Soil Sampling and Analysis Report.pdf

GeoPentech

SAMPLING AND ANALYSIS REPORT

Suisun Bay Channel and New York Slough 2019 Maintenance Dredging

USACE Contract No. W912P7-16-D-0005

Prepared for:

U.S. Army Corps of Engineers

San Francisco District San Francisco, California

Prepared by:

DiazYourman – GeoPentech – Kinnetic Laboratories/ Joint Venture

1616 E. 17th Street Santa Ana, CA 92705

May 2019 i

Suisun Bay Channel and New York Slough 2019 Maintenance Dredging USACE Contract No. W912P7-16-D-0005

May 2019

TABLE OF CONTENTS

Page No.

1.0 INTRODUCTION

2.0 ROLES AND RESPONSIBILITIES

3.0 HISTORICAL DREDGING AND DATA REVIEW

4.0 METHODS

4.1 Sampling and Testing Approach

4.2 Sampling Methods

4.2.1 Positioning and Depth Measurements

4.2.2 Vibracore Sampling Methods

4.2.3 Core Processing

4.2.4 Documentation and Sample Custody

4.3 Laboratory Testing Methods

5.0 RESULTS AND DISCUSSION

5.1 Sediment Observations

5.2 Sediment Solids and Organic Carbon Content Results

5.3 Sediment Grain Size Results

5.4 Analytical QA/QC

6.0 CONCLUSIONS

7.0 REFERENCES CITED

APPENDICES

APPENDIX A – Figures of Proposed and Sample Locations and Condition Survey

Conducted March 2019 APPENDIX B – Core Photographs APPENDIX C – Field Data Log Sheets APPENDIX D – Hushmand Associates Data Report and Grain Size Distribution Plots APPENDIX E – Euorfins Calscience Laboratory Report ii

LIST OF TABLES

Page No.

Table 1. Volume Estimates from March 2019 Condition Survey Table 2. Project Team and Responsibilities Table 3. Key Project Contacts Table 4. SBC Dredging History Table 5. 2009 and 2014 SBC Sediment Chemistry Results Table 6. Actual Sampling Locations, Core Depths, Mudline Elevations, and Sampling

Elevations for the SBC Cores Table 7. 2019 SBC Composite Sediment Total Organic Carbon Content and Percent Solids

Data Table 8. 2019 SBC Composite Sample Sieve Analysis Data Table 9. Counts of QC records per Chemical Category

LIST OF FIGURES

Page No.

Figure 1. Locations of the Suisun Bay Channel and New York Slough and the SF-9 and SF-16 In-Bay Disposal Sites iii

LIST OF ACRONYMS

ASTM American Society for Testing and Materials

COC

CTR

CVRWQCB

Chain of Custody California Toxics Rule Regional Water Quality Control Board, Central Valley Region

CY Cubic Yards

DGPS Differential Global Positioning Satellite

DMMO Dredged Material Management Office

LCS

ITM

Laboratory Control Spike Inland Testing Manual

LDPE

MCL

Low Density Polyethylene Maximum Contaminant Level

MDL

MLLW

MS

NA

Method Detection Limit Mean Lower Low Water Matrix Spike Not Applicable

NAD North American Datum

OBDS Ocean Beach Demonstration Site

O&M Operations and Maintenance

OTM Ocean Testing Manual

PAH Polycyclic Aromatic Hydrocarbon

PCB

QA

QC

RL

Polychlorinated biphenyl Quality Assurance Quality Control Reporting Limit

SAP Sampling and Analysis Plan

SAR Sampling and Analysis Report

SBC

SFBRWQCB

Suisun Bay Channel San Francisco Bay Regional Water Quality Control Board

SOP Standard Operating Procedure

TOC Total Organic Carbon

USACE U.S. Army Corps of Engineers

USCS Unified Soil Classification System

USEPA

WDRs

U.S. Environmental Protection Agency Waste Discharge Requirements iv

This Page was Left Intentionally Blank

Suisun Bay Channel and New York Slough 2019 Maintenance Dredging USACE Contract No. W912P7-16-D-0005

May 2019

1.0 INTRODUCTION

Annual maintenance dredging is required in portions of the Suisun Bay Channel and New York Slough, collectively called the Suisun Bay Channel (SBC). Maintenance dredging occurs under the USACE, San Francisco District Operations and Maintenance (O&M) Dredging Program to prevent navigation hazards to deep-draft commercial vessels transiting the SBC to ports at Concord, Pittsburg, Antioch, Stockton and Sacramento. Most of the SBC has an authorized depth of -35 feet Mean Lower Low Water (MLLW) plus two feet of allowable overdepth. The Bulls Head Reach portion of the SBC between Stations 62+00 and 88+00 (Figure 1) typically shoals in quicker and as such has an advanced maintenance depth of -37 feet MLLW plus two feet for allowable overdepth.

The SBC (Figure 1) is a 300-foot wide channel located thirty miles north of San Francisco in Suisun Bay oriented in a northeasterly direction from Bulls Head Point (near the Benicia-Martinez Bridge) toward Roe Island. At Roe Island, it turns towards the southeast to the mouth of the New York Slough, covering a total distance of approximately thirteen miles. New York Slough is also 300 feet-wide, starts in Pittsburg, and continues for four more miles in a southeast direction to the City of Antioch.

Sampling and confirmatory testing of the SBC sediments occurs every five years according to a schedule agreed upon by the United States Army Corps of Engineers (USACE) and the San Francisco Bay Dredge Material Management Office (DMMO). Sampling and testing last occurred prior to the 2014 dredging episode and the sampling schedule calls for testing prior to the 2019 dredging episode. As such, this Sampling and Analysis Report (SAR) has been prepared on behalf of USACE, San Francisco District to summarize procedures conducted and results obtained for the sampling and testing of sediments from the SBC that occurred in 2019. This work was performed under USACE Contract No. W912P7-16-D-0005. All work described in this SAR was conducted in accordance to the approved Project Sampling and Analysis Plan (SAP) (USACE, San Francisco District, 2019) and the USACE Master SAP for O&M Dredging (USACE, San Francisco District, 2014).

The United States Environmental Protection Agency and USACE dredge material testing manual (USEPA/USACE, 1998) provides an allowance for predominantly sandy soils with low organic carbon content to be exempt from Tier II (chemical) and Tier III (biological) testing since sandy sediments are not known to be carriers of elevated contaminants. Historic sampling results have generally shown low levels of metals and butyltins and very low or non-detect levels of Polyaromatic Hydrocarbons (PAHs), pesticides, and Polychlorinated Biphenyls (PCBs). As such, a Tier I exclusion from additional testing over the next five years is being sought for the SBC sediments based on previous analytical and physical data, provided the SBC sediments have a greater than 80% sand content.

Figure 1. Locations of the Suisun Bay Channel and New York Slough and the SF-9 and SF-16 In-Bay Disposal Sites.

The USACE plans to dredge SBC sediments in August 2019. The purpose of this project was to sample and test sediments from shoaled areas within the federal channel limits proposed for 2019 O&M dredging in order to confirm sediment grain size necessary for satisfying Tier I requirements. Shoaling in the SBC based on a March 2019 bathymetric survey (Appendix A) is estimated to be 47,672 cubic yards (cy) (Table 1). This volume includes a two-foot overdepth allowance. Since shoaling is an ongoing natural process in the SBC, the total volume of material to be dredged is projected to reach as much as 175,000 cy prior to O&M dredging. The in-bay disposal site at SF-16 is the preferred aquatic location to place the dredged material with SF-9 as an alternative. The dredge material may also be reused at some not yet identified beneficial reuse site. Figure 1 identifies both in-bay placement sites.

Table 1. Volume Estimates from March 2019 Condition Survey.

2019 CURRENT DREDGE QUANTITIES and AREAS

Suisun Bay Channel & New York Slough (Excluding Bulls Head Reach) Depth (Feet MLLW) Quantity (CY) Area (Acres)

Mudline to Design Depth (-35): 11,400 10.5 1st Foot of Overdepth Allowance (-35 to -36): 16,899 NA 2nd Foot of Overdepth Allowance (-36 to -37): 16,899 NA

Total to -37: 44,938 10.5 2019 CURRENT DREDGE QUANTITIES and AREAS

Bulls Head Reach Depth (Feet MLLW) Quantity (CY) Area (Acres)

Mudline to Design Depth (-37): 291 1.0 1st Foot of Overdepth Allowance (-37 to -38): 1,222 NA 2nd Foot of Overdepth Allowance (-38 to -39): 1,222 NA

Total to -39: 2,734 1.0 Project Total: 47,672 11.5

2.0 ROLES AND RESPONSIBILITIES

Project responsibilities and key contacts for this sediment characterization program are listed in Tables 2 and 3. Kinnetic Laboratories Inc. provided sampling services. Kinnetic Laboratories with assistance from Diaz Yourman and Associates prepared this SAR. Hushmand Associates, Inc. and Eurofins Calscience carried out the laboratory testing for this project.

Table 2. Project Team and Responsibilities.

Responsibility Name Affiliation

Project Planning and Coordination

Joseph Viola Edward Keller

Christopher Diaz Ken Kronschnabl

USACE

USACE

Diaz-Yourman Kinnetic Laboratories

Sampling and Analysis Plan (SAP) Preparation Edward Keller USACE

Field Sample Collection and Transport Spencer Johnson

Greg Cotten Shaun Stringer

Kinnetic Laboratories Kinnetic Laboratories Kinnetic Laboratories

Health and Safety Officer Greg Cotten Kinnetic Laboratories

Laboratory Analyses Kang Chieh Lin

Julie Lam Hushmand Associates Eurofins Calscience

QA/QC Management Amy Howk Kinnetic Laboratories

Technical Review Mark Savoie

Edward Keller Kinnetic Laboratories

USACE

Final Report Ken Kronschnabl

Amy Howk Kinnetic Laboratories Kinnetic Laboratories

Agency Coordination Edward Keller USACE

Table 3. Key Project Contacts.

Joseph Viola

COR

U.S. Army Corps of Engineers A-E Services Unit, 450 Golden Gate Avenue, 4th Floor San Francisco, California 94102-3406 Phone: 415-503-6883 Email: Joseph.J.Viola@usace.army.mil

Edward Keller TPOC Technical POC U.S. Army Corps of Engineers Environmental Section B, 450 Golden Gate Avenue, 4th Floor San Francisco, California 94102-3406 Phone: 415-503-6841 E-mail: Edward.P.Keller@usace.army.mil

Chris Diaz Joint Venture Project Manager Diaz Yourman & Associates 1616 East 17th Street Santa Ana, CA 92705-8509 Tel. (714) 245-2920 chris@diazyourman.com

Ken Kronschnabl Project Manager - Sampling/Testing Kinnetic Laboratories, Inc. (KLI) 307 Washington St.

Santa Cruz, CA 95060 Tel. (831) 457-3950 kkronsch@kinneticlabs.net

Spencer Johnson Field Operations Mgr.

Kinnetic Laboratories, Inc. (KLI) 307 Washington St.

Santa Cruz, CA 95060 Tel. (831) 457-3950 sjohnson@kinneticlabs.net

Amy Howk KLI QA/QC Management Kinnetic Laboratories, Inc.

307 Washington St.

Santa Cruz, CA 95060 Tel. (831) 457-3950 ahowk@kinneticlabs.net

3.0 HISTORICAL DREDGING AND DATA REVIEW

USACE typically performs O&M dredging of the SBC annually. Table 4 identifies the dredged volumes and placement sites for the previous 10 years. On average, approximately 150,000 cy of material are dredged from the SBC annually, with the majority of the material going to SF-16.

Some of the material went to SF-9 in 2012 and 2013.

Table 4. SBC Dredging History.

Year Dredge Volume (cubic yards) Placement Site

2009 Essayons/Contract Dredge

238,390 (RM)

SF-16

46,637 (AM)

2010 Essayons/Contract Dredge 140,340 SF-16

2011 Essayons 252,008 SF-16

2012 Essayons 156,854 SF-16/SF-9

2013 Yaquina 132,566 SF-16/SF-9

2014 Yaquina 130,415 SF-16

2015 Contracted Clamshell Dredge 82,793 SF-16

2016 Not Dredged 0 NA

2017 Contracted Clamshell Dredge 195,130 SF-16

2018 Contracted Clamshell Dredge 130,341 SF-16

10 YR TOTAL 1,505,474

10 YR AVERAGE 150,547

The last two confirmatory sampling episodes of the SBC sediments occurred in 2009 and 2014.

Grain size, total organic carbon (TOC) and moisture content were determined for both sampling episodes. In addition, a Modified Waste Extraction Test (mWET) was performed on each 2009 sediment sample to determine leachable metals. A report prepared by ADH Environmental (2009) presents the 2009 results, and a report prepared by Environmental Cost Management (2014) presents the results of the 2014 sampling episode. Table 5 provides a summary of the confirmatory testing data for both episodes.

Four composite samples were analyzed for the 2009 sampling and testing episode. The sand content in these samples ranged from 94.7% to 99.3%, and the organic carbon content was low at 0.22% to 0.43%. According to the Project SAP, these results are typical of the sediments in that region of Suisun Bay.

The ADH Environmental (2009) report compared soluble metals results to San Francisco Bay Basin Plan (SFBRWQCB, 2007) and California Toxics Rule (CTR) (USEPA, 2000) numeric water quality objectives for marine waters, Waste Discharge Requirements (WDRs) applicable to maintenance dredging of the Stockton Deepwater Ship Channel (CVRWQCB, 2016), and California Public Health Drinking Water Standards (Maximum Contaminant Levels). The results show that soluble copper, lead, mercury and nickel exceeded CTR and/or Basin Plan marine objectives in one or more samples. Copper and lead also slightly exceeded WDRs for upland placement of Stockton Deepwater Ship Channel sediments. No sample results exceeded California MCLs.

Three composite samples were analyzed for the 2014 sampling and testing episode. The sand content in these samples was slightly less than measured in 2009 and ranged from 82.3% to 86.9% (Table 5). TOC was similarly low at 0.03% to 0.52%.

Table 5. 2009 and 2014 SBC Sediment Chemistry Results.

Analyte

June 2009 Results1 June 2014 Results2 Water Quality Objectives3

1 2 3 4 1 2 3 CA Toxics

Rule/SF Bay Basin Plan3,4

CA Drinking Water MCLs5

CVRWQCB

WDRs6

Grain Size (%) Sand/Gravel (>0.063 mm) 98.75 94.66 99.24 99.34 82.30 83.73 86.88 -- -- -- Silt (0.004 – 0.063 mm) 0.5 2.31 0.42 0.42 10.66 11.20 10.06 -- -- -- Clay (<0.004 mm) 0.71 2.7 0.3 0.61 7.04 5.07 3.07 -- -- -- Conventionals -- -- -- % Solids 80.8 73.8 77.7 72.4 72.8 73.0 76.4 -- -- -- TOC (%, dry weight) 0.22 0.24 0.43 0.3 0.52 0.21 0.03 -- -- --mWET Soluble Metals (µg/L) Arsenic 9.6 6.5 8.8 11.3 -- -- -- 36/69 10 10 Cadmium 0.012J 0.045 0.045 0.046 -- -- -- 9.3/42 5 5 Chromium 1.95 14.6 14.3 13.6 -- -- -- 50/1100 50 50 Copper 3.24 9.76 6.71 6.75 -- -- -- 3.1/4.8 1300 9 Lead 0.586 3.62 4.67 8.77 -- -- -- 8.1/210 15 2.5 Mercury 0.00243 0.0454 0.00225 0.0013 -- -- -- 0.025/2.1 2 0.05 Nickel 1.46 13.7 13.5 13.2 -- -- -- 8.2/74 100 52 Selenium 0.32J 0.29J 0.39J 0.53J -- -- -- 5/207 50 5 Zinc 4.67J 46.2J 51.7J 50.1J -- -- -- 81/90 5000 100

1. Suisun Bay Channel and New York Slough 2009 Maintenance Dredging Sampling and Analysis Report FINAL. ADH Environmental, July 2009 (ADH Env., 2009).

2. Suisun Bay Channel and New York Slough 2014 Maintenance Dredging Sampling and Analysis Report. Environmental Cost Management, Inc., September 2014 (ECM Inc, 2014).

3. Water Quality Control Plan for San Francisco Bay (CRWQCB, San Francisco Bay Region, 2007).

4. Criteria Continuous Concentration from California Toxics Rule (USEPA, 2000).

5. California Department of Health Services, Division of Drinking Water and Environmental Management. Title 22, California Code of Regulations Division 4. Environmental Health Chapter

15. Domestic Water Quality And Monitoring Article 4. Primary Standards — Maximum contaminant levels.

6. Waste Discharge Requirements for Stockton Deepwater Channel Maintenance Dredging. Order No. R5-2004-0061-001(CVRWQCB, 2016).

7. National Toxics Rule (1992).

J = Estimated value between the method detection limit and reporting limit

4.0 METHODS

Sediment sampling within the SBC took place on April 29 and 30, 2019. Sampling and testing were in accordance with the Suisun Bay Channel and New York Slough 2019 Project SAP and the 2014 Master SAP for O&M dredging.

4.1 Sampling and Testing Approach

The Project SAP summarizes the sampling and testing approach. In general, subsurface sediment samples for physical testing were collected with a vibracore sampler at 12 locations within the areas of the SBC with identified shoaling. Sampling locations in relation to the March 2019 bathymetric data are provided in Appendix A along with the target SAP locations. Table 6 summarizes the date and time of sampling, final sampling coordinates, and sampling elevations.

Except for two locations in the Bulls Head Reach (SNY-2019-1-1 and SNY-2019-1-2), each SBC core collected consisted of the material from the mudline to -37-feet MLLW, which is the authorized dredge depth plus two feet for overdepth allowance. The Bulls Head reach locations were sampled to the advanced maintenance dredging depth of -37 feet MLLW plus two feet for overdepth (-39 feet MLLW overall). A vertical composite sample for physical testing and two archive samples that represented the material from the mudline to two feet below the authorized dredge depths were collected from all cores. One archive sample collected from each location is being held frozen in case later chemical testing is requested. The second archive sample from each location is being held at 4º C as additional material for possible physical testing. Note that it was determined subsequent to sampling that the predicted tidal depths used to determine tidal stage, were two to four inches less than actual water depths according to data published in NOAA tides and currents website (SF Port section). Since visual observations showed that the sediment type below the overdepth elevations was physically similar to the material above, this deviation is considered minor.

4.2 Sampling Methods

This section discusses vibracore sampling, sample processing and documentation procedures.

Sampling methods were conducted in accordance with the Project and Master SAPs. Methods did not deviate from the SAPs unless indicated below.

4.2.1 Positioning and Depth Measurements

A Garmin GPSMAP B40XS differential GPS (DGPS) navigation system operating in Wide Area Augmentation System (WAAS) mode was used for positioning at the sampling locations.

Locations were recorded in both Geographic coordinates (NAD 83) and State Plane Coordinates (CA Zone VI, NAD 83). Water depths in feet MLLW were determined with a lead line and adjusted using NOAA tide prediction tables for Port Chicago and Pittsburg. All sampling sites were located within the Federal Channel limits and were close to target coordinates (Appendix A).

Table 6. Actual Sampling Locations, Core Depths, Mudline Elevations, and Sampling Elevations for the SBC Cores.

Core Designation

Date Sampled

Time Sampled

California Lambert Zone 3 (NAD 83)

Geographic Coordinates

(NAD 83)

Mudline Elevation

(ft., MLLW)*

Sampling Elevation

(ft., MLLW)

Core Recovery

(ft.)

Core Interval Sampled

(ft., MLLW) Northing (feet)

Easting (feet)

Latitude North

Longitude West

Sample Area 1 (SNY-2019-1)

SNY-2019-1-1 04/29/2019 13:45 1776608 6528433 38º 02.433' 122º 06.923' -37.4 -39 3.4 -37.4 to -39

SNY-2019-1-2 04/29/2019 14:20 1776790 6528745 38º 02.463' 122º 06.858' -37.3 -39 2.3 -37.3 to -39

SNY-2019-1-3 04/30/2019 08:35 1781331 6538595 38º 03.213' 122º 04.807' -34.8 -37 2.9 -34.8 to -37

SNY-2019-1-4 04/30/2019 09:20 1782047 6539680 38º 03.331' 122º 04.581' -34.7 -37 2.9 -34.7 to -37

Sample Area 2 (SNY-2019-2)

SNY-2019-2-1 04/30/2019 09:50 1783096 6541255 38º 03.504' 122º 04.253' -36.0 -37 2.8 -36.0 to -37

SNY-2019-2-2 04/30/2019 10:15 1784969 6544213 38º 03.813' 122º 03.637' -36.0 -37 4.3 -36.0 to -37

SNY-2019-2-3 04/30/2019 10:30 1785750 6547601 38º 03.942' 122º 02.931' -35.4 -37 3.8 -35.4 to -37

SNY-2019-2-4 04/30/2019 10:45 1785792 6548417 38º 03.949' 122º 02.761' -35.8 -37 3.0 -35.8 to -37

Sample Area 3 (SNY-2019-3)

SNY-2019-3-1 04/30/2019 11:00 1785488 6550241 38º 03.899' 122º 02.381 -35.6 -37 3.1 -35.6 to -37

SNY-2019-3-2 04/30/2019 11:30 1785700 6550390 38º 03.934' 122º 02.350' -35.0 -37 3.1 -35.0 to -37

SNY-2019-3-3 04/30/2019 12:30 1775753 6595981 38º 02.292' 121º 52.852' -35.6 -37 2.7 -35.6 to -37

SNY-2019-3-4 04/30/2019 13:00 1774009 6599013 38º 02.004' 121º 52.221' -35.2 -37 3.2 -35.2 to -37

4.2.2 Vibracore Sampling Methods

An electric vibracore was used to sample the SBC sediments. The vibracore consists of a 4-inch diameter aluminum coring tube, a stainless steel cutting tip, and a stainless-steel core catcher.

Inserted into the core tubes were food-grade clean polyethylene liners. Use of these liners was a deviation from the Master SAP, which called for polycarbonate or Lexan liners. The vibrating unit has two counter-rotating motors encased in a waterproof aluminum housing. A three-phase, 240-volt generator powers the motors.

Vibracore sampling was conducted from the 30-foot vessel RV Prophesy. This vessel was fully equipped with all necessary navigation, safety, and lifesaving devices per Coast Guard requirements. The RV Prophesy held station with two-point anchoring during vibracore deployment and retrieval. A 17-foot Boston Whaler was used to assist the RV Prophesy during anchoring. An on board A-frame and winch were used to lower and retrieve the vibracore head and tube.

All cores were advanced beyond the target sampling elevation (project elevation plus two feet for overdepth allowance). When penetration of the vibracore was complete, power was shut off to the vibra-head, and the vibracore was brought aboard the vessel. A check valve located on top of the core tube reduces or prevents sediment loss during pullout. The core tube was then detached from the vibra-head, and the core-cutting tip and catcher were removed. Afterwards, the core liners were removed and sealed on both ends.

4.2.3 Core Processing

Cores were processed on the same day aboard the RV Prophesy. Cores were placed in a PVC core rack that was thoroughly rinsed between cores. After placement in the core rack, core liners were split lengthwise to expose the recovered sediment. Once exposed, sediment that came in contact with the core liner was removed by scraping with a spoon. This step is necessary to remove any material that may have been carried along by the core liner. Each core was then photographed, measured, and lithologically logged. Core photographs are provided in Appendix B.

Following logging, vertical composite subsamples for archiving and horizontal composite formation were then formed by combining and homogenizing a representative sample from the mudline to the authorized overdepth in a pre-cleaned stainless-steel tray. A 0.5-liter portion of each vertical composite subsample for chemical archiving was placed in a pre-cleaned and certified glass jar with a Teflon®-lined lid. Additional material from each core was placed in polyethylene bags for the geotechnical archives. An additional representative portion of each vertical composite subsample was placed in a large pre-cleaned mixing bowl for area compositing with all other cores from an area. These composited sediments were placed in polyethylene bags for grain size analyses and a 500 ml glass jar for organic carbon content and moisture content.

For the preservation of all samples, filled containers were placed on ice immediately following sampling and maintained at 2 to 4°C until analyzed. Archived samples for chemistry were placed on ice initially and then frozen as soon as possible. Archived samples for physical testing are being kept refrigerated and maintained at 2 to 4° C. The sample containers, both jars and bags, were sealed to prevent any moisture loss and possible contamination.

4.2.4 Documentation and Sample Custody

Sample location, date, time and appropriate identification were physically marked on all sample containers, and all samples were handled under Chain of Custody (COC) protocols beginning at the time of collection. Redundant sampling data was also recorded on field data log sheets. Copies of the field data logs are included as Appendix C.

Samples were considered to be “in custody” if they are (1) in the custodian’s possession or view,

(2) in a secured place (locked) with restricted access, or (3) in a secure container. Standard COC procedures were used for all samples collected, transferred, and analyzed as part of this project.

The COC form was used to identify the samples, custodians, and dates of transfer. Copies of the COCs are included with the laboratory reports.

4.3 Laboratory Testing Methods

Grain size was determined by sieve according to ASTM D 6913 (2004). This method is similar to ASTM D 422 (1963) specified in the Project SAP but without hydrometer analysis to determine the silt and clay fractions. Required U.S. standard sieve sizes included No. 4, 7, 10, 14, 18, 25, 35, 45, 60, 80, 120, 170, 200, and 230 sieves.

EPA Method 9060A was used to measure the total organic carbon content. The method detection limits (MDLs) achieved ranged from 0.025 to 0.027% dry weight. The reporting limits (RLs) achieved ranged from 0.071 to 0.077% dry weight, which were less than the Master SAP stipulated RL of 0.1%.

SM 2540 B was used to determine percent solids. SM 2540 B determines the solids content by drying at 103-105º C. The MDL and RL achieved was the same as stipulated in the Master SAP at 0.1%.

5.0 RESULTS AND DISCUSSION

Physical testing results of the SBC sediments are summarized in Tables 7 and 8 below. Appendix D provides grain size data supplied by Hushmand Associates including grain size distribution plots. Appendix E contains the organic content and moisture content laboratory report from Eurofins Calscience.

5.1 Sediment Observations

Observed sediment characteristics were similar among cores. According to field logs (Appendix C), sediments from all cores were described as poorly graded sand (SP) or poorly graded sand with silt (SP-SM). Sediments were also mostly described as medium-grained sand with trace fines, and olive brown or dark brown in color.

5.2 Sediment Solids and Organic Carbon Content Results

Percentages of solid material and organic matter for each core sample are summarized in Table 7.

The solids content among composite samples ranged from 65.1% to 70.0%. The total organic carbon content among composite samples was low and similar to the 2009 and 2014 samples at 900 to 3,300 mg/kg (0.09 to 0.33%). Organic matter is an important source of food for benthic fauna. However, high organic matter content can reduce oxygen and cause the buildup of toxic by-products such as ammonia and sulfides. Levels in the SBC sediments are much lower than 3.5%, which is the critical point concentration Hyland et. al. (2005) suggests could lead to reduced species richness.

Table 7. 2019 SBC Composite Sediment Total Organic Carbon Content and Percent

Solids Data.

Analysis SBC Composite Samples (SNY-2019-)

1 2 3

% Solids 70.0 65.1 69.8

TOC (% dry) 0.32 0.33 0.09

5.3 Sediment Grain Size Results

Grain size (sieve) analyses were performed on each composite sample. Table 8 provides a summary of grain size results as percent passing through each sieve. The sand and gravel content (94.6% to 99.2%) is defined as 100 minus the percent passing through the #200 sieve and was well above the 80% threshold for more rigorous testing. The sand and gravel content is similar to the sand content in 2009 and higher than the sand content determined in 2014.

Table 8. 2019 SBC Composite Sample Sieve Analysis Data.

Composite Designation

Gravel Coarse Sand Medium Sand Fine Sand Silt/Clay

Gravel

% Sand % Fines2 Classification Sieve No. / Sieve Size / % Passing

3/41 3/8 4 7 10 14 18 25 35 45 60 80 120 170 200 230

19 mm 9.5mm 4.75mm 2.80mm 2.00mm 1.40mm 1.00mm 0.71mm 0.50mm 0.355mm 0.25mm 0.18mm 0.125mm 0.09mm 0.075mm 0.063mm

SNY-2019-1 100.0 100.0 99.7 99.4 99.2 99.0 98.7 98.1 96.3 84.0 35.5 9.7 1.7 0.9 0.8 0.7 0.3 99.0 0.8 POORLY GRADED SAND (SP)

SNY-2019-2 100.0 100.0 99.8 99.7 99.6 99.4 99.1 98.8 98.2 95.6 74.8 41.5 12.0 6.1 5.4 5.0 0.2 94.5 5.4

POORLY GRADED SAND WITH

SILT (SP-SM)

SNY-2019-3 100.0 99.8 99.7 99.6 99.5 99.2 97.9 93.0 84.8 71.5 46.3 16.9 3.9 1.9 1.7 1.6 0.3 98.0 1.7 POORLY GRADED SAND (SP)

1100% passed through sieve sizes greater than 3/4-inch.

2Percent fines based on passing through the #200 Sieve.

5.4 Analytical QA/QC

Analytical chemistry QC is formalized by EPA and State Certification agencies, and involves internal quality control checks for precision and accuracy. QA/QC findings presented are based on the validation of the data according to the quality assurance objectives detailed in the Master SAP and using guidance from EPA National Functional Guidelines for inorganic data review (USEPA, 2017a).

As the first step in the validation process, chemical analyses were checked to see if they were completed within EPA recommended holding times and the results were carefully reviewed to check that the laboratories met project RLs. All analyses were completed within USEPA specified holding times and Master SAP RLs were met.

QA/QC records (7 total) for the percent solids and TOC analyses included method blanks, laboratory duplicates, laboratory control samples and their duplicates (LCS/LCSDs) and matrix spikes and matrix spike duplicates (MS/MSDs). Total numbers of QC records by type are summarized in Table 9. No sediment results were qualified as a result of the QC review with all results being within acceptable QC limits. Overall evaluation of the analytical QA/QC data indicates that the chemical data are within established performance criteria and can be used for characterization of sediments in the SBC project areas.

Table 9. Counts of QC records per Chemical Category.

Analyte Group Blank Lab Dup LCS/LCSD MS/MSD Total

Sediment

Conventionals Percent Solids 1 1 2 Total Organic Carbon 1 2 2 5 Sediment Totals 2 1 2 2 7

Notes:

“DUP” = Duplicate “LCS” = Laboratory Control Sample “MS” = Matrix Spike

6.0 CONCLUSIONS

The results of this study confirm that the 2019 SBC sediments are similar in grain size characteristics to those determined in previous years with greater than 80% sand content.

Therefore, it is reasonable to assume that chemical concentrations in the sediments are similarly low to concentrations determined historically. As such, the SBC sediments are suitable for continual in-bay placement at SF-16 and/or SF-9. The sediments are also suitable for beneficial reuse at upland sites, which are in need of sand.

7.0 REFERENCES CITED

ADH Environmental. 2009. Suisun Bay Channel and New York Slough 2009 Maintenance

Dredging Sampling and Analysis Report FINAL. July 2009.

ASTM D 422-63. 2007. Particle-Size Analysis of Soils, American Society for Testing and Materials, W. Conshohocken, PA, 2007 revised edition.

ASTM D 6913. 2017. Standard Test Methods for Particle-Size Distribution (Gradation) of Soils Using Sieve Analysis, American Society for Testing and Materials, W. Conshohocken, PA, 2017 revised edition.

CVRWQCB. 2016. Waste Discharge Requirements for the Stockton Deepwater Ship Channel Maintenance Dredging. Activities for Mile 4.4 to 41.0. ORDER R5-2004-0061-001.

Updated August 2016.

ECM Inc, 2014; - Suisun Bay Channel and New York Slough 2014 Maintenance Dredging Sampling and Analysis Report. Environmental Cost Management, Inc., 2014. September 2014.

Hyland, J.L., L. Balthis, I. Karakassis, A. Petrov, J. Shine, O. Vestergaard and R. Warwick. 2005.

Orgainc Carbon Content of Sediments as an Indicator of Stress in the Marine Benthos.

Mar. Eco. Prog. Ser. Vol. 295:91-103, 2005.

SFBRWQCB. 2007. San Francisco Bay Basin (Region 2) Water Quality Control Plan (Basin Plan).

California Regional Water Quality Control Board, San Francisco Bay Region. Updated January 18, 2017.

USACE, San Francisco District. 2014. Master Sampling and Analysis Plan. USACE SF-District O&M Dredging. Prepared by USACE SF-District. February 2014.

USACE SF-District. 2019. Suisun Bay Channel and New York Slough, 2019 Maintenance Dredging Sampling and Analysis Plan (SAP). USACE SF-District. March 2019.

USEPA/USACE. 1998. Evaluation of Dredged Material Proposed For Discharge In Waters Of The U.S. – Testing Manual [Inland Testing Manual (Gold Book)]. EPA-823-B-98-004.

USEPA. 2000. Water Quality Standards: Establishment of Numeric Criteria for Priority Toxic Pollutants for the State of California (California Toxics Rule). 40 CFR 131.38. Federal Register Vol. 65, No. 97. May 18, 2000 .