Appendix-Marina_del_Rey_Geotechand_Evironmental_Report_July2016.pdf

FINAL SAMPLING AND ANALYSIS PLAN REPORT

Marina del Rey Harbor Geotechnical and Environmental Investigation Project

Task Order No. 0012, USACE Contract No. W912PL-11-D-0015

Prepared for:

U.S. Army Corps of Engineers

Los Angeles District Los Angeles, California

Prepared by:

DiazYourman – GeoPentech – Kinnetic Laboratories/ Joint Venture 1616 E. 17th Street

Santa Ana, CA 92705

July 2016

GeoPentech i

DISTRIBUTION LIST

Mr. Jeffrey Devine, Technical Manager U. S. Army Corps of Engineers, Los Angeles District Jeffrey.D.Devine@usace.army.mil

Ms. Kelly Shaw Field Geotechnical Leader Diaz Yourman Kelly Shaw <Kelly@diazyourman.com>

Larry Smith, Technical Manager U. S. Army Corps of Engineers, Los Angeles District Lawrence.J.Smith@usace.army.mil

Mr. Christopher Diaz Geotechnical Manager Diaz Yourman & Associates chris@diazyourman.com

Mr. Jeffrey Cole, Project Manager U. S. Army Corps of Engineers, Los Angeles District Jeffrey.Cole@usace.army.mil

Mr. Allen Yourman Joint Venture Project Manager Diaz Yourman Associates, GeoPentech, and Kinnetic Laboratories Joint Venture Allen@diazyourman.com

Mr. Michael Lyons Los Angeles Regional Water Quality Control Board Michael.Lyons@waterboards.ca.gov

Mr. Ken Kronschnabl KLI Project Manager Kinnetic Laboratories, Inc.

kkronsch@kinneticlabs.com

Ms. Melisa Scianni United States Environmental Protection Agency- Region 9 scianni.melissa@epa.gov

Mr. Spencer Johnson Field Operations Manager Kinnetic Laboratories, Inc.

sjohnson@kinneticlabs.com

Mr. Allan Ota United States Environmental Protection Agency- Region 9 ota.allan@epa.gov

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

ahowk@kinneticlabs.net

Mr. Larry Simon Federal Consistency Coordinator Energy, Ocean Resources and Federal California Coastal Commission lsimon@coastal.ca.gov

Mr. Jon Toal Health and Safety Management Kinnetic Laboratories, Inc.

jtoal@kinneticlabs.com

Carla Hollowell Client Services Director Eurofins Calscience CarlaHollowell@eurofinsUS.com ii

Marina del Rey Harbor Geotechnical and Environmental Investigation

Project

Task Order No.0009, USACE, Contract No. W912PL-11-D-0015

TABLE OF CONTENTS

Page No.

1.0 INTRODUCTION

1.1 Project Summary

1.2 Site Location

1.3 Roles and Responsibilities

2.0 HISTORICAL DREDGING AND DATA REVIEW

3.0 METHODS

3.1 Dredge Design

3.2 Study Design

3.2.1 Marina del Rey Harbor Sediment Collection and Testing

3.2.2 Dockweiler State Beach Reference Samples

3.2.3 Geotechnical Samples and Testing

3.2.4 Summary of Marina del Rey Harbor Testing and Evaluation Sequence

3.2.5 Evaluation Guidelines

3.3 Field Sampling Protocols

3.3.1 Positioning and Depth Measurements

3.3.2 Vibracore Sampling Methods

3.3.3 Vibracore Decontamination

3.3.4 Core Processing

3.3.5 Beach Transect and Nearshore Area Grab Samples

3.3.6 Detailed Soils Log

3.3.7 Documentation and Sample Custody

3.4 Laboratory Testing Methods

3.4.1 Geotechnical Testing

3.4.2 Bulk Sediment Chemical Analyses

4.0 RESULTS

4.1 Sediment Physical Results

4.2 Sediment Chemical Results

5.0 DISCUSSION

5.1 Sediment Observations

5.2 Sediment Grain Size

5.3 Bulk Sediment Chemistry

6.0 QUALITY CONTROL SUMMARY

6.1 Field Sampling Quality Management

6.2 Analytical Chemistry QA/QC

7.0 REFERENCES CITED

iii

APPENDICES

APPENDIX A – Previous Testing Data (Kinnetic Laboratories and Halcrow, 2010 and 2011) APPENDIX B – Beach Physical Compatibility Analysis (USACE, Los Angeles District, 2016) APPENDIX C – Core Photographs APPENDIX D – Soil Logs of Sediment Physical Characteristics APPENDIX E – Analytical Laboratory Report APPENDIX F – Field Data Logs APPENDIX G – Grain Size Distribution Curves and Other Physical Data APPENDIX H – Analytical Quality Assurance/Quality Control Report

LIST OF TABLES

Table 1. Dredge Area Volume Estimates for the Entrance Channel to MDR Harbor Table 2. Project Team and Responsibilities Table 3. Key Project Contacts Table 4. Marina del Rey Harbor Dredging History Table 5. Actual Sampling Locations, Core Depths, Mudline Elevations, and Sampling

Elevations for Marina del Rey Harbor 2016 O&M Dredging Table 6. Dates, Times and Sampling Coordinates for Samples Collected from Beach

Reference Sites Table 7. Sediment Analytical Methods and Quantitation Limits Achieved Table 9. 2016 Marina del Rey Harbor Sieve Analysis Weighted Average Data for the

Individual Locations and Composite Areas Table 10. Surface Physical Data for the Nearshore Area and Beach Transects at Dockweiler

State Beach Table 11. 2016 Marina del Rey Harbor Composite Bulk Sediment Chemistry Results Table 11. 2016 Marina del Rey Harbor Composite Bulk Sediment Chemistry Results

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

LIST OF FIGURES

Figure 1. Location of Marina del Rey Harbor and Dockweiler State Beach Figure 2. 2015 Bathymetric Data and Target Sampling Locations, Marina del Rey Harbor

Entrance Channel Figure 3. Major Drainage Areas and Storm Drains into Marina del Rey Harbor Figure 4. Location of Dockweiler State Beach Transects Sampling Locations and Location of

Nearshore Placement Area Sampling Locations iv

LIST OF ACRONYMS

ASTM American Society for Testing and Materials MS Matrix Spike

BLK Method or Procedural Blank MSD Matrix Spike Duplicate

BMP Best Management Practice MSD Minimum Significant Difference

BS Blank Spike ND Not Detected

BSD Blank Spike Duplicate NOAA National Oceanic and Atmospheric Administration

Cal/EPA California Environmental Protection Agency OEHA Office if Environmental Hazard Assessment

CD Compact Disc OTM Ocean Testing Manual

CDFG California Department of Fish and Game PAH Polyaromatic Hydrocarbon

CESPD Corps of Engineers South Pacific Division PCB Polychlorinated Biphenyl

CHHSL California Human Health screening Level PDS Post Digestion Spike

COC Chain of Custody PDSD Post Digestion Spike Duplicate

CSLC California State Lands Commission PPB Parts Per Billion

CV Coefficient of Variation PPM Parts Per Million cy Cubic Yards PRG Preliminary Remediation Goals

CRM Certified Reference Material PVC Polyvinyl Chloride

DDD Dichlorodiphenyldichloroethane QA Quality Assurance

DDE Dichlorodiphenyldichloroethylene QC Quality Control

DDT Dichlorodiphenyltrichloroethane QUAL Qualifier

DGPS Differential Global Positioning Satellite RBC Risk-Based Concentration

DTSC Department of Toxic Substances Control RL Reporting Limit

DUP Laboratory Replicates RPD Relative Percent Difference

ERL NOAA Effects Range Low RSLs Regional Screening Levels for Cleanup of Superfund Sites

ERM NOAA Effects Range Medium

SC-

DMMT

Southern California Dredge Material Management Team

GPS Global Positioning Satellite SOPs Standard Operating Procedures

HHMSSL

Human Health Medium – Specific Screening Levels

SRM Standard Reference Material

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

ITM Inland Testing Manual SURR Surrogate Analysis

LCL Lower Control Limit SWQCB State Water Resources Control Board

LCS Laboratory Control Spike TOC Total Organic Carbon

LDPE Low-density Polyethylene TRPH Total Recoverable Hydrocarbons

LPC Limiting Permissible Concentration TTLC Title 22 Total Threshold Limit Concentration

LSD Least Significant Difference UCL Upper Control Limit

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

MDR Marina del Rey USEPA U.S. Environmental Protection Agency

MLLW Mean Lower Low Water USCS Unified Soil Classification System v

EXECUTIVE SUMMARY

The United States Army Corps of Engineers (USACE) needs to conduct routine maintenance dredging in a portion of the federal Entrance Channel to Marina del Rey Harbor (Figure 1). Marina del Rey Harbor requires dredging every few years to keep the Entrance Channel open. Based on a March 2016 bathymetric survey, up to 432,000 cubic yards (cy) of sediment with a two-foot overdepth allowance are being evaluated for this testing round. The entire Entrance Channel has been historically divided up into 12 separate dredge areas (Figure 2). However, the 432,000 cy of sediment to be removed is restricted to Areas 4, 5, 6 and 7N. The authorized dredge depth for Areas 4, 5 and 7N is -20 feet Mean Lower Low Water (MLLW). Area 6 is authorized to -20 feet MLLW with an advanced maintenance dredging allowance to -30 feet MLLW in order to trap sand deposited by longshore currents. Sediments from the four channel/dredge areas were last evaluated in 2010. Historically, the sediments from Areas 4, 5, 6 and 7N have been suitable for aquatic placement offshore of Dockweiler State Beach (Figure 1).

Vibracore sampling was conducted from the 35-foot vessel the DW Hood to collect subsurface sediment samples at 18 locations throughout the four dredge areas. Due to the lack of shoaling above the authorized dredge depth in Area 7N that was discovered during the field investigation, Area 7N was dropped from this testing program and not sampled. Therefore, only 13 locations amongst three dredge areas were sampled, and the volume of sediments evaluated dropped to 407,000 cy with a two-foot overdepth allowance. Sampling was conducted on April 12, 2016.

Subsamples from each of the 13 locations were combined with like subsamples from a channel/dredge area to form three composite samples representing the three dredge areas. These composite samples were analyzed for total and volatile solids, total organic carbon, oil & grease, petroleum hydrocarbons, ammonia, sulfides, metals (arsenic, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver and zinc), butyltins, pyrethroid pesticides, chlorinated pesticides, PCB congeners, phenols, phthalates, and PAH compounds. Several gallons or the composite sample was also archived for potential toxicity testing. In addition, samples for grain size analyses and for chemical archiving were collected from each individual core prior to compositing. These grain size and archive samples represented the entire core length from the top of the core to the two-foot overdepth elevations. Additional grain size samples were collected from any distinct vertical grain size stratum. Furthermore, several gallons from each composite sample has been archived in case solid phase bioassay testing is requested.

Additional surface samples (top six inches) were collected from the Dockweiler State Beach onshore and nearshore placement areas on April 13, 2016. Samples at eight locations spread out between elevations of +12 and -30 MLLW were collected along three transects perpendicular to the shore and analyzed for grain size distribution. In addition, eleven random locations were sampled from the designated nearshore area (Figure 4). These samples were also analyzed individually for grain size distribution. Beach physical compatibility analysis was conducted by the USACE, Los Angeles District Geology section. This was based on comparing grain size data from grab samples collected from the beach and nearshore placement sites to that of deep continuous vibracore samples collected from the dredge footprint. The results of this analysis indicates that all of the sediments from the Areas 4, 5 and 6 dredge footprints are physically compatible for placement at both the nearshore and onshore areas of Dockweiler State Beach.

vi

In addition to the grain size samples, the eleven-nearshore area surface grab samples were combined into a single composite sample and analyzed for the same list of bulk sediment constituents analyzed for the Marina del Rey Harbor dredge sediments. Several gallons of the composite sample are also being archived as reference material for solid phase bioassay testing.

Bulk sediment chemistry results were evaluated against National Oceanic and Atmospheric Administration (NOAA) toxicity effects-based screening levels and to USEPA Region 9 and State of California human health objectives. Of the detected constituents, only DDT and chlordane compounds exceeded NOAA’s lower effects-based screening levels (ERLs) but were below upper effects-based screening levels (ERMs). Arsenic exceeded human health objectives in all three composite samples and the nearshore area reference sample. However, arsenic routinely exceeds these objectives and the concentrations found in the composite samples are similar to background concentrations for arsenic. The only other constituent to exceed a human health objective was benzo (a) pyrene, which only slightly exceeded the USEPA Region 9 screening level for residential settings.

The Marina del Rey Harbor sediment composite sample chemical results were also compared with the sediment chemical results from the Dockweiler State Beach nearshore reference area. Both inorganic and organic concentrations in the Area 6 composite sample were mostly less than concentrations in the reference sample. Metal and detected organic concentrations in the Area 4 and 5 composite samples were generally slightly higher than reference concentrations.

Marina del Rey Harbor Geotechnical and Environmental Investigation

Project

Task Order No. 0012, USACE Contract No. W912PL-11-D-0015

1.0 INTRODUCTION

Maintenance dredging is required for portions of the federal Entrance Channel to Marina del Rey (MDR) Harbor in Marina del Rey, California (Figure 1) in order to restore the channel to design depths. Sediments to be dredged require an environmental evaluation of sediment quality in order to support planning and permitting for dredging and reuse. This project is authorized by 1958 Rivers and Harbors Act (H. DOC. 356, 90TH CONG. 2nd SESS).

This Sampling and Analysis Plan Report (SAPR) has been prepared on behalf of the U.S. Army Corps of Engineers (USACE), Los Angeles District to detail procedures conducted and results obtained for the sampling and testing of sediments from MDR Harbor identified for placement at potential beach nourishment areas. This work is being performed under Task Order No. 0012, USACE Contract No. W912PL-11-D-0015. All work described in this report was conducted in accordance to the approved Sampling and Analysis Plan (Diaz-Yourman and Associates, GeoPentech and Kinnetic Laboratories Joint Venture, 2016).

1.1 Project Summary

The purpose of this project was to sample and test sediments from shoaled areas within the federal Entrance Channel proposed for maintenance dredging in order to provide sediment quality data for evaluation of dredging and beach nourishment. This SAPR is to fulfill requirements of CESPD Regulation No. 1110-1-8 (CESPD, 2000), the Inland Testing Manual (ITM) (USACE and USEPA, 1998), the Clean Water Act (CWA), and from draft guidelines developed by the Southern California Dredge Material Management Team (SC-DMMT).

The U.S. Army Corps of Engineers maintains the channel in and out of Marina del Rey Harbor.

The Entrance Channel has an authorized depth of –20 ft MLLW. Nearshore areas outside the entrance jetties are dredged to -30 feet MLLW to trap sand deposited by longshore currents. Based on a March 2016 hydrographic survey and assuming no sediment removal or shoaling has occurred, the estimated volume of sediments requiring dredging from the MDR Harbor Entrance Channel at the time of the survey was 432,000 cubic yards (cy), which includes a two-foot overdepth allowance. Figure 2 shows the bathymetric data and depicts the shoaling in the Entrance Channel. It is proposed to beneficially reuse all MDR Harbor dredge material for beach nourishment at Dockweiler State Beach, on or just offshore of the beach, (Figure 1) if physical and chemical properties of the sediments are suitable for this purpose.

For compositing and testing purposes, MDR Harbor was historically divided into 12 individual dredge areas. Only four of these dredge areas (Areas 4, 5, 6 and 7N) were proposed for dredging in 2016. Project elevations, sampling elevations and dredge volumes for each of these areas are provided in Table 1.

Figure 1. Location of Marina del Rey Harbor and Dockweiler State Beach.

Figure 2. 2015 Bathymetric Data and Target Sampling Locations, Marina del Rey Harbor Entrance Channel.

THIS PAGE WAS LEFT INTENTIONALLY BLANK

Table 1. Dredge Area Volume Estimates for the Entrance Channel to MDR Harbor.

Dredge/ Composite

Area

Project Elevation

(ft, MLLW)

Project Elevation + Overdepth

(ft, MLLW)

Sampling Elevation*

(ft, MLLW)

Volume with No Overdepth

(yd3)**

Volume with 2 ft Overdepth

(yd3)**

4 -20 -22 -22 18,000 34,000

5 -20 -22 -22 58,000 80,000 6 -30 -30 -32 293,000 293,000

7 North -20 -22 -22 5,000 25,000

TOTAL 374,000 432,000

* Sampling depth includes two feet for overdepth allowance.

**Volume Quantities based on Government survey conducted September 2015.

1.2 Site Location

Marina del Rey Harbor is located in Los Angeles County, California (Figure 1). Geographic coordinates (NAD 83) for the north side of the Entrance to MDR Harbor are 33 57.8' N and 118 27.8' W. The Dockweiler State Beach placement area is just to the south of MDR Harbor in front of the LAX International Airport. Geographic coordinates of the approximate center of the Dockweiler State Beach nourishment area are 33 56.4' N and 118 26.8' W.

The Dockweiler State Beach nearshore placement area is bounded by the following corner coordinates:

33° 56.31'N, 118° 26.75'W 33° 56.33'N, 118° 26.56'W 33° 55.94'N, 118° 26.58'W 33° 55.98'N, 118° 26.39'W

1.3 Roles and Responsibilities

Project responsibilities and key contacts for this sediment characterization program are listed in Tables 2 and 3. Kinnetic Laboratories Inc. provide sampling and reporting services. Diaz Yourman and Associates was responsible for core logging and geotechnical testing. Analytical chemical testing of sediments for this project was primarily carried out by Eurofins Calscience (Cal-ELAP No. 2944).

Table 2. Project Team and Responsibilities Responsibility Name Affiliation

Project Planning and Coordination

Jeffrey Cole Jeffrey Devine

Larry Smith Christopher Diaz Ken Kronschnabl

USACE

USACE

USACE

Diaz-Yourman Kinnetic Laboratories

Sampling and Analysis Plan (SAP) Preparation Ken Kronschnabl Christopher Diaz

Kinnetic Laboratories Diaz-Yourman

Field Sample Collection and Transport Spencer Johnson

Dale Parent Kinnetic Laboratories Kinnetic Laboratories

Geotechnical Investigation Chris Diaz Kelly Shaw

Diaz-Yourman Diaz-Yourman

Health and Safety Officer and Site Safety Plan Jon Toal Kinnetic Laboratories

Laboratory Chemical Analyses Carla Hollowell

Katie Scott Eurofins

Kinnetic Laboratories Biological Testing Jeffrey Cotsifas Pacific EcoRisk

QA/QC Management Analytical Laboratory QA/QC

Danielle Gonsman Amy Howk

Carla Hollowell

Kinnetic Laboratories Kinnetic Laboratories

Eurofins

Technical Review

Pat Kinney Jeffrey Devine

Christopher Diaz Larry Smith

Joe Ryan

Kinnetic Laboratories

USACE

Diaz-Yourman

USACE

USACE

Final Report Ken Kronschnabl Christopher Diaz

Kinnetic Laboratories Diaz-Yourman

Agency Coordination Jeffrey Devine

Lawrence Smith

USACE

USCAE

Table 3. Key Project Contacts Jeffrey Cole USACE Project Manager PPMD Navigation and Coastal Projects Branch U. S. Army Corps of Engineers, Los Angeles

District 915 Wilshire Blvd.

Los Angeles, Ca. 90017 Tel. (213) 452-3388.

Jeffrey.Cole@usace.army.mil

Jeffrey Devine USACE Project Technical Manager Geology and Investigations Section U. S. Army Corps of Engineers, Los Angeles District 915 Wilshire Blvd.

Los Angeles, Ca. 90017 Tel. (213) 452-3579 Jeffrey.D.Devine@usace.army.mil

Larry Smith USACE Project Technical Manager U. S. Army Corps of Engineers, Los Angeles District 915 Wilshire Blvd.

Los Angeles, Ca. 90017 Tel. (213) 452-3876 Kirk.C.Brus@usace.army.mil

James Farley USACE’s Contracting Officer representative U. S. Army Corps of Engineers, Los Angeles District 915 Wilshire Blvd.

Los Angeles, Ca. 90017 Tel. (213) 452-3575 James.A.Farley@usace.army.mil

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

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

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

Spencer Johnson Field Operations Mgr.

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

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

Michele Castro Buisiness development Manager Eurofins Calscience, Inc.

7440 Lincoln Way Garden Grove, CA 92841-1427 Tel.: (949) 870-8766 MicheleCastro@eurofinsUS.com

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

307 Washington St.

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

Allen Yourman Joint Venture Project Manager Diaz Yourman Associates, Geopentech, and Kinnetic Laboratories Joint Venture 1616 East 17th Street Santa Ana, CA 92705-8509 Tel. (714) 245-2920 Allen@diazyourman.com

2.0 HISTORICAL DREDGING AND DATA REVIEW

Marina del Rey Harbor, located in the County of Los Angeles, is a small craft harbor constructed in the late 1950s, early 1960s and was formally dedicated in 1965. Today it is one of the largest man-made small boat harbors in the United States with 19 marinas and a capacity for 5,300 boats.

The U.S. Army Corps of Engineers has dredged during 12 different years since 1969. Dredging years, volumes and disposal/reuse sites are identified in Table 4.

Table 4. Marina del Rey Harbor Dredging History.

Date Method Volume (cubic yards) Disposal Site 1969 Hydraulic dredge 390,000 Dockweiler State Beach 1973 Hydraulic dredge 16,000 Venice Beach 1981 Hydraulic dredge 217,000 Dockweiler State Beach 1987 Hydraulic dredge 35,000 Dockweiler State Beach 1992 Dragging 21,500 In situ 1994 Clam shell 55,000 POLA CAD Site 1996 Hydraulic dredge 240,000 Dockweiler State Beach 1998 Clam shell 52,000 LA-2 1998 Clam shell 74,000 Dockweiler State Beach nearshore 1999 Clam shell 390,000 POLB Slip 3 1999 Clam shell 282,000 Redondo Beach 2007 Clam shell 327,000 Dockweiler State Beach nearshore 2009 Hydraulic dredge 2,000 Dockweiler State Beach* 2012 Clam Shell 471,000 POLB – Middle Harbor – Slip 1 2012 Clam Shell 150,000 Dockweiler State Beach nearshore 2012 Clam Shell 75,000 Redondo Beach Onshore 2012 Clam Shell 82,000 Redondo Beach Nearshore

*Sand Separation Project

Physical and chemical sampling and testing of the MDR Harbor Entrance Channel most recently occurred in 2010. A total of 60 core samples (20 from areas 4, 5, 6 and 7N) were collected to project depths plus two feet (or refusal) and analyzed for grain size distribution. Data from these analyses were compared to the grain size distribution of sediments from Dockweiler State Beach and Redondo Beach collected along three transects at each beach as well as from an offshore placement area for each beach. In addition, representative portions of the 60 cores were combined into 14 composite samples (4 above the overdepth elevation for Areas 4, 5, 6 and 7N) for bulk sediment chemical analyses to determine if the Harbor sediments were environmentally suitable for beach nourishment. Chemical analyses were also performed on the individual cores from Areas 4, 5 and 6. Results of this study are summarized in a report by Kinnetic Laboratories and Halcrow North America (2010). Summary sampling and testing data from this 2010 study are provided in Appendix A.

Areas 4, 5 and 6 sediments were deemed physically suitable for beach nourishment in 2010 while the Area 7N composite sample was not. The 2010 report described the Areas 4 and 5 composite samples as silty sand (SM). Area 4 had 87% sand and Area 5 had 86% sand. The Area 6 composite sample had 89% sand and was described as poorly grated sand (SP). The Area 7N composite sample was considerably finer with only 41% sand and it was described as sandy silt (ML).

Figure 3. Major Drainage Areas and Storm Drains into Marina del Rey Harbor.

Chemically, sediments from Composite Areas 4, 5 and 6 contained higher concentrations of some constituents than sediments collected offshore of Dockweiler State Beach. This was especially true for DDT and chlordane compounds, which exceeded NOAA lower effects, based screening levels (ERL values from Long et. al., 1995) in all three areas. Some individual cores in Area 6 contained PCB concentrations that were also elevated above reference concentrations and NOAA ERL values.

Composite Area 7N contained even more elevated constituents. NOAA upper effects based screening levels (ERM values from Long et. al., 1995) were exceeded in this composite sample for lead, DDT compounds and chlordane. PCB Aroclors and congeners as well as several metals exceeded NOAA ERL values.

A follow-up investigation to the February 2010 maintenance dredging sediment characterization study was conducted on the MDR sediments from Areas 4, 5 and 6 (Kinnetic Laboratories and Halcrow, 2011). The initial investigation was conducted for possible placement of the dredge material at Redondo and/or Dockweiler State Beaches. This follow-up investigation, which was sampled on June 8, 2011, provided Tier III and additional Tier II analyses. Tier III analyses were only conducted for possible placement at the Dockweiler State Beach Nearshore Reuse Area, not at Redondo State Beach. This follow-up investigation was conducted to address the elevated sediment concentrations and to confirm that sediments from Areas 4, 5 and 6 were not toxic to benthic organisms and that the sediments were not toxic to pelagic and demersal organisms while settling through the water column during placement offshore of Dockweiler State Beach. Results were presented in a supplemental report by Kinnetic Laboratories and Halcrow North America (2011). This report indicated that chemical concentrations in a composite sample from Areas 4 and 5 have a low potential for adverse biological effects based on comparisons to NOAA effects-based screening levels, although some contaminants in the Area 4/5 sediments were somewhat elevated over reference sediment concentrations. Despite this, the results of the solid phase toxicity testing show that mortality in the Area 4/5 sediments would not exceed the Limiting Permissible Concentration (LPC) for benthic toxicity. In addition, results of the water column bioassays show that the discharge of Area 4/5 sediments through the water column would not exceed the State’s narrative water quality standard after initial mixing. Constituent concentrations in the Area 6 sediments were not elevated over reference sediments, and there was no benthic or water column toxicity. The Corps subsequently concluded that the sediments from Areas 4, 5 and 6 were suitable for aquatic placement offshore of Dockweiler State Beach.

3.0 METHODS

This section describes the dredging design, study design, and field and analytical methods for this testing program.

3.1 Dredge Design

Bathymetric data in relationship to target sampling locations are shown on Figure 2. Figure 2 also defines the limits of dredging for Areas 4, 5, 6 and 7N. Design depths and dredge volumes for each area identified for dredging are provided in Table 1.

3.2 Study Design

The sampling and testing design for this project covers data collection tasks for Marina del Rey Harbor Entrance Channel sediment collection and testing and Dockweiler State Beach onshore and nearshore area sampling and testing. Evaluation guidelines are also discussed.

The main approach was to sample dredge sediments to dredge depths plus allowable overdepth, composite them by area, and subject the composite samples to chemical testing and, if necessary, biological testing to determine if they are suitable for beach nourishment by placing sediments directly on Dockweiler State Beach or in the nearshore area of this beach. The approach was also to determine the physical properties of the sediments at each location and at different depths.

Testing followed requirements and procedures detailed in the ITM (USEPA/USACE, 1998) with further guidance from Los Angeles District USACE guidelines (CESPL, undated) and from SC- DMMT draft guidelines. Acceptability guidelines published in these documents were used to evaluate the suitability of MDR Harbor maintenance dredging sediments for beach nourishment.

3.2.1 Marina del Rey Harbor Sediment Collection and Testing

Vibracore sampling, as described in Section 3.3.2 (Vibracore Sampling Methods), was carried out to collect subsurface sediment data at a total of 13 locations. Five (5) locations were sampled within Area 4 and five (5) locations were sampled within Area 5. The project SAP called for only three (3) locations to be sampled in Area 6. This is because a large portion of this area is located within the intertidal zone and is unsafe to access. The project sampling and Analysis Plan (SAP) also called for five locations to be sampled in Area 7N. However, Area 7N locations were not sampled since shoaling in this area was less than anticipated and the mudline elevation in most of or the entire area was below the authorized depth of -20 feet MLLW. The prefix designation for all vibracore locations was “MDRVC16-#-##.” Final sampling locations in relation to locations proposed in the project SAP are shown on Figure 2. Final coordinates, seafloor elevations, and sample collection elevations are listed in Table 5. Note that due to the lack of shoaling in the areas sampled, several locations were moved to target more shoaling. In addition, the overdepth elevation could not be reached for two locations in Area 6 because the depth of water at these locations was too shallow to accommodate a long enough core barrel for the length of cores needed.

Table 5. Actual Sampling Locations, Core Depths, Mudline Elevations, and Sampling Elevations for Marina del Rey Harbor 2016 O&M Dredging.

Comp.

Area

Core Designation Date

Sampled Time

Sampled

California Lambert Zone 5 (NAD 83)

Geographic Coordinates (NAD 83) Mudline

Elevation (ft., MLLW)

Design Depth + Overdepth (ft., MLLW)

Core Recovery

(ft.)

Core Interval Sampled

(ft., MLLW) Northing (feet)

Easting (feet)

Latitude North

Longitude West

A rea 4

E ntrance

MDRHVC16-04-1 4/12/16 13:10 1808621 6421484 33 57.678 118 27.737 -18.6 -22.0 6.9 -18.6 to -22.0

MDRHVC16-04-2 4/12/16 14:03 1808809 6421338 33 57.709 118 27.766 -17.0 -22.0 8.2 -17.0 to -22.0

MDRHVC16-04-3 4/12/16 12:25 1808930 6421500 33 57.729 118 27.734 -16.4 -22.0 9.2 -16.4 to -22.0

MDRHVC16-04-4 4/12/16 14:45 1808827 6421581 33 57.712 118 27.718 -19.8 -22.0 6.8 -19.8 to -22.0

MDRHVC16-04-5 4/12/16 13:40 1808693 6421661 33 57.690 118 27.702 -19.5 -22.0 8.2 -19.5 to -22.0

A rea 5

A pproach

MDRHVC16-05-1 4/12/16 10:55 1808998 6421293 33 57.740 118 27.775 -16.8 -22.0 9.4 -16.8 to -22.0

MDRHVC16-05-2 4/12/16 09:56 1809192 6421198 33 57.772 118 27.794 -18.9 -22.0 6.3 -18.9 to -22.0

MDRHVC16-05-3 4/12/16 11:32 1809131 6421299 33 57.762 118 27.774 -15.2 -22.0 10.0 -15.2 to -22.0

MDRHVC16-05-4 4/12/16 08:40 1809361 6421421 33 57.800 118 27.750 -16.8 -22.0 9.3 -16.8 to -22.0

MDRHVC16-05-5 4/12/16 09:15 1809368 6421143 33 57.801 118 27.805 -19.0 -22.0 6.3 -19.0 to -22.0

A rea 6

S and

T rap

MDRHVC16-06-1 4/12/16 17:10 1809615 6421574 33 57.842 118 27.720 -4.9 -30.0 10.1 -4.9 to -15.0 MDRHVC16-06-2 4/12/16 16:15 1809664 6421494 33 57.850 118 27.736 -8.6 -30.0 12.0 -8.6 to -20.6 MDRHVC16-06-3 4/12/16 18:00 1809591 6421594 33 57.838 118 27.716 -3.1 -30.0 6.0 -3.1 to -9.1

Three (3) area composite samples were created from the three (3) channel areas shown on Figure 2 and analyzed for bulk sediment chemistry. One composite sample was created from each channel area. An Area 7N composite sample was not created since the mudline elevation in this area was already below dredge depth.

Continuous samples from the mudline to project depths plus two feet for overdepth testing were collected from most core locations. These primary core intervals were homogenized and then combined with all primary core intervals in a composite area to the form composite samples for bulk sediment chemistry analyses. Additional composite material was archived in case biological testing became necessary. Sediments below overdepth elevations were often collected for USACE informational purposes only but were not included in the sediment composite samples. Table 5 summarizes composite samples formed and overdepth elevations.

In addition to the composite samples, at least one archive bulk sediment chemistry sample was collected from each core location representing the entire primary core interval (mudline to overdepth elevations). All archive samples are being stored frozen at Kinnetic Laboratories’ Santa Cruz facility for at least six months unless directed otherwise by the USACE Technical Manager.

Core subsamples for geotechnical testing were collected from the 13 primary core intervals and from any geo-physically different layer of material not already being analyzed for grain size distribution as described later in Section 3.2.3.

3.2.2 Dockweiler State Beach Reference Samples

A series of surface grabs were collected along three (3) transects perpendicular to the shore at the receiving beach and from within a nearshore area of the beach. The beach transect sampling consisted of collecting surface grab samples at eight elevations (+12, +6, 0, -6, -12, -18, -24 and - 30 feet MLLW) along the three transects perpendicular to the shore on April 13, 2016. Locations of these transects are shown on Figure 4. Sampling at the beach nearshore area identified on Figure 4 consisted of collecting sediments from eleven randomly placed sampling locations within the area. Individual geotechnical grain size testing was performed on all grab samples collected from the beach and nearshore sites. Table 6 provides a list of the final locations for the beach reference samples along with date and time of collection.

In addition to individual grain size analyses, the eleven grab samples collected from the Dockweiler State Beach nearshore area were composited into a single composite sample. This composite sample underwent bulk sediment chemical analyses along with the MDR Harbor composite samples. Data derived from the nearshore area composite sample served as reference data. Additional volume of composited sediment was archived from the Dockweiler State Beach nearshore area to serve as reference sediment for bioassay testing should this be required.

Figure 4. Location of Dockweiler State Beach Transects Sampling Locations and Location of Nearshore Placement Area Sampling Locations.

A (+12)

A (+6) A (0) A (-6)

A (-12) A (-18)

A (-24)

A (-30)

B (+12) B (+6)

B (0) B (-6)

B (-12) B (-18) B (-24)

B (-30)

C (+12)

C (+6) C (0) C (-6)

C (-12) C (-18)

C (-24)

C (-30)

D-1 D-2

D-3 D-4

D-5

D-6

D-7

D-8

D-9

D-10

D-11

Nearshore Placement Area

Table 6. Dates, Times and Sampling Coordinates for Samples Collected from Beach Reference Sites

Area Site

Designations Date Time

Sampling Elevations

(feet, MLLW)

Latitude North

Longitude West

Transect A

A+12 (A1) 4/13/2016 10:08 12 33° 56.403 118° 26.492 A+6 (A2) 4/13/2016 10:04 6 33° 56.400 118° 26.502 A0 (A3) 4/13/2016 10:00 0 33° 56.394 118° 26.515 A-6 (A4) 4/13/2016 13:03 -6 33° 56.39 118° 26.529

A-12 (A5) 4/13/2016 9:32 -12 33° 56.354 118° 26.623 A-18 (A6) 4/13/2016 12:02 -18 33° 56.349 118° 26.643 A-24 (A7) 4/13/2016 12:06 -24 33° 56.316 118° 26.737 A-30 (A8) 4/13/2016 12:11 -30 33° 56.294 118° 26.824

Transect B

B+12 (B1) 4/13/2016 10:24 12 33° 56.218 118° 26.387 B+6 (B2) 4/13/2016 10:21 6 33° 56.213 118° 26.404 B0 (B3) 4/13/2016 10:18 0 33° 56.210 118° 26.412 B-6 (B4) 4/13/2016 12:52 -6 33° 56.208 118° 26.433 B-12 (B5) 4/13/2016 9:53 -12 33° 56.163 118° 26.506 B-18 (B6) 4/13/2016 11:45 -18 33° 56.153 118° 26.553 B-24 (B7) 4/13/2016 11:51 -24 33° 56.149 118° 26.654 B-30 (B8) 4/13/2016 11:55 -30 33° 56.114 118° 26.749

Transect C

C+12 (C1) 4/13/2016 10:42 12 33° 55.997 118° 26.283 C+6 (C2) 4/13/2016 10:37 6 33° 55.992 118° 26.297 C0 (C3) 4/13/2016 10:34 0 33° 55.989 118° 26.305 C-6 (C4) 4/13/2016 12:39 -6 33° 55.98 118° 26.32 C-12 (C5) 4/13/2016 9:58 -12 33° 55.96 118° 26.397 C-18 (C6) 4/13/2016 11:27 -18 33° 55.955 118° 26.449 C-24 (C7) 4/13/2016 11:33 -24 33° 55.925 118° 26.551 C-30 (C8) 4/13/2016 11:38 -30 33° 55.895 118° 26.631

Nearshore

D-1 4/13/2016 09:50 -17 33° 56.292 118° 26.700 D-2 4/13/2016 10:21 -15 33° 56.292 118° 26.583 D-3 4/13/2016 10:31 -18 33° 56.24 118° 28.642 D-4 4/13/2016 10:34 -15 33° 56.227 118° 26.57 D-5 4/13/2016 10:44 -19 33° 56.141 118° 26.616 D-6 4/13/2016 10:43 -15 33° 56.108 118° 26.508 D-7 4/13/2016 10:50 -20 33° 56.087 118° 26.588 D-8 4/13/2016 10:57 -16 33° 56.06 118° 26.487 D-9 4/13/2016 11:00 -21 33° 56.025 118° 26.553

D-10 4/13/2016 11:08 -17 33° 56.009 118° 26.493 D-11 4/13/2016 11:15 -21 33° 55.969 118° 26.553

3.2.3 Geotechnical Samples and Testing

A sufficient quantity of sediment was collected from each location within the MDR Harbor Entrance Channel so that a representative amount of sediment is included in each geotechnical sample. At least one primary grain size sample was formed and analyzed from each core. These samples represented the material from the mudline to the project overdepth elevation. An additional thirty-two (32) sample intervals were taken within the primary core interval to characterize layers that were physically different. Grain size analyses were also run on each sampling location along the three (3) Dockweiler State Beach transects and from five of the eleven nearshore area samples for a total of 30 additional samples. Insufficient sediment was collected from six of the nearshore area samples to conduct grain size analyses. However, a composite sample of all eleven nearshore samples was submitted for analysis.

USACE, Los Angeles District requested that two (2) additional samples from each core that represents the three feet of material below the overdepth elevation be collected and tested for grain size. Data from these samples are for informational and internal purposes only, were not used for beach suitability determinations, and were not included in this report.

All mechanical grain size tests were run according to ASTM D 422 (1963). In addition to the mechanical grain size samples, three (3) hydrometer tests were run according to ASTM D 422 and four (4) Atterberg Limits tests were run according to ASTM D 4318 (2005). The hydrometer and Atterberg tests were conducted on samples with the highest proportions of fine-grained material collected from the sediment cores.

All geotechnical data gathered were used to do physical beach compatibility analyses between the dredged sediments and the receiving beach. This task was accomplished by USACE-Los Angeles District and is reported separately in Appendix B.

3.2.4 Summary of Marina del Rey Harbor Testing and Evaluation Sequence

The testing and evaluation sequence for the Marina del Rey Harbor Entrance Channel composite samples is described in detail in the next subsection and is outlined as follows:

1) Bulk sediment chemical analyses were performed on each composite sample.

2) Grain size physical compatibility analyses was conducted by the Los Angeles District U.S.

Army Corps of Engineers Geotechnical Branch.

3) Analytical results were evaluated using the sediment quality guidelines consisting of

Effects Range Low (ERL) and Effects Range Medium (ERM) values developed by Long, et al. (1995) that correlate concentrations of selected contaminants with likelihood of adverse biological effects. The sediment chemistry summary tables in Section 4 (Results) lists available ERL and ERM values. Please note that ERLs and ERMs have not been developed for all analytes.

4) Analytical results were also evaluated using the USEPA’s RSL (Regional Screening Levels) (USEPA Region 9, updated 2015) and the State of California’s CHHSL (California Human Health Screening Levels) for potential effects to humans (Cal/EPA, 2005 – updated 2010). The sediment summary table in Section 4 (Results) lists the available RSL and CHHSL values.

If grain size characteristics are compatible with the receiving beaches and contaminant levels are low compared to lower effects based screening levels and human health screening levels, then the sediments should be suitable for beach nourishment and no further testing is required. If elevated concentrations of contaminants exist, then further testing may be required by the Southern California Dredged Material Management Team.

3.2.5 Evaluation Guidelines

As mentioned above, to aid in the evaluation of sediment test data, chemical concentrations of contaminants found within the sediments were compared to sediment quality guidelines (Long et.

al., 1995) developed by NOAA. These guidelines can be used to screen sediments for contaminant concentrations that might cause biological effects and to identify sediments for further toxicity testing. For any given contaminant, ERL guidelines represent the 10th percentile concentration value in the NOAA database that might be expected to cause adverse biological effects and ERM guidelines reflect the 50th percentile value in the database. Note that ERLs and ERMs will only be used as a screening tool. They will not be used to determine suitability. The suitability determination will be made by the USACE in consultation with the SC-DMMT based on the results reported in this SAPR.

As an additional measure of potential toxicity, the mean ERM quotient (ERMq) for the composite sample can be calculated according to Long et al. (1998a) and Hyland et al. (1999). ERMq is calculated by dividing each contaminant concentration by its respective ERM value and then summing the results and dividing through by the number of contaminants as shown in the following equation:

ERM

entrationSampleConctERMQuotien 24

In cases where concentrations of measured contaminants are below the method detection limit (MDL), a value of ½ the MDL was used for the ERMq calculations. For a general overall indication of toxicity, a quotient less than 0.1 is indicative of a low probability (<12%) of a highly toxic response to marine amphipods (Long and MacDonald, 1998b). If there are no ERL exceedances in a sample, there is less than a 10% probability of a highly toxic response to marine amphipods. The probability of a highly toxic response increases to 71% for quotients greater than 1.0.

The dredge material was also assessed to whether or not it is suitable for human contact. To do so, the chemical results were compared to “Regional Screening Levels for Chemical Contaminants at Superfund Sites" (USEPA Region 9, updated 2015), formerly known as Preliminary Remediation Goals (PRGs). These screening levels (RSLs) were developed for Superfund/RCRA programs and are a consortium of USEPA Region 9 Preliminary Remediation Goals (PRGs), USEPA Region 3 Risked-Based Concentrations (RBCs) and EPA Region 6 Human Health Medium – Specific Screening Levels (HHMSSLs). RSLs are risk-based concentrations derived from standardized equations combining exposure information assumptions with EPA toxicity data.

RSLs used for this report are based on a target hazard quotient of 1.

RSLs are considered by the USEPA to be protective for humans (including sensitive groups) over a lifetime. However, RSLs are not always applicable to a particular site and do not address non-human health endpoints, such as ecological impacts. The RSLs in the sediment chemistry summary table were calculated without site-specific information. They are used for site "screening." RSLs are not cleanup standards and were not applied as such. The RSL's primary role in site "screening" is to help identify areas, constituents, and conditions that require further federal attention at a particular site, and is also useful in determining risks to human exposure at non-superfund sites. RSLs may be lower than the California Title 22 Total Threshold Limit Concentration (TTLC) values, but often are much higher.

Human health risks to the sediments were also evaluated using California Human Health screening Levels (CHHSLs). CHHSLs (Cal/EPA, updated 2010) are concentrations of 54 hazardous chemicals in soil or soil gas that are considered protective of human health. The CHHSLs were developed by the Office of Environmental Health Hazard Assessment (OEHHA) on behalf of California Environmental Protection Agency (Cal/EPA). CHHSLs were developed using standard exposure assumptions and chemical toxicity values published by the USEPA and Cal/EPA.

CHHSLs listed in the sediment chemistry summary table (Section 4) were developed separately for industrial/commercial settings and for residential settings.

3.3 Field Sampling Protocols

Vibracore sampling, grab sampling, decontamination, sample processing and documentation procedures are discussed in this section.

3.3.1 Positioning and Depth Measurements

Positioning at sampling locations was accomplished using a differential GPS (DGPS) navigation system referenced to a local geodetic benchmark with positioning accuracies of 3 to 10 feet. The locations were recorded in both Geographic coordinates (NAD 83) and State Plane Coordinates (CA Zone VI, NAD 83). Water depths were measured with a graduated lead line and corrected to mean lower low water (MLLW). Tidal stage was determined using NOAA predicted tide tables checked against a local tide gage or real-time tidal stage data. These tide data were used to calculate the seafloor elevation/mudline for each site.

All sampling sites were located within the Federal Channel limits and were close to target coordinates. Several sites were moved slightly to find adequate shoaling and for safety reasons.

3.3.2 Vibracore Sampling Methods

All MDR Harbor sediment samples were collected using an electric vibracore. The cores were advanced beyond the target sampling elevation (project elevations plus two feet for overdepth allowance plus three feet for geotechnical purposes only) or to the depth of refusal or to the maximum depth could be done from the vessel used. At the conclusion of a successful vibracore, the core liner was removed and split open for inspection and sampling. Extrusion of the cores was not allowed. Processing took place on a floating pontoon vessel.

Vibracore sampling was conducted from the 35-foot vessel DW Hood. This vessel was fully equipped with all necessary navigation, safety, and lifesaving devices per Coast Guard requirements and is capable of three-point anchoring. A 17-foot Boston whaler was used to assist in anchoring.

Kinnetic Laboratories’ vibracore consists of a 4-inch diameter aluminum coring tube, a stainless steel cutting tip, and a stainless-steel core catcher. Inserted into the core tubes were food-grade clean polyethylene liners. 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 with a boom. The unit was then vibrated until it reached below the target sampling elevation or until the depth of refusal was reached.

When penetration of the vibracore is complete, power was shut off to the vibra-head, and the vibracore was brought aboard the vessel. A check valve located on top of the core tube reduces or prevents sediment loss during pullout. The core tube was then detached from the vibra-head, and the core-cutting tip and catcher were removed. Afterwards, the core liners were removed and sealed on both ends and transported to the floating pontoon vessel for processing.

A stand was used to support the vibracore in waters unprotected from wave action. The vibracore and stand is lowered overboard from the sampling vessel as one unit. Use of a stand allows the sampling vessel to move off the sampling location while the coring apparatus penetrates the sediment. Thus, one-point anchoring or no anchoring can be utilized. A stand also prevents the coring apparatus from being pulled up from waves while trying to penetrate, thus alleviating multiple penetrations of the same material.

3.3.3 Vibracore 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 consisted 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.

3.3.4 Core Processing

Whole cores were processed on the deck of a pontoon support vessel. The deck had a plastic covering that was freshly changed for every core. Cores were placed in 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 in 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) and D-2487 (2006). Additional sediment characteristics including likely sediment origin and other observations were also recorded. A geologist from Diaz Yourman and Associates did the lithologic logging along with collection of sample splits for geotechnical testing.

Photographs were taken of each core (each photograph covered a maximum two-foot interval).

These pictures are included as Appendix C of this report.

Following logging, vertical composite subsamples were then formed from each core and samples for grain size analyses were formed. The primary vertical composite subsamples were from the mudline to two feet below the project depth or depth of refusal. Primary vertical composite subsamples were used to form area composite samples for chemical testing. An archived sample was formed from each primary vertical composite subsample. Since there were no distinct geologic stratification greater than two (2) feet nor any layers of suspected contamination in the cores, no additional archive samples were collected. Distinct geologic strata greater than eight inches in length were analyzed or archived for grain size.

Vertical composite subsamples were formed by combining and homogenizing a representative sample from each primary core interval, as described in Section 3.3.2, in a…