sampling and analysis report - water.ca.gov · 1.2 project summary ... 5.3 assessment of sediment...

SAMPLING AND ANALYSIS REPORT

EVALUATION OF MINER SLOUGH SPUR CHANNEL DREDGE MATERIAL

PROSPECT ISLAND TIDAL HABITAT RESTORATION PROJECT

Prepared for:

STATE OF CALIFORNIA DEPARTMENT OF WATER RESOURCES

Prepared by:

KINNETIC LABORATORIES, INC. 307 WASHINGTON STREET SANTA CRUZ, CALIFORNIA

June 2016

i




Kinnetic Laboratories, Inc.

June 2016

Table of Contents Page Nos.

1.0 INTRODUCTION............................................................................................................... 1 1.1 Site Location and Configuration ................................................................................................ 1 1.2 Project Summary .......................................................................................................................... 4 1.3 Purpose and Approach ................................................................................................................ 4

2.0 PROJECT ORGANIZATION ........................................................................................... 5 2.1 Project Team and Responsibilities ............................................................................................ 5 2.2 Data Users ..................................................................................................................................... 6

3.0 METHODS .......................................................................................................................... 7 3.1 Study Design ................................................................................................................................ 7 3.2 Evaluation Criteria and Assessment of Potential Impacts .................................................... 22 3.3 Field Sampling Protocols .......................................................................................................... 23

3.3.1 Vessel Positioning and Depth Measurements ........................................................... 23 3.3.2 Vibracore Sampling Methods ................................................................................... 24 3.3.3 Turbidity Monitoring ................................................................................................ 24 3.3.4 Core Processing ........................................................................................................ 25 3.3.4 Equipment Decontamination .................................................................................... 26 3.3.5 Reference Site (Dredge Material Placement Area) Sampling .................................. 26 3.3.6 Water Sampling ........................................................................................................ 26 3.3.7 Documentation and Sample Custody ........................................................................ 26

3.4 Laboratory Testing Methods ................................................................................................... 27 3.4.1 Bulk Sediment Chemical Analyses ........................................................................... 27 3.4.2 Elutriate Testing ........................................................................................................ 27 3.4.3 DI-WET Testing ....................................................................................................... 28 3.4.4 Acute Toxicity Testing ............................................................................................. 28

4.0 RESULTS .......................................................................................................................... 29 4.1 Sediment Physical and Chemical Results ............................................................................... 29 4.2 SET Chemical and DI-WET Chemistry Results ................................................................... 29 4.3 Solid Phase Bioassay Results ................................................................................................... 29 4.4 Suspended Particulate Phase (SPP) Bioassay Results .......................................................... 30

5.0 DISCUSSION .................................................................................................................... 44 5.1 Sediment Observations ............................................................................................................. 44 5.2 Sediment Grain Size Characteristics ....................................................................................... 44 5.3 Assessment of Sediment Acid Neutralization Potential to Acid Generation Potential and

Sediment pH ............................................................................................................................... 44

ii

5.4 Cation Exchange Capacity ........................................................................................................ 44 5.5 Miner Slough Channel Sediment Pollutant Chemical Analyses ......................................... 45

5.5.1 Comparisons to Published Toxicity Effects Data ..................................................... 45 5.5.2 Comparisons to DDRS Screening Values................................................................. 46 5.5.3 Overall Comparisons to Prospect Island Placement Area Soil Concentrations ........ 47

5.6 DI-WET Chemical Analyses .................................................................................................... 47 5.7 Sediment Solid Phase Bioassay Testing ................................................................................. 47 5.8 SET/SPP Chemical Analyses and Bioassay Testing ............................................................. 48

5.9 Conclusions ........................................................................................................................ 48 6.0 QUALITY ASSURANCE/QUALITY CONTROL (QA/QC) ....................................... 50

6.1 Field Sampling Quality Management ..................................................................................... 50 6.2 Chemical Analyses Quality Management .............................................................................. 50

APPENDICES

APPENDIX A Field Data Logs APPENDIX B Core Photographs APPENDIX C Analytical Laboratory Reports APPENDIX D Bioassay Report APPENDIX E Analytical Laboratory Quality Assurance/Quality Control Report

List of Figures Page Nos.

Figure 1. Location of the Prospect Island Tidal Habitat Restoration Project. .............................. 2 Figure 2. Prospect Island Site Elevations and Potential Restoration Features. ............................ 3 Figure 3. Dredge Area Sampling Locations and the Most Recent Bathymetric Data. ................. 9

iii

List of Tables Page Nos.

Table 1. Project Team and Responsibilities. ................................................................................5 Table 2. Actual Sampling Locations, Core Depths, Mudline Elevations, and Sampling

Elevations for the Miner slough Spur Channel. ...........................................................12 Table 3. Analytical Methods and Target Quantitation Limits Achieved for the Sediment

Samples. .......................................................................................................................15 Table 4. Analytical Methods and Quantitation Limits Achieved for Elutriate and

Background Water Samples. ........................................................................................18 Table 5. Analytical Methods and Quantification Limits for the DI-WET Analyses. ................21 Table 6. Miner Slough Spur Channel 2015 Sediment Chemistry Results. ................................31 Table 7. Standard Elutriate and Background Water Results for Miners Slough 2015. .............35 Table 8. DI-WET Results for Miners Slough 2015. ..................................................................40 Table 9. Hyalella azteca Survival in the Miners Slough Spur Channel Sediments. ..................42 Table 10. Chironomus dilutus Survival in the Miners Slough Spur Channel Sediments. ...........42 Table 11. Replicate and Mean Survival Results and Median Lethal Concentrations for the

96-Hour Acute Standard Elutriate Suspended Particulate-Phase Toxicity Tests Using Fathead Minnows. .............................................................................................43

Table 12. Quality Control Summary for Field Sediment Sampling. ...........................................50 Table 13. Counts of QC records per Chemical Category. ...........................................................52 Table 14. Final QC Qualification Applied to Sample Results. ....................................................53

iv

LIST OF ACRONYMS ASTM American Society for Testing and Materials MSD Matrix Spike Duplicate

BLK Method or Procedural Blank ML Minimum Levels

BMP Best Management Practice NAD North American Datum

BS Blank Spike NP:AGP Neutralization potential/acid generation potential

BSD Blank Spike Duplicate NAVD North American Vertical Datum

CALFED California and Federal ND Not Detected

CD Compact Disc NOAA National Oceanic and Atmospheric Administration

CDFW California Department of Fish & Wildlife OEHA Office if Environmental Hazard Assessment

CEC Cation Exchange Capacity PAH Polyaromatic Hydrocarbon

CEQUA California Environmental Quality Act PCB Polychlorinated Biphenyl

CESPD Corps of Engineers South Pacific Division PDS Post Digestion Spike

CHHSL California Human Health screening Level PDSD Post Digestion Spike Duplicate

COC Chain of Custody PEC Probable Effects Concentration

CSLC California State Lands Commission PEL Probable Effects Level

CTR California Toxics Rule PPB Parts Per Billion

CV Coefficient of Variation PVC Polyvinyl Chloride

CVRWQCB Regional Water Quality Control Board, Central Valley Region

QA Quality Assurance

CVP Central Valley Project QC Quality Control

cy Cubic Yards QUAL Qualifier

DDD Dichlorodiphenyldichloroethane RBC Risk-Based Concentration

DDRS Delta Dredging and Reuse Strategy Report RL Reporting Limit

DDE Dichlorodiphenyldichloroethylene RPA Reasonable and Prudent Alternative

DDT Dichlorodiphenyltrichloroethane RPD Relative Percent Difference

DGPS Differential Global Positioning Satellite SAP Sampling and Analysis Plan

DI-WET Deionized Water Waste Extraction Test SET Standard Elutriate Test

DTSC Department of Toxic Substances Control SOPs Standard Operating Procedures

DUP Laboratory Replicates SP Solid Phase

DWR California Department of Water Resources SPP Suspended Particulate Phase

EIR Environmental Impact Report SRM Standard Reference Material

FRPA Fish Restoration Program Agreement SQG Sediment Quality Guideline

GPS Global Positioning Satellite SQuiRT Sediment Quick Reference Tables

HDPE High-density Polyethylene STLC Title 22 Soluble Threshold Limit Concentration

ITM Inland Testing Manual SURR Surrogate Analysis

IWG Interagency Working Group SWQCB State Water Resources Control Board

LC50 Lethal Concentration Median SWP State Water Project

LCL Lower Control Limit TEC Threshold Effects Concentration

LCS Laboratory Control Spike TEL Threshold Effects Level

LDPE Low-density Polyethylene TOC Total Organic Carbon

LPC Limiting Permissible Concentrations TRPH Total Recoverable Hydrocarbons

LSD Least Significant Difference TTLC Title 22 Total Threshold Limit Concentration

LTMS Long Term Management Strategy UCL Upper Control Limit

MCL Maximum Contaminant Levels USFWS U.S. Fish and Wildlife Service

MDL Method Detection Limit USACE U.S. Army Corps of Engineers

MET Modified Elutriate Test USEPA U.S. Environmental Protection Agency

MS Matrix Spike USCS Unified Soil Classification System

v

EXCUTIVE SUMMARY The State of California Department of Water Resources (DWR) is planning to remove up to 53,500 cubic yards (cy) of sediments to deepen a spur channel off Miner Slough along the southern end of Prospect Island (Figures 1 through 3) from its current elevation of between -4 and -8 feet NAVD88 to an elevation of -16 feet NAVD88. The purpose of this deepening is to increase tidal flows from Miner Slough through a future breach of a levee located on the southern property of Prospect Island adjacent to the Spur Channel as well as through the levee between the Island’s southern and northern properties. Enhanced tidal flow is integral to the Prospect Island Tidal Habitat Restoration Project, which is a joint effort to restore fish habitat to a 1,600-acre restoration area. The plan is to place the dredged sediments from the Miner Slough Spur Channel within the restoration area where it would be graded to provide intertidal and upland habitat. All excess water would be allowed to evaporate on site. Dredging would occur prior to breaching the restoration site. The purpose of this sampling and testing program was to determine environmental suitability for dredging and placement of dredged sediments on Prospect Island. Evaluations were focused on sediment and elutriate chemistry, acute toxicity characteristics, and on the potential leaching of contaminants from dredge material after placement. Chemical data derived from the testing of the dredge material were compared to chemical data derived from background soil sampled and tested in the proposed placement area as well as to sediment quality benchmarks established by the CVRWQCB and other State and federal agencies. Ideally, the dredge material has chemical concentrations that are at or below the concentrations found in the background soil. This approach avoids any degradation of soils at the dredge material placement site. Toxicity data for the project were compared to applicable reference and control data, and elutriate and leachate data were compared to applicable water quality criteria. The dredge area was divided into five composite areas for testing as shown in Figure 3. Vibratory core samples were collected from two locations within each composite area. Representative (equally weighted) material from both locations within a composite area were combined into a composite sample for testing. Vertically continuous samples were collected from the mudline down to the Proposed Project design dredging elevation of -16 ft NAVD88 plus two feet for overdepth allowance (-18 ft NAVD88 total) or to the elevation of sampler refusal. These samples were archived as well as used to form the area composite samples. If refusal did not occur, additional archive samples were collected from the one foot of material (-18 to -19 ft NAV88) below the overdepth elevation at each location that represents the material to be left in place after dredging (Z-layer). In addition, six surface sediment samples (top 0.5 feet) were collected within the Prospect Island South Property dredge material placement area (Figure 3) to characterize the placement/reuse area as reference material. Sediments from these six samples were combined into two composite samples for testing. Bulk sediments from the dredge and reference area composite samples were subjected to physical and chemical analysis for contaminants of concern. Analyses included grain size distribution, total organic carbon (TOC), percent solids, trace elements (Al, Sb, As, Ba, Be, B, Cd, Co, Cr, Cu, Hg,

vi

Mn, Mo, Pb, Ni, Se, Ag, Ti, V, and Zn), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), butyltins, hexavalent chromium, ammonia, organochlorine pesticides and organophosphate pesticides. In addition, the dredge sediment and reference composite samples were analyzed for acid generation/neutralization potential (NP:AGP ratio) and cation exchange capacity (CEC). A Standard Elutriate Test (SET) was also conducted on the five dredge material composite samples to conservatively simulate the action of the clamshell dredge that might cause mobilization of contaminants during the dredging process. The SET extracts were analyzed for much of the same list of constituents analyzed in the sediment samples. The results of the SET were compared to water quality goals and background water concentrations. In addition, the SET extracts underwent multiple-dilution acute toxicity testing using fathead minnows (Pimephales promelas). The toxicity test data from the dredge area composite samples were statistically compared to the toxicity data from tests carried out on a sample of background water. The possibility exists that reused sediments from the Miner Slough Spur Channel will be exposed to benthic organisms once Prospect Island has been restored to a freshwater tidal habitat. Therefore, 10-day toxicity testing was conducted according to Inland Testing Manual (ITM) recommendations. Benthic species used for this Project were the freshwater amphipod Hyalella Azteca and the freshwater midge Chironomus dilutus. Some sediment concentrations in the Miner Slough Spur Channel composite samples exceeded sediment screening values for adverse biological effects to benthic organisms as well as to screening values for terrestrial plants and animals. However, the sediments were not toxic to benthic organisms, and references concentrations, for the most part, exceeded the same objectives. Therefore, there is little evidence that the Miner Slough Spur Channel sediments, from a non-water quality aspect, will degrade the soils already present on Prospect Island within the placement area. DI-WET analyses suggest that leachate impacts to surface waters or groundwater could be problematic. Water quality goals, especially dredge material reuse limits listed in draft Regional Board Waste Discharge Requirements (WDRs) for medium sized dredge projects, were exceeded for several metals, especially for aluminum and manganese. Site-specific natural attenuation factors may need to be assessed to determine the significance of these exceedances. Results do show that the sediments have a high neutralization potential and a sufficient CEC to aid in attenuation. Standard elutriate testing did show also that water quality objectives could be exceeded directly at the dredge site with no dilution for aluminum, barium and manganese in all areas and zinc in one area. However, it would only take a dilution factor of about six to bring all concentrations to below water quality objectives and the concentrations in the SET extracts most likely overestimate concentrations at the dredge site. Also, there was no evidence of toxicity to Fathead Minnows in the standard elutriate samples. Therefore, water quality impacts during dredging operations are predicted to be minimal and any concerns could be mitigated by the use of Best Management Practices such as the use of silt screens during dredging.

1




Kinnetic Laboratories, Inc.

June 2016

1.0 INTRODUCTION The Prospect Island Tidal Habitat Restoration Project (Project) is a joint effort by the California Department of Water Resources (DWR) and the California Department of Fish & Wildlife (CDFW) under the Fish Restoration Program Agreement (FRPA). FRPA implements the fish habitat restoration actions to fulfill the 8,000‐acre tidal restoration obligations of DWR, contained within the Reasonable and Prudent Alternative (RPA) of the U.S. Fish and Wildlife Service Delta Smelt Biological Opinion (USFWS, 2008), referenced in the National Marine Fisheries Service Salmonid Biological Opinion (NMFS, 2009) for long‐term coordinated operations of the State Water Project (SWP) and the federal Central Valley Project (CVP), as well as the CDFW (2009) Incidental Take Permit for SWP Delta operations. The Project is consistent with DWR’s Environmental Stewardship Policy, which states that DWR has a responsibility to protect and restore the environment and should implement projects that contribute to the recovery of listed species. In public comments on the May 17, 2013 Notice of Preparation of a draft Environmental Impact Report (EIR), concerns were raised over sediment quality on Prospect Island and the potential for release of mercury/methylmercury and other toxins from Project activities into waterways and onto state lands underlying those waterways. DWR is currently preparing an EIR for the Project in compliance with the California Environmental Quality Act (CEQA) (Public Resources Code Section 21000 et seq.) and the CEQA Guidelines (California Code of Regulations Title 14, Chapter 3, Sections 15000‐15387), as amended. DWR is the lead agency under CEQA. In accordance with CEQA, the lead agency is responsible for the scope, content, and legal adequacy of the document. The EIR will evaluate the environmental effects of implementing a plan to restore tidal action to Prospect Island for the benefit of native fish species. 1.1 Site Location and Configuration The Project area is on Prospect Island, located in the Sacramento-San Joaquin River Delta, approximately seven miles north of Rio Vista and eight miles west of Walnut Grove, between the Sacramento Deep Water Ship Channel and Miner Slough within Solano County (Figures 1 and 2). The island is bounded on the west by the Sacramento Deepwater Ship Channel and on the east by Miner Slough and a spur channel to Miner Slough. The Prospect Island Project area is approximately 1,600 acres in size. The island is divided into two major properties separated by an internal cross levee. The northern property, approximately 1,300 acres in size, is owned by DWR and the southern property, approximately 300 acres in size, was recently acquired by DWR from the Port of West Sacramento. Part of the south property is

2

bounded to the east by the Miner Slough Spur Channel. Site elevations and proposed restoration features within the Project areas are shown in Figure 2.

Figure 1. Location of the Prospect Island Tidal Habitat Restoration Project.

3

Figure 2. Prospect Island Site Elevations and Potential Restoration Features.

4

Northern Breach

Cross Levee Breach

Southern Breach

4

1.2 Project Summary Under the Proposed Project, the Miner Slough levee would be breached in two locations: one at the north property, approximately 0.5 miles south of Arrowhead Harbor, and one at the south property, at the location of the formerly repaired breach connecting to the Miner Slough Spur Channel. The internal cross levee separating the north and the south properties would also be breached. Once these breaches are completed, the north and south properties would be subject to daily tidal inundation. The levee breach locations are shown on Figure 2. Another component of the Proposed Project and the focus of this report would be to dredge the Miner Slough Spur Channel to ensure that unimpeded tidal exchange occurs through the southern breach to Miner Slough. Modeling results show that the current geometry of the Miner Sough Spur Channel is undersized for the anticipated volume of tidal exchange between Miner Slough and the restored Project site, and would therefore result in tidal dampening within the Project site. Deepening the Spur Channel from its current mudline elevations of between -4 and -8 ft NAVD88 to a Project elevation of -16 ft NAVD88 was modeled as a means of providing the necessary tidal exchange (DWR and CDFW 2014). This would result in dredging up to 53,600 cy of material from the Spur Channel. Of this volume, 47,000 cy is the estimated volume down to the Project elevation and 6,600 cy is the volume associated with a two foot overdepth allowance. Dredging of the Miner Slough Spur Channel would be accomplished by clamshell dredging methods. If the dredged material meets environmental screening criteria, it would be placed within the Project site at the area designated as E on Figure 2 where it would be graded to provide intertidal and upland habitat. The dredged material would be loaded into a barge and brought to an off-loading area at the Project site where it would likely be loaded into trucks for transport to the Prospect Island dredge material placement area (Figure 2). All excess water would be allowed to evaporate on site. Dredging would occur after the South Property levee is repaired and prior to breaching the Project site. 1.3 Purpose and Approach The purpose of this sampling and testing program is to determine the environmental suitability for dredging and placement of dredged sediments on Prospect Island. This Sampling and Analysis Report (SAR) discusses sampling and testing procedures, analytical and biological testing results, and quality assurance/quality control (QA/QC) results necessary to support a Section 404 permit and Section 401 water quality certification. Evaluations were focused on sediment and elutriate chemistry, acute toxicity characteristics, and on the potential leaching of contaminants from dredge material after placement. Chemical data derived from the testing of dredge material were compared to chemical data derived from background soil sampled and tested in the proposed placement area as well as to sediment quality benchmarks established by the CVRWQCB and other State agencies. Ideally, the dredge material has chemical concentrations that are at or below the concentrations found in the background soil. This approach avoids any degradation of soils at the dredge material placement site. Toxicity data derived were compared to applicable reference and control data, and elutriate and leachate data were compared to applicable water quality criteria.

5

2.0 PROJECT ORGANIZATION 2.1 Project Team and Responsibilities Kinnetic Laboratories (KLI) has been subcontracted by Cal-Neva Construction and Hultgrin-Tillis through contracts with DWR to provide the sediment and water sampling and analyses. The responsibilities for elements of this program are provided in Table 1. Key contacts for this sediment characterization program are as follow: Brent Lamkin Department of Water Resources 3500 Industrial Blvd. West Sacramento, CA 95691 Tel. (916) 376-9881 Fax. (925) 376-9917 [email protected]

Dan Riordan Department of Water Resources 3500 Industrial Blvd. West Sacramento, CA 95691 Tel. (916) 376-9738 Fax. (925) 376-9662 [email protected]

Ken Kronschnabl Kinnetic Laboratories, Inc. 307 Washington Street Santa Cruz, CA 95060 Tel. (831) 457-3950 Fax. (831) 426-0405 [email protected]

Table 1. Project Team and Responsibilities.

Responsibility Name Affiliation

Project Planning and Coordination Brent Lamkin

Dan Riordan

DWR

DWR

Sampling and Analysis Plan (SAP) Preparation Ken Kronschnabl KLI

Field Sample Collection and Transport Spencer Johnson KLI

Health and Safety Officer/ Site Safety Plan Jon Toal KLI

Laboratory Physical and Chemical Analyses Bob Stearns Calscience

Laboratory Toxicity Testing Jeff Cotsifas Pacific EcoRisk

QA/QC Management Amy Howk KLI

Technical Review Pat Kinney

Brent Lamkin

KLI

DWR

Final Report Ken Kronschnabl KLI

Agency Coordination Brent Lamkin

Ken Kronschnabl

DWR

KLI KLI = Kinnetic Laboratories, Inc. DWR = CA Department of Water Resources

6

2.2 Data Users Principal users of the data produced for this report are the following regulatory agencies:

1. Central Valley Regional Water Quality Control Board (CVRWQCB)—Region 5; 2. Sacramento District, U.S. Army Corps of Engineers (USACE); 3. U.S. Environmental Protection Agency (USEPA) - Region IX; and 4. California State Lands Commission (CSLC).

Other users of the data may include the following agencies:

1. CALFED Bay Delta Program; 2. U.S. Fish and Wildlife Service (USFWS); 3. California Department of Fish and Wildlife (CDFW); 4. National Marine Fisheries Service (NMFS); and 5. Interagency Working Group (IWG) of the Delta Long Term Management Strategy

(Delta LTMS)

7

3.0 METHODS The study design and methodologies used to characterize the Miner Slough Spur Channel dredge sediments as well as the proposed placement/reuse area are described below. The study design and methodologies used followed those detailed in the CVRWQCB approved Project SAP (Kinnetic Laboratories, 2015). 3.1 Study Design Sampling and testing of Miner Slough Spur Channel sediments was carried out with guidance from the Inland Testing Manual (ITM) (USEPA and USACE, 1998) and the Upland Testing Manual (USACE, 2003) with further guidance from the Delta Dredging and Reuse Strategy Report (DDRS)(CVRWQCB, 2002). Acceptability guidelines published in these documents were used to evaluate the suitability of placing the material within the proposed placement area identified as Component E in Figure 2. Figure 3 defines the limits of dredging within the Miner Slough Spur Channel as well as the limits of the Prospect Island South Property dredge material placement area. Dredge area bathymetric contour lines are also provided on Figure 3. Three cross-sections of the dredge area depicting both current bottom (mudline) and proposed mudline elevations are shown on Figure 4. The dredge area was divided into roughly five composite areas for testing as shown on Figure 3. Vibratory core samples were collected from two locations within each composite area. Representative (equally weighted) material from both locations within a composite area were combined into a composite sample for testing. Final sampling locations are shown on Figure 3. Date and time of sampling, location coordinates, approximate mudline elevations, and core intervals sampled are listed in Table 2. Vertically continuous samples were collected from the mudline down to the Proposed Project design dredging elevation of -16 ft NAVD88 plus two feet for overdepth allowance (-18 ft NAVD88 total) or to the elevation that sampler refusal occurred. If refusal did not occur, additional archive samples were collected from the one foot of material below the overdepth elevation at each location that represents the material to be left in place after dredging (Z-layer). These archives as well as archives of the individual cores from the mudline to the overdepth elevation are being held frozen in case a need arises to perform additional chemical analyses. Six surface sediment samples (top 0.5 feet) were collected within the Prospect Island South Property dredge material placement area to characterize the placement/reuse area as reference material. Final sampling locations for these are shown on Figure 3 and location coordinates are listed in Table 2. The six South Property dredge material placement area reference samples were combined into two composite samples. As is with the dredge area samples, sediment from all individual reference area samples were archived frozen and are being held for up to a year for potential future analysis. .

8

Page Left Intentionally Blank

9

Figure 3. Dredge Area Sampling Locations and the Most Recent Bathymetric Data.

MSAVC14-A1

MSAVC14-A2

MSAVC14-B1

MSBVC14-C2

MSBVC14-D2

MSBVC14-E1

MSAVC14-C1

MSBVC14-E2

Composite Area B

Composite Area D

PI-REF-14-A1

PI-REF-14-B1

PI-REF-14-A2

PI-REF-14-A3

PI-REF-14-B3

MSAVC14-B-2

MSBVC14-D1

Composite Area A

Composite Area C

Composite Area E

PI-REF-14-B2

10

Page Left Intentionally Blank

11

Figure 4. Miner Slough Spur Channel Dredge Area Cross Sections.

HIGH TIDE LINE

12

Table 2. Actual Sampling Locations, Core Depths, Mudline Elevations, and Sampling Elevations for the Miner Slough Spur Channel.

Area Core

Designation Date Time

Geographic Coordinates (NAD 83)

California Lambert Zone 2 (NAD 1983) Mudline

Elevation1 (ft., NAVD88)

Sampling Elevation2

(ft., NAVD88)

Core Recovery

(ft.)

Core Intervals Sampled

(ft., NAVD88) Latitude North

Longitude West

Northing (ft)

Easting (ft)

A MSAVC15-A1 11/30/15 1605 38 14.460' 121 39.903' 1849765 6657872 -6.8 -19 11.3

-6.8 to -18 -18 to -18.1

MSAVC15-A2 11/30/15 1525 38 14.482' 121 39.934' 1849898 6657723 -3.6 -19 13.0 -3.6 to -16.6* No Z-Layer

B MSAVC15-B1 11/30/15 1440 38 14.512' 121 39.945' 1850080 6657665 -4.3 -19 15.0

-4.3 to -18 -18 to -19

MSAVC15-B2 11/30/15 1410 38 14.549' 121 39.965' 1850304 6657573 -5.8 -19 10.8 -5.8 to -16.6* No Z-Layer

C MSBVC15-C1 11/30/15 1336 38 14.572' 121 39.921' 1850445 6657783 -7.8 -19 9.9

-7.8 to -17.7* No Z-Layer

MSBVC15-C2 11/30/15 1305 38 14.594' 121 39.877' 1850579 6657993 -8.8 -19 7.0 -8.8 to -15.8* No Z-Layer

D MSBVC15-D1 11/30/15 1210 38 14.618' 121 39.844' 1850725 6658151 -8.0 -19 8.3

-8.0 to -16.3 -18 to -19

MSBVC15-D2 11/30/15 1140 38 14.645' 121 39.811' 1850893 6658321 -11.8 -19 7.1 -11.8 to -18 -18 to -18.5

E MSBVC15-E1 11/30/15 1020 38 14.674' 121 39.811' 1851065 6658307 -5.5 -19 10.0

-5.5 to -15.5* No Z-Layer

MSBVC15-E2 11/30/15 1055 38 14.662' 121 39.782' 1851024 6658446 -7.6 -19 9.1 -5.6 to -16.7* No Z-Layer

PIREF A

PI-REF-15-A1 12/07/15 1530 38 14.642' 121 39.657' 1850874 6659045 NA NA 0.5 0 – 0.5 bgs

PI-REF-15-A2 12/07/15 1510 38 14.697' 121 39.645' 1851208 6659101 NA NA 0.5 0 – 0.5 bgs

PI-REF-15-A3 12/07/15 1500 38 14.745' 121 39.663' 1851499 6659014 NA NA 0.5 0 – 0.5 bgs

PIREF B

PI-REF-15-B1 12/07/15 1410 38 14.675' 121 39.577' 1851076 6659427 NA NA 0.5 0 – 0.5 bgs

PI-REF-15-B2 12/07/15 1350 38 14.717' 121 39.587' 1851331 6659379 NA NA 0.5 0 – 0.5 bgs

PI-REF-15-B3 12/07/15 1330 38 14.767' 121 39.603' 1851634 6659301 NA NA 0.5 0 – 0.5 bgs NA = Not Applicable bgs = Below Ground Surface *Rejection Encountered 1. Approximate bottom elevation of Miner Slough Spur Channel 2. Target Sample Elevation is mudline to project/design elevation plus two feet for overdepth and plus one foot for the Z-Layer.

13

The exposure pathways for habitat restoration depend on the source of the dredge material and the type of habitat being created. At a minimum, the exposure pathways include the solid phase, leachate, effluent, plant uptake and animal uptake. With the exception of the effluent exposure pathway, testing and evaluation conducted on the Miner Slough Spur Channel sediments was aimed at addressing these exposure pathways. Dredge material fill activities on Prospect Island will not result in any effluent discharge to receiving waters. In addition, prolonged human exposure is not anticipated in relation to placement of the sediments within Prospect Island. Three potential issues from possible contaminants in the Miner Slough Spur Channel sediments were assessed. The first issue was determining the solid phase environmental suitability for placement on Prospect Island. Next, potential water quality impacts that could occur at the dredge site caused by the dredging activity was assessed. The third and final issue assessed was potential water quality impacts caused by leaching of contaminants to groundwater or receiving waters from the dredge material placement area. Bulk sediments from the dredge and reference area composite samples were subjected to physical and chemical analysis for contaminants of concern in the DDRS. Analyses conducted are listed in Table 3 and include grain size distribution, total organic carbon (TOC), percent solids, trace elements (Al, Sb, As, Ba, Be, B, Cd, Co, Cr, Cu, Hg, Mn, Mo, Pb, Ni, Se, Ag, Ti, V, and Zn), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), butyltins, hexavalent chromium, ammonia, organochlorine pesticides and organophosphate pesticides. In addition, the dredge sediment composite samples were analyzed for acid generation/neutralization potential (NP:AGP ratio) and cation exchange capacity (CEC). The NP:AGP ratio, discussed further below, is a measure of the degree of acid or base that will be generated by the sediment. CEC is the total capacity of a soil to hold and exchange cations. A Standard Elutriate Test (SET) was also conducted on the five dredge material composite samples to conservatively simulate the action of the clamshell dredge that might cause mobilization of contaminants during the dredging process. The SET extracts were analyzed for the list of constituents identified in Table 4. The results of the SET were compared to water quality goals and background water concentrations. In addition, the SET extracts underwent multiple-dilution acute toxicity testing using fathead minnows (Pimephales promelas). The toxicity test data from the dredge area composite samples were statistically compared to the toxicity data from tests carried out on a sample of background water and on negative laboratory controls. Since dredging will be conducted using mechanical means (e.g., clamshell) and release of decant water return to receiving waters is not anticipated for this Project, similar chemical analyses and toxicity testing were not carried out using a modified elutriate test (MET). The possibility exists that reused sediments from the Miner Slough Spur Channel will be exposed to benthic organisms once Prospect Island has been restored to a freshwater tidal habitat. Therefore, two species 10-day toxicity testing was conducted according to Inland Testing Manual (ITM) recommendations. Benthic species used for this Project were the freshwater amphipod Hyalella Azteca and the freshwater midge Chironomus dilutus. The neutralization potential to acid generation potential (NP:AGP) ratio was determined for the Miner Slough Spur Channel sediments to assist in the assessment of leaching potential from the dredge materials at the placement areas over time. The NP:AGP ratio is a measure of the degree

14

of acid or base that will be generated by a sediment. The NP:AGP ratio is calculated by dividing the neutralization potential in tons of CaCO3/1000 tons of material, by the acid generation potential in tons of CaCO3 needed to neutralize 1000 tons of material. A value of one indicates that acid generation and neutralization potentials are equal and that the soil is therefore likely to remain neutral. An NP:AGP ratio of at least two to three is desirable so that after leaching, enough neutralizing potential will remain to neutralize pH after the sediment oxidizes. Acidic sediments are more likely to leach trace metals over time, and in some cases, acidic soils may require ongoing mitigation and monitoring.

15

Table 3. Analytical Methods and Target Quantitation Limits Achieved for the Sediment Samples.

Analyte Method

Method Detection

Limits Achieved

Laboratory Reporting

Limits Achieved

Target Reporting

Limits

CONVENTIONALS Particle Size (%) ASTM D4464 (M) 0.01 0.01 0.01 Ammonia (mg/kg) SM 4500-NH3 B/C (M) 0.055 0.1 0.2 Percent Solids (%) Plumb 1981 or SM2540 B 0.1 0.1 0.1 pH (pH Units) EPA 9045D 0.01 0.01 0-14 Cation-Exchange Capacity (cmolc/kg)

EPA 9081 0.00395 0.0544

1.0

Acid Generation Potential (AGP) (t CaCO3/Kt)

EPA 600/2-78/054 0.31 3.1 0.1

Acid Neutralization Potential (NP) (t CACO3/Kt)

EPA 600/2-78/054 0.1 0.5 0.5

Sulfides-dissolved (mg/kg wet) EPA 376.2M 0.017 0.1 0.1 Sulfides-total (mg/kg) EPA 376.2M 0.084 0.1 0.1 Total Organic Carbon (%) EPA 9060A 0.017 0.050 0.05 Oil & Grease (mg/kg) EPA 1664A (M) HEM 7.9 10 10 TRPH (mg/kg) EPA 1664A (M) HEM-SGT 8.1 10 10 METALS (mg/kg) Aluminum EPA 6020 0.615 5.0 5.0 Antimony EPA 6020 0.039 0.5 0.5 Arsenic EPA 6020 0.087 0.1 0.1 Barium EPA 6020 0.042 0.1 0.1 Beryllium EPA 6020 0.077 0.5 0.5 Boron EPA 6020 9.8 25 25 Cadmium EPA 6020 0.057 0.1 0.1 Chromium VI EPA 7196A 0.0054 0.8 0.8 Total Chromium EPA 6020 0.062 0.1 0.1 Cobalt EPA 6020 0.036 0.1 0.1 Copper EPA 6020 0.042 0.1 0.1 Lead EPA 6020 0.066 0.1 0.1 Manganese EPA 6020 0.031 0.5 0.1 Mercury EPA 7471A 0.00587 0.02 0.02 Molybdenum EPA 6020 0.146 0.2 0.1 Nickel EPA 6020 0.051 0.1 0.1 Selenium EPA 6020 0.073 0.1 0.1 Silver EPA 6020 0.031 0.1 0.1 Thallium EPA 6020 0.028 0.1 0.1 Vanadium EPA 6020 0.065 1.0 1.0 Zinc EPA 6020 0.795 1.0 1.0 METHYL MERCURY (ng/g) EPA 1630 Mod/FGS-070 0.015 0.050 0.0503 ORGANICS-CHLORINATED PESTICIDES (µg/kg) 2,4' DDD EPA 8270C (SIM) 0.076 0.2 1.0 2,4' DDE EPA 8270C (SIM) 0.035 0.2 1.0 2,4' DDT EPA 8270C (SIM) 0.062 0.2 1.0 4,4' DDD EPA 8270C (SIM) 0.040 0.2 1.0 4,4' DDE EPA 8270C (SIM) 0.040 0.2 1.0 4,4' DDT EPA 8270C (SIM) 0.053 0.2 1.0 Total DDT EPA 8270C (SIM) -- 0.2 1.0

16

Table 3 Continued. Analytical Methods and Target Quantitation Limits Achieved for the Sediment Samples.

Analyte Method

Method Detection

Limits Achieved


Limits Achieved

Target Reporting

Limits

Aldrin EPA 8270C (SIM) 0.038 0.2 1.0 BHC-alpha EPA 8270C (SIM) 0.058 0.2 1.0 BHC-beta EPA 8270C (SIM) 0.067 0.2 1.0 BHC-delta EPA 8270C (SIM) 0.093 0.2 1.0 BHC-gamma (Lindane) EPA 8270C (SIM) 0.034 0.2 1.0 Chlordane-alpha EPA 8270C (SIM) 0.067 0.2 1.0 Chlordane-gamma EPA 8270C (SIM) 0.053 0.2 1.0 Oxychlordane EPA 8270C (SIM) 0.073 0.2 1.0 Total Chlordane EPA 8270C (SIM) -- 0.2 1.0 Cis-nonachlor EPA 8270C (SIM) 0.051 0.2 1.0 Dieldrin EPA 8270C (SIM) 0.11 0.2 1.0 Endosulfan sulfate EPA 8270C (SIM) 0.1 0.2 1.0 Endosulfan I EPA 8270C (SIM) 0.058 0.2 1.0 Endosulfan II EPA 8270C (SIM) 0.091 0.2 1.0 Endrin EPA 8270C (SIM) 0.057 0.2 1.0 Endrin aldehyde EPA 8270C (SIM) 0.099 0.2 1.0 Endrin ketone EPA 8270C (SIM) 0.055 0.2 1.0 Heptachlor EPA 8270C (SIM) 0.051 0.2 1.0 Heptachlor epoxide EPA 8270C (SIM) 0.044 0.2 1.0 Methoxychlor EPA 8270C (SIM) 0.067 0.2 1.0 Mirex EPA 8270C (SIM) 0.039 0.2 5.0 Toxaphene EPA 8270C (ECD) 9.0 20 10 trans-Nonachlor EPA 8270C (SIM) 0.043 0.2 1.0 ORGANICS-BUTYLTINS (µg/kg) Monbutyltin Krone et al., 1989 1.4 3.0 3.0 Dibutyltin Krone et al., 1989 0.73 3.0 3.0 Tributyltin Krone et al., 1989 1.5 3.0 3.0 Tetrabutyltin Krone et al., 1989 0.74 3.0 3.0 ORGANICS-PCBs (µg/kg) PCB Aroclors of: 1016, 1221, 1232, 1242, 1248, 1254 and 1260

EPA 8082 4.2 – 8.5 10

10

Total PCBs as sum of all Aroclors EPA 8082 -- 10 10 ORGANICS-POLYAROMATIC HYDROCARBONS (PAHs) (µg/kg) 1-Methylnaphthalene EPA 8270C (SIM) 4.0 10 10 1-Methylphenanthrene EPA 8270C (SIM) 1.2 10 10 2,3,5-Trimethylnaphthalene EPA 8270C (SIM) 1.6 10 10 2,6-Dimethylnaphthalene EPA 8270C (SIM) 1.7 10 10 2-Methylnaphthalene EPA 8270C (SIM) 4.6 10 10 Acenaphthene EPA 8270C (SIM) 4.7 10 10 Acenaphthylene EPA 8270C (SIM) 4.6 10 10 Anthracene EPA 8270C (SIM) 5.0 10 10 Benzo[a]anthracene EPA 8270C (SIM) 4.5 10 10 Benzo[a]pyrene EPA 8270C (SIM) 4.8 10 10 Benzo[b]fluoranthene EPA 8270C (SIM) 4.9 10 10 Benzo[e]pyrene EPA 8270C (SIM) 2.0 10 10 Benzo[g,h,i]perylene EPA 8270C (SIM) 4.9 10 10

17

Table 3 Continued. Analytical Methods and Target Quantitation Limits Achieved for the Sediment Samples.

Analyte Method

Method Detection

Limits Achieved


Limits Achieved

Target Reporting

Limits

Benzo[k]fluoranthene EPA 8270C (SIM) 4.8 10 10 Biphenyl EPA 8270C (SIM) 1.8 10 10 Chrysene EPA 8270C (SIM) 4.2 10 10 Dibenzo[a,h]anthracene EPA 8270C (SIM) 4.7 10 10 Dibenzothiophene EPA 8270C (SIM) 1.5 10 10 Fluoranthene EPA 8270C (SIM) 5.0 10 10 Fluorene EPA 8270C (SIM) 5.0 10 10 Indeno[1,2,3-c,d]pyrene EPA 8270C (SIM) 6.3 10 10 Naphthalene EPA 8270C (SIM) 4.2 10 10 Perylene EPA 8270C (SIM) 5.0 10 10 Phenanthrene EPA 8270C (SIM) 1.5 10 10 Pyrene EPA 8270C (SIM) 4.3 10 10 Total Low Weight PAHs EPA 8270C (SIM) -- 10 10 Total High Weight PAHs EPA 8270C (SIM) -- 10 10 Total Detectable PAHs EPA 8270C (SIM) -- 10 10 ORGANICS-ORGANOPHOSPHATE PESTICIDES (µg/kg) Bolstar (Sulprofos) EPA 8141A 0.0068 0.05 50 Chlorpyrifos EPA 8141A 0.0067 0.05 50 Dementon EPA 8141A 0.009 0.05 50 Diazinon EPA 8141A 0.0084 0.05 50 Dichlorvos EPA 8141A 0.0056 0.05 50 Ethoprop (Ethoprofos) EPA 8141A 0.0079 0.05 50 Fenchlorphos (Ronnel) EPA 8141A 0.0055 0.05 50 Fensulfothion EPA 8141A 0.0059 0.05 50 Fenthion EPA 8141A 0.0057 0.05 50 Merphos EPA 8141A 0.0078 0.05 50 Methyl Parathion EPA 8141A 0.0068 0.05 50 Mevinphos EPA 8141A 0.0063 0.05 50 Tetrachlorvinphos (Stirofos) EPA 8141A 0.03 0.2 200 Tokuthion (Prothiofos) EPA 8141A 0.0055 0.05 50 Trichloronate EPA 8141A 0.0055 0.05 50

18

Table 4. Analytical Methods and Quantitation Limits Achieved for Elutriate and Background Water Samples.

Analyte Method

Method Detection

Limits Achieved

Reporting Limits

Achieved

Target Reporting

Limits

CONVENTIONALS Ammonia/Ammonium (µg/L) EPA 350.1 0.009 0.05 0.05 Chloride (mg/L) EPA 300 0.12 0.5 1.0 Total Suspended Solids (mg/L) SM2540 D 0.87 1.0 1.0 Total Dissolved Solids (mg/L) SM 2540 C 0.83 1.0 1.0 pH (pH Units) EPA 150.1 0.01 0.01 0.01 COD (mg/L) EPA 410.4 3.0 5.0 20 BOD (mg/L) SM 5210 B 0.58 1.0 1.0 Hardness (mg/L) SM 2340 C 0.99 2.0 2.0 Oil & Grease (mg/L) EPA 1664A HEM 0.8 1.0 1.0 METALS (µg/L) Dissolved Aluminum EPA 200.8 3.31 50 50 Dissolved Arsenic EPA 200.8 0.386 1.0 1.0 Dissolved Barium EPA 200.8 0.099 1.0 1.0 Dissolved Beryllium EPA 200.8 0.290 1.0 1.0 Dissolved Boron EPA 200.8 6.76 50 50 Dissolved Cadmium EPA 200.8 0.128 1.0 1.0 Dissolve Cobalt EPA 200.8 0.092 1.0 1.0 Chromium VI EPA 7196A 0.004 0.02 0.8 Dissolved Total Chromium EPA 200.8 0.402 1.0 1.0 Dissolved Copper EPA 200.8 0.140 1.0 1.0 Dissolved Lead EPA 200.8 0.09 1.0 0.5 Dissolved Manganese EPA 200.8 0.139 1.0 1.0 Total Mercury EPA 1631E 0.00011 0.0005 0.0005 Dissolved Molybdenum EPA 200.8 0.127 1.0 1.0 Dissolved Nickel EPA 200.8 0.132 1.0 1.0 Total Selenium EPA 200.8 0.168 1.0 1.0 Dissolved Silver EPA 200.8 0.111 1.0 1.0 Dissolved Thallium EPA 200.8 0.101 1.0 1.0 Dissolved Vanadium EPA 200.8 0.149 1.0 1.0 Dissolved Zinc EPA 200.8 0.479 5.0 2.0 METHYL MERCURY (ng/L) EPA 1630/FGS-070 0.026 0.05 0.05 ORGANICS-CHLORINATED PESTICIDES (µg/L) 2,4' DDD EPA 8270C (SIM) 0.0005 0.002 0.002 2,4' DDE EPA 8270C (SIM) 0.0005 0.002 0.002 2,4' DDT EPA 8270C (SIM) 0.0006 0.002 0.002 4,4' DDD EPA 8270C (SIM) 0.0005 0.002 0.002 4,4' DDE EPA 8270C (SIM) 0.0007 0.002 0.002 4,4' DDT EPA 8270C (SIM) 0.0009 0.002 0.002 Total DDT EPA 8270C (SIM) -- 0.002 0.002 Aldrin EPA 8270C (SIM) 0.0007 0.002 0.002 BHC-alpha EPA 8270C (SIM) 0.0003 0.002 0.002 BHC-beta EPA 8270C (SIM) 0.0004 0.002 0.002 BHC-delta EPA 8270C (SIM) 0.0006 0.002 0.002 BHC-gamma (Lindane) EPA 8270C (SIM) 0.0007 0.002 0.002 Chlordane-alpha EPA 8270C (SIM) 0.0005 0.002 0.002

19

Table 4 Continued. Analytical Methods and Quantitation Limits Achieved for Elutriate and Background Water Samples.

Analyte Method

Method Detection

Limits Achieved

Reporting Limits

Achieved

Target Reporting

Limits

Chlordane-gamma EPA 8270C (SIM) 0.0007 0.002 0.002 Oxychlordane EPA 8270C (SIM) 0.0005 0.002 0.002 Total Chlordane EPA 8270C (SIM) -- 0.002 0.002 Dieldrin EPA 8270C (SIM) 0.0006 0.002 0.002 Endosulfan sulfate EPA 8270C (SIM) 0.0008 0.002 0.002 Endosulfan I EPA 8270C (SIM) 0.0007 0.002 0.002 Endosulfan II EPA 8270C (SIM) 0.0008 0.002 0.002 Endrin EPA 8270C (SIM) 0.0009 0.002 0.002 Endrin aldehyde EPA 8270C (SIM) 0.0008 0.002 0.002 Endrin ketone EPA 8270C (SIM) 0.0009 0.002 0.002 Heptachlor EPA 8270C (SIM) 0.0007 0.002 0.002 Heptachlor epoxide EPA 8270C (SIM) 0.0005 0.002 0.002 Methoxychlor EPA 8270C (SIM) 0.0007 0.002 0.002 Mirex EPA 8270C (SIM) 0.0005 0.002 0.002 Toxaphene EPA 8081A 0.045 0.12 0.063 trans-Nonachlor EPA 8270C (SIM) 0.0006 0.002 0.002 ORGANICS-BUTYLTINS (µg/L) Monbutyltin Krone et al., 1989 0.0023 0.0029 0.003 Dibutyltin Krone et al., 1989 0.0017 0.0029 0.003 Tributyltin Krone et al., 1989 0.0013 0.0029 0.003 Tetrabutyltin Krone et al., 1989 0.0019 0.0029 0.003 ORGANICS-PCBs (µg/L) PCB Aroclors of: 1016, 1221, 1232, 1242, 1248, 1254 and 1260

EPA 8082 0.061 – 0.14 0.49 0.5

Total PCBs as sum of all Aroclors

EPA 8082 -- 0.49 0.5

ORGANICS-PAHs (µg/L) 1-Methylnaphthalene EPA 8270C (SIM) 0.028 0.2 0.2 1-Methylphenanthrene EPA 8270C (SIM) 0.025 0.2 0.2 2,3,5-Trimethylnaphthalene EPA 8270C (SIM) 0.11 0.2 0.2 2,6-Dimethylnaphthalene EPA 8270C (SIM) 0.021 0.2 0.2 2-Methylnaphthalene EPA 8270C (SIM) 0.026 0.2 0.2 Acenaphthene EPA 8270C (SIM) 0.020 0.2 0.2 Acenaphthylene EPA 8270C (SIM) 0.017 0.2 0.2 Anthracene EPA 8270C (SIM) 0.033 0.2 0.2 Benzo[a]anthracene EPA 8270C (SIM) 0.023 0.2 0.2 Benzo[a]pyrene EPA 8270C (SIM) 0.023 0.2 0.2 Benzo[b]fluoranthene EPA 8270C (SIM) 0.024 0.2 0.2 Benzo[e]pyrene EPA 8270C (SIM) 0.01 0.2 0.2 Benzo[g,h,i]perylene EPA 8270C (SIM) 0.021 0.2 0.2 Benzo[k]fluoranthene EPA 8270C (SIM) 0.023 0.2 0.2 Biphenyl EPA 8270C (SIM) 0.014 0.2 0.2 Chrysene EPA 8270C (SIM) 0.018 0.2 0.2 Dibenzo[a,h]anthracene EPA 8270C (SIM) 0.026 0.2 0.2 Dibenzothiophene EPA 8270C (SIM) 0.053 0.2 0.2

20

Table 4 Continued. Analytical Methods and Quantitation Limits Achieved for Elutriate and Background Water Samples.

Analyte Method

Method Detection

Limits Achieved

Reporting Limits

Achieved

Target Reporting

Limits

Fluoranthene EPA 8270C (SIM) 0.027 0.2 0.2 Fluorene EPA 8270C (SIM) 0.024 0.2 0.2 Indeno[1,2,3-c,d]pyrene EPA 8270C (SIM) 0.021 0.2 0.2 Naphthalene EPA 8270C (SIM) 0.023 0.2 0.2 Perylene EPA 8270C (SIM) 0.024 0.2 0.2 Phenanthrene EPA 8270C (SIM) 0.030 0.2 0.2 Pyrene EPA 8270C (SIM) 0.025 0.2 0.2 Total Low Weight PAHs EPA 8270C (SIM) -- 0.2 0.2 Total High Weight PAHs EPA 8270C (SIM) -- 0.2 0.2 Total Detectable PAHs EPA 8270C (SIM) -- 0.2 0.2 ORGANICS- Organophosphate Pesticides (µg/L) Bolstar (Sulprofos) EPA 8141A 0.13 0.2 0.2 Chlorpyrifos EPA 8141A 0.059 0.2 0.2 Dementon EPA 8141A 0.081 0.2 0.2 Diazinon EPA 8141A 0.062 0.2 0.2 Dichlorvos EPA 8141A 0.18 0.2 0.2 Ethoprop (Ethoprofos) EPA 8141A 0.090 0.2 0.2 Fenchlorphos (Ronnel) EPA 8141A 0.094 0.2 0.2 Fensulfothion EPA 8141A 0.10 0.2 0.2 Fenthion EPA 8141A 0.087 0.2 0.2 Merphos EPA 8141A 0.10 0.2 0.2 Methyl Parathion EPA 8141A 0.085 0.2 0.2 Mevinphos EPA 8141A 0.083 0.2 0.2 Tetrachlorvinphos (Stirofos) EPA 8141A 0.45 0.79 0.8 Tokuthion (Prothiofos) EPA 8141A 0.096 0.2 0.2 Trichloronate EPA 8141A 0.10 0.2 0.2

21

The Deionized Water Waste Extraction test (DI-WET) was performed on the composite samples. The DI-WET is commonly used to predict long term leaching characteristics of sediments. The DI-WET employs a 48-hour leaching period in a tumbled flask, followed by filtration and chemical analysis of the water to test for soluble metals. The test was conducted to simulate possible leaching of the sediments at the Prospect Island dredge material placement site from subsequent precipitation. The DI-WET metal analyses conducted are listed in Table 5. Table 5. Analytical Methods and Quantification Limits for the DI-WET Analyses.

Analyte Method Method Detection Limits Achieved

Reporting Limits Achieved

Target Reporting Limits

Hardness (mg/L) SM 2340 C 0.99 2.0 2.0 pH EPA 9040B 0.01 0.01 0.01 Dissolved Organic Carbon (mg/L) EPA 415.1 0.5 0.5 1.0 Total Dissolved Solids (mg/L) SM 2540 C 0.87 1.0 - 10 1.0 Specific Conductance SM 2510B 0.5 100 - 1000 1.0 METALS (µg/L) Aluminum EPA 200.8 3.31 50 50 Antimony EPA 200.8 0.0995 1.0 1.0 Arsenic EPA 200.8 0.386 1.0 1.0 Barium EPA 200.8 0.0986 1.0 1.0 Beryllium EPA 200.8 0.290 1.0 1.0 Boron EPA 200.8 6.76 50 50 Cadmium EPA 200.8 0.128 1.0 1.0 Cobalt EPA 200.8 0.0919 1.0 1.0 Chromium VI EPA 7196A 4.0 20 0.8 Chromium EPA 200.8 0.402 1.0 1.0 Copper EPA 200.8 0.140 11.4 1.0 Lead EPA 200.8 0.0898 0.50 0.5 Manganese EPA 200.8 0.139 1.0 1.0 Mercury EPA 1631E 0.000113 0.0005 0.0005 Molybdenum EPA 200.8 0.127 1.0 1.0 Nickel EPA 200.8 0.132 1.0 1.0 Selenium EPA 200.8 0.168 1.0 1.0 Silver EPA 200.7 0.111 1.0 1.0 Thallium EPA 200.8 0.101 1.0 1.0 Vanadium EPA 200.8 0.149 1.0 1.0 Zinc EPA 200.8 0.479 2.0 2.0

Guidance for the beneficial reuse of dredged materials has been published in the DDRS report. This document provides a framework and guidance on criteria selection and data interpretation relevant to potential issues associated with the Proposed Project. This includes water quality effects at the dredge site as well as longer-term mobilization of dissolved metals into Delta receiving waters due to run-off from upland beneficial reuse areas.

22

3.2 Evaluation Criteria and Assessment of Potential Impacts Since the Miner Slough Spur Channel sediments would be reused to create both intertidal and upland elevations, terrestrial plants and animals as well as benthic organisms could be impacted by the dredged sediments. As such, levels of chemical contaminants in the sediments were evaluated for long-term impacts by comparing sediment contaminant concentration data with available sediment quality guidelines for terrestrial plants and animals and to soil background levels summarized in the DDRS, as well as to empirically derived toxicity effects data for benthic organisms described below. More importantly, Miner Slough Spur Channel sediment concentrations were compared to the Prospect Island reference concentrations to determine if the dredged sediments will contribute to degradation of existing conditions. Prolonged human exposure to the dredged sediments is not anticipated after reuse. Therefore, contaminant concentrations in the Miner Slough Spur Channel sediments were not compared to human health objectives in the DDRS nor those promulgated by the USEPA and Cal/EPA. Sediment data were compared to toxicity effects levels for freshwater aquatic organisms found in the National Oceanic and Atmospheric Association (NOAA) Screening Quick Reference Tables (Buchman, 2008) and in a paper by MacDonald et al. (2000). The NOAA Screening Quick Reference Tables (SQuiRTs) contain empirically derived Threshold Effects Levels (TELs) and Probable Effects Levels (PELs) for freshwater sediments. Based on toxic effects and no effects data sets, contaminant concentrations below TELs rarely cause adverse biological effects and contaminant concentrations above PELs frequently cause adverse biological effects. Because of the uncertainty associated with TELs, PELs and other SQGs, MacDonald et al., (2000) published consensus-based SQGs (Threshold Effects Concentrations and Probable Effects Concentrations or TECs and PECs for 28 common contaminants). TECs and PECs are based on the geometric mean between effects levels published by others and are synonymous to the effects definitions for TELs and PELs. Background concentrations derived from the DREDGE database developed by the California Department of Fish and Wildlife and summarized in the DDRS are mean concentrations of contaminants detected in bulk sediment samples previously collected by others in the Delta. These mean concentrations are grouped into marina, riverine and ship channel classifications. Because of the limited number of previously collected samples for some chemical constituents in riverine areas, mean sediment contaminant concentrations in all areas of the Delta grouped together were used for the comparisons. As mentioned previously, benthic toxicity effects were also ascertained directly through solid phase (SP or benthic) bioassays. Benthic bioassay results were statistically compared with bioassay results from reference sediments collected from the Prospect Island south property dredge material placement area and with control sediments. Guidelines for interpretation of benthic bioassay results are published in the ITM (USEPA and USACE, 1998). If survival responses in the test sediment are statistically significantly lower than those in the reference sediment and if the difference in mean survival between groups is greater than 10% (20% for amphipods), then the test sediment is considered to have the potential to significantly degrade the aquatic environment.

23

Suspended particulate phase (SPP) toxicity testing was evaluated with respect to Limiting Permissible Concentrations (LPC). Standard elutriates were prepared with Miner Slough site water. Concurrent bioassays were performed on 100%, 50%, 10%, 5% and 1% elutriate concentrations and laboratory control water. Results of the SPP bioassays were statistically compared with control and site water bioassays. Elutriate samples which produced significantly greater toxicity than control water were identified. Statistical calculations were also conducted to determine lethal point estimate 50th percentile (LC50) values through interpolations. Concentrations of chemical constituents in the elutriate extracts were compared to narrative and numerical water quality guidelines in the Water Quality Control Plan (Basin Plan) for the Sacramento and San Joaquin Rivers (CVRWQCB, 2015), and the California Toxics Rule (CTR) criteria for the protection of aquatic organisms (USEPA, 2000a), and surface water objectives in the DDRS. DI-WET extracts were compared to draft General Waste Discharge Requirements for Medium Scale Dredging Operations in the Sacramento-San Joaquin Delta (CVRWQCB, undated). These objectives are specific for levee reuse material. The DI-WET extracts were also compared to CTR criteria for the protection of aquatic organisms and to State of California drinking water standards consisting of Maximum Contaminant Levels (MCLs). Proposed methods for some organic analyses do not achieve reporting limits as low as CVRWQCB screening values. To address issues of reporting limits meeting water quality limits, the State Water Resources Control Board (SWRCB) has issued a Policy for Implementation of Toxics Standards (SWRCB, 2005). This policy document identifies Minimum Levels (MLs) for use in reporting and compliance determination purposes. The Project met these MLs. 3.3 Field Sampling Protocols Sediments were sampled at a total of ten locations within the Miner Slough Spur Channel as identified on Figure 3. Sampling took place on November 30, 2015 from the 32-foot workboat R/V Walter Marie. Surface material from an additional six locations (Figure 3) at the Prospect Island dredge material placement area were sampled as reference material. These samples were collected on December 7, 2015 from an airboat (DMS Hurricane). Table 2 provides final sampling location coordinates, core depths, existing mudline elevations, and elevations sampled. A couple locations changed from what was proposed in the SAP to avoid navigational obstructions caused by excessive vegetation. Enough material was collected from each testing and reference area location to perform all the required ITM Tier II and Tier III analyses including potential reruns and an archived sample from each core was retained for later testing, if needed. In addition to sediment, water was collected on December 7, 2015 from the center of the Spur Channel for use in the preparation of elutriate samples and for analysis of background water quality samples. 3.3.1 Vessel Positioning and Depth Measurements Positioning at sampling locations was accomplished using a differential GPS (DGPS) navigation system with horizontal positioning accuracies of 1 to 3 meters. Sampling locations were reported

24

in both Geographic coordinates (NAD 83) and State Plane Coordinates (CA Zone 2, NAD 83). Water depths were measured with a graduated lead line and corrected to NAVD 88. Real time tidal stage was determined using DWR’s Data Exchange Center (Miner Slough at 5 Points). These data were used to calculate the seafloor elevation/mudline for each site. All sampling sites were located within the dredge prism and all but one location was within 30 feet of target coordinates. Location E2 could not be reached due to obstructions (thick mat of Water Hyacinth). Actual locations are listed on Table 2 and on Figure 3. 3.3.2 Vibracore Sampling Methods All Miner Slough Spur Channel sediment samples were collected using electrically powered vibratory coring equipment (Vibracore) and advanced to the Project sampling elevation (-18 ft NAV88) or depth of refusal. The sampling elevation included the design dredging elevation and an additional two feet of overdepth. Refusal was encountered at six out of the ten locations because of the presence of stiff clay at depth. The depth of refusal was defined as the depth at which the average rate of penetration is less than 0.1 feet/minute for a two-minute period. At the conclusion of a successful vibracore, the core liner was removed and split open for inspection, logging, and sampling. Processing took place aboard the R/V Walter Marie. Kinnetic Laboratories’ vibracore consists of a 4-inch diameter aluminum coring tube, a stainless steel cutting tip, and a stainless-steel core catcher. New, clean, food-grade polyethylene liners were inserted into the core tubes prior to sampling. The vibrating unit has two counter-rotating motors encased in a waterproof, aluminum housing. A three-phase, 240-volt generator powers the motors. The vibracore head and tube were lowered overboard via an 18-foot A-frame and winch. The unit was then vibrated until it reached target sampling elevation or until the depth of refusal was reached. 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 or piston assembly located on top of the core tube reduced or prevented sediment loss during pullout. The length of sediment recovered was noted by measuring down the interior of the core tube to the top of the sediment. The core tube was then detached from the vibra-head, and the core cutting tip and catcher were removed. Afterward, the core liners were removed and sealed on both ends and processed directly on board the sampling vessel. 3.3.3 Turbidity Monitoring As part of the permit issued by California the Department of Fish and Wildlife (CDFW), turbidity monitoring was required prior to and during ebb conditions at two Miner Slough locations while sampling. One location was 100 feet upstream of the confluence to the Spur Channel and Miner Slough and one location was 300 feet downstream of the confluence. Samples were collected approximately mid-depth and midstream of the slough using a Hydrolab Quanta turbidity probe. The probe was calibrated prior to use using appropriate standards (100 and 1000 NTUs). Turbidity, temperature and salinity data were recorded on a log sheet. The log sheet was kept aboard the sampling vessel to be made available upon request.

25

3.3.4 Core Processing Whole cores were processed on deck. Cores were placed on a PVC core rack that was cleaned between cores. After placement in the core rack, core liners were split lengthwise to expose the recovered sediment. Once exposed, sediment that came into contact with the core liner was removed by scraping with a pre-cleaned stainless steel spoon. Each core was photographed, measured, and lithologically logged in accordance with the Unified Soil Classification System (USCS) as outlined in ASTM Standards D-2488 (2009). Field logs are provided in Appendix A. Photographs were taken of each core (each photograph covered a maximum two-foot interval), and of sampling equipment and procedures. These pictures are provided in Appendix B. Following logging, vertical composite subsamples were created from each core to represent material from the mudline elevation to the Proposed Project sampling elevation, including two feet overdepth. The vertical composite subsamples were formed by combining and homogenizing a representative sample from each core in a pre-cleaned stainless steel or Teflon®-coated tray. A 0.5-liter portion of each vertical composite subsample was placed in a pre-cleaned and certified glass jar with a Teflon®-lined lid for archived material in addition to a 0.5-liter portion of Z-layer material, when collected, placed in a separate certified jar for archival. These vertical composite subsamples were used to form area composite samples for testing. Archived samples were retained from each vertical composite subsample. Individual core archives are being kept at Kinnetic Laboratories’ Santa Cruz facility and may be analyzed to identify potential hotspots within a composite area or to determine the physical and chemical characteristics of the material to be left in place after dredging. Another length-weighted portion of each primary vertical composite subsample was placed in another pre-cleaned tray for area compositing with the other core from the same composite area. This composited material was placed in a 1-liter jar for most chemical analyses, an additional 1-liter glass jar for sulfide analyses, a 250 ml glass jar for neutralization potential and acid generation potential, and a 1-gallon Ziploc bag for grain size analysis. All jars were certified clean and supplied with Teflon®-lined lids. The remaining portion of each composite sample was placed in pre-cleaned 3.5-gallon buckets with new, food grade LDPE liners along with another length-weighted portion of the individual cores from each composite area. A minimum of 14 liters was needed for elutriate preparation and benthic bioassays. Sediments in the buckets representing each composite area were homogenized at Kinnetic Laboratories’ Santa Cruz facility before delivery to the bioassay laboratory. Bioassay samples were delivered to Pacific EcoRisk on December 8, 2015. Sediment chemistry samples were received by Eurofins Calscience on December 10. Except for archival material, sediment chemistry containers were completely filled to minimize air bubbles being trapped in the sample container. A small amount of headspace was allowed for sediment archive samples to prevent container breakage during freezing. For the preservation of all samples, filled containers were placed on ice immediately following sampling and maintained at 2 to 4°C until analyzed. Sediment archive samples were placed on ice initially and then frozen as soon as possible. The sample containers were sealed to prevent any moisture loss and possible contamination.

26

3.3.4 Equipment Decontamination All sample contact surfaces were stainless steel, polyethylene or Teflon® coated. Compositing tools were stainless steel or Teflon® coated stainless steel. Except for the core liners, all contact surfaces of the sampling devices and the coring tubes were cleaned for each sampling area. The cleaning protocol consists of a site water rinse, a Micro-90 soap wash, and then finished with deionized water rinses. The polyethylene core liners were new and of food grade quality. All rinseate was collected in containers and disposed of properly. 3.3.5 Reference Site (Dredge Material Placement Area) Sampling An airboat was used to access Prospect Island reference sites, as access was difficult by any other means such as driving or hiking. The top six inches of sediment were collected from each reference location using a four-inch diameter stainless steel hand auger. A total of three augers were required at each location in order to obtain enough material for all the testing. Any large debris or plant matter was removed from the samples prior to compositing. Positioning, logging, decontamination, compositing, sample handling and preservation procedures were the same as that for the vibracore samples. 3.3.6 Water Sampling Water was collected from the middle of the Miner Slough Spur Channel for use in preparing elutriates for chemical analyses and bioassays. A sample of background water was also collected to assess ambient aquatic chemistry. Water was pumped from mid-depth according to protocol, using a pre-cleaned hose. Water for background chemistry was placed directly into in jars supplied by the analytical laboratory. Water for elutriate preparation was placed in QC grade cubitainers (30 L). Water samples were iced and shipped over night to the analytical and bioassay laboratories on December 8 for the background water samples and December 10 for the elutriate samples. 3.3.7 Documentation and Sample Custody All samples had their containers physically marked with sample location. 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 along with sampling coordinates, weather conditions, wave height, sediment physical characteristics, and any deviations from this SAP and reasons for those deviations. A copy of the field data logs is included as Appendix A. Samples were considered to be “in custody” if they were (1) in the custodian’s possession or view, or (2) in a secured place (locked) with restricted access. Standard COC procedures were used for all samples collected, transferred, and analyzed as part of this project. COC forms were used to identify the samples, custodians, and dates of transfer. Except for the shipping company, each person who has custody of the samples signed the COC form and ensured samples are stored properly and not left unattended unless properly secured.

Standard information on COC forms includes:

27

Sample Identification Sample Collection Date and Time Sample Matrices (e.g., marine sediment) Analyses to be Performed Container Types Preservation Method Sampler Identification Dates of Transfer Names of Persons with Custody

The completed COC forms were placed in sealable plastic bags that were placed in the coolers with the samples. COC forms were immediately signed by a laboratory representative upon receipt. Copies of the completed COCs are included with the analytical and bioassay reports in Appendices C and D, respectively. 3.4 Laboratory Testing Methods Chemical and biological analyses were initiated as soon as practical after the collection of samples. Physical, chemical and biological testing for this Project were primarily carried out by Calscience Laboratories (Cal-ELAP No. 2944) and Pacific EcoRisk (NELAP No. 04225CA) using USEPA and USACE approved methodologies. 3.4.1 Bulk Sediment Chemical Analyses Bulk sediment chemistry analyses were conducted on all Miner Slough Spur Channel and dredge material placement area composite samples at Prospect Island. Analytical parameters, methods, and quantification limits are presented in Table 3. Sediment samples were analyzed in a manner consistent with guidelines for dredge material testing methods in the ITM. Samples were extracted and analyzed within specified EPA holding times, and were accomplished with appropriate quality control measures. 3.4.2 Elutriate Testing Sediments for the SET were prepared following methods described in the ITM (USEPA and USACE, 1998). A slurry of sediment and site water were prepared at a concentration of 1:4 on a volume basis at room temperature. The slurry was mixed for thirty minutes to a uniform consistency with a laboratory mixer, and then allowed to settle for a period of time. The supernatant was then carefully siphoned into appropriate sample containers. Elutriate samples along with the background water sample were analyzed for a variety of constituents including conventional analytes (total suspended solids, pH, hardness, total dissolved solids, chloride, BOD and COD), oil and grease, total ammonia, metals, hexavalent chromium, tributyltin, chlorinated pesticides, organophosphate compounds, PCBs and PAHs. Except for mercury and selenium, elutriate extracts were filtered through a 0.45 micron filter prior to metal analyses. Test methods and target reporting limits achieved for the background water and elutriate analyses are listed in Table 4.

28

Elutriate samples were also used as test media for bioassay tests. For these samples, the sediment and water slurries were allowed to settle for an hour after initial vigorous mixing. 3.4.3 DI-WET Testing The DI-WET involves extracting 50 grams of sediment for 24 hours at a ratio of one part sediment to ten parts deionized water. The extract was filtered through a 0.45-micron filter prior to analysis. Simulated leachate was analyzed from the Miner Slough Spur Channel composite samples using the list of analytes and protocols specified in Table 5. Analytical results were reported as micrograms of each constituent per liter of extractant. 3.4.4 Acute Toxicity Testing In order to determine whether suspended sediments at the dredge site meets toxicity water quality requirements, water column bioassays were performed on the Miner Slough Spur Channel sediment composite samples using the standard elutriates. Five concentrations of elutriate (100%, 50%, 10%, 5% and 1%) were prepared using water used to culture the animals for the dilution. Elutriates were made from test sediments and site water as described in Section 3.4.2. The background waters were analyzed for all constituents of concern. Each elutriate extract along with laboratory and site water controls were tested for acute toxicity following ITM (USEPA and USACE, 1998) recommended guidelines. Pimephales promelas (fathead minnow) was tested using procedures from EPA/821/R/02/012 (USEPA, 2002b). Ninety-six hour survival is the endpoint for this acute test. The toxicity test data from the dredge area samples were statistically compared to the toxicity data from tests carried out on the laboratory controls. Since ammonia is often a confounding factor, it was reported along with the toxicity data. Complete methods for the water column testing can be found in the bioassay report in Appendix D. Benthic species used for this Project are the freshwater amphipod Hyalella Azteca and the freshwater midge Chironomus dilutus. Testing procedures followed EPA 600/R-99/064 (March 2000a) and ITM guidelines. Ten-day survival is the endpoint for these acute tests. Complete methods for the benthic tests can be found in the bioassay report in Appendix D.

29

4.0 RESULTS Results of all physical, chemical and biological testing of the Miner Slough Spur Channel composite samples are provided in a series of summary tables that follow. These tables do not include QA/QC data. Complete results including all associated QA/QC data are provided in the lab reports in the appendices. See Appendix C for all physical and chemical analyses and Appendix D for all biological testing data. 4.1 Sediment Physical and Chemical Results A summary of the physical and chemical testing results for the five Miner Slough Spur Channel composite samples are provided in Table 6. Included in Table 6 are screening values consisting of NOAA SQuiRT sediment screening values and mean Delta sediment concentrations, plant screening values and terrestrial life screening values from the DDRS. Also included in Table 6 are sediment chemistry data from the two composite samples collected in the Prospect Island reference (placement) area. Any testing values that exceed any of these screening values are highlighted according to the footnotes at the bottom of Table 6. Data contained in Table 6 is often coded. Values that were not detected above the method detection limit were assigned a “<” prefix symbol. Values estimated between the MDL and reporting limit were tagged with a “J”. A “J” code may also indicate an estimated value due to that value being outside of certain QA/QC objectives. Definitions of all other symbols are described in the QA/QC report in Appendix E and in table footnotes. 4.2 SET Chemical and DI-WET Chemistry Results Results of the chemical analyses of the 100% SET extracts from the five composite samples are provided in Table 7. Results of the inorganic analyses of the DI-WET extracts from the five composite samples are provided in Table 8. Values for SET selenium and mercury represent the total fraction. Values for all other SET metals are reported as the dissolved fraction. All DI-WET metals are reported as the dissolved fraction. Included in Tables 7 and 8 are numeric water quality objectives specified in the Water Quality Control Plan (Basin Plan) for the Sacramento and San Joaquin Rivers (CVRWQCB, 2015), draft General Waste Discharge Requirements for Medium Scale Dredging Operations in the Sacramento-San Joaquin Delta (CVRWQCB, undated), and the California Toxics Rule (USEPA, 2000a). Also included in Table 7 are concentrations from a background water sample representing the water used to prepare the elutriate extracts. Values exceeding water quality objectives are highlighted according to footnotes for Tables 7 and 8. SET and DI-WET qualification codes are the same as those for the sediment data. 4.3 Solid Phase Bioassay Results Replicate and mean survival for the 10-day acute solid phase bioassays conducted on the five composite samples as well as the Prospect Island reference samples are provided in Table 9 for the amphipod Hyalella azteca and Table 10 for the larval midge Chironomus dilutes.

30

4.4 Suspended Particulate Phase (SPP) Bioassay Results Mean percent survival and supporting replicate data for the 96-hour static acute SPP bioassays using the Fathead Minnow, Pimephales promelas are provided in Table 11 along with calculated LC50 values. Table 11 includes results for each replicate exposure to 100%, 50%, 10%, 5%, and 1% elutriate concentrations along with a 0% control concentration.

31

Table 6. Miner Slough Spur Channel 2015 Sediment Chemistry Results.

Analyte Name UNITS

Miner Slough Spur Channel Composite Samples (MSSCVC15-) Prospect Island Ref.

(PI-REF15-) NOAA SQuiRT Values1 DDRS Screening Values2

A B C D E A B TEL PEL TEC PEC Delta Sediment Concentrations Mean (Range)

Plant Screening

Values

Terrestrial Screening

Values Particle Size Clay (less than 0.00391mm) % 24.9 25.8 34.9 27.7 35.9 34.0 29.7 Silt (0.00391 to 0.0625mm) % 75.1 74.2 65.1 72.3 64.1 66.0 70.3 Total Silt and Clay (0 to 0.0625mm) % 100 100 100 100 100 100 100 Fine Sand (0.125 to 0.25mm) % <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 Medium Sand (0.25 to 0.5mm) % <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 Coarse Sand (0.5 to 1mm) % <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 Very Coarse Sand (1 to 2mm) % <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 Gravel (greater than 2mm) % <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 Very Fine Sand (0.0625 to 0.125mm) % <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 Conventionals

Ammonia (as N) mg/kg 28 26 21 16 10 11 9.6

Total Solids % 69.1 66.4 68.9 71.3 74.1 54.2 53.9 pH pH units 6.65 7.45 7.47 7.71 6.75 6.90 6.95 Cation Exchange Capacity (Sodium) MEQ/0.1kg 22.4 24.7 25.6 14.8 17.6 51.6 49 Acid Generation Potential t CaCO3/Kt 0.63J 0.31J <0.31 <0.31 <0.31 1.25J 1.25J Acid Neutralization Potential t CaCO3/Kt 17 19 23 25 13 23 25 NP:AGP Ratio 27.0 61.3 74.2 80.6 41.9 18.4 20.0 Dissolved Sulfides mg/kg <0.017 <0.017 <0.017 <0.017 <0.017 <0.017 <0.017

Total Sulfides mg/kg <0.12 0.15 0.15 1.3 0.2 <0.15 <0.16

Total Organic Carbon % 0.8 0.87 0.67 0.56 0.5 3.3 2

O&G mg/kg 29 <12 <11 <11 14 <15 <15 176 (0.13-1197)

TRPH mg/kg <12 <12 <12 <11 <11 <15 <15 Metals Aluminum mg/kg 20,000 23,400 23,500 22,500 19,700 28,800 30,200 16,086 (8500-23667) 50 60 Antimony mg/kg 0.132J- 0.155J- 0.111J- 0.075J- 0.0814J- 0.181J- 0.15J- 0.43 (0.001-1.8) 5 0.142

Arsenic mg/kg 6.81 7.71 5.26 3.68 3.73 5.27 5.08 5.9 17 9.79 33 6.77 (0.263-72) 10 60

Barium mg/kg 170 161 194 188 161 216 235 148 (0.001-570) 500 1.04 Beryllium mg/kg 0.436J 0.581J 0.56J 0.619J 0.461J 0.825J 0.757J 0.269 (0.1-0.62) 10 1.06 Boron mg/kg <14.2 <14.8 <14.3 <13.8 <13.3 <18.2 <18.3 0.5

Cadmium mg/kg 0.698 0.716 0.43 0.338 0.274 0.585 0.513 0.596 3.53 0.99 4.98 1.31 (0.05-10.2) 4 20

Chromium, Hexavalent mg/kg <0.0078 <0.0081 <0.0078 <0.0076 <0.0073 <0.0099 <0.01 Chromium mg/kg 64.5 73.4 78.2 71.7 63.6 91 102 37.3 90 43.4 111 42.6 (0.5-120) 1 Cobalt mg/kg 18.6 19.1 20.5 19.3 19.8 22.6 24.8 10.5 (1.72-18) 20 0.14 Copper mg/kg 56.1 60.1 48.1 41.7 32.1 64.9 67 35.7 197 31.6 149 40 (0.5-438) 100 50

Lead mg/kg 12.7 13.6 11 9.27 7.06 13.3 13.3 35 91.3 35.8 128 11.2 (0.5-71.4) 50 500

Manganese mg/kg 551 587 599 631 508 484 593 630 500

Mercury mg/kg 0.177 0.313 0.14 0.0937 0.0574 0.128 0.123 0.174 0.486 0.18 1.06 0.701 (0.01-37) 0.3 0.1

Molybdenum mg/kg 0.465 0.574 0.347 0.269J 0.309 0.489 0.391 (0.115-12) 2

Nickel mg/kg 92 86.8 124 123 105 145 162 18 36 22.7 48.6 48.5 (0.161-190) 30 200

Selenium mg/kg 0.186 0.298 0.229 0.136J 0.142 0.19 0.328 2.98 (0.04-21) 70

32

Table 6 Continued. Miner Slough Spur Channel 2015 Sediment Chemistry Results.

Analyte Name UNITS




Plant Screening

Values


Values Silver mg/kg 0.154 0.22 0.106J 0.0678J 0.0475J 0.116J 0.117J 1.04 (0.05-4.83) 2 4.04

Thallium mg/kg 0.0575J 0.0876J 0.0639J 0.0542J 0.07J 0.0877J 0.0789J 1.41 (0.05-49) 1 0.057

Vanadium mg/kg 63 79.4 62.7 62.4 57.4 87.4 88.3 50.8 (0.1-120) 2 1.59 Zinc mg/kg 109 105 86.5 77.9 65 113 122 123 315 121 459 75.4 (0.1-250) 50 200 Methylmercury µg/kg 0.144 0.060J 0.067 0.075 0.035J 0.442 0.28 OC Pesticides 2,4'-DDD µg/kg <0.11 <0.12 <0.11 <0.11 <0.1 0.31J 0.46 2,4'-DDE µg/kg <0.051 <0.053 <0.051 <0.049 <0.047 0.3J 0.48 2,4'-DDT µg/kg <0.09 <0.094 <0.091 <0.087 <0.084 <0.11 <0.11

4,4'-DDD µg/kg 0.38 1.2 0.097J <0.056 0.3 0.14J 0.4 3.54 8.51 4.88 28 3.89 (3.0-6.0) 758

4,4'-DDE µg/kg 2.8 3.9 1.8 <0.057 3 4.9 7 1.42 6.75 3.16 31.3 7.04 (2.8-21) 596 4,4'-DDT µg/kg <0.076J- <0.08J- <0.077J- <0.074J- <0.071J- <0.097J- <0.097J- 1.19 4.77 4.16 62.9 9 (3.0-15) 18 Total DDTs µg/kg 3.18 5.1 1.897 ND 3.3 5.65 8.34 7 4450 5.28 572 4,4'-Dichlorobenzophenone µg/kg <0.35 <0.36 <0.35 <0.34 <0.32 <0.44 <0.44 Aldrin µg/kg <0.055 <0.057 <0.055 <0.053 <0.051 <0.07 <0.07 3 Alpha-BHC µg/kg <0.083 <0.087 <0.084 <0.081 <0.078 <0.11 <0.11 100 Beta-BHC µg/kg <0.098 <0.1 <0.098 <0.095 <0.091 <0.12 <0.12 4 Delta-BHC µg/kg <0.13 <0.14 <0.14 <0.13 <0.13 <0.17 <0.17 Gamma-BHC µg/kg <0.05 <0.052 <0.05 <0.048 <0.047 <0.064 <0.064 0.94 1.38 2.37 4.99 5 Alpha Chlordane µg/kg <0.097 <0.1 <0.097 <0.094 <0.09 <0.12 0.3J Gamma Chlordane µg/kg <0.077 <0.081 <0.078 <0.075 <0.072 <0.099 0.22J Oxychlordane µg/kg <0.11 <0.11 <0.11 <0.1 <0.098 <0.13 <0.13 Total Chlordane µg/kg ND ND ND ND ND ND 0.73 4.5 8.9 3.24 17.6 224 Cis-nonachlor µg/kg <0.074 <0.077 <0.074 <0.071 <0.069 <0.094 <0.094 Dieldrin µg/kg <0.15 <0.16 <0.15 <0.15 <0.14 <0.2 <0.2 2.85 6.67 1.9 61.8 2 Endosulfan Sulfate µg/kg <0.15 <0.16 <0.15 <0.15 <0.14 <0.19 <0.19 119 Endosulfan I µg/kg <0.084 <0.088 <0.084 <0.081 <0.078 <0.11 <0.11 119 Endosulfan II µg/kg <0.13 <0.14 <0.13 <0.13 <0.12 <0.17 <0.17 119 Endrin µg/kg <0.082J- <0.086J- <0.083J- <0.079J- <0.076J- <0.1J- <0.1J- 2.67 62.4 2.22 10 Endrin Aldehyde µg/kg <0.14 <0.15 <0.15 <0.14 <0.13 <0.18 <0.18 11 Endrin Ketone µg/kg <0.08J- <0.084J- <0.081J- <0.078J- <0.075J- <0.1J- <0.1J- Heptachlor µg/kg <0.074 <0.078 <0.075 <0.072 <0.069 <0.095 <0.095 6 Heptachlor Epoxide µg/kg <0.064 <0.067 <0.065 <0.062 <0.06 <0.082 <0.082 0.6 2.74 2.47 16 152 Methoxychlor µg/kg <0.098 <0.1 <0.098 <0.095 <0.091 <0.12 <0.12 20 Mirex µg/kg <0.057 <0.059 <0.057 <0.055 <0.053 <0.072 <0.072 Toxaphene µg/kg <13 <14 <13 <12 <12 <17 <17 0.1 119 Trans-nonachlor µg/kg <0.062 <0.065 <0.063 <0.06 <0.058 <0.079 0.21J Butyltins Dibutyltin µg/kg <1.1 <1.1 <1.1 <1 <0.99 <1.3 <1.4 43.9 (0.64-270) Monobutyltin µg/kg <2 <2 <2 <1.9 <1.9 <2.5 <2.6 6.71 (0.82-15.1) Tetrabutyltin µg/kg <1.1 <1.1 <1.1 <1 <1 <1.4 <1.4 17.24

33


Analyte Name UNITS




Plant Screening

Values


Values Tributyltin µg/kg <2.2 <2.2 <2.2 <2.1 <2 <2.7 <2.8 75.7 (1.0-586) PCB Aroclors Aroclor-1016 µg/kg <15 <16 <15 <14 <14 <19 <19 Aroclor-1221 µg/kg <31 <32 <31 <29 <29 <39 <39 Aroclor-1232 µg/kg <18 <19 <18 <17 <17 <23 <23 60 Aroclor-1242 µg/kg <19 <19 <18 <18 <17 <24 <24 Aroclor-1248 µg/kg <23 <24 <23 <22 <22 <30 <29 277 Aroclor-1254 µg/kg <23 <24 <23 <22 <21 <29 <29 60 340 Aroclor-1260 µg/kg <23 <24 <23 <22 <21 <29 <29 Aroclor-1262 µg/kg <24 <25 <24 <23 <22 <30 <30 Total Aroclors µg/kg ND ND ND ND ND ND ND 34.1 277 59.8 676 40,000 0.332 OP Pesticides Azinphos Methyl µg/kg <6.5 <6.8 <6.5 <6.4 <6.1 <8.4 <8.5 Bolstar µg/kg <9.9 <10 <9.9 <9.6 <9.2 <13 <13 Chlorpyrifos µg/kg <9.6 <10 <9.6 <9.4 <9 <12 <12 Coumaphos µg/kg <14 <14 <14 <13 <13 <18 <18 Demeton-o/s µg/kg <13 <14 <13 <13 <12 <17 <17 Diazinon µg/kg <12 <13 <12 <12 <11 <16 <16 Dichlorvos µg/kg <8 <8.4 <8 <7.8 <7.5 <10 <10 Disulfoton µg/kg <11 <12 <11 <11 <11 <15 <15 Ethoprop (Ethoprofos) µg/kg <11 <12 <11 <11 <11 <15 <15 Fenchlorphos (Ronnel) µg/kg <7.9 <8.3 <7.9 <7.7 <7.4 <10 <10 Fensulfothion µg/kg <8.4 <8.8 <8.5 <8.2 <7.9 <11 <11 Fenthion µg/kg <8.3 <8.6 <8.3 <8 <7.7 <11 <11 Merphos µg/kg <11 <12 <11 <11 <11 <15 <15 Methyl Parathion µg/kg <9.8 <10 <9.8 <9.6 <9.2 <13 <13 0.34 Mevinphos µg/kg <9.1 <9.5 <9.1 <8.9 <8.5 <12 <12 Naled µg/kg <54 <57 <55 <53 <51 <70 <70 Phorate µg/kg <9.1 <9.6 <9.2 <8.9 <8.6 <12 <12 0.496 Tetrachlorvinphos (Stirophos) µg/kg <44 <46 <44 <43 <41 <56 <57 Tokuthion (Prothiofos) µg/kg <7.9 <8.2 <7.9 <7.7 <7.4 <10 <10 Trichloronate µg/kg <7.9 <8.3 <7.9 <7.7 <7.4 <10 <10 PAHs 1-Methylnaphthalene µg/kg <12 <6.1 <5.9 <11 <11 <7.5 <7.5 1-Methylphenanthrene µg/kg <3.6 <1.9 <1.8 <3.4 <3.3 <2.3 <2.3 2,3,5-Trimethylnaphthalene µg/kg <4.7 <2.5 <2.4 <4.6 <4.4 <3 <3.1 2,6-Dimethylnaphthalene µg/kg <5 <2.6 <2.5 <4.8 <4.6 4.3J <3.2 2-Methylnaphthalene µg/kg <13 <6.9 <6.7 <13 <12 <8.4 <8.5 Acenaphthene µg/kg <13 <7 <6.8 <13 <13 <8.6 <8.7 6.71 88.9 20,000 682,000 Acenaphthylene µg/kg <13 <6.9 <6.6 <13 <12 <8.4 <8.5 5.87 128 682,000 Anthracene µg/kg <14 <7.5 <7.3 <14 <13 <9.2 <9.3 46.9 245 57.2 845 13.3 (3.9-26) 1,480,000

Benzo (a) Anthracene µg/kg 22J 9.2J 7.2J <12 <12 <8.2 8.3J 31.7 385 108 1,050 43.4 (6.8-140) 5210

34


Analyte Name UNITS




Plant Screening

Values


Values Benzo (a) Pyrene µg/kg 44 22 16 <13 <13 14J 13J 31.9 782 150 1,450 52.7 (9.8-140) 1520

Benzo (b) Fluoranthene µg/kg 36 14J 14J <14 <13 14J 13J 49.7 (4.4-160) 59,800

Benzo (e) Pyrene µg/kg 37 22 15 5.8J <5.3 15J 15J 7.05 (1.0-11)

Benzo (g,h,i) Perylene µg/kg 62 26 23 <14 <13 21 22 31 (12-150) 119,000

Benzo (k) Fluoranthene µg/kg 18J 12J <7 <13 <13 <8.9 9.1J 27.2 2.37 4.99 30.7 (4.2)-120) 148,000

Biphenyl µg/kg <5.3 <2.7 <2.7 <5.1 <4.9 <3.4 <3.4

Chrysene µg/kg 31 15 10J <12 <11 13J 14J 57.1 862 166 1,290 79.7 (19-150) 4730

Dibenz (a,h) Anthracene µg/kg <13 <7 <6.8 <13 <13 <8.6 <8.6 6.22 135 33 17.6 18,400 Dibenzothiophene µg/kg <4.4 <2.3 25 <4.3 <4.1 <2.8 <2.8

Fluoranthene µg/kg 62 30 18 <14 <13 26 19 111 2355 423 2,230 93.5 (6.7-259) 122,000

Fluorene µg/kg <14 <7.5 <7.3 <14 <13 <9.2 <9.3 21.2 144 77.4 536 122,000 30,000

Indeno (1,2,3-c,d) Pyrene µg/kg 46 19J 18J <18 <17 14J 17J 17.32 20.4 (4.1-58) 109,000

Naphthalene µg/kg <12 <6.3 <6.1 <12 <11 <7.7 <7.7 34.6 391 470 561 99

Perylene µg/kg 110 120 49 41 22J 19 26

Phenanthrene µg/kg 24J 13J <7.3 <14 <13 9.4J 9.6J 41.9 515 1,800 1,170 25.3 (2.9-100) 45,700

Pyrene µg/kg 95 42 28 <12 <11 31 25 53 875 195 1,520 37.9 (6.0-160) 78,500

Low MW PAH µg/kg 24 13 25 ND ND 13.7 9.6 76.4

High MW PAH µg/kg 563 331.2 198.2 46.8 22 167 181.4 193

Total PAHS µg/kg 587 344.2 223.2 46.8 22 180.7 191 264 1,610 22,800 1 Buchman, M.F. 2008. Screening Quick Reference Tables, NOAA OR&R Report 08-1. Seattle, Washington. Office of Response and Restoration, National Oceanic and Space Administration, 34 pages. TELs italicized are H. azteca TEL values (EPA 905-R96-008). California Regional Water Quality Control Board, Central Valley Region; California Department of Fish and Game; Delta Protection Commission; 2002. Delta Dredging and Reuse Strategy. Volumes I and II, June 2002.

Bold values exceed one or both NOAA SQuiRT lower effects screening values (Buchman, 2008). Bod and Underlined exceed one or both NOAA SQuiRT upper effects screening values (Buchman, 2008). Values in Red exceed mean Delta Sediment Concentrations (CVRWQCB, 2002). Values shaded in green exceed plant screening values (CVRWQCB, 2002). Values shaded in blue exceed terrestrial life screening values (CVRWQCB, 2002). Values shaded in orange exceed both plant and terrestrial life screening values (CVRWQCB, 2002). Values boxed in blue exceed one or both Prospect Island reference concentrations. ND = Not Detected “U” qualifier indicates analyte was not found at or above the associated reporting limit. “UJ” qualifier indicates that the analyte was analyzed for but was not detected. The reported quantitation limit is approximate and may be inaccurate or imprecise. “J” qualifier indicates that the result is an estimated quantity. Often indicates results between the MDL and RL. “J-“ qualifier indicates that the result is an estimated quantity but result may be biased low. “R” qualifier indicates that the data are unusable (the analyte may or may not be present).

35

Table 7. Standard Elutriate and Background Water Results for Miners Slough 2015.

Analyte UNITS

Miner Slough Spur Channel Composite Samples (MSSCVC15-SET-) Bckgrnd

Water

CA Toxics Rule1 Basin Plan Max2

DDRS Surface Water

Objective3 A B C D E CCC CMC

Conventionals

Ammonia (as N) mg/L 1.8 2.0 1.8 1.2 2.0 0.42 11.4 Chloride mg/L 11 10 11 10 11 10 Total Suspended Solids mg/L 720 1000 901 806 2360 2.6 Total Dissolved Solids mg/L 215 280 285 335 600 98 125 450

pH pH units 6.47 6.7 7.59 6.81 6.72 7.17 6.5-8.5 Chemical Oxygen Demand mg/L 51 67 53 51 99 15 Biochemical Oxygen Demand mg/L 29 27 23 27 60 1.3 Hardness (as CaCO3) mg/L 89 100 120 120 150 66 Oil and Grease mg/L <0.80 <0.80 <0.80 <0.80 1.1 <0.80

Total Metals

Mercury µg/L 0.179 0.24 0.15 0.0631 0.188 0.000967 200 Selenium µg/L 0.289J 0.443J 0.282J 0.209J 0.615J <0.168 1,000

Dissolved Metals

Aluminum µg/L 151 216 164 119 301 61.4 87

Antimony µg/L 0.655J 0.676J 0.687J 0.461J 0.476J 0.126J 6

Arsenic µg/L 3.98 3.85 1.59 1.39 1.8 1.16 150 340 10 10

Barium µg/L 229 226 251 284 331 21.5 100 100

Beryllium µg/L <0.290 <0.290 <0.290 <0.290 <0.290 <0.290 4

Boron µg/L 94.1 105 97.4 96.4 107 67.4 630

Cadmium µg/L <0.128 <0.128 <0.128 <0.128 <0.128 <0.128 2.2 4 4.3 4 2.23

Chromium, Hexavalent µg/L <4.0 <4.0 <4.0 <4.0 <4.0 <4.0 11 16 11

Chromium µg/L 0.704J 0.9J 0.657J 0.7J 0.813J 0.859J 180 4 550 4 50

Cobalt µg/L 0.376J 0.285J 0.337J 0.393J 0.302J <0.0919

Copper µg/L 1.05 1.55 1.39 2.91 2.56 1.42 9.0 4 13 4 10 9

Lead µg/L 0.384J 0.327J 0.342J 0.346J 0.451J <0.0898 2.5 4 65 4 2

Manganese µg/L 316 184 192 128 302 8.41 50 50

Molybdenum µg/L 1.47 1.55 1.5 1.31 2.56 0.635J 10

Nickel µg/L 1.48 1.61 1.69 2.73 1.42 1.1 52 4 470 4 52

Silver µg/L <0.111 <0.111 <0.111 <0.111 <0.111 <0.111 3.4 4 10 3.4

36

Table 7 Continued. Standard Elutriate and Background Water Results for Miners Slough 2015.

Analyte UNITS

Miner Slough Spur Channel Composite Samples (MSSCVC15-SET-) BG

Water


DDRS Surface Water

Objective 3A B C D E CCC CMC

Thallium µg/L <0.101 <0.101 <0.101 <0.101 <0.101 <0.101 1.7

Vanadium µg/L 0.753J 1.65 1.56 1.71 0.284J 2.91 100

Zinc µg/L 144 94.2 94.8 91.4 91.7 4.72J 120 4 120 4 100 100

Methylmercury ng/L 0.395 0.109J+ 0.332 1.2 <0.015J- 0.061

OC Pesticides

2,4'-DDD µg/L <0.00045 <0.00045 <0.00045 <0.00046 <0.00045 <0.00046 2,4'-DDE µg/L <0.00047 <0.00047 <0.00047 <0.00048 <0.00047 <0.00048 2,4'-DDT µg/L <0.00058 <0.00058 <0.00058 <0.00059 <0.00058 <0.00060 4,4'-DDD µg/L <0.00049 <0.00049 <0.00049 <0.00050 <0.00049 <0.00050 0.00083 4,4'-DDE µg/L <0.00073 <0.00073 <0.00073 <0.00074 <0.00073 <0.00075 0.00059 4,4'-DDT µg/L <0.00084 <0.00084 <0.00084 <0.00085 <0.00084 <0.00086 0.001 1.1 0.00059

Total DDT's µg/L ND ND ND ND ND ND 4,4'-Dichlorobenzophenone µg/L <0.0018 <0.0018 <0.0018 <0.0018 <0.0018 <0.0018 Aldrin µg/L <0.00065 <0.00065 <0.00065 <0.00066 <0.00065 <0.00067 3 0.00013 Alpha-BHC µg/L <0.00033 <0.00033 <0.00033 <0.00034 <0.00033 <0.00034 0.0039 Beta-BHC µg/L <0.00037 <0.00037 <0.00037 <0.00037 <0.00037 <0.00037 0.014 Delta-BHC µg/L <0.00059 <0.00059 <0.00059 <0.00061 <0.00059 <0.00061

Gamma-BHC µg/L <0.00073 <0.00073 <0.00073 <0.00075 <0.00073 <0.00075 0.95 0.019 Alpha Chlordane µg/L <0.00045 <0.00045 <0.00045 <0.00046 <0.00045 <0.00047 0.00057 Gamma Chlordane µg/L <0.00065 <0.00065 <0.00065 <0.00066 <0.00065 <0.00066 Oxychlordane µg/L <0.00053 <0.00053 <0.00053 <0.00054 <0.00053 <0.00054 Total Chlordane µg/L ND ND ND ND ND ND 0.0043 2.4 Cis-nonachlor µg/L <0.00054 <0.00054 <0.00054 <0.00055 <0.00054 <0.00056

Dieldrin µg/L <0.00056 <0.00056 <0.00056 <0.00057 <0.00056 <0.00057 0.056 0.24 0.00014 Endosulfan Sulfate µg/L <0.00080 <0.00080 <0.00080 <0.00082 <0.00080 <0.00082 110 Endosulfan I µg/L <0.00072 <0.00072 <0.00072 <0.00073 <0.00072 <0.00074 0.056 0.22 0.056 Endosulfan II µg/L <0.00080 <0.00080 <0.00080 <0.00082 <0.00080 <0.00082 0.056 0.22 110 Endrin µg/L <0.00086 <0.00086 <0.00086 <0.00088 <0.00086 <0.00089 0.036 0.086 0.036 Endrin Aldehyde µg/L <0.00074 <0.00074 <0.00074 <0.00076 <0.00074 <0.00076 0.76

Endrin Ketone µg/L <0.00084 <0.00084 <0.00084 <0.00086 <0.00084 <0.00087

37


Analyte UNITS


Water


DDRS Surface Water


Heptachlor µg/L <0.00073 <0.00073 <0.00073 <0.00074 <0.00073 <0.00075 0.0038 0.52 0.00021 Heptachlor Epoxide µg/L <0.00052 <0.00052 <0.00052 <0.00053 <0.00052 <0.00053 0.0038 0.52 0.0001 Methoxychlor µg/L <0.00064 <0.00064 <0.00064 <0.00065 <0.00064 <0.00066 0.03 Mirex µg/L <0.00046 <0.00046 <0.00046 <0.00046 <0.00046 <0.00047 Toxaphene µg/L <0.044 <0.044 <0.044 <0.044 <0.046 <0.045 0.0002 0.73 0.00073

Trans-nonachlor µg/L <0.00058 <0.00058 <0.00058 <0.00059 <0.00058 <0.00060

Butyltins Monobutyltin µg/L <0.0023 <0.0023 <0.0023 <0.0023 <0.0024 <0.0023 Dibutyltin µg/L <0.0018 <0.0018 <0.0017 <0.0017 <0.0018 <0.0017 Tributyltin µg/L <0.0013 <0.0013 <0.0013 <0.0013 <0.0014 <0.0013 0.0726

Tetrabutyltin µg /L <0.0019 <0.0019 <0.0019 <0.0019 <0.0019 <0.0019

Arococlors Aroclor-1016 µg/L <0.14 <0.14 <0.14 <0.14 <0.15 <0.14 Aroclor-1221 µg/L <0.13 <0.13 <0.13 <0.13 <0.14 <0.14 Aroclor-1232 µg/L <0.12 <0.12 <0.12 <0.12 <0.12 <0.12 Aroclor-1242 µg/L <0.060 <0.060 <0.060 <0.060 <0.062 <0.061 Aroclor-1248 µg/L <0.096 <0.096 <0.096 <0.096 <0.10 <0.098

Aroclor-1254 µg/L <0.11 <0.11 <0.11 <0.11 <0.11 <0.11 Aroclor-1260 µg/L <0.13 <0.13 <0.13 <0.13 <0.13 <0.13 Total Aroclors µg/L ND ND ND ND ND ND 0.00017

PAHs 1-Methylnaphthalene µg/L <0.027 <0.028 3.7 <0.027 <0.028 <0.028 1-Methylphenanthrene µg/L <0.025 <0.026 <0.025 <0.025 <0.026 <0.025

2,3,5-Trimethylnaphthalene µg/L <0.10 <0.11 0.17J <0.11 <0.11 <0.11 2,6-Dimethylnaphthalene µg/L <0.021 <0.022 1.7 <0.021 <0.022 <0.021 2-Methylnaphthalene µg/L <0.025 <0.026 6.7 <0.025 <0.026 <0.026 Acenaphthene µg/L <0.020 <0.021 <0.020 <0.020 <0.021 <0.020 1,200 Acenaphthylene µg/L <0.017 <0.018 <0.017 <0.017 <0.018 <0.017 Anthracene µg/L <0.032 <0.034 <0.033 <0.033 <0.034 <0.033 9,600

Benzo (a) Anthracene µg/L <0.023 <0.024 <0.023 <0.023 <0.024 <0.023 0.0044

38


Analyte UNITS


Water


DDRS Surface Water


Benzo (a) Pyrene µg/L <0.035 <0.036 <0.035 <0.035 <0.036 <0.035 0.0044 Benzo (b) Fluoranthene µg/L <0.024 <0.025 <0.024 <0.024 <0.025 <0.024 0.0044 Benzo (e) Pyrene µg/L <0.0095 <0.010 <0.0096 <0.0096 <0.010 <0.0098 Benzo (g,h,i) Perylene µg/L <0.021 <0.022 <0.021 <0.021 <0.022 <0.021 Benzo (k) Fluoranthene µg/L <0.022 <0.023 <0.022 <0.022 <0.023 <0.023 0.0044

Biphenyl µg/L <0.013 <0.014 <0.013 <0.013 <0.014 <0.014 Chrysene µg/L <0.018 <0.019 <0.018 <0.018 <0.019 <0.018 Dibenz (a,h) Anthracene µg/L <0.026 <0.027 <0.026 <0.026 <0.027 <0.026 Dibenzothiophene µg/L <0.051 <0.054 <0.052 <0.052 <0.054 <0.053 Fluoranthene µg/L <0.026 <0.027 <0.026 <0.026 <0.027 <0.027 300 Fluorene µg/L <0.023 <0.024 <0.023 <0.023 <0.024 <0.024 1,300

Indeno (1,2,3-c,d) Pyrene µg/L <0.021 <0.022 <0.021 <0.021 <0.022 <0.021 0.0044 Naphthalene µg/L <0.022 <0.023 0.22 <0.022 <0.023 <0.022 14 Perylene µg/L <0.016 <0.017 <0.016 <0.016 <0.017 <0.017 Phenanthrene µg/L <0.029 <0.031 0.042J <0.029 <0.031 <0.030 Pyrene µg/L <0.024 <0.025 <0.024 <0.024 <0.025 <0.024 960 Low Weight PAHs µg/L ND ND 12.53 ND ND ND

High Weight PAHs µg/L ND ND ND ND ND ND Total PAHs µg/L ND ND 12.53 ND ND ND

OP Pesticides Azinphos Methyl µg/L <0.091 <0.091 <0.092 <0.092 <0.091 <0.093 Bolstar (Sulprofos) µg/L <0.12 <0.12 <0.12 <0.12 <0.12 <0.13 Chlorpyrifos µg/L <0.058 <0.058 <0.058 <0.058 <0.058 <0.059 0.0155 0.014

Coumaphos µg/L <0.15 <0.15 <0.15 <0.15 <0.15 <0.15 Demeton-o/s µg/L <0.078 <0.078 <0.079 <0.079 <0.078 <0.081 Diazinon µg/L <0.060 <0.060 <0.061 <0.061 <0.060 <0.062 0.105 0.05 Dichlorvos µg/L <0.17 <0.17 <0.18 <0.18 <0.17 <0.18 Disulfoton µg/L <0.072 <0.072 <0.073 <0.073 <0.072 <0.074 Ethoprop (Ethoprofos) µg/L <0.088 <0.088 <0.089 <0.089 <0.088 <0.090

Fenchlorphos (Ronnel) µg/L <0.092 <0.092 <0.092 <0.092 <0.092 <0.094

39


Analyte UNITS


Water


DDRS Surface Water


Fensulfothion µg/L <0.098 <0.098 <0.099 <0.099 <0.098 <0.10 Fenthion µg/L <0.085 <0.085 <0.085 <0.085 <0.085 <0.087 Malathion µg/L <0.11 <0.11 <0.11 <0.11 <0.11 <0.11 0.1 Merphos µg/L <0.098 <0.098 <0.099 <0.099 <0.098 <0.10 Methyl Parathion µg/L <0.083 <0.083 <0.084 <0.084 <0.083 <0.085 0.013

Mevinphos µg/L <0.081 <0.081 <0.082 <0.082 <0.081 <0.083 Naled µg/L <0.64 <0.64 <0.65 <0.65 <0.64 <0.66 Phorate µg/L <0.096 <0.096 <0.097 <0.097 <0.096 <0.098 0.7 Tetrachlorvinphos (Stirophos)

µg/L <0.44 <0.44 <0.45 <0.45 <0.44 <0.45

Tokuthion (Prothiofos) µg/L <0.093 <0.093 <0.094 <0.094 <0.093 <0.096

Trichloronate µg/L <0.098 <0.098 <0.099 <0.099 <0.098 <0.10 1 CMC – Criteria Maximum Concentration is the highest level for a 1-hour average exposure not to be exceeded more than once every three years, and is synonymous with “acute”.

CCC – Criteria Continuous Concentration is the highest level for a 4-day average exposure not to be exceeded more than once every three years, and is synonymous with “chronic”. 40 CFR Part 131 (EPA, 2000).

2 Maximum concentrations specified in the Basin Plan for the Sacramento River and San Juaquin River Basins (CVRWQCB, 2015) 3 California Regional Water Quality Control Board, Central Valley Region; California Department of Fish and Game; Delta Protection Commission; 2002. Delta Dredging and Reuse Strategy. Volumes I

and II, June 2002. 4 Values based on average hardness value of 100 mg/L. 5 Chronic 4-day average. 6 Ambient freshwater aquatic life chronic criterion for tributyltin (TBT). USEPA (2003). Bolded values exceed the CTR chronic objectives. Bold and Underlined values exceed CTR acute objectives. Shaded values exceed the Basin Plan maximum concentrations for the Delta or DDRS surface waterobjectives.

ND = Not Detected “U” qualifier indicates analyte was not found at or above the associated reporting limit. “UJ” qualifier indicates that the analyte was analyzed for but was not detected. The reported quantitation limit is approximate and may be inaccurate or imprecise. “J” qualifier indicates that the result is an estimated quantity. Often indicates results between the MDL and RL. “J-“ qualifier indicates that the result is an estimated quantity but result may be biased low. “R” qualifier indicates that the data are unusable (the analyte may or may not be present).

40

Table 8. DI-WET Results for Miners Slough 2015.

Analyte UNITS

Miner Slough Spur Channel Composite Samples (MSSCVC15-)

WDR's1,2

Maximum Concentration

CA Toxics Rule4 Ca

MCLs5

A B C D E CCC CMC

Conventionals Hardness, Total (as CaCO3) mg/L 26 42 64 65 33 pH pH units 6.62 6.91 7.28 7.44 6.76 Dissolved Organic Carbon mg/L 2.8 3.2 2.6 2.7 3.8 Total Dissolved Solids mg/L 860 1830 425 435 2710 Specific Conductance umhos/cm 82000 110000 140000 140000 35000 Metals Aluminum ug/L 366 395 146 101 805 87 1,000 Antimony ug/L 1.48J 1.3J 1.08J 1.31J 0.562J 6 Arsenic ug/L 5.18 1.74 1.7 0.782J 2.29 10 150 340 10 Barium ug/L 63.8 59.2 89.1 103 120 100 2,000 Beryllium ug/L <0.29 <0.29 <0.29 <0.29 <0.29 4 Boron ug/L 29.7J 36.1J 18.1J 12.5J 22.7J 700 Cadmium ug/L 0.207J <0.128 <0.128 <0.128 <0.128 1.2 3 1.8 3 5 Chromium, Hexavalent mg/L <0.004 <0.004 <0.004 <0.004 <0.004 11 11 16 10 Chromium ug/L 0.715J 0.533J <0.402 <0.402 0.938J 93 3 290 3 100 Cobalt ug/L 0.708J 0.352J 0.222J 0.0978J 1.2 Copper ug/L 11.4 4.07 1.7 1.8 11.2 10 4.5 3 6.3 3 1,300 Lead ug/L 5.21 1.12 0.286J <0.0898 5.17 2.5 1 3 27 3 15 Manganese ug/L 416 257 148 0.841J 414 50 50 Mercury ug/L 0.011 0.00346 0.00384 0.0144 0.0278 0.05 2 Molybdenum ug/L 3.27 4 3.4 2.7 2.37 Nickel ug/L 1.91 1.57 1.24 1.58 2.88 52 26 3 240 3 100 Selenium ug/L 0.224J 0.187J 0.186J 0.595J <0.168 50 Silver ug/L <0.111J- <0.111J- <0.111J- <0.111J- <0.111J- 0.87 3 Thallium ug/L <0.101 <0.101 <0.101 <0.101 <0.101 100 Vanadium ug/L 4.92 5.84 3.69 4.86 7.36 Zinc ug/L 38.5 22.9 2.08 1.12J 18.4 100 60 3 60 3 5,000

41

Footnotes for Table 8: 1 Concentrations shall be determined using methods specified in the Monitoring and Reporting Program. Metal concentrations are dissolved except for lead, mercury, nickel, and boron, which are total recoverable. 2 To be determined using California Code of Regulations, Title 22 Waste Extraction Test modified to use de-ionized water. 3 Values based on average hardness value of 45 mg/L. 4 CMC – Criteria Maximum Concentration is the highest level for a 1-hour average exposure not to be exceeded more than once every three years, and is synonymous with “acute”.

CCC – Criteria Continuous Concentration is the highest level for a 4-day average exposure not to be exceeded more than once every three years, and is synonymous with “chronic”. 40 CFR Part 131 (EPA, 2000).

5 Maximum Contaminant Levels (MCLs), California Code of Regulations (CCR), Division 4, Chapter 15, Domestic Water Quality and Monitoring. Bolded values exceed the WDR criteria Underlined values exceed the CTR Chronic Criteria Shaded values exceed State for California MCL goals.

42

Table 9. Hyalella azteca Survival in the Miners Slough Spur Channel Sediments.

Sediment Site % Survival in Test Replicates Mean

% Survival Rep A Rep B Rep C Rep D Rep E Rep F Rep G Rep H

Lab Control 100 100 100 100 100 90 90 100 97.5

MSSCVC15-A 100 90 100 100 100 100 100 100 98.8

MSSCVC15-B 90 100 100 100 100 90 90 100 96.2

MSSCVC15-C 100 100 100 100 90 90 100 100 97.5

MSSCVC15-D 100 100 100 100 100 100 100 100 100

MSSCVC15-E 90 100 100 100 100 100 100 80 96.2

PI-REF15-A 100 90 100 100 100 90 90 80 93.8

PI-REF15-B 100 100 100 100 100 100 100 80 97.5

Table 10. Chironomus dilutus Survival in the Miners Slough Spur Channel Sediments.

Sediment Site % Survival in Test Replicates Mean

% SurvivalRep A Rep B Rep C Rep D Rep E Rep F Rep G Rep H

Lab Control 70 80 100 100 100 100 90 90 91.2

MSSCVC15-A 100 100 100 100 100 100 100 100 100

MSSCVC15-B 100 100 90 100 70 100 80 80 90

MSSCVC15-C 100 80 90 80 80 90 80 70 83.8

MSSCVC15-D 100 100 90 100 100 80 100 90 95

MSSCVC15-E 100 80 90 100 70 100 100 90 91.2

PI-REF15-A 90 100 100 100 100 100 100 100 98.8

PI-REF15-B 100 100 100 100 100 100 100 100 100

43

Table 11. Replicate and Mean Survival Results and Median Lethal Concentrations for the 96-Hour Acute Standard Elutriate Suspended Particulate-Phase Toxicity Tests Using Fathead Minnows.

Elutriate Concentrations

Percent Survival at 96 Hours LC50 (%) Rep A Rep B Rep C Rep D Rep E Mean

MSSCVC15-A Lab Control 80 100 90 100 100 94

>100%

Site Water 80 100 90 100 100 94 1% 90 90 100 100 90 94 5% 100 100 100 100 100 100 10% 100 90 100 100 100 98 50% 80 100 90 100 90 92

100% 90 100 100 100 90 96 MSSCVC15-B

Control 100 100 100 100 100 100

>100

Site Water 80 100 90 100 100 94 1% 100 100 100 100 100 100 5% 100 90 100 100 100 98 10% 100 90 100 100 90 96 50% 90 100 100 90 100 96

100% 90 100 100 100 100 98 MSSCVC15-C

Lab Control 100 100 100 100 100 100

>100

Site Water 80 100 90 100 100 94 1% 100 100 100 100 100 100 5% 100 100 100 100 100 100 10% 90 100 100 100 100 98 50% 80 100 100 100 100 96

100% 100 90 100 100 100 98 MSSCVC15-D

Lab Control 100 100 100 100 100 100

>100

Site Water 80 100 90 100 100 94 1% 100 100 100 100 100 100 5% 100 100 100 100 100 100 10% 100 100 100 100 100 100 50% 100 100 100 100 100 100

100% 100 100 90 100 100 98 MSSCVC15-E

Lab Control 100 100 100 100 100 100

>100

Site Water 100 100 100 100 100 94 1% 100 100 100 100 100 100 5% 100 100 100 100 100 100 10% 100 100 80 100 100 96 50% 100 100 90 90 100 96

100% 100 100 100 90 100 98 Bold asterisk mean values are significantly reduced compared to their respective dilution water control (lab control).

44

5.0 DISCUSSION

Subsections that follow describe chemical and biological testing results in terms of sediment and water quality screening levels and objectives for upland placement. 5.1 Sediment Observations All Miner Slough Spur Channel sediments consisted primarily of soft clayey silt (ML) with low plasticity and high water content. Sediments, for the most part, transitioned into stiffer more plastic silty clay (CL or CH) with depth. Gravel was not visually encountered in any of the core samples and some sand was observed in a few core layers. Some cores contained layers of organic or wood debris. In comparison, all surface sediments from the Prospect Island reference samples contained clayey silt (ML) or silty clay (CL), which was mostly soft, wet and contained organic matter. 5.2 Sediment Grain Size Characteristics Grain size analyses were performed on all five Miner Slough Spur Channel composite samples and the two Prospect Island reference samples. All samples contained between 25% and 36% clay and between 64% and 75% silt. Despite visual observations, there was no measurable sand in any of the composite samples. The Prospect Island reference sediments were very similar to the spur channel sediments with 30% and 34% clay and 66% and 70% silt with no sand. 5.3 Assessment of Sediment Acid Neutralization Potential to Acid Generation Potential

and Sediment pH Sediments with a low pH and a low ratio of acid neutralization potential to acid generation potential (NP:AGP) are more likely to leach metals into groundwater and/or receiving waters. A NP:AGP ratio of greater than one is necessary so that after leaching, enough neutralizing potential will remain to neutralize pH after the sediment oxidizes. In practice, a ratio of two to three is desirable to provide neutralization capacity in excess of the potential acidification associated with oxidation (CVRWQCB et al., 2002). All sediment samples had a very beneficial NP:AGP ratios of 27 to 81. This and the fact that the reference area also had beneficial NP:AGP ratios (18 and 20) and most sediment pH values were near neutral (6.65 to 7.71), it appears unlikely that metals in the Miner Slough Spur Channel sediments will mobilize. 5.4 Cation Exchange Capacity Cation exchange capacity (CEC) is the total capacity of sediments/soils to hold onto exchangeable cations. Generally, sediments/soils with a CEC greater than 10 meq/100g) are preferred for plant production and are less likely to exhibit nutrient loss through leaching (http://www.dpi.nsw.gov.au/agriculture/resources/soils/structure/cec). The Miner Slough Spur Channel sediments have CEC values ranging from 14.8 to 25.6 meq/100g compared to 51.6 and 49.0 meq/100g for the Prospect Island reference soils.

45

5.5 Miner Slough Channel Sediment Pollutant Chemical Analyses The following conventional analyses, inorganic constituents and organic compounds were not detected in any of the composite samples and will not be discussed any further:

dissolved sulfides; TRPH; boron; chromium VI; all organochlorine pesticides except for DDT compounds; butyltins; organophosphate pesticides; and PCB Aroclors.

The detected Miner Slough Spur Channel sediment chemistry concentrations were compared to two types of sediment quality screening values as described in Section 3.2. First the results were compared to toxicity effects screening values that give a rough indication if the sediments would cause adverse biological effects to benthic organisms that may colonize the sediments once they are placed on Prospect Island and become intertidal habitat. The second set of screening values are from the DDRS and give a general indication as to whether the sediments after placement may have an effect on terrestrial animals and plants if the sediments are graded into terrestrial habitat. Results were also compared to mean sediment Delta background concentrations summarized in the DDRS to determine if the Miner Slough sediments were elevated above mean background concentrations. In addition to these screening values, a discussion is provided throughout that compares the Miner Slough Spur Channel sediments to the Prospect Island reference sediments to see if the sediments will elevate existing levels of chemical constituents already on the placement area of the Island. 5.5.1 Comparisons to Published Toxicity Effects Data Toxicity effects screening values (Buchman, 2008) are separated into values that rarely cause adverse biological effects (TELs and TECs) and values that often cause adverse biological effects (PELs and PECs). Except for nickel in all composite samples as well as the two reference composite samples, there were no chemical constituents that exceeded a PEL or PEC value (Table 6). Nickel was well above the PEL and PEC values in all samples. The following constituents exceeded one or both of the lower TEL or TEC values:

Cadmium slightly exceeded its corresponding TEL value in the A and B composite samples but were below the corresponding TEC value.

Copper exceeded the TEL and/or TEC values in all Miner Slough Channel composite samples as well as the two Prospect Island reference composite samples.

Mercury exceeded both the TEL and TEC values in the A and B composite samples. Manganese had a similar concentration to its corresponding TEL value in the D composite

sample. Composite samples for Areas A, B, C and E as well as the two Prospect Reference samples

had 4.4' DDT concentrations that exceeded corresponding TEC and/or TEL values. Total

46

DDTs exceeded corresponding TEC and/or TEL values in the Prospect Island reference composite samples but not the Miner Slough Spur Channel composite samples.

The PAH compounds benzo (k) fluoranthene and indeno (1,2,3-c,d) pyrene exceeded its corresponding TEL and/or TEC values in the A and B composite samples. Benzo(k)fluoranthene also exceeded the TEC value in the B reference composite sample.

Both high molecular weight PAHs and total PAHs exceeded the corresponding TEL values in the A and B composite samples but not in the Prospect Island reference composite samples. High molecular weight PAHs also exceeded its corresponding TEL value in the C composite sample.

Overall, it appears that the Miner Slough sediments will not substantially increase the probability of adverse biological effects to benthic organisms over the soils already existing at the placement area on Prospect Island. 5.5.2 Comparisons to DDRS Screening Values DDRS screening values used are conservative estimates based on literature sources for the protection of terrestrial plants and animals. The metals Al, Ba, Cr, Co, Cu, Mn, Hg, Ni, TL, and Zn exceeded one or both of the plant and animal screening values (Table 6). There were no organic compounds that exceeded a plant and animal screening value. If a Miner Slough Spur Channel composite sample exceeded a plant and/or animal metals screening value, in all cases the same screening value was also exceeded in one or both of the Prospect Island reference composite samples. Because of this and despite the fact that aluminum was magnitudes higher than DDRS plant and animal screening values, there appears to be no increased threat to terrestrial plants and animals by placing the Miner Slough Spur Channel sediments on Prospect Island. Mean sediment concentrations between riverine, shipping channels and marinas of the Delta reported in the DDRS were also used as screening values. If the concentration of a chemical constituent exceeded a mean Delta sediment concentration and was less than 1.2 times higher than that concentration, it was considered equal to that concentration for the purpose of this evaluation. Chemical constituents that exceeded a mean Delta sediment concentration by more than 1.2 times are described as follows:

Aluminum in all five composite samples Barium in composite samples C and D. Beryllium in all five composite samples. Chromium in all five composite samples. Cobalt in all five composite samples. Copper in composite samples A, B and C. Lead in composite sample B. Nickel in all composite samples. Vanadium in all but the E composite sample. Zinc in all composite samples. Benzo (e) pyrene in composite samples A, B and C. Benzo (g, h, i) perylene in the A composite sample. Indeno (1, 2, 3- c, d) pyrene in the A composite sample.

47

Pyrene in the A composite sample. Of the chemical constituents that were 1.2 times higher than mean Delta sediment concentrations in the Miner Slough Spur Channel composite samples, all but benzo (g, h, i) perylene, indeno (1, 2, 3- c, d) pyrene, and pyrene also exceeded the mean Delta sediment concentrations in the two Prospect Island reference composite samples. 5.5.3 Overall Comparisons to Prospect Island Placement Area Soil Concentrations So far, the Miner Slough Spur Channel sediments have only been discussed with reference sediment concentrations in terms of similar exceedances of NOAA biological effects, DDRS terrestrial biological effects and Delta mean sediment concentrations. In most cases, when a Miner Slough Spur Channel sediment concentration exceeded a screening value, the same screening value was exceeded in one or both of the Prospect Island reference composite samples. There are several instances though where the Miner Slough Spur Channel sediment concentrations exceeded like concentrations in Prospect Island reference composite samples but did not exceed any screening values. In all cases, as shown on Table 6, these exceedances appear to be minor. 5.6 DI-WET Chemical Analyses Metals leaching from subsequent precipitation and tidal flooding is a primary concern after placement of the Miner Slough Spur Channel sediments on Prospect Island. The leaching of metals can effect both groundwater and receiving water quality. The DI-WET analyses provide an estimate to the degree of these impacts. Soluble aluminum, barium, copper, lead and manganese in the DI-WET extracts exceeded one or more water quality criteria (Table 8). Aluminum in all composite extracts, barium in the D and E composite extracts, copper in the A and E composite extracts, lead in the A and E composite extracts, and manganese in the A, B, C and E composite extracts exceeded draft General Waste Discharge Requirements (WDRs) for the reuse of sediment (levee improvement) for medium scale dredging operations in the Sacramento-San Joaquin Delta. Note though that the WDRs are proposed and have no regulatory restrictions. Copper in the A and E composite samples also exceeded the acute water quality objective specified in the California Toxics Rule (CTR) for the protection of aquatic life. Lead exceeded the chronic CTR objective in the A, B and E composite samples. The copper and lead CTR objectives were based on an average hardness value of 45 mg/L CaCO3. Other than manganese, there were no soluble metals that exceeded drinking water MCLs. Manganese exceeded the secondary MCL for the protection against taste and odor. 5.7 Sediment Solid Phase Bioassay Testing Despite some sediment concentrations exceeding NOAA biological effects screening criteria, there was no significant toxicity in any of the Miner Slough sediment composite samples compared to Prospect Island reference samples and laboratory control samples with either the 10-day amphipod (Hyalella azteca) or 10-day larval midge (Chironomus dilutus) bioassays (Tables 9 and 10). Amphipod survival in the Miner Slough Spur Channel composite samples ranged from 96.2% to 100% compared to 93.8% and 97.5% in the Prospect Island reference composite samples and

48

97.5% in the laboratory control sample. Larval midge survival in the Miner Slough Spur Channel composite samples ranged from 83.8% to 100% compared to 98.8% and 100% in the Prospect Island reference composite samples and 91.2% in the laboratory control sample. 5.8 SET/SPP Chemical Analyses and Bioassay Testing To get a conservative indication as to whether sediments that may get suspended during dredging operations will effect water quality, standard elutriate test (SET) extracts were prepared from the Miner Slough Spur Channel composite samples and analyzed for a host of chemical constituents and tested for toxicity. The results were evaluated against water quality objectives. The vast majority of organic compounds were not detected in the SET extracts. The only organic compounds detected were low levels of a few PAH compounds in the SET extracts from the C composite sample, and methylmercury in all but the SET extract from the E composite sample. There are no water quality objectives for the detected PAHs available. There are also no CTR criteria for the protection of aquatic life, nor maximum Basin Plan water concentrations for methylmercury. The only Basin Plan criteria for methylmercury are for fish tissue concentrations. Only dissolved zinc in the SET extract from the A composite sample exceeded a CTR criterion for the protection of aquatic life. The only inorganic constituents that exceeded maximum levels specified in the Basin Plan or surface water quality objectives summarized in the DDRS were aluminum, barium and manganese for all composite samples and zinc for the A composite sample. Background water metal concentrations did not exceed any water quality criteria. It will take a dilution factor of about three to bring barium below water quality objectives in all composite areas, it will take a dilution factor of about 3.5 to bring aluminum levels below water quality objectives in all composite areas, and it will take a dilution factor of about six to bring manganese levels to a levels below water quality objectives in all composite areas. It will take a dilution factor of about 1.5 to bring zinc below water quality objectives in the A composite area. Despite the fact that a few inorganic constituents exceeded water quality objectives, the 100% concentrations of SET extracts were not toxic to Fathead Minnows (Pimephales promelas). Mean survival in the 100% elutriate extracts from all composite samples ranged from 96% to 98% compared to 94% in site water. Therefore, the Basin Plan objective of no toxicity was met. 5.9 Conclusions Despite the fact that some sediment concentrations in the Miner Slough Spur Channel composite samples exceeded sediment screening values for adverse biological effects to benthic organisms as well as to screening values for terrestrial plants and animals, the sediments showed no toxicity to benthic organisms and references concentrations for the most part exceeded the same objectives. Therefore there is little evidence that the Miner Slough Spur Channel sediments, from a non-water quality aspect, will degrade the soils already present on Prospect Island within the placement area. DI-WET analyses suggest that leachate impacts to surface waters or groundwater could be problematic. Water quality goals, especially dredge material reuse limits listed in draft Regional Board Waste Discharge Requirements (WDRs) for medium sized dredge projects, were exceeded

49

for several metals, especially for aluminum and manganese, though as noted previously, these WDRs are proposed and have not been promulgated. Site-specific natural attenuation factors may need to be assessed to determine the significance of these exceedances. Natural attenuation factors include physical, biological and chemical processes that can reduce the mass, concentration and mobility of metals (Wilkin, 2008). Neutralization, absorption, and mineral precipitation are some of these processes. Results do show that the sediments have a high neutralization potential and a sufficient CEC to aid in attenuation. Standard elutriate testing did show also that water quality objectives could be exceeded directly at the dredge site with no dilution for aluminum, barium and manganese in all areas and zinc in the Area A. However, it would only take a dilution factor of about six to bring all concentrations to below water quality objectives and the concentrations in the SET extracts most likely overestimates concentrations at the dredge site. In addition, there was no evidence of toxicity to Fathead Minnows in the standard elutriate samples. Therefore, water quality impacts during dredging operations are predicted to be minimal.

50

6.0 QUALITY ASSURANCE/QUALITY CONTROL (QA/QC) Kinnetic Laboratories conducts its activities in accordance with formal Quality Assurance/Quality Control (QA/QC) procedures. The objectives of the QA/QC Program are to fully document the field and laboratory data collected, to maintain data integrity from the time of field collection through storage and archiving, and to produce the highest quality data possible. Quality assurance involves all of the planned and systematic actions necessary to provide confidence that work performed conforms to contract requirements, laboratory methodologies, state and federal regulation requirements, and corporate Standard Operating Procedures (SOPs). The program is designed to allow the data to be assessed by the following parameters: Precision, Accuracy, Comparability, Representativeness, and Completeness. These parameters are controlled by adhering to documented methods and SOPs, and by the analysis of QC samples on a routine basis. 6.1 Field Sampling Quality Management Field QC procedures are summarized in Table 12 and include adherence to SOPs and formal sample documentation and tracking. SOPs for vibracore sampling and grab sampling are provided in Appendix A.

Table 12. Quality Control Summary for Field Sediment Sampling.

Sediment Sampling Field Activity Vibracore Sampling SOP Grab Sampling SOP Protocol Cleaning/Low Detection Limits Certified Clean Laboratory Containers Horizontal and Vertical Controls Core Logging & Subsampling Protocols Sample Control/ Chain of Custody Procedures Field Logs and Core Logs Sample Preservation & Shipping Procedures

6.2 Chemical Analyses Quality Management Analytical chemistry QC is formalized by USEPA and State Certification agencies, and involves internal quality control checks such as method blanks, matrix spike/spike duplicates, duplicates, surrogates and calibration standards. Any issues associated with the quality control check are summarized in Appendix E. Eurofins laboratory reports in Appendix C provide Case Narratives for the laboratory analyses. QA/QC findings presented are based on the validation of the data according to laboratory quality assurance objectives and using guidance from USEPA National Functional Guidelines for inorganic and organic data review (USEPA, 2014a and 2014b). As the first step in the validation process, all results were carefully reviewed to check that the laboratories met project reporting limits. With a few exceptions, as described in Appendix E, project reporting limits were met. Elevated reporting limits for sediments mostly resulted after dry weight adjustment of the results. Method blank results are a good indicator of project limits

51

being achieved, as they are not dry weight adjusted. The only sediment constituent that exceeded the RL in the method blank was molybdenum. For the water analyses, both toxaphene and hexavalent chromium exceeded target reporting limits. Another initial step was to determine if chemical analyses were completed within holding times. Most sediment and water analyses were initialized within EPA hold times. Sediment and water pH was initiated late since this is a parameter that should be measured right away. Sediment total sulfides were also initiated out of hold time but the samples were frozen prior to analysis, which extends the hold time. QA/QC records (1,401 total) for the sediment and water chemical analyses included method blanks, laboratory duplicates, laboratory control samples (LCS) and their duplicates, blank spikes (BS) and blank spike duplicates, matrix spikes (MS) and matrix spike duplicates, post digestion spikes (PDS) and their duplicates, and surrogate (SURR) analyses. Total numbers of QC records by type are summarized in Table 13. Data, for the most part, were shown to be both accurate and precise and free of contamination. Only 2.1% of the total number of sample values (40 total) required qualification based on professional judgment. Those analytes requiring qualification and the resulting qualifiers are summarized in Table 14. Of those 40 qualified results, 28 were for sediment samples due to low matrix spike recoveries, 10 were for DI-WET samples and were caused by both low matrix spike recoveries and method blank detections, and two were from the SET extracts due to both low laboratory control sample recoveries, matrix spike recoveries and method blank detections. The details of the entire review are provided in Appendix E. Results support that overall evaluation of the analytical QA/QC data indicates that the chemical data are for the most part within established performance criteria and can be used for characterization of Miner Slough Spur Channel sediments.

52

Table 13. Counts of QC records per Chemical Category. Sediment

Conventionals Percent Solids 1 2 3 pH 2 2 Ammonia 1 2 3 Cation Exchange Capacity 1 1 2 4 Dissolved Sulfides 1 1 2 4 Total Sulfides 1 1 2 4 Total Organic Carbon 1 2 2 5 Oil & Grease 1 2 3 TRPH 1 2 3 Methylmercury 3 1 2 2 8

Total Metals 21 41 42 19 123

Chlorinated Pesticides 29 40 40 16 125

Butyltins 4 2 4 8 18

PCB Aroclors 8 2 4 16 30

PAH’s 50 16 32 54 152

Organophosphate Pesticides 20 16 32 8 76

Sediment Totals 143 7 132 160 19 102 563

Water Conventionals Ammonia 2 4 2 8 Chloride 2 2 4 8 Total Suspended Solids 2 2 4 8 Total Dissolved Solids 3 3 6 12 pH 3 3 Specific Conductance 1 1 BOD 2 2 4 COD 2 2 2 6 DOC 1 2 2 5 Hardness 3 3 6 Oil & Grease 2 4 2 8 Methylmercury 9 3 8 10 30 Total and Dissolved Metals 63 70 54 187 Organochlorine Pesticides 60 60 40 32 192

Speciated butyltins 8 6 4 8 26 PCB Aroclors 14 6 4 16 40 PAH’s 50 54 36 24 164

Organophosphate Pesticides 42 48 32 8 130

Water Totals 265 19 276 190 0 88 838

53

Table 14. Final QC Qualification Applied to Sample Results.

Analyte # Samples Qualified

Final Qualifier

BLK DUP LCS/BS

MS PDS SURR

Sediment - Metals

Antimony 7 J- J-

Sediment – OC Pesticides

4,4’-DDT 7 J- J-

Endrin 7 J- J-

Endrin Ketone 7 J- J-

DI-WET – Metals

Antimony 5 J U/J+ J-

Silver 5 J- J-

SET – Methylmercury 1 J+ J+

SET – Methylmercury 1 J- J- J-

Total number of affected samples 40

Percentage of all samples 2.1%

5.3 Biological Testing Quality Management Quality assurance procedures employed for this project were consistent with the procedures detailed in the OTM. Sediments used for biological testing were stored at ≤4 C and were used within the eight-week holding time. Summary bioassay and bioaccumulation testing and quality assurance information is provided in the bioassay report (Appendix D). This appendix includes documentation of: 1) test animal collection, shipping and holding/acclimation, 2) water quality parameters monitored during the test, and 3) the positive (reference toxicant) control. Negative control performance is included in the bioassay report. Data quality objectives and the associated quality control measures for aquatic toxicity testing are stipulated in the specified bioassay protocols. Such measures include test temperatures and acceptable limits of variation, minimum acceptable dissolved oxygen levels with aeration and/or renewal procedures to be used if required, and acceptable pH range to be employed. Upon receipt, the sediments were centrifuged and the resulting porewater was measured for pH, conductivity, total ammonia and total sulfide. These data are provided in Table 15. Additional measurements of hardness, conductivity, alkalinity, ammonia and sulfides were required for all bioassays at test initiation. These measurements were made on a composite of an aliquot of overlying water from each test chamber for the SP bioassays and from each treatment test solution for the SPP bioassays. Dissolved oxygen and temperature were measured daily in the overlying water or directly from each elutriate concertation from randomly selected test replicates or treatments and adjusted accordingly. A schedule of monitoring these environmental parameters is usually provided with each protocol, and bioassay results must include these monitoring data. All interstitial and overlying water quality measurements at the beginning and during biological testing were within appropriate limits. All instrument calibrations were properly logged and initialed.

54

Table 15. Initial Porewater Quality Measurements.

Sample ID pH Conductivity

(µS/cm) Total Ammonia

(mg/L N) Total Sulfide

(mg/L) MSSCVC15-A 7.28 553 13.1 0.023 MSSCVC15-B 7.30 395 9.5 0.088 MSSCVC15-C 7.27 458 6.09 0.047 MSSCVC15-D 7.37 411 4.63 0.139 MSSCVC15-E 7.28 335 3.07 0.044 PI-REF15-A 7.16 291 2.01 0.356 PI-REF15-B 7.04 380 3.10 0.508

Protocols also provide guidance on test organisms procurement, care and acclimation. Pacific EcoRisk maintains laboratory logbooks documenting these factors. Organism assignment to test tanks and test tank positioning in the laboratory are randomized. Feeding is conducted according to protocol. Another important bioassay QA measure is the inclusion of an experimental control where organisms are simultaneously exposed to laboratory test conditions in the absence of a toxicant stress. Biological responses for all test organisms in the negative control treatments met test acceptability criteria (TAC) for both the SP and SPP bioassays with greater than 90% mean survival in all treatments. The final bioassay QA measure is the inclusion of reference toxicant bioassays, in which the organisms are exposed to standard toxicants. Reference toxicant bioassays are run concurrently with and under the same conditions as the bioassays of the test material. Control charts are maintained in the laboratory for each species/toxicant combination. A minimum of five bioassays is required for a valid control chart, and upper and lower limits are developed, which are two standard deviations on either side of the mean. Precision is quantified in the control charts by calculation of the coefficient of variation (CV). The application of a maximum acceptable value for the CV or the minimum significant difference (MSD) increases data reliability, and many newer protocols specify such maximum acceptable values. All positive control tests exhibited “typical response” ranges and thus met TAC. Therefore, the test organisms used for this project responded to toxic stress in a typical and consistent fashion.

55

6.0 REFERENCES American Society for Testing and Materials. 2009. ASTM D 2488-09a, Standard Practice

for Description and Identification of Soils (Visual-Manual Procedure): ASTM Annual Book of Standards, Volume 04.08 on Soil and Rock, Section 4 – Construction, West Conshohocken, PA.

American Public Health Association. 2012. Standard Methods for the Examination of Water

and Wastewater. 22nd Edition, Washington, D.C. Buchman, M.F. 2008. NOAA Screening Quick Reference Tables, NOAA OR&R Report

08-1. Seattle, Washington, Office of Response and Restoration Division, National Oceanic and Atmospheric Administration, 34 pages.

California Department of Fish and Game (CDFG). 2009. California Endangered Species Act Incidental Take Permit No. 2081-2009-001-03. Department of Water Resources, California State Water Project Delta Facilities and Operations. Available: <http://www.dfg.ca.gov/delta/data/longfinsmelt/documents/ITP-Longfin-1a.pdf>. Accessed: January 15, 2015.

California Department of Water Resources and California Department of Fish and Wildlife

(DWR and CDFW). 2014. Prospect Island Tidal Habitat Restoration Project: Conceptual Restoration Plan. Final. Prepared by California Dept. of Water Resources and California Dept of Fish and Wildlife with assistance from Stillwater Sciences, Davis, California and Wetlands and Water Resources, Inc., San Rafael, California. Contract No. 4200009291. September.

California Regional Water Quality Control Board, Central Valley Region (CVRWQCB).

1989. The Designated Level Methodology for Waste Classification and Cleanup Level Determination. Staff Report. October 1986, Updated June, 1989.

CVRWQCB. 2015. Water Quality Control Plan (Basin Plan) for the Sacramento and San

Joaquin River Basins. Revised October 2011 with approved amendments. Updated June 2015.

CVRWQCB. Undated. Draft General Waste Discharge Requirements for Medium Scaled

Projects in the Sacramento-San Joaquin Delta (Draft General Order). Order No. xxxx.

California Regional Water Quality Control Board, Central Valley Region (CVRWQCB),

California Department of Fish and Game, and Delta Protection Commission. 2002. Delta Dredging and Reuse Strategy. Volumes I and II. June. Sacramento, CA.

Kinnetic Laboratories, Inc. 2015. Sampling and Analysis Plan. Evaluation of Miner Slough

Spur Channel Dredge Material, Prospect Island Tidal Habitat Restoration Project. Pre pared for the CA Dept. of Water Resources. February 2015.

56

Krone CA, Brown, DW, Burrows, DG, Chan, S-L, Varanasi, U. 1989. Butyltins in sediment

from marinas and waterways in Puget Sound, Washington State, U.S.A. Mar Poll Bull 20:528-31.

MacDonald, D.D., C.G. Ingersoll, and T.A. Berger. 2000. Development and evaluation of consensus based sediment quality guidelines for freshwater ecosystems. Arch. Environ. Contam. Toxicol 39: 20-31.

National Marine Fisheries Service (NMFS). 2009. Biological opinion and conference

opinion on the long-term operations of the Central Valley Project and the State Water Project. Prepared for U.S. Bureau of Reclamation. National Marine Fisheries Service, Southwest Region, Long Beach, CA. June 4.

Plumb, R.H., Jr., 1981. Procedures for Handling and Chemical Analysis of Sediment and

Water Samples. Environmental Laboratory. Technical Report. EPA/CE-81-1. U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS.

Sobek, A.A. et. al., 1978. Field and Laboratory Methods Applicable to Overburdens and

Mine Soils. Report-West Virginia University. Prepared for U.S. Environmental Protection Agency, Office of Research and Development, Industrial Environmental Research Laboratory. Cincinnati, OH. Grant No. R803508-01-0.

State Water Resources Control Board. 2005. Policy for Implementation of Toxics Standards

for Inland Surface Waters, Enclosed Bays, and Estuaries of California. Revised February, 2005.

United States Army Corps of Engineers (USACE). 1987. Confined Disposal of Dredged

Material. Engineer Manual 1110-2-5027. Office, Chief of Engineers, U.S. Army Corps of Engineers. Washington, D.C.

USACE. 2003. Evaluation of Dredge Material Proposed for Disposal at Island, Nearshore,

or Upland Disposal Facilities – Testing Manual (UTM). ERDC/EL TR-03-1. January 2003.

United States Environmental Protection Agency (USEPA), 1994. Methods for Measuring

the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms. 4th Edition. EPA/600/4-91-002.

USEPA. 2000a. Water Quality Standards; Establishment of Numeric Criteria for Priority

Toxic Pollutants for the State of California; Rule. Federal Register, 40 CFR Part 131. USEPA. 2000b. Methods for Measuring the Toxicity and Bioaccumulation of Sediment-

Associated Contaminants with Freshwater Invertebrates. Second Edition. U.S. Environmental Protection Agency Office of Water (4305). EPA-600/R-99/064.

57

USEPA. 2001. USEPA Contract Laboratory Program, National Functional Guidelines for

Low Concentration Organic Data Review. EPA540-R-00-006. USEPA. 2002a. Methods for Measuring the Acute Toxicity of Effluents and Receiving

Waters to Freshwater and Marine Organisms. Fifth Edition. U.S. Environmental Protection Agency Office of Water (4303T). EPA-821-R-02-012.

USEPA. 2002b. National Recommended Water Quality Criteria: 2002. EPA-822-R-02-047.

Office of Science and Technology. November 2002. USEPA. 2003. Ambient Aquatic Life Criteria for Tributyltin (TBT) - Final. EPA 822-R-

03-031. USEPA. 2014a. National Functional Guidelines for Superfund Organic Methods Data

Review. EPA540-R-014-002. August 2014. USEPA. 2014b. National Functional Guidelines for Inorganic Superfund Data Review. EPA

540-R-13-001. August 2014. U.S. Environmental Protection Agency/U.S. Army Corps of Engineers (USEPA and

USACE). 1998. Evaluation of Dredged Material Proposed for Discharge in Waters of the United States – Inland Testing Manual. EPA-823-B-98.

U.S. Fish and Wildlife Service (USFWS). 2008. Formal Endangered Species Act

consultation on the proposed Coordinated Operations of the Central Valley Project (CVP) and State Water Project (SWP). Biological opinion. Prepared by USFWS, California and Nevada Region, Sacramento, CA. Available: <http://www.fws.gov/sfbaydelta/cvp-swp/cvp-swp.cfm>. Accessed: January 15, 2015.

Wilkin, RT. 2008. Contaminant Attenuation Processes at Mine Sites. Mine Water Environ

27:251-258.

sampling and analysis report - water.ca.gov · 1.2 project summary ... 5.3 assessment of sediment...

Documents