Att 13- Revised SAP 5-27-20_0001.pdf

Santa Monica Mountains National Recreation Area May 27, 2020 Page | i

Woolsey Fire Cleanup Sampling and Analysis Plan

Santa Monica Mountains National Recreation Area Paramount Ranch, Peter Strauss Ranch, Morrison Ranch, Rocky Oaks, Cooper

Brown, Dragon Property, Miller Property, Arroyo Sequit, Circle X Ranch

Prepared by

Terraphase Engineering, Inc.

5/27/2020

May 27, 2020 Page | ii

Signatories:

[Federal Government Lead]

[Signature]

[Date Signed]

[Cleanup Lead]

[Legal Lead]

[Regional Coordinator]

[Contaminated Sites Program]

By signing above, the signatories verify that they understand and concur with the information, procedures, and recommendations presented herein.

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Table of Contents

List of Figures ........................................................................................................................................ v

List of Tables .......................................................................................................................................... v

1 Introduction .................................................................................................................................. 1-1

1.1 CERCLA and National Park Service (NPS) Authority ................................................... 1-1

1.2 Purpose of Field Sampling...................................................................................................... 1-2

2 Site Description and Conceptual Site Model ...................................................................... 2-4

2.1 Site Description .......................................................................................................................... 2-4

2.1.1 Project Areas .................................................................................................................................. 2-4

2.1.2 Waste Characteristics ................................................................................................................ 2-6

2.1.3 Site Geology .................................................................................................................................... 2-7

2.1.4 Site Hydrology ............................................................................................................................... 2-7

2.1.5 Local Climate ................................................................................................................................. 2-7

2.1.6 Ecological Setting and Sensitive Environments ............................................................. 2-8

2.1.7 Current and Future Property Use Scenarios .................................................................... 2-2

2.1.8 Summary of Previous Investigations ................................................................................... 2-2

2.1.9 Contaminants of Potential Concern ..................................................................................... 2-2

2.1.10 Media of Potential Concern ..................................................................................................... 2-2

2.2 Scenarios for Potential Human and Ecological Exposure .......................................... 2-2

2.2.1 Human Receptors and Exposure Pathways ...................................................................... 2-2

2.2.2 Ecological Receptors and Exposure Pathways ................................................................ 2-3

2.2.3 Key CSM Assumptions ................................................................................................................ 2-3

3 DQO Planning Team and Stakeholders ................................................................................ 3-1

3.1 DQO Planning Team .................................................................................................................. 3-1

3.2 Decision-Makers ........................................................................................................................ 3-1

3.3 Stakeholders ................................................................................................................................ 3-1

4 Data Quality Objectives ............................................................................................................. 4-2

4.1 State the Problem(s) ................................................................................................................. 4-2

4.2 Identify the Goal(s) of the Investigation ........................................................................... 4-2

4.3 Identify Information Inputs ................................................................................................... 4-3

4.3.1 Previous Data Usability ............................................................................................................. 4-3

4.3.2 Data to be Collected in the Current Investigation ......................................................... 4-3

4.4 Define the Boundaries of the Investigation ..................................................................... 4-4

4.4.1 Spatial Boundaries ...................................................................................................................... 4-4

4.4.2 Temporal Boundaries ................................................................................................................ 4-4

4.4.3 Sampling Areas ............................................................................................................................. 4-5

4.5 Develop the Analytic Approach ............................................................................................ 4-5

4.5.1 Decision or Estimation Parameters ..................................................................................... 4-5

4.5.2 Action Levels .................................................................................................................................. 4-5

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4.6 Performance or Acceptance Criteria .................................................................................. 4-6

4.6.1 Quality Assurance/Quality Control ...................................................................................... 4-6

4.6.2 Decision Error Limits and Uncertainty Evaluation.................................................... 4-12

4.6.3 Data Validation and Usability ............................................................................................. 4-12

4.7 Plan for Obtaining the Data ................................................................................................. 4-13

5 Field Sampling Plan .................................................................................................................... 5-1

5.1 Ash Sampling ............................................................................................................................... 5-1

5.1.1 Ash Sampling Locations ............................................................................................................ 5-1

5.1.2 Ash Sampling Protocol .............................................................................................................. 5-1

5.1.3 Ash Sampling Health and Safety ........................................................................................... 5-1

5.1.4 Ash Field Measurements ........................................................................................................... 5-1

5.1.5 Ash Analytical Measurements/Methods ............................................................................ 5-2

5.2 Background Soil Sampling ..................................................................................................... 5-2

5.2.1 Background Soil Sampling Locations ................................................................................. 5-2

5.2.2 Background Soil Sampling Protocol .................................................................................... 5-2

5.2.3 Background Soil Sampling Health and Safety ................................................................ 5-2

5.2.4 Background Soil Field Measurements ................................................................................ 5-2

5.2.5 Ash Analytical Measurements/Methods ............................................................................ 5-3

5.3 Post-Removal Soil Sampling .................................................................................................. 5-3

5.3.1 Post-Removal Soil Sampling Locations .............................................................................. 5-3

5.3.2 Post-Removal Soil Sampling Protocol ................................................................................. 5-3

5.3.3 Post-Removal Soil Sampling Health and Safety ............................................................. 5-3

5.3.4 Post-Removal Soil Field Measurements ............................................................................. 5-3

5.3.5 Post-Removal Soil Analytical Measurements/Methods .............................................. 5-3

5.4 Sample Handling ........................................................................................................................ 5-4

5.4.1 Sample Designation .................................................................................................................... 5-4

5.4.2 Sample Labeling ........................................................................................................................... 5-4

5.4.3 Sample Handling and Chain of Custody ............................................................................. 5-4

5.4.4 Documentation and Records................................................................................................... 5-4

5.5 Investigative-Derived Waste Handling ............................................................................. 5-5

5.6 Health and Safety ....................................................................................................................... 5-5

6 Data Management ....................................................................................................................... 6-1

7 Assessment and Oversight ....................................................................................................... 7-1

7.1 Assessment and Corrective Actions ................................................................................... 7-1

7.1.1 Field Audit and Response Actions ......................................................................................... 7-1

7.1.2 Laboratory Audit and Response Actions ............................................................................ 7-1

7.2 Quality Assessment Reporting ............................................................................................. 7-2

7.2.1 Data Verification and Validation .......................................................................................... 7-2

7.3 Data Usability .............................................................................................................................. 7-2

8 Investigation Outputs ................................................................................................................ 8-1

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9 References ..................................................................................................................................... 9-2

List of Abbreviations and Acronyms ........................................................................................... vi

Appendix A – Laboratory Standard Operating Procedures

Appendix B – Health and Safety Plan (HASP)

List of Figures Figure 1 – Site Location Map Figure 2 – Paramount Ranch Location Map Figure 3 – Peter Strauss Ranch Location Map Figure 4 – Rocky Oaks/Cooper Brown Location Map Figure 5 – Arroyo Sequit Location Map Figure 6 – Circle X Ranch Location Map Figure 7 – Morrison Ranch Location Map Figure 8 – Miller Property Loction Map Figure 9 – Dragon Property Location Map Figure 10 – Preliminary Scenarios for Potential Human Exposure Figure 11 – Preliminary Scenarios for Potential Ecological Exposure

List of Tables Table 1 – Site Area Locations, Structure Descriptions and Sample Analyses Table 2 – Ecological Plant Species Table 3 – Ecological Terrestrial Species Table 4 – Prelimimary Scenarios for Potential Human Exposure Table 5 – Hazardous Waste Characterization Criteria Table 6 – Chemicals, Reference Limits, and Laboratory Accuracy and Precision Objectives Table 7 – Data Quality Indicators

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List of Abbreviations and Acronyms BGS Below ground surface

BSA Boy Scouts of America

BTV Background Threshold Value

CERCLA Comprehensive Environmental Response, Compensation, and Liability Act

COC Chain of Custody

COPC Contaminant of Potential Concern

CrVI Chromium (VI)

CSM Site Conceptual Site Model

DQO Data Quality Objective

EDD Electronic Data Deliverable

EPC Exposure Point Concentration

FSP Field Sampling Plan

GPS Global Positioning System

HASP Health and Safety Plan

IDQTF Intergovernmental Data Quality Task Force

MDL Method Detection Limit

NPS National Park Service

NCP National Oil and Hazardous Substances Pollution Contingency Plan

PCB Polychlorinated Biphenyl

QAPP Quality Assurance Project Plan

QA/QC Quality Assurance/Quality Control

SAP Sampling and Analysis Plan

SAMO Santa Monica Mountains National Recreation Area

SOP Standard Operating Procedure

STLC Soluble Threshold Level Concentration

TCLP Toxicity Characteristic Leachate Procedure

TCRA Time Critical Removal Action

TTLC Total Threshold Limit Concentrations

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UCLA University of California at Los Angeles

USEPA United States Environmental Protection Agency

UTL Upper Tolerance Limit

WET Waste Extraction Test

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1 Introduction This document serves as the Sampling and Analysis Plan (SAP) for the Woolsey Fire Time Critical Removal Action project in the Santa Monica Mountains National Recreation Area (SAMO) (the Site, Figure 1). A total of 31 structures were destroyed during the Woolsey Fire in November 2018 (Table 1).

The structures were located in the nine project areas of the Site (i.e., Paramount Ranch, Peter Strauss Ranch, Rocky Oaks, Cooper/Brown, Arroyo Sequit, Circle X Ranch, Morrison Ranch, Miller Property, and the Dragon Property).

The purpose of this SAP is to:

• Detail the sampling and analytical methods that will be used to characterize the nature and extent of site-related chemicals of potential concern (COPC) in ash prior to performing response activities;

• Detail the sampling and analytical methods that will be used to characterize naturally occurring metals concentrations in soil in the vicinity of each of the nine project areas;

• Document the human health and ecological screening levels used to inform the laboratory reporting requirements to achieve the necessary data quality objectives (DQOs);

• Detail the sampling and analytical methods that will be used to characterize the nature and extent of site-related COPC in surface soil following the performance of response activities; and

• Establish the general data evaluation approach(es) that will be used to support Removal Action decision-making.

1.1 CERCLA and National Park Service (NPS) Authority

This SAP was generated in general accordance with the United States Environmental Protection Agency’s (USEPA) Guidance on Systematic Planning Using the Data Quality Objectives Process (USEPA 2006), Guidance for Quality Assurance Project Plans (USEPA 2002), EPA Requirements for Quality Assurance Project Plans (USEPA 2001), and the Intergovernmental Data Quality Task Force’s (IDQTF) Uniform Federal Policy for Quality Assurance Project Plans (IDQTF 2005). The National Park Service (NPS) is authorized under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), 42 USC. Section 9601 et seq., to respond as the Lead Agency to a release or threatened release of hazardous substances and/or a release or threatened release of any pollutant or contaminant that may present an imminent and substantial danger to public health or welfare on NPS land.

CERCLA’s implementing regulations, codified in the National Oil and Hazardous Substances Pollution Contingency Plan (NCP), 40 CFR Part 300, establishes the framework for responding to such releases and threatened releases. The NCP prescribes two similar processes for responding to releases: removal actions and remedial actions (see NCP Sections 300.400 through 300.440). In accordance with the NCP (40 CFR Part 300, Subpart §300.415), the following factors are used in considering the appropriateness of a removal action:

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1. Actual or potential exposure to nearby human populations, animals, or the food chain from hazardous substances, pollutants, or contaminants

2. Actual or potential contamination of drinking water supplies or sensitive ecosystems

3. Hazardous substances, pollutants, or contaminants in drums, barrels, tanks, or other bulk storage containers, that may pose a threat of release

4. High levels of hazardous substances, pollutants, or contaminants in soil largely or near the surface that may migrate

5. Weather conditions that may cause hazardous substances, pollutants, or contaminants to migrate or be released

6. Threat of fire or explosion

7. The availably of other appropriate federal or state response mechanisms to respond to the release

8. Other situations or factors that may pose threats to public health or welfare of the United

States or the environment.

If environmental samples are to be collected under either process, a SAP is required (see NCP Sections

300.415 and 300.430).

The SAP includes the Field Sampling Plan (FSP) which describes the number, types, and locations of samples and the types of analyses that will be conducted on the samples. The SAP also describes the project’s policy framework, organization, functional activities, data quality objectives (DQOs), and measures necessary to achieve the goals of the study.

In addition, the NPS has many regulations that apply to the release of hazardous substances on NPS land (see NPS 2015) including the NPS Organic Act of 1916 (16 USC Section 1, et seq., 36 CFR Part 1), which requires that the NPS manage parks in order to conserve the scenery, natural and historic objects, and wildlife and to provide for their enjoyment by such means as will leave them unimpaired for the enjoyment of future generations. Therefore, whether conditions at the Site pose unacceptable risks to the interaction of organisms and the environment is especially relevant to the NPS responsibility to protect park resources.

To the extent practicable, all work will be conducted in accordance with USEPA guidance, Green Remediation: Incorporating Sustainable Environmental Practices into Remediation of Contaminated Sites (USEPA 2008).

1.2 Purpose of Field Sampling

The purpose of the field sampling effort will be to adequately characterize the nature and extent of COPCs in ash at the nine impacted areas for waste disposal purposes and develop removal goals that can support the evaluation of post-cleanup soil sampling results to confirm completion of Removal Action.

This will involve:

1. Characterizing the nature and extent of COPCs in ash, generated when structures in the nine areas were destroyed by fire to facilitate disposal of the ash material during response activities;

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2. Characterizing the range of naturally occurring metals concentrations in soil in the vicinity of each of the nine project areas to support the development of removal goals; and

3. Characterizing the nature and extent of COPCs in surface soil, following the implementation of response activities, in order to confirm that conditions following cleanup are equal to or below the removal goals.

The sampling events will be conducted in 2019 and 2020. Data generated from these sampling events will be used in accordance with the provisions outlined in the DQOs detailed in Section 4.

The sampling that will be performed is summarized on Table 1 and is as follows:

• Up to 16 ash samples (total) in the vicinity of 28 burned and destroyed structures, located within eight of the nine project areas1, will be collected and analyzed for Title 22 metals via USEPA Method 6010B/7471A, including one sample at each area (8 samples) that will be analyzed for chromium (VI) (CrVI) via USEPA Method 7196A, dioxins and furans via USEPA Method 8920, PCBs via USEPA Method 8082 and asbestos via USEPA Method 600;

• A total of 90 background soil samples from six selected areas (15 samples collected from each selected area, Figures 2, 3, 4, 5, 7 and 9), will be collected and analyzed for Title 22 metals via USEPA Method 6010B/7471A, including 20% of samples (3 samples per area) that will be analyzed for CrVI via USEPA Method 7196A; and,

• A total of 120 post-Removal Action soil samples in the vicinity of 28 burned and destroyed structures, located within nine project areas, will be collected and analyzed for Title 22 metals via USEPA Method 6010B/7471A, including 20% of samples per area that will be analyzed for CrVI via USEPA Method 7196A, and dioxins and furans via USEPA Method 8920.

• Locations of previous structures where limited or non-existent ash was observed will not be sampled for ash or soil.

1 Ash is not present at Circle X Ranch and this area is not included for sampling.

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2 Site Description and Conceptual Site Model

2.1 Site Description

The Site is located in the SAMO in Los Angeles and Ventura Counties, California and consists of 182,440 acres of land. The NPS controls 23,620 acres of the SAMO and the California State Park system controls 42,000 acres. The rest of the SAMO is controlled by local agency parks, university study reserves, and private property conservation easements.

2.1.1 Project Areas

In November of 2018, the Woolsey Fire destroyed 21,000 acres (88%) of NPS land within the Site, including 269 known archaeological sites, two cultural landscapes and 32 historical buildings. The nine project areas where structures were destroyed in the Fire and which are the subject of this sampling scope are shown on Figure 1. The locations of each of the nine project areas subject to this sampling scope are as follows:

1. Paramount Ranch (see Figure 2)

- 2903 Cornell Rd

Agoura Hills, CA 91301

- 34.115508°, -118.756145°

2. Peter Strauss Ranch (see Figure 3)

- 30000 Mulholland Hwy Agoura Hills, CA 91301

- 34.113496°, -118.779316°

3. Rocky Oaks (see Figure 4)

- 107 Kanan Dume Rd Malibu, CA 90265

- 34.098123°, -118.813196°

4. Cooper/Brown (see Figure 4)

- 31915 Mulholland Hwy Malibu, CA 90265

- 34.097067°, -118.815981°

5. Arroyo Sequit (see Figure 5)

- 34138 Mulholland Hwy Malibu, CA 90265

- 34.086259°, -118.890645°

6. Circle X Ranch (see Figure 6)

- 12896 Yerba Buena Rd

Malibu, CA 90265

- 34.109734°, -118.937229°

7. Morrison Ranch (see Figure 7)

- Near Cheeseboro Canyon Rd at Cheeseboro Rd Agoura Hills, CA 91301

- 34.154874°, -118.727014°

8. Miller Property (see Figure 8)

- 2200 Latigo Canyon Rd Malibu, CA 90265

- 34.074250°, -118.784160°

9. Dragon Property (see Figure 9)

- Near Trancas Canyon Rd at Edison Rd

Malibu, CA 90265

- 34.050842°, -118.852780°

The following sections provide additional details for each area.

Paramount Ranch

Paramount Ranch is a 2,700-acre ranch located in Agoura Hills, California (34.115508°, -118.756145°).

Paramount Ranch and features burned in the Woolsey Fire are shown on Figure 2. The land was

May 27, 2020 Page | 2-5 purchased by Paramount Studios in 1927 and, prior to the Fire, was used as a movie set where numerous television shows and movies had been filmed. Paramount Ranch was open to the public for tours of the property and private events and contains hiking trails. A total of ten structures were burned in the Fire including the freight building, private quarters 107, the mercantile building, the pavilion, the saloon, the horse barn, the jail, the restroom, the hotel, and the telegraph office (Figure 2). In 1956, the owner of Paramount Ranch built a road-racing track adjacent to Medea Creek. The track was 2 miles in length and featured 11 turns and a bridge and underpass in the northern section of the course. The racetrack bridge was the eleventh feature burned in the Fire. Details about structures destroyed are presented in Table 1.

Peter Strauss Ranch

Peter Strauss Ranch is a located in Agoura Hills, California (34.113496°, -118.779316°). Peter Strauss Ranch and the features burned in the Fire are shown on Figure 3. Peter Strauss Ranch was first owned by automobile manufacturer Henry Miller and used as a weekend retreat. In 1926, Miller built the stone ranch rouse, look-out tower, and aviary. The property was sold in the mid-1930s to developers Warren Shobert and Arthur Edison who turned the property into a recreational amusement park called Lake Enchanto. The property was sold to actor Peter Strauss in 1976, who turned the property into a private estate. The land was sold to the Santa Monica Mountains Conservancy in 1983 and later to the NPS in 1987. The ranch contains hiking trails, a swimming pool in the Lake Enchanto dam, and previously allowed access to the stone ranch house. The ranch house was burned in the Fire. Details about structures destroyed are presented in Table 1.

Rocky Oaks

Rocky Oaks is located in Malibu, California (34.098123°, -118.813196°). Rocky Oaks and the features burned in the Fire are shown on Figure 4. This area was originally part of the Rocky Oaks Ranch, established in the 1920s by Albert and Anna Bradenberger. The area is maintained by the NPS and contains hiking trails and a seasonal man-made pond. Features destroyed in the Fire include the Quarters 102 House, the Museum Building, a vault restroom and a chicken coup. Details about structures destroyed are presented in Table 1.

Cooper/Brown

Cooper/Brown is located directly adjacent to and west of the Rocky Oaks park unit in Malibu, California (34.097067°, -118.815981°). The Cooper/Brown area and features burned in the Fire are shown on Figure

4. The area contained the Bradenberger-Brown house, or the Cooper/Brown house, constructed by Albert and Anna Bradenberger in the 1940s. Details about structures destroyed are presented in Table 1.

Arroyo Sequit

Arroyo Sequit is located in Malibu, California (34.086259°, -118.890645°). the Arroyo Sequit area and features burned in the Fire are shown on Figure 5. It was purchased by Richard Mason and Mabel Kelch in the 1920s and sold to the State of California in 1985, following a large wildfire in the area. The NPS acquired the land in 1991. Arroyo Sequit contained a picnic area for visitor use and a wood frame ranch house used as a ranger residence. Features destroyed in the Woolsey Fire include the Quarters 113 house, May 27, 2020 Page | 2-6 the survey office, the vault restroom and the pump house. Details about the structures destroyed are presented in Table 1.

Circle X Ranch

Circle X Ranch is located in Malibu, California (34.109734°, -118.937229°). Circle X Ranch and the features burned in the Woolsey Fire are shown on Figure 6. The site was a former Boy Scout Camp created by the Exchange Club of Los Angeles and the Boney Ridge Country Club in 1949. In 1951, the Boy Scouts of America (BSA) signed a 99-year lease with the Circle X Ranch foundation, and in 1979, the foundation deeded the land to the BSA. In 1987, the NPS bought the land from the BSA and the NPS has managed an on-site campground since 1989 as well as several hiking trails open to the public.

Features destroyed in the Woolsey Fire include the basketball court and vault toilets A and B. Details about the structures destroyed are presented in Table 1.

Morrison Ranch

Morrison Ranch is located in Agoura Hills, California (34.154874°, -118.727014°). Morrison Ranch and the features burned in the Woolsey Fire is shown on Figure 7. The property was purchased by John W.

Morrison in 1904 and was used as a cattle ranch. Morrison Ranch was acquired by the NPS in 1999.

Features destroyed in the Woolsey Fire include the Morrison Ranch house, the chicken coup and the corral area. Details about structures destroyed are presented in Table 1.

Miller Property

The Miller Property is located in Malibu, California (34.074250°, -118.784160°). The Miller Property and features burned in the Woolsey Fire are shown on Figure 8. The property is a recent purchase of the NPS. The Miller Property, formerly a roofed area which covered recreational vehicles, was burned in the Woolsey Fire. Details about structures destroyed are presented in Table 1.

Dragon Property

The Dragon Property is a park unit located in Malibu, California (34.050842°, -118.852780°). The Dragon Property and features burned in the Woolsey Fire are shown on Figure 9. The property is a recent purchase of the NPS. The structures destroyed during the Woolsey Fire include an Air Stream trailer, a school bus called the Life Estate, and a pump house. Details about structures destroyed are presented in Table 1.

2.1.2 Waste Characteristics

The nine project areas did not represent areas which stored or generated hazardous waste prior to the fire, other than household hazardous waste. The descriptions of the former structures at each of the nine areas are presented in Table 1. Many of the structures destroyed in the Woolsey Fire were constructed of either wood or metal frames, some including metal siding, asphalt shingles and other building materials. Older structures may have been constructed using asbestos-containing materials. As a result, the potential presence of COPCs in ash/surface soil at the nine areas are attributable to burning of these building materials or to the building materials themselves.

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2.1.3 Site Geology

The SAMO forms the western portion of the east-west trending Transverse Ranges of Southern California. The Transverse Ranges were rotated clockwise approximately 90°–110° and uplifted in the last 20 million years coinciding with the development of the San Andreas Fault. Sedimentary rocks include lithologies deposited in marine settings over 21 million years ago that were uplifted in an active tectonic setting. Igneous rocks include intrusive granitic varieties emplaced during the Cretaceous period as well as extrusive varieties which developed in marine environments and were subsequently uplifted.

The most common metamorphic rocks in the area are slate from the Jurassic to early Cretaceous period that were metamorphosed while being sutured to the North American continental margin. The SAMO has been a tectonically active area throughout the Quaternary period where uplift and extensive folding and faulting has produced widespread occurrences of landslides (NPS 2016). In addition, many low-lying areas have accumulated alluvial deposits over time due to numerous ephemeral streams in the area.

2.1.4 Site Hydrology

The nine project areas are located in two major watersheds within the SAMO: the Malibu Creek Watershed and the Coastal Watersheds. The Malibu Creek Watershed drains to the Pacific Ocean via Malibu Creek. The Coastal Watersheds are a series of steep drainages on the southern section of the Site that drain to the Pacific Ocean. The rainy season ranges from approximately December to April and the dry season for the remainder of the year. Average yearly rainfall ranges from 12.5 to 15 inches along the coast and up to 24 inches inland, at higher elevations. Malibu, Solstice and Topanga Creeks are perennial streams that flow in the SAMO, and countless others are ephemeral streams that coincide with the rainy season. Several areas of the Site are located adjacent to aquatic features. The Peter Strauss Ranch area is located adjacent to an ephemeral drainage, formerly dammed to create Lake Enchanto. This drainage flows to Lake Malibu. Paramount Ranch is located adjacent to Madea Creek, which is upstream from Lake Malibu.

2.1.5 Local Climate

The SAMO has a Mediterranean-type climate. This climate type is characterized by cool, wet winters and hot, dry summers. Coastal area temperatures are moderated in the summer by fog which occurs along the coast in the southern part of the SAMO. December through March are the coolest months and July through October are the hottest months in the SAMO. The average mean temperature in January ranges from 50-65 degrees F; summers are a little warmer with an average mean temperature in July that ranges from 65-76 degrees F. Both winter and summer temperature extremes are moderated by the moist ocean air with generally high nighttime humidity and frequent fog. Diurnal temperature differences are small with cool days and warm nights. Strong winds blowing from the east, known as Santa Ana winds, occur in the later summer and fall months and increase the chances for forest fires.

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2.1.6 Ecological Setting and Sensitive Environments

The Santa Monica Mountains are part of the east-west trending Transverse Ranges of Southern California. The range is characterized by steep, rugged mountain slopes and canyons with elevations ranging from sea level to more than 3,000 feet. The Santa Monica Mountains are adjacent to 46 miles of California coastline with sandy beaches and rocky tide pools and lagoons.

The mountains are home to over 1,000 plant species making up 26 distinct natural communities, from freshwater aquatic habitats and two of the last salt marshes on the Pacific Coast, to oak woodlands, valley oak savannas, coastal sage, and chaparral. Over 45 mammal species are found in the Santa Monica Mountains, including bobcats, coyotes, and mountain lions. Nearly 400 species of birds have been observed and another 35 species of reptiles and amphibians can also be found in the mountains. The rare, threatened and endangered plant and animal species (NPS 2005) are listed below:

Plants:

• Braunton’s milk-vetch

• Coastal dunes milk-vetch

• Salt march birds-beak

• Conejo dudleya

• Agoura Hills dudleya

• Blochman’s dudleya

• Many-stemmed dudleya

• Marcescent dudleya

• Santa Monica

Mountains dudleya

• Verity’s dudleya

• Lyon’s Pentachaeta

• Conejo buckwheat

• Santa Susana tarplant

• Plummer’s mariposa lily

• Dune larkspur

• Coulter’s goldfields

• Parry’s Spineflower

• California beargrass

• Mud nama

• Rayless ragwort

• Sonoran maiden fern

• Lewis’s evening-primrose

• Vernal barley

• Red sand-verbena

• Plummer’s baccharis

• Round-leaved boykinia

• Seaside calandrinia

• Island mountain-mahogany

• Southern mountain misery

• Western dichondra

• Suffretescent wallflower

• Santa Barbara bedstraw

• Southwestern spiny rush

• Fragrant pitcher sage

• Fish’s milkwort

• Estuary seablite

• Malibu baccharis

Birds:

• Swainson’s Hawk

• Peregrine Falcon

• Marbled Murrelet

• Bank Swallow

• Least Bell’s Vireo

• Belding’s Savannah Sparrow

• American White Pelican Birds

• Harlequin Duck

• Cooper’s Hawk

• Northern Harrier

• Osprey

• Merlin

• Prairie Falcon

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• Mountain Quail

• Long-billed Curlew

• Elegant Tern

• Long-eared Owl

• Burrowing Owl

• California Horned

Lark

• San Diego (Coastal)

Cactus Wren

• Loggerhead Shrike

• Tri-colored Blackbird

• Southern California Rufous-crowned Sparrow

• Yellow Warbler

• Western Snowy

Plover

• Southwestern Willow

Flycatcher

• California Condor

• Bald Eagle

• Brown Pelican

• California

Gnatcatcher

• Light-footed Clapper

Rail

• California Least Tern

• Least Bell’s Vireo

Mammals:

• Spotted Bat

• Greater Western

Mastiff Bat

• California Leaf-nosed Bat

• Occult Little Brown Bat

• Pacific Western Big-eared Bat

• Salt Marsh Ornate Shrew

• American Badger

Reptiles:

• Southwestern Pond Turtle

• San Diego Horned Lizard

• California Horned Lizard

• Coastal Western Whiptail

• Silvery Legless Lizard

• San Bernardino Ringneck Snake

• San Diego Mountain King Snake

• Coastal Rosy Boa

• Coast Patch-nosed

Snake

• Two-striped Garter

Snake

Amphibians:

• California Red-legged Frog • Coast Range Newt

Fishes:

• Tidewater Goby • Southern California Steelhead Trout

Invertebrates:

• Wright’s Checkerspot Butterfly

• Callippe Silverspot Butterfly

• Clouded Tailed Copper Butterfly

• Salt Marsh Skipper

• Santa Monica Mountains Hairstreak

• Belkins Dune Tabanid Fly

• Santa Monica Shieldback Katydid

• Valley Oak Ant

Potential ecological receptor groups include terrestrial birds, mammals, reptiles, amphibians, and vegetation. These species are summarized in Tables 2 and 3.

2.1.7 Current and Future Property Use Scenarios

The nine areas impacted by the Fire have been predominantly used for recreational purposes. Currently, as a result of the Fire, access to these areas is limited. In the future, following restoration, use of these areas may involve recreational activities, routine work and maintenance activities by NPS staff, or use of these lands as residences for NPS staff. Adjacent to, or in close proximity to, these nine impacted areas are land that is (or could be) used for similar purposes (i.e., recreational and residential use).

2.1.8 Summary of Previous Investigations

No previous investigations have been conducted at the Site that are pertinent to this project.

2.1.9 Contaminants of Potential Concern

The COPCs for this investigation include metals, dioxins and furans, PCBs, and asbestos.

The COPCs were identified accounting for the byproducts that could be generated from burned building materials or from the building materials themselves. In some areas, the details provided for the construction materials of burned structures are limited or incomplete. Older structures were likely built with asbestos-containing materials. Many of the structures were also constructed with metal construction materials. PCBs could have been released from damaged building transformers or may have been present in building materials, such as in paint and caulk. No building -materials surveys have been conducted in the nine impacted areas.

2.1.10 Media of Potential Concern

The primary media of potential concern are ash and surface soil which may have been impacted by the potential release of COPCs to the environment as a result of buildings being burned in the Woolsey Fire.

Due to the general hydrophobic nature of the COPCs, leaching to groundwater is not anticipated to be a complete pathway.

Secondary media of concern may be surface water and sediment in nearby streams or ephemeral drainages. Potentially contaminated ash or soil may have migrated to nearby drainages during winter 2018/2019. Though surface water and sediment are not primary media of concern in this investigation and no surface water or sediment sampling is planned, the spatial distribution of COPC concentrations in surface soil post removal will be evaluated. If it appears as though elevated concentrations of COPCs could have been release to these streams/drainages then additional investigation and assessment would be considered.

2.2 Scenarios for Potential Human and Ecological Exposure

Current NPS land use within the SAMO is open space for public use. Land use outside of NPS-owned land in the SAMO is a complex mixture of open space, residential and some commercial and is governed by Los Angeles and Ventura County land use plans and various city plans within the SAMO.

2.2.1 Human Receptors and Exposure Pathways

With consideration for current and reasonably expected future land use at and in the vicinity of the nine project areas, the potentially exposed populations are as follows:

On-Site

• Park Residents

• Park Employees

• Park Visitors

• Maintenance Workers

• Construction Workers

Off-Site

• Park Residents

• Park Employees

• Park Visitors

The potential exposure pathways evaluated for each receptor are discussed below and are summarized in Table 4 and on Figure 10.

On-Site

Currently, as a result of the fire, the impacted areas are not being used for residential purposes, for use by park employees, or open to park visitors for recreational activities. However, park residents, park employees and park visitors could be exposed in the future to chemicals in ash or surface soil. Potential routes of exposure to ash/surface soil would be possible through incidental ingestion, dermal contact, and inhalation of airborne particulates.

Following removal activities and potential reconstruction, these areas may also require occasional maintenance activities to be completed. This could include various tasks such as excavations of limited extent and duration. Future potential exposure of maintenance workers to surface soil is assumed to include incidental ingestion, dermal contact, and inhalation of airborne particulates.

During reconstruction or future site redevelopment, exposures to surface soil during larger scale construction activities may be possible. Future potential exposure of construction workers to surface soil is assumed to include incidental ingestion, dermal contact, and inhalation of airborne particulates.

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Off-Site

Off-site receptors include off-site park residents, off-site park employees, and off-site park visitors. These receptors could be exposed to on-site ash/surface soil via inhalation of airborne particulates migrating from on-site areas to off-site areas.

2.2.2 Ecological Receptors and Exposure Pathways

As discussed in Section 2.1.6, potentially exposed ecological receptor groups include terrestrial wildlife (i.e., birds, mammals, reptiles, amphibians) and terrestrial vegetation. The potential exposure routes for terrestrial wildlife include ingestion and direct contact with ash/surface soil and food web exposure.

The receptors and exposure pathways are summarized on Figure 11.

2.2.3 Key CSM Assumptions

• Site-related volatile organic chemicals (VOCs) are not expected to be present in ash or surface soil given the nature of the release (i.e., impacts and deposition as a result of fire). As a result, the exposure scenarios for which removal goals are anticipated to be developed do not include volatilization to indoor air or volatilization to outdoor air inhalation exposures.

• The general hydrophobic nature of the COPCs is such that impact to subsurface soil and leaching to groundwater is not anticipated. As a result, receptor exposure to COPCs is only assumed for ash/surface soil. The CSM may be modified following post-removal confirmation soil sampling, if detected concentrations exceed the RGs.

• Currently, it is assumed that sediment or surface water have not been impacted by COPCs as a result of the fires.

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3 DQO Planning Team and Stakeholders

3.1 DQO Planning Team

The DQO Planning Team for this project includes:

• Stephen Mitchell, P.E., Operations/Environmental Programs Branch Chief, NPS

• J. Colter Chisum, P.E., Chief of Facilities Management, NPS, SAMO

• Patricia Billig, Environmental Protection Specialist, Pacific West Region, NPS

• Greg Nottingham, Environmental Protection Specialist, NPS

• Ryan Dewey, Vice President, Lead Builders, Inc.

• Darren Croteau, Principal Geologist, Terraphase

• Kevin Long, Principal Consultant, Terraphase

• Jonathan Marshak, Senior Staff Geologist, Terraphase

The DQO process is iterative, and team members may be added or changed during the project in order to address technical issues not initially identified.

3.2 Decision-Makers

The decision-makers have the ultimate authority for making final decisions based on the recommendations of the DQO Planning Team. The decision-makers for this project are:

• Stephen Mitchell, P.E. – Operations/Environmental Programs Branch Chief, NPS

• J. Colter Chisum, P.E., Chief of Facilities Management, NPS, SAMO

3.3 Stakeholders

Stakeholders are parties who may be affected by the results of the investigation and/or persons who may later use the data resulting from the investigation. The stakeholders for this project include the public who may use these areas for recreational purposes, local tribes (i.e., the Chumash and the Tongva)2, local agency parks, university study reserves, and private property conservation easements with land in close proximity to the impacted areas.

2 https://www.nps.gov/samo/learn/historyculture/nativeamericanindians.htm

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4 Data Quality Objectives The DQO process specifies anticipated project decisions, the data quality required to support those decisions, specific sample types and numbers needed, data collection requirements, and analytical techniques necessary to generate the specified data quality. The process also ensures that the resources required to generate the data are justified.

The DQO process consists of the following seven steps:

1. State the Problem

2. Identify the Goal of the Investigation

3. Identify the Information Inputs

4. Define the Boundaries of the Investigation.

5. Develop the Analytic Approach

6. Specify Performance or Acceptance Criteria

7. Develop the Plan for Obtaining Data

4.1 State the Problem(s)

Burned debris and ash resulting from the Woolsey Fire is present at each of the nine areas. It is unknown whether, and to what extent, the ash contains elevated levels of COPCs that could have an impact on disposal options for this material following removal. Also, COPCs present in the ash may have been released to surface soil as a result of the Fire. It is also unknown whether, and to what extent, these possible releases to the environment could have resulted in COPC concentrations in ash and surface soil that could present an unacceptable risk to human health or the environment. Determination of the existing and post-cleanup conditions are needed to support the complete cleanup of these areas.

4.2 Identify the Goal(s) of the Investigation

The goals of this investigation are as follows:

• Characterize the nature and extent of site-related COPCs in ash, prior to performing response actions, in order to facilitate proper off-site disposal of the ash/debris;

• Characterize the concentrations of naturally occurring metals concentrations in soil in the vicinity of each of the nine project areas to support development of removal goals; and,

• Characterize the nature and extent of site-related COPCs in surface soil, following the performance of response activities, to confirm that post-cleanup conditions meet the forthcoming proposed removal goals.

Based upon these goals, the principal investigation questions for this investigation are as follows:

1. What is the range of naturally occurring metals concentrations in surficial soil in vicinity of each project area?

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2. What is the nature and extent of COPC concentrations in ash as a result of releases to the environment from the Fire?

3. What is the nature and extent of COPC concentration in surface soil, following the implementation of response activities, as a result of releases to the environment from the Fire?

4. Following the implementation of response activities, do site-related COPCs in surface soil pose an unacceptable risk to human or ecological receptors under current or reasonably expected future land use?

4.3 Identify Information Inputs

4.3.1 Previous Data Usability

No previously obtained laboratory analytical data are available.

4.3.2 Data to be Collected in the Current Investigation

There are two distinct sampling phases for this investigation.

Ash and Background Soil Sampling

Initially, samples of ash will be collected and analyzed from eight of the nine project areas to characterize the nature and extent of site-related COPC concentrations and facilitate disposal as hazardous or non-hazardous material during response activities. Ash is not present at Circle X Ranch and no ash sampling is proposed at this area. In parallel with this effort, soil samples will also be collected from areas expected to have been unimpacted by fire debris in order to determine the range of naturally occurring metal concentrations in soil. The background soil samples will also inform the development of removal goals.

Figures 2 to 9 show the nine project areas and the location of the burned structures. Ash samples will be collected at eight of the nine project areas according to Table 3 of the Statement of Work (NPS 2019).

Table 1 provides a summary of ash samples that will be collected from each area. A minimum of two samples will be collected for each project area, based on communication with disposal facilities on sampling requirements. During a Site visit conducted with NPS on November 13, 2019, Terraphase noted that little to no ash is present in some of the areas, including the former restroom at Rocky Oaks (Figure 4), the former vault restroom at Arroyo Sequit (Figure 5), the former chicken coup and corral area at Morrison Ranch (Figure 7) and at the Dragon Site (Figure 9). According to the Statement of Work (NPS 2019), each of these features was designated for ash sampling. However, ash samples may not be collected at some of these areas due to the limited or non-existent ash. No ash samples are proposed for Circle X Ranch, per Table 3 of the Statement of Work (NPS 2019), due to limited or non-existent ash.

The number of samples proposed for collection during this phase of investigation is as follows:

• Up to 16 ash samples will be collected from the vicinity of 28 structures at the following eight areas (analyzed for metals, [including one sample per area (8 samples) that will be analyzed for hexavalent chromium [CrVI], dioxins and furans, PCBs, and asbestos): Paramount Ranch, Peter

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Strauss Ranch, Rocky Oaks, Cooper Brown, Arroyo Sequit, Morrison Ranch, Miller Property and Dragon Property (Figures 2, 3, 4, 5, 7, 8 and 9). 2 samples will be collected from each area;

• 90 background soil samples will be collected from the following six areas (analyzed for metals, including 20% of samples (3 samples per area) that will be analyzed for CrVI): Arroyo Sequit, Dragon Property, Paramount Ranch, Peter Strauss Ranch, Rocky Oaks, Morrison Ranch (Figures 2, 3, 4, 5, 7 and 9). 15 samples will be collected from each area.

Post-Removal Action Soil Sampling

The second sampling phase will involve the collection of surface soil samples from beneath, and in the immediate vicinity of, the burned structures following the removal of debris and ash. The surface soil samples will also be analyzed for COPCs.

Figures 2 to 9 show the nine project areas and the location of the burned structures.