow\, then if 10 comes in\, 10 will go \nout. \nThat’s kind of what this segment budget will tell you. \nSo what if we include mining? \nSo we still have 10 coming in\, but now we remove half of it \nthrough mining. \nWell\, we can actually have two responses. \nWe can have a bat lowering or we can have a reduced flow because \nthe total sum always needs to be the same. \nSo if we have bat lowering with no recovery\, so if the the \namount of mining results\, if you mine 5\,000\,000 cubic yards\, you \nremove 5 million from the bed and the bed lowers by 5 million\, \nthere is no recovery\, then the total sediment budget remains \nunchanged. \nSo there’s 10 coming in and there’s 10 going out. \nSo that’s important to realize. \nSo if you mine and there is no recovery\, the overall sediment \nbudget of the entire thing\, the amount of sediment moving to the \nocean in this case will not change. \nBut you have a local depth increase of the Bay. \nSo if you have high recovery\, for example if you have 100% \nrecovery\, you get the opposite response. \nSo there is still 10 coming in. \nYou remove 5. \nBut with 100% recovery the bet doesn’t lower. \nWhatever you removed is filled in by the sediment supply that \ncame in. \nSo that means that you’re going to change the sediment budget so \nless goes out. \nSo depending on the recovery\, you have a local impact\, you \nlower the BET or you have a large scale impact on the \nsettlement budget. \nSo that’s two very different responses and that’s important \nto realise whether and and you can base decisions on that. \nWhat do you think is important? \nIs this local depth increase? \nIs that important? \nThat’s well\, you can you can debate about that. \nIt’s not always the case. \nEven just because you have a local increase\, it doesn’t mean \nthat the system is negatively impacted. \nI’m going to try to explain that a little bit better in the next \nslides. \nSo if we zoom in on these protymetry\, so these are the \nexact same maps that I showed before\, Blue is still deeper\, \nyellow is still shallower. \nThis is Polygon one that is just South of Angel Island. \nThis is that Polygon 3. \nThis Polygon 1 is right over here. \nThis is spring Polygon 3. \nSo this is Angel Island is is located right here. \nBut if you look\, look in these two bathymetries where we have \nvery low recovery rates\, you can actually see that through \nbecause the mining and the spring Polygon\, the local bed \ndecreased in depth and it did not recover with sediments. \nSo now the question is\, is that important? \nWell\, if it’s not an important habitat\, if no one\, I don’t \nthink anyone will notice if you’re in -30 meters of water \ndepth\, if that depth increases by 1 meter\, is that a big impact \nor not? \nThat’s something you have to decide. \nIt’s not by definition a negative. \nIf it’s in the middle of the Bay\, you may say like OK\, that’s \nan acceptable loss or that’s an acceptable change. \nSo you have local bet loading\, but no or very low impact on the \nbase scale set in budget. \nIf you go to show to the lease areas on procedures sold\, for \nexample\, we see a completely opposite behaviour over here. \nWe see that you mine\, but you have a lot of recovery. \nAnd what you can see in these ring areas here is sometimes \nthese are all different observations through the \ndifferent\, different years. \nYou see that there is an impact of Miami. \nYou can see these little dredge holes\, but the next year they’re \nfilled in again. \nSo in this area\, the natural bat hardly is hardly affected. \nIf you kind of glance through your your eyes\, you can see that \nthe bat forms kind of move on. \nIt’s the same structure. \nThere is very small local impact\, but you did remove \nsediment from the system. \nSo that has an impact on the sediment budget. \nSo it’s a totally opposite reaction to sand mining. \nOK. \nSo that was the first part. \nI was just looking at very much in depth into the mining areas. \nAnd looking at how these mining areas respond differently with \nlow and high recovery rates\, but we also try to do see whether \nthe mining areas had an impact on the larger scale sediment \nbudget. \nAnd that’s where things become a little bit complicated because \nthe maps we have are really beautiful maps\, but they only \ncover a very small time span. \nAnd if you look on more for dynamic scales on larger areas\, \nit takes a long time for change to happen. \nSo often you cannot get directly get those effects from short \nterm data. \nBut we can look at all kinds of different indicators to see if \nwe can see impacts. \nOne of the things we did was an extended ring analysis. \nAnother thing we did was to quantify platforms and mobility \nand these platforms are really nicely illustrated here and we \ntry to understand the large scale settlement budget of West \nCentral Bay. \nAnd I’m going to go through these results very quickly. \nSo if there are questions please ask him or after the ask him \nafter the presentation. \nWe have a lot of different\, we performed a lot of different \nring analysis and we have lots and lots of plots. \nSo I’m only going to show one for and this is the one where we \nhad the most obvious results or the the result where we had the \nmost that we could analyse best. \nAnd that’s for ring Polygon one. \nSo the extended buffer analysis\, it basically just expands the \nthe ring Polycom that was drawn around the the mining area\, it \nexpands it with all the rings up to a distance of a kilometre \nalmost. \nAnd what you see in these colours\, the red colours are \nerosion. \nSo that’s bed loading and the green colours are accretion in \nthe bed. \nAnd what you can see in these\, in these maps and these are all \nthe different time intervals between the measurements\, you \ncan see that there is more erosion around the mining area \nsome. \nSo some of that limited recovery is probably a result of sand \nthat came in from the adiation shore. \nYou can see that here in most areas you have some red more \nredder colors around the the ring Polygon. \nBut we do have to state that the natural variability is probably \nreally large as well. \nAnd that will become apparent in the bathymetric change analysis \nthat the Bay itself responds yearly or the bat level in this \nin the Bay changes yearly depending on whether you had a \nhigh flow year or low flow year\, whether you had more wind or \nless wind. \nAnd there’s a lot of variability and you don’t fully capture that \nwith the six or the five parametric maps you had \navailable. \nSo we can say that there are indications that there is some \nsand moving around from the Shoal into the the area and that \ncontributes to that recovery. \nBut you cannot contribute all of the erosion you see to the \nmining activity. \nThat’s not a statement that we want to make. \nAnother aspect we we try to address is to see if platforms \ncan provide indications of of this larger scale effects. \nAnd what you can see is that here are the lease areas again\, \nbut you can see these really nice platform fields that are \nlocated close to the lease areas\, but close to a lease area \nis not in the lease area. \nSo unfortunately we can detect lots of platforms and that’s in \nthe next slide. \nWe can detect a lot of platforms throughout West Central Bay\, but \nnot exactly in the major lease areas. \nAnd part of that that this discrepancy is just because in \nthese major lease areas here. \nLet me just go back to this slide. \nIn this lease area you saw that the entire bed lowered because \nof the the mining\, there was less not a whole lot of \nrecovery. \nSo sand waves could not reform. \nSo we can get results for sand wave fields in the vicinity\, but \nnot directly in these lease areas. \nOver here we have a little bit more luck where the sand waves \nare overlapping with the the mining areas. \nSo we did a lot of analysis to compute the transport and \nmigration rates. \nAnd honestly the only real map that we can use to make \nstatistically meaningful correlations is the 2018 \nnineteen map because that’s the shortest interval between the \nmeasurements. \nIf you really may want to make these statistical correlations\, \neven though the maps you have are\, I know very costly to \nacquire\, it took a lot of effort to acquire\, but you would have \nto have a more frequent interval to really determine statistical \ncorrelations in the platform fields. \nBut even with those limitations\, we were able to derive the \nsediment transport directions and rates for quite a \nsubstantial portion of the Bay. \nAnd based on these platforms\, you can draw a couple of \nconclusions. \nWell\, I’ve tried to make this one here is that over here\, it \nbecomes quite difficult to link these platforms to these areas\, \nso I’m not going to do that. \nAnd you have these rock pinnacles separating the two. \nBut over here\, it becomes quite obvious that part of that high \nrecovery rate is probably because of these platform fields \nthat are from opposing directions\, which also mean that \nthere is a convergence of sediment. \nThere is a lot of sediment that will actually travel to that \nlocation and that explains why you have such high recovery in \nthis area. \nOK\, so in one last effort we try to do is to try to we try to \nlook at the larger scale segment budget based on these measures \nbetween 1997 and 2019 and try to link larger scale batymetric \nchange in relation to the mining areas and what you see in this \nplot. \nAll these little lines are artificial bounding boxes. \nFor each of these bounding boxes\, we computed the vertical \nchange\, and the vertical change is illustrated by these dots. \nThe larger dots show more vertical change. \nRed is negative\, that’s erosion\, and green is accretion. \nAnd what you can see that during a period of low mining \nintensity\, for example\, 2008\, 2014\, there was actually a \npositive\, mostly positive feedback of the bed. \nThe beds are created during a period of high mining intensity. \nAnd I’m\, the way I phrase it now is\, is I’m not suggesting \nanything. \nLet me\, I’m\, I’m going to come back to the words I’m going to \nsay now. \nBut during a period of high mining intensity\, we also see \nthat the entire West Central Bay was negative. \nThere was a lot of erosion and we are not going to jump to the \nconclusion that there is a link to the mining activity here. \nThe only thing we can say is that it’s very likely that \nthere’s a coincidence between this very high mining activity \nand during this time frame\, there was probably a very \nnegative balance of the Bay. \nSo maybe this was after major flood events or a dry period \nthat there was less sediment supply to the Bay\, but it’s not. \nWe cannot make the correlation between mining activity and \noverall response of the Bay. \nThat is just a coincidence that happens in these maps and we \ncannot make that. \nWe cannot conclude that that that there is a relation between \nthe two. \nI just wanted to make that clear because it’s very easy to \nmisread these figures in such a way. \nOK\, let me try to synthesize all of these results. \nI know it’s probably goes really fast and it’s a lot of \ninformation to digest. \nOne of the ways that I always use to try to\, to explain \nmorphodynamic change is using this sort of stepped approach \nwhere we\, we call this the scale cascade\, where we look at \ndifferent parts of the morphodynamics through time and \nspace. \nSo if we want to answer questions for the entire San \nFrancisco Bay\, well\, we cannot do that based on this study. \nWe need the settlement budget of lesser. \nYou need to do a full budget of the Bay and it’s going to take \ndecades to centuries to for the entire Bay to respond to morpho \ndynamic change. \nAnd what we’ve done is we analyzed mining events or a \ncouple of mining events. \nSo that’s completely on this spectrum of the Bay. \nBut through careful analysis and through expert judgment\, you can \nmake links from the smallest scale\, from the mining events to \nthe impacts on the large scale settlement budgets. \nSo one of the things we notice that on the smallest scale\, you \ncan always see the impact of mining in the form of potholes. \nThose always seem to appear and depending on the recovery those \nfill in very quickly procedures show for example or they don’t \nfill in at all. \nAnd what happens then is then with the reoccurring mining then \nthe all of the potholes combined cause a depression in the \nunderlying show that on the time scale we looked at could not \nrecover fully. \nSo that show for example\, in ring Polygon tree\, this feature \nover here that in our measurements that completely \ndisappeared because of the mining effects. \nBut maybe that’s not too bad that this Shoal is very far \noffshore in the middle of the Bay. \nSo the impact of a disappearing Shoal is very low. \nIf you deepen the Bay in this part\, maybe by half a meter\, it \nwill not affect the waves near San Francisco. \nIf you really deepen Presidious Shoal where we actually saw that \nthere was very high recovery\, then you would have an indirect \nimpact maybe on the shoreline. \nIf you deepen the shore the the Shoals\, then the waves that can \npropagate to the coast can actually become higher. \nSo the low versus high recovery is actually in a quite \nconvenient location in terms of indirect effects. \nDeepening something that’s already really deep is less \ncumbersome than deepening something that is shallow and \nactually shelters the the shoreline that’s been needed. \nSo in that respect\, the low versus high recovery seems to \nwork quite well. \nWell\, I think I covered most of the these these topics so on. \nSo depending on the recovery\, you can have an impact locally \nor you can have an impact on the larger scale. \nIf the recovery rates are low\, as I mentioned before\, then the \ntotal settlement budget is less influenced and but that’s all \nwithin reason. \nSo at some point\, if you keep stretching\, if you completely \ndeepen the entire Bay by meters and meters\, so you have much \nmore tidal volume going in and out\, then of course you’re going \nto change the tides in San Francisco Bay. \nSo at some point you’re going to reach a tipping point that it \nbecomes too deep and then it becomes a problem what that \ntipping point is. \nWell\, we can tell you you would need very careful modelling. \nBut I’m I can reassure you that the tipping point is probably \nnowhere not reached right now. \nAnd it’s very not even close to a tipping point because that’s \nthe the mining is too small scale for the the in relation to \nthe total sediment volume of the Bay to really have a major \nimpact on tidal propagation right now. \nIf you ask the same question in 100 years\, I may give you a \ndifferent answer if you continue operations because then you \nremoved 100 times that 5 million or 20 times the 5 million \nbecause it was a five year interval. \nSo\, but at the moment that all seems that to me that did not \nappear to be the biggest issue. \nSo if you remove sediments from an area that with high recovery \nrates and obviously you do you do impact the sediment transport \nsystems and then you can can create the sediment difference \ndifferent deficit somewhere else in the Bay or you may reduce the \nsediment supply to the to the outer coast. \nThis last point is maybe a little bit counterintuitive. \nWhat I tried to say here is that if you remove sand\, sometimes \nit’s not completely apparent because you create a hole and \nthat hole can be filled in with silt. \nSo then the sand budget remains unchanged. \nThe sediment budget of course remains negative because it’s \nfilled in with mud\, with a different material. \nAnd as mud shows a very strong or fast response that can all \nthat can that that process can happen quickly\, but you would \nalter the Bay floor composition\, which as a habitat may not be \nthe best or may may have and one wanted effect. \nI think that were the main points I wanted to make at West \nCentral Bay. \nMaybe maybe I should ask Brenda this one. \nWe can have a little pause for questions because I’m sure there \nare questions about the method and the the results. \nI also have some additional slides for the Sassoon channel \nnot displaying the method\, but just showing the pure results in \nterms of volume and butymetric change of the Sassoon channel. \nSo whatever you prefer. \nYeah\, thank you so much\, Edwin. \nThis was really helpful and I hope informative for everybody. \nI think we should probably turn now to questions and discussion \nfor a few minutes because it is almost 11. \nI think we got a little bit of a slow start this morning. \nSo I think I first need to do 2 things. \nOne\, if everybody could please take a minute and just add your \nname and affiliation in the chat because we do want to make sure \neverybody who has joined is on the is on the interested parties \nlist\, especially if you’re new to the group. \nSo please take a moment for that. \nSorry\, I meant mentioned earlier\, but in the meantime\, \nErica and Bill and Aaron\, did you have some comments you \nwanted to share at this time? \nAnd you’re all on mute. \nSo hi\, Brenda\, this is Erica. \nWell\, I guess Aaron\, do you want to step in? \nWell\, yeah\, I always think we’re just gonna say no\, no comments \nfrom us\, but we would like to see the results on Sassoon Bay \npresented because I think that’s important for Lynn Marine is \nthat the that’s where they do their mining. \nSo I think that’s where we’d like to see the the time spent. \nOK\, I think we do. \nWe have a fair amount of time for the the budget conversation. \nSo perhaps\, Edwin\, I don’t know how quickly you can do that \nwithout turning all of our heads around in a circle. \nBut maybe if you could take 5 minutes or so and just run us \nthrough so soon\, that would be very helpful. \nThank you. \nSure\, but the now I have to find the share button again. \nOh\, sorry. \nIt should be at the bottom of your screen. \nNo\, no\, no\, I I caught it. \nI got it. \nI caught it. \nYou can of course\, we’re going to run into the issue of the \npresenter mode\, but I think we resolved that better button. \nThree buttons again and then height. \nYep\, there you go. \nI should have left\, I should have left this on screen\, but my \napologies. \nSo this will be a very quick presentation because all the \nmethods and all the the techniques we did are the same. \nOne of the things you can clearly see in the Sassoon \nchannel is that is the the effect of mining you can see in \nthe we have we have less bathymetry. \nSee\, well\, what we’re looking at here is a 2014\, 18 and 19 \nbathymetry. \nAgain\, it’s the same colour scheme with blue with the deeper \nchannel\, and yellow is the shallower part of the channel. \nAnd you can also see these red lines or the outlines of where \nyou have the water versus dry land. \nYou can see that the multi beam doesn’t cover the entire reach \nof the river\, but what you can see in the mining area\, that’s \nthe red dot. \nLet me get the pointer. \nYou can see in 2014 it wasn’t mined a whole lot\, but in 2018 \nand 19 you can see the cumulative effects of potholing. \nBasically you can see all these little dots which are basically \nindividual mining events that create a depression in the bed. \nAnd if you subtract the two bathymetry\, so you do\, if you do \na 2019 minus the 2014 bathymetry\, you kind of get this \nresult where the light yellow colours are a small amount of \nerosion. \nAnd the darker it gets\, the higher the erosion value \nbecomes. \nSo you can see this depression\, you can clearly see it in the \nthe area. \nSo you see a deepening of the mining location\, but what you \ncan also see is that the entire channel deepens and it deepens \non both sides. \nSo it’s not. \nAnd from that observation alone\, you can already tell that mining \nis probably not the main factor in this overall deepening of the \nentire channel. \nIt’s not that you capture all the sediment in the mining area \nand that’s why the adjacent areas are depleted\, because then \nyou would have a bias to the upstream or downstream side. \nSo apparently the entire system is just has lowered because of \nthe probably the\, the\, the\, the amount of drainage from the \nSacramento River. \nAnd that was also one of the underlying arguments why we say \nthat in West Central Bay that overall lowering of the Bay is \nprobably not due to mining because we also saw it in the \nsystem channel. \nSo in the bathymetry’s you can kind of see that same response \nwith low recovery. \nSorry\, I need to go do this a bit faster. \nAnd that’s what was. \nIf you really zoom into that area\, so now I’m just going and \nI just went to the ring polygons\, you can really see \nthat potholing. \nYou can also see that the mining volumes\, which I summarized in \nthis table are a lot lower compared to the the volumes from \nCentral Bay. \nBut the vertical change in this ring Polygon was actually quite \nsubstantially\, almost 2 1/2 meters. \nUnfortunately\, in this area we could not identify bat forms \nvery close to the the mining area. \nWe did define some bat forms\, but they were quite far away. \nSo any bat form analysis in relation to the mining areas\, we \ncould not do in this. \nIn this area. \nFrom the pics you can see that the recovery rates are quite \nlow\, 1% actually between 2014 and 2019. \nAnd if you look at mining impact on a slightly larger scale\, we \ndid this extended ring analysis again. \nWell\, you can see that the ring Polygon itself\, it’s dark red. \nYou see that in the channel there is overall erosion. \nBut as I mentioned before\, the entire multi beam area actually \nshows erosion. \nSo we\, we can’t conclude that mining is the the main actor in \nthis erosional process. \nI think that are the results that I wanted to present quickly \nfor Sasume. \nOh\, actually I\, I\, I have one more slide. \nI guess I did not prepare the additional slides as thorough as \nthoroughly as I should have done. \nBut in this slide\, it’s the same sediment budget analysis as we \ndid for Central Bay. \nSo we looked at the ring polygons\, we identified other \nsimilar polygons\, computed the volumetric change and you can \nsee that everything is negative with the largest negative or the \nlargest vertical change in the mining areas. \nThe low recovery rates also suggest that\, OK\, it’s a large \nlocal impact\, but on the overall transport rates\, it’s probably \nit did not\, probably didn’t change too much because whatever \nyou took out\, that’s also the amount that bet lowered and you \ndid not. \nSo therefore you didn’t affect the overall settlement budget. \nAnd I think that were the main conclusions here. \nI hope that helps a little bit. \nThank you\, Edwin. \nOK. \nSo I think we can open it up to questions assuming Erin and \nErica and Bill that you don’t have anything further to say at \nthis time. \nYeah\, nothing further\, Brenda\, thank you. \nOK\, So being commissioners\, if you have questions\, you’re up \nfirst and the group beyond that will try to keep us moving just \nbecause we are a little over time. \nSo Andy Gunther\, it looks like you have your hand up first. \nThanks\, Brenda. \nYeah\, so I have two questions. \nThanks so much for this. \nA lot of information crammed into a a\, a\, a elegant \npresentation. \nFirst question is on the Sassoon end. \nSo as I understood that we take sand out and we see the hole \nthat we left and we also see that there are changes in the \nsymmetry there that happened across the whole system. \nSo I am familiar with the old saying from the river \ngeomorphologists\, which is that 5% of the flow carries 95% of \nthe sediment in the river. \nAnd So what I’m wondering is in a major event like the 9798 San \nJoaquin flood or something like that\, could we theoretically\, \nfrom what you understand\, kind of reform the whole bottom of of \nthat area so that in an essence the holes would fill in in one \nepisode of of or is that do we not move sand in that way \nthrough the system? \nI think your 5% is moved by the big storms analogy is quite \ngood. \nSo yeah\, if you have a major flood event\, you may be fill in \nthose holes. \nThere is\, there’s a lot of material moving around the major \nflood events\, but the scale of such events should be\, I don’t \nknow. \nI don’t know if that’s a one in 100 year flood or whether that’s \na one in a 10 year flood or whether the time frame we looked \nat because it’s a very limited time frame. \nAnd yeah\, I know your periods of drought and and maybe flooding \nevents are also on that same time scale. \nSo it’s possible that what we are looking at right now is just \na consequence of the five years of maybe low flow conditions and \nnot a whole lot of movement. \nSo I think your hypothesis could very well be be true\, I think. \nBut I\, I would say folks like Dave Schulheimer will probably \nknow a little bit better on how much how\, how much sediment is \nactually moved in suspension. \nBut yeah\, I wouldn’t\, I wouldn’t be surprised that during major \nflood events a lot of infill would occur. \nBut it seems to me as we’re working here in preparation of \ncoming before the Commission with another permit\, which \nBrenda has a term of 10 years. \nYeah\, it yes. \nWell\, the previous permit had a 10 year. \nSo\, so I\, I wanna be sure that we understand where we might be \njust looking at\, in our permit scale at\, at\, at A\, at trying to \nunderstand changes in the bed that actually happen on a \ndecadal\, decadal scales. \nAnd we shouldn’t just assume what we see is always gonna be \nthere. \nSo that\, that’s what was one response to the Sassoon. \nAndy\, can I also have Dave speak to this? \nBecause I think Dave does have some expertise and there have \nbeen some differences found from the river flow concept that I \nthink we’re looking forward deferring to Dave on questions \nlike this. \nAnd I’m happy to do so again. \nYes\, I think it’s important. \nAnd also note that 19/8\, the 2018 to 2019 bathymetry was \nspecifically done to try to capture those wet years because \nwe had a couple wet years. \nAnd also note that we have bathymetry from 1997 to 2023. \nSo we’ve got 2 decades in there. \nDave\, up to you. \nOK. \nThe short answer\, Commissioner Gunther\, is that in Sassoon Bay\, \nlooking at the total sediment supply\, not just sand but for \nall of sediment that the typical dry year or normal year\, there’s \na slight bit of sediment accumulation in Sassoon Bay \nbeing at the upper end of the estuary. \nBut during the really wet years\, the 2000 sixes and I think it \nwas 2017\, then we see a net export of sediment from Sassoon \nBay. \nSo it’s actually the large years move out the sediment \nessentially as the soon Bay becomes fresh and potentially \neven at Mallard Island anyway\, more like the river\, we lose \nsediment. \nSo most years there’s a small amount of total accumulation. \nAnd then in the really wet years\, we see some erosion \ntaking place\, Right\, right. \nBut as we’re thinking about the impact of the area that’s mined \nit\, it seems to me like we have a situation where as we dig \nthese holes\, those areas become much more hungry for sediment \nand sand. \nAnd you could have a situation with in a big year. \nAnd I see Lester’s telling me 2017 was already was a big year. \nAnd I\, I\, I\, I would\, I’m not exactly sure how the water flow \nrelates to the force that is coming through the Sassoon \nregion. \nBut we still could have a situation\, couldn’t we\, Dave? \nWhere you where these these holes we’ve dug fill in? \nEven though the total transport situation is as you describe\, \nthe velocity given that these holes question perhaps Edwin \ncould address is that given that these holes are in the channel\, \nthere may be sufficient velocity there to prevent them\, prevent \nthe finer sediments from filling in. \nMost of these sediments coming in during the high flows are \ngonna be very fine sediments\, not the sand. \nSo\, Edwin\, I don’t know if you my\, my\, my gut feeling is that \nthe currents in in those holes are large enough where you’re \nnot going to fill them up with a bunch of mud. \nThey’re gonna remain as holes for the fines. \nIndeed. \nYeah\, Yeah. \nAnd the and for the the core sands\, I\, I think if there’s \nsand that can be moved around\, then you create a large hole \nthat’s suitable for the position. \nTheoretically it could fill in\, but we did not see it in the \nlimited observations we had. \nAnd if it fills in\, of course\, then it’s an additional deficit \nto the Oval settlement budget. \nAnd I think also one of the observations from your work \nheadwind that was really key was just the really very few bed 4\, \nbut seemingly very little sand transport in Sassoon Bay\, which \nimplies that those holes are not going to fill in with sand. \nThere just isn’t much sand moving there. \nThey’re not gonna fill in easily\, not under the conditions \nthat we had during these measurements. \nSo I think that’s a very clear observation. \nAm I correct then that this would be a hypothesis we could \ntest with ongoing monitoring during the period that we might \nbe conducting mining? \nWe know where these holes are now we can go look and see \nwhat’s going on. \nOK. \nI want to move down to the Presidio Shoal where I have \nanother question\, which as as you described\, we have bed forms \ncoming in both directions and that seems to imply there’s \nmovement that fills up the holes we dig. \nSo as I understood what you said\, that would be very\, very \nimportant with regards to the wave regime on the shoreline \nthere. \nIf we if we dug holes and it just got deeper and deeper\, we \ncould influence the erosion. \nOK. \nSo that’s an important thing for us to understand that happens \nnow as the way I’m seeing it\, and this is\, I’m glad we have \nthese. \nI don’t have to do this kind of thing before the whole \nCommission. \nIf we didn’t mine\, the sand wouldn’t pile up there\, right? \nSo\, so in essence\, we are taking sand from somewhere. \nWe just don’t know where it would have gone if we hadn’t \npulled it out ourselves. \nOK\, thanks. \nCorrect. \nAnd if I can add a little bit to that 1\, So it’s a very active \nsediment regime over there\, a lot of sand moving around. \nYou take out a little bit and we cannot see any observations. \nWe cannot see a clear correlation that well\, we took \nsome out. \nSo now we see more erosion here. \nAnd that’s where that remarks comes in that you created the \ndeficit\, but it’s possible that that deficit is filled in by \nfine sediments in shallower regions. \nFor example\, if a lot of that sand was transported into South \nBay\, you create a deficit in South Bay. \nAnd then in South Bay is you have a very nice place where \nfines can settle. \nSo then that accommodation space can be filled in with fines \ndeposition for the overall settlement budget. \nThat’s still negative\, but you wouldn’t directly see it in the \nsand budget\, right? \nBut there’s right\, but there we are even if we’re changing the \nform of the Mass\, we’re still conserving Mass here. \nSo\, so it that there\, there if we did a hole and there’s no \nhole when we go back a year later\, then then we have the \nthat material that deposited there would have gone somewhere \nelse because it won’t pile up. \nYeah\, OK\, thanks. \nAnd I’ll just add that I think\, and I would look to Mike Bishop \nperhaps to give us a nod on this\, that it’s these areas are \nnot filling up with fines because they keep going back to \nget sand and they keep finding sand. \nThat’s why they keep going back to the same locations. \nSo we’re not to the best of my knowledge\, and again\, Mike\, \ncorrect me\, we are not seeing it go from sand to fines at this \ntime. \nThat would be correct. \nThank you. \nMike\, I understand what’s happening. \nPat\, I see your hand up. \nThank you\, Edward. \nI really appreciated this\, this presentation. \nAs Andrew said\, it was very elegant and and really helpful. \nThere was one slide you went over much too fast for me\, \nactually several\, but anyway\, particularly one that showed it \nhad some black lines. \nIt was over kind of the whole Bay Area\, the whole Bay sediment \nit had had some black lines. \nWhat do those black lines mean? \nI think the arrow transport is what you’re referring to. \nYeah\, I but I’m not sure what the arrow transport of what can \nyou go back to that? \nShould should I just share my screen quickly? \nYes\, please. \nYeah\, I think this is the slide. \nDo you figure you were referring to? \nThis is the one so\, but you can see in this figure\, I’m going to \ntry to blow it up a little bit. \nSo this is one of the figures you made to that in order to \nconceptually understand the sediment transports that are \ngoing on in relation to the platform fields and what these \nblack arrows mean. \nThese are the the high energetic tides that push in and out of \nthe Golden Cate and that are capable of transporting large \namounts of sediments if they are available. \nSo this whole area in the direct vicinity of the Golden Kate\, \nincluding this lease area\, is probably fed by sediments that \npush in and out of the Golden Kate. \nBut there isn’t a whole lot of sediment here. \nSo that may be one of the reasons why you don’t have a lot \nof refill in this area. \nWhat you can\, what you can see here are these major platforms\, \nthis entire Shoal area\, these platforms are likely linked to \nthe flow acceleration around Angel Island and that kind of \ncreates these platforms. \nBut these platforms do not link up with these these areas \nbecause they’re these are kind of linked to this process. \nAnd that’s the other reason why this sediment won’t travel\, at \nleast not in the time span of the observations to this area \nwithin the in our reports\, we try to conceptually describe \nthis. \nAnd I just pulled one of the figures. \nMy apologies for not explaining it too well. \nThis is a very oh\, no\, no\, that’s\, that’s that’s very \nhelpful. \nSo in other words\, in a\, in this year\, the transport was very \nmuch from the Golden Gate into the Bay. \nWell\, it’s always like that. \nYou always have on these flood deltas\, that’s the area we call \nhere that is directly influenced by the tides pushing in and out \nof the Golden Gate. \nThat’s the flood delta that’s always influenced by the \nsediment transport from the Golden Gate. \nBut apparently not. \nThere isn’t enough to refill this mining area completely. \nSo that part is on this these time scales\, it’s apparently \nlimited. \nAnd over here\, it’s a completely different story because this is \nhas both sediment transports tides pushing in and out of the \nGolden Gate. \nYou have the waves going along the along the coast. \nSo there’s a lot of littoral transport here. \nThere’s tides going back and forth into South Bay. \nAnd all of these combined give a lot of energy to the sediment \ntransport. \nSo you have a lot of movement and high recovery in this area. \nThat’s our conception. \nYou\, you can explain those differences. \nThank you. \nThat’s very helpful. \nRight. \nOK. \nI have Jim’s hand up and I think this is going to be our last \nquestion. \nSo we make sure we have time to get into the sand budget. \nI think we’re still OK\, but let’s try to wrap this piece up \nand move on\, please. \nThank you. \nThanks. \nFascinating stuff and I’ve been around this stuff for a while. \nI hope you’ve all seen my letter of July 14th. \nI did try to collect observations. \nI’ve got 2 augmentations here which are based on direct \nobservation. \nI\, I used to race windsurfers at\, at\, at in front of the Saint \nFrancis every other Friday night in between races. \nWe would kind of hang out on the\, on the submerged beach in \nfront of the seawall there. \nThere was sediment and\, and transport\, literal transport \ncooking by us at a remarkable rate. \nAnd there’s a\, there’s a difference between the transport \nmechanisms along the shoreline\, which are literal and are one \nway driven. \nAnd you can get a budget for that from the the tip Shoal \ndredging at the mouth of the Marina\, the time it took to \nrefill the sub aerial deposition when they opened a an increase \nin the tidal prism at the at\, at at the Golden Gate National \nRecreational Area\, Presidio shallow. \nPresidio Shoal is shallow enough and fed. \nAnd I think there’s ample background information to know \nthat you’ve got sediment coming in from the ocean and\, and it \ngoes in one\, One Direction. \nThat’s very different transport mechanism than in the center of \nthe basin. \nYou have to have a Shoal which is shallow enough for wave \nenergy to\, to disturb it and start it into the literal \nprocess. \nBut a fascinating presentation. \nThe the the one point I wanted to make is that the redeposition \nand refilling of the Presidio Shoal. \nDoesn’t surprise me at all. \nThere’s a lot of literal way of energy. \nThank you. \nThose observations are always the best. \nThe observations from the field and if they correspond with the \nfindings\, that’s even better. \nSo thank you for your remarks. \nOK\, Thank you so much\, Edwin. \nSo I just want to remind folks that if they want to read the \nfull study and you should because there’s a whole lot more \ninformation on it. \nIt is in Appendix G of the sand findings report. \nIt is the second study in order of Appendix G And I think with \nthat\, Edwin\, thank you so very much. \nWe appreciate all the work you’ve done on this front and \ncoming to present today. \nAnd I’m going to turn it over to Lester McKee. \nAnd while Lester is warming up\, I’ll just let folks know that \nour next meeting\, we will have Michael McWilliams presenting on \nsand transport modeling\, which will be even more information \nand fun. \nSo get ready for that. \nIt’s coming up soon. \nOK\, Lester\, we see your slides in presenter view. \nThank you. \nAnd you’re on mute. \nThe little microphone button should be at the bottom of your \nslides. \nGot it. \nYou’re off. \nHere you go. \nSo anyway\, I got the same problem as Edwin that that \nyou’re seeing or are you seeing it in the in the appropriate \nview? \nIt’s in the perfect view. \nYou’ve got it all straight. \nThanks\, Lester. \nOK\, great. \nWell\, thanks everybody. \nAgain\, my name is Lester McKee. \nI’m a senior scientist with San Francisco SG Institute. \nI’ve been studying sediments in the Bay and it’s watersheds now \nsince the year 2000. \nAnd it’s a pleasure to assist you in this conversation about \nhow sand moves around in the Bay. \nLet’s see\, can we advance the slide? \nHow do we do that? \nHere we go. \nSo just start off with a quick primer on what is a sediment \nbudget. \nIt’s a statement of the net quantity of sediment deposited \nor eroded in a system balanced against the sum of sources and \nexternal sinks. \nJust to remind you that mass must be conserved\, and I think \nEdwin made this point very clearly. \nThat is\, inflow minus outflow must equal the change in the \nstorage that we observe in the system. \nSo just repeating that again for a given control volume and \nperiod of time\, and we need to define both of those change in \nthe bed. \nFunctionally a change in elevation\, but it could also be \na change in density or grain size or other things. \nBut functionally a change in elevation must equal inflow \nminus outflow. \nSo it follows that if inflows are smaller than outflows\, then \nbed erosion must be observed in the system. \nI want to make this last point loud and clear. \nA sediment budget does not account for any sediment outside \nthe control volume. \nThat is all the sediment that’s stored in the Bay. \nThis is this other sediment is deemed permanently stored and \nnot dynamically in transport night\, not dynamically part of \nthe sediment budget. \nAnd I’ll make that point a few times more in the presentation. \nSo in our Bay\, we set up a conceptual model to describe the \ninflow terms\, the way sediment is coming into the Bay and to \ndescribe the way sediment is leaving the Bay\, the outflow \nterms\, and these are the listed inflow and outflow terms you can \nsee that includes sand mining and dredging and wetland reuse \nand wetland deposition and tidal flood control channel removal on \nthe outflows. \nAnd for inflows\, it’s the typical inflows we would see \ninto an estuary system inflow from our tributaries\, in this \ncase the broader Central Valley tributaries as well as local \ntributaries. \nAnd then as being discussed already\, this littoral transport \nthat occurs from what from wave forces along the beachfronts. \nWe also quantified the net change in the system that is the \nbaffinetric change and that was largely facilitated by work of \nBruce Jeff Jaffe and his team at USGS. \nAnd then there is a a transport mechanism they of moving \nsediment around by dredge materials disposal that is from \none pay part of the Bay to the other. \nBut in this case\, it’s not a loss or a gain term\, but rather \na just a movement of sediment from one place in inside the \ncontrol volume to another place inside the control volume. \nLet’s see if I can move. \nThere we go. \nSo in our case\, inflow and outflow and bed storage chains \nchange terms are all quantified such that we could rearrange the \nconservation of mass equation to estimate the exchange for the \nPacific Ocean boundary. \nWe had no a priori assumption that it would be either in or \nout\, but rather the the budget would determine the net \ntransport direction. \nSo that that term is an unknown term in the budget and is done \nby subtraction. \nIt’s the\, it’s the balance of the inflows and the outflows. \nI want to point out that there is very good certainty in the \nsand mining numbers that we received from the sand mining \ncommunity and also the dredging numbers that we get from the \nLTMS work. \nSo the disposal and beneficial youth numbers are all well \nquantified. \nHowever\, the other terms are less certain\, but we estimated \nthem using the best of\, say\, available science and the \nmethods and the results are well documented in the technical \nreports that have been produced either through the study or in \npast studies. \nSo I want to move now to just helping us to understand what a \nsettlement budget is lesser\, Never mind\, sorry\, I was going \nto say your slides weren’t moving\, but they just did. \nI apologize. \nOK\, so to help us understand how our Senate budget works\, let’s \ntake a hypothetical example. \nAnd this is actually similar to what Edwin described\, but let’s \njust run over it again. \nLet’s assume that as there’s zero inflows from our tributary. \nSo in our diagram there you see zero input from the inflows and \nlet’s assume that there’s half a million metric tons of outflow \nby sand mining or dredging. \nFrom a simple sand budget standpoint\, the Bay doesn’t \nreally care\, but there was some outflow that was caused by \noccurred from a removal. \nSo in our hypothetical example here\, if we measured 0 metric\, 0 \nmillion metric tons of sediment erosion from the bed\, then since \nmass must be conserved to develop to\, to balance this \nbudget\, there would need to be a half million metric tons flowing \nout through the Golden Gate\, sorry\, flow in through the \nGolden Gate from the Pacific Ocean. \nAnd so you can see there a simple budget. \nNow if we take the same hypothetical example and find \nthat in fact\, there had been some bed lowering during that \nsame. \nAnd let’s assume that it’s that it’s half a million as well\, \nsince mass must be conserved to balance the budget. \nNow there would need to be lesser amount flow in from the \nocean because that was accommodated by a bed reduction \nand the bed elevation. \nIn this hypothetical case\, the bed lowering balances the sand \nout flow by dredging or mining. \nAnd so there would be 0 in the exchange with the situation \nthrough the Golden Gate Bridge. \nAnd so that helps you perhaps to understand how the budget \nconservation and mass concept works. \nNow\, if we take the same hypothetical example and find \nthat in fact there is some additional supply from the \ntributaries\, and let’s just pretend it’s 0.25 million metric \ntons per year during that same period. \nSince mass must be conserved to balance this budget\, there would \nneed to be a greater amount flow to the ocean\, in this \nhypothetical case 0.25\, to balance out the budget\, and that \nwould flow out through the Golden Gate to the Pacific \nOcean. \nSo I hope these examples help you to understand how the \ninterim budget works. \nInflow or outflow through the Golden Gate from or to the \nPacific Coast as a result of the sum of all the inflow minus the \nsum of all the outflows. \nSo you can think of the outflow term as a Ledger\, an account of \nthe fate of the inflowing sediment in any sediment that is \neroded from the bed\, that is the total mass that’s in transport \nin this budget. \nTo note\, because there is no change of stand storage in the \nwater column\, that is we observed no trend in the \nconcentration during the budget period\, there is no partitioning \nof the changes in storage terms between the bed and the water \ncolumn. \nSo in our case\, our budget is actually a bed sediment budget. \nIt’s an accounting of the fate. \nThat is what happens to the bed sediment and that additional \ninflow from the watersheds during the budget period. \nSo now let’s talk about our assumptions for the budget. \nWe call this the control volume. \nIt’s the boundary contention and assumptions that set up the \nconstruct of the mathematical budget. \nSo the spatial scale and extent that we included was everywhere \ndownstream from the Meladon cross section\, essentially just \ndownstream from the the confluence of the Sacramento and \nSan Raquin River systems all the way through to the Golden Gate \nBridge. \nConceptually\, the cross section that’s underneath the Golden \nGate Bridge\, we included everything that is below head of \ntide\, that is everything that we think the tides are interacting \nand moving sentiment around. \nWe assumed in this case that wetland deposition is \npermanently stored and we are able to make that assumption \nbecause we’re talking about a net process and our observations \nin the Bay Area right now suggest that our wetlands are \nstill in the net depositional state. \nIn the future that could change. \nBut right now for this 20 year budget period\, we assumed that \nsentiment that moved into the wetlands is permanently stored. \nAnd the accounting. \nWe chose was the period where there’s the most and best \nquality data available which was 2001 to 2020. \nThat’s a 20 year. \nAnd the active bid is any sediment that is exposed to \nestrogen currents that is in transport at any time during the \naccounting. \nAnd so that’s what we call the active bid. \nThat is the part of the the bid landscape that is part of the \nbudget. \nSo now let’s move on to some results. \nYou can see now that we have different size arrows on this \ndiagram and those represent a relationship between the size of \ntransport for each of the different inflow and outflow \nterms. \nThey’re not actually ranked on the basis of mass\, they’re \nranked on the basis of order. \nSo don’t take this the actual areas of those areas to be \nperfect indication of mass\, but they give you a relative \nrelationship between the different inflow and outflow \nterms. \nWhat you can see from this diagram\, this is the hull based \nstand settlement budget is that the outflow is the the sand \nmining is the largest outflow and it’s the second largest term \nin the budget. \nI need to wharfed a little bit by the change in and best metric \nchange. \nIt is roughly equivalent to the other slightly larger term best \nmetric change. \nAnd so if we think about it\, there’s a temptation to explore \nwhat would happen to the budget if we were to turn off sand \nmining by making it zero if one were to do this for the 20 year \naccounting using the simple math\, it wood forest an increase \nin sediment outflow from the system. \nBut that assumes that there’s no other changes that would occur \nif such a event if we were to turn off the send mining. \nBut this may or may not actually occur. \nThe system could also respond by less space metric change as \nEdwin had discussed in the previous previous Pres Pres \npresentation. \nIn this case\, if we accounted for it all in a change change in \nthe bathymetric change\, then it would be just .13 million\, the \ndifference between 1.33 and 1.2. \nOr it may cause a requirement for navigational dredging \nsomewhere else. \nOr it might change the literal sand transport into the system \nfrom the Pacific Coast. \nOr it may also increase the sand supply to beaches. \nBut one cannot say from the budget\, but what one can say is \nas a large term and most certainly has an influence on \nthe system. \nIn contrast\, if we were to turn off one of the smaller terms\, \nfor example\, stop issuing permits with the flood control \nagencies to dredge their settlement locally\, we’d like to \nsee a net gain in elevation in the flood control channels. \nWe could see local flooding as a result. \nWe could see some supply to the changing supply to the mud flats \nlocally or to the wetlands locally\, but except at that very \nlocal temporal and spatial scale\, this would likely be \ndifficult to measure. \nBut mass must be conserved and so we would know that it would \nbe there somewhere. \nWe would rightly conclude that sediment removal by flood \ncontrol agencies has virtually no influence on the system wide \nor the large scale budget\, in stark contrast to the larger \nbudget term of sand mining\, which we can say most certainly \nhas a large influence from the budget. \nBut from a budget standpoint we can’t say exactly what that \ninfluence would be. \nSo now if we look at the sand mining\, sorry\, the sand \nsettlement budget for the Sun Bay\, we see a similar \nconclusion. \nSand mining is the largest term in the budget. \nWe can say it has a large effect but had not occurred during the \nbudget period. \nThere are a variety of options for the fate of that segment \nthat may have allowed bid gain to the bed to gain elevation. \nIt may have caused the need for more navigational dredging\, or \nit may have caused an increase in flux out to some Pablo Bay\, \nfor example. \nThat other very large arrow in this diagram we cannot say\, but \nwe can say it has a large influence in the budget\, unlike \nthe other smaller terms in the budget. \nNow if we look at the sand sediment budget that stands \nCentral Bay\, we we have a similar situation. \nSand mining is also the largest term in this budget. \nWe can say it has a large effect at the scale\, at the local scale \nof the mining leases where there were in some cases only partial \nreplenishment\, the bid level lowered by meters over the \ndecade with large morphologic\, morphologic disruption. \nSo that’s what Edwin described\, but if it had not occurred \nduring the budget\, there are a variety of options for the fate \nof that sediment. \nIt may have allowed the bed to gain meters of elevation in the \nlease areas or if averaged across the House of abatement \nand about 1.8mm of bed elevation gain could have occurred. \nOr it may have caused the need for more navigational dredging \nor may have caused a reduction in flux from San Pablo Bay or \nfrom the South Bay. \nYou can see there’s some large arrows on the top left hand side \nof this diagram that that potentially could have changed \nor it may have caused an increase in flux towards the \nPacific Ocean. \nWe cannot say from the budget\, but we can say it has a large \ninfluence on the budget\, unlike the smaller terms. \nSo now to the the questions that were asked in the primary for \nthis meeting. \nHow much sand is there in the Bay? \nDuring the 2001 to 2020 budget\, we can say that .545 million \nmetric tons per year of sediment came into the Bay from the \ntributaries and from littoral sand transport along the \nbeachfront in the Presidio\, and 1.33 million metric tons of sand \nwas sourced from the bed of the Bay. \nThe sum of the amount of sand that was in the Bay during this \n2001 period from the budget standpoint was the sum of those \ntwo terms .45 + 1.33 or 1.78 million metric tons. \nSo that is the that is the the sediment amount per year that \nthen needed to be accounted for that needed to be. \nWe need to determine what the fate of it was during the budget \nperiod. \nAnd all those arrows on the on the outflow terms on this \ndiagram show that the fate of that sediment\, this of course is \nthis slide here is talking about the whole Bay. \nThat last slide was just giving the central Bay example. \nI want to emphasize that we did not report legacy sediment that \nis outside of our control volume. \nThat is the sediment below the active bed stored in wetlands or \nin beach and dune deposits around the Bay. \nThese pools are in permanent storage from a budget \nstandpoint\, as we define the control volumes and not actively \ncontributing to the same transport in the budget. \nThe volumes in these pools are massive compared to the budget. \nI want to give an example of just how massive. \nIf we think about the surface area of the bed of the Bay\, it’s \nabout 1200 square kilometers\, square kilometers in that 1200 \nsquare kilometers in the 1m top 1 meter of that sediment\, \nthere’s about 300 million metric tons of sand and permanent \nstorage. \nFrom the standpoint of this budget\, if we assume an average \nbulk density of about 820 kilograms per meter cubed and \naverage sand content of about 30%. \nSo I want to if says again\, we did not include this and S&S \nand budget\, these volumes are massive compared to the amount \nof sand that’s in\, in movement in in the control volume. \nSo how does mining affect the budget? \nIt was the second question in the in the in the outline for \nthis discussion. \nToday\, sand mining is the largest term in the meta scale \nwhole Bay sand budget and in the macro scale the soon and central \npaid Bay budgets. \nMining undoubtedly has an influence on the Bay morpho \ndynamics at these scales. \nIf sand mining were to be turned off\, or maybe just a change\, a \nchange in the volumes either increase or decrease. \nSince sand mining is a large term\, there would be large \nchanges to other elements in the budget\, but which other elements \nwould change and the amount of change for each individual \nelement are unknown. \nBut mass must be conserved\, and so there would be. \nA concomitant amount of change in the other budget elements \nthat must add up to the change that we would would see from \neither turning off or changing the thin mining volumes. \nSo thanks very much. \nThat’s the summary of the SAN budget for the Bay. \nWith that I’m willing to take questions. \nThank you\, Lester. \nSo I guess at this point\, we will again open up the \npresentation to the sand miners. \nAnd Erica. \nAaron\, Bill\, Mike\, did you have comments you wanted to provide? \nThis is Bill. \nYeah\, I think Aaron\, Aaron has some comments that that he would \nlike to provide on behalf of the miners. \nThank you. \nSure. \nI’m going to go ahead and share my screen. \nCould you stop sharing Lester\, please? \nIt says I can’t share while someone else is sharing. \nThank you. \nYep\, there we go. \nOK\, I’m going to cover. \nLet me just click through a couple slides. \nWe just want to cover a few main points\, one of them Lester made. \nBut the important part we want to emphasize is that the sand \nbudget is really a balance of the sand that’s moving in and \nout of the system\, but it doesn’t include that large \nreservoir sand. \nSo you know you wouldn’t apply it like you would a a financial \nbudget and how much you’re going to spend this year and next year \netcetera. \nSo that for that exercise\, you need to take into account this \nsize of the large sand reservoir. \nAnd then the next key point we want to make has to do with the \nuncertainty. \nSo there is a lot of parameters that go into that sand budget \nand the conversation of mass and all those different inputs and \noutputs have their uncertainties. \nAnd so because of the methods applied and assuming it’s all a \nconnected system\, those uncertainties accumulate \nthroughout the Bay until you end up at that Golden Gate boundary \nflux. \nAnd so the the results at that Golden Gate boundary end up \nhaving\, you know\, a significant uncertainty between the upper \nand lower values. \nSo the lower\, lower end of the values is actually a flux into \nthe Bay of 0.66 million metric tons per year. \nThe upper estimate is 1.1 million metric tons out of the \nBay with the best estimate at 0.25. \nSo that’s an uncertainty of\, you know\, over 300%. \nSo the things that make up that uncertainty are described in \nLesser’s report. \nSo bathymetric change is the big one. \nSo there’s a lot of uncertainty and all the different surveys \nthat were used with different methods over different time \nperiods. \nSo we understand that in the methods applied\, the sand budget \nvariation or variability accounts for a 50% uncertainty \nin that bathymetric change. \nBut the USGS reports that\, oh\, it could be up to 100%. \nSo that’s the largest and most uncertain term in the budget and \nhas A and significantly influences the the results \nincluding the flux at the Bay. \nDry bulk density is another one. \nI think it was assumed that sand was a\, a single dry bulk density \nfor all the sand in the Bay\, which we think there’s\, it’s\, \nit’s probably more complicated than that. \nAnd then the other important point we want to make is that if \nthere’s a lot of sand moving in and out of the Bay\, you know\, \nit’s\, it was described in the strategic stratigraphy report in \nthe last working group that there’s a\, a large sand \nreservoir that extends\, you know\, on either side of the \nGolden Gate Bridge. \nAnd\, you know\, in Lesser’s report\, he highlights that \nbidirectional fluxes are 10 times greater than the net flux. \nSo we’re talking about a large amount of sand moving both ways. \nAnd what’s reported in the sand budget is kind of the net. \nSo the net is a fraction of what’s moving in and out of the \nBay. \nAnd given that uncertainty\, we don’t really know which way it’s \ngoing. \nSo on in\, you know\, the span of\, you know\, years to decades\, you \nknow\, that could fluctuate one way or the other given the \nuncertainties. \nAnd then the last point we want to make\, we appreciate the time \nwe got to spend with the researchers in the ISP \nunderstanding the methods a little better. \nBut one of the issues we have is that the bathymetric change and \nthe mining\, you know\, are are are linked and the studies point \nto\, you know\, both the Deltares maps we’re looking at here and \nthe USGS maps we’re looking at is that mining significantly \naffects the bathymetric change at the local scale. \nSo it’s not as simple as if you turned off mining\, you’d have \nall this extra sand\, you know\, going out elsewhere throughout \nthe Bay. \nYou know\, what would happen is that you’d have a lot less \nbathymetric change. \nSo it’s important that to highlight that a lot of this \nmining happens at at a depth that that sand would not \notherwise be mobilized. \nYou know\, a lot of that active sediment and change occurs\, you \nknow\, in the in the upper layers as you see throughout the Bay\, \nyou know\, plus or minus a meter\, whereas the mining areas are \ngoing down several meters deep into that layer of sand below \nthe active bed. \nSo we\, we think that’s an important point when you’re \nstarting to pick and choose which variables you’re adjusting \nin the sand budget. \nSo that wraps up our our comments on this study. \nOK\, maybe I don’t know\, Lester\, before we go to Commissioner \nquestions\, Lester\, if you wanted to respond to any of that or if \nBob or Dave wanted to respond or Craig\, we also have Craig here \nthis morning. \nSo if you’d like to respond\, feel free. \nAnd I see Lester\, your hand is up. \nYeah\, just quickly\, Aaron\, nothing you just said bothered \nme. \nI\, I don’t find any\, any\, any inaccuracies in what you just \nsaid. \nI do acknowledge that there is an uncertainty in the flux at \nthe Golden Gate. \nAnd what we did in our report was we gave a worst case \nscenario. \nAnd so I do agree that the air bands are very\, very large for \nthe worst case scenario. \nBut that was done through a sensitivity analysis\, not \nthrough an air analysis. \nAnd so the sensitivity analysis gives the worst case scenario. \nIt it assumes that all the inflow terms were maximized and \nall the outflow terms were minimized to give a worst case \nscenario. \nAnd then you do the opposite and you go through that process \niteratively determined that the potential range of the of the \nflux into and out of the system at that unknown term. \nI would submit that the uncertainty in that number is \nprobably a lot smaller than that\, but we just can’t quantify \nit because a classic error analysis could not be done. \nSo the .25 at is our best judgment of the of the of of the \ncentral tendency of the data. \nThe the best estimate that I do acknowledge that there is \nuncertainty that probably includes the potential for flux \ninto the system. \nBut it’s it’s it’s all well documented what we did. \nAnd and I and I do acknowledge that that’s the term that has \nall the uncertainty piled into it. \nThank you\, Lester. \nCraig\, did you want to comment? \nAnd yeah\, and maybe I just want to punt this a little bit to set \nEdwin up to answer this. \nYou made a statement there at the end\, Edwin or I’m sorry\, \nAaron\, that without mining we simply wouldn’t have a change\, \nwhich seems to suggest that you believe that definitively if \nthere was no mining\, It’s all relic sand and that control \nvolume. \nI think what we’re seeing is actually that that that mining \nof sand is on the order of what Lester is seeing for other \nsediment inflows. \nSo I\, you know\, I feel like that that final statement is a little \nbit of a definitive statement that might mischaracterize what \nwe know. \nWe don’t know if we stopped the mining\, what would happen to \nthat bathymetric change in the Bay. \nAnd we don’t know that without that mining\, it wouldn’t have \nany effect on the overall budget. \nI\, I think that’s a bit of an oversimplification. \nAnd Edwin\, I think you\, you touched on that a bit of what we \ndo and don’t know regarding bathymetric change. \nSo I might unto you for that. \nI’m not sure if I can give you the right answer. \nI\, I\, I did like\, actually like\, I appreciated the comments of \nthe descent miners actually\, because we’re trying to\, to\, to\, \nmaybe to\, to\, to give an analysis that also kind of \nconfirms what they’re saying as well. \nSo if you just look at the mathematical settlement budget\, \nwhatever you take out is always negative. \nBut the mining also has a lot of positives. \nThere’s an economic value\, there’s the sand is a resource \nand you cannot just look at the negative and the sentiment \nbudget alone. \nYou also have to look at what is the impact maybe locally. \nSo locally mining has an impact. \nIf there’s no recovery\, it deepens the bed. \nBut as Aaron\, I think really nicely mentioned is that there \nis a huge amount of sediment available. \nAnd is that deepening of the bed such a negative effect that you \nactually think it’s a negative or is it just taking out a \nlittle bit of sediment that was already there? \nAnd it’s substantial if you look at the total bathymetric change \nbecause the\, the the Bay is relatively in equilibrium. \nSo whatever you take out\, you it stands out\, but it doesn’t mean \nthat you’re distorting the entire system. \nIt’s\, it’s in the amount that moves. \nIt’s substantial\, but it’s a huge reservoir of sand \navailable. \nAnd that’s also what we’re trying to or at least try to \naddress that depending on the location\, whether you have high \nor low recovery\, you have a slightly different impact that \nyou may or may not feel is important. \nAnd that that’s kind of the the reasoning I tried to outline in \nmy presentation. \nI’m not sure if that really helped answer Craig’s question. \nThanks\, Edwin. \nAnd I’m going to go to Bob and then Andy and Barry. \nSo I do see your hands. \nBut I’m gonna let the independent science panel \nrespond again first. \nBob. \nYeah. \nThanks\, Brenda. \nHopefully you can’t hear this rock’n’roll music at the coffee \nshop that I’m at. \nNope. \nYeah. \nI just wanted to say I put some comments in the chat. \nI wanted to point out that the ring analysis would be useful to \nidentify the local changes in the sand mining areas that \nCommissioner Gunther mentioned and I think if that can that was \nextended into the future that could help look at this question \nabout large slugs of deposition etcetera. \nSo I think that’s a good tool. \nSecondly\, Commissioner Schollwalter mentioned\, you know \nthe question about the big black arrows and I appreciated the \nclarification that we were only looking at part of the littoral \ncell the there. \nThe literature indicates that the sand that the Central Bay \nShoals and the mining areas occupy are part of a system that \nincludes the Ed bars outside of the Golden Gate and San \nFrancisco Bay all the way down to Pacifica. \nSo that’s if they’re all LinkedIn in a sense. \nThird\, we did correlate changes out at the San Francisco Bar in \nOcean Beach with changes at Chrissy Field indicating \nsomewhere around a 30 year lag in terms of a large slug input \nand accretion at Chrissy Field. \nAnd I\, I put in the chat a couple of papers that I’ve \nwritten on that topic. \nThank you. \nThanks\, Bob And I as I turn it over to Andy for his question. \nI also just want to remind folks that one of the reasons we did \nmultiple studies is to get multiple lines of evidence that \nhelp us understand what this all means\, right? \nOne study doesn’t answer at all. \nAnd so we are literally pulling information from different \nstudies to kind of get an understanding of the system. \nAnd if you think back to our meeting in July\, the provenance \nwork helped us understand that the Sassoon sand is separate \nfrom the Central Bay sand\, right? \nIt’s no longer connected. \nAnd so that speaks to some of what Bob just mentioned about \nthe outer coast connection to Central Bay because there is a \nstrong connection shown there in the Providence work and the \nProvidence work talked about Sassoon Bay having some \ndifferent origins at this point in time and age. \nAnd with that\, Andy\, thanks Brenda. \nOne question for Lester\, and it’s about the use of the word \nsand and the word sediment and the the OR and then sand \nsediment. \nAnd I verify that there was you were like when you refer to \nterms such as the material dredged by the flood control \nagencies\, you’re doing some kind of grain size correction there \nor something to just figure out the sand. \nThey’re taking that total sediment\, Yes. \nOK\, great. \nThanks. \nAnd I just want to thank everybody for the the \nparticularly the our our independent science panel \nmembers. \nThe there’s a lot of trying to make sense out of this is a \nchallenge. \nThis is a regular been a regular occurrence in my career. \nEvery time anyone studies anything at the Golden Gate\, \nwhether it’s the any movement of any particles there is \noverwhelmed by the\, the\, the daily versus the net transport. \nAnd it’s a very challenging topic. \nAnd I hope as we go forward here we can\, it seems to me we’re \nalready framing the\, the\, there are both short term impacts. \nThen there’s also things we have to watch for in maybe a two or \nthree permit frame at in order to make sure that we’re not \ncreating some kind of cumulative impact. \nAnd then also this idea that there are certain episodes might \nreset the system in\, in\, in a way. \nAnd that we\, these are their\, their\, I would like the staff to \nreally think about this as we go forward\, is that there are \nthings that we’re\, we’re identifying that we’re\, we’re \nreally not going to be able to make any kind of definitive \nstatements about. \nAnd\, and so\, so\, but we that doesn’t mean we will never know \nabout these things. \nAnd\, and any kind of work\, any kind of permit work permitting \ngoing forward should really try and hone in on how we can use \nongoing monitoring to\, to work on particular issues and not \nlose these questions\, you know\, 10 years hand. \nSo that we’re really refining our understanding as we go \nforward. \nThanks. \nThank you\, Andy. \nJust in response to that\, a brief response. \nSo on the big reset to the system\, there are other studies \nthat can help us understand that\, that are not in this \ncollection of the five to seven studies we did. \nSo if you were to look at Bruce Jaffe’s work on Babe Athemetery \nfrom 1850 to today\, right before he retired and left me\, I’m so \nsad You don’t see a big reset of the system. \nYou do see net erosional and net deposition\, but what you don’t \nsee is a big reset to the system. \nWhat he was able to tract was sediment moving out of the \nsystem from the gold rush. \nAnd so I think\, you know\, we need to be cognizant of other \ninformation that’s available. \nWhat we’re presenting in this set of series is the recent work \nthat was done\, which is the best and latest technology and \nability to study this work. \nI mean\, one of the reasons why Middle Ground Shoal only has two \nsurveys is because the technology had to catch up with \nbeing able to do bathymetry in shallow water at an affordable \nrate. \nWe can now do that. \nWe couldn’t do that before 2014 or so. \nSo but we will be looking to other lines of evidence as well \nto help us understand the context and what’s all which \nthese studies fit you citing Bruce’s work did did was he \ndifferentiating sediment and silt and mud and clay. \nIt’s\, it’s bathymetric change overall\, but you can see whether \nthe set the system is resetting through flooding. \nWe\, we know the areas where the sand is so we can\, we can look \nto those to help us understand if in\, you know\, those time \nframes we’re seeing resets of the system. \nIs it time to have the public comment? \nOh\, Pat\, you’re keeping track. \nThank you. \nYes. \nIs there any public comment? \nWait\, didn’t Barry have a comment? \nDid you guys hand down? \nI think you may be answered his question. \nOh\, actually I’m not sure how my hand dropped down. \nI just\, I don’t know. \nThank. \nThanks\, Brenda. \nI wanted to follow up on the exchange between Aaron and I \nthink it was Bob who responded about the\, the\, the\, the\, the \neffect of bathymity with regard to dredging. \nAnd I want to tie it. \nI want to tie it back to what we heard at our last meeting where \nwe learned that one of the the one of the things that’s clear \nabout the majority of the sand we’re dredging out of the system \nis that it’s relic sand. \nI assumed that that that reinforced Aaron’s conclusion \nthat most of the net effect of dredging is deepening of \nbathymetry. \nBob\, I think it was you who said that that wasn’t entirely clear \nfrom the\, the work we’re discussing today. \nAnd I just wanted to ask if you could tie those two threads of \nevidence together. \nWas that for me? \nI’m yeah\, it\, it was\, it was\, I think it was you who had that \nexchange with Aaron. \nWell\, actually I’m not sure\, but I’ll just say that we did have \na\, a discussion ISP sand miners and\, and lesser and GHD. \nAnd I think we addressed the question about the double \ncounting. \nAnd I don’t think that’s a question anymore\, although I \nthink it was a good question. \nAnd\, and I’m not sure what could\, could you repeat the \nother two questions that you had? \nOh\, I\, you know\, I\, I my one of the conclusion I\, I our \nconclusions I reached from our last meeting was that if most of \nwhat we’re dredging is relics\, and that that the net effect of \ndredging is gonna be deepening of bathymetry. \nAnd perhaps it wasn’t you\, Bob\, I apologize\, but someone said \nthat it wasn’t entirely clear that was the case. \nYeah\, I could address that and I’ll let someone else. \nThere is relic sand in the mining areas based on available \ninformation and the the certigraphy fingerprinting \nstudy\, but that there is also relic sand in motion through the \ngolden gates. \nSo one of the confusing aspects is that we have relic sand \nthat’s moving now. \nAnd so it’s not\, they’re not exclusive relic. \nAnd and in transport almost all the sand is relic essentially. \nBut I think the question is if you excavate sand from below the \nbed\, do you have no effect on the surface sands that are being \nin transport? \nAnd I think that’s a really good question. \nHowever\, where they’re sand mining\, we do see the bed \nlowering and changing. \nSo in our view\, the surface is being changed and I’ll just \nleave it at that that that and I don’t if anyone else wants to \njump in\, Edwin\, go ahead. \nSorry\, I couldn’t find the hand in the in the system. \nSo actually I do\, I do think that you have a point about \nrelic sand in terms of the lease number of lease areas. \nIt’s probably not evenly distributed. \nYou have number of lease areas where it’s very active\, but the \nthe etching volumes are quite a lot lower in those areas. \nThe areas with hydrates volume are probably in the areas with \nless sediment activity. \nSo you’re more likely to mine relic sand. \nSo in terms of the total volume\, you’re probably right. \nYeah. \nAnd Edwin\, just for your background with the provenance \nwork\, what the University of Texas\, Texas at Austin found was \nis that the age of the sand and its origins basically say that \nthe sand was laid down at the last Ice Age in Central Bay and \nis a pool between the ocean and Central Bay\, and it’s all that \nvery old sand. \nAnd then Sassoon has slightly newer but also very old sand and \nthere doesn’t seem to be recent sand being deposited. \nAnd I’m not gonna define recent off the top of my head\, but I \nthink the general conclusion was is that all of the sand is truly \nconsidered relic sand. \nAnd so we should probably step away from those terms and talk \nabout sand in transport versus sand in place\, movement versus \nnot movement\, I think would be a better way to think about it in \nour framing for the conversation now\, because I think we have \npretty fairly definitive information that says this is \nall very old sand. \nAnd I’m happy to hear disagreement with that. \nBut I think that’s what the study tells us at large. \nThanks\, Brenda. \nYep. \nOK\, public comment if any. \nI think we’ve stunned everybody into silence. \nOK\, so last call\, I don’t see any hands. \nSo thank you. \nYes\, sorry\, I just had a quick question actually for Lester and \nI’m I’m one of the permanent council for the sand miners and \nreally appreciate the presentation. \nThis has all been fantastic. \nIt’s\, you know\, a lot of information and\, and\, and solid \nanalysis. \nBut I did want to ask there seem to be\, and I think this is \ngetting to some of the questions from Barry and others last year. \nThere’s a slightly different statement that I thought I heard \nfrom\, from your presentation and from Edwin’s that Edwin was \nseemed to be saying that if you’re removing sand from the \nbed\, but it’s not an act of transport that it’s possible \nthat you’re really not affecting the budget. \nAnd then I’m hearing you instead say that that it has a\, it \ncould\, it would have a significant impact on the \nbudget. \nBut I’m wondering if you would comment on what does that mean \nto the to when you say significant impact on other \nterms of the budget\, I’m assuming that that means that \nfor example\, you could just simply have a change in \nbathymetry. \nIt doesn’t necessarily mean an adverse change elsewhere in the \nsystem. \nAnd I want wanted to just confirm that that’s what what \nyou mean by significant impact or significant effect on other \nterms. \nAnd I think you’re muted. \nYeah\, you’re muted. \nYou gotta unmute bottom left corner of your screen just it \njust depends on where. \nYeah. \nSo thanks for that question. \nI think it’s a question of scale and time. \nBut remember the settlement budget is a blunt tool\, it’s an \naverage annual tool and it’s a miss balance tool. \nSo it demands that if you change one term\, some other terms\, one \nor two terms must change. \nSo I think what we’re trying to say is that if you do change the \nthe volume or mass removed by one of the terms\, for example \nsand mining\, then it’s going to demand in the budget that some \nother terms change in the mass balance. \nI think it’s more likely that if you\, for example\, were to mine \nless sentiment from a\, from a mining lease area\, it’s more \nlikely that the\, that the immediate impact would be a \nchange in the symmetry in that lease area. \nBut over a 20 year. \nOr a 40 year. \nOr some other longer time period\, you could get a cascade \nof a six. \nThat is that you could initially have a change in one element \nthat then might translate into a change in another element. \nAnd the budget\, the the toolbox that’s called the budget is is \ntoo blunt to predict which other terms would change and when and \nby what magnitude. \nBut the budget does suggest that they would change\, but we can’t \nsay when and by how much and which terms exactly. \nSo does that\, does that help help to answer? \nYou would use other tools to to get those questions. \nThe type of tools that Edwin described or modeling tools are \nexamples. \nThe budget could also be refined to be a more\, to be a less blunt \ntool. \nFor example\, we could do if we had more detailed information\, \nwe could do budgets for shorter time periods or smaller spatial \nscales. \nAnd as Edwin described\, you know\, you can do a budget right \ndown to the to the the footprint of a mining event. \nSo\, so you could use a budget tool to to get down to some of \nthose more nuanced answers to the to the question\, how would \nthe system change? \nBut this annual average 20 year budget at a whole system scale \ndoesn’t tell you can’t tell you exactly what the changes would \nbe and when and how they would temporally and spatially \narrange. \nThat’s helpful. \nThank you. \nPat\, you’ve got your hand back up. \nYes\, I do. \nI just one thing I think might make it a little easier for us \nto understand sort of the magnitude of everything is for \nyou to put a number in that box of the approximate amount of \nsand that’s in the Bay total. \nBecause when we look at that\, we don’t really have a feel for \nwe’re just talking about the change\, right? \nWe’re not talking about how big the system is that that change \nis on. \nSo I think that’s another thing to fit for us to think about in \nthe future is\, you know\, how big is the the sediment storage box \nof the Bay total? \nAnd you mentioned that it was massive and you and you gave a \nfigure\, but I think making that a little more prominent would be \nuseful anyway. \nSo that’s\, that’s just a comment. \nMay I\, may I respond to that just by saying we would have to \nthen decide what we include. \nDo we include all the wetlands? \nDo we include all the same beaches? \nDo we include just the 1m depth of the Bay or is it 10 \ncentimeters depth of the Bay or is it 10 meters depth of the \nBay? \nAnd so you get into the OR\, or the whole earth because actually \nthe reality is that the\, the sediment and storage is\, is \nessentially the lithos lithosphere of the Earth. \nYou know\, how\, how do you have\, you know\, and I’m perhaps being \na little bit silly to point out that\, you know\, the\, the\, the\, \nthe\, the geologic substrate of the Bay is a big\, big volume \nnumber. \nAnd\, and I can’t remember that off the top of my head. \nHow much stand is deposited in the Bay? \nBut I think it’s\, I think there’s evidence that in some \nareas it’s literally 100 meters of\, of\, of\, of\, of mud\, sandy \nmud sitting underneath the Bay. \nSo\, so I couldn’t put a number on this figure without a lot of \ninput from the independent science panel panel and from the \nbroader sediment community. \nSo while I gave an example of 300 million\, it was just to show \nyou that it’s a big\, big\, big number. \nWell\, that’s great. \nAnd Lester\, I think that my question sort of as a policy \nmaker here and your answer as a scientist is really that really \ndemonstrates the difficulty of converting this information and \nmaking it honest and to information that we can use. \nAnd so that was one of the things I wanted to talk about as \nto close this meeting. \nWhat is being done here is actually very difficult \nintellectually and conceptually. \nAnd I really appreciate all of the effort that has gone into \nnot only collecting this information\, but massaging it \nand\, and analysing it and organizing it in ways that you \ncan explain it to people who are not part of your field because \nthat’s when it becomes\, you know\, so useful. \nAnd so anyway\, I appreciate you doing that. \nAnd\, and it’s good to find out why. \nWell\, that simple suggestion I had turns out to not be a good \nidea. \nOK\, good to know. \nBut I\, I didn’t say it wasn’t a good idea. \nRather\, I just said it’s a difficult number to give you \nwithout. \nThat’s that’s what I mean. \nBut it’s not\, it’s not something you can just\, you can just add\, \nyou know\, it’s a\, it’s a hard thing and it’s\, it’s probably \noutside of the scope of what we’re doing right now. \nSo that’s OK. \nI I mean\, it’s good for me to know that. \nSo for all I really need to know is it’s a massive amount. \nThat’s the answer really. \nI need to know it’s a massive amount. \nOK\, yeah. \nI don’t need to put a number on it. \nAnd\, and we did try to\, we looked at the concept of doing \ndeep sediment cores in the area of the sand mining activity to \nfigure out how deep it was and if it was sand layers or sand \nand mud layers. \nAnd that would have taken our entire $1.2 million budget just \nto get the cores. \nNot a good idea\, but we couldn’t do it. \nMaybe we’ll do it next time\, who knows? \nBut I also will just say Edwin and Lester and Bob and Dave and \nCraig\, they all make it look so easy\, right? \nThey do. \nAnd we all know that’s not true. \nThat’s not true. \nSo anyway\, with that\, I think we can\, I want to thank everybody \nagain for their contributions to this science and this and\, and \nanswering these real life questions for us. \nAnd we’ll look forward to our next meeting. \nDo we have a date for that\, Brenda? \nYeah\, it’s coming up really soon. \nWe have two close together. \nSo I believe it’s September 4th. \nIs it Kat is. \nThank you\, Kat\, for nodding your head. \nI believe it is also from 11:50. \nOK. \nSo we’ll see you back here in a matter of a couple of weeks \nafter Labor Day. \nAnd upcoming is if you think this was fun\, just wait for \nMichael McWilliams and sediment transport modeling. \nIt’s a\, it’s a what Evan Edwin did and more so\, so we can talk \nabout flow now. \nWell\, from my point of view\, this was both fascinating and \nfun because I was learning so much. \nSo thank you to everybody. \nAnd with that\, I think the meeting’s adjourned. URL:https://www.bcdc.ca.gov/event/august-21-2024-sand-studies-commissioner-working-group/ CATEGORIES:Sand Studies Commissioner Working Group END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/Los_Angeles:20240712T130000 DTEND;TZID=America/Los_Angeles:20240712T150000 DTSTAMP:20260624T062646 CREATED:20240627T204823Z LAST-MODIFIED:20240910T182356Z UID:10000183-1720789200-1720796400@www.bcdc.ca.gov SUMMARY:July 12\, 2024 Sand Studies Commissioner Working Group DESCRIPTION:Join the meeting via ZOOM \nhttps://bcdc-ca-gov.zoom.us/j/85242441227?pwd=cvLg32wxpb1sszECxNgjXF3mbHzdLX.1 \nSee information on public participation \nTeleconference numbers(888) 278-0296(214) 765-0479Conference Code 900680 \nMeeting ID852 4244 1227 \nPasscode767485 \nIf you call in by telephone: \nPress *6 to unmute or mute yourselfPress *9 to raise your hand or lower your hand to speak \n \n \n \n \n Agenda\n \nWelcome and IntroductionsPatricia Showalter (Chair) will open the meeting and conduct commissioner roll-call.\n Context SettingStaff will review the agenda and meeting ground rules. They will give a general overview of the catalysts behind the current sand mining studies and Commissioner Working Group meetings\, including project permitting\, history\, and management questions the studies would be addressing.(Brenda Goeden) [415/352-3623; brenda.goeden@bcdc.ca.gov]Presentation\nFindings ReportIndependent Science Panel (ISP) members will review the findings of the ISP Sand Mining Summary Report as they pertain to Regional and Local Scale impacts of sand mining in the Bay.(Brenda Goeden) [415/352-3623; brenda.goeden@bcdc.ca.gov]Presentation // Mining representatives concerns on sand budget\nCommission Question 1 – Is the Bay Sand Relic or in Transport?Review findings of University of Texas at Austin Fingerprinting Study and its relevance to this question\, and policies questions related to this finding.(Brenda Goeden) [415/352-3623; brenda.goeden@bcdc.ca.gov]Presentation\nPublic Comment\nAdjournment\n\n \n \n \n \n \n Meeting recording\n \n \n\nTranscript\n\nYes. \nWell\, I see there’s a lot of people joining us. \nThat’s great. \nIt looks very hot where Ben is. \nThey do not yet see Greg up. \nThere’s Greg\, and it looks like Andy Gunther’s having a little \ntrouble connecting. \nOh\, he’s connected now. \nHe got connected. \nLooks like Barry’s there. \nSo I think we have Erica. \nBill\, There’s Bill. \nOK\, Bill\, it feels so long since I’ve seen you saw him yesterday \nand the day before. \nOK\, I think we should probably go ahead and get started. \nWe got a pack schedule. \nSo Pat\, if you’d like to open the meeting. \nYes\, Well\, welcome everybody. \nMy name is Pat Showalter and I’m the chair of the Sand Studies \nCommissioner Working Group. \nAnd we are here to review some really new information that has \nbeen put together and\, and\, and kind of ask questions and\, and \nabsorb as much of it as we possibly can so it can be used \nin the policy making process. \nAnd I\, I wanna extend a\, a just a warm welcome and thank you to \neveryone for taking part and particularly to the scientists \nwho have made this information come together. \nI know it’s having worked in the Bay for many\, many years. \nI know that understanding of the sand budget has has not been \nsomething that there’s a lot of information on over the years. \nAnd so I’m really excited to\, to to be here to learn more about \nthis. \nSo with that\, I think the next item is to just have a roll call \nof our\, the commissioners who are official members\, members of \nthis group. \nWe’d really\, we’re we’re glad for everybody else to be here \nand we\, you know\, depending on how it works\, we’ll run this \nfairly informally so everybody can ask questions as we go \nalong. \nIf it if that doesn’t work\, we’ll we’ll have to change to a \npublic comment period\, but I I doubt that’ll be necessary\, but \nwe’ll see how it goes. \nAnyway\, I’m Pat Showalter and let’s have a roll call for the \nother commissioners\, Commissioner Barry Nelson. \nBarry Nelson\, Commissioner and member of the working group. \nCommissioner Andrew Gunther. \nHi\, Andy Gunther. \nI’m a member of the working group and now in BCDC because \nI’m a member of the regional Mariapoli Control Board and \nchair Pat Showalter here. \nAll commissioners are present. \nEight. \nOK. \nAnd we’ll just quickly introduce the BCDC staff. \nAnd I think what we will also do is since there’s a fairly large \ngroup of folks\, if you can\, oh\, the BCDC staff and if everybody \nelse can put their name and affiliation in the chat\, that \nwould be really helpful. \nYes\, I think if we went to individual introductions\, that \nmight take us a while. \nAnd so I’m Brenda Gaten\, I’m the sediment program manager for \nBCDC. \nGreg\, you want to go next? \nSure. \nI’m Greg Scharf. \nI’m general counsel for BCDC. \nHarriet. \nI’m Harriet Ross\, the regulatory director. \nPascal\, good afternoon. \nI’m Pascal Samoy and I work in dredging and sediment \nmanagement. \nAnd then Jaime\, looks like you are also here. \nYeah. \nHi everybody. \nI’m Jaime and I’m also working with the sediment team here. \nGreat. \nAnd then Kat\, of course. \nHi\, I’m Kat. \nI support the sediment team. \nI’m also running the Zoom today\, so if you have any technical \ndifficulties\, please feel free to message me. \nYeah\, and Kat is our main communicator on a lot of these \nthings\, so if you see emails from Kat on this subject\, please \nopen them. \nOK\, so everyone else\, if you can put your name and affiliation in \nthe chat as a way of saying hello to your colleagues\, that \nwould be great. \nI’m sure we’ll hear from many of you during the meeting today. \nWe have a couple of independent science panel members here with \nus and some members of the S TAC\, the SANTAC Technical \nAdvisory Committee. \nWe have the Sand Miners industry representative as well as \nmembers of the public. \nOh\, and I also missed Mark Zapatella\, who’s with BCDC. \nSorry\, Mark. \nYou’re on mute\, my friend. \nOK. \nHe’s Mark Zapatello. \nHe is one of our legal counsel emeritus and still working with \nus at BCDC. \nThank you\, Mark\, for being here. \nOK\, so there’s there’s a problem with the link I can’t get on. \nIt says another meeting’s under progress\, and that is our friend \nJim McGrath. \nTry leaving the meeting and rejoining. \nJim. \nI’ve done that. \nOh\, I will. \nKat\, can you e-mail? \nDo you have Jim’s e-mail? \nYes. \nYeah\, But you are currently in the meeting\, so I think it looks \nlike you’re here on our end. \nYeah\, I’m. \nI’m there on phone\, but I can’t get on on the Zoom call. \nOK\, I’ll reach out to you. \nYeah. \nHang tight\, Jim. \nWe’ll see if we can get you into the actual meeting. \nThank you. \nAnybody else having problems? \nNo. \nOK\, OK\, So just I’m gonna briefly give a presentation at \nthe moment to kind of set the context for this commissioner \nworking group and for the public\, because I recognize that \nnot everybody came to the last commissioner’s Commission \nmeeting where we did present briefly on what our plan is \nhere. \nBut this commissioner working group is to dig into the science \nand understand what we’ve learned over the last three to \nfive years and give the opportunity for the \ncommissioners and the public to kind of catch up with the \ndifferent studies and hear more in depth from the scientist and \nthe Independent Science panel what they did to find this \ninformation\, What it what implications it has for the Bay \nsand system and also potentially for sand mining in the future. \nWe anticipate having permit applications for additional sand \nmining in 20 end of 2024 through 2025. \nTheir state lands is on the phone and they’re doing a sequel \ndocument currently for the same. \nSo we’re trying to make sure everybody has an opportunity to \nreally learn about this new and very interesting science. \nWhat this is not\, this is not a meeting about permitting. \nIt is not a meeting where we’re really focusing on the mining \nactivity itself\, but really the studies to make sure that we’re \nall on the same same page to the best of our ability. \nSo if you do have questions or thoughts about these different \nkinds of science that’s been done\, we do encourage folks to \nask questions because we want everybody to feel like they \nunderstand. \nWell. \nAnd so with that\, I’m going to start with my presentation. \nAnd I also I’m having a little bit of an allergy attack today. \nSo if I’m a little foggy or scratchy\, I apologize\, but let \nme go ahead and share my screen. \nLet’s see. \nCome on baby\, let’s share the screen. \nOK? \nAnd should be there 1 moment. \nWe’ll get into presenter mode. \nMaybe we will\, maybe we won’t. \nOK\, and now I can’t see you. \nSo Kat\, if you can work for hands for me\, that’d be really \nhelpful. \nSo I oh\, this is anyways\, I’m going to share the screen. \nWe’ll just excuse the notes. \nSo sediment program manager for BCDC\, basically there’s a bit of \na project history here on sand mining. \nSo mining has occurred in San Francisco Bay at least back to \nthe 1930’s. \nThe BCDC has records on sand mining back through the 1970s. \nBCDC was created in 1965 S Prior to that we really didn’t have \nany permitting or reports in on what type of mining was taking \nplace or where. \nIn the early days of sand mining\, prior to the 1990s\, \nthere were multiple small sand mining companies throughout the \nsandy areas of San Francisco Bay. \nIn the 90s\, they were consolidated into three \ncompanies. \nSo Martin Marionetta at that time was Hanson Aggregates. \nThey consolidated most of the lease areas in the central San \nFrancisco Bay. \nLind Marine was Morris Tug and Bard’s\, also Jericho products\, \nbut they have taken over or changed names. \nReincorporated\, not sure exactly which Bill can clarify\, but they \nare mining primarily in Sassoon and then Sassoon Associates is a \njoint venture of the two companies. \nThroughout the history where we have documentation from reports \nof sand mining from the miners themselves through the 19 four \nfrom the nineteen\, 1974 through 2023. \nThis is basically a histogram of all of the mining that we have \ndocumentation of. \nThere was some mining off of lease areas that wasn’t \nreported\, so this may not be all of it\, but this is generally \nwhat we have in the reported record. \nAnd you can see that the highest level of mining took place in \nthe early 2000s\, which is primarily the.com years\, where \nthere was a very large amount of construction going on in and \naround San Francisco Bay. \nIt dipped very significantly in the mid 2000s due to the Great \nRecession and the change in construction happening. \nBut also as we’ve noted at other times\, there was permitting \ngoing on between 2000 and two\, 2013 and 2015 that there was \nsome related reduction as those permits were getting close to \nexpiring. \nAnd then you see the sand mining coming up again through 2018 and \nstarting to drop off again in the last few years. \nIt’s really important to note that sand is mined in San \nFrancisco Bay primarily for construction and so construction \naggregates. \nSo you see a trend that follows the construction industry \nbecause that’s what this material is used for. \nIn 2013\, the miners requested 2.2 million cubic yards of \nmining total from the different agencies and they submitted 4 \napplications\, one from Central Bay\, one for Sassoon Bay Channel \nwhich is the Sassoon Associates\, one at Middle Ground Shoal by \nLind Marine and one at Middle Ground Shoal for Martin \nMarionetta and the request for his 410 year permits. \nIn 2015\, the Commission along with the Water Board\, State \nLands Commission\, the Army Corps of Engineers all issued permits \nfor sand mining. \nBCDC and the Army Corps permits are the most aligned because \nBCDC acted third in the in the ranking of the permits being \nissued in the Army Corps acted after BCDC. \nSo we worked very hard with the minors over a three-year and \nnegotiated a reduction in volume\, but the reduction in \nvolume\, so it came out to 1.42 million total throughout the \nregion. \nBut there is an allowance within BCD CS permit that if the miners \ndo not mine their total amount in any given given year\, they \ncan do additional mining within that volume in the following \nyear. \nThat has not occurred. \nWe issued the Commission issued 3 permits\, one for Central Bay \nto mark Marionetta at 1.14 million\, one to Sassoon \nAssociates for 185\,000 cubic yards and the last to Lend \nMarine at 100\,000 cubic yards. \nYou know\, you’ll note that the one for Martin Marionetta for \nMiddle Grand Shoal was not issued because that permit was \nwithdrawn. \nThere was application was withdrawn. \nThere was no mining that had taken place on Middle Grand \nShoal for over 10 years. \nAnd so it was determined that that lease\, a permit was not \nnecessary. \nThe issues the permits were issued for 10 years as \nrequested. \nThey required studies which included water quality \nmonitoring to make sure there wasn’t an impact to the water \nquality from mining\, a benthic habitat study and the studies \nthat are subject of this Commissioner working group\, \nwhich is the sand transport sand budget and the potential impacts \nof mining to the sand system within the Bay. \nThe miners contributed $1.2 million towards these studies\, \nwhich is a remarkable amount and really did allow for us to do \nthis\, pardon the pun\, deep dive into the sand transport and \nbudget within the region. \nThe permits did require mitigation\, which included \nremoval of a specific amount of Bay fill to make up for impacts \nto the subtitle area\, but also to address essential fish \nhabitat issues with NOAA Fisheries installation and use \nof fish screens on the intake\, water intake lines to the system \nand a reduction in volume at 2. \nTwo of the lease sites. \nAnd I’ll speak to that in just a minute. \nSo the Central Bay lease areas are these and there’s basically \n4 leases\, but there’s nine parcels. \nSo some of the parcels\, if you look closely you’ll your screen\, \nyou will see that some say for example\, seven O 9 N and there’s \nanother which is seven O 9 S. \nSome parcels make up one lease 3 parcels will make up one lease \narea. \nFor example\, this area is deeper than the other two areas. \nAnd the mining here takes place in depths up to 90 feet. \nThis area right here\, this triangle piece. \nI think you guys can see my my arrow is considered raccoon \nstraight. \nThere is no mining that takes place in this area. \nI think that it’s probably too deep and too swift to actually \nhave mining activities taking place. \nThese are all state lands Commission leases and there’s \ntwo types of sand that are mined in this vicinity. \nThe coarse grain sand which you see on the left of the screen\, \nthat is coarser grain material which is often used in concrete\, \nand this finer grain sand which comes primarily from the \nPresidio Shoal area\, which is used more for backfilling of \ntrenches and other uses. \nWhen you break down that overarching graphic of the \nmining that’s taken place over time\, this shows what’s happened \nsince 2000. \nSo different time frame\, but 2000 to 2000. \nOh\, I’m sorry\, the numbers are wrong. \nNo\, the numbers are right\, 2000. \nSo the last 20 years of mining\, which is the most relevant. \nAt this point\, 2000 to 2023. \nAlso notice on the Y axis that the scale changes in the next \nthree graphs that I’ll show you\, but at 1.4 million is about the \nmaximum shown on this graph. \nAnd you can see the difference over time in that mining trend \nfor Central San Francisco Bay. \nAnd again\, the maximum allowed for mining here is 1.4 million \nas of 2015\, which is about here. \nI put it. \nProbably should have put a dash line on there for you. \nMoving over to Sassoon Channel\, the primary area that’s mined in \nthis area in this lease is here. \nIt’s also important to note that BCDC does not have jurisdiction \nover this part of the lease area. \nSo we would not have reports on this\, but I don’t believe mining \nis occurring in this area. \nSo in this area\, that’s a little shallower mine\, mining happens \nin two depths of up to 45 feet. \nThese are again a lease by State lands made-up of two parcels and \nthis is primarily fine grain sand. \nAnd here’s the histogram for this and notice again\, 22\,000 to \n2023. \nthe Y axis now is gosh is a little different. \nBut what we’re seeing here is the trend changing. \nSo this low point during the the permitting. \nAnd I think this lease was almost out of volume during the \npermitting. \nBut then it ticked up again. \nAnd you’ll notice that this is higher than it is at Sassoon. \nYou’ll I mean middle ground. \nYou’ll see middle ground has dropped off quite a bit. \nAnd the reason for this is not only are they the same kind of \nsand\, there’s more volume authorized on this permit \n185\,000 per year\, but also because middle ground Shoal\, \nit’s shallower and considered potentially a more sensitive \nhabitat\, the agencies adjusted the volumes to be more volume \navailable to be mined and Sassoon channel versus middle \nground Shoal. \nSo here’s middle ground Shoal and this this smaller lease \narea\, I always think it looks a little bit like a bird head. \nOne of the important things to note about this lease is that \nwhile it’s a large lease area\, you know when you look at it \nvisually\, the mining really only happens in the southern portion \nof the lease because part of it is actually intertidal or even \nsuper tidal. \nSo the area that’s deep enough for the miners to mine is this \nsoutherly portion. \nSo in this area I think we have up to 30 feet deep\, but actually \nmuch shallower in some locations. \nIt’s an adjacent to an island. \nThis graphic doesn’t show the island\, but it’s right here. \nThis is a privately held lease\, not part of State Lands leasing\, \nbut State Lands has analyzed it as part of the Sequa NEPA\, the \nSequa document. \nAnd then again\, it’s that fine grain sand very similar to \nSassoon channel. \nAnd here you see the permitting 2015 and the significant \nreduction in the mining volume at middle ground less than \n50\,000 in the last several years. \nAnd a lot of that is due to the pushing the operation more to \nSassoon associates to deal with this potential effect to that \nshallower habitat which has potential to be spawning grounds \nfor smelt. \nSo briefly moving on to the mining equipment. \nThere are two sets of mining equipment\, Lindh Marines. \nTheir barge holds about 1400 cubic yards of sand and Martin \nMarionetta is more closer to 2100 cubic yards of sand. \nJust gonna quickly run through this. \nThe sand is pumped up onto the the mining equipment through a \ndrag head. \nThis is Hanson’s equipment. \nThis is the drag head. \nIt has a fish screen on it to reduce entrainment of fish from \nthe water being pulled in. \nThe sand is pumped across the chute running down the middle of \nthe barge and sand is self sorted and comes off over the \nside of the chute into the barge and area and sand that is too \nlarge or larger pieces is is pushed off the barge back into \nthe Bay. \nHere is a close up of the Martin Marionetta barge or equipment. \nSo here’s the hydraulic head again with the fish screen right \nthere mounted on the pump coming on board. \nHere’s the drag head with the grid across the bottom. \nThese are approximately 6 inches by 6 inches\, which helps keep \nlarge items out of the drag head. \nThis drag head is put 18 to 3 feet into the sand. \nThis is Lynn’s suction pipe. \nSo this is more of a stationary dredge where the pipe is \ninserted down into the sand. \nHere’s the fish screen. \nAnd I always think of this more as kind of like if you’re \ndrinking a chocolate malt and you drink with a straw\, the the \nsand kind of goes in like your chocolate malt into that straw. \nVersus this is a little bit more like a vacuum cleaner being \ndragged until it hits this type of sand that’s desired. \nAnd then the barge does stay stationary for a period of time \nto collect that sand. \nSo some quick notes about the the mining activities for those \nof you who are really familiar with navigation dredging\, I just \nwant to note a few differences. \nSo mining here again is for construction aggregate. \nIt’s not for navigation\, although Sassoon channel \ndredging or mining does happen adjacent to and I believe \npartially within the federal navigation channel. \nThat’s not normally dredged for navigation\, but it is within a \nfederal navigation channel. \nIt’s not generally considered beneficial reuse under the LTMS \nlexicon because it’s not a waste product being reused as disposal \nof dredge sediment is\, but in fact a resource being mined for \nits specific use. \nDifferent than navigation dredging mining occurs year \nround. \nThere’s no work windows for sand mining\, but there are fish \nscreens on the intake pumps to reduce impact to listed species \nand that was per biological pinions from Noaa’s Fisheries \nand US Fish and Wildlife Service with an incidental take permit \nfrom California Department of Fish and Wildlife. \nThe mining location is based on the leases and the mining \nactivity is based on the grain size of sand desired. \nAnd again\, as I mentioned earlier\, Central Bay is \nprimarily coarse grain sand with some fine grain and certain \nShoals and it’s most appropriate for use in concrete and asphalt. \nAnd then Sassoon and middle ground are fine grain and \nappropriate mostly for trench filling and other uses. \nAnd then mining doesn’t occur to like a specific depth or area \nlike navigation drudging does. \nBut the mining does occur often and regularly in the same area \nbecause of the the selection of the grain size that is located \nin the lease areas in those areas based on sand transport \nand the sand system and what is is bound where to make it \nsimple\, just a quick couple of quick slides from some of the \nstudies which you’ll hear more about I think another day. \nBut you can see here’s 1997 version looking at some \nbathymetry. \nAnd this is the area that was examined for one portion of the \nstudy. \nAnd what you see here in the same area is a bed lowering. \nAnd this is point knock Shoal by 2019. \nAnother quick look\, here’s another example in 1997. \nHere’s your examined area 3. \nAnd then here’s the examined area again\, bed lowering and \nShoal disappearance was the result of one of the bathymetric \nchange analysis. \nBut it is important to note that as I said in the previous slide\, \nsand tends to sand mining tends to occur in the same area \nrepeatedly. \nAnd so you would expect to see these localized\, excuse me\, \neffects where that grain size can be found. \nI think I’m almost done here. \nSo on our study process\, just real quickly switching gears\, \nthe funds were provided that $1.2 million. \nWe have the SAN technical advisory committee who developed \nmanagement questions\, study scopes\, worked on a request for \nproposals and reviewed proposals. \nAnd then our independent science panel members who reviewed the \nproposals\, reviewed revised scopes\, worked with the teams to \nreally hone their study development and then reviewed \nthe completed studies and the findings and they developed the \nfindings report with Santech who wrote the report with them. \nThe questions that the I just put the questions up for this \nfrom the Sand Technical Advisory Committee\, which was the main \nfocus of these studies. \nSo is sand mine\, is sand mining in existing areas at permitted \nlevel\, permitted levels having measurable or demonstratable \nimpact on sediment transport or supply within San Francisco Bay? \nThere’s a question which is what’s a sustainable number\, \nwhich I believe is about sustainable number of mining and \nwhat is substantial depletion considered. \nThe second main question that was asked is what are the \nanticipated physical effects of sand mining at the permitted \nlevels on sand transport and and supply within San Francisco Bay \nand the outer coast? \nWhat is the impacts to active sands and the consequences to \nbeaches and tides that it feeds? \nWhat’s the impact to relic sand\, which is how much is the volume \nand where is it? \nAnd are there other feasible sand mining approaches to \nconsider in San Francisco Bay? \nAnd should there be a modification of a volume and \nsite and site and conditions\, sort of a three Fer question. \nSo the folks who’ve been involved for the last several \nyears\, which I will be eternally grateful to because this has \nbeen taking a village and a lot of people’s really good strong \nthinking on this work. \nThe state Coastal Conservancy managed the studies and tracks \nand the funds\, which I can’t ever thank them enough. \nBCDC was a member of the SANTAC and worked with the Coastal \nConservancy to keep the process on track. \nThe Coastal Commission\, State Lands\, Army Corps\, Water Board\, \nNational Marine\, Fisheries\, Cal. \nDepartment of Fish and Wildlife\, Bay Keeper Martin Marinetta and \nand Marine. \nWe’re all members of the technical advisory committee\, \nthe Independent Science Panel. \nWe have a couple of the members here today who will present \nnext\, which included Bob Battaglio from Environmental \nSciences\, Craig Jones from Integral\, Jean Lazier from UC \nDavis\, Dave Schulhammer\, USGS\, and Paul Work from USGS. \nSo great group of folks doing some really good thinking here. \nAnd lastly\, our research teams\, I’m not gonna read all the \nnames\, but there are three majors\, the sand budget\, supply \nand morphological chain and transport analysis. \nBig team there from actually international team. \nSo you can see the organizations that were involved with that \none\, the sand transport modeling and the sand Providence work. \nWe have sand Providence where Zach is here today\, as is \nMatthew. \nAnd they’ll talk to you today about that project or that \nstudy. \nAnd I’m gonna stop pretty much there because Next up after me \nis the independent science panel members introducing their key \nfindings. \nAnd with that\, I’m gonna stop sharing my screen. \nThat was a quick\, quick\, quick tour. \nWell\, thanks\, Brenda. \nHey\, this is Bob Vitaglio. \nI’m one of the ISP members that I think are up next\, and we’re \ngonna try to move fast. \nHey\, Dave Schulhamer\, are you online? \nAm I supposed to share the presentation or are you? \nAnd while you’re working on that\, what’s that? \nI’m sorry\, we’re working on that. \nI’ll share it. \nOK\, Pat\, go ahead. \nCommissioners\, do you have any questions or any items that you \nwanted to ask while I ran through that very quickly\, I \nknow you saw a version of it a couple of weeks ago. \nBrenda\, I do have one question. \nI\, I’ve been reading the\, the briefing documents you sent our \nway and one of those key\, and maybe this is maybe this is \nsomething that Bob’s gonna get to. \nBut that briefing document you talked about rates of \nreplenishment\, but it didn’t have time frames for that \nreplenishment. \nAnd you\, your some of your slides kind of got to that. \nBut I was just trying to get a handle on what the annual \nreplenishment rates were and I didn’t get that from all the \nparts of that document. \nSo if we’re gonna get to that later\, fine. \nBut I thought I’d throw that question out now. \nYeah\, I think the answer is it is variable depending on the \ndifferent locations. \nAnd that will be the subject of another meeting when we bring \nsome other folks in. \nAlthough I don’t know if Bob or Dave\, you want to respond to \nthat at this point. \nI’m sorry. \nI was trying to figure out how to load my presentation. \nSo I missed the question. \nI\, I\, I think Dave is\, was probably listening and Kat\, I’m \ngoing to need help becoming presenter. \nI don’t\, I don’t think I can do that on my end. \nI think I’m not in control. \nIf\, if you look at the bottom and see share screen\, it’s a \nlittle green box. \nThat’s\, that’s all you have to do. \nOK\, starting off very embarrassing. \nNow you’ll know why we don’t know which way the sand’s \nmoving. \nI\, I\, I was\, I just had a quick question about really the \ndifference between fine sand and coarse sand. \nHow and\, and generally not\, not just obviously there’s a size \ndifference\, but in terms of the deposit\, the the deposit size\, I \nwould just assume that there’s a lot more fine sand and there is \ncoarse sand. \nBut I just wondered about that. \nYeah\, I\, I don’t know if you want us to jump in and I\, Barry\, \nI’m sorry\, I didn’t catch your question\, but I think that’s \nright\, Pat\, that\, that we have more of the finer sands. \nThe beach sands are kind of in the middle between the two \nimages that Brenda showed\, which I really appreciate. \nIt’s it’s nice to see those pictures. \nBrenda\, we\, you showed a know if you wanna show it again\, the\, \nthe coarse and the fine. \nBut\, you know\, the course is really old. \nI think the that really coarser stuff. \nI I don’t think it’s moving that much through the Golden Gate. \nThat’s my opinion anyway. \nBeach sands are smaller than that. \nYeah\, I’m not gonna show it again right now. \nI can pull it up again later. \nI see Dave’s got his hand up. \nAnd also if the miners want to answer that question from their \nperspective too\, I think that’s also welcome. \nYeah\, Dave\, I was going to go back to Barry’s question about \nthe recovery rates. \nThey’re expressed\, I believe\, as in a percentage of recovery\, \nessentially how much of the remove sand is returned during \nthe period of time between where we had the bathymetric surveys. \nBasically\, I think this was done just because there’s sort of \naveraging over that period. \nNow those numbers could go back to the raw data the \ninvestigators had and come up with an actual number of\, you \nknow\, cubic yards per year on average of going back into the \nmining area for each of the lease areas\, I believe and the \nway the day is presented\, but I don’t recall it being in the \nreport\, but the results could be presented that way. \nI think we were looking more at the percentages\, the rates of \nrecovery as relative to how much is coming in and how much is \ngoing out to compare it that way. \nYeah. \nAnd I will also just add for reference that we have I think 5 \ndepending on the lease area\, 5 Series of bathymetric surveys. \nSo we started\, maybe there’s only four\, we started requiring \nthem in 2004 and they’re required every five years. \nSo we have a series of five year surveys and then we did one \nsurvey between 19 or excuse me\, 2018 and 2019 because we have \nthis really interesting water year while we were working. \nI think that was the right time frame where we did one in a very \nspecific set of bethematry to do a quick analysis at the request \nof the independent science panel. \nI want to make sure that the miners also have an opportunity \nto ask questions. \nSo are there any questions at this point from from the minors? \nI will just I will just this is Eric Aguera with Marty Marietta. \nAnd I will just act a little bit of as a moderator because we \nhave a big group here and I think it would be good if we \nhave Mike Bishop from Marty Marietta basically expanding a \nlittle bit more on your question on the grain size and what we \nuse that sand for. \nSo Mike\, hi everybody. \nSo\, yeah\, so the fine sand is is typically mined off Presidio \nShoals on the South side of the Bay. \nAnd as Brenda said\, it’s\, it’s typically used in foundation and \ntrench backfill. \nIt’s a very\, it’s a very uniform sized sand. \nAnd and I I describe it as soft and on the north side of the \nBay\, which is point NOx etcetera is there is\, is our coarse sand \nwhich predominantly as Brenda said goes into into concrete. \nYou know\, there there the the difference in size is really on \nthe top end of of the sand fraction and on the on the \nbottom end\, which is what you know would be silts and and fine \nsediment. \nNeither neither\, neither sand has much of that. \nYou know\, we measure it on\, on graduation sieves and the 100 \nmesh is\, is still a fairly large Staley fairly large sieve at at \n70 microns\, 75 microns\, something like that. \nAnd you know the the these two sand deposits just don’t have \nthat really fine fraction that is silts and which\, which \ngenerally is\, is is dredged in maintenance dredging. \nYeah\, the two sands are quite different if if just to the \nnaked eye and hopefully that will answer your question. \nYeah. \nSo it sounds like what you’re saying is that the\, as somebody \nmentioned earlier\, the\, the\, the sands\, the fine sands that \nyou’re\, you’re mining are very well sorted so that they’re \nalready ready for a specific use in construction ’cause I know \nyou use different\, I don’t know too much about this\, but I do \nremember that you use\, you use different grain size for \ndifferent uses and sorting sands into different grain sizes is\, \nis expensive. \nSo\, so I get the impression from what you’re saying that that \nthese\, these are sort of pre sorted\, these are very well \nsorted. \nSo that’s\, you know\, that makes them valuable. \nIs that\, do I get that right? \nThat is that is very correct. \nMother Nature does a great job at at sorting out this sand and \nthe coarse sand basically is a is comes out at a concrete \nspecked sand. \nWe have to do very little of it processing onshore and and \nfundamentally really onshore. \nAll we do is is give it a bit of a wash with some fresh water to \ntry and lower the salt content. \nOf the sea water that we mine it out of. \nBut you know\, and and that really lends itself to where we \nmine is physically where the currents etcetera allows this \nsand to drop out and or to have dropped out in the past. \nSo you know\, there\, there is particularly with the coarser \ngrain which is the concrete sand\, which is\, is\, is the \nhigher demand of sand is is very specific where we where we can \nget that sand from. \nWe can’t get it from just anywhere in the Bay. \nYeah\, no\, OK\, thank you. \nYou know that does that’s a great answer. \nI appreciate it. \nAny are there any other questions? \nI’m kind of looking for hands raised and not seeing them. \nI I think Ben Butler from the Marine. \nYeah. \nAnd we’re about 10 minutes behind schedule now. \nSo\, Bill\, if you can be brief\, please. \nOh\, OK. \nSorry\, Rinda. \nHave I ever been anything but brief? \nYeah. \nSo thanks. \nBill Butler with Lynn Marine. \nSo thanks\, Mike\, for your description on the sands. \nI would just also like to add as far as uses are concerned\, the \nthe fine sands while while they are indeed a little smaller size \non the top of them\, they’re still very clean as Mike \nindicated and used not only just for backfill\, but our stands \nthat we mined out of the Sassoon area are used quite extensively \nin\, in asphalt. \nIt’s\, I think it’s just also important to point out too that\, \nyou know\, not not all sand is\, is the same. \nFor example\, this isn’t like beach sand that we’re mining. \nWhen you go to the beach and you see\, see sand like that\, that’s\, \nthat’s very different than than this sand. \nOur sand contains a range of sizes that\, that make it \nvaluable for construction as well as being\, you know\, \ndurable\, durable and and fairly clean. \nSo I just wanted to make that distinction as well. \nThank you. \nOK. \nAnd I see Richard Gunther has a question. \nThanks. \nDo we know how much sand in these different categories is \nused in the Bay Area? \nCommissioner Gunther\, I’m going to have to ask you to hold on \nthat question because this is really about the science and \nwe’re behind and I would like us to continue and not get into the \nuse of the sand right now if we can\, please. \nOK\, that sounds good. \nWhy don’t you keep going? \nSo who’s next? \nI would like to introduce Dave Schulhammer and Bob Battaglio. \nOK\, I think that’s my prompt. \nIf it’s OK\, then I will push the green button and share my \npresentation. \nYes. \nOK. \nHopefully I can do this. \nThis is kind of OK. \nWhere’s my presentation? \nHere it is. \nLet me go back to the first slide and you’re all set. \nThere we go. \nOK\, OK. \nAnd so as Bob and I agreed to a few minutes ago\, I will start \noff here. \nThis is Dave Schollhammer of the Independent Science Panel and \nI’ll take care of the first few slides. \nBasically\, my role here is to be the warm up act for Bob. \nWe’ll finish up the presentation. \nSo on the next slide\, Bob\, the Independent Science Panel is \ncomposed of five of us\, myself\, Bob\, who is a expert in coastal \nsediment transport and has been working in San Francisco Bay for \na long time\, as have really all of us. \nCraig Jones\, another coastal engineer\, has done quite a bit \nof work over the decades with sediment transport and some \nmodeling work. \nJohn Largier at UC Davis\, who’s really the\, the\, the expert at \nwhat’s going on\, especially at\, at\, at the Golden Gate myself\, \nmy background has primarily been studying fine sediment transport \nthe the finer material\, but with some sand thrown in. \nAnd finally\, Paul Work\, another coastal engineer with the \nformerly with the Geological Survey\, who also has spent\, \nspent a career studying sand transport. \nSo we are the members of the Independent Science Panel who \nall contributed to developing the studies. \nWe’ll be talking about and writing the summary report that \nBob will be talking about on the next slide. \nBob\, we have the list of the studies that’s already been \nmentioned and we’re gonna go through these briefly. \nSo this is sort of an outline of the rest of what you’re going to \nhear from us. \nThe SAN budget study and modeling studies. \nI will explain and then Bob will very briefly mention the \nfingerprinting study cause Zach and Matt are here to describe \nthat study in more detail. \nAlso with these studies\, the USGS provided a tremendous \namount of support in various ways to all three of these \nstudies and Deltares also provided some support through \nsome analysis that they did for different parts of these studies \nalso sort of as subcontractors. \nOnce these studies were completed\, we\, the ISP\, wrote a \nsummary report that described the studies briefly and tried to \nsort of do a sort of a synopsis of the studies and what we felt \nit meant in terms of some overall findings on the data \ngaps we observed and some suggestions for the next steps. \nSo those are the list of the studies. \nI’ll start in next on the SAN budget presentation. \nThink you need to click something else there\, Bob? \nThere you go\, one more OK\, it’s right back one OK. \nSo for the sand budget\, this was largely to address the first \nmanagement question that Brenda had mentioned about is the sand \nmining having a measurable or demonstrable impact on the \nsediment transport and supply within the Bay. \nThis was primarily done by the San Francisco Estuary Institute \nwith Lester McKee as the lead\, though as was previously shown\, \na number of people helped with this study and also the USGS and \nDeltares. \nOn the next slide\, one more Bob\, we have the show a picture of \nwhat the basic components of a sand budget and that we take a \nvolume of the Bay or you can think of this as a bubble. \nEngineers give it a fancy word\, a control volume\, and we look at \neverything\, all of the sand that flows into that volume and all \nthe sand that flows out of that volume. \nAnd with the principle of conservation of mass\, we can’t \ncreate mass out of thin air. \nWe know that the change in the storage of sand on the bed must \nequal the inflow minus the outflow. \nSo this is the basic idea of a sand budget and how we can \naccount for all the factors affecting sand transport and \nsand supply. \nOne note is on the bottom here. \nThis equation is based on conservation of mass. \nLater we’ll be talking some about uncertainty\, but there is \nno uncertainty in this equation. \nYou know\, mass must be conserved and this equation essentially \nexpresses that. \nOK. \nBob on the next slide\, one more please. \nFor doing the sand budget\, generally speaking\, we have \nability to quantify what the inflows that they are through \nthe tributaries as the VI did a tributary watershed modeling for \nthis. \nAnd we can also quantify other outflows. \nFor instance\, the sand mining is an out in this sand budgeting\, a \nsand mining is an outflow and we can also quantify the change in \nthe storage with the that bathymetry work that the USGS \ndid to look at the change in bathymetry over time generally. \nWell\, in all cases for our work here\, what we don’t know is the \noutflow of sand toward the ocean. \nSo we can take the equation I showed previously and rearrange \nit to actually be able to solve that equation for what the \noutflow toward the ocean is. \nSo what Sfei and others did is they estimated what all the \nvalues of the inflows were\, what all the other outflows are\, and \nthen also estimated what the change in storage was to compute \nwhat the outflow toward the ocean is for San Francisco Bay \nand for some of the seven payments. \nAnd again\, I think the analogy here is on the an analogy would \nbe that this is very similar to being like a checking account. \nYou write checks\, you have an outflow\, you make deposits\, you \nhave an inflow and the balance in your checking account changes \nover time depending on the outflows and the inflows. \nSo on the next slide\, Bob\, one more I believe OK\, we have the \nsome some highlights from the budget. \nSo SFVI did this for all the major sub embayments in the Bay \nand for the entire Bay. \nWhat I’m showing here is the sand budget for Central Bay that \nshows all of the inflows that were determined and the \noutflows\, the change in storage\, all to essentially balance the \nsand budget for Central Bay. \nAnd they looked at various things\, some of which are very \ninsignificant and some of which are very significant as shown by \nthe size of the arrows. \nWhat they found was that the San mining was a essentially a very \nlarge term that does in fact\, in fact the budget. \nAnd in fact here in this particular case it’s the largest \nterm hit the one more push Bob\, I believe another question that \nwe frequently had was the sand transport out at the Golden \nGate. \nThat is what we would call an uncertain number. \nThe sand budget came up with a value of .25 million metric tons \nper year\, which is about 200\,000 cubic yards per year of outflow. \nBut there are there is uncertainty and one of the ways \nthat as if I evaluated that uncertainty is they took all the \ninflows and outflows and the change in storage that they did \ncalculate for each of those. \nThey have a range of what the possible numbers could be. \nAnd they took those then and sort of set them to their \nmaximum or minimum possible values to see what the biggest \npossible inflow to the Bay is\, what the biggest possible \noutflow to the Bay of Sand is. \nAnd wound up with a range of .66 to in to 1.1 out of sand \ntransport at the Golden Gate with the best value being .25 \nmillion metric tons per year. \nSo that’s one way of evaluating the uncertainty is we know these \nnumbers\, assuming they won’t be pegged to their minimum or \nmaximum values will be between somewhere between the .66 and \nthe in and the 1.1 number out. \nAnd the best estimate there is .25 out. \nSo that’s one of the one of the results of the sand budget \nagain\, it’s you know 100 page report with lots of results \npacked in there. \nLet’s go on Bob to the next slide. \nAnd I think that’s it. \nSo the numerical modeling study\, the second of the major studies \nthat was supported in this effort. \nGo ahead and click once more. \nBob actually addressed that first management question about \nthe demonstrable impact on sediment transfer in the Bay and \nit also looked at at at addressed the second management \nquestion about the anticipated physical effects of sand mining \nwithin the Bay. \nThis study was done by Anchor QAA\, Michael McWilliams and \nAaron Beaver and were the folks doing the modeling here. \nSo let’s move on to the next slide\, next one\, and click a \ncouple more times to fill up the right side text. \nThe numerical model they used is called the untrimmed model. \nThis is again his numerical computer model. \nIt’s a 3 dimensional model\, so it covers what you see here and \nthe depth within the Bay. \nIt models the tides\, wind\, waves\, salinity. \nFor the sediment modeling\, they use 4 grain sizes. \nThe tributary inflows that SFDI calculated for the sand budget \nwere used in this model so that they’re comparable results. \nThe model has previously been calibrated by Aaron and Michael \nto water level\, salinity and suspended sediments. \nI know Craig Jones\, one of the ISP members\, told the RMP \nrecently that he thought this was the\, he’s actually \ndeveloping a contaminant model for the RMP and he thought this \nwas one of the best models for San Francisco Bay. \nWhat Aaron and Michael did to look at the effects of sand \nmining is they simulated low and high flow years where there’s \neither a little or a lot of freshwater flow into the Bay and \nthey simulated them with and without sand mining. \nEssentially\, the sand mining was a term removing sand from the \nlease areas as the information from BCDC on those rates. \nAnd they simulated the Bay with and without the sand mining to \nbe able to compare those results\, take the difference and \nsee what the effect of the sand mining was. \nOK\, So the next slide\, Bob\, we have some highlights here. \nOne is that the net sand transport at the Golden Gate was \ntoward the ocean at about 80\,000 cubic yards per year\, which was \na little less than what the budget came up with\, if you \nrecall\, about 200\,000 cubic yards per year. \nNow we have a number of 80\,000 and 200\,000 in the\, you know\, \nstudying sediment. \nThere’s a lot of uncertainty looking at sediment transport \nthat as scientists we get used to. \nThese numbers actually I’d say in the segment world are fairly \nclose. \nThe joke we would have in the science circles was if you \nagreed within a factor of 2\, you should go publish a journal \narticle about it because that’s good agreement. \nSo that was one of the highlights here. \nAnother on the second bullet is that up in Sassoon Bay they \nmodeled these for one year and the effects of sand mining \nthrough the Bay were really limited to the vicinity of the \nmining areas. \nIn other words\, it the effect of the mining dispersed very \nrapidly with distance from the mined area up in Sassoon Bay and \nit was somewhat true also with Central Bay. \nOver down in Central Bay\, they found that the total transport \nof sand out of the Golden Gate\, they predict a decrease by 59 \nand 32% because of the sand mining during the high outflow \nand low outflow years was one of the numerical modeling results \nthat they came up with. \nSo those are just some of the highlights from the numerical \nmodeling study. \nAgain\, it’s a very lengthy detail. \nI think that was a 200 page study with all the figures that \nhas a lot more results in it that you can read up there. \nSo let’s go look at the next slide\, Bob. \nAnd here’s where I’ll turn it over to Bob. \nThanks\, Dave. \nAre there any objections for me to complete the presentation? \nDoes does anyone want to ask Dave questions about what he \njust said? \nWhile we’re at this pause\, I\, I\, yeah\, Barry Nelson here. \nJust one simple question where I’m not sure I successfully \nunderstood one of the lines. \nThere was a note there about .25 metric tons per year and \ntransport out the Golden Gate and that that translated to \n200\,000 cubic yards per year. \nI’m just trying to get the that that’s the slide and I’m just \ntrying to get those numbers to line up. \nThat’s not that\, that’s metric ton. \nWhat’s that’s £550 quarter of a metric ton\, 550 lbs or so. \nWell\, it’s actually the the capital M stands for a million \nthat OK. \nAnd\, but it is a metric ton and\, and the conversion we’re using \nis the one that SFEI used for sand deposits like those mined \nby the miners. \nThere were different conversions\, you know\, density \nconversions. \nI think the number is\, is right around 180 or maybe 160\,000. \nIt’s about 200\,000 cubic yards round numbers. \nI\, I\, I suspected that’s\, that was that I misread the M Thank \nyou. \nBob\, if I could ask one question\, this might be\, you \nknow\, the kind of somebody who knows just enough to be \ndangerous here. \nAnd we don’t only go down a rabbit hole\, but it’s my \nunderstanding that measuring net transport at the Golden Gate is \na really\, really difficult thing to do. \nNow\, I’m getting the impression from what you’re presenting that \nnet transport on the bed is not as difficult as net transport of \nthings that are floating back and forth with the tide. \nIt’s actually the opposite. \nThe the bed load transport is well\, I don’t know\, maybe I \nshould let was\, I would say the bed load transport is a bigger \nquestion mark. \nThe suspended transport you can get from you know\, taking \nsamples or doing kind of a remote sensing it. \nBut I guess aren’t we dealing with trying to\, we’re measuring \na huge number\, which is the transport in during any tidal \ncycle and then we’re trying to net out a very small number. \nYeah\, right. \nSo to your point\, the net is an estimate of the average over a \ntime period calculated as the difference between what’s \ncalculated one way added up and minus what’s calculated the \nother way added up. \nAnd so the net is small and less certain. \nYeah. \nSo if we go back into the last go\, just go forward this to the \nlast slide and then I just wanna then ask you about. \nYeah\, here we go. \nSo\, so at the top here\, we’re estimating this with one \nsignificant figure. \nAnd as Dave said\, you know\, hey\, that’s pretty close\, which I \nunderstand that. \nBut then when we say we’re talking about 59% and 32% in \ndifferent years\, I’m\, I\, I guess I’m trying to get a header at my \nheader on how we know\, know the numbers that accurately. \nI’ll let Dave answer that. \nThat was from the modeling and you know\, they’re precise \nanswers within uncertainty. \nSo\, but it it\, it does show that\, I mean that was the \nconclusion. \nWhether it’s 59% or 72% or 32% or 21 percent is is unknown. \nBut but this was the finding. \nBut Dave\, would you like to jump in on that? \nYeah\, as Bobby did an excellent job of answering that. \nThe last\, the 59 and 32% numbers are from the numerical modeling \nwhere all those bell that back and forth transport\, they can \nadd up and calculate a precise number. \nNow how accurate that is\, if it’s\, you know\, 70% or 40%\, you \nknow\, that could be argued and debated perhaps\, but they are \nable to calculate the more precise numbers with the \nnumerical modeling. \nIn terms of the transport of the gate\, remember that 200\,000 \ncubic yard per year number is basically taking the sum of \neverything else and moving it down to the Golden Gate because \nthat’s the number that’s actually being calculated by the \nsand budget. \nThere is no measurement showing 200\,000 cubic yards per year \ngoing out the Golden Gate or 80\,000 cubic yards per year \ngoing out the Golden Gate. \nThat’s the result of that equation I showed earlier of \ncalculating what that outflow is based on the inflows\, all of the \nother outflows and the change in bathymetry\, right? \nAnd so as long as you’re sure you\, you know\, all the sources \nof gain and loss\, then you get this is this number is derived. \nI\, I get that. \nSo\, so I guess what I’m just trying to get my head around\, \nDave\, is when\, and maybe this is just for going forward when we \nneed to be thinking about precision and when we need to be \nthinking about accuracy in\, in terms of understanding the \npolicy implications of these results. \nFor\, for the\, for the last thing here\, for the 59%\, the real \nquestion is not if it’s 59% or 55%\, but whether it’s 60% or \npoint O 6%. \nI mean that there’s\, there’s and\, and I’m just\, I guess I’m \njust still a little\, I’m not sure I have my head around\, \naround how well we know some of these things. \nAnd\, and\, and that’s the thing that I want to be. \nI\, I would really appreciate your help with. \nI mean\, if\, if the model produces a number that’s 60% and \nwe report that\, that’s fine. \nBut it’s\, there’s a lot of uncertainty in that number. \nAs I understand it. \nYes\, there is uncertainty in the\, you know\, quantification of \nthe inflows\, the quantification of the outflows\, the \nquantification of the change in the bathymetry and all of that \nkind of adds down to the uncertainty in the number going \nout\, say the Golden Gate. \nThe reports themselves detail those uncertainties since this \nis something we worry about a lot on the ISP about the \nuncertainties here. \nSo I think our summary report that Bob’s about to describe and \nthe individual reports that discuss the uncertainty delve \ninto the details of how well these numbers are known. \nGreat\, thank you. \nBecause it’s hard to answer\, give you a one off answer on \nthat very good question you’re asking. \nThank you. \nI will just add that the numbers that were included in the sand \nbudget on the navigation\, dredging\, in the sand mining \nnumbers were actual numbers reported for the last 20 years. \nAnd this this the sand budget exercise was from 2000 to 2020 \nwas the 20 years that were looked at and the dredging\, \nnavigation\, dredge mining data were actual reported numbers. \nSo there is some certainty in those numbers. \nWell\, there is pretty good certainty in those numbers and I \nsaw that there was another hand up. \nWe have time for one more quick question. \nMcGrath has a question. \nYeah\, it’s actually a a comment. \nFirst of all the the science I’ve I’ve read these reports and \nthe science is great. \nThere’s two other data sources that I\, I’d like to to give you \nthat\, that tend to support this. \nAnd I don’t know that the panels look at it. \nWhen I was at the Coastal Commission\, we regulated the \nCorps of Engineers dredging of the bar and\, and the bar had a a \nremarkably narrow band of grain size\, all about point 2.21 \nmillimeters. \nAnd our conclusion on that or our theory on that was at the \ndepth of the bar that was about the maximum grain size that \nwould be disturbed by the waves passing overhead using \nconventional wave theory. \nAnd\, and that’s the material I think that that moves around. \nAll of that data of course is available. \nSo that’s the first source that that tends to augment the \nquestions that were asked earlier about fine grained \nsediment and why it’s in the Presidio Shoal. \nThat’s what’s disturbed. \nThere’s an Eddy current. \nThere’s another source that we give you some insight into the \nrate of transport in that Eddy current. \nWhen the restoration efforts occurred at Crissy Field\, there \nwas no refilling of the inside bar and the outside bar. \nAnd over a period of I think it was five years\, about 35\,000 \ncubic yards of material collected there. \nSo that gives you some augmentation that you should \nprobably look at to\, to\, to give a\, some real measurement about \nwhat the the countercurrent was. \nSo I just thought I’d throw that out there before you got to \nprofits. \nThanks. \nThanks\, Jim\, really appreciate that. \nI\, I yes\, thank you. \nShould should I\, I’ve been thinking about this stuff for a \nwhile. \nYeah\, no\, I I really appreciate you being on the call too. \nActually\, that’s\, that was very helpful perspective. \nI have similar perspectives. \nShould I proceed? \nYeah\, I think you should. \nOK. \nThank you. \nNo\, that was a great discussion. \nI\, I\, I could have said some things\, but I’m going to move \non. \nWe can talk later if we have time. \nSo this is the\, the third study that Dave Schulhammer and I\, \nthis is Bob Battaglio of the ISP are presenting basically big \npicture. \nWe’re doing a brief summary of each of the SAN studies and then \nwe’re going to provide the independent science panels kind \nof distilled findings\, if you will briefly. \nSo this is just going over the fingerprinting study which is \ngonna be presented. \nI think I’ll just go through this quickly and then I think \nZach is gonna present their study\, which is is good because \nit’s a little complicated for a lot of us. \nBut basically the the fingerprinting study looked at \nmineralogy\, which gives you an idea of which mountain range the \nsediment came from. \nIt looks like at a component zircon\, which can be analyzed to \ntell you how old the deposit is\, which also can help you \nunderstand where it came from. \nAnd then there’s this thing called luminescence\, which is a \nreaction emanation\, if you will\, from the grains that the sand \ngrains that can be detected that tells you how long since it’s \nbeen it was daylighted subject to sunlight. \nI think I have that right. \nI’m sorry. \nI want to go back and just show you this image from the study. \nThe orange is coarser sand. \nThe the tan is medium sand and the\, the light tan is\, is finer \nsand. \nThe Gray is mud. \nSo you can see the sand mining’s up here around Sussoon Bay and \nthen down in Central Bay\, and you can kind of see where this \nis exposed\, where there’s strong hydraulics and out here waves \nand the like. \nThis little dotted line is the estimated shoreline of 14\,000 \nyears ago\, and then this line is around 10\,000 years ago. \nThe idea being that this was a river\, sea level rose and now \nit’s a drowned river. \nDelta’s way up here and this is the tidal exchange area. \nSecond slide of the fingerprinting study. \nManagement question Tier 21B. \nWhat is the source of mine sand in the lease areas? \nSussoon Bay deposited from local coast range drainages. \nCentral Bay eroded from outer Pacific Coast\, previously from \nSierran Range and coastal range. \nManagement Question Tier 21B. \nIs it relic sand or new sand transferred in the system? \nSand is relic. \nSome relic sand is exposed to hydraulic forcing. \nIt is in transit. \nSome relic sand is below the Bay floor and it’s not in transit. \nSo this is something that I think a lot of us could easily \nget stuck on. \nRelic means it’s not being supplied now\, but that doesn’t \nmean that it’s not moving around and it’s not being mined or\, or \nit is being mined. \nIt’s it’s relic and moving around and relic and not moving \naround. \nThis is a\, a conceptual model of\, of low sea level stand that \nI described before and you have the Central Valley rivers going \nthrough what is now the Bay and discharging out in a delta \nsomewhere around the Farallon Islands. \n3rd slide\, last slide on the fingerprinting study management \nquestion\, Tier 21 E\, Does mining in leased areas have the same \neffects on sand transport pathways? \nShould these areas be examined separately? \nThey can be treated separately\, we think different sand sources \nand spatial connections. \nAnd I’ll go over this figure in a minute. \nWell\, here we go. \nSassoon Bay is in the red. \nThe mining area is up here. \nThe red indicates the sand transport vicinity and pathways \nthat are conceptually interpreted from the mineralogy \nanalysis\, fingerprinting analysis. \nAnd it’s seems to\, you know\, link to San Pablo Bay\, maybe \nNorth Central Bay. \nCentral Bay is the blue and the sand seems to link very much \nwith the ocean and\, and the Bay and the ocean beaches. \nWe’ve got tidal exchange going back and forth and then there’s \nwave driven transport along the shore here. \nNext\, I want to talk about the USGS. \nThey did not author one of the three main studies\, but they \nsure did do a lot of work. \nAnd of course the US Geological Service\, our survey is well \nknown in the San Francisco Bay Area. \nThey’ve done a lot of great work in San Francisco Bay and on the \nPacific Coast\, including out at Ocean Beach\, etcetera. \nThey provided a a sediment transport boundary condition at \nthe upstream East End of Sassoon Bay. \nThey provided bathymetric change mapping and volume calculations. \nThis is a pretty heavy lift to\, to look at how the the Bay floor \nhas changed\, calculate how much the sand and mud and then Add \nall that up that\, that\, that was a\, a that’s a really big deal. \nAnd then they also provided they have a\, a\, a storehouse. \nThey have core\, sediment cores taken over decades and they \nprovided analysis and\, and grain size\, etcetera for mineralogy \nfor the fingerprinting study. \nThis graphic just shows where some of the cores were taken. \nThis graphic over here\, I hope you can see my cursor is shows \none of the cores from the top down. \nTop is younger\, bottom is older. \nAnd there’s some interpretation in terms of when the sediment \ndeposited and how quickly deposited between which periods. \nAnd this is just a generic grain size. \nWell\, actually it’s from the fingerprinting studies. \nSome of these are grab samples and not core samples\, but this \nthis shows you how some of the data were used. \nThe other major supporting entity is Deltauris\, world \nrenowned technical group out of Delft Institute in Netherlands. \nThey did what we called a more dynamic interpretation\, which \njust basically means how the sand moves and how the bed forms \nand and deposits change and how do you can interpret transport \ndirect pathways and and and at some points even rates from from \nthis kind of geomorphic analysis. \nWhat what we got out of that is the Central Bay sand transport \nis driven by tidal exchange to the Golden Gate with sand \nmigrating between the Bay mining areas\, flood tidal Shoals and \nthe San Francisco Bar ebtitle Shoals in the Pacific Ocean. \nAdditional sand transport waves along the shore into the Bay. \nSo this graphic here on the right\, the black and white one \nshows their interpretation of the main sand transport \npathways. \nThe thick black lines A is driven by ebb tidal flow\, B is \ndriven by flood tidal flow on the Oceanside. \nThis dashed line indicates where the San Francisco Bar is. \nThe waves push against the sand deposit by the tide\, so you get \na nice kind of horseshoe shaped feature where the two forces \ncollide and balance. \nOut on the Bayside you get a splay of of of tidal flood \ncurrent and a series of Shoals affected by the terrain and \ntopography. \nShoals behind Angel Island\, etcetera. \nThis is a blow up from the Delft. \nA larger image. \nThe Golden Gate is right here where the purple\, deep purple \ndepth is. \nThis is minus\, you know\, 80 meters or so\, 100 meters. \nAnd then this is Angel Island\, this white area which is over \nhere\, Alcatraz\, these black lines are the same as these \nblack lines over here. \nBut if you look closely\, you see little Red Arrows and you can \nalso see in this\, this is depth bathymetry. \nSo the tan is is up in the -20 meters or so and the blue is\, \nyou know\, much deeper around sixty\, 100 meters or 75 meters. \nAnd you can see these bed forms\, these sand waves\, which you can \ninterpret based on their asymmetry\, which way the net \nsand transport is moving. \nHere we have convergence\, which is kind of almost the definition \nof a Shoal\, if you will\, unless it’s eroding rapidly. \nAnd then so anyway\, they\, they analyzed all this and it was \nvery interesting and\, and we all looked at it\, it was great. \nSecond slide on Deltares bed changes in mining areas. \nSo the mining changes bed geometry. \nYou’re replacing natural bed forms like sand waves with \ndepressions and a lower bed elevation. \nYou see in this figure\, tan is is higher elevation bed of the \nBay and and blue is lower. \nSo the and the top is 1997 and the and the bottom is 2019. \nBrenda showed another version of this. \nHere’s the depth chart over here. \nWhat you can see in 1997 it was shallower\, the Tanner color and \nthen at by 2019 it’s deeper\, you know the bluer color. \nAnd you can also see\, you don’t really see these sand waves in \nhere. \nYou see these kind of irregular geometry\, localized geometry. \nSo what this tells us is that diffusion by currents and \nturbulence etcetera\, which would smooth the bed depressions is \nreally kind of limited within the time frame of the study. \nThese depressions seems to persist. \nInfill of the depressions is limited to less than 30%. \nSo this is the recovery rate if you will. \nSo in Sussoon Bay and North Central Bay\, there’s not much \nrecovery. \nThe the sand mining effects persist at least during the time \nframes and and locations we had data for and looked at except \nfor two Central Bay areas. \n1 is this one least 2036 point NOx Shoal and it\, it had a 55% \nrecovery between 2008 and 2019. \nSo that’s a different starting point than the 97. \nAnd then the Presidio Shoal\, which is the finer sand that \nthat was talked about earlier. \nI’m just used 100% that it was actually a little bit less and a \nlittle bit more depending on the time frame. \nSo that one’s really recovering. \nThis is very useful information. \nAnd this is an analysis that the ISP specifically asked for it. \nAnd just a little bit of an aside\, we talked about \nuncertainty. \nThere’s a lot of uncertainty in these analysis. \nBut if you look at how these studies were structured\, we have \na\, a sediment budget and a sand specifically also a sand budget. \nWe have a\, a numerical computer modeling based on computation to \nsand transport. \nAnd then we have this mineralogical historical \nanalysis\, source analysis tracking\, if you will. \nAnd then we also had this geomorphic analysis and all \nthese other things. \nSo these are different lines of evidence. \nAnd So what the ISP came up with is where we think these all kind \nof agree. \nAnd this is what I’m gonna present now\, a pretty distilled \none. \nOn the local scale\, depressions\, removal of sand waves and bed \nlowering occur where sand replenishment is low. \nThis is all of the mining areas in Suzun Bay and also the North \nCentral Bay mined areas where there’s 11 to 28% replenishment\, \nyou know\, precisely calculated. \nBut you see it’s say less than 30% reduced sand transport \noccurs we think where sand replenishment is high. \nAnd this is occurs in the South Central mined areas 709 S\, which \nwe talked about earlier\, the Presidio Shoal where there was\, \nyou know\, I said 100% in the prior slide. \nBut this is the range that was computed. \nAnd the idea is that if if there’s sand moving into through \nan area and you excavate that area and then that sand that \nmoves through fills it up or whatever drops out in that area \nto restore the bed form likely is a reduction to the sand that \nmoves through the area because the sand transport is thought to \nbe transport limited plus or minus. \nYou dig a hole\, sand deposits less sand goes out the other \nway\, and then the currents have to pick that sand up elsewhere. \nSo that’s an effect. \nThe Central Bayside I showed you again\, even with that depth \nchange\, we computed a 55% replenishment on the regional \nscale. \nSand mining exceeds sand supply. \nMine sand is relic delivered to the Bay thousands of years ago. \nSassoon Bay and Central Bay lease areas can be analyzed \nseparately due to the apparent limited sand transport \nconnection between them. \nA little bit of a surprise. \nSand is exchanged between the central Bay sand mining areas in \nthe sand Shoals and beaches on the Pacific side of the Golden \nGate. \nExchange is driven primarily by the ebb and flood of the tides \nwith contribution from wave driven sand transport into the \nBay along the shore. \nErosion of beaches due to sand mining was not investigated in \nthese studies. \nHere are the key data gaps. \nWe can discuss these if you want later\, but first\, the exchange \nof sand between the Bay and the Pacific Ocean. \nWe got some good information. \nI think we all feel like we could get into this a little \nfurther. \nIn particular\, understand what’s happening on the ocean side. \nWe kind of split this whole system in half or in parts and \nwe haven’t looked at the other side\, which would\, would help us \nunderstand what’s going on. \nSecondly\, the sand supply to Bay beaches is\, is of interest and \nwe\, we didn’t analyze that. \nI would say the sand supply to ocean beaches would would go \ninto item 1 sand transport pathways. \nWe\, we did\, we\, we did confirm and identify sand transport \npathways in these studies. \nBut within each of the\, let’s say sand budget sub embayments\, \nthere could be sand movement from say a source like say a\, a \nriver mouth or a Creek mouth that just recirculates landward \nand forms a beach and doesn’t propagate. \nYou know that sand may not propagate all the way through to \nthe\, to the ocean. \nSo those some refinement of the sand transport pathways and in \nparticular how the the beaches are linked to the deeper sand \noffshore sand supply. \n4th\, the variation of sand transport caused by grain size. \nThis is I guess one of the first\, certainly the most \nintense and detailed analysis of sand in San Francisco Bay at a \nBay level. \nAnd so there were some simplifying assumptions as we \ndiscussed at the beginning\, some of the questions grain size \nmatters with sand. \nAnd you know\, there may be different answers with the finer \nsands and the coarser sands. \nI’ll just leave it at that so that that’s something that could \nbe looked at further. \nOK\, I just\, I think we’re\, I’m done with the ISP presentation. \nHappy to for all of us to talk or answer questions. \nI just wanted to leave you with this picture that I took a \ncouple years ago thinking about this. \nThis is looking at\, you know\, the Golden Gate at the Presidio \nfrom Crissyfield Beach. \nYou can see some waves here coming in. \nThese are waves from the ocean. \nThey’re coming in through the Golden Gate and refracting \naround. \nYou can see this wave breaking. \nIt’s moving sand along the shore. \nThat’s called littoral transport and this is a beach with people \non it. \nAnd if we hung out here for a while\, we might see some birds \nand a few other things\, other animals. \nThis was not studied in the sand mining studies except based on \nthe limited available references and and Jim mentioned Chrissy \nfield deposition and I will\, I think I’ll just continue to \nshare. \nI don’t know if I did that or did somebody else do that\, but \nprobably me. \nBut are there any questions or should we go on to the \nstratigraphy study? \nWell\, I think what we need to do now and we are getting very \nshort of time. \nSo I don’t know if people have the ability to hang out for a \nlittle while after three. \nI’m hoping maybe they do. \nBut we do need to take down your slides for a SEC\, Bob. \nOK. \nAnd thank you so much\, Dave and Bob\, I think we need to have the \nopportunity for the sand miners to provide comments. \nYeah\, Sorry\, Pat\, if I stepped on your toes. \nNo\, that’s good. \nThat was one of the things I was going to say. \nAnd Brenda\, just a quick note. \nI have a hard stop. \nI have another Zoom call at three. \nOK\, we’ll try to move quickly because we want to get to the \nprovenance study. \nSo Erica\, I guess you’re still. \nYes\, we will have Aaron Holloway from GHC\, the consultant for the \nminers to present a couple of slides here. \nThank you. \nGreat. \nThanks. \nWelcome\, Aaron. \nHi. \nThanks for having me. \nLet me hold on a second. \nIt’s gonna be easier if I share a screen. \nSo our\, the\, the comments from the mining team are summarized \nin Appendix H Let’s see. \nSorry\, bear with me. \nThere you go. \nBut I would\, I just wanted to highlight kind of the sand \nbudget. \nYou know\, it\, it\, it was discussed quite a bit by Dave \nand\, and Bob and we recognize the value in the sand budget. \nBut as David said\, you know\, it’s really looking at inflows\, \noutflows in the change in storage. \nSo you know\, it’s transactions in a checking account\, but what \nit doesn’t include is\, you know\, the size of the savings account \nand the size of that sand reservoir. \nAnd we think that’s an important consideration in terms of how \nmuch sand is out there and available for mining. \nAnd so that’s\, that’s a key item that’s missing from the sand \nbudget. \nThe other one I think is\, was was was discussed\, but I feel \nlike is is not given enough attention is that the \nuncertainty in the direction at of sand flux at the Golden Gate\, \nit’s the most significant\, you know\, it has the highest\, it’s \nthe most uncertain term of the sand budget. \nBut I think a lot of the results we just saw\, you know\, jump to \nthe best guess that it’s\, you know\, oriented out and sand \nfluxes out toward the ocean. \nBut if you look at the uncertainty\, it could go either \nway. \nAnd and comments on the ISP report from Lester McKee\, you \nknow that I have quote from him at the bottom. \nDue to the\, the computation by difference and accumulative \nuncertainties\, the direction of flux at this location is \nuncertain. \nSo we would caution\, you know\, the\, the\, the commissioners from \nviewing that as a certainty. \nYou know\, it’s\, it’s not. \nAnd I think that’s\, that’s described in the studies. \nBut sometimes\, you know\, when trying to summarize things\, you \nknow\, we leap\, leap beyond this uncertainty. \nThe other concern we have in terms of the sand budget is the\, \nthe way mining was accounted for in addition to bathymetric \nchange. \nSo the USGS team studied the bathymetric change. \nTheir methods excluded the human disturbed act areas which were \nmining and dredging\, largely because those were going to be \naccounted for separately. \nYou know\, as as Brenda indicated\, there’s there’s \ndetailed volumes and records of the mining and the dredging. \nSo those were going to be accounted for separately in the \nbudget that so the bathymetry change should not have included \nthose areas. \nThat was the methods and that was kind of the the direction \nthat was shared by Bruce Jaffe during the quarterly review \nmeeting on this topic. \nBut when the SFEI team prepared their budget\, they included \nboth\, they included the mining areas in the bathymetric change \nvolume and then they accounted for them separately as well. \nSo while we acknowledge the sand mining is a large term in the \nsand budget\, to double count it\, you know\, is going to have \nsignificant error in the results. \nSo an example of that at Sassoon Bay here\, Sassoon Bay did not \nhave a lot of transport. \nYou could see the bathymetric change in this location outside \nof the mined areas is\, you know\, relatively shallow\, plus or \nminus half meter\, you know\, maybe 1m at most. \nBut the large black area there you see in that graphic\, this is \nthe mined area. \nSo that’s where a lot of the change is happening and the \nchange is due to mining. \nBut in the sand budget\, it’s accounted for once in the \nbathymetric change volume and it’s accounted for again as a \nmining volume\, essentially double counting it. \nSo that that ripple effect carries throughout the sand \nbudget because the sand budget assumes the system is all \nconnected. \nIf that is corrected and the sand budget bathymetric change \nis\, is kind of accounted for separately than the mining as \nintended by the USGS team\, the results are significantly \ndifferent. \nYou know\, we have a different direction and a much greater \nmagnitude of inflow of sand to the Bay. \nAnd then comparing the conceptual model that Bob \ndescribed from from the UT Austin team where we have sort \nof two distinct sources of sand somewhat disconnected that \ndoesn’t align well with the sand budget as currently presented. \nThe sand budget\, you know\, indicates this flow of sand \nthroughout the Bay\, which if that were the case\, you would \nexpect there to be some more consistencies between the the \ntype of sand and the source of sand. \nSo if the corrections are made in the way the mining is \naccounted for\, these arrows change significantly. \nSo Pacific Ocean becomes a source of sand for the central \nBay and then the flux between Sassoon Bay to San Pablo and the \nflux to central Bay become a lot lower. \nAnd that looks a lot\, a lot closer to the conceptual model \ndescribed here. \nSo we’ve got other comments about speculation of mining \nimpacts and\, and\, you know\, the lack of prior research \nconclusions that were brought in from the environmental teams\, \nbut I’m not gonna go into those. \nI’ll\, I’ll turn it back over to the team. \nThank you. \nDo the miner\, do the miners have anything else they wanted to \npresent or was that the end of it? \nNo\, Greg\, we’re\, we’re just keeping it brief in the interest \nof time. \nOh\, I totally appreciate that. \nI I wanted to say that I think that we should have any \ndiscussion and we can always do the next presentation at a \ndifferent meeting. \nI want to make sure that the commissioners get a chance to \ndiscuss anything they need to discuss or want a questions they \nhave at this point. \nAnd if there aren’t any\, then obviously we can move on to the \nnext presentation. \nBut I\, I did think that was probably the point of all of \nthis. \nYeah\, yeah. \nI would just want to say\, sorry to jump in\, out of place here\, \nbut we’re\, we’re very fortunate to have the\, the UT people \nonline. \nSo I think it would be a shame if after they did all this \nwithout getting paid that we didn’t let them speak. \nSo it wouldn’t be easy for them to speak at the next meeting. \nThey would have to\, need to speak now. \nAll right\, Well\, I don’t know. \nI\, I just\, that’s my opinion. \nFor what it’s worth. \nI\, I probably spoke out of turn\, But no\, no\, it’s a good question \n’cause obviously we want to hear from them. \nI was just thinking we could hear from them next. \nBut if that’s what that’s what we need to do\, yeah\, I’ll have \nto ask them. \nI’ll ask them indirectly\, I mean\, in the chat while you guys \ntalk. \nWell\, if there’s a question from the commissioners\, I was just\, I \nI do have a question. \nYeah. \nMy question is\, was anything\, did you look at what those \ndepressions were filled in with? \nWere they filled in with the same kind of sand grains that \nthey were taken or were they filled in with silt? \nI always think of this that the Bay is a very silt rich \nenvironment. \nSo So what were those holes filled in with? \nI’ll jump in on that and maybe Dave or somebody else can help \nme. \nThose areas are hydraulically too active to contain much mud. \nLet’s just use that. \nSilt would be the coarser side of that\, in my opinion. \nThere were some attempts to look at cameras and\, you know\, camera \nshots\, but it’s it’s a very active area. \nIt’s very hard to see. \nIt’s pretty deep. \nYeah. \nYou know\, if you are a hard hat diver with big heavy boots\, you \nprobably fall over and get buried. \nI’m not quite sure. \nI mean\, it’s a pretty tough place to to see\, but I don’t \nknow if anyone else has more\, you know\, better\, more specific \ninformation. \nDavid\, would you wanna help me out with that? \nDid I? \nDo you agree with me? \nYes\, I agree\, Bob. \nThe basic of the current pad\, the currents are so strong there \nthat the silts and the clay material does not settle there. \nSo it is the course of material settles in those depressions. \nThank you. \nThat that that’s what I wanted to know. \nAppreciate it. \nSo we can move on as are are there do any other commissioners \nhave a question? \nAndy Gunther. \nYeah\, I have a question. \nBut maybe we wanna push this discussion to the next meeting\, \nBrenda. \nBut but yeah\, I think well\, I think one of the important \nthings. \nLet me just pass up my question please. \nThe question is again about the uncertainty at the Golden Gate \nand the\, the and this I’m now unclear about the double \ncounting. \nI thought that we had a quote from he saying that we’re not \ngonna include the dredging site so there won’t be double \ncounting. \nBut it sounds like we have another presentation suggesting \nthere was double and therefore the numbers in terms of the \nNetflix at the gate look very different\, which again\, I \nthought was uncertain anyways. \nAnd so it’s a I\, I’m not sure how Brenda\, I’ll defer to you \nabout to how we\, we\, we work on this issue. \nBut I need some more time to kind of understand the debate \nhere and then its implications for how\, what what we we are \nthinking about in terms of permitting additional sand \nmining and and what the various benefits and risks are. \nYeah. \nAnd what I was going to say\, and I apologize\, apologize for the \ninterruption\, is that this was the ISP findings for findings \noverview. \nWe will have Lester McKee. \nHe’s agreed to come. \nI don’t have the date right now\, but he has agreed to present on \nthe SAN budget\, which perhaps where is where this conversation \nwould be better had because then Lester who developed the budget \nwould be here to have that conversation. \nBut yeah\, can I\, can I jump in real quick? \nSo the ISP was aware of the\, of the\, this comment and it’s our \njudgment that the\, the budget was done correctly. \nSeveral of us have a lot of experience with budgets and we \nfeel that it was done correctly. \nI would suggest that it’s great to get pushed back or you know\, \ncritical review. \nI\, I\, I\, I would suggest a process to reconcile these \nconcerns and then report back. \nI think there might be a need for additional study to\, to \nspecific analysis to reconcile these perspectives. \nAnd I think it’s a healthy process\, even though I know it’s \nfrustrating when you have to make a decision. \nWell\, no\, I mean\, I\, that would be my preference would be that \nyou and Mr. \nHolloway talk this over and\, and\, and help at least clarify \nfor me whether whether you have found areas of agreement and you \nstill have areas of disagreement or whatever. \nSo that\, that\, that I don’t have to take my limited knowledge of \nthis and somehow make my own faulty decision. \nYeah. \nAnd I and I\, you know\, Aaron and I know each other and we all \nknow. \nSo this\, this it’s fine. \nI don’t really feel bad about the\, the challenges and I\, I\, I \njust don’t right now. \nYou know\, we’ve been working on this for a while. \nSo everyone’s out of money except\, I don’t know\, maybe \nAaron has more money than the rest of us. \nBut yeah\, but I think we could all work together and\, and come \nback with this resolved. \nIn my opinion. \nI\, I\, I would prefer to do it that way rather than\, you know\, \nargue about it\, frankly that\, that I hopefully I didn’t speak \nout a line again. \nI’m sorry\, I’m getting older. \nNo\, not at all\, but I thought that was great that you spoke. \nThank you. \nI\, I can just wrap it up. \nI\, I agree. \nI think if we can talk with Lester and the team\, that’d be \nhelpful. \nThis comment was made sort of after all the quarterly meetings \nwere held. \nAnd so there wasn’t ever a venue to really kind of talk this \nthrough. \nSo the results that were prevented at the last quarterly \nmeeting were much different than this final version. \nAnd so part of it was we just haven’t had that chance to talk \nthat through\, ask our questions and and understand the rationale \nbehind the final budget. \nSo we look forward to that happening. \nThat sounds to me like a great suggestion. \nBrenda\, can you kind of help that happen? \nI can help that happen. \nI will note that I’ve been chatting with Zach\, our next \npresenter in chat\, and he does\, as does Matthew\, teach classes. \nAnd so our next several meetings are scheduled during periods \nwhere he is teaching. \nSo we have 20 minutes now we could have him do the \npresentation or I can try to. \nLet’s have him do the presentation. \nYeah\, let’s do that. \nThat sounds great. \nOK\, Zach\, with that\, you’re on. \nSorry for the. \nNo problem at all. \nThis is an important discussion. \nAnd hopefully what I have to\, to present here will will provide \nsome context as well. \nSo let me get my screen shared and OK\, yes\, presentation. \nYep\, OK\, everybody can see this. \nYes\, great. \nOK\, well\, again\, I’m very happy to to be able to to speak to you \nall about the research that we’ve been doing. \nAnd since we’re a little short on time\, I’ll just go ahead and \nhit the high points. \nI’ll also note that I’ve made my slides hopefully pretty \nself-explanatory. \nSo anybody that wants to look at them later\, please feel free to \ndo so. \nAnd then Matt and I have also\, we’re in the process of \npublishing a lot of this work as well. \nSo that will be available and we’ll make people aware when \nthings are published. \nSo we’re gonna have to start with some kind of sedimentology \n101 background here and explain what a fingerprinting study is. \nAnd so a sedimentary system is comprised of some source region \nwhere sediment is being produced by erosion\, some area where that \nsediment is being transported. \nSo for source regions\, think mountains\, transport regions\, \nthink rivers\, and then some area where that sediment is being \ndeposited either along the river or somewhere out in the coast. \nAnd so I’ve\, I’ve kind of conceptualized fingerprinting \nhere by illustrating blue source regions\, red source regions and \nyellow source regions. \nAnd if we go into any point in a sedimentary system and we take a \nsample of the sand\, we can use the composition of that sand \nthat’s inherited from the unique geology and its source region to \nsay something about where it came. \nSo we go here\, we see red here\, yellow here\, where they mix in a \ndelta combination of red and yellow. \nAnd so there’s many different ways that we can do this with \nnatural sediment and we use several different methods for \nthis study\, but I’m only gonna talk largely about one of them. \nSo it’s also important to note that processes like climate and \ntectonics can change where sediment comes from in the same \nsystem through time. \nSo\, you know\, maybe in our baseline here\, we’re producing \nmore red sediment out to this delta ’cause it’s raining more \non the red mountains. \nMaybe in time too\, we shift and we’ve got more rain in the \nyellow. \nMaybe we’ve diverted the blue into the into the red. \nAnd so now we go out to the delta and we see\, OK\, we’ve got \na combination of dominantly yellow\, red\, blue\, so on and so \nforth. \nSo processes can change where sediment is coming from in a \nsedimentary system on the scale of of thousands of years\, \nhundreds to thousands to 10s of thousands of years. \nAnd so if we have information both on the age of the \nsedimentary deposit that we’re that we’re looking at and we \nhave the sediment fingerprints\, we can develop kind of a from \nwhere and when model for the history of sediment sources in a \nspecific sedimentary system. \nAnd that’s what we’ve done for San Francisco Bay. \nSo it turns out that California geology is particularly well \nsuited to doing this kind of study. \nSo here on the right\, I’ve illustrated the Sacramento and \nthe San Joaquin catchments and their major tributaries. \nThese are the dominant sediment sources for most of the sediment \nat least over longer time scales into San Francisco Bay. \nAnd so up north\, we have volcanics\, metamorphic rocks\, \nwe’ve got granite and the Sierra Nevadas. \nDown here in the South\, we’ve got some metamorphic rocks\, \nmostly a lot of this granite. \nAnd then in the Coast Ranges\, we have a mix of sedimentary and \nvolcanic rocks. \nSo we have different source geologies in these different \nregions. \nThe sediment that is being produced by each of these \nregions is going to have a different compositional \nfingerprint that we can use to talk about where sediment is \ncoming from and how that might change through time. \nSo the specific method that I’m gonna talk about is using \nuranium\, lead aged dating of a mineral called zircon. \nAnd this is a particularly useful tool in California \nspecifically in large part because California was once a \nsubduction zone. \nSo 10s of millions\, hundreds of millions of years ago\, there was \nan oceanic plate subducting into California. \nIt was glomming on a bunch of metamorphic rocks here in the \nwater. \nNow the Sierra Nevada\, there was an active magnetic arc that was \nin placing all the granite that is now in the high Sierras. \nAnd so one of the minerals that forms in these settings is this \nmineral zircon. \nSo zircon is very important here because it incorporates a little \nbit of uranium into its crystal lattice. \nAnd so once that zircon crystallizes in cooling magma \nchamber down here that will eventually become granite\, we \nset a uranium lead age decay clock. \nAnd so we can we can examine the specific age of crystallization \nof that zircon. \nAnd that age of crystallization is gonna be different in \ndifferent places along the Sierra Nevadas. \nAnd so once those plutons get uplifted\, these zircon get \neroded and transported out into the rivers carried out in the \nSan Francisco Bay. \nWe can use these age dates to get a fingerprint that’s pretty \nunique to the source region from which sand is eroding at any \ngiven time. \nAnd so as a specific example of this\, we can look at Half Dome \nand Yosemite. \nSo Half Dome and Yosemite is made of granite that’s about \n84\,000\,000 years old. \nSo when a zircon erodes from Half Dome\, it falls into the \nMerced River. \nThe Merced River carries it out into the San Joaquin River\, that \ncarries it out into San Francisco Bay. \nSo if we go out into the sand to San Francisco Bay\, we separate a \nlot of zircon into the sand. \nWe analyze the ages. \nIf we see a lot of 8084 million year old zircon\, we know that \nthere’s a lot of sediment coming from this part of the Sierras. \nAnd so California is very good for this because a lot of these \nbasement\, a lot of these rocks have been dated. \nPeople have been studying Sierra Nevada geology for many\, many \ndecades now. \nSo we have a very good understanding of where zorcon of \ndifferent ages are coming and being fed into this system. \nAnd Matt and I have been working for 10/10/12 years or so at this \npoint on generating these uranium lead age spectre\, these \nfingerprints for different sediment sources that feed into \nSan Francisco Bay. \nAnd so the rivers that are carrying sand out of the \nnorthern Sierras up here in the Sacramento catchment are very \nenriched in this 140 ish million year old age beat. \nAnd So what I’m showing here is we took a sample of sand or we \ntook multiple samples of sand. \nWe separated a lot of zircon out of them. \nWe dated them individually. \nAnd this is the Spectra of ages that we got out of the zircon. \nSo the sand up here coming from the north has a lot of zircon of \nthis age. \nThe sand coming out of the South\, the San Joaquin catchment \nhas a lot of zircon of this 80 to 100 million year old age. \nAnd the sand that’s coming out of the Coast Range is here has \nkind of a mix of these ages\, but importantly it has a lot of \nthese younger zircon ages as well. \nAnd so these are coming from younger volcanic material in \nlike the Napa and Sonoma Valley. \nSo each one of these regions has a very distinct fingerprint that \nsand that is derived from that region is going to have\, is \ngoing to inherit. \nAnd so we can use that leverage to talk about where sand in \ndifferent parts of San Francisco Bay might be coming from. \nAnd so for this study\, we got dredge samples from the mining \ncompany. \nSo some of these in Sassoon Bay are actually dredged from the \nlease blocks. \nAnd we also got some older core samples from older academic \nstudies. \nSame here in Central Bay. \nWe got a dredge sample from the deeper part of Central Bay\, \ndredge sample from Presidio Shoal. \nWe also have some samples from Crissy Field. \nWe’ve got samples from the outer coast beaches. \nAnd then we’ve also got samples from the far offshore. \nAnd so we took all the sand from these samples. \nWe separated all the zircon out of it. \nWe dated those individuals zircon to look for those age \nfingerprints to say is it coming from the Northern Sierra\, \nSouthern Sierra Coast Range. \nAnd so this is what that looks like. \nAnd so here we’ve highlighted the Bay head. \nSo the Bay head here is the Sassoon and San Pablo Bay \nsamples shown here in blue. \nThe central Bay samples are those that are in the Golden \nGate Strait and Central Bay dredge blocks down here. \nAnd then the yellow samples from the outer coast beaches. \nAnd so very importantly from these fingerprints\, we see that \nthe Bay head samples are dominated by this 140 ish \nmillion year old age peak\, consistent with derivation from \nthe northern Sierras\, whereas Central Bay and the outer coast \nare much more strongly related to the southern Sierras. \nAnd so if you haven’t seen sediment fingerprint data like \nthis before\, maybe this seems like kind of a subtle \ndifference\, but we can we can very rigorously statistically \ndemonstrate that these two regions\, the Bay head region and \nthe central Bay and outer coast region cannot be derived from \nthe same source. \nThe the source of the sand that was depositing that sand that we \nsampled must have been different between those two regions. \nSo back to this conclusion figure. \nSo these are just the basic conclusions from this work from \njust that data. \nThese two regions have different sand sources. \nThe Bay head is probably largely northern siren derived with \nmaybe some local drainages. \nCentral Bay and the outer coast have a much stronger southern \nsiren affinity. \nAnd it’s also important to note that I’m talking about the \nzircon data here\, but this is also supported by other \nfingerprinting methods like sand photography and geochemistry. \nThe same\, the same trends hold. \nI’ll also note that these trends hold over grain size as well\, \nright? \nSo the the sample from Presidio Shoal is indistinguishable by \nthese methods from the sample in the deeper part of Central Bay \nand all of the samples across the Student Bay are \nstatistically indistinguishable from each other as well. \nOK. \nSo we don’t just have the fingerprint data here\, which is \nvery useful. \nWe also have some information about the likely age of the \nsand. \nAnd so when I’m talking about age of the sand here\, I’m not \ntalking about the age that that sand last moved. \nI’m talking about the age of when that sand came into the San \nFrancisco Bay system originally. \nSo not the last time tides moved it\, but the time at which it was \ncarried from the Sacramento\, San Joaquin drainage into the San \nFrancisco Bay system. \nAnd so we’ve been able to directly date that kind of \nresidence time in two places here. \nSo these are from dredge samples provided by the miners here in \nCentral Bay. \nSo these are optically stimulated luminescence age \ndates. \nSo the date the last time at which the sample was exposed to \nsunlight. \nAnd so that could be the time at which it got into water deep \nenough to block sunlight or the time at which it was buried by \nother sediments\, preventing it from being exposed to sunlight. \nAnd so very interestingly\, the the sand here in Central Bay \nseems to be younger than the sand here in Sassoon Bay. \nThis sand is three\, 4000 years old. \nThis sand is a couple 100 to maybe 1000 years old based on \nour preliminary results. \nAnd I’ll talk about how we can improve this going forward. \nThe other data that we have here is we know the history of sea \nlevel rise since the last Ice Age across this part of the \nsystem from independent work that was done on sediment cores. \nAnd so we know that the shoreline during the last Ice \nAge was somewhere out here at the at the what is now the \nmodern continental shelf. \nSlip break and sea level pushed what would have been a combined \nSacramento\, San Joaquin Delta from this position back across \nwhat is now the continental shelf through Golden Gate Strait \nand back to its modern position up here in the Bay Head over the \nlast 18\,000 years or so. \nSo from this we can interpret our kind of transport age into \nthe Bay. \nSo it looks like most of the sand\, at least the sand that \nwe’ve been able to date is somewhere between a few 1000 \nyears old to there is some new sand in Sassoon Bay. \nAnybody that’s been to the lower Sacramento River knows that \nthere is some sand still moving in the lower SAC. \nBut at least what we’ve dated from the dredge samples\, it’s \nprobably a couple of 1000 years old. \nThe sand out here in Central Bay and the outer coast was probably \nlargely originally transported into the system several thousand \nyears ago when sea level was much lower. \nAnd subsequently maybe it’s been reworked and sloshed back and \nforth by waves and tides. \nBut the original date that it was transported back into the \nsystem is several 1000 years. \nOK. \nSo we can combine all this into kind of a model for transport of \nsand into San Francisco Bay through time. \nSo 18\,000 years ago\, we’re in a global Ice Age. \nSea level is 150 meters lower than it is in the modern. \nAnd at this time\, a combined Sacramento\, San Joaquin Delta \nsits at the shelf edge. \nThis is largely sand that’s being derived predominantly from \nthe Southern Sierras based on the fingerprints. \nAnd it’s probably leaving kind of a blanket of sand in a delta \nthat’s sitting out here. \nAs global sea level begins to rise\, this delta gets pushed \nback across what is now the continental shelf\, probably \nleaving a blanket of largely southern Sierra and derived sand \nacross what will become the continental shelf. \nAs sea level continues to rise\, sometime between about 8 and \n6000 years ago\, this delta gets forced back through the Golden \nGate Strait. \nSimultaneous to this\, for climate reasons that we’ll talk \nabout in a second\, the dominant source of sand coming into the \nSan Francisco Bay system shifts to the northern Sierras and \nperhaps other smaller local drainages over the next couple \nthousand years. \nSea level continues to push the Delta back to its modern \nposition. \nThe Bay head delta was about here at Browns Island about 4000 \nyears ago\, which is consistent with our residents time dating \nthe ages from those dredge samples. \nAnd then out here we don’t have any active sand input from the \ndelta in all likelihood based on this residents time history and \non our fingerprints. \nInstead this sand is probably largely being kind of reworked \nrelic sand via tides and waves from sand that was carried \nseveral thousand years ago\, plus active coastal erosion. \nObviously sea cliffs all over California are eroding via wave \naction and so active coastal erosion is also probably \ninputting a little bit of sand here. \nBut largely by the time we get to a few thousand years ago\, we \nhave these two disconnected sand transport systems. \nOK\, so why does the source of San Francisco Bay sand shift \nfrom South to north of time? \nWell\, during the last Ice Age there was an Alpine ice sheet \nacross the southern Sierras. \nIt turns out having an ice sheet on top of granite is a very \nefficient way to mechanically erode sand. \nAnd so during the last glacial period up until about 13\,000 \nyears ago\, this ice sheet was probably doing a lot of work \nmechanically eroding and producing a lot of sand out of \nthe southern sea eras through natural climate cycles. \nOver the subsequent 13\,000 years or so\, and this is evidenced by \na number of other independent climate proxies\, the southern \nsear and ice sheet starts to melt. \nThe southern Sierras get warmer and drier and regional \nprecipitation patterns shift more moisture to the northern \nSierras. \nAnd so we start raining more on the northern Sierras. \nWe melt all the glaciers. \nWe dry up the southern Sierras and so this is likely the reason \nthat the sediment sources shift towards the northern Sierras \nover the last couple 1000 years. \nOK\, so back to the conclusions real quick. \nWe can come back to these in a second\, but there is one more \nthing that that I want to note in terms of this luminescence \ndating. \nAnd so this type of luminescence dating\, luminescence dating \nthese dredge samples from the sea floor was something that we \nhad thought from the literature was conceptually possible\, but \nthis was the first time that had been demonstrated to be \nparticularly effective. \nNo one had ever done this kind of thing before\, at least in \nterms of dredging up sand and trying to date\, you know\, sand \nin a sand mining lease block. \nAnd so we think that a broader expansion of this OSL dating \nwould be a very valuable thing to potentially add to future \nunderstanding of sand transport. \nIf we know things like how frequently is sand in Central \nBay being recycled through beaches? \nHow totally is sand that’s coming in from the river being \nbleached? \nHow long has sand in different parts of the system or different \ndepths within the subsea floor sand reservoir\, how long it’s \nbeen there? \nThat’s potentially a very valuable thing to understand to \nour broader understanding here. \nAnd so with that\, I’ll\, I’ll just stop. \nAnd I\, I will also end with a picture of Chrissy Field because \nwe also took a sample there. \nAnd I’m very happy to\, to answer any questions. \nAnd Matt Malkowski\, I think is still on the call too\, so he can \nadd some perspective if he wants. \nOK. \nSo do the miners have any comments at at this point that \nthey’d like to share? \nErica Yes\, just real quick\, we’re going to provide a couple \nof comments on this study and Aaron again will be doing that \nfor us. \nThank you. \nYeah\, thanks\, Erica. \nI\, I don’t\, I don’t have a whole lot to add to to the study. \nI think I’ll just use this time and let the commissioners ask \nquestions. \nI\, I didn’t see any major concerns or we don’t have any \nquestions or issues with the methods applied. \nOK\, well\, I do have a question and it’s\, I think this is just \none of those things for years I’ve heard about. \nIt’s sort of like the\, the\, you know\, the folk history of \nsediment in San Francisco Bay is that it all came from the gold \nrush. \nSo what happened to the sediments that worked through \nthe system into the gold rush? \nI remember reading an article by Patrick Bernard maybe 10-15 \nyears ago where he said they were all worked through\, but you \ndidn’t mention them. \nSo where do they fit in this? \nZach\, you’re\, you’re asking all the good questions today. \nYou’re nailing it. \nYes. \nSo that is definitely true. \nAnd there’s demonstrated evidence that the Bay floor rose \nparticularly with fine sediment after the gold rush. \nAnd so there’s a\, there’s a couple of\, there’s a couple of \nreasons. \nSo this is\, this was this was a question that we entertained and \nwe’re still entertaining. \nThere’s a couple of reasons why we don’t think that that is the \nspecific explanation for what we’re seeing here. \nThe most important of which is that this sediment at least a \nlot of what we’ve dated is thousands of years old or \nhundreds of years old based on the residents times. \nAnd so it’s way\, way\, way before the gold rush. \nAnd so this was something that we originally incorporated and \nhave incorporated into subsequent proposals about \ntaking sediment cores and actually seeing if we can see \nthat effect of gold rush sand coming in. \nBut from everything that we’ve seen in the sand size fraction\, \nthe sand that we’re looking at probably predates most of the \ngold rush. \nA lot of the sediment that was washed out and started to fill \nin parts of San Francisco Bay during the hydraulic mining. \nWas fine silt and mud. \nA lot of the sand that was produced there is still probably \nsequestered up in the upper parts of the Sacramento River \nand the tributaries. \nSome of it probably made it down. \nBut we think that the broader climate effect over the last \ncouple thousand years is what we’re seeing as opposed to the \nmuch shorter time scale effect of the hydraulic mining\, which \ndefinitely puts sediment into San Francisco Bay. \nBut everything that we see seems to indicate that the sediment \nthat we’re looking at is older than that. \nThank you. \nSo in other words\, the glaciers\, the machines of the glaciers \nwere just really what dominated the systems that you found. \nOK\, Great. \nCommissioner Gunther. \nYeah. \nFollowing up on that\, I wanted to ask a question about \ntransport and about the whether we know. \nSo for example\, in 1862 with the great flood\, do those\, does a \nwinter like that have the ability to pick up a whole bunch \nof that sand that’s still hanging out in the Sacramento \nRiver in the wherever the Merced River slows down and things drop \nout\, pick it up and throw it into Sassoon Bay in one fell \nswoop? \nI mean\, so that that that the horizontal transport across the \nlandscape can be very episodic. \nAnd so do we know anything about to be able to say something \nabout that? \nSo that the ’cause it would seem to me\, I guess I’m trying to \nunderstand whether there could be an overlay that’s on the \nscale of decades based upon major storm events against this \nthousand year story that you just told us\, right. \nYes. \nSo\, so that is definitely the case that there should be pulses \nof\, of sand sized sediment into the Bay. \nBut I\, I think the kind of perspective to take here is the \nfact that anything that does come into the Bay here is gonna \nbe mixed with anything that’s already there via title action. \nAnd what we’re talking about in terms of these time integrated \nthousand year time scale changes in sediment history is gonna \nswamp out any very short time scale introduction of new \ndifferent sand. \nAnd so the bulk of the sand that is sitting here seems to be \nprobably thousands of years old. \nIt’s been there\, it’s been there for quite a while. \nAnd so that’s thousands of years of volume of sand being in \nthere. \nThat if we’re looking at a dredge sample in particular\, \nthat’s not just sampling the upper\, you know\, couple \ncentimeters of the sea floor\, but it’s integrating\, you know\, \nmeters down deep. \nThat 1000 year integrated signature is not gonna pick up \nthose shorter time scale pulse events\, at least not with the \nthe methods that we’re using here\, right. \nBut if you’re facing questions about regulating or not \nregulating sand mining on the scale of\, of these activities\, \non a scale of a decade\, I’m very impressed by the fact that Fort \nKnox show you can dig a hole and it’s still there and you go down \njust over across the channel of the Presidio\, you dig a hole and \nit disappears. \nIt’s filled back in and\, and\, and it sounds like up at Sassoon \nBay\, we dig a hole and it stays there. \nBut does it stay there until we have a great flood and then it \nfills up completely? \nI’m trying to understand whether we can anticipate\, you’re right. \nHow does that this is the problem when you have biologists \ntalking sediment? \nIt’s like that the rate at which the change occurs in the \nenvironment is a key thing for us to understand and assess \nimpacts\, right. \nSo I\, I think that in part your question is probably better \nanswered by a sediment transport modeler. \nBut one thing that I will say is that when we were doing this \nstudy\, we actually had a really hard time finding sand in \nshallow cores in this area. \nAnd so a lot of the\, a lot of the cores that we had access to \nwere old USGS cores and maybe a meter\, maybe a little bit more \nthan a meter if we’re lucky in\, in total depth. \nAnd we had a really hard time finding near surface sand. \nAnd so the sand samples that we got here are dredge samples that \nwere provided from the lease blocks from the mining companies \nwhere they’re going\, you know\, deeper than what a three inch \naluminum pipe from the USGS was going\, you know\, a meter or so. \nWe were anecdotally surprised how little near surface sand \nthere was in these areas when we were trying to find samples of \nsand to analyze. \nThank you. \nHey Zach\, do you wanna take your slide down? \nMaybe? \nOh\, yeah\, yeah. \nThanks. \nSorry. \nWe can see you better that way. \nBrenda\, could I try to answer or\, or throw in my 2 bits for \nCommissioner Gunther’s question? \nI\, I\, I think that in the\, over the past few years\, and I forgot \nthe exact war year 2018-2019\, there was a very large\, you \nknow\, you’ve had some really large flow events during this \nsand mining study. \nThat have not filled in the Sassoon Bay mining areas with \nsand. \nNow some things have changed geologically very recently\, such \nas construction of lots of dams on the Central Valley rivers\, \nconstruction of\, you know\, the use of like the yellow bypass \nfor trapping sand or that’s the net effect of it. \nAnd also that the the the glaciers that Zach mentioned \nthat we’re producing a lot of the sand are no longer present \nin the Sierras. \nSo there have been some changes like that also. \nThat would all account for that now when we have. \nBut for us in our highly regulated Central Valley \nwatershed\, when we have a big flood event\, it just isn’t \ndelivering that sand anymore to to Sassoon Bay like it did \nperhaps 102 hundred\, 500 years ago. \nI don’t know if that helps. \nYeah\, obviously I’m being influenced as well by the \nchanges in the fines and how that’s affect the phodic depth. \nJust Wednesday at the water board\, we made a huge decision \nabout nutrient\, future nutrient treatment in the Bay because \nwe’re not getting the the we’re we’re getting a lot more \nproduction because we have a lot less turbidity in the system. \nSo\, but this then makes it so\, so I’m getting the impression \nthat that that\, you know\, sort of what we see is what we get on \non the scale of thousands of years that we’re not seeing \nshort term fluctuations. \nAnd and and and Zach\, I just got to say this was fascinating. \nThank you so much. \nI this is really great stuff. \nI I everything. \nEvery time I think I know something about the Bay\, I \nlearned something more. \nAnd thank you\, Brenda\, for putting this program together. \nIt’s really great. \nYeah. \nI’m just also going to to query the slides will be available on \nthe website or will they not be available on the website? \nWhat’s to do with the slides? \nYes\, so we\, I put it in the chat a little earlier. \nAll of the three presentations that were given today will be \ncombined in are combined into one PDF and they will be on the \nwebsite. \nWe actually tried to post them this morning. \nI looked\, they’re not there yet\, but if you go under the \nCommission tab and look for commissioner working group\, \nyou’ll find this sediment study or SAN studies Commissioner \nworking group. \nLook there\, that’s where they’ll be. \nAnd I just chatted Aaron separately and he said he would \nprovide his slides as well. \nSo we can add those to the available slides so that the \ncommissioners and members of the public\, other interested folks\, \nif you’re not a member of don’t know who you are and take a look \nat those slides as well and kind of compare apples to oranges. \nAnd as I\, as I mentioned\, we will do it. \nWe will likely have Lester McKee at one of the next meetings to \ntalk more about San budget and we can have a fuller \nconversation about that as well there. \nAnd then Brenda\, we will also have a chance in the future to \nlearn more about some of the nuts and bolts of what it means \nto mind sand from the Bay and hear more from the industry. \nYeah. \nSo what the\, what the plan for this working grip? \nIt’s a very short\, short lived. \nNow we’ve had the Providence report and we could time stamp \nthis commissioner working group. \nIt is scheduled to last through November. \nThere’s a total of 4 meetings. \nThe next one is August 21st and it’s a 11:50\, so not quite as \nlate in the day. \nThanks for everybody who’s hung out with us this long on a \nFriday. \nAnd the concept that we’re working with is the \ncommissioners asked a series of questions\, the studies responded \nto those questions\, also the management questions. \nAnd so we’re going to structure the agenda around having a study \nor two\, depending on the breadth of the study and what we think \nthe conversation will take over the next two meetings. \nThe fourth meeting that we have\, I think we’ll probably talk and \nI don’t have this all completely laid out\, but we’ll talk about \nsome of the Bay Plan policies. \nWe will\, I think\, get to some of the commissioners questions from \nthe Commission meeting and yours\, Andy\, like how much of \nthe sand is used in the Bay region? \nAre there alternatives\, some of that as long as we’re all \nefficient and get through the sand studies\, we’ll have those \nor at a meeting or something. \nAnyways\, so that’s the plan. \nWe’re going to hit the studies you grounded in the science and \nthen talk about broader. \nI’m going to say societal and policy issues. \nSo I also want to say\, commissioners\, that it is your \nworking group\, Yes. \nAnd if there are questions that you want answered and if you \nwanna have another meeting or are there topics that you think \nabsolutely have to be covered or needed to be covered. \nI mean\, I would definitely encourage you to tell staff \nbecause I view this as yours not run by staff. \nWell\, I for 1:00 AM really glad that we’re gonna have these \nslides to look at because particularly those graphs\, I \nneed to think about them some more before I finish with my \nlist of questions. \nSo I’m glad they’re going to be available and but they really \nare fascinating science. \nSo this is a wonderful opportunity for all of us. \nDo the minors. \nI know we want to make sure that that group is represented in \nquestions and comments. \nDo you have any things that you would like to share at this \npoint? \nWe’ve appreciated what you’ve had so far. \nNot not right now that I would be remiss to if I don’t say \nthat. \nYou know\, we also are very excited about a lot of the \nscience work that was done here and all the effort that was put \ninto all the\, the numerous\, numerous meetings and the \nnumerous discussions. \nSo you know what\, there are things that are still need to be \naddressed\, and that’s why we had those points\, you know\, being \npart of the appendix of the report. \nBut overall\, we feel very pleased with\, you know\, all the \neffort that was put into these. \nGreat. \nOK. \nWell\, I think that brings our meeting to a close. \nPat\, before that\, you need to just legally ask for public \ncomment. \nThat’s right. \nOf course we do\, yes. \nDo we have any public comment? \nIf there’s anybody who would like to make a comment at this \npoint\, please raise your hand and zoom and we will give you 3 \nminutes. \nSeeing none\, I’ll move to adjourn. \nAnd thank you everyone for your attention and for the great work \nthat you’re sharing with us. \nIt’s it’s much appreciated. \nOK\, bye. \nBye. \nThanks\, everybody. \nThank you. \nThank you so much. \n \n\n \n \n \n \n \n \n Learn How to Participate\n Bagley-Keene Open Meeting Act\nAs a state agency\, the Commission is governed by the Bagley-Keene Open Meeting Act which requires the Commission to: (1) publish an agenda at least ten days in advance of any meeting; and (2) describe specifically in that agenda the items to be transacted or discussed. 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URL:https://www.bcdc.ca.gov/event/july-12-2024-sand-studies-commissioner-working-group/ CATEGORIES:Sand Studies Commissioner Working Group END:VEVENT END:VCALENDAR