FINAL RADIOLOGICAL CHARACTERIZATION OF SOILS AREA IV AND THE NORTHERN BUFFER ZONE AREA IV RADIOLOGICAL STUDY SANTA SUSANA FIELD LABORATORY VENTURA COUNTY, CALIFORNIA Prepared for: U.S. Environmental Protection Agency Region 9 75 Hawthorne Street San Francisco, California 94105 Prepared by: HydroGeoLogic, Inc. 5023 North Parkway Calabasas Calabasas, California 91302 December 21, 2012 This page was intentionally left blank. TABLE OF CONTENTS Page 1.0 INTRODUCTION ................................................................................. 1-1 1.1 PURPOSE AND OBJECTIVES ....................................................... 1-1 1.2 LIMITATIONS ........................................................................... 1-2 1.3 REPORT ORGANIZATION ........................................................... 1-2 2.0 SITE 2.1 2.2 2.3 2.4 3.0 STUDY AREA INVESTIGATION METHODOLOGY.................................... 3-1 3.1 NATURAL AND CULTURAL RESOURCES MONITORING ................ 3-1 3.1.1 Natural Resources Monitoring ............................................... 3-1 3.1.2 Cultural Resources Monitoring .............................................. 3-2 3.2 IDENTIFICATION OF RADIONUCLIDES OF CONCERN ................... 3-4 3.3 LINES OF EVIDENCE USED TO SELECT SAMPLE LOCATIONS ........ 3-5 3.3.1 Historical Site Assessment ................................................... 3-6 3.3.2 Aerial Photographic Analysis ................................................ 3-7 3.3.3 Gamma Scanning............................................................... 3-8 3.3.4 Geophysical Survey............................................................ 3-8 3.4 SOIL AND SEDIMENT SAMPLING ................................................ 3-8 3.4.1 Round 1 Soil and Sediment Sampling ...................................... 3-9 3.4.1.1 Targeted Surface and Subsurface Soil Samples ............ 3-10 3.4.1.2 Random Surface Sampling..................................... 3-10 3.4.1.3 Sediment Sampling .............................................. 3-11 3.4.2 Round 2 Soil and Sediment Sampling .................................... 3-11 3.4.2.1 Radiological Trigger Levels ................................... 3-11 3.4.2.2 Surface and Subsurface Soil Step-out Sampling Locations.......................................................... 3-12 3.4.2.3 Sediment Step-out Locations .................................. 3-13 3.5 QUALITY ASSURANCE/QUALITY CONTROL .............................. 3-13 3.5.1 Laboratory Quality Control Elements .................................... 3-14 3.5.2 Quality Control Samples .................................................... 3-14 3.5.2.1 Field Duplicates ................................................. 3-14 3.5.2.2 Equipment Rinsate and Source Water Blanks .............. 3-14 3.5.3 Data Validation ............................................................... 3-15 BACKGROUND ........................................................................... 2-1 SITE LOCATION AND DESCRIPTION ............................................ 2-1 SITE HISTORY........................................................................... 2-1 REGULATORY HISTORY ............................................................ 2-2 ENVIRONMENTAL SETTING ....................................................... 2-3 2.4.1 Soil Types and Topography .................................................. 2-3 2.4.2 Surface Hydrology ............................................................. 2-3 2.4.3 Geology .......................................................................... 2-5 2.4.3.1 Chatsworth Formation............................................ 2-6 2.4.3.2 Santa Susana Formation .......................................... 2-6 Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 i HydroGeoLogic, Inc. 12/21/2012 TABLE OF CONTENTS (Continued) Page 3.5.4 3.5.3.1 Data Validation Methods ...................................... 3-16 Evaluation of Split Samples ................................................ 3-16 4.0 ROUND 1 AND ROUND 2 ANALYTICAL RESULTS .................................. 4-1 4.1 DATA QUALITY EVALUATION ................................................... 4-1 4.2 FIELD ACTION LEVELS ............................................................. 4-3 4.3 RADIONUCLIDES EXCEEDING FIELD ACTION LEVELS ................. 4-3 4.3.1 Cesium-137 ..................................................................... 4-4 4.3.2 Strontium-90 .................................................................... 4-7 4.3.3 Plutonium-239/240 .......................................................... 4-10 4.3.4 Cobalt-60 ...................................................................... 4-12 4.3.5 Europium-152 ................................................................ 4-13 4.3.6 Plutonium-238 ................................................................ 4-14 4.3.7 Americium-241 ............................................................... 4-14 4.3.8 Curium-243/244 .............................................................. 4-15 4.3.9 Single Occurrence Radionuclides ......................................... 4-16 4.3.10 Naturally Occurring Radioactive Material .............................. 4-16 4.3.11 Likely Chemical and Decontamination and Decommissioning Zones ........................................................................... 4-17 5.0 SUMMARY ........................................................................................ 5-1 6.0 REFERENCES ..................................................................................... 6-1 LIST OF TABLES Table 3.1 Soil Samples Collected and Analyzed in Area IV Study Area Table 4.1 Table 4.2 Table 4.3 Radionuclides of Concern Field Action Levels Surface Soil Analytical Results Exceeding Field Action Levels Subsurface Soil Analytical Results Exceeding Field Action Levels Table 5.1 Radiological Areas of Interest Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 ii HydroGeoLogic, Inc. 12/21/2012 LIST OF FIGURES Figure 1.1 Site Location Map Figure 2.1 Figure 2.2 Figure 2.3 Figure 2.4 Figure 2.5 Adjacent Populated Areas Map Area IV Study Area Subareas Topographic Map Drainage Pathway Map Geologic Map Figure 4.1 Figure 4.2 Figure 4.3 Figure 4.4 Cesium-137 Round 1 and Round 2 Surface Soil and Sediment Results Cesium-137 Round 1 and Round 2 Subsurface Soil and Sediment Results Strontium-90 Round 1 and Round 2 Surface Soil and Sediment Results Strontium-90 Round 1 and Round 2 Subsurface Soil and Sediment Results Plutonium-239/240 Round 1 and Round 2 Surface Soil and Sediment Results Plutonium-239/240 Round 1 and Round 2 Subsurface Soil and Sediment Results Cobalt-60 Round 1 and Round 2 Surface Soil and Sediment Results Cobalt-60 Round 1 and Round 2 Subsurface Soil and Sediment Results Europium-152 Round 1 and Round 2 Surface Soil and Sediment Results Europium-152 Round 1 and Round 2 Subsurface Soil and Sediment Results Plutonium-238 Round 1 and Round 2 Surface Soil and Sediment Results Americium-241 Round 1 and Round 2 Surface Soil and Sediment Results Americium-241 Round 1 and Round 2 Subsurface Soil and Sediment Results Curium-243/244 Round 1 and Round 2 Surface Soil and Sediment Results Curium-243/244 Round 1 and Round 2 Subsurface Soil and Sediment Results Figure 4.5 Figure 4.6 Figure 4.7 Figure 4.8 Figure 4.9 Figure 4.10 Figure 4.11 Figure 4.12 Figure 4.13 Figure 4.14 Figure 4.15 Figure 5.1 Select Radionuclides of Concern Round 1 and Round 2 Surface and Subsurface Soil and Sediment Results Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 iii HydroGeoLogic, Inc. 12/21/2012 LIST OF APPENDICES Appendix A Appendix B Appendix C Appendix D Appendix E Appendix F Appendix G Appendix H Appendix I Appendix J Appendix K Appendix L Technical Memorandum, Subarea 3, Soil Sample Results Technical Memoranda, Subarea 5A, Round 1 and 2 Soil Sample Results Technical Memoranda, Subarea 5B, Round 1 and 2 Soil Sample Results Technical Memoranda, Subarea 5C, Round 1 and 2 Soil Sample Results Technical Memoranda, Subarea 5D, Round 1 and 2 Soil Sample Results Technical Memoranda, Subarea 6, Round 1 and 2 Soil Sample Results Technical Memoranda, Subarea 7, Round 1 and 2 Soil Sample Results Technical Memoranda, Subarea 8, Round 1 and 2 Soil Sample Results Technical Memorandum, Northern Buffer Zone Soil Sample Results Technical Memorandum, Deep Borehole Soil Sample Results Development and Use of Radionuclide Reference Concentrations Background Threshold Value and Radionuclide Selection Rationale Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 iv HydroGeoLogic, Inc. 12/21/2012 LIST OF ACRONYMS AND ABBREVIATIONS Ag Am AOC silver americium Administrative Order on Consent Ba bgs BTV barium below ground surface background threshold value C Cf Cm Co Cs carbon californium curium cobalt cesium DOE DQO DTSC Department of Energy data quality objective Department of Toxic Substance Control EDD ETEC Eu electronic data deliverable Energy Technology Engineering Center europium FAL FSP field action level Field Sampling Plan GEL GPS GRAY GEL Laboratories, LLC global positioning system gamma radiation anomaly H-3 HGL HSA tritium HydroGeoLogic, Inc. Historical Site Assessment K KEWB potassium Kinetic Experiment Water Boiler Lc LCRZ LD&DZ critical level likely chemical remediation zone likely decontamination and decommissioning zone MARLAP MDC MQO NAA Multi-Agency Radiological Laboratories Analytical Protocols minimum detectable concentration measurement quality objective North American Aviation Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 v HydroGeoLogic, Inc. 12/21/2012 LIST OF ACRONYMS AND ABBREVIATIONS (Continued) NASA NBZ Ni NORM NPDES National Aeronautical and Space Administration Northern Buffer Zone nickel naturally occurring radioactive material National Pollutant Discharge Elimination System pCi/g PGRAY Pu picocuries per gram potential gamma radiation anomaly plutonium QA QAPP QC quality assurance quality assurance project plan quality control Ra RMHF Rn RRC RTL RWQCB radium Radioactive Materials Handling Facility radon radionuclide reference concentration radiological trigger level Regional Water Quality Control Board SB990 SMP SNAP Sr SRE SSFL STIR Senate Bill 990 Site Management Plan Systems for Nuclear Auxiliary Power strontium Sodium Reactor Experiment Santa Susana Field Laboratory Shield Test and Irradiation Reactor TAL Te Th TM TPC TestAmerica Laboratories, Inc. tellurium thorium technical memorandum The Palladino Company, Inc. U UCL USEPA USFWS uranium upper confidence limit U.S. Environmental Protection Agency U.S. Fish and Wildlife Service Validata Validata Chemical Services, Inc. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 vi HydroGeoLogic, Inc. 12/21/2012 FINAL RADIOLOGICAL CHARACTERIZATION OF SOILS AREA IV AND THE NORTHERN BUFFER ZONE AREA IV RADIOLOGICAL STUDY SANTA SUSANA FIELD LABORATORY VENTURA COUNTY, CALIFORNIA 1.0 INTRODUCTION The U.S. Environmental Protection Agency (USEPA) conducted an extensive radiological characterization study of the Santa Susana Field Laboratory (SSFL) at Area IV and the Northern Buffer Zone (NBZ) located in Ventura County, California (Figure 1.1). SSFL Area IV consists of 290 acres, and the NBZ consists of a 182-acre tract of naturally vegetated land. The Boeing Company owns both Area IV and the NBZ. Collectively, these areas are referred to as the Area IV Study Area. The USEPA conducted this study pursuant to federal legislative mandate HR2764, the Consolidated Appropriations Act of 2008, and the authority granted under the Comprehensive Environmental Response, Compensation, and Liability Act and subsequently the Administrative Order on Consent (AOC) for Remedial Action (DTSC, 2010). This work was executed by HydroGeoLogic, Inc. (HGL) under a USEPA Region 7 Architect and Engineering Services Contract EP-S7-05-05, Task Order 0038, Amendment 0004, being administered and managed by USEPA Region 9. HGL is USEPA’s contractor on this project. 1.1 PURPOSE AND OBJECTIVES The Area IV Radiological Study was conducted to characterize radionuclide concentrations within the Area IV Study Area. The Area IV radiological study consisted of completing an Historical Site Assessment (HSA); conducting a gamma radiation survey of accessible ground surfaces; conducting a geophysical survey of targeted locations; and collecting and analyzing soil, groundwater, surface water, and sediment samples. The results of the HSA, gamma radiation scanning, geophysical survey, historical aerial photographic analysis, and groundwater sampling are detailed in the following documents for the Area IV Radiological Study: • • • • • Final Historical Site Assessment (HGL, 2012a), Final Geophysical Investigation Report (HGL, 2011b), Aerial Photographic Analysis of Santa Susana Field Laboratory (USEPA, 2010), Final Gamma Radiation Scanning Report (HGL and TPC, 2012b), and Final Groundwater Report (HGL, 2012c). Analytical results for the sediment samples will be documented in the Surface Water and Sediment Sample Results Report to be submitted under separate cover. This report describes the sampling regime and analytical results of surface soil and subsurface soil samples collected from potential areas of radiological contamination. Sediment analytical Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 1-1 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California data collected from drainages within the Area IV Study Area have also been included in this evaluation. The primary objective of the soil sampling effort was to evaluate the nature of potential radiological contamination in soil and drainage sediment that may have resulted from past nuclear operations and research activities in the Area IV Study Area. To meet this objective, soil and sediment samples were collected during two rounds of sampling. The initial Round 1 sampling event consisted of collecting samples at specific, targeted locations identified from the findings of the HSA, gamma radiation scanning survey, geophysical survey, the aerial photographic analysis, and stakeholder requests. The Round 2 sampling consisted of collecting step-out samples to delineate radionuclide concentrations in soils adjacent to Round 1 sample locations that exhibited concentrations above the project decision levels, called radiological trigger levels (RTL). RTLs were used during the sampling events to identify locations of potential concern in the absence of defined cleanup values. The targeted and step-out soil sampling locations, justification, and supporting lines of evidence were outlined in subarea-specific addendums to the Final Field Sampling Plan (FSP) Soil Sampling (HGL, 2012d). Each subarea-specific addendum detailed the planned soil sampling effort for the subarea and took into account stakeholder input. Soil sampling efforts were conducted in accordance with the Final FSP, the subarea-specific FSP addenda, and the Final Quality Assurance Project Plan (QAPP) for Soil Sampling (HGL, 2012e). 1.2 LIMITATIONS This report is intended to characterize radiological areas of interest from past site activities within the Area IV Study Area. This report is not intended to identify remedial locations nor indicate areas of contamination. These determinations will be made at a future date by the State of California Department of Toxic Substances Control (DTSC). The activities described in this report were conducted in general accordance with current regulatory guidelines and the standard-of-care exercised by environmental consultants performing similar work in the project area. The findings discussed in this report were derived from data collection efforts conducted with commercially available sampling and analysis equipment, techniques, and procedures available at the time the investigation was conducted. The samples collected and used for analysis, and the observations made, are believed to be representative of the Area IV Study Area; however, conditions can vary significantly between sampling locations, thus, conditions not observed or described in this report may be encountered during subsequent activities. 1.3 REPORT ORGANIZATION This report consists of Sections 1.0 through 6.0 and Appendices A through L. Referenced tables and figures are provided in separate, tabbed sections. The Appendices include the soil sampling results technical memoranda (TM) for each subarea, the Development and Use of Radionuclide Reference Concentrations (RRC) paper, and the Background Threshold Values (BTV) and Radionuclide Selection Rationale paper. The contents of each section are summarized below: • Section 1.0, Introduction. organization of this report. Santa Susana Field Laboratory Radiological Characterization of Soils Describes the purpose and objectives, limitations, and U.S. EPA Region 9 1-2 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California • • • • • Section 2.0, Site Background. Describes the site location, site and regulatory history, selection of radionuclides of concern and environmental setting including surface hydrology, soil types, topography, and geology. Section 3.0, Study Area Investigation Methodology. Discusses natural and cultural resources, lines of evidence used to identify soil sample locations, sample collection process during the Round 1 and Round 2 soil sampling events, and the quality assurance (QA)/quality control (QC) procedures employed during sample collection and laboratory analysis. Section 4.0, Round 1 and 2 Analytical Results. Describes the evaluation approach, and discusses the analytical results, radiological contamination areas, and radiological areas of interest. Section 5.0, Summary. Summarizes the radiological contamination areas for the entire Area IV Study Area and general considerations. Section 6.0, References. Lists the documents cited in this report. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 1-3 HydroGeoLogic, Inc. 12/21/2012 This page was intentionally left blank. HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California 2.0 SITE BACKGROUND 2.1 SITE LOCATION AND DESCRIPTION The SSFL is located in southeastern Ventura County, California, approximately 30 miles northwest of Los Angeles between the Simi and San Fernando valleys in the Simi Hills (Figure 1.1). Residential developments are located near the southern, northern, and eastern boundaries of the site (Figure 2.1). The SSFL occupies 2,850 acres of rocky (sandstone) terrain with approximately 700 feet of topographic relief. Specifically, the study was focused on Area IV and the adjacent NBZ referred as the Area IV Study Area. The Area IV Study Area is composed of approximately 471 acres (290 acres in Area IV and 181 acres in the NBZ) that vary from relatively flat to steep relief and rugged terrain. The elevation of the Area IV Study Area is between 1,880 feet and 2,150 feet above mean sea level. The Area IV Study Area was initially divided into eight subareas based on existing Resource Conservation and Recovery Act Facility Investigations. For the radiological characterization study, USEPA elected to further subdivide these eight subareas into 12 subareas based on features such as roads, drainage pathways, and building use as follows: • • • • • • Subarea 3 Subarea 5A Subarea 5B Subarea 5C Subarea 5D-North Subarea 5D-South • • • • • • Subarea 6 Subarea 7 Subarea 8-North Subarea 8-South NBZ East NBZ West The subareas are depicted on Figure 2.2. Results from each sampling event are presented in separate TM by subarea and are included in Appendices A through J. The results for Subareas 5D-North, 5D-South, 8-North, 8-South, NBZ East and NBZ West were presented in three TMs for each sampling event; Subarea 5D, Subarea 8 and NBZ (Appendices E, H and I). 2.2 SITE HISTORY As a component of this radiological study, USEPA conducted an extensive HSA to document the site history and past facility operations, as well as to provide technical information for selection of soil samples. This section was derived from the USEPA’s HSA and provides a very brief summary of the site history (HGL, 2012a). Before development of the SSFL site, the area was used for ranching. In approximately 1948, North American Aviation, Inc. (NAA) began development of the site for the design, development, and testing of liquid propellant rocket engines. The facilities at the SSFL site supported many major space programs, from the earliest satellite launches to the Space Shuttle. The Rocketdyne Division of NAA operated these portions of the SSFL site until approximately 1996 when Rocketdyne merged into The Boeing Company. Since Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 2-1 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California approximately 1996, operations at the site have been conducted by The Boeing Company (ETEC, 2010 and HGL, 2012a). The SSFL is separated into four administrative areas. The Boeing Company owns all of Area I, except for 42 acres which are owned by the United States and under the administrative control of the National Aeronautics and Space Administration (NASA). Area II is also owned by the United States and under the control of NASA but operated by The Boeing Company. The Boeing Company owns and operates Areas III and IV. Areas I, II, and III were also used by The Boeing Company, NASA, and the Department of Defense for rocket engine and laser testing. Under contract to the Department of Energy (DOE), NAA also operated the Energy Technology Engineering Center (ETEC), located exclusively in Area IV, for researching, developing, and constructing nuclear reactors and associated equipment for harnessing nuclear energy through its Atomics International Division (NAA, 1960). Until its closure in 1996, DOE was responsible for operating ETEC. ETEC represented the group of facilities owned by DOE that were used for nuclear research and other experimental activities within Area IV. From the mid-1950s until the mid-1990s, DOE and its predecessor agencies were engaged in or sponsored nuclear operations including the development, fabrication, disassembly, and examination of nuclear reactors, reactor fuel, and other radioactive materials. Associated experiments included large-scale sodium metal testing for fast breeder reactor components. Nuclear operations at ETEC included 10 nuclear research reactors, including the Sodium Reactor Experiment (SRE), seven critical facilities, the Hot Laboratory, the Nuclear Materials Development Facility, the Radioactive Materials Handling Facility (RMHF), and various test and radioactive material storage areas. Each of these facilities has been described in the Final HSA volumes II through VIII (HGL, 2012a). All nuclear research in Area IV was terminated in 1988 when DOE shifted its focus from research to decontamination and decommissioning activities. Decontamination and decommissioning of the sodium test facilities started in 1996 when DOE determined that the entire ETEC facility was surplus to its mission. DOE began formal cleanup and closure of its facilities in Area IV in preparation for returning the property to The Boeing Company. The HSA report includes a summary of past operations and activities involving radioactive materials for all subareas. The results of past radiological surveys performed in Area IV are also summarized. Radiological surveys have been performed for several purposes including health and safety, characterization, remedial action support, and release. 2.3 REGULATORY HISTORY The Atomic Energy Commission was abolished by the Energy Reorganization Act of 1974 and was succeeded by the Energy Research and Development Administration (now part of DOE) and Nuclear Regulatory Commission. Radiological contamination in Area IV has been sampled and analyzed, including radiological surveys conducted in 1988 and again in 1995 as well as radiological release surveys within the footprints of former radiological facilities. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 2-2 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California In August 2007, DTSC, as the lead regulatory agency, and The Boeing Company, DOE, and NASA, as potential responsible parties, entered into a Consent Order for Corrective Action governing the remediation of chemical contamination at the SSFL (DTSC, 2007). In October 2007, California enacted SB990 entitled “Cleanup of Santa Susana Field Laboratory” which became effective on January 1, 2008. SB990 asserted state jurisdiction over the SSFL remediation and required calculating the cumulative risk from radiological and chemical contaminants to the lower of either suburban residential or rural residential (agricultural) land use scenarios, whichever produces the lower permissible residual concentration for each contaminant. In December 2010, DTSC signed an AOC with DOE to address the federal radiological and chemical remediation of soil in the Area IV Study Area to background values for both radiological and chemical contaminants by the year 2017). The Boeing Company and the USEPA are not a party to the AOCs. 2.4 ENVIRONMENTAL SETTING 2.4.1 Soil Types and Topography The SSFL is located on a ridge within the Transverse Ranges physiographic province. The facility is approximately 850 feet above the valleys to the north and south. While the laboratories and other facilities within Area IV are generally located on relatively flat ground, local relief can be up to approximately 270 feet. In the Area IV Study Area, the highest elevation (2,150 feet above mean sea level) is along the southern boundary (Figure 2.3). Along the northwest boundary, the land slopes steeply away to undeveloped land. The relatively flat area in the southern part of the Area IV Study Area is called “Burro Flats.” The parent material of the soil in the Area IV Study Area consists of weathered bedrock, colluviums and alluvium derived from the Chatsworth Formation. According to the Natural Resources Conservation Service, approximately 40 percent of the Area IV Study Area is classified as sedimentary rock outcrop. The two predominant soil types in the Area IV Study Area are a sandy loam of the Saugus series and a loam of the Zamora series. The Saugus series soils consists of deep, well drained soils that usually forms on dissected terraces and foothills and are moderately permeable. The sandy loam of the Saugus series usually has slopes of five to 30 percent. The Zamora series soils are typically well drained loam that forms on nearly level grade or on strongly sloping fans and terraces. The Zamora series in the Area IV Study Area has slopes that range from two to 15 percent (USDA, 2003). 2.4.2 Surface Hydrology Surface water drainage in the northern portion of the Area IV Study Area flows north into Meier Canyon, which is a tributary to the Arroyo Simi, flowing westward and terminating in the Pacific Ocean. Drainage of the majority of the Area IV Study Area flows to the southeast into the Bell Creek drainage system as suggested by the location of the northeast-southwest trending drainage divide (Figure 2.4). Bell Creek is the headwater and tributary of the Los Angeles River, which flows south and eastward terminating in the Pacific Ocean. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 2-3 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Given the topographic divide and topographical rises to the east and west of Area IV, there is no drainage directly to the west or east from the Area IV (USGS, 1952). A site reconnaissance during the Area IV Radiological Study surface water sampling program determined there was no surface water drainage from Area IV to the west into Runkle Canyon. However, a small area, approximately two acres in the southwest corner of the NBZ, was identified where surface water does flow to the west. The California Regional Water Quality Control Board (RWQCB) has issued waste discharge permits to the SSFL since 1958. Starting in 1984, the RWQCB began issuing surface water discharge permits to the SSFL under the National Pollutant Discharge Elimination System (NPDES). Surface water discharges from the site are monitored at 18 NPDES locations, and according to the RWQCB, from 1998 through 2006 (RWQCB, 2006), discharges from the SSFL have continually exceeded effluent limits for dioxin, heavy metals, and other pollutants. In July 2007, the Los Angeles RWQCB issued an order requiring The Boeing Company to cease and desist all discharges of contaminants that exceed specified effluent limits (Weston Solutions, Inc., 2007). Of these 18 historical surface water discharge outfall locations there are ten that receive surface water from Area IV or the NBZ. Outfall locations 3, 4, 5, 6, and 7 receive surface water from the northern portion of Area IV. Outfall locations 9 and 10 receive surface water from the NBZ. Outfall locations 17, 18 and 2 receive surface water from the southern portion of Area IV (Figure 2.3). Outfall locations 3, 4, 6, 10, 18 and 2 receive surface water from former operational areas and are specifically designed multimedia filtration systems engineered to filter the surface water before it travels downgradient. Currently, surface water from these outfalls is diverted to the Silvernale settling pond located in Area III as a result of the Los Angeles RWQCB cease and desist order issued in 2007 (Figure 2.3). Outfall locations 5 and 7 are lined settling ponds and are designed to retain surface water so it can be transferred to the Silvernale pond. Outfall location 9 is strictly an NPDES sampling location and is not designed to filter or retain surface water. The NPDES outfall permitting and monitoring program is regulated by the Los Angeles RWQCB. The majority of surface drainage within Area IV is through man-made and natural ditches and swales that lead to natural streambeds. The drainage from some former operational areas is directed through various settling ponds and outfall locations. The following subsections provide a brief summary of these operational areas and their associated settling ponds and outfalls. Former Sodium Disposal Facility Surface water runoff in the vicinity of the Former Sodium Disposal Facility area flows to the east-northeast. Outfall locations 5 and 6 receive water from the former sodium disposal facility before the water flows into the NBZ. Outfall 5 is a settling pond. Outfall 6 is a multimedia filtration system engineered to filter the surface water before it travels downgradient. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 2-4 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Former Building 4373 (Hot Lab) and Building 4055 Runoff from the vicinity of former Building 4373 (Hot Lab) and Building 4055 flows to the east through the ditch on the south side of G street and the ditches on either side of H and I streets. The runoff water flows through these ditches, through the former Space Technology Laboratory IV complex in Area III, and into the R2 settling ponds located in Area II. Building 4009, Building 4100, and the 56 Landfill Runoff in the vicinity of Building 4009, Building 4100 and the 56 Landfill drains to the north along the west side of the landfill, into the NBZ. Outfall 7 is located approximately 70 feet north of building 4100 and only receives surface water from the vicinity of Building 4100. Radioactive Materials Handling Facility Runoff within the RMHF fenced area generally flows from east to west across the site to a storm drain culvert along the western perimeter of the site. Surface water flow to the northern perimeter drains into an asphalt-lined swale that leads to the storm drain culvert. Prior to 2006, the culvert drained to an asphalt-lined channel that conveyed surface water to the RMHF holding pond (RMHF 4614 Holdup Pond). The Holdup Pond had a capacity of approximately 30,000 gallons and was used to contain storm water runoff and any accidental releases. It was sealed with coated asphalt to prevent leakage and equipped with a radiation monitor connected to an alarm system to warn if any radioactive contamination enters the pond. The RMHF 4614 Holdup Pond and drainage channel were removed in 2006. The culvert now drains into an aboveground pipeline that conveys water to a 1,500-gallon polyurethane aboveground storage tank. After the accumulated storm water is tested for radionuclides, it was pumped from the aboveground storage tank to B Street where it enters a pipeline that discharges to a lined drainage along 17th Street. Drainage follows 17th Street to G Street and then continues through lined and unlined channels to the 17th Street Drainage. Sodium Reactor Experiment Complex The majority of the runoff from the SRE Complex is captured in the SRE pond which is located approximately 400 feet east of the complex. Runoff from the northern portion of the SRE complex flows to the east via a small asphalt-lined ditch, through Outfall 4, and into the SRE Pond. Runoff from the southern portion generally flows to the east via drains and underground culverts. The culverts lead to a concrete-lined ditch that diverts runoff around Outfall 4 and into the SRE Pond. Overflow from the pond is to the east-north east via a natural drainage that leads to Meiers Canyon. Old and New Conservation Yards Runoff from the Old and New Conservation Yards flows to the south-southeast via a natural unlined drainage that leads into Area III and, subsequently, into Silvernale Pond. Surface water in the northern portion of the Old Conservation Yard flows to the north and into the Northern Buffer Zone. 2.4.3 Geology The SSFL is situated within the Transverse Ranges physiographic province, approximately 30 miles north of downtown Los Angeles (Baily and Jahns, 1954). Two geologic formations Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 2-5 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California underlie the Study Area, the Cretaceous Chatsworth Formation and the Tertiary Santa Susana Formation. The Chatsworth Formation underlies approximately 80 percent of the Study Area. The following descriptions are derived from the Preliminary Geologic Map of the Los Angeles 30 feet by 60 feet Quadrangle, Southern California (Yerkes and Campbell, 2005). A geologic map of the area is presented as Figure 2.5. The SSFL is located on the south flank of an approximately east-west striking, westward plunging syncline. There are three categories of geologic structures present in the SSFL faults/fault zones, deformation bands, and structures (MWH, 2007). The fault zones and deformation features displace primary geologic features, the former showing displacement of at least five feet and the later with minimal located displacement (less than 6 inches). Mapped faults in the SSFL are presented on Figure 2.5. The Burro Flats Fault places the Chatsworth Formation in structural contact with the Santa Susana Formation in the southwest portion of the Area IV Study Area. 2.4.3.1 Chatsworth Formation The Chatsworth Formation consists of three unnamed members. The members were deposited by turbidity currents in a deep ocean at depths ranging from 4,000 to 5,000 feet. Turbidity currents cause massive submarine landslides from the continental shelf into submarine canyons which are generally more than a half-mile wide and greater than ten miles in length. During periods without turbidity currents, silt and clay particles from runoff filtered to the ocean floor and formed the siltstone strata found in the formation. Deposited in the late Cretaceous, the Chatsworth Formation is in excess of 6,000 feet thick. The uppermost member is a thick strata of light gray to brown sandstone, which is hard, coherent, arkosic, micaceous, primarily medium grained separated by thin partings of siltstone. The middle member is a gray conglomerate of cobbles of rounded, polished clasts of quartzite, porphyry and granitic rocks in hard rock matrix. The lower member is gray clay shale, crumbly with ellipsoidal fracture where weathered, and may include sandstone strata. 2.4.3.2 Santa Susana Formation The Santa Susana Formation underlies the southwestern most portion of the Area IV Study Area and consists of four members. The unnamed uppermost layer of the Santa Susana Formation consists of gray micaceous claystone and siltstone with a limited number of thin rock beds. Below the uppermost layer lies a second unnamed layer that is made up of tan coherent fine grained rock, which locally contains thin shell-beds and calcareous concretions. Underlying this layer is the Las Virgenes Sandstone Member, which is composed of tan semifriable bedded sandstone and is locally pebbly. The oldest member is the Simi Conglomerate Member. This member contains gray to brown cobble conglomerate with smooth cobbles of quartzite, metavolcanic and granitic rocks in sandstone matrix that locally includes thin lenses of red clay. The Santa Susana Formation also was formed by turbidity currents. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 2-6 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California 3.0 STUDY AREA INVESTIGATION METHODOLOGY 3.1 NATURAL AND CULTURAL RESOURCES MONITORING Several activities associated with the radiological study of the Area IV Study Area had the potential to impact natural and cultural resources. The following subsections describe the procedures used to protect natural and cultural resources during soil sampling activities. 3.1.1 Natural Resources Monitoring The Area IV Study Area is home to many federally listed species and their critical habitat, as well as biological resources protected under other Federal and State laws. The activities conducted by USEPA had the potential to impact protected natural resources, including vegetation cutting, gamma scanning survey, geophysical surveys, surface and subsurface soil sampling, groundwater monitoring well sampling, surface water sampling, and sediment sampling. To minimize the impact to natural resources and riparian habitat within the Area IV Study Area, protection measures were developed and implemented during surveys and sampling activities on the project site, including associated vegetation clearance. USEPA conducted this project pursuant to federal legislative mandate HR2764, the Consolidated Appropriations Act of 2008, and the authority granted under the Comprehensive Environmental Response, Compensation, and Liability Act. Formal consultation under Section 7 of the Endangered Species Act was conducted with the U.S. Fish and Wildlife Service (USFWS), and a Biological Opinion was issued on May 25, 2010 (USFWS, 2010). The USFWS Biological Opinion identified Avoidance and Minimization Measures keyed to each of the proposed activities and federally listed species with potential to occur within the Action Area. USEPA agreed to implement the various components of the Radiological Study in compliance with the Biological Opinion and its requirements. Although not under discretionary approval, USEPA also made efforts to comply with the substantive technical requirements of State of California natural resource protection laws, such as the California Endangered Species Act and California Fish and Game Code Section 1602 for impacts to riparian resources. Additional applicable biological resource laws or regulations to which the project adhered included the Federal Migratory Bird Treaty Act and California Fish and Game Code 3503 and 3503.5 (for protection of nesting birds). Qualified Biological Monitors from Envicom Corporation were retained to assist with species identification and protection as outlined in the Site Management Plan (SMP) (HGL, 2010a). The Biological Monitors inspected the proposed work area for protected plant or animal species or critical habitats requiring protection. These areas were clearly marked with bright red-and-white-striped or pink flags tied to stakes to cordon off the area and to alert personnel to the presence of the protected biological resource (HGL, 2010a). An information sheet was provided to site personnel containing a list of the federal and state species of concern in the Biological Assessment (HGL and Envicom Corporation, 2009) and the Biological Opinion issued by the USFWS (USFWS, 2010). Species at risk but not considered endangered or threatened from site activities were also monitored for protection Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-1 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California through the joint effort of field personnel and the Biological Monitors. The following is a list of plant and animal species that were identified in the field, flagged and avoided: • • • • • • • • • • • • • • • Braunton’s milk-vetch (Astragalus brauntonii) Lyon’s pentachaeta (Pentachaeta lyonii) Spreading navarretia (Navarretia fossalis) California Orcutt Grass (Orcuttia californica) Conejo dudleya (Dudleya abramsii ssp. parva [=> Dudleya parva]) Santa Monica Mountains dudleya (Dudleya cymosa ssp. ovatifolia [inclusive of Dudleya cymosa ssp. agourensis]) Marcescent dudleya (Dudleya cymosa ssp. marcescens) Coastal California gnatcatcher (Polioptila californica ssp. californica) Least Bell’s vireo (Vireo bellii ssp. pusillus) California red-legged frog (Rana aurora ssp. draytonii [=> Rana draytonii]) Quino checkerspot butterfly (Euphydryas editha ssp. quino) Riverside fairy shrimp (Streptocephalus woottonii) Vernal pool fairy shrimp (Branchinecta lynchi) San Fernando Valley spineflower (Chorizanthe paryii var. fernandina) Santa Susana tarplant (Deinandra minthornii) During the migratory season various birds were nesting within the Area IV Study Area. The nesting bird areas were identified, flagged, and continually examined by the Biological Monitor. These areas were avoided until Biological Monitors confirmed the chicks had fledged and left the nest. Once these areas were cleared by the Biological Monitors, the flags were removed and access for field activities was approved. Quarterly Biological Monitors reports were submitted to the USFWS throughout all field activities identifying protected biological resources encountered and detailing the measures implemented to protect these resources. Soil sample locations situated within a biologically protected resource were not collected. In some cases the sample location could be moved a few feet to no longer impact the protected resource. In these instances soil samples were collected and new global positioning system (GPS) coordinates were recorded. 3.1.2 Cultural Resources Monitoring The SSFL was historically occupied by Native Americans and nineteen new archaeological sites and more than 50 isolated artifacts were identified during the course of the EPA Radiological Study. John Minch and Associates, Inc., under subcontract to HGL, provided Archaeological and Native American monitoring for the duration of all ground disturbing activity. Consultation in accordance with Section 106 of the National Historic Preservation Act was conducted throughout the sampling efforts. Cultural Monitors and Native American Advisors/Consultants from local tribes monitored all ground disturbing activity and provided archaeological monitoring support as necessary during the execution of fieldwork. Cultural Monitors were qualified archaeologists who specialized in southern California Native Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-2 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California American artifacts and culture. The Native American Advisors/Consultants were local Southern California tribal representatives from the most likely descendents of the former Native American inhabitants of the SSFL as discussed in the SMP (HGL, 2010a). The consultants were required to have knowledge of local customs, traditions, and religious practices of the Tatavian and/or Fernandeno Indian Tribes and in particular the Eastern Coastal or Ventureno Chumash Indian tribes. Before initiating any site activities Cultural Monitors and Native American Advisors/Consultants inspected each site for cultural resources that could have been adversely affected by site activities including: • • • • Archaeological deposits - soils that contained material evidence of human activity including the remains of houses, hearths, cemeteries, and other features, Artifacts - objects made by people such as whole or broken grinding stones, bowls and tools of various kinds, Rock paintings and carvings that are tied to the landscape, which provide information about the culture of the people who made and used them, and Certain plants and sacred sites - natural features of the landscape that are recognized in local traditions and places with religious significance. Areas of cultural significance were marked with yellow flags tied to wooden stakes to cordon off these areas as protected resources. Identification, avoidance, and protective measures were employed during the execution of field activities at the SSFL site to protect Cultural Resources in accordance with all applicable laws, regulations, and policies as follows: • • • HGL and subcontractor field personnel received training for identifying cultural features, archaeological sites, and artifacts. This training was jointly conducted by the Cultural Monitors and Native American Advisors/Consultants before work began. Cultural resources protection measures were applied during all ground disturbing field activities. All known cultural resources, as identified through previous surveys, as well as all archeological sites and artifacts discovered through the course of this undertaking were avoided. If potential artifacts were identified, the field crew left them in place and notified a Cultural Monitor and/or Native American Advisors/Consultant immediately. All soil samples were inspected by Cultural Monitors and/or Native American Advisors/Consultants to identify and remove any cultural resources from the sample as part of the sample preparation. Upon the completion of fieldwork the Final Report of Cultural Resources Compliance and Monitoring was prepared, discussing the measures taken to protect and any impacts to archeological findings from the cultural surveys within the Area IV Study Area (John Minch and Associates, Inc., 2012). Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-3 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California 3.2 IDENTIFICATION OF RADIONUCLIDES OF CONCERN USEPA developed a list of radionuclides during the SSFL radiological background study. The initial list included a comprehensive list from the Hanford Site in Hanford, Washington (Washington State Department of Health, 1996), with the understanding that radionuclides of concern for SSFL would contain radionuclides actually used or produced at SSFL. The background study list of radionuclides was selected using the following criteria: • • • • The radionuclide was or could have been used or produced at SSFL. The physical state of the radionuclide is not a gas (if the radionuclide is a gas and its parent was not removed from the list, then it was retained). The radionuclide has a half-life greater than one year (if the radionuclide has a half-life of less than one year and its parent was not removed from the list, then it was retained). The SSFL Technical Stakeholder Workgroup elected to keep a specific radionuclide on the list. Recognizing that the background study list of radionuclides contained specific radionuclides highly unlikely to have been used or produced at SSFL or extraordinary radionuclides that were expected to provide limited information at significant cost to the project, in consultation with the Technical Stakeholders, USEPA reduced the total number of radionuclides considered for the radiological study, and proposed two suites of radionuclides for soil analyses. The first was the default suite which included: • • • Radionuclides detectable by gamma spectrometry; Strontium (Sr)-90 (which includes yttrium-90); and Commonly analyzed isotopes of uranium (U), thorium (Th), americium (Am), curium (Cm), and plutonium (Pu). The second was the site-specific suites, which included more than one possible combination of analyses. The site specific analytes and the criteria for selecting the analyte are summarized below: • • • • • • Tritium (H-3) - SRE, Buildings 4010, 4059, 4028, and 4024 and at the site of the H-3 groundwater plume. Carbon (C)-14 - SRE, reactor areas which used graphite, and some percentage of random sampling due to potential drift from C-14 which may have been used in rocket fuels. Nickel (Ni)-59 and Ni-63 - Reactors, the Hot Lab, the burn pit, and where cobalt (Co)60 is observed above background. Technetium-99 - Reactor buildings, the Hot Lab, and the burn pit. Add a small percentage to random samples. Iodine-129 - Hot Lab only. Promethium-147 - Hot Lab and Former Sodium Disposal Facility only. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-4 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California • • • • • • Radium (Ra)-226 and Ra-228 - Based on excursions of bismuth-214 and lead-214 well above background. Uranium-232 - Buildings 4003, 4055, 4093, and the Hot Lab. Neptunium-237 - If any default Pu isotopes are found above their RTL or LUT concentrations. Plutonium-241 - If any default Pu isotopes are found above their RTL or LUT concentrations. Plutonium-236 and Pu-244 - If any default Pu isotopes are found above their RTL or LUT concentrations. Americium-243, Cm-245, and Cm-246 - Only where accelerators were used. During Round 1 soil sampling, all samples were analyzed for the default suite. Round 1 samples collected at specified locations or Round 2 samples meeting the conditions described above were also analyzed for site-specific suite methods based on past facility operations within a given area. Both suites are summarized in Table 2.3 of the Final FSP for Soil Sampling (HGL 2012d). Round 2 sample analyses were conducted to further define exceedances identified during Round 1. The Round 2 analyses were performed using only the method(s) necessary to evaluate the Round 1 exceedance (i.e., a cesium [Cs]-137 exceedance required gamma spectrometric analysis only). Final adjustments to the Radiological Study list of radionuclides were made between the draft final (October 4, 2010) and final (February 17, 2012) versions of the Final FSP for Soil Sampling (HGL 2012d). One adjustment removed eight radionuclides from the default suite gamma spectrometry method: silver (Ag)-108, Ag-108m, barium (Ba)-133, Ba-137m, californium (Cf)-249, radon (Rn)-220, Rn-222, and tellurium (Te)-125m. The radionuclides Ag-108, Te-125m, Ba-137m, Rn-220, and Rn-222, were removed from consideration because they are redundant and are not measured directly, but are assumed to be in a state of secular equilibrium with their parent or progeny radionuclides. The activity concentrations are calculated directly from the reported parent or progeny activity. For example, Ba-137m is calculated directly from Cs-137 and an exceedance or data quality excursion in one result would be repeated in the other. A second adjustment recommended in the Background Study, removed Ag-108m, Ba-133, and Cf-249 due to spectral interference from naturally occurring radionuclides. Due to the timing of implementation of these changes, analytical results for these radionuclides are reported with some of the early Round 1 data but not Round 2 data. 3.3 LINES OF EVIDENCE USED TO SELECT SAMPLE LOCATIONS The selection of targeted soil sample locations for Round 1 soil sampling was based on knowledge of the subarea being investigated and on professional judgment. For this study, the selection of targeted sampling locations was based on a combination of existing data from historical sources and new data collection efforts. Information utilized in determining targeted sample locations included the results of the HSA, gamma radiation survey, geophysical survey, aerial photographic analysis, and reconnaissance activities that were conducted within each subarea before sampling commenced. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-5 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California For each subarea and the NBZ, a subarea-specific Round 1 FSP addendum was prepared with supporting maps showing the following: • • • • • Findings identified in the HSA (HGL, 2012a); Aerial photographic analysis (USEPA, 2010); Past radiological surveys and results of past radiological soil sampling and analysis (HGL, 2012a); Gamma radiation anomalies identified by the gamma radiation survey (HGL and TPC, 2012b); Geophysical anomalies identified by the geophysical survey (HGL, 2011b); and Observations identified by field reconnaissance in each subarea. Each subarea-specific FSP Addendum identified targeted soil sampling locations based on the following: • • • The likelihood that potential radiological soil contamination was present, The technical information and lines of evidence that led to identifying each targeted sample location; and Stakeholder input. A subarea-specific Round 2 FSP addendum was prepared for subareas requiring further delineation of radionuclides identified in soils at concentrations greater than the RTLs. The Round 2 addenda included the findings from the Round 1 soil sampling activities, justifications, and locations of soil samples. 3.3.1 Historical Site Assessment As part of USEPA’s radiological study, a comprehensive HSA was completed for the Area IV Study Area and was documented in subarea-specific HSA TMs (included as volumes II through VIII of the HSA (HGL, 2012a). The objective of the HSA was to conduct comprehensive historical research to identify, collect, organize, and evaluate historical information relevant to nuclear research operations as it may pertain to potential radiological contamination in the Area IV Study Area. Once each subarea-specific HSA was complete, potential areas possibly associated with radiological contamination were identified for Round 1 targeted soil sampling and analysis. The information in the HSA was obtained from the review of more than 100,000 historical documents that describe past facility operational practices as well as facility processes and systems. Each HSA TM also includes findings of interviews with former employees who worked in Area IV. During these interviews, former employees were questioned regarding their knowledge of spills or processes that may have resulted in releases of radionuclides, disposal practices for liquid and solid waste, and identification of areas where radiological investigations should be performed. The interviews were used to assist in the identification of potential release areas (HGL, 2012a). Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-6 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Preliminary findings presented in the HSA TM included: • • • • • Descriptions and locations of potential, likely, or known activities that involved radioactive material, radioactive waste, or mixed waste; Initial Multi-Agency Radiation Survey and Site Investigation Manual (USEPA, 2000) classifications (for example, Class 1, 2, 3) of potentially impacted areas; A site-by-site assessment of the likelihood or “weight of evidence” of radiologically contaminated media; An assessment of the likelihood of potential migration pathways; and, Identification and confirmation of potential radiological contaminants of concern (Section 3.3.1). The information provided in each HSA TM together with comments and recommendations provided by SSFL stakeholders and the general public was used to develop the strategy for surface and subsurface soil sampling and analysis for residual radiological contamination in surface and subsurface soil within each subarea. These recommendations were based only on historical information and not on-the-ground evaluations (HGL, 2012a). 3.3.2 Aerial Photographic Analysis An analysis of historical aerial photographs of the Area IV Study Area was performed by USEPA and used to support the identification of targeted soil sample locations. The process of photographic analysis involved the visual examination and comparison of many components of the photographic image. These components included shadow, tone, color, texture, shape, size, pattern, and landscape context of individual elements of a photograph. The photo analyst identified objects, features, and “signatures” associated with specific environmental conditions or events. The term “signature” refers to a combination of components or characteristics that indicate a specific object, condition, or pattern of environmental significance. Academic and professional training, photo interpretation experience gained through repetitive observations of similar features or activities, and deductive logic of the analyst as well as background information from collateral sources (e.g., site maps, geological reports, and soil surveys) were critical factors employed in the photographic analysis (USEPA, 2010). Based on the review of aerial photos, a list of waste disposal areas, processing areas, open storage areas, fill areas, and impoundments was prepared for the Area IV Study Area. Each location was identified as certain, probable, or possible. Other features included in the analysis of aerial photographs included stains, storage tanks, pipelines, disturbed ground, mounded material, smokestacks, ground scars, building foundations, cleared areas, and buildings. Targeted soil sample locations were identified to investigate all features labeled as “certain” in the aerial photographic analysis. Targeted soil sample locations were also identified to investigate “potential” or “possible” features from the aerial photographic analysis that were co-located with information from other technical information sources (USEPA, 2010). Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-7 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California 3.3.3 Gamma Scanning A gamma radiation scanning survey was performed for 100 percent of the accessible ground surfaces in the Area IV Study Area to identify gamma radiation anomalies (GRAY), in accordance with the Gamma Radiation Scanning Sampling and Analysis Plan (HGL and TPC, 2010b). Approximately 265 acres out of 471.64 acres were scanned within the Area IV Study Area. Gamma radiation emanates from certain man-made and/or naturally occurring radionuclides. Data collected during gamma scanning was evaluated and if a location was found to contain elevated gamma radiation measurements, it was classified as a potential gamma radiation anomaly (PGRAY). The PGRAY was then targeted for further investigation with gamma stationary (static) measurements. The static measurements increased detection sensitivity and the data were analyzed to determine if the PGRAY consisted only of naturally occurring radioactive material (NORM) or man-made radionuclides. PGRAYs consisting of only NORM were identified as "Not a GRAY" and no further action was recommended. PGRAYs consisting of man-made radionuclides were identified as "Confirmed GRAYs" and soil sampling was recommended. A list of locations of GRAYs was prepared for each of the 12 subareas in the Area IV Study Area. Targeted soil sample locations were identified, collected and analyzed to investigate confirmed GRAYs and some PGRAYs. The results of the gamma radiation survey are presented in the Final Gamma Radiation Scanning Report (HGL and TPC, 2012b) and are maintained in Geographical Information Systems format. 3.3.4 Geophysical Survey A geophysical survey was performed at targeted locations identified in the Geophysical Investigation Plan (HGL, 2010c) for the Area IV Study Area. Targeted survey areas within each subarea were selected based on information summarized in the corresponding HSA TM (HGL, 2012a) and the aerial photographic analysis (USEPA, 2010). Areas suspected to have subsurface radioactivity with little or no surface indication were selected for geophysical measurements as well. For example, suspected subsurface process piping, leach fields, subsurface disposal areas, or trenches associated with past radiological activities were selected as target areas for geophysical survey. Targeted sample locations were identified from subsurface anomalies identified by the geophysical survey. A list of targeted soil sample locations was developed based on the results of the geophysical survey and was included in each subarea specific FSP Addendum. The results of the geophysical survey are presented in the Final Geophysical Investigation Report (HGL, 2011b). 3.4 SOIL AND SEDIMENT SAMPLING The primary objective of the soil and sediment sampling effort was to evaluate the nature of potential radiological contamination in soil and sediment within the Area IV Study Area that may have resulted from past nuclear operations and research activities that occurred at SSFL Area IV. Soil and sediment sampling activities were conducted in two rounds in accordance with the procedures outlined in the Final FSP for Soil Sampling (HGL, 2012d) and the Final Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-8 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California FSP for Groundwater Surface Water and Sediment (HGL, 2010d). Round 1 sampling activities included the collection of targeted soil and sediment samples and random surface soil samples. Round 2 sampling activities consisted of step-out sampling based on Round 1 analytical results that exceeded project established RTLs. A total of 3,487 environmental soil samples and 55 sediment samples, not including quality control field duplicates, were collected in the Area IV Study Area with 2,781 environmental samples collected during Round 1 and 761 environmental samples collected during Round 2. Additionally 193 duplicate samples were collected with 147 during Round 1 and 46 during Round 2. Table 3.1 summarizes the total number of soil samples collected and analyzed per subarea, the round it was collected, and the type of sample. The following subsections describe the logic used to identify Round 1 and Round 2 sampling locations. 3.4.1 Round 1 Soil and Sediment Sampling Round 1 targeted soil sampling locations were identified based on a combination of the findings and results from the HSA, aerial photograph interpretation study, gamma radiation survey, geophysical survey, and direct field observations. Targeted sediment sampling locations were based on the HSA, aerial photograph interpretation study, and direct field observations, because the gamma radiation and geophysical surveys had not been completed at the time Round 1 sediment samples were collected. The targeted sampling locations were presented in draft FSP addenda which were presented to the SSFL Technical Stakeholder Workgroup during regularly scheduled technical review meetings. Technical Stakeholder comments were incorporated into the FSP addenda when possible. During the technical review meetings, recommendations and action items including those on the topic of Likely Chemical Remediation Zones (LCRZ) and Likely Decontamination and Decommissioning Zone (LD&DZ) were discussed. Specific locations throughout the Area IV Study Area were designated as LCRZs by DOE and DTSC based on the concentrations of chemical analytes detected in samples collected as part of the Resource Conservation and Recovery Act investigation being conducted by DOE. Because the LCRZs will be remediated at a later date, only limited sampling was conducted by USEPA within the LCRZ boundaries. On occasion, a limited number of surface/subsurface samples were placed within the LCRZs and around the LCRZ perimeter to delineate more accurately the potential vertical and lateral extent of areas of interest. Likely Decontamination and Decommissioning Zones were defined as existing building complexes or existing concrete foundations of former buildings that will likely be considered for decontamination and decommissioning in the future. Soil samples were not collected within the LD&DZs because decontamination and decommissioning operations will remove infrastructure (building structures, concrete slabs, above-ground pipelines and underground pipelines etc.) and any impacted soil associated with the infrastructure. In accordance with the USEPA’s role under the AOC (DTSC, 2010) agreement between DTSC and DOE for the SSFL site, USEPA will conduct confirmation soil sampling to verify that site remediation goals have been achieved at all LCRZ and LD&DZs identified during the Area IV Radiological Study. These follow-on efforts are not included in the current scope of Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-9 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California work. It should be noted that if these LCRZ and LD&DZ are not remediated there will be an investigation data gap and these areas will not have been investigated for radiological contamination. After the locations were finalized with the Technical Stakeholder Workgroup, proposed sampling locations were marked in the field using a SPS 852 handheld Trimble GPS and magnetic survey spikes. Before sampling activities commenced, utility clearances were performed at each location by Underground Service Alert (Dig Alert) and a private utility locator. 3.4.1.1 Targeted Surface and Subsurface Soil Samples Surface soil samples were collected by first clearing the vegetation from the sampling location. Then a stainless steel trowel or shovel was used to collect the sample. The soil sample was collected from the first six inches of soil. Subsurface samples were collected using a Geoprobe 6600 Series direct-push technology unit or a hand auger. Continuous soil cores were collected for lithological description at each location. The boreholes were advanced to a depth of 10 feet below ground surface (bgs) or refusal. At specific targeted locations, borings were advanced to a greater depth. Depth intervals to be sampled were determined based on borehole gamma logging results. Soil associated with gamma radiation anomalies was sampled for laboratory analysis. If no gamma radiation anomalies were identified, a soil sample was collected at the upper portion of the boring (1 to 5 feet bgs). The soil within this interval was homogenized and a representative composite sample was collected for analysis. Due to the relatively low mobility of the radionuclides of interest, higher radionuclide concentrations were expected in the upper portion of the soil profile; collecting soil within the upper 5 feet increased the likelihood of detecting radiological contamination at a particular location. This approach for selecting soil sampling intervals was modified to target specific features that were identified through historical records (subsurface pipelines, leach fields, tanks, etc.). These modifications are described in the subarea specific FSP Addendum. Targeted deep borehole subsurface soil samples were also collected to characterize potential radiological contamination beneath four nuclear reactors; the deep concrete vaults at the Systems for Nuclear Auxiliary Power (SNAP), the Kinetic Experiment Water Boiler (KEWB), and the SRE, and the Shield Test and Irradiation Reactor (STIR) buildings. A roto-sonic drill rig was used to drill through concrete rubble that was placed back in the vault excavations after the reactor vaults had been removed. The findings of the Round 1 targeted sampling activities and the deep borehole investigation are discussed in individual TMs, which are located in Appendices A through J of this document. 3.4.1.2 Random Surface Sampling Random surface sample locations were identified within the NBZ in addition to the targeted soil samples. Cost savings incurred during earlier Round 1 sampling activities afforded an Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-10 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California allocation of 100 random surface samples for the NBZ to ensure more coverage of the subarea. Random sample locations were determined using the Create Random Point tool provided in ArcGIS software created by Environmental Systems Research Institute, Inc. In the event a random surface sample location was located on a rock outcrop, the location was moved to the nearest location from which a soil sample could be collected. If a sample location was inaccessible (due to physical constraints) an alternate random surface sampling location was chosen. Results of the random surface sampling are presented in the TM for the NBZ (Appendix I). 3.4.1.3 Sediment Sampling Potential Round 1 sediment locations were identified by evaluating the HSA findings, historical aerial photographs, and maps showing surface water drainage pathways. The potential sediment sampling locations were verified during a field reconnaissance which was conducted from October 6, 2010 to November 5, 2010. A total of 40 sediment sampling locations were identified during the reconnaissance. Detailed notes and photographs were taken at each location, as well as X-Y survey coordinates, which were recorded using a SPS 852 handheld Trimble GPS unit. Analytical results and RTL exceedances for the Round 1 sediment samples will be documented in the Surface Water and Sediment Sample Results Report. 3.4.2 Round 2 Soil and Sediment Sampling Round 1 soil analytical results were screened against project established RTLs to identify locations containing concentrations of radionuclides related to SSFL site operations that warranted further characterization. Round 2 sampling locations (step-out locations) were placed in the vicinity of Round 1 sample locations that where concentrations of radionuclides were detected above RTLs. A total of 761 step-out environmental samples were collected during Round 2 sampling activities. The process used to derive the RTLs and how they were used to determine Round 2 step-out sampling locations is summarized below. 3.4.2.1 Radiological Trigger Levels Analytical results from the Round 1 sampling were compared to the RTLs established specifically for the Area IV Study Area. RTLs were decision levels for the radionuclides of concern used as comparison concentrations for Round 1 analytical data in the absence of established clean up levels. The process used to derive the RTLs is presented in the RTL TM (HGL, 2011c), and is briefly summarized below. During the SSFL Radiological Background Study (HGL, 2011a), 149 soil samples were collected from off-site locations representing the two geological formations present at the SSFL Site. Based on the results of the Radiological Background Study, BTVs were developed for 64 radionuclides, which represent the upper limits of background concentrations. The rationale for the selection of the 64 BTVs between datasets that represent results across surface and subsurface soil, different geologic formations, separate reference locations, and datasets Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-11 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California with very low detection frequency (that is, single detections in a dataset) are summarized in the BTV and Radionuclide Selection Rationale paper (Appendix L). In some cases, the laboratory data used in the Area IV Study Area did not support the use of the BTVs in the decision-making process, due to practical or technological limitations in data quality. In those cases, where the laboratory minimum detectable concentration (MDC) for a given radionuclide was greater than the associated BTV, that MDC was used as the lowest practical alternative to the BTV. In addition, one radiochemistry laboratory, Pace Laboratories, was selected and contracted for the background study and two radiochemistry laboratories were contracted for the Radiological Study: TestAmerica Laboratories, Inc (TAL) and GEL Laboratories, LLC (GEL). Using three laboratories typically resulted in three different MDCs for each analysis. For consistency in evaluation of analytical results, when the MDC values differed between the laboratories, the higher concentration value was used to form the RTL. RTLs were only used to determine Round 2 step-out sampling locations, and included the method uncertainty from the analytical techniques. The RTL was based on the BTV (or the associated MDC, whichever was higher) plus a method uncertainty factor and was calculated based on a decision error rate of 5 percent, specified in the Final QAPP for Soil Sampling (HGL, 2012e). A laboratory result that exceeded the RTL indicated that, at the specified confidence interval, the sample was likely to have exceeded the BTV (or MDC). As described in the RRC paper, Appendix K, a calculation error in the RTLs was discovered after the soil and sediment results were reported and verified (and after the analytical results were presented and discussed with the stakeholders). Therefore, to be consistent with all Round 1 TMs and discussions with technical stakeholders, the data presented in all the Round 1 TMs was compared to original RTLs. The analytical results themselves are unaffected by the RTL error and no additional locations are found based on corrected screening levels. Radiological trigger levels exceedances identified during Round 1 soil sampling activities are discussed in the TMs for each subarea (Appendices A through J). After sample results had been validated, an evaluation of all laboratory results was conducted to provide the most defensible and technically sound advice to project stakeholders, in particular the DTSC regarding the procurement of future laboratory services. Thus, RRCs were developed from the entire dataset of soil and sediment sample analytical results. These RRCs were developed in a similar methodology as the RTLs but with enhancements. The development, appropriate uses, and limitations of the RRCs and the associated calculation parameters are detailed in Appendix K. 3.4.2.2 Surface and Subsurface Soil Step-out Sampling Locations Step-out locations were identified in areas where additional data was required to fully characterize soil adjacent to a Round 1 soil sample that had concentrations exceeding RTLs. Each location was field verified and drainage patterns, topography, and locations of structural drainage from buildings were considered to characterize potential transport of elevated radionuclide results. Step-out locations were approximately 10 to 40 feet away from their respective Round 1 sample location. Generally four step-out sampling locations were placed Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-12 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California around each Round 1 exceedance at 90 degree azimuth intervals where data was needed. Some locations exhibiting Round 1 exceedances required no step-out samples as they were within LRCZs, or were well delineated by neighboring Round 1 sample locations, so fewer than four Round 2 samples were needed. The RTL exceedances and rationale used to place Round 2 step-out locations are documented in each subarea specific FSP addendum. Analytical results of soil samples collected during Round 1 and Round 2 sampling are presented in the subarea specific TMs presented in Appendices A through J. Round 2 samples were not collected within Subarea 3 as no Round 1 samples exhibited radionuclide concentrations above the RTLs. Additionally, Round 2 samples were not collected within the NBZ, as this activity was not within the scope of this project. Further recommended characterization activities are discussed in Section 4.0 by subarea. 3.4.2.3 Sediment Step-out Locations Analytical results of 40 sediment samples collected during Round 1 showed two samples containing radionuclide concentrations that exceeded RTLs. One sample was located down gradient of Outfall 3, east of the SRE and one sample was located down gradient of Outfall 4, northwest of the RMHF. Step-out sediment samples were placed within the drainage upgradient and downgradient of each Round 1 RTL exceedances location. A total of 55 stepout samples were collected during the Round 2 sediment sampling event. Analytical results for the Round 2 sediment samples are documented in the Surface Water and Sediment Sample Results Report. 3.5 QUALITY ASSURANCE/QUALITY CONTROL The QA and QC program implemented during soil sampling and analysis efforts ensured that equipment and instruments functioned properly and the data collection process was performed consistently with project requirements. The QA program ensured that all data collection procedures and measurements were scientifically sound; were of known, acceptable, and documented quality; and were conducted in accordance with the requirements of the project as discussed in the Final FSP for Soil Sampling (HGL, 2012d) and the Final QAPP for Soil Sampling (HGL 2012e). Systematic monitoring of QA processes reduced occurrences of errors during soil collection and analysis. The QC program focused on testing procedures to verify field methods and laboratory detection systems were functioning correctly and fully operational before data collection commenced, and to ensure collected data were consistent, comparable, accurate, and within specified limits of precision. Before submission of field samples to the two laboratories, a single-blind performance evaluation was conducted. This evaluation assessed the ability of TAL and GEL to generate results within acceptable limits of analytical accuracy and precision. The single-blind samples were of known concentrations to the manufacturer and HGL but unknown to the laboratories. Performance evaluation sample results were evaluated against the certified values provided by the manufacturer. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-13 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California 3.5.1 Laboratory Quality Control Elements Laboratory QC samples included calibration verification checks, method blanks, laboratory control samples, carrier and tracer performance, matrix spike analyses, and laboratory duplicates as required by each analytical method. These QC elements were specific to each analytical method and are described in general terms in the selected project laboratory QA manual in Appendix A of the Final QAPP for Soil Sampling (HGL, 2012e) and in more detail in method-specific standard operating procedures. The laboratory QC elements were based on descriptions presented in the Multi-Agency Radiological Laboratory Analytical Protocols (MARLAP) (USEPA, 2004). The acceptance criteria, corrective action, and evaluation protocols associated with these QC elements are presented in Table 3.3 of the Final QAPP for Soil Sampling (HGL, 2012e). Laboratoryspecific information on technical approaches to comply with the QC element requirements of this section are presented in the laboratory-specific QAPP addenda (HGL, 2012e). Results of the QC tests were included in the analytical data packages and used during the data validation process to determine data usability. 3.5.2 Quality Control Samples Field QC samples were collected to gauge the accuracy and precision of field collection and laboratory analytical activities and to assess data usability. QC samples collected in the field and submitted to the laboratory for analysis included field duplicates, equipment rinsates, and decontamination source water blanks. Each subarea specific FSP addendum provided specific information on the number and types of analyses to be performed. Requirements for QC samples were specified in the Final FSP for Soil Sampling (HGL, 2012d) and the Final QAPP for Soil Sampling (HGL, 2012e) and are also summarized in the following subsections. 3.5.2.1 Field Duplicates Field duplicate samples were collected at a rate of 1 per 20 (5 percent) environmental samples collected. Soil field duplicates were obtained using co-located samples rather than the conventional homogenized and split samples. This method resulted in the collection of representative samples that better suited the project requirements. Surface soil duplicate samples were collected within 2 feet of the location of the parent sample. Subsurface soil duplicate samples were collected from borings offset slightly from the boring advanced to collect the parent sample. Field duplicate samples were submitted to the laboratory as blind QC samples (with unique sample identifiers) to ensure that they were analyzed in the same manner as all other environmental samples. Field duplicate results were used to estimate of overall precision of sample collection, field sample preparation, site homogeneity, and laboratory analysis (total measurement of sample variability). 3.5.2.2 Equipment Rinsate and Source Water Blanks Equipment rinsate blank samples were collected to ensure proper decontamination of nondedicated sampling equipment. One equipment rinsate blank was collected for each type of Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-14 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California sampling equipment per field team per day. Following decontamination, the blank was collected by pouring ASTM Type II water (also called organic free water) through or over the equipment and collecting the rinse water in the appropriate container. Each equipment blank sample was analyzed for uranium isotopes and H-3 (on a sample-dependent basis). A sample of the ASTM Type II decontamination source water used for the equipment decontamination and rinsate blank was collected and analyzed for uranium isotopes and H-3. The decontamination source water blank samples were collected each time a new lot of source water was received. The source water samples were used to document existing radionuclide concentrations in the water. The results of the source water blanks were compared to the equipment rinsate blanks to aid in determining the effectiveness of decontamination procedures. These comparisons are discussed in the TM for each subarea (Appendices A through J). 3.5.3 Data Validation Data validation ensured that laboratory analytical results met the objectives of the project as documented in the Final QAPP for Soil Sampling (HGL, 2012e). Data validation compared the final dataset against a set of criteria as detailed in the QAPP to ensure the data were usable. Analytical data packages were received from the laboratories in electronic data deliverable (EDD) formats for uploading into the project database. Data verification and validation services were subcontracted to third parties, The Palladino Company, Inc. (TPC) and Validata Chemical Services, Inc. (Validata), in order to maintain maximum transparency of data quality. A quality check of the laboratory results was performed by reviewing sample numbers against chain-of-custody forms and field sheets for consistency and completeness. Qualifiers were reviewed and added by the validator to determine usability of results. Data validation was performed in accordance with the DOE guidance documents: Evaluation of Radiochemical Data Usability (DOE, 1997) and MARLAP (USEPA, 2004). Each data validator was a radiochemist with at least two years of experience in radiochemical separations and measurement and did not have any perceived or actual conflict of interest with the laboratory generating data, such as recent prior employment by the same laboratory. Table 3.3 of the Final QAPP for Soil Sampling (HGL, 2012e) shows data qualification conventions for QC elements associated with the project analyses. These conventions are general, and were supplemented by method-specific QC elements where appropriate. When analytical results were reported in association with QC results that did not meet the performance criteria, the validator applied the appropriate qualifier. Alternative qualification approaches that contradicted the requirements of Table 3.3 were allowed if, in the validator’s judgment, the alternative was appropriate for a specific QC issue. Each instance of application of an alternative protocol was documented in the corresponding data validation report to allow for USEPA review and final approval. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-15 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California 3.5.3.1 Data Validation Methods Laboratory analytical data packages were validated using a two-tiered approach. Tier 1 required Level IV data validation for 100 percent of data packages. Tier 2 required Level IV data validation for 25 percent of data packages and Level II data validation for 75 percent of data packages. The choice of validation tier was based on the ability of the laboratory to provide data of acceptable quality. A data package was unacceptable if any portion of its contents were considered non-defensible, could not be validated due to insufficient supporting documentation, or data was returned by HGL to the laboratory for repair. These criteria were applied to 10 consecutive data packages for analytical method for each laboratory. Tier 1 data validation was performed for the first 10 consecutive data packages for a specific analytical method. If nine or more data packages met the quality criteria then Tier 2 data validation was performed. If more than one data package did not meet the quality criteria then Tier 1 data validation was continued until nine of ten consecutive data packages for the specific analytical method passed the criteria. Tier 2 data validation was conducted as long as nine of 10 consecutive data packages met the quality criterion; else Tier 1 data validation was resumed. Due to data package discrepancies and deficiencies all TAL data packages were validated using Tier 1, Level IV validation. GEL data packages were initially validated using Tier 1 then for Round 2 soil samples went to Tier 2 to expedite the data throughput. Level IV and Level II validation requirements are discussed in detail in the Final QAPP for Soil Sampling (HGL, 2012e). Level IV validation required a more in-depth and thorough review of the analytical data package than Level II. Both validation levels consisted of verification and validation checks for the compliance of sample receipt, sample characteristics, and analytical results. Additionally, results were checked for transcription errors from raw data to summary forms and calculation verifications were performed for selected samples. 3.5.4 Evaluation of Split Samples Six soil samples were analyzed by both TAL and GEL for the purpose of evaluating the comparability of the analytical methodologies between the two laboratories (HGL, 2012f). In order to ensure that representative “split sample” fractions were analyzed, each laboratory sent the other laboratory archived sample fractions from three individual samples that were dried, ground, and appropriately sub-sampled, per the instructions and procedures described in the analytical scope of work and the Final QAPP for Soil Sampling (HGL, 2012e). Sample selection was based on a subjective review of reported results from each laboratory. One sample was selected based on each of the following criteria: • A high bias resulting in reported values above the critical level (Lc) and/or MDC (that is, potentially false positive). Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-16 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California • • A low bias resulting in reported values below the Lc and/or MDC (that is, potentially false negative). A reported result representing the upper limit of observed results for one or more analytes (that is, highest concentration). The split samples were analyzed using the four primary analytical methods: gamma spectrometry; alpha spectrometry; gas proportional counting; and liquid scintillation counting. The laboratories submitted Level IV data packages for the split sample analyses, in accordance with the analytical subcontract. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3-17 HydroGeoLogic, Inc. 12/21/2012 This page was intentionally left blank. HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California 4.0 ROUND 1 AND ROUND 2 ANALYTICAL RESULTS This section presents the radiological analytical results for the Round 1 and Round 2 soil and drainage/sediment sampling performed in the Area IV Study Area. As described in Section 3.4.2.1 the RTLs were developed and used as field decision levels in the absence of established clean up levels to determine where Round 2 step-out samples should be located. As noted above, the RTLs (applied to select Round 2 sample locations) included both method uncertainty and the maximum of two project radiochemistry MDC values, hence they are not the most conservative values with which to present study results. These RTLs are not used in the final evaluation of the radiological data. Currently, Look-up Table values for radionuclides have not been established. These values will be established by DTSC in accordance with the AOC which states that the Look-up Table will “include both background concentrations as well as minimum detection limits for specific contaminants whose minimum detection limits exceed local background concentrations.” (DTSC, 2010) To satisfy this AOC requirement the final radiological data have been compared to Field Action Levels (FAL) consisting of either the BTVs or the 2σ UCL MDCs, as applicable. The FAL is lower than the RTL or RRC values because they do not consider the method uncertainty as described above. Because DTSC has not yet established Look-up Table values, all analytical results from USEPA’s radiological study exceeding the FAL are presented. The final Look-up Table Values depend on the level of data quality performance to be contracted by DTSC. The FALs (being action levels) are a conservative way to present the radiological study data, i.e., FAL are the lowest values which with to compare soil and sediment results. USEPA provided recommendations for the development of Look-up Table Values in a technical memorandum (HGL, 2012g). Sample results exceeding the FAL do not necessarily represent locations of contamination. In accordance with the AOC, DTSC will determine Look-up Table values for comparison to all sample results to determine locations of contamination that warrant remediation. Results that exceed USEPA’s FAL are potential locations that may require further investigation and/or remediation dependent upon the Look-up Table values. However, these results do not represent areas of contamination or areas of remediation The following subsections describe the development of FALs in more detail, the results of the data quality evaluation, and summarize the Round 1 and Round 2 analytical results. 4.1 DATA QUALITY EVALUATION The quality of the analytical data and the applicability of that data for its intended use has been evaluated against the data quality objectives (DQO) and measurement quality objectives (MQO) described in the Final QAPP for Soil Sampling (HGL, 2012e) including applicable revisions and addenda. These DQOs and MQOs include routine criteria such as spike recovery, method blank activity and duplicate precision, as well as non-routine, project- Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-1 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California specific criteria such as the required method uncertainty and the use of explicitly defined detection limit calculations. Field sample data have been thoroughly reviewed, verified, and validated to ensure that any data used to evaluate the nature of areas of interest in the Area IV Study Area either meet the stated DQOs and MQOs described in the Final QAPP for Soil Sampling or was explicitly qualified to describe any limitations impacting the use of the data. Field sample data that was determined to be unsuitable for its intended purpose has been rejected and removed from consideration. Wherever feasible, rejected data was returned to the laboratory, the affected samples were reanalyzed, and the data was either repaired or replaced. Technical review of field sample results, as well as the field QC sample results discussed below, suggests that in some cases the laboratories’ reported uncertainty values, which accompany the sample activity results, may be slightly underestimated. Such an underestimate of the reported uncertainty is considered conservative, as no data is believed to be accepted when it should have been rejected. This small underestimate of the reported uncertainty values appears to be generally associated with very low-level gamma spectrometry and alpha spectrometry results. As those results tend to be well below the levels of concern for this project, the overall data quality is not believed to be significantly affected and the data is acceptable for its intended use. The quality and integrity of the field sample data was further evaluated by the laboratory analysis of 1,002 field sampling equipment blanks and associated source water samples. The evaluation of equipment blank results indicated that the decontamination of the field sampling equipment was effective and that there was no evidence of sample cross-contamination from the sampling equipment that could have adversely affected the quality or usability of the reported field sample data. Heterogeneity in the field, i.e. variability in the concentration of the various analytes of interest over relatively small areas, was evaluated by the analysis field duplicate samples. The evaluation of 12,442 results (individual radionuclides from all analyses) from 195 field sample/duplicate pairs suggested (a) a degree of heterogeneity in field sampling locations slightly higher than the 10 percent initially assumed in the development of field duplicate acceptance criteria, and (b) generally supports the assessment of a small underestimate in the laboratories’ reported uncertainty values for certain analyses. Neither the degree of heterogeneity observed in the field duplicate sampling locations, nor the potential underestimate of the reported uncertainty was believed to significantly impact the usability of the data. The evaluation of the split samples for inter-laboratory comparability of radioanalytical results was found to be acceptable (HGL 2012f). Minor concerns were noted regarding the laboratories’ reported uncertainties and the observed exceedance rate for the ZDUP evaluation criteria. The underestimate of analytical uncertainty does not raise significant concerns regarding the use of the data for its intended purpose. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-2 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Overall, the data were usable for their intended purpose, which was to evaluate the nature and extent of areas of interest within the Area IV Study Area that may have resulted from past nuclear research activities within SSFL Area IV. 4.2 FIELD ACTION LEVELS Soil and drainage sediment sample analytical results, both surface and subsurface, were compared to FALs (Table 4.1). Sample locations with results equal to or greater than the FAL were considered locations of interest, and are illustrated on Figures 4.1 through 4.15 and are discussed in Section 4.3 The FALs were derived from the Radiological Background Study BTVs and from the Area IV Radiological Study 2 sigma (2σ) (97.7 percent confidence level of the standard normal cumulative probability) upper confidence limit (UCL) MDCs as described in this section. The 2σ UCL MDCs were calculated from 3,772 sample results, which represent all solid matrix samples collected and analyzed during the Area IV Radiological Study. These MDCs are empirical reported MDCs obtained by each laboratory. The sample analytical results were compiled for each radionuclide for each laboratory. The datasets for each radionuclide ranged from 5 to 2,464 samples. For each radionuclide and each laboratory, the mean MDC and the standard deviation of the mean MDC were calculated. The mean MDC was summed with twice the standard deviation or sigma to determine the UCL for the respective MDC dataset as follows: 2σ UCL MDC = mean MDC + (2*standard deviation of mean MDC) The greater of the BTV or 2σ UCL MDC was selected as the FAL for each laboratory for each radionuclide. Table 4.1 summarizes the FALs. Sample results were compared to the FALs and results equal to or greater than the FAL were identified as potential Radiological Areas of Interest. To provide enhanced visual analysis of sample data on the figures, results were categorized into five data ranges as follows: • • • • • 4.3 Less than the FAL, Equal to or greater than the FAL and less than twice the FAL, Equal to or greater than twice the FAL and less than thrice the FAL, Equal to or greater than thrice the FAL and less than four times the FAL, Equal to or greater than four times the FAL. RADIONUCLIDES EXCEEDING FIELD ACTION LEVELS Of the 55 radionuclides analyzed, 28 were detected above the FALs in surface and subsurface soils from the Area IV Study Area (Table 4.1). Of these 17 were identified as NORM. The background study demonstrated that NORM radionuclides are present in unimpacted areas with a degree of variability in concentrations. It is possible that a radionuclide or several radionuclides could exceed FALs but would not be due to SSFL radiological operations. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-3 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California The remaining 11 radionuclides exceeding the FALs can be attributed to SSFL radiological operations, and are referred to as site-related radionuclides: Am-241, Cs-137, Co-60, Cm243/244, europium (Eu)-152, Eu-154, Ni-59, Pu-238, Pu-239/240, Sr-90 and H-3. These results are presented in Tables 4.2 and 4.3 and Figures 4.1 through 4.15. The following subsections discuss the radionuclides detected above FALs frequency of occurrence. The locations are described relative to various features (building, drainage, etc.) within the Area IV Study Area. For simplicity, the feature is described first with the distance and direction of sample locations described second. For example, Subarea 5A describes five Cs-137 sample results that exceeded the FAL, which were located approximately 60 feet west of the Former Building 4064 drainage. Thus, the text is written as “Former Building 4064 drainage, approximately 60 feet west (5 samples).” This allows the reader to focus on the feature, then the distance and direction from the feature to the sample location(s), and finally, the number of samples associated with the feature. 4.3.1 Cesium-137 The FAL for Cs-137 is the BTV of 0.193 picocuries per gram (pCi/g). Cesium-137 was detected in 291 soil samples at concentrations greater than the FAL, ranging from 0.194 to 196 pCi/g. Cesium-137 was part of the default analyte suite; therefore, all Round 1 soil samples were analyzed for Cs-137 during and only select soil samples were analyzed for Cs137 during the Round 2 soil sampling event. With the exception of Subarea 3, Cs-137 was detected in every subarea and the NBZ. These concentrations are presented by subarea (surface and subsurface) in Tables 4.2 and 4.3 and are illustrated on Figures 4.1 and 4.2. Details pertaining to each subarea regarding the distribution of Cs-137 are provided in the following subsections. Subarea 5A In this subarea, 164 surface soil and 227 subsurface soil samples were collected for Cs-137 analysis. Eight surface soil samples contained Cs-137 at concentrations exceeding the FAL, ranging between 0.2 and 0.993 pCi/g. These samples are located in three areas: • • • Former Fuel Element Storage Facility Building 4064 drainage, approximately 60 feet west (5 surface soil samples). Seven additional samples associated with this Key Facility will be discussed in the Subarea 6 section. Heavy Metals Likely Chemical Remediation Zone Area, located in the southwest corner of Subarea 5A (2 surface soil samples) Storm water channel south of G Street and northwest of Building 4029 (1 surface soil sample) Cesium-137 was not detected at concentrations exceeding the FAL in subsurface soil samples collected from Subarea 5A. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-4 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Subarea 5B In this subarea, 245 surface soil and 281 subsurface soil samples were collected for Cs-137 analysis. Fourteen surface soil samples contained Cs-137 at concentrations exceeding the FAL ranging from 0.213 to 0.911 pCi/g. These samples were collected from two areas: • • 17th Street Drainage Area (12 surface soil samples) Former Building 4010 Area (2 surface soil samples; note that one sample is geographically located in Subarea 7 but is associated with the Former Building 4010 Area) Cesium-137 was not detected at concentrations exceeding the FAL in subsurface soil samples collected from Subarea 5B. Subarea 5C In this subarea, 90 surface soil and 129 subsurface soil samples were collected for Cs-137 analysis. Two surface soil samples contained Cs-137 at concentrations exceeding the FAL at 0.316 and 0.818 pCi/g. These samples were collected from one area: • Building 4100 Area (Fast Critical Experiment), 15 feet northeast (2 surface samples) Cesium-137 was not detected at concentrations exceeding the FAL in subsurface soil samples collected from Subarea 5C. Subarea 5D In this subarea, 293 surface soil and 303 subsurface soil samples were collected for Cs-137 analysis. Eight surface soil samples contained Cs-137 at concentrations that exceeded the FAL ranging from 0.194 to 1.42 pCi/g. These samples were collected from three areas: • • • The portion of 5D-South (6 surface soils samples) Former Building 4020 (Hot Lab), approximately 100 feet northwest (1 surface soil sample) Isolated location approximately 150 feet northwest of former Building 4353 (1 surface soil sample) Cesium-137 was not detected at concentrations exceeding the FAL in subsurface soil samples collected from Subareas 5D-North and 5D-South. Subarea 6 In this subarea, 297 surface soil and 345 subsurface soil samples were collected for Cs-137 analysis. Eighty-two surface and 11 subsurface soil samples contained Cs-137 at concentrations exceeding the FAL ranging from 0.194 to 196 pCi/g. These samples were collected from eight areas: • SRE Complex (21 surface and 2 subsurface soil samples) Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-5 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California • • • • • • • Liquid and Gas Radioactive Storage Tanks Area, located on the north side of the SRE Complex (22 surface and 3 subsurface soil samples) SRE Pond and Drainage (5 surface and 4 subsurface soil samples) Hot Oil Sodium Cleaning Facility (8 surface soil samples) Former Fuel Element Storage Building 4064 Drainage, in the drainage way leading to the east towards the New Conservation Yard. It should be noted that this area, along the southern side of G Street, is where the highest concentration of Cs-137 was detected during the investigation at a level of 196 pCi/g (8 surface and 1 subsurface soil samples) Old Conservation Yard (2 surface and 1 subsurface soil samples) New Conservation Yard (12 surface soil samples) Former Building 4003 – Engineering Test Building (4 surface soil samples) Subarea 7 In this subarea, 216 surface soil and 208 subsurface soil samples were collected for Cs-137 analysis. One hundred and thirty surface and 24 subsurface soil samples contained Cs-137 at concentrations exceeding the FAL ranging from 0.195 to 20.2 pCi/g. These samples were collected from six different areas: • • • • • • RMHF fence line (34 surface and 9 subsurface soil samples) Site 4614 RMHF Holding/Catchment Basin (25 surface and 3 subsurface soil samples) RMHF Leach Field located approximately 100 feet north of the RMHF in the northern drainage (27 surface and 8 subsurface soil samples) Hazardous Waste Management Facility and adjacent debris field (26 surface soil samples) Interim Storage Facility (7 surface and 4 subsurface soil samples) Panhandle Area (11 surface soil samples; note one sample is geographically located in the NBZ West but is associated with this feature) Subarea 8 In this subarea, 209 surface soil and 188 subsurface soil samples were collected for Cs-137 analysis. Eight surface soil samples contained Cs-137 at concentrations exceeding the FAL ranging from 0.197 to 0.878 pCi/g. These samples were collected from four different areas: • • • • Subarea 8-South, two clusters near the western boundary (4 surface samples) Former Sodium Disposal Facility (2 surface soil sample) Former Building 4056 Landfill (1 surface soil sample) Former Empire State Atomic Development Authority Area (1 surface soil sample) Cesium 137 was not detected at concentrations exceeding the FAL in subsurface soil samples collected from Subareas 8. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-6 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Northern Buffer Zone In the NBZ, 160 surface soil and 73 subsurface soil samples were collected for Cs-137 analysis. Three surface soil samples contained Cs-137 at concentrations exceeding the FAL ranging fom 0.207 to 0.277 pCi/g. These samples were collected from the following two areas: • • NBZ West (1 surface soil samples) NBZ East (2 surface soil samples) Cesium-137 was not detected at concentrations exceeding the FAL in subsurface soil samples collected from the NBZ. 4.3.2 Strontium-90 The FALs for Sr-90 are the MDC 2σ UCL of 0.387 pCi/g for GEL data and the BTV of 0.0750 pCi/g for TAL data. Strontium-90 was part of the default analyte suite; therefore, all Round 1 soil samples were analyzed for Sr-90 and only select locations were analyzed for Sr90 during the Round 2 soil sampling event. Strontium-90 was detected in 153 soil samples at concentrations above the FALs, ranging from 0.01 to 21.3 pCi/g. Strontium-90 was detected throughout the entire Area IV Study Area. These concentrations are presented by subarea (surface and subsurface) in Tables 4.2 and 4.3 and are illustrated on Figures 4.3 and 4.4. Details pertaining to each subarea regarding the distribution of Sr-90 are provided in the following subsections. Subarea 3 In this subarea, 2 surface soil and 11 subsurface soil samples were collected for Sr-90 analysis. One subsurface soil sample contained Sr-90 exceeding the FAL at a concentration of 0.444 pCi/g. This single sample was located on the south side of the Southern California Edison Substation. Strontium-90 was not detected at concentrations exceeding the FAL in any of the surface soil samples collected from Subarea 3. Subarea 5A In this subarea, 144 surface soil and 206 subsurface soil samples were collected for Sr-90 analysis. One surface and two subsurface soil samples contained Sr-90 exceeding the FAL at concentrations ranging from 0.091 to 2.56 pCi/g. These samples were collected from two areas: • • Former KEWB Reactor Facility (1 surface soil sample) Former Building 4093, L85 Nuclear Experimentation Reactor (2 subsurface soil samples) Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-7 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Subarea 5B In this subarea, 225 surface soil and 261 subsurface soil samples were collected for Sr-90 analysis. Three surface and two subsurface soil samples contained Sr-90 at concentrations exceeding the FALs ranging from 0.090 to 0.563 pCi/g. These samples were collected from five areas: • • • • • Building 4011 area, southwest of Building 4011 (1 subsurface soil sample) Building 4019 area, north of Building 4019 (1 subsurface soil sample) Former Building 4010, SNAP Reactor (1 surface soil sample) Building 4006, approximately 100 feet southeast (1 surface soil sample) Building 4006, approximately 100 feet west in footprint of former Building 4026 (1 surface soil sample) Subarea 5C In this subarea, 81 surface soil and 119 subsurface soil samples were collected for Sr-90 analysis. One surface soil sample contained Sr-90 at a concentration of 0.098 pCi/g that exceeded the FAL. This single sample was located in an open area approximately 300 feet southwest of Building 4462, between 22nd and 23rd streets. Strontium-90 was not detected at concentrations exceeding the FAL in any of the subsurface soil samples collected from Subarea 5C. Subarea 5D In this subarea, 274 surface soil and 288 subsurface soil samples were collected for Sr-90 analysis. Fifteen surface and 13 subsurface soil samples contained Sr-90 at concentrations exceeding the FALs ranging from 0.395 to 1.55 pCi/g. These samples were collected from the following ten areas: • • • • • • • • • • Former Hot Lab Area, former Building 4020 (6 surface and 8 subsurface soil samples) Building 4009, in the south ditch along G Street, east of Building 4009 (1 surface soil sample) Building 4055 Former Liquid Waste Holdup System (1 surface soil sample) Former Building 4373 Leach Field (1 surface soil sample) Former Building 4353 Area, in the ponded area approximately 250 feet southeast of Former Building 4353 (3 surface soil samples) Former Building 4875 Area (1 surface and 1 subsurface soil samples) Former Building 4375 footprint (1 subsurface soil sample) Former Buildings 4173/4865 (1 surface soil sample) Pond Dredge Area (1 subsurface soil sample) Subarea 5D-South (1 surface and 2 subsurface soil sample) Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-8 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Subarea 6 In this subarea, 211 surface soil and 259 subsurface soil samples were collected for Sr-90 analysis. Eleven surface and 5 subsurface soil samples contained Sr-90 at concentrations exceeding the FALs ranging from 0.185 to 21.3 pCi/g. These samples were collected from the following four areas: • • • • SRE Complex (3 surface and 1 subsurface soil samples) Liquid and Gas Radioactive Storage Tanks Area (5 surface and 1 subsurface soil samples). SRE Pond and Drainage (2 surface and 2 subsurface soil samples) Fuel Element Storage Facility, in the drainage way leading to the east, towards the New Conservation Yard (1 surface and 1 subsurface soil sample) Subarea 7 In this subarea, 169 surface soil and 187 subsurface soil samples were collected for Sr-90 analysis. Thirty-three surface and 28 subsurface soil samples contained Sr-90 at concentrations exceeding the FALs ranging from 0.392 to 14.3 pCi/g. These samples were collected from the following nine areas: • • • • • • • • • RMHF fence line (5 surface and 1 subsurface soil samples) Site 4614 RMHF Holdup Pond/Catch Basin (1 surface and 7 subsurface soil samples) RMHF Leach Field and northern drainage (16 surface and 11 subsurface soil samples) Hazardous Waste Management Facility and adjacent debris field (1 surface soil sample) Interim Storage Facility (4 surface and 3 subsurface soil samples) Subarea 7 Northern Panhandle Area (6 surface and 1 subsurface soil samples) Southwestern corner of Subarea 7, approximately 200 feet northwest Building 4019 (2 subsurface soils samples) STIR Facility (2 subsurface soil sample) Outfall 3 (1 subsurface soil sample) Subarea 8 In this subarea, 190 surface soil and 172 subsurface soil samples were collected for Sr-90 analysis. Fourteen surface and 13 subsurface soil samples contained Sr-90 at concentrations exceeding the FALs ranging from 0.4 to 2.71 pCi/g. These samples were collected from the following five areas: Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-9 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California • • • • • Building 4009 area (1 surface and 1 subsurface soil samples) Building 4009 Leach Field area (2 surface and 1 subsurface soil sample) Sodium Disposal Facility (1 surface and 2 subsurface soil samples) Former Empire State Atomic Development Authority Facility (6 surface and 5 subsurface soil samples) Subarea 8-South (4 surface and 3 subsurface soil samples) Northern Buffer Zone In the NBZ, 160 surface soil and 73 subsurface soil samples were collected for Sr-90 analysis. Nine surface and 2 subsurface soil samples contained Sr-90 at concentrations exceeding the FALs ranging from 0.075 to 0.978 pCi/g. These samples were collected from the following four areas: • • • • • 4.3.3 NBZ NBZ NBZ NBZ NBZ West Subarea 8 drainages (5 surface and 1 subsurface soil samples) West RMHF drainages (3 surface soil samples) West northern area (1 subsurface soil sample) West, drainage from former Sodium Disposal Facility (1 subsurface soil sample) East SRE drainage (1 surface soil samples) Plutonium-239/240 The FALs for Pu-239/240 are the MDC 2σ UCL of 0.0369 pCi/g for GEL data and the BTV of 0.0142 pCi/g for TAL data. Plutonium-239/240 was part of the default analyte suite, therefore, all Round 1 soil samples were analyzed for Pu-239/240; however, only select locations were analyzed for Pu-239/240 during the Round 2 soil sampling event. Plutonium-239/240 was detected in 14 soil samples at concentrations greater than the FAL, ranging from 0.0233 to 0.187 pCi/g. Plutonium-239/240 was detected in soil samples collected from Subareas 5C, 5D, 6, 7, 8 and the NBZ. These concentrations are presented by subarea (surface and subsurface) in Tables 4.2 and 4.3 and are illustrated on Figures 4.5 and 4.6. Details pertaining to each subarea regarding the distribution of Pu-239/240 are provided in the following subsections. Subarea 5C In this subarea, 20 surface soil and 124 subsurface soil samples were collected for Pu-239/240 analysis. Two surface soil samples contained Pu-239/240 at concentrations exceeding the FALs at 0.0233 and 0.0487 pCi/g. These two samples were collected from the following two areas: • • Building 4100, approximately 70 feet northwest of Building 4100 (1 surface soil sample) Building 4015, approximately 350 feet southeast, along the southern border (1 surface soil sample) Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-10 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Plutonium-239/240 was not detected at concentrations exceeding the FALs in any of the subsurface soil samples collected from Subarea 5C. Subarea 5D In this subarea, 235 surface soil and 248 subsurface soil samples were collected for Pu239/240 analysis. One surface and 1 subsurface soil sample contained Pu-239/240 at concentrations of 0.0502 and 0.0526 pCi/g above the FALs. These two samples were collected from the following two areas: • • Former Building 4353, in the ditch on the south side of I Street and approximately 60 feet south of Building 4353 (1 subsurface soil sample) Southern portion of 5D-South (1 surface soil sample) Subarea 6 In this subarea, 194 surface soil and 247 subsurface soil samples were collected for Pu239/240 analysis. Three surface soil samples contained Pu-239/240 at concentrations exceeding the FAL with concentrations of 0.0302, 0.038 and 0.0515 pCi/g. These samples were collected from the following three areas: • • • SRE Complex, northwest corner of the complex (1 surface soil sample) SRE Pond and Drainage (1 surface soil sample) Hot Oil Sodium Cleaning Facility (1 surface soil sample) Plutonium-239/240 was not detected at concentrations exceeding the FALs in any of the subsurface soil samples collected from Subarea 6. Subarea 7 In this subarea, 129 surface soil and 138 subsurface soil samples were collected for Pu239/240 analysis. Three surface and 1 subsurface soil samples contained Pu-239/240 at concentrations of exceeding the FALs ranging from 0.0323 to 0.187 pCi/g. These samples were collected from the following four areas: • • • • RMHF, western fence line (1 surface soil sample) Site 4614 RMHF Holdup Pond/Catchment Basin (1 surface soil sample) Outfall 3, north of the RMHF (1 surface soil sample) STIR (1 subsurface soil sample) Subarea 8 In this subarea, 152 surface soil and 131 subsurface soil samples were collected for Pu239/240 analysis. Two subsurface soil samples contained Pu-239/240 at concentrations of 0.0713 and 0.0873 pCi/g exceeding the FALs. These samples were collected from the following two areas: Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-11 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California • • Former Sodium Disposal Facility (1 subsurface soil sample) 4056 Landfill (1 subsurface soil sample) Plutonium-239/240 was not detected at concentrations exceeding the FAL in any of the surface soil samples collected from Subarea 8. Northern Buffer Zone In the NBZ, 160 surface soil and 73 subsurface soil samples were collected for Pu-239/240 analysis. One surface soil sample contained Pu-239/240 at a concentration of 0.0384 pCi/g, exceeding the FAL. This sample was located approximately 250 feet north and upgradient of the RMHF Leach Field. Plutonium-239/240 was not detected at concentrations exceeding the FAL in any of the subsurface soil samples collected from the NBZ. 4.3.4 Cobalt-60 The FALs for Co-60 are the MDC 2σ UCL of 0.0252 pCi/g for GEL data and 0.0228 for TAL data. Cobalt-60 was part of the default analyte suite, therefore all soil samples were analyzed for Co-60 during the Round 1 soil sampling event and only select locations were analyzed for Co-60 during the Round 2 soil sampling event. Cobalt-60 was detected in four soil samples at concentrations greater than the FALs, ranging from 0.0228 to 0.048 pCi/g. The four samples were collected from Subareas 5B, 5C, 6 and 7, no other subareas or the NBZ contained samples with concentrations above the FAL for Co60. These concentrations are presented by subarea (surface and subsurface) in Tables 4.2 and 4.3 and are illustrated on Figures 4.7 and 4.8. Details pertaining to each subarea regarding the distribution of Co-60 are provided in the following subsections. Subarea 5B In this subarea, 225 surface soil and 275 subsurface soil samples were collected for Co-60 analysis. One subsurface sample contained Co-60 at a concentration of 0.228 pCi/g exceeding the FAL. This sample was collected northwest of Former Building 4356. Cobalt-60 was not detected at concentrations exceeding the FALs in any of the surface soil samples collected from Subarea 5B. Subarea 5C In this subarea, 90 surface soil and 129 subsurface soil samples were collected for Co-60 analysis One subsurface soil sample contained Co-60 at a concentration of 0.0247 pCi/g, which exceeded the FAL. This sample was collected south of Building 4100. Cobalt-60 was not detected at concentrations exceeding the FALs in any of the surface soil samples collected from Subarea 5C. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-12 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Subarea 6 In this subarea, 297 surface soil and 345 subsurface soil samples were collected for Co-60 analysis One surface soil sample contained Co-60 at a concentration of 0.0480 pCi/g, exceeding the FAL. This sample was collected from the northwest edge of the SRE Complex. Cobalt-60 was not detected at concentrations exceeding the FALs in any of the subsurface soil samples collected from Subarea 6. Subarea 7 In this subarea, 216 surface soil and 208 subsurface soil samples were collected for Co-60 analysis. One surface soil sample contained Co-60 at a concentration of 0.0264 pCi/g exceeding the FAL. This sample was collected from the RMHF fence line. Cobalt-60 was not detected at concentrations exceeding the FALs in any of the subsurface soil samples collected from Subarea 7. 4.3.5 Europium-152 The FALs for Eu-152 are the 2σ UCL MDCs of 0.670 pCi/g for GEL and 0.0459 pCi/g for TAL. Europium-152 was part of the default analyte suite, therefore all soil samples were analyzed for Eu-152 during the Round 1 soil sampling event and only select locations were analyzed for Eu-152 during the Round 2 soil sampling event. Europium-152 was detected in five soil samples at concentrations greater than the FALs, ranging from 0.049 to 0.165 pCi/g. Europium-152 was detected only in soil samples collected from Subareas 5A and 5B; none of the soil samples collected in the remaining subareas within the Area IV Study Area exhibited Eu-152 above the FALs. These concentrations are presented by subarea (surface and subsurface) in Tables 4.2 and 4.3 and are illustrated on Figures 4.9 and 4.10. Details pertaining to each subarea regarding the distribution of Eu-152 are provided in the following subsections. Subarea 5A In this subarea, 144 surface soil and 219 subsurface soil samples were collected for Eu-152 analysis. Two surface soil samples contained Eu-152 at concentrations exceeding the FALs ranging from 0.073 to 0.165 pCi/g. These samples were collected from one area, Former Building 4005 at the southwest border. Europium-152 was not detected at concentrations exceeding the FAL the subsurface soil samples collected from Subarea 5A. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-13 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Subarea 5B In this subarea, 245 surface soil and 275 subsurface soil samples were collected for Eu-152 analysis. One surface and two subsurface soil samples contained concentrations exceeding the FALs ranging from 0.049 to 0.078 pCi/g. All three of these samples were collected from one area, SNAP Reactor Former Building 4010 Area. Note that one surface and one subsurface sample are geographically located in Subarea 6 but are associated with this feature. 4.3.6 Plutonium-238 The FALs for Pu-238 are the 2σ UCL MDCs of 0.0480 pCi/g for GEL data and 0.00921 pCi/g for TAL data. Plutonium-238 was part of the default analyte suite, therefore all soil samples were analyzed for Pu-238 during the Round 1 soil sampling event; however, only select locations were analyzed for Pu-238 during the Round 2 soil sampling event. Plutonium-238 was detected in two surface soil samples at concentrations greater than the FALs, with concentrations of 0.0137 and 0.0492 pCi/g. Plutonium-238 was detected only in surface soil samples collected from Subareas 5A and 5D. Plutonium-238 was not detected at concentrations exceeding the FALs in any of the subsurface soil samples collected, or in surface soil samples collected from other subareas. Concentrations exceeding FALs are presented by subarea in Tables 4.2 and 4.3 and are illustrated on Figure 4.11. Details pertaining to each subarea regarding the distribution of Pu-238 are provided in the following subsections. Subarea 5A In this subarea, 144 surface soil and 207 subsurface soil samples were collected for Pu-238 analysis. One surface soil sample contained Pu-238 at a concentration of 0.0137 pCi/g exceeding the FAL. This sample was collected from the north side of Former Building 4023. Subarea 5D In this subarea, 236 surface soil and 251 subsurface soil samples were collected for Pu-238 analysis. One surface soil sample contained Pu-238 at a concentration of 0.0492 pCi/g, exceeding the FAL. This sample was collected from the east side of Former Building 4875. 4.3.7 Americium-241 The FALs for Am-241 are the 2σ UCL MDC of 0.041 pCi/g for GEL data and the BTV of 0.0162 pCi/g for TAL data. Americium-241 was part of the default analyte suite, therefore all soil samples were analyzed for Am-241 during the Round 1 soil sampling event; however, only select locations were analyzed for Am-241 during the Round 2 soil sampling event. Americium-241 was detected in one surface and two subsurface soil samples at concentrations exceeding the FALs. Americium-241 was detected only in samples from Subareas 5D and 8. These concentrations are presented by subarea (surface and subsurface) in Tables 4.2 and 4.3 and are illustrated on Figures 4.12 and 4.13. Details pertaining to each subarea regarding the distribution of Am-241 are provided in the following subsections. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-14 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Subarea 5D In this subarea, 229 surface soil and 244 subsurface soil samples were collected for Am-241 analysis. One subsurface soil sample contained Am-241 at a concentration of 0.0589 pCi/g, exceeding the FAL. This sample was collected approximately 300 feet southeast of former Building 4173/4865 from a “trench” aerial photo feature. Americium-241 was not detected at concentrations exceeding the FAL in any of the surface soil samples collected from Subarea 5D. Subarea 8 In this subarea, 153 surface soil and 136 subsurface soil samples were collected for Am-241 analysis. One surface and 1 subsurface soil samples contained Am-241 at concentrations of 0.0514 and 0.0484 pCi/g, respectively, exceeding the FAL. These samples were collected from the following two areas: • • 4.3.8 Former Sodium Disposal Facility (1 subsurface sample) Southwest side of 8-North (1 surface sample) Curium-243/244 The FALs for Cm-232/244 are the 2σ UCL MDCs of 0.0466 pCi/g for GEL data and 0.0162 pCi/g for TAL data. Curium-243/244 was part of the default analyte suite, therefore all soil samples were analyzed for Cm-243/244 during the Round 1 soil sampling event and only select locations were analyzed for Cm-243/244 during the Round 2 soil sampling event. Curium-243/244 was detected in one surface and one subsurface soil sample at concentrations greater than the FALs, at 0.0178 and 0.0647 pCi/g. Curium-243/244 was only detected above the FAL in Subareas 5B and the NBZ. These concentrations are presented by subarea (surface and subsurface) in Tables 4.2 and 4.3 and are illustrated on Figures 4.14 and 4.15. Details pertaining to each subarea regarding the distribution of Cm-243/244 are provided in the following subsections. Subarea 5B In this subarea, 245 surface soil and 275 subsurface soil samples were collected for Cm243/244 analysis. One surface soil sample contained Cm-243/244 at a concentration of 0.0178 pCi/g exceeding the FAL. This sample was collected from the footprint of the former SNAP reactor Building 4010. Curium-243/244 was not detected at concentrations exceeding the FAL in any of the subsurface soil samples collected from Subarea 5B. Northern Buffer Zone In the NBZ, 160 surface soil and 73 subsurface soil samples were collected for Cm-243/244 analysis. One subsurface soil sample exceeded the FAL for Cm-243/244 at a concentration of 0.0647 pCi/g. This sample was collected from the NBZ-East within the Debris Field north of Subarea 6. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-15 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Curium-243/244 was not detected at concentrations exceeding the FAL in any of the surface soil samples collected from the NBZ. 4.3.9 Single Occurrence Radionuclides Europium-154, Ni-59 and H-3 were detected above FALs in one sample each throughout the Area IV Study Area. Europium-154 and H-3 were detected at concentrations equal to their FALs at 0.136 and 7.38 pCi/g (respectively) in samples with other site-related radionuclide above the FALs. Europium-154 was detected in a sample collected from the 5D-South southern ridge and H-3 from the footprint of former Building 4010. Nickel-59 was detected in an isolated sample location within the footprint of former Building 4023 at a concentration of 23.9 pCi/g. These sample results are presented in Tables 4.2 and 4.3. 4.3.10 Naturally Occurring Radioactive Material Naturally occurring radioactive materials are present in soils, sediment, and rock in the earth’s crust. There are two types of naturally occurring radionuclides in soil: those occurring singly and those occurring as part of a decay series. The most common singly occurring NORM radionuclide is potassium (K)-40. Three primordial decay series ubiquitous in rocks and soil originate from Th-232, U-235, and U-238. Each decay series is composed of a radionuclide parent (listed) and its progeny or radioactive decay product radionuclides. Progeny radionuclides are normally present in uncontaminated soil in secular equilibrium (the concentrations of parent and progeny radionuclides are equal). Secular equilibrium enables the inter-comparison of radionuclides within a series to assess individual radionuclide exceedances. An examination of the radionuclide concentration ratios within a series aids in assessing whether NORM radionuclide exceedances may be present due to site-related activities. The differences observed between naturally occurring radionuclide concentrations of a particular series are expected to be small if the soil sample does not represent contamination. For example, a U-238 exceedance of 2.5 pCi/g would be recognized as a higher than normal SSFL sample result. When the U-238 decay product radionuclides (bismuth-214 and lead-214) are approximately 2.5 pCi/g this affirms the U-238 result does not indicate site-related contamination, even though it exceeds the FAL (the modifier approximately is appropriate because concentrations reported from different radiochemistry methods are expected to differ, within the error limits of each method). This scenario suggests the sample has a high natural uranium concentration, within the range of natural variability. Conversely, a U-238 exceedance with a concentration that significantly differed from its decay product radionuclides may indicate site–related contamination. The background study demonstrated that radionuclides are present in unimpacted areas with a degree of variability in concentrations. It is possible that radionuclides could exceed FALs and not be due to SSFL radiological operations. Considering that greater than 3,000 sample analyses were completed for default suite radionuclides, some results will exceed FALs simply due to natural and statistical variability. Natural variability is due to the natural distribution in rock and soil formations. Statistical variability refers to analytical measurements statistics. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-16 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California One of the most important naturally occurring radionuclides is uranium. It is important because it is present and detectable at naturally occurring concentrations and is the primary radioactive element in most nuclear fuel. The U-235 contained in nuclear fuel is enriched or concentrated to approximately 3 percent versus 0.72 percent U-235 in natural uranium. After uranium nuclear fuel is made, the natural isotopic abundance ratios and secular equilibrium conditions of each nuclide within the respective decay series no longer apply. Thus, comparison between uranium isotopes 234, 235, and 238 is useful to understand whether uranium isotopic ratios indicate enrichment. To assess NORM concentrations that exceed FALs, several factors were considered including: • • • • • • • • Are U-238 and Th-232 decay series radionuclide activities consistent within each series? How does the isotopic ratio of concentrations of U-235 compare with U-238 and U234? Does the gamma scanning line of evidence indicate extensive high surface NORM content in the area? Are there rock outcrops immediately adjacent to the location? Is the location of the sample being evaluated just above bedrock? What information is contained in the borehole gamma scanning? Did information provided in the HSA indicate any site operations conducted at the location? Were there any lines of evidence, such as geophysical or aerial photograph, that indicated a potential source for site-related NORM? The answers to these questions, involving site data have been evaluated to determine whether NORM exceedances can be attributed to site-related contamination. For Round 1 sample results, only four NORM RTL exceedances warranted collection of step-out samples during Round 2. Several instances were identified where NORM RTL exceedances were associated with collocated site-related radionuclides. In these instances, Round 2 step-out samples were collected and analyzed to characterize potential site-related contamination. In addition, analytical method uncertainty is addressed by the RTLs and not by the FALs. As a result, the RTL concentrations are greater than their respective FAL concentrations. The evaluation of NORM RTL exceedances produced few results considered potentially siterelated, while virtually all NORM radionuclide results exceeded their respective FALs. 4.3.11 Likely Chemical and Decontamination and Decommissioning Zones During the February 22, 2012, technical review meeting recommendations and action items including those on the topic of LCRZs and LD&DZs were discussed. USEPA understands that most, if not all, surface soil and infrastructure (building structures, concrete slabs, aboveground pipelines and underground pipelines etc.) may be excavated and removed from areas identified as LD&DZ and LCRZ. In accordance with the USEPA’s role under the AOC for Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-17 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Remedial Action (DTSC, 2010) agreement between DTSC and DOE for the SSFL site, USEPA will conduct confirmation soil sampling to verify that site remediation goals have been achieved at all such remediation zones. These follow-on efforts are not included in the current scope of work and will be accomplished using additional external funding. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4-18 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California 5.0 SUMMARY USEPA’s radiological characterization study of the SSFL at Area IV and the NBZ covered a total of 472 acres. Area IV was historically used for research, development, and construction of nuclear reactors and associated equipment. An exhaustive search of the historical record conducted during the HSA did not find documentation of any former operations or land use associated with Area IV within the NBZ. The characterization consisted of an HSA; a gamma radiation survey; an aerial photograph analysis; a geophysical survey and collecting and analyzing soil, groundwater, surface water, and sediment samples from targeted locations. This report discusses the sampling approach and analytical results for surface soil, subsurface soil, and sediment samples collected from specific targeted locations identified from five lines of evidence. The sampling was conducted in two rounds; (1) Round 1 targeted samples collected from specific locations identified by the five lines of evidence (HSA, geophysics, gamma scanning, aerial photo analysis, and field reconnaissance) and (2) Round 2 step-out samples collected adjacent to Round 1 samples that contained radionuclide concentrations greater than the RTL. Soil sampling commenced in October 2010 with Round 1 sediment sampling and was completed in July 2012 with Round 2 soil sampling, totaling 3,542 environmental samples. RTLs were developed as temporary field decision levels for the radionuclides of concern, in the absence of established cleanup levels, and were used with other information to identify Round 2 step-out locations. Look-up Table values for radionuclides have not been established. Look-up Table values will be established by DTSC in accordance with the AOC which states that the Look-up Table will “include both background concentrations as well as minimum detection limits for specific contaminants whose minimum detection limits exceed local background concentrations” (DTSC, 2010). To satisfy the AOC requirement the final radiological data presented in this report were evaluated against either the BTVs or the 2σ UCL MDCs, as applicable. These values are called the FALs. Sample results were compared to FALs to identify Radiological Areas of Interest. A majority of the Radiological Areas of Interest are congregated within specific areas or are associated with key facilities. Figure 5.1 illustrates all sample locations where one or more radionuclides were identified at concentrations greater than their respective FAL. These locations have been grouped into 48 Radiological Areas of Interest, not including the NBZ East and NBZ West, where no specific key feature was present. The Radiological Areas of Interest, the operational history, and associated analytical results are summarized in Table 5.1. Approximately 70 percent of soil samples with radionuclide concentrations greater than the FALs are located within five Area IV Radiological Areas of Interest: • • • • RMHF complex, SRE complex, 17th Street Drainage, Former Fuel Element Storage Facility, and Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 5-1 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California • New Conservation Yard Drainage Area. At least some portion of each of these areas has been designated by DOE as a LCRZ. The remaining Area IV Radiological Areas of interest are characterized by fewer and generally lower concentrations of the radionuclides of concern associate with a former building or some historical operation. Two groupings of a relatively large number of samples with concentrations greater than the FAL were identified in the southern portion of Subareas 5D and 8. These two areas are on a relatively steep hillside in an area where no operational history was identified during the HSA. Additionally, the soil samples collected from these areas represent the Santa Susana Formation, while the remainder of the samples were collected from soils overlying the Chatsworth Formation, suggesting that these slightly elevated concentrations may be attributable to geologic variations and considered NORM. Radiological Areas of Interest identified in the NBZ consist of isolated radionuclide detections; however, Round 2 step-out samples were not collected in the NBZ. Four Round 1 samples in the NBZ East and 12 Round 1 samples in the NBZ West were reported to contain radionuclides at concentrations exceeding the respective FALs. There is no pattern or grouping of the exceedances. Specific locations throughout the Area IV Study Area were designated as LCRZs by DOE and DTSC based on the concentrations of chemical analytes. USEPA understands that these LCRZs will be remediated at a later date; thus, only limited sampling was conducted by USEPA within the LCRZ boundaries. Other areas where limited or no sampling for radiological constituents was conducted included likely LD&DZs which were defined as existing building complexes or existing concrete foundations of former buildings that will likely be removed and remediated as necessary. If these LCRZs and LD&DZs are not remediated additional characterization in these areas may be necessary to identify potential areas of radiological contamination. In accordance with the AOC, DTSC will determine Look-up Table values for comparison to all sample results for determination of locations of contamination that warrant remediation. Results that exceed the FALs and Radiological Areas of Interest identified in this report are potential locations that may require further investigation and/or remediation depending on the Look-up Table values. Areas of contamination requiring remediation will be determined after DTSC establishes the Look-up Table values, and this process is not within the scope of USEPA’s action, nor under EPA purview. USEPA has provided recommendations to the DTSC regarding the future development of LUT values (HGL, 2012g). LUT values are a metric against which analytical sample results will be compared to determine if a sample contains or does not contain contamination requiring remediation. In addition, guidance is provided for the implementation and application of these LUT values, and for addressing potential challenges in the procurement and use of analytical laboratory data. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 5-2 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California 6.0 REFERENCES Bailey, T. and Jahns, R., 1954. Geology of the Transverse Ranges. Chapter 5, Geology of Southern California. California Division of Mines. Bulletin 170. Department of Toxic Substances Control (DTSC), 2007. Consent Order for Corrective Action, Santa Susana Field Laboratory, Simi Hills, Ventura County, California. August. DTSC, 2010. Administrative Order On Consent For Remedial Action, Santa Susana Field Laboratory, Simi Hills, Ventura County, California. December. Energy Technology Engineering Center, 2010. History Overview, United States Department of Energy Web Site. http://www.etec.energy.gov/History/Area-IV-History.html HydroGeoLogic, Inc. (HGL) and Envicom Corporation, 2009. Biological Assessment, Santa Susana Field Laboratory, Ventura County, California. December. HGL, 2010a. Site Management Plan, Santa Susana Field Laboratory Area IV Radiological Study, Ventura County, California. September. HGL and The Palladino Company (TPC), Inc., 2010b. Final Gamma Radiation Scanning Sampling and Analysis Plan, Area IV Radiological Study, Santa Susana Field Laboratory, Ventura County, California. February. HGL, 2010c. Geophysical Investigation Plan, Santa Susana Field Laboratory Area IV Radiological Study, Ventura County, California. April. HGL, 2010d. Final Phase I Field Sampling Plan for Groundwater, Surface Water, and Sediment, Area IV Radiological Study, Santa Susana Field Laboratory Ventura County, California. July. HGL, 2011a. Final Radiological Background Study Report Santa Susana Field Laboratory, Ventura County, California. October. HGL, 2011b. Final Geophysical Investigation Report, Area IV Radiological Study, Santa Susana Field Laboratory Site, Ventura County, California. December. HGL, 2011c. Technical Memorandum, Radiological Trigger Levels, Santa Susana Field Laboratory, Area IV Radiological Study, December. HGL, 2012a. Final Historical Site Assessment, Area IV Radiological Study, Santa Susana Field Laboratory Site, Ventura County, California. October. HGL and TPC, 2012b. Final Gamma Radiation Scanning Report, Area IV Radiological Study, Santa Susana Field Laboratory Site, Ventura County, California. October. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 6-1 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California HGL, 2012c. Final Groundwater Report, Area IV Radiological Study, Santa Susana Field Laboratory Site, Ventura County, California. July. HGL, 2012d. Final Field Sampling Plan for Soil Sampling, Area IV Radiological Study, Santa Susana Field Laboratory Site, Ventura County, California. March. HGL, 2012e. Final Quality Assurance Project Plan for Soil Sampling, Area IV Radiological Study, Santa Susana Field Laboratory Site, Ventura County, California. March. HGL, 2012f. Quality Assurance Split Sample Analysis, Area IV Radiological Study, Santa Susana Field Laboratory Site, Ventura County, California. September. HGL, 2012g. Technical Memorandum, Radiological Look-up Table Recommendations, Santa Susana Field Laboratory, Area IV Radiological Study. December. John Minch and Associates, Inc. 2012. Final Report Cultural Resource Compliance and Monitoring Results for USEPA’s Radiological Study of the Santa Susana Field Laboratory, Area IV and Northern Buffer Zone. October. Montgomery Watson Harza (MWH), 2007. Geologic Characterization of the Central Santa Susana Field Laboratory, Ventura County, California, prepared for The Boeing Company, National Aeronautics and Space Administration, United States Department of Energy. North American Aviation, Inc. (NAA), 1960. The North American Story, December. Regional Water Quality Control Board – Los Angeles Region, 2006. Fact Sheet National Pollutant Discharge Elimination System Permit For The Boeing Company (Santa Susana Field Laboratory). Revised January. U.S. Department of Agriculture (USDA), 2003. U.S. Department of Agriculture, Natural Resources Conservation Service, National Cooperative Soil Survey, Established Series, Rev.GAW/RCH/LCL/ET,03/2003. http://www2.ftw.nrcs.usda.gov/osd/dat/S/ SAUGUS.html U.S. Department of Energy (DOE), 1997. April. Evaluation of Radiochemical Data Usability. U.S. Environmental Protection Agency, U.S. Department of Defense, U.S. Department of Energy, and Nuclear Regulatory Commission, 2000. Multi-Agency Radiation Survey and Site Investigation Manual. August. U.S. Environmental Protection Agency (USEPA), 2004. Multi-Agency Radiological Laboratory Analytical Protocols Manual (MARLAP). July. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 6-2 HydroGeoLogic, Inc. 12/21/2012 HGL—Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California USEPA, 2010. Aerial Photographic Analysis of Santa Susana Field Laboratory – Area IV, Ventura County, California. Volume 1 and Volume 2, March. U.S. Fish and Wildlife Service, 2010. Biological Opinion for the Santa Susana Field Laboratory, Area IV Radiological Study Project, Ventura County, California. May. U.S. Geological Survey (USGS), U.S. Department of the Interior, 1952. Calabasas Quadrangle, California, 7.5 Minute Series (Topographic). Washington State Department of Health, 1996. Environmental Health Programs, Hanford Health Information Network, A List of Radionuclides Released from Hanford, October. Web Site: http://doh.wa.gov/ehp/6-3anford/publications/history/listing.html Weston Solutions, Inc., 2007. Preliminary Assessment/Site Inspection Report, Santa Susana Field Laboratory, Simi Valley, California. November. Yerkes, R.F., and Campbell, R.H., 2005. Preliminary Geologic Map of the Los Angeles 30´ x 60´ Quadrangle, Southern California. USGS open-file report 2005-1019. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 6-3 HydroGeoLogic, Inc. 12/21/2012 This page was intentionally left blank. TABLES This page was intentionally left blank. HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 3.1 Soil Samples Collected and Analyzed in Area IV Study Area Subarea Round 1 Soil Samples Drainage Surface Subsurface 3 0 2 5A 27 5B 1 Round 2 Soil Samples Duplicate Drainage Surface Subsurface Sediment Duplicate Round 1 Total Round 2 Total Total Sediment Random 11 0 0 1 0 0 0 0 0 14 0 14 111 203 0 0 16 0 26 26 0 4 357 56 413 29 193 258 0 0 23 0 23 23 0 3 503 49 552 5C 14 67 122 0 0 10 0 9 10 0 2 213 21 234 5D 15 210 240 0 0 25 2 66 63 0 8 490 139 629 6 24 169 256 4 0 24 3 105 105 8 13 477 234 711 7 9 118 141 2 0 15 4 88 75 0 9 285 176 461 8 17 138 134 5 0 19 0 57 57 0 6 313 120 433 NBZ 30 31 73 29 99 14 0 0 4 7 1 276 12 288 Total 165 1039 1438 40 99 147 9 374 363 15 46 2928 807 3735 Notes: 1 Subareas 5A, 5C, 6 and 7 subsurface samples include the deep borehole samples collected in each subarea. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 4.1 Radionuclides of Concern Field Action Levels Radionuclides GEL FAL TAL FAL Radionuclides Site-related Radiouclides above the FAL Am-241 4.10E-02 1.62E-02 Cm-243/Cm-244 4.66E-02 1.62E-02 Co-60 2.52E-02 2.28E-02 Cs-137 1.93E-01 1.93E-01 Eu-152 6.70E-02 4.59E-02 Eu-154 1.36E-01 1.25E-01 H-3 9.99E+00 7.38E+00 Ni-59 7.24E+00 6.48E-01 Pu-238 4.80E-02 9.21E-03 Pu-239/Pu-240 3.69E-02 1.42E-02 Sr-90/Y-90 3.87E-01 7.50E-02 NORM Radionuclides above the FAL Ac-227 2.67E-01 1.69E-01 Ac-228 2.30E+00 2.30E+00 Bi-212 2.04E+00 2.04E+00 Bi-214 1.57E+00 1.57E+00 K-40 3.05E+01 3.05E+01 Pa-231 1.11E+00 7.91E-01 Pb-212 2.67E+00 2.67E+00 Pb-214 1.68E+00 1.68E+00 Ra-226 1.88E+00 NA Th-228 3.67E+00 3.67E+00 Th-230 2.04E+00 2.04E+00 Th-232 2.95E+00 2.95E+00 Th-234 3.04E+00 3.04E+00 Tl-208 9.23E-01 9.23E-01 U-233/U-234 1.87E+00 1.87E+00 U-235/U-236 1.30E-01 1.30E-01 U-238 1.68E+00 1.68E+00 GEL FAL TAL FAL Radionuclides below the FAL Ag-108m Am-243 C-14 Cd-113m Cf-249 Cm-245/Cm-246 Cm-248 Cs-134 Eu-155 Ho-166m I-129 Na-22 Nb-94 Ni-63 Np-236 Np-237 Np-239 Pm-147 Pu-236 Pu-241 Pu-244 Ra-228 Sb-125 Sn-126 Tc-99 Th-229 Tm-171 NA 3.72E-02 2.54E+00 2.95E+03 NA NA NA 3.00E-02 1.98E-01 3.65E-02 1.60E+00 3.06E-02 2.13E-02 1.78E+00 4.95E-02 5.42E-02 1.77E-01 8.62E+00 5.10E-02 3.73E+00 2.59E-02 NA 3.21E-01 2.33E-02 1.75E+00 1.35E-01 6.59E+01 NA 1.34E-02 2.54E+00 2.95E+03 NA 1.62E-02 2.34E-02 6.88E-02 1.98E-01 3.65E-02 NA 2.95E-02 1.72E-02 8.43E-01 3.68E-02 NA 1.02E-01 NA 1.84E-02 NA 5.26E-03 NA 3.21E-01 1.95E-02 3.87E-01 4.62E-02 6.59E+01 Notes: Refer to Table 2.1 of the Final Field Sampling Plan for Soil Sampling (HGL, 2012d) for a definition of radionuclide symbols. Reporting units in picocuries per gram. FAL - field action level GEL - GEL Laboratories LLC NA - not available NORM - naturally occurring radioactive material TAL - TestAmerica Laboratories, Inc. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 4.2 Surface Soil Analytical Results Exceeding Field Actions Levels Subarea Key Locations/Facilities Location Sample ID Analyzing Laboratory Activity FAL MDC TPU Critical Level GEL 0.0514 0.0410 0.0239 0.0123 0.0097 20016 TAL 0.0178 0.0162 0.0082 0.0048 0.0026 Americium-241 8-North Former Sodium Disposal Facility 8N-00085 40162 Curium-243/244 5B Former Building 4010 5B-00008 Cobalt-60 6 Sodium Reactor Experiment Complex 6-00290 60446 GEL 0.048 0.0252 0.0149 0.00607 0.00834 7 Radioactive Materials Handling Facility 7-00184 70299 GEL 0.0264 J 0.0252 0.0287 0.00978 0.0137 Cesium-137 5A Heavy Metals Likely Chemical Remediation Zone 5A-00042 30321 GEL 0.24 0.193 0.0124 0.014 0.00607 5A Fuel Element Storage Facility 5A-00066 30157 GEL 0.993 0.193 0.0122 0.0529 0.00601 5A Building 4029 5A-00095 30364 GEL 0.2 0.193 0.0121 0.0125 0.00593 5A Fuel Element Storage Facility 5A-00278 30477 GEL 0.595 0.193 0.019 0.0343 0.00927 5A Fuel Element Storage Facility 5A-00279 30479 GEL 0.794 0.193 0.0197 0.0446 0.0096 5A Fuel Element Storage Facility 5A-00280 30481 GEL 0.734 0.193 0.0208 0.0415 0.0101 5A Fuel Element Storage Facility 5A-00281 30483 GEL 0.795 0.193 0.0205 0.0485 0.00999 5A Heavy Metals Likely Chemical Remediation Zone 5A-00282 30485 GEL 0.327 0.193 0.0221 0.0204 0.0107 5B 17th Street Drainage 5B-00211 20455 TAL 0.213 0.193 0.011 0.0094 0.0053 5B 17th Street Drainage 5B-00212 20456 TAL 0.252 0.193 0.019 0.012 0.009 5B 17th Street Drainage 5B-00214 20458 TAL 0.522 0.193 0.014 0.019 0.007 5B 17th Street Drainage 5B-00217 20461 TAL 0.256 0.193 0.0092 0.00996 0.0045 5B 17th Street Drainage 5B-00218 20463 TAL 0.294 0.193 0.017 0.012 0.008 5B 17th Street Drainage 5B-00219 20464 TAL 0.444 0.193 0.014 0.016 0.007 5B 17th Street Drainage 5B-00220 20466 TAL 0.323 0.193 0.009 0.012 0.004 5B 17th Street Drainage 5B-00221 20467 TAL 0.626 0.193 0.013 0.021 0.006 5B 17th Street Drainage 5B-00222 20469 TAL 0.623 0.193 0.01 0.023 0.005 5B 17th Street Drainage 5B-00223 20471 TAL 0.813 0.193 0.011 0.029 0.005 5B 17th Street Drainage 5B-00224 20473 TAL 0.911 0.193 0.015 0.03 0.007 5B 17th Street Drainage 5B-00225 20475 TAL 0.313 0.193 0.011 0.013 0.005 5B Former Building 4010 5B-00289 20101 TAL 0.282 0.193 0.011 0.011 0.005 5B Former Building 4010 5B-00348 20726 GEL 0.254 0.193 0.0165 0.0161 0.00801 5C Building 4100 5C-00056 10081 TAL 0.818 0.193 0.015 0.027 0.007 5C Building 4100 5C-00149 10252 GEL 0.316 0.193 0.0175 0.0201 0.00851 Former Building 4353 5DN-00126 50252 GEL 0.194 0.193 0.0203 0.0149 0.00984 5D-North Hot Lab - Former Building 4020 5DN-00207 50409 GEL 1.42 0.193 0.0188 0.0778 0.00913 5D-South Subarea 5D-South 5DS-00003 50444 GEL 0.196 0.193 0.0196 0.0137 0.0096 5D-South Subarea 5D-South 5DS-00004 50446 GEL 0.227 0.193 0.022 0.0156 0.0107 5D-South Subarea 5D-South 5DS-00012 50462 GEL 0.204 0.193 0.0278 0.0189 0.0135 5D-North Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 1 of 11 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 4.2 Surface Soil Analytical Results Exceeding Field Actions Levels Subarea Key Locations/Facilities Location Sample ID Analyzing Laboratory Activity FAL MDC TPU Critical Level Cesium-137 (Continued) 5D-South Subarea 5D-South 5DS-00017 50472 GEL 0.196 0.193 0.0221 0.0143 0.0108 5D-South Subarea 5D-South 5DS-00043 50640 GEL 0.314 0.193 0.0208 0.0198 0.0101 5D-South Subarea 5D-South 5DS-00048 50650 GEL 0.213 0.193 0.0208 0.0156 0.0101 6 Former Building 4003 - Engineering Test Building 6-00005 60006 GEL 0.241 0.193 0.0148 0.0155 0.00723 6 Former Building 4003 - Engineering Test Building 6-00028 60037 GEL 0.197 0.193 0.0121 0.0125 0.00593 6 Former Building 4003 - Engineering Test Building 6-00029 60039 GEL 0.225 0.193 0.0132 0.0139 0.00645 6 Sodium Reactor Experiment Pond Area 6-00030 60041 GEL 0.229 0.193 0.017 0.0148 0.00827 6 Sodium Reactor Experiment Pond Area 6-00045 60542 GEL 0.389 0.193 0.0226 0.024 0.011 6 Sodium Reactor Experiment Pond Area 6-00063 60100 GEL 0.198 0.193 0.0148 0.013 0.00721 6 Sodium Reactor Experiment Complex 6-00098 60139 GEL 1.19 0.193 0.0161 0.0673 0.00781 6 Liquid and Gas Radioactive Storage Tanks Area 6-00130 60182 GEL 0.355 0.193 0.0215 0.0231 0.0104 6 Liquid and Gas Radioactive Storage Tanks Area 6-00131 60184 GEL 0.535 0.193 0.0178 0.0313 0.00864 6 Liquid and Gas Radioactive Storage Tanks Area 6-00132 60186 GEL 0.257 0.193 0.0188 0.0169 0.00906 6 Liquid and Gas Radioactive Storage Tanks Area 6-00133 60188 GEL 0.422 0.193 0.0173 0.0243 0.00847 6 Liquid and Gas Radioactive Storage Tanks Area 6-00134 60190 GEL 0.935 0.193 0.0223 0.0537 0.0108 6 Liquid and Gas Radioactive Storage Tanks Area 6-00142 60199 GEL 0.596 0.193 0.0177 0.0341 0.00859 6 Liquid and Gas Radioactive Storage Tanks Area 6-00144 60203 GEL 0.321 0.193 0.0148 0.0197 0.00722 6 Liquid and Gas Radioactive Storage Tanks Area 6-00145 60205 GEL 0.378 0.193 0.0152 0.022 0.00743 6 Liquid and Gas Radioactive Storage Tanks Area 6-00146 60207 GEL 2.33 0.193 0.0173 0.123 0.00843 6 Liquid and Gas Radioactive Storage Tanks Area 6-00147 60209 GEL 0.391 0.193 0.0143 0.0226 0.00692 6 Liquid and Gas Radioactive Storage Tanks Area 6-00148 60211 GEL 1.01 0.193 0.0201 0.0579 0.00982 6 Liquid and Gas Radioactive Storage Tanks Area 6-00149 60213 GEL 4.36 0.193 0.0148 0.228 0.00729 6 Sodium Reactor Experiment Complex 6-00150 60215 GEL 1.03 0.193 0.0129 0.0551 0.00634 6 New Conservation Yard 6-00212 60325 GEL 0.513 0.193 0.0168 0.0302 0.00819 6 New Conservation Yard 6-00215 60330 GEL 0.494 0.193 0.0206 0.0314 0.0101 6 New Conservation Yard 6-00228 60349 GEL 0.21 0.193 0.0138 0.0136 0.00676 6 New Conservation Yard 6-00237 60367 GEL 0.325 0.193 0.0154 0.0194 0.00751 6 Sodium Reactor Experiment Complex 6-00278 60422 GEL 0.405 0.193 0.0172 0.0237 0.0084 6 Sodium Reactor Experiment Complex 6-00281 60428 GEL 0.497 0.193 0.0177 0.0301 0.00855 6 Sodium Reactor Experiment Complex 6-00286 60438 GEL 1.09 0.193 0.0145 0.0602 0.00708 6 Sodium Reactor Experiment Complex 6-00287 60440 GEL 0.882 0.193 0.0224 0.0533 0.0108 6 Sodium Reactor Experiment Complex 6-00288 60442 GEL 1.41 0.193 0.0202 0.0764 0.00985 6 Sodium Reactor Experiment Complex 6-00290 60446 GEL 24.3 0.193 0.0217 1.27 0.0107 6 Sodium Reactor Experiment Complex 6-00291 60448 GEL 2.18 0.193 0.0127 0.115 0.00623 6 Sodium Reactor Experiment Complex 6-00292 60450 GEL 0.894 0.193 0.0131 0.0483 0.0064 6 Liquid and Gas Radioactive Storage Tanks Area 6-00293 60452 GEL 46.4 0.193 0.0336 2.47 0.0166 Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 2 of 11 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 4.2 Surface Soil Analytical Results Exceeding Field Actions Levels Subarea Key Locations/Facilities Location Sample ID Analyzing Laboratory Activity FAL MDC TPU Critical Level Cesium-137 (Continued) 6 Liquid and Gas Radioactive Storage Tanks Area 6-00294 60454 GEL 11.3 0.193 0.028 0.63 0.0136 6 Sodium Reactor Experiment Complex 6-00296 60458 GEL 1.35 0.193 0.0123 0.0722 0.00604 6 Sodium Reactor Experiment Complex 6-00297 60460 GEL 2.51 0.193 0.0125 0.132 0.00615 6 Sodium Reactor Experiment Complex 6-00298 60462 GEL 3.02 0.193 0.0129 0.158 0.00633 6 Sodium Reactor Experiment Complex 6-00299 60464 GEL 1.02 0.193 0.0223 0.0569 0.0108 6 Sodium Reactor Experiment Complex 6-00300 60466 GEL 1.44 0.193 0.015 0.0771 0.00727 6 Hot Oil Sodium Cleaning Facility 6-00302 60470 GEL 1.86 0.193 0.0119 0.0979 0.00585 6 Hot Oil Sodium Cleaning Facility 6-00303 60472 GEL 1.18 0.193 0.0149 0.0634 0.00729 6 Hot Oil Sodium Cleaning Facility 6-00304 60474 GEL 0.876 0.193 0.0129 0.0476 0.0063 6 Fuel Element Storage Facility 6-00305 60476 GEL 15.4 0.193 0.0206 0.811 0.0101 6 Fuel Element Storage Facility 6-00306 60478 GEL 196 0.193 0.103 10.2 0.0515 6 Fuel Element Storage Facility 6-00307 60480 GEL 2.84 0.193 0.0118 0.149 0.00577 6 Fuel Element Storage Facility 6-00309 60484 GEL 1.27 0.193 0.0133 0.069 0.00652 6 New Conservation Yard 6-00310 60486 GEL 1.31 0.193 0.0134 0.0694 0.00656 6 Old Conservation Yard 6-00311 60488 GEL 3.42 0.193 0.0181 0.181 0.00886 6 Old Conservation Yard 6-00312 60490 GEL 0.201 0.193 0.012 0.0139 0.00578 6 New Conservation Yard 6-00314 60494 GEL 4.61 0.193 0.0178 0.154 0.0178 6 New Conservation Yard 6-00315 60496 GEL 3.29 0.193 0.0154 0.177 0.00754 6 New Conservation Yard 6-00316 60498 GEL 1.49 0.193 0.0129 0.079 0.00631 6 New Conservation Yard 6-00318 60502 GEL 0.622 0.193 0.0143 0.0345 0.00701 6 New Conservation Yard 6-00320 60506 GEL 0.228 0.193 0.0119 0.0134 0.00584 6 Fuel Element Storage Facility 6-00322 60510 GEL 0.485 0.193 0.0144 0.0271 0.00707 6 Liquid and Gas Radioactive Storage Tanks Area 6-00328 60558 GEL 0.23 0.193 0.018 0.0183 0.00873 6 Liquid and Gas Radioactive Storage Tanks Area 6-00329 60560 GEL 0.22 0.193 0.0172 0.0145 0.00835 6 Liquid and Gas Radioactive Storage Tanks Area 6-00330 60562 GEL 0.324 0.193 0.0193 0.0201 0.00938 6 Liquid and Gas Radioactive Storage Tanks Area 6-00333 60568 GEL 0.401 0.193 0.0198 0.0248 0.00962 6 Liquid and Gas Radioactive Storage Tanks Area 6-00334 60570 GEL 0.51 0.193 0.0192 0.0311 0.00937 6 Liquid and Gas Radioactive Storage Tanks Area 6-00335 60572 GEL 1.15 0.193 0.016 0.0632 0.00782 6 Liquid and Gas Radioactive Storage Tanks Area 6-00336 60574 GEL 0.243 0.193 0.019 0.0174 0.00918 6 Liquid and Gas Radioactive Storage Tanks Area 6-00339 60580 GEL 0.224 0.193 0.0149 0.0142 0.00723 6 Sodium Reactor Experiment Complex 6-00340 60582 GEL 0.371 0.193 0.0164 0.0223 0.00798 6 Sodium Reactor Experiment Complex 6-00341 60584 GEL 1.23 0.193 0.0169 0.0661 0.00826 6 Sodium Reactor Experiment Complex 6-00348 60598 GEL 0.256 0.193 0.0178 0.0165 0.00864 6 Sodium Reactor Experiment Complex 6-00350 60602 GEL 0.689 0.193 0.0176 0.0382 0.0086 6 Sodium Reactor Experiment Complex 6-00354 60610 GEL 0.393 0.193 0.0217 0.0248 0.0105 6 Sodium Reactor Experiment Pond Area 6-00357 60616 GEL 0.253 0.193 0.0208 0.0168 0.0102 Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3 of 11 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 4.2 Surface Soil Analytical Results Exceeding Field Actions Levels Subarea Key Locations/Facilities Location Sample ID Analyzing Laboratory Activity FAL MDC TPU Critical Level Cesium-137 (Continued) 6 Hot Oil Sodium Cleaning Facility 6-00359 60620 GEL 0.509 0.193 0.0174 0.0304 0.00846 6 Hot Oil Sodium Cleaning Facility 6-00360 60622 GEL 0.459 0.193 0.016 0.0264 0.00777 6 Hot Oil Sodium Cleaning Facility 6-00361 60624 GEL 0.739 0.193 0.0182 0.0458 0.00883 6 Hot Oil Sodium Cleaning Facility 6-00363 60628 GEL 0.307 0.193 0.0143 0.0187 0.00697 6 Hot Oil Sodium Cleaning Facility 6-00364 60630 GEL 2.45 0.193 0.0188 0.131 0.00915 6 Former Building 4003 - Engineering Test Building 6-00366 60634 GEL 0.211 0.193 0.0171 0.0157 0.00835 6 Fuel Element Storage Facility 6-00382 60666 GEL 0.288 0.193 0.0222 0.0221 0.0108 6 Fuel Element Storage Facility 6-00384 60670 GEL 0.219 0.193 0.0167 0.0141 0.00812 6 Fuel Element Storage Facility 6-00385 60672 GEL 0.35 0.193 0.0135 0.0205 0.00657 6 New Conservation Yard 6-00394 60690 GEL 0.334 0.193 0.0165 0.0206 0.00804 6 New Conservation Yard 6-00410 60722 GEL 0.382 0.193 0.0275 0.0256 0.0133 6 Sodium Reactor Experiment Complex 6-00424 60761 GEL 0.407 0.193 0.023 0.0258 0.0112 6 Sodium Reactor Experiment Pond Area EPASED17 EPASED17 TAL 0.208 0.193 0.02 0.013 0.01 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00003 70005 GEL 2.5 0.193 0.0126 0.135 0.00611 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00004 70007 GEL 2.35 0.193 0.0191 0.126 0.0093 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00005 70009 GEL 1.38 0.193 0.0206 0.075 0.00999 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00006 70011 GEL 0.24 0.193 0.0233 0.022 0.0113 7 Radioactive Materials Handling Facility 7-00007 70013 GEL 2.84 0.193 0.0155 0.152 0.00756 7 Radioactive Materials Handling Facility 7-00008 70015 GEL 0.968 0.193 0.0179 0.0539 0.00871 7 Radioactive Materials Handling Facility 7-00009 70017 GEL 2.66 0.193 0.0144 0.144 0.007 7 Radioactive Materials Handling Facility 7-00010 70019 GEL 9.21 0.193 0.0237 0.496 0.0116 7 Radioactive Materials Handling Facility Leach Field 7-00011 70021 GEL 1.75 0.193 0.0177 0.0958 0.00861 7 Radioactive Materials Handling Facility Leach Field 7-00012 70023 GEL 1.14 0.193 0.0174 0.0639 0.00845 7 Radioactive Materials Handling Facility Leach Field 7-00013 70025 GEL 2.77 0.193 0.0168 0.148 0.00818 7 Radioactive Materials Handling Facility 7-00014 70027 GEL 2.68 J 0.193 0.0184 0.143 0.00896 7 Radioactive Materials Handling Facility Leach Field 7-00015 70029 GEL 4.7 0.193 0.0167 0.157 0.0167 7 Radioactive Materials Handling Facility Leach Field 7-00016 70031 GEL 1.08 0.193 0.0165 0.0584 0.00806 7 Radioactive Materials Handling Facility 7-00017 70033 GEL 6.21 0.193 0.0191 0.325 0.00932 7 Radioactive Materials Handling Facility 7-00018 70035 GEL 0.611 J 0.193 0.0184 0.0353 0.00898 7 Radioactive Materials Handling Facility Leach Field 7-00020 70039 GEL 0.234 0.193 0.0173 0.0173 0.00843 7 Radioactive Materials Handling Facility 7-00021 70041 GEL 0.528 J 0.193 0.0206 0.0312 0.01 7 Radioactive Materials Handling Facility 7-00022 70043 GEL 1.23 0.193 0.0172 0.0698 0.00834 7 Radioactive Materials Handling Facility Leach Field 7-00023 70045 GEL 1.16 0.193 0.0184 0.066 0.00894 7 Radioactive Materials Handling Facility 7-00024 70047 GEL 0.25 0.193 0.0212 0.0174 0.0103 7 Radioactive Materials Handling Facility Leach Field 7-00025 70049 GEL 0.374 0.193 0.0166 0.0235 0.00806 7 Interim Storage Facility - Former Building 4654 7-00026 70051 GEL 0.674 0.193 0.0217 0.0395 0.0105 Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4 of 11 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 4.2 Surface Soil Analytical Results Exceeding Field Actions Levels Subarea Key Locations/Facilities Location Sample ID Analyzing Laboratory Activity FAL MDC TPU Critical Level Cesium-137 (Continued) 7 Hazardous Waste Management Facility - Former Building 4133 7-00027 70053 GEL 2.53 0.193 0.0181 0.134 0.00881 7 Interim Storage Facility - Former Building 4654 7-00028 70055 GEL 1.29 0.193 0.0202 0.0707 0.00975 7 Interim Storage Facility - Former Building 4654 7-00029 70057 GEL 1.81 0.193 0.0174 0.0993 0.00849 7 Interim Storage Facility - Former Building 4654 7-00030 70059 GEL 1.45 J 0.193 0.0196 0.0782 0.00954 7 Hazardous Waste Management Facility 7-00031 70061 GEL 0.684 0.193 0.0168 0.0398 0.00815 7 Hazardous Waste Management Facility 7-00032 70063 GEL 1.74 0.193 0.0189 0.0936 0.00921 7 Hazardous Waste Management Facility 7-00033 70065 GEL 0.778 0.193 0.0165 0.0433 0.00803 7 Hazardous Waste Management Facility 7-00034 70067 GEL 0.193 0.0151 0.0629 0.00732 7 Interim Storage Facility - Former Building 4654 7-00036 70071 GEL 0.193 0.0163 0.0456 0.00791 7 Subarea 7 Northern Panhandle 7-00037 70073 GEL 0.193 0.0246 1.05 0.0121 7 Hazardous Waste Management Facility - Former Building 4133 7-00038 70075 GEL 0.704 0.193 0.0172 0.0393 0.00841 7 Subarea 7 Northern Panhandle 7-00041 70081 GEL 0.214 J 0.193 0.0146 0.014 0.00712 7 Radioactive Materials Handling Facility 7-00045 70089 GEL 3.6 0.193 0.019 0.196 0.00926 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00049 70097 GEL 0.213 0.193 0.0166 0.014 0.00807 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00050 70099 GEL 0.763 0.193 0.0175 0.0437 0.00853 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00051 70101 GEL 0.493 0.193 0.0173 0.0278 0.00846 7 Radioactive Materials Handling Facility 7-00052 70103 GEL 6.59 0.193 0.0191 0.363 0.00932 7 Radioactive Materials Handling Facility 7-00053 70105 GEL 0.885 0.193 0.0174 0.049 0.00846 7 Radioactive Materials Handling Facility 7-00054 70107 GEL 1.42 0.193 0.0162 0.0771 0.00787 7 Radioactive Materials Handling Facility 7-00055 70109 GEL 0.399 0.193 0.016 0.0232 0.00776 7 Subarea 7 Northern Panhandle 7-00070 70129 GEL 6.17 J 0.193 0.02 0.324 0.00979 7 Subarea 7 Northern Panhandle 7-00071 70131 GEL 0.43 J 0.193 0.0177 0.0267 0.00861 7 Interim Storage Facility - Former Building 4654 7-00073 70134 GEL 0.974 J 0.193 0.0151 0.0526 0.00732 7 Interim Storage Facility - Former Building 4654 7-00077 70140 GEL 0.249 0.193 0.0178 0.0172 0.00865 7 Radioactive Materials Handling Facility 7-00083 70148 GEL 1.82 0.193 0.0215 0.0984 0.0105 7 Radioactive Materials Handling Facility 7-00086 70153 GEL 4.55 0.193 0.0169 0.249 0.00823 7 Radioactive Materials Handling Facility 7-00087 70155 GEL 19.8 0.193 0.021 1.03 0.0103 7 Radioactive Materials Handling Facility 7-00090 70161 GEL 6.52 0.193 0.0165 0.342 0.00805 7 Radioactive Materials Handling Facility 7-00091 70163 GEL 0.86 0.193 0.0192 0.0489 0.00932 7 Radioactive Materials Handling Facility 7-00092 70165 GEL 1.5 0.193 0.0174 0.0826 0.00846 7 Radioactive Materials Handling Facility 7-00093 70167 GEL 1.41 0.193 0.0156 0.0771 0.00758 7 Radioactive Materials Handling Facility 7-00094 70169 GEL 0.484 0.193 0.0174 0.0285 0.00849 7 Radioactive Materials Handling Facility 7-00095 70171 GEL 1.78 J 0.193 0.0213 0.0962 0.0103 7 Radioactive Materials Handling Facility 7-00096 70173 GEL 0.344 J 0.193 0.0178 0.021 0.00867 7 Radioactive Materials Handling Facility 7-00097 70175 GEL 1.04 J 0.193 0.0209 0.06 0.0102 7 Radioactive Materials Handling Facility 7-00101 70183 GEL 1.54 0.193 0.0153 0.0819 0.00748 Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 5 of 11 1.17 J 0.833 20.2 J HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 4.2 Surface Soil Analytical Results Exceeding Field Actions Levels Subarea Key Locations/Facilities Location Sample ID Analyzing Laboratory Activity FAL MDC TPU Critical Level Cesium-137 (Continued) 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00122 70208 GEL 0.195 0.193 0.0222 0.0145 0.0108 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00129 70217 GEL 0.464 0.193 0.0158 0.0267 0.00771 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00130 70219 GEL 2.04 0.193 0.0153 0.108 0.00746 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00134 70226 GEL 0.578 0.193 0.0153 0.0327 0.00744 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00135 70228 GEL 1.33 0.193 0.019 0.0736 0.00924 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00136 70230 GEL 1.28 0.193 0.0225 0.0704 0.0109 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00137 70232 GEL 1.05 0.193 0.0156 0.0603 0.00756 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00138 70234 GEL 0.865 0.193 0.0177 0.0477 0.00863 7 Radioactive Materials Handling Facility Leach Field 7-00139 70236 GEL 0.387 0.193 0.0217 0.0271 0.0106 7 Radioactive Materials Handling Facility Leach Field 7-00140 70238 GEL 0.21 0.193 0.0174 0.0151 0.00847 7 Radioactive Materials Handling Facility Leach Field 7-00141 70240 GEL 0.791 0.193 0.0217 0.0443 0.0106 7 Radioactive Materials Handling Facility Leach Field 7-00142 70242 GEL 0.803 0.193 0.0154 0.0438 0.00752 7 Radioactive Materials Handling Facility Leach Field 7-00143 70244 GEL 0.223 0.193 0.0215 0.0161 0.0105 0.253 0.193 0.0147 0.0155 0.00715 0.193 0.0173 0.0608 0.00841 7 Hazardous Waste Management Facility 7-00144 70246 GEL 7 Hazardous Waste Management Facility 7-00146 70250 GEL 7 Radioactive Materials Handling Facility 7-00151 70256 GEL 0.498 0.193 0.0236 0.0316 0.0114 7 Radioactive Materials Handling Facility 7-00157 70263 GEL 2.01 0.193 0.0172 0.109 0.00836 7 Radioactive Materials Handling Facility 7-00176 70286 GEL 1.21 0.193 0.0163 0.0654 0.00795 7 Subarea 7 Northern Panhandle 7-00178 70289 GEL 8.86 J 0.193 0.021 0.466 0.0103 7 Radioactive Materials Handling Facility 7-00179 70291 GEL 0.202 0.193 0.0172 0.0141 0.00837 7 Hazardous Waste Management Facility 7-00183 70297 GEL 0.396 0.193 0.0173 0.0234 0.00837 7 Radioactive Materials Handling Facility 7-00184 70299 GEL 0.253 0.193 0.0243 0.0208 0.0118 7 Subarea 7 Northern Panhandle 7-00189 70423 GEL 0.486 J 0.193 0.0167 0.0281 0.00808 7 Subarea 7 Northern Panhandle 7-00190 70425 GEL 0.199 J 0.193 0.0178 0.0137 0.00867 7 Subarea 7 Northern Panhandle 7-00191 70427 GEL 0.309 J 0.193 0.0154 0.019 0.00747 7 Subarea 7 Northern Panhandle 7-00194 70433 GEL 0.456 0.193 0.0195 0.0277 0.00942 7 Subarea 7 Northern Panhandle 7-00195 70435 GEL 0.277 0.193 0.0176 0.0181 0.00854 7 Hazardous Waste Management Facility 7-00196 70330 GEL 0.38 0.193 0.0153 0.0226 0.00744 7 Hazardous Waste Management Facility 7-00197 70332 GEL 0.244 0.193 0.0151 0.0158 0.00733 7 Hazardous Waste Management Facility 7-00198 70334 GEL 0.324 0.193 0.0166 0.0194 0.00806 7 Hazardous Waste Management Facility 7-00202 70342 GEL 1.91 0.193 0.0166 0.104 0.00808 7 Hazardous Waste Management Facility 7-00204 70344 GEL 0.626 0.193 0.0161 0.0359 0.00783 7 Hazardous Waste Management Facility 7-00205 70345 GEL 0.324 0.193 0.0146 0.0195 0.0071 7 Hazardous Waste Management Facility 7-00206 70346 GEL 0.236 0.193 0.0169 0.0161 0.00821 7 Hazardous Waste Management Facility 7-00210 70351 GEL 0.955 0.193 0.0173 0.0538 0.00841 7 Hazardous Waste Management Facility 7-00212 70353 GEL 0.406 0.193 0.0179 0.0235 0.00873 Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 6 of 11 1.12 J HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 4.2 Surface Soil Analytical Results Exceeding Field Actions Levels Subarea Key Locations/Facilities Location Sample ID Analyzing Laboratory Activity FAL MDC TPU Critical Level Cesium-137 (Continued) 7 Hazardous Waste Management Facility 7-00213 70354 GEL 0.325 0.193 0.0192 0.02 0.00935 7 Hazardous Waste Management Facility 7-00214 70355 GEL 0.878 0.193 0.0173 0.0482 0.00841 7 Hazardous Waste Management Facility 7-00215 70356 GEL 0.66 0.193 0.0199 0.0392 0.00972 7 Hazardous Waste Management Facility 7-00216 70409 GEL 0.297 0.193 0.0171 0.0186 0.00836 7 Hazardous Waste Management Facility 7-00218 70358 GEL 0.605 0.193 0.019 0.0378 0.0092 7 Hazardous Waste Management Facility 7-00219 70413 GEL 0.348 0.193 0.0189 0.0211 0.00923 7 Hazardous Waste Management Facility 7-00223 70364 GEL 0.556 0.193 0.016 0.0321 0.00779 7 Hazardous Waste Management Facility 7-00224 70366 GEL 0.229 0.193 0.0137 0.0147 0.00665 7 Hazardous Waste Management Facility 7-00225 70394 GEL 0.704 0.193 0.0197 0.0398 0.00956 7 Radioactive Materials Handling Facility Leach Field 7-00232 70372 GEL 0.199 0.193 0.0136 0.0128 0.00662 7 Radioactive Materials Handling Facility Leach Field 7-00233 70437 GEL 0.296 0.193 0.017 0.0182 0.00823 7 Radioactive Materials Handling Facility Leach Field 7-00235 70439 GEL 0.307 0.193 0.0148 0.0185 0.00719 7 Radioactive Materials Handling Facility Leach Field 7-00236 70440 GEL 1.03 0.193 0.0185 0.0566 0.00896 7 Radioactive Materials Handling Facility Leach Field 7-00246 70328 GEL 0.211 0.193 0.0187 0.0158 0.0091 7 Radioactive Materials Handling Facility Leach Field 7-00247 70329 GEL 0.718 0.193 0.0188 0.0403 0.00913 7 Radioactive Materials Handling Facility Leach Field 7-00248 70450 GEL 0.568 0.193 0.0203 0.0342 0.00988 7 Radioactive Materials Handling Facility Leach Field 7-00251 70456 GEL 0.93 0.193 0.0155 0.0517 0.00754 7 Radioactive Materials Handling Facility Leach Field 7-00252 70458 GEL 0.662 0.193 0.0189 0.0406 0.00917 7 Radioactive Materials Handling Facility Leach Field 7-00253 70460 GEL 0.976 0.193 0.0198 0.0592 0.00958 7 Radioactive Materials Handling Facility Leach Field 7-00254 70462 GEL 0.732 0.193 0.0177 0.0406 0.00863 7 Radioactive Materials Handling Facility Leach Field 7-00255 70463 GEL 0.725 0.193 0.0179 0.0418 0.00869 7 Radioactive Materials Handling Facility Leach Field 7-00256 70464 GEL 0.973 0.193 0.0164 0.0534 0.00796 7 Radioactive Materials Handling Facility Leach Field 7-00257 70465 GEL 0.447 0.193 0.0175 0.0274 0.00851 7 Radioactive Materials Handling Facility 7-00263 70398 GEL 0.984 0.193 0.0153 0.0551 0.00741 7 Radioactive Materials Handling Facility 7-00267 70400 GEL 0.652 0.193 0.0171 0.0363 0.00832 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00268 70378 GEL 0.655 0.193 0.0175 0.0364 0.0085 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00269 70380 GEL 0.824 0.193 0.0168 0.0496 0.00815 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00270 70386 GEL 0.858 0.193 0.0171 0.0477 0.00832 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00271 70415 GEL 0.416 0.193 0.0172 0.0244 0.0084 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00272 70382 GEL 0.445 0.193 0.0186 0.0267 0.00908 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00274 70417 GEL 0.233 0.193 0.0151 0.0152 0.00732 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00278 70406 GEL 0.402 0.193 0.0168 0.0236 0.00819 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00279 70390 GEL 0.509 0.193 0.0251 0.0328 0.0121 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00280 70402 GEL 0.283 0.193 0.0204 0.019 0.0099 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00281 70404 GEL 0.237 0.193 0.0146 0.0154 0.00711 8 Former Sodium Disposal Facility EPASED06 EPASED06 TAL 0.205 0.193 0.014 0.01 0.007 Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 7 of 11 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 4.2 Surface Soil Analytical Results Exceeding Field Actions Levels Subarea Key Locations/Facilities Location Sample ID Analyzing Laboratory Activity FAL MDC TPU Critical Level Cesium-137 (Continued) 8-North Former Sodium Disposal Facility 8N-00082 40156 GEL 0.197 0.193 0.0187 0.0138 0.00911 8-North 4056 Landfill 8N-00137 40253 GEL 0.878 0.193 0.0221 0.0533 0.0107 8-North Empire State Atomic Development Association 8N-00199 40446 GEL 0.206 0.193 0.0175 0.0143 0.00849 8-South Subarea 8-South 8S-00010 40298 GEL 0.266 J 0.193 0.0158 0.0169 0.00763 8-South Subarea 8-South 8S-00011 40300 GEL 0.212 0.193 0.0165 0.0137 0.00799 8-South Subarea 8-South 8S-00026 40414 GEL 0.233 0.193 0.0195 0.016 0.0095 8-South Subarea 8-South 8S-00037 40425 GEL 0.726 0.193 0.0178 0.0416 0.00862 0.0176 0.0188 0.00856 NBZ Subarea 7 Northern Panhandle NBZ-00029 90050 GEL 0.26 0.193 NBZ Northern Buffer Zone East NBZ-00111 90169 GEL 0.277 0.193 0.018 0.0179 0.00879 NBZ Northern Buffer Zone West NBZ-00154 90212 GEL 0.207 0.193 0.0148 0.0134 0.00717 NBZ Northern Buffer Zone East NBZ-00197 90186 GEL 0.212 0.193 0.0189 0.0146 0.00918 Europium-152 5A Building 4005 5A-00180 30214 TAL 0.073 0.0459 0.032 0.015 0.016 5A Building 4005 5A-00181 30216 TAL 0.165 0.0459 0.026 0.015 0.013 5B Former Building 4010 5B-00332 20701 TAL 0.078 0.0459 0.025 0.011 0.012 GEL 0.136 J 0.1360 0.0929 0.0444 0.0457 Europium-154 5D-South Subarea 5D-South 5DS-00023 50484 Plutonium-238 5A 5D-North Former Building 4023 Former 4875 5A-00017 30035 TAL 0.0137 0.00921 0.015 0.0046 0.0033 5DN-00117 50234 GEL 0.0492 0.0480 0.0286 0.0148 0.0101 Plutonium-239/240 5C Building 4100 5C 5D-South 5C-00056 10081 TAL 0.0233 0.0142 0.0012 0.0034 0.0012 Building 4015 5C-00141 10242 TAL 0.0487 0.0142 0.0013 0.0053 0.0013 Subarea 5D-South 5DS-00006 50450 GEL 0.0502 0.0369 0.0283 0.0131 0.0117 6 Sodium Reactor Experiment Complex 6-00290 60446 GEL 0.0515 0.0369 0.0294 0.0147 0.0111 6 Hot Oil Sodium Cleaning Pad 6-00303 60472 GEL 0.038 0.0369 0.00903 0.0073 0.00285 6 Sodium Reactor Experiment Pond Area EPASED17 EPASED17 TAL 0.0302 J 0.0142 0.0014 0.0041 0.0013 7 Radioactive Materials Handling Facility 7-00090 70161 GEL 0.0475 0.0369 0.0363 0.0156 0.0143 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00135 70228 GEL 0.0702 0.0369 0.0201 0.0158 0.00622 7 Outfall 3 OF03-003 0F03-003-SS-0 TAL 0.0323 0.0142 0.0048 0.0042 0.0018 NBZ-00026 90044 GEL 0.0384 0.0369 0.022 0.0109 0.0083 NBZ Radioactive Materials Handling Facility Leach Field Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 8 of 11 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 4.2 Surface Soil Analytical Results Exceeding Field Actions Levels Subarea Key Locations/Facilities Location Sample ID Analyzing Laboratory Activity FAL MDC TPU Critical Level Strontium-90 5A Kinetic Experiment Water Boiler 5A-00134 30150 TAL 0.091 0.0750 0.048 0.017 0.027 5B Building 4006 5B-00071 20177 TAL 0.125 0.0750 0.056 0.02 0.031 5B Building 4006 5B-00092 20223 TAL 0.096 0.0750 0.066 0.022 0.038 5B Former Building 4010 5B-00316 20695 TAL 0.563 0.0750 0.051 0.039 0.029 5C-00080 10120 TAL 0.098 0.0750 0.062 0.021 0.035 5D-North 5C Building 4009 Former Building 4462 5DN-00006 50010 GEL 1.55 0.387 0.174 0.184 0.102 5D-North Hot Lab - Former Building 4020 5DN-00008 50014 GEL 0.821 0.387 0.31 0.146 0.189 5D-North Hot Lab - Former Building 4020 5DN-00023 50046 GEL 0.417 0.387 0.23 0.0989 0.134 5D-North Hot Lab - Former Building 4020 5DN-00050 50112 GEL 0.45 0.387 0.171 0.0852 0.1 5D-North Building 4055 - Former Liquid Waste Holdup System 5DN-00065 50139 GEL 0.395 0.387 0.141 0.0731 0.0819 5D-North Former Building 4373 Leach Field 5DN-00089 50180 GEL 0.52 0.387 0.297 0.127 0.172 5D-North Former Building 4353 5DN-00143 50286 GEL 1.27 0.387 0.174 0.159 0.105 5D-North Former Building 4353 5DN-00144 50288 GEL 0.619 0.387 0.317 0.14 0.189 5D-North Former Buildings 4173/4865 5DN-00162 50322 GEL 0.648 0.387 0.181 0.107 0.105 5D-North Hot Lab - Former Building 4020 5DN-00207 50409 GEL 0.631 0.387 0.224 0.122 0.129 5D-North Hot Lab - Former Building 4020 5DN-00213 50528 GEL 0.408 0.387 0.245 0.099 0.146 5D-North Hot Lab - Former Building 4020 5DN-00228 50558 GEL 0.673 0.387 0.243 0.125 0.142 5D-North Former Building 4875 5DN-00236 50574 GEL 0.643 0.387 0.327 0.133 0.202 5D-North Former Building 4353 5DN-00248 50598 GEL 0.422 0.387 0.221 0.0896 0.14 5D-South Subarea 5D-South 5DS-00023 50484 GEL 0.448 0.387 0.24 0.103 0.141 6 Sodium Reactor Experiment Complex 6-00098 60139 GEL 0.392 0.387 0.181 0.0784 0.11 6 Liquid and Gas Radioactive Storage Tanks Area 6-00131 60184 GEL 0.523 0.387 0.201 0.102 0.116 6 Liquid and Gas Radioactive Storage Tanks Area 6-00134 60190 GEL 1.07 0.387 0.148 0.131 0.0886 6 Liquid and Gas Radioactive Storage Tanks Area 6-00142 60199 GEL 0.56 0.387 0.142 0.0848 0.0847 6 Liquid and Gas Radioactive Storage Tanks Area 6-00149 60213 GEL 0.981 0.387 0.708 0.276 0.412 6 Fuel Element Storage Facility 6-00243 60379 GEL 0.557 J 0.387 0.703 0.235 0.414 6 Sodium Reactor Experiment Complex 6-00283 60432 GEL 0.478 0.387 0.123 0.0761 0.071 6 Sodium Reactor Experiment Complex 6-00290 60446 GEL 21.3 0.387 0.229 1.99 0.135 6 Liquid and Gas Radioactive Storage Tanks Area 6-00294 60454 GEL 2.39 J 0.387 0.187 0.258 0.113 6 Sodium Reactor Experiment Pond Area 6-00358 60618 GEL 0.617 0.387 0.254 0.119 0.152 6 Sodium Reactor Experiment Pond Area EPASED19 EPASED19 TAL 0.185 J 0.0750 0.06 0.024 0.034 7 Radioactive Materials Handling Facility 7-00009 70017 GEL 0.491 0.387 0.364 0.134 0.223 7 Radioactive Materials Handling Facility 7-00010 70019 GEL 1.19 0.387 0.142 0.145 0.0854 7 Radioactive Materials Handling Facility Leach Field 7-00012 70023 GEL 0.392 0.387 0.277 0.105 0.171 7 Radioactive Materials Handling Facility Leach Field 7-00013 70025 GEL 0.498 0.387 0.215 0.097 0.133 7 Radioactive Materials Handling Facility 7-00014 70027 GEL 0.757 0.387 0.339 0.151 0.209 Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 9 of 11 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 4.2 Surface Soil Analytical Results Exceeding Field Actions Levels Subarea Key Locations/Facilities Location Sample ID Analyzing Laboratory Activity FAL MDC TPU Critical Level Strontium-90 (Continued) 7 Radioactive Materials Handling Facility Leach Field 7-00015 70029 GEL 14.3 0.387 0.223 1.37 0.131 7 Radioactive Materials Handling Facility Leach Field 7-00016 70031 GEL 0.444 0.387 0.154 0.0813 0.0917 7 Radioactive Materials Handling Facility Leach Field 7-00020 70039 GEL 0.445 0.387 0.264 0.104 0.165 7 Interim Storage Facility - Former Building 4654 7-00029 70057 GEL 0.93 0.387 0.264 0.145 0.165 7 Interim Storage Facility - Former Building 4654 7-00030 70059 GEL 0.696 0.387 0.249 0.123 0.154 7 Interim Storage Facility - Former Building 4654 7-00036 70071 GEL 0.435 0.387 0.255 0.103 0.159 7 Subarea 7 Northern Panhandle 7-00037 70073 GEL 4.2 J 0.387 0.375 0.449 0.238 7 Subarea 7 Northern Panhandle 7-00041 70081 GEL 2.12 J 0.387 0.285 0.275 0.167 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00046 70091 GEL 1.64 J 0.387 0.291 0.214 0.175 7 Radioactive Materials Handling Facility Leach Field 7-00067 70123 GEL 2.11 0.387 0.143 0.222 0.0865 7 Subarea 7 Northern Panhandle 7-00070 70129 GEL 0.647 0.387 0.291 0.129 0.18 7 Subarea 7 Northern Panhandle 7-00071 70131 GEL 0.742 0.387 0.224 0.13 0.131 7 Interim Storage Facility - Former Building 4654 7-00078 70142 GEL 0.467 0.387 0.158 0.085 0.0942 7 Radioactive Materials Handling Facility Leach Field 7-00139 70236 GEL 1.25 0.387 0.245 0.178 0.147 7 Radioactive Materials Handling Facility Leach Field 7-00140 70238 GEL 0.996 0.387 0.235 0.15 0.142 7 Subarea 7 Northern Panhandle 7-00143 70244 GEL 0.983 0.387 0.305 0.161 0.189 7 Hazardous Waste Management Facility 7-00146 70250 GEL 0.43 0.387 0.362 0.128 0.229 7 Radioactive Materials Handling Facility 7-00151 70256 GEL 0.608 0.387 0.239 0.111 0.15 7 Radioactive Materials Handling Facility 7-00157 70263 GEL 0.557 0.387 0.224 0.103 0.137 7 Subarea 7 Northern Panhandle 7-00178 70289 GEL 0.387 0.396 0.284 0.253 7 Radioactive Materials Handling Facility Leach Field 7-00181 70294 GEL 0.977 0.387 0.25 0.146 0.155 7 Radioactive Materials Handling Facility Leach Field 7-00238 70442 GEL 0.445 0.387 0.16 0.0869 0.0899 7 Radioactive Materials Handling Facility Leach Field 7-00249 70452 GEL 1.27 0.387 0.167 0.163 0.0949 7 Radioactive Materials Handling Facility Leach Field 7-00251 70456 GEL 5.37 0.387 0.265 0.544 0.159 7 Radioactive Materials Handling Facility Leach Field 7-00252 70458 GEL 5 0.387 0.374 0.534 0.231 7 Radioactive Materials Handling Facility Leach Field 7-00253 70460 GEL 2.35 0.387 0.279 0.285 0.168 7 Radioactive Materials Handling Facility Leach Field 7-00255 70463 GEL 0.864 0.387 0.368 0.172 0.217 7 Radioactive Materials Handling Facility Leach Field 2.31 J 7-00258 70467 GEL 0.502 0.387 0.296 0.118 0.18 8-North Empire State Atomic Development Association 8N-00006 40011 GEL 0.535 0.387 0.195 0.0966 0.116 8-North Empire State Atomic Development Association 8N-00014 40027 GEL 0.957 0.387 0.145 0.124 0.0846 8-North Empire State Atomic Development Association 8N-00029 40057 GEL 1.41 0.387 0.263 0.187 0.158 8-North Empire State Atomic Development Association 8N-00035 40069 GEL 1.08 0.387 0.208 0.144 0.125 8-North Empire State Atomic Development Association 8N-00036 40071 GEL 0.449 0.387 0.19 0.0848 0.116 8-North Empire State Atomic Development Association 8N-00039 40077 GEL 2.34 J 0.387 0.19 0.263 0.111 8-North Building 4009 Leach Field 8N-00096 40177 GEL 1.26 0.387 0.177 0.159 0.104 8-North Building 4009 Leach Field 8N-00097 40179 GEL 0.64 0.387 0.155 0.0987 0.0907 Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 10 of 11 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 4.2 Surface Soil Analytical Results Exceeding Field Actions Levels Subarea Key Locations/Facilities Location Sample ID Analyzing Laboratory Activity FAL MDC TPU Critical Level Strontium-90 (Continued) 8-North Building 4009 8N-00110 40197 GEL 0.433 0.387 0.145 0.0785 0.0838 8-North Former Sodium Disposal Facility 8N-00122 40239 GEL 0.855 0.387 0.133 0.112 0.0777 8-South Subarea 8-South 8S-00012 40302 GEL 0.903 0.387 0.22 0.141 0.127 8-South Subarea 8-South 8S-00022 40322 GEL 1.53 0.387 0.211 0.192 0.124 8-South Subarea 8-South 8S-00031 40419 GEL 0.606 0.387 0.355 0.139 0.218 8-South Subarea 8-South 8S-00044 40432 GEL 0.447 0.387 0.419 0.146 0.255 NBZ Northern Buffer Zone West EPASED02 EPASED02 TAL 0.01 J 0.0750 0.078 0.026 0.044 NBZ Northern Buffer Zone West EPASED13 EPASED13 TAL 0.106 J 0.0750 0.06 0.021 0.034 NBZ Northern Buffer Zone East EPASED20 EPASED20 TAL 0.075 J 0.0750 0.068 0.022 0.038 NBZ Northern Buffer Zone West EPASED47 EPASED47S GEL 0.886 0.387 0.293 0.149 0.177 NBZ Northern Buffer Zone West NBZ-00013 90018 GEL 0.978 0.387 0.279 0.151 0.17 NBZ Northern Buffer Zone West NBZ-00090 90143 GEL 0.527 0.387 0.154 0.09 0.0888 NBZ Northern Buffer Zone West NBZ-00173 90231 GEL 0.873 0.387 0.228 0.136 0.135 NBZ Northern Buffer Zone West NBZ-00176 90234 GEL 0.417 0.387 0.221 0.0924 0.133 NBZ Northern Buffer Zone West NBZ-00180 90238 GEL 0.924 0.387 0.173 0.127 0.103 Notes: Refer to Table 2.1 of the Final Field Sampling Plan for Soil Sampling (HGL, 2012d) for a definition of radionuclide symbols. Reporting units in picocuries per gram. FAL - field action level GEL - GEL Laboratories LLC ID - identification MDC - minimum detectable concentration NBZ - Northern Buffer Zone TAL - TestAmerica Laboratories, Inc. TPU - total propagated uncertainty J - The analyte was detected at the reported concentration; the quantitation is an estimate. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 11 of 11 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 4.3 Subsurface Soil Analytical Results Exceeding Field Actions Levels Subarea Key Locations/Facilities Location ID Sample ID Analyzing Laboratory Activity FAL MDC TPU Critical Level Americium-241 5D-North 8-North Former Buildings 4173/4865 Former Sodium Disposal Facility 5DN-00161 50321 GEL 0.0589 0.0410 0.0274 0.0141 0.0111 8N-00059 40112 GEL 0.0484 0.0410 0.0162 0.0108 0.00573 90087 GEL 0.0647 0.0466 0.0374 0.0156 0.0169 Curium-243/244 NBZ Northern Buffer Zone East NBZ-00051 Cobalt-60 5B Former Building 4356 5B-00055 20139 TAL 0.0228 K 0.0228 0.011 0.0057 0.0052 5C Building 4100 5C-00074 10110 TAL 0.0247 0.0228 0.012 0.0061 0.0057 Cesium-137 6 Sodium Reactor Experiment Pond Area 6-00030 60042 GEL 0.554 0.193 0.0193 0.0326 0.00938 6 Sodium Reactor Experiment Pond Area 6-00034 60047 GEL 1.21 0.193 0.0156 0.0677 0.00757 6 Sodium Reactor Experiment Pond Area 6-00045 60065 GEL 0.475 0.193 0.0181 0.0281 0.0088 6 Liquid and Gas Radioactive Storage Tanks Area 6-00127 60177 GEL 0.194 0.193 0.0118 0.012 0.00577 6 Liquid and Gas Radioactive Storage Tanks Area 6-00142 60200 GEL 0.548 0.193 0.0122 0.0303 0.00597 6 Sodium Reactor Experiment Complex 6-00291 60449 GEL 1.47 0.193 0.0154 0.08 0.00751 6 Liquid and Gas Radioactive Storage Tanks Area 6-00293 60453 GEL 1.19 0.193 0.0116 0.063 0.00571 6 Fuel Element Storage Facility 6-00306 60540 GEL 74.9 0.193 0.0275 3.91 0.0136 6 Sodium Reactor Experiment Complex 6-00343 60589 GEL 0.308 0.193 0.0181 0.0194 0.00881 6 Old Conservation Yard 6-00416 60735 GEL 0.345 0.193 0.0231 0.0237 0.0112 6 Sodium Reactor Experiment Pond Area EPASED51 EPASED51B GEL 0.233 0.193 0.0142 0.0146 0.00687 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00002 70004 GEL 0.432 0.193 0.0199 0.0273 0.00968 7 Radioactive Materials Handling Facility 7-00007 70014 GEL 0.407 0.193 0.0145 0.0237 0.00702 7 Radioactive Materials Handling Facility 7-00008 70016 GEL 0.359 0.193 0.0148 0.0215 0.00722 7 Radioactive Materials Handling Facility Leach Field 7-00010 70020 GEL 0.524 0.193 0.0136 0.0298 0.00661 7 Radioactive Materials Handling Facility Leach Field 7-00016 70032 GEL 1.71 0.193 0.021 0.0935 0.0102 7 Radioactive Materials Handling Facility 7-00017 70034 GEL 0.389 0.193 0.0128 0.022 0.00623 7 Radioactive Materials Handling Facility 7-00021 70042 GEL 0.207 0.193 0.0183 0.0142 0.00887 7 Interim Storage Facility - Former Building 4654 7-00026 70052 GEL 0.227 0.193 0.0173 0.0148 0.00844 7 Interim Storage Facility - Former Building 4654 7-00030 70060 GEL 0.211 0.193 0.0152 0.0133 0.00742 7 Radioactive Materials Handling Facility 7-00053 70106 GEL 0.214 0.193 0.0159 0.0143 0.00777 7 Radioactive Materials Handling Facility Leach Field 7-00066 70122 GEL 0.334 0.193 0.0193 0.0208 0.00939 7 Interim Storage Facility - Former Building 4654 7-00078 70143 GEL 0.266 0.193 0.0165 0.0164 0.00804 7 Radioactive Materials Handling Facility 7-00086 70154 GEL 0.364 0.193 0.0148 0.0216 0.00719 7 Radioactive Materials Handling Facility 7-00087 70156 GEL 2.15 0.193 0.0188 0.117 0.00917 7 Radioactive Materials Handling Facility 7-00090 70162 GEL 0.492 0.193 0.0197 0.0304 0.00957 Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 1 of 4 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 4.3 Subsurface Soil Analytical Results Exceeding Field Actions Levels Subarea Key Locations/Facilities Location ID Sample ID Analyzing Laboratory FAL MDC TPU Critical Level 2.68 0.193 0.016 0.142 0.00782 Activity Cesium-137 (Continued) 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00130 70220 GEL 7 Radioactive Materials Handling Facility Leach Field 7-00139 70237 GEL 2.64 0.193 0.0196 0.14 0.00954 7 Radioactive Materials Handling Facility Leach Field 7-00140 70239 GEL 0.283 0.193 0.0179 0.0182 0.00875 7 Radioactive Materials Handling Facility 7-00157 70264 GEL 0.232 0.193 0.017 0.0159 0.00828 7 Interim Storage Facility - Former Building 4654 7-00225 70395 GEL 0.209 0.193 0.0191 0.0144 0.0093 7 Radioactive Materials Handling Facility Leach Field 7-00251 70457 GEL 1.51 0.193 0.0165 0.0815 0.00801 7 Radioactive Materials Handling Facility Leach Field 7-00252 70459 GEL 0.991 0.193 0.0183 0.055 0.00892 7 Radioactive Materials Handling Facility Leach Field 7-00253 70461 GEL 0.432 0.193 0.0203 0.0266 0.00991 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00269 70381 GEL 0.219 0.193 0.0164 0.0152 0.00798 Europium-152 5B Former Building 4010 5B-00326 20691 TAL 0.049 0.0459 0.03 0.012 0.015 5B Former Building 4010 5B-00332 20702 TAL 0.0544 0.0459 0.02 0.0083 0.0097 20691 TAL 7.38 7.380 0.18 0.34 0.09 30020 GEL 23.9 7.24 5.48 2.97 2.57 Tritium 5B Former Building 4010 5B-00326 Nickel-59 5A Former Building 4023 5A-00008 Plutonium-239/240 5D-North 7 Former Building 4353 Shield Test Irradiation Reactor - Former Building 4028 5DN-00146 50292 GEL 0.0526 0.0369 0.0268 0.0132 0.0108 7-00186 70322 GEL 0.187 0.0369 0.00502 0.021 0 8-North Former Sodium Disposal Facility 8N-00059 40112 GEL 0.0873 0.0369 0.0126 0.014 0.00389 8-North 4056 Landfill 8N-00120 40236 GEL 0.0713 0.0369 0.018 0.013 0.00681 Strontium-90 3-00005 80007 GEL 0.444 0.387 0.315 0.123 0.185 5A 3 Southern California Edison Substation Former Building 4093 (L85 Nuclear Experimentation Reactor) 5A-00159 30115 GEL 0.579 0.387 0.142 0.0909 0.0823 5A Former Building 4093 (L85 Nuclear Experimentation Reactor) 5A-00168 30124 GEL 2.56 J 0.387 0.162 0.272 0.0954 5B Building 4019 5B-00028 20049 TAL 0.09 0.0750 0.042 0.015 0.024 5B Building 4011 5B-00158 20351 TAL 0.117 0.0750 0.026 0.012 0.015 5D-North Hot Lab - Former Building 4020 5DN-00017 50033 GEL 0.49 0.387 0.321 0.125 0.193 5D-North Hot Lab - Former Building 4020 5DN-00025 50054 GEL 0.486 0.387 0.246 0.109 0.146 5D-North Hot Lab - Former Building 4020 5DN-00027 50059 GEL 0.654 0.387 0.199 0.112 0.119 5D-North Hot Lab - Former Building 4020 5DN-00041 50094 GEL 1 0.387 0.32 0.175 0.187 5D-North Hot Lab - Former Building 4020 5DN-00044 50100 GEL 0.41 0.387 0.23 0.0989 0.136 5D-North Hot Lab - Former Building 4020 5DN-00045 50103 GEL 1.4 0.387 0.189 0.174 0.111 5D-North Hot Lab - Former Building 4020 5DN-00073 50152 GEL 0.662 0.387 0.239 0.124 0.143 Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 2 of 4 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 4.3 Subsurface Soil Analytical Results Exceeding Field Actions Levels Subarea Key Locations/Facilities Location ID Sample ID Analyzing Laboratory FAL MDC TPU Critical Level 0.545 0.387 0.189 0.1 0.11 Activity Strontium-90 (Continued) 5D-North Former Building 4875 5DN-00117 50235 GEL 5D-North Former Building 4375 5DN-00120 50241 GEL 1.43 0.387 0.187 0.177 0.11 5D-North Pond Dredge Area 5DN-00194 50384 GEL 0.487 0.387 0.323 0.125 0.2 5D-North Hot Lab - Former Building 4020 5DN-00230 50563 GEL 0.579 0.387 0.304 0.132 0.178 5D-South Subarea 5D-South 5DS-00021 50481 GEL 0.43 0.387 0.292 0.116 0.17 5D-South Subarea 5D-South 5DS-00039 50511 GEL 0.43 0.387 0.292 0.117 0.169 6 Sodium Reactor Experiment Pond Area 6-00034 60047 GEL 0.641 0.387 0.233 0.115 0.139 6 Liquid and Gas Radioactive Storage Tanks Area 6-00142 60200 GEL 0.934 0.387 0.119 0.104 0.0721 6 Sodium Reactor Experiment Complex 6-00291 60449 GEL 0.405 0.387 0.188 0.0889 0.107 6 Fuel Element Storage Facility 6-00306 60540 GEL 0.882 0.387 0.607 0.23 0.368 6 Sodium Reactor Experiment Pond Area EPASED52 EPASED52B GEL 0.698 0.387 0.344 0.142 0.212 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00003 70006 GEL 3.57 0.387 0.101 0.351 0.059 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00005 70010 GEL 1.69 0.387 0.177 0.199 0.103 7 Radioactive Materials Handling Facility Leach Field 7-00016 70032 GEL 2.22 J 0.387 0.281 0.261 0.17 7 Interim Storage Facility - Former Building 4654 7-00026 70052 GEL 0.712 0.387 0.172 0.106 0.102 7 Interim Storage Facility - Former Building 4654 7-00039 70078 GEL 1.36 0.387 0.185 0.171 0.108 7 Shield Test Irradiation Reactor - Former Building 4028 7-00042 70104 GEL 3.24 0.387 0.1 0.32 0.0584 7 Radioactive Materials Handling Facility Leach Field 7-00056 70110 GEL 0.83 0.387 0.354 0.161 0.213 7 Radioactive Materials Handling Facility Leach Field 7-00057 70111 GEL 0.489 0.387 0.299 0.117 0.182 7 Subarea 7 Northern Panhandle 7-00070 70130 GEL 0.782 0.387 0.246 0.127 0.155 7 Interim Storage Facility - Former Building 4654 7-00074 70136 GEL 0.422 0.387 0.207 0.0928 0.12 7 Radioactive Materials Handling Facility 7-00083 70149 GEL 0.504 0.387 0.354 0.13 0.219 7 Shield Test Irradiation Reactor - Former Building 4028 7-00108 70191 GEL 0.524 0.387 0.162 0.0905 0.0966 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00116 70199 GEL 0.44 0.387 0.309 0.12 0.182 7 7 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin Southwest corner of Subarea 7 - North of Building 4019 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00117 7-00120 7-00135 70200 70205 70229 GEL GEL GEL 0.833 0.517 3.55 J 0.387 0.387 0.387 0.415 0.443 0.175 0.172 0.157 0.368 0.254 0.271 0.102 7 Radioactive Materials Handling Facility Leach Field 7-00139 70237 GEL 3.36 J 0.387 0.285 0.369 0.17 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00173 70282 GEL 0.929 0.387 0.258 0.144 0.16 7 Radioactive Materials Handling Facility Leach Field 7-00174 70283 GEL 1.3 0.387 0.331 0.195 0.205 7 Radioactive Materials Handling Facility Leach Field 7-00241 70446 GEL 0.719 0.387 0.338 0.147 0.204 7 Radioactive Materials Handling Facility Leach Field 7-00242 70447 GEL 0.525 0.387 0.399 0.145 0.246 7 Radioactive Materials Handling Facility Leach Field 7-00245 70449 GEL 1.09 0.387 0.33 0.185 0.194 7 Radioactive Materials Handling Facility Leach Field 7-00251 70457 GEL 9.26 0.387 0.143 0.89 0.0811 7 Radioactive Materials Handling Facility Leach Field 7-00252 70459 GEL 5.65 0.387 0.202 0.566 0.117 Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 3 of 4 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 4.3 Subsurface Soil Analytical Results Exceeding Field Actions Levels Subarea Key Locations/Facilities Location ID Sample ID Analyzing Laboratory Activity FAL MDC TPU Critical Level Strontium-90 (Continued) 7 Radioactive Materials Handling Facility Leach Field 7-00253 70461 GEL 0.9 0.387 0.356 0.17 0.212 7 Radioactive Materials Handling Facility Site 4614 Holdup Pond/Catch Basin 7-00275 70420 GEL 0.471 0.387 0.209 0.0972 0.123 7 Southwest corner of Subarea 7 - North of Building 4019 7-00296 70495 GEL 0.618 0.387 0.244 0.114 0.147 7 Outfall 3 OF03-003 0F03-003-SB-39-H TAL 0.397 0.0750 0.042 0.026 0.024 8-North Empire State Atomic Development Association 8N-00003 40006 GEL 0.584 0.387 0.316 0.13 0.197 8-North Empire State Atomic Development Association 8N-00015 40030 GEL 0.51 0.387 0.388 0.141 0.246 8-North Empire State Atomic Development Association 8N-00028 40056 GEL 2.51 J 0.387 0.12 0.256 0.0707 8-North Empire State Atomic Development Association 8N-00050 40092 GEL 1.01 0.387 0.143 0.128 0.0843 8-North Former Sodium Disposal Facility 8N-00055 40104 GEL 2.71 J 0.387 0.178 0.29 0.105 8-North Former Sodium Disposal Facility 8N-00084 40161 GEL 0.387 0.135 0.127 0.0779 0.995 8-North Building 4009 Leach Field 8N-00100 40185 GEL 1.26 0.387 0.169 0.157 0.0994 8-North Building 4009 8N-00105 40192 GEL 1.39 0.387 0.156 0.165 0.0917 8-North Building 4100 8N-00129 40201 GEL 0.534 0.387 0.139 0.0858 0.0808 8-North Empire State Atomic Development Association 8N-00205 40393 GEL 0.628 0.387 0.493 0.173 0.304 8-South Subarea 8-South 8S-00011 40301 GEL 1.5 0.387 0.238 0.196 0.14 8-South Subarea 8-South 8S-00013 40305 GEL 0.4 0.387 0.202 0.0906 0.116 8-South Subarea 8-South 8S-00023 40325 GEL 0.873 0.387 0.282 0.155 0.164 NBZ Northern Buffer Zone West NBZ-00032 90057 GEL 0.725 0.387 0.172 0.103 0.105 NBZ Northern Buffer Zone West NBZ-00083 90130 GEL 0.586 0.387 0.196 0.1 0.118 Notes: Refer to Table 2.1 of the Final Field Sampling Plan for Soil Sampling (HGL, 2012d) for a definition of radionuclide symbols. Reporting units in picocuries per gram. FAL - field action level GEL - GEL Laboratories LLC ID - identification MDC - minimum detectable concentration NBZ - Northern Buffer Zone TAL - TestAmerica Laboratories, Inc. TPU - total propagated uncertainty J - The analyte was detected at the reported concentration; the quantitation is an estimate. K - Analyte present. Reported value may be biased high. Actual value is expected to be lower. Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 4 of 4 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 5.1 Radiological Areas of Interest Radionuclides Detected at Concentrations Equal to or Greater than FAL Surface Soil Key Subarea Location/Facility Subsurface Soil Number of Radionuclides Number of Surface Soil Sample Concentration Range Subsurface Detected Surface Soil (pCi/g) Soil Samples Samples Operational History Subsurface Soil Sample Concentration Range (pCi/g) Radioactive Materials Handling Facility Complex Radioactive Materials Handling Facility (RMHF) RMHF Site 4614 Holdup Pond/Catch Basin RMHF Leach Field 7 7 7 The RMHF was a support facility to the SNAP program, the SRE, and the Hallam Nuclear Power Facility. It was designed to handle the storage, volume reduction, packaging, and shipping of the SNAP and SRE radioactive waste. In general, radioactive wastes handled at the RMHF were residues from chemical and metallurgical laboratory operations, spent reactor fuel decladding operations, maintenance work on contaminated equipment, and decontamination and decommissioning of facilities in which nuclear operations were previously conducted. The RMHF received radioactive water from the Hot Lab, the SRE, and any other DOE facilities that generated radioactive water as a part of operations. The RMHF 4614 Holdup Pond/Catch Basin Site area, formerly the Radioactive Material Disposal Facility 4614 Site area, comprises RMHF 4614 Holdup Pond/Catch Basin and the drainage channel that terminates at the pond from the west side of the RMHF complex. The RMHF 4614 Holdup Pond/Catch Basin is often referred to as the Building 4028 Pond or 4028 Pond, and has also been referred to as the RD-621 pond. For purposes of this section, Site 4614 will be referred to as the RMHF 4614 Holdup Pond. The RMHF 4614 Holdup Pond was originally constructed in the early to mid-1960s as a holdup pond for Building 4028. Located approximately 100 feet to the northeast of the RMHF, the leach field was used from early 1959 through late 1961 for the disposal of sanitary waste associated with Building 4021. In late 1961, a central sanitary sewer system was constructed at the SSFL and Building 4021 was connected to it. RMHF sanitary waste was subsequently accepted at the Area III sewage treatment plant. The RMHF septic system was abandoned in place. Cs-137 34 0.202 - 19.8 9 0.207 - 2.15 Pu-239/240 1 0.0475 0 NA Co-60 1 0.0264 0 NA Sr-90 5 0.491 - 1.19 1 0.504 Cs-137 25 0.195 – 2.5 3 0.219 – 2.68 Pu-239/240 1 0.0702 0 NA Sr-90 1 1.64 7 0.44 – 3.57 Cs-137 27 0.199 – 4.7 8 0.283 – 2.64 Sr-90 16 0.392 – 14.3 11 0.489 – 9.26 Cs-137 21 0.256 – 24.3 2 0.308 – 1.47 Pu-239/240 1 0.0515 0 NA Co-60 1 0.048 0 NA Sr-90 3 0.392 – 21.3 1 0.405 Sodium Reactor Experiment Complex Sodium Reactor Experiment (SRE) Complex Santa Susana Field Laboratory Radiological Characterization of Soils 6 The area comprises Building 4143, concrete pads Nos. 4413, 4894, 4895, 4896, 4897, and 4898, electrical substation Building 4683, and the land surrounding these facilities located at the end of E Street. Building 4143 was constructed between April 1955 and February 1957 and was operated as a nuclear reactor until February 1964. Building 4143 housed a high-temperature reactor with a slightly enriched uranium metal fuel (Core I) and sodium-cooled, hexagonal zirconium clad graphite moderator elements. After an accident in 1959, the enriched uranium fuel was replaced with a 93 percent uraniumthorium metal alloy fuel (Core II). The SRE was developed to demonstrate a sodiumcooled, graphite–moderated reactor for civilian use. U.S. EPA Region 9 1 of 10 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 5.1 Radiological Areas of Interest Radionuclides Detected at Concentrations Equal to or Greater than FAL Surface Soil Key Subarea Location/Facility Subsurface Soil Number of Radionuclides Number of Surface Soil Sample Concentration Range Subsurface Detected Surface Soil (pCi/g) Soil Samples Samples Operational History Subsurface Soil Sample Concentration Range (pCi/g) Sodium Reactor Experiment Complex (Continued) SRE Pond Area 6 The SRE pond area (Site 4773) was constructed in 1956 as a retention pond and dam for the SRE. The pond was originally designed for natural seepage and evaporation to control the seasonal water level and provide capacity for winter storm water collection. After 1964, storm water runoff was the only source of water to the SRE pond. The SRE Pond is still in existence and contains surface water runoff from the SRE Complex during the wet season. Cs-137 5 0.198 – 0.389 4 0.233 – 1.21 Pu-239/240 1 0.0302 0 NA Sr-90 2 0.185 - 0.617 2 0.641 – 0.698 Also known as Building 4653 area, an interim radioactive waste vault that stored liquid wastes generated from the SRE. Most of the radioactivity was from mixed fission products. Cs-137 22 0.22 – 46.4 3 0.194 - 1.19 Sr-90 5 0.523 – 2.39 1 0.934 Cs-137 8 0.307 – 2.45 0 NA Pu-239/240 1 0.038 0 NA Cs-137 11 0.199 – 20.2 0 NA Sr-90 6 0.647 – 4.2 1 0.782 Cs-137 27 0.229 – 2.53 0 NA Sr-90 1 0.43 0 NA Cs-137 7 0.249 – 1.81 4 0.209 – 0.266 Sr-90 4 0.435 - 0.93 3 0.422 – 1.36 SRE Liquid and Gas Radioactive Storage Tanks Area 6 SRE Hot Oil Sodium Cleaning Facility 6 Also known as Building 4724. Designed for cleaning sodium, in a hot oil bath, from large pipes and assemblies from the secondary loop of the SRE. Subarea 7 Northern Panhandle 7 Located in the northeast portion of Subarea 7. The photo interpretation showed “Cleared Area” but no other feature or process was noted in the HSA. 7 The HWMF began operation in 1978 as a drum storage yard, and by 1983 was a fully permitted RCRA hazardous waste treatment and storage facility for non-radiological chemical wastes generated on site. In 1997, the HWMF was deactivated and all operations ceased. Hazardous Waste Management Facility (HWMF) Interim Storage Facility Santa Susana Field Laboratory Radiological Characterization of Soils 7 The Interim Storage Facility (Building 4654) was originally used to store dummy and spent fuel elements, shipping and storage casks, and hot waste generated at the SRE. After the SRE stopped operating, it was also used to store waste from the OMR Experiment and the SNAP. It was taken out of service in 1964 and did not support an active program from 1964 through 1984. Because low-level radiation was released from the storage of containers at this facility it was kept in surveillance and maintenance mode to contain the contamination until decommissioning began in 1984. U.S. EPA Region 9 2 of 10 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 5.1 Radiological Areas of Interest Radionuclides Detected at Concentrations Equal to or Greater than FAL Key Subarea Location/Facility 17th Street Drainage New Conservation Yard Fuel Element Storage Facility Former Building 4010 Hot Lab - Former Building 4020 Former Sodium Disposal Facility Santa Susana Field Laboratory Radiological Characterization of Soils Surface Soil Subsurface Soil Number of Radionuclides Number of Surface Soil Sample Concentration Range Subsurface Detected Surface Soil (pCi/g) Soil Samples Samples Operational History Subsurface Soil Sample Concentration Range (pCi/g) 5B The 17th Street Drainage is located south of the intersection of G and 17th streets. This area is the site of a storm water channel where a berm was constructed in 1962, permitting the area to serve as a retention pond collecting drainage from upgradient areas in Subareas 5B, 5A, and 7. The former pond measured approximately 30 feet by 30 feet. In 1999 the main drainage system was rerouted along the north side of G Street. Cs-137 12 0.213 -0.911 0 NA 6 Site 4583-New was developed as the new salvage yard after the ESG salvage yard was closed in 1977. All salvageable, non-radioactive materials were moved to the site in and after 1977. Items included used equipment and drums. In 1988, the site was cluttered with items of large metal equipment and scrap metal. Cs-137 12 0.21 – 4.61 0 NA Cs-137 13 0.219 – 196 1 74.9 6 Comprises Building 4064, mechanical equipment slab Site 4864, an extensive side yard, and the land surrounding these areas located on G Street. Building 4064, built in 1958, was the source and special nuclear material storage facility. It was used for storing packaged items of source material (natural uranium, depleted uranium, thorium) and special nuclear materials (enriched uranium, plutonium, and U-233) of various forms and configurations. The facility was demolished in 1997 together with the removal of a septic tank and leach field. Sr-90 1 0.557 1 0.882 Cs-137 2 0.282 - 0.254 0 NA Sr-90 1 0.563 0 NA Eu-152 1 0.078 2 0.049 – 0.0544 H-3 0 NA 1 7.38 Cm-243/244 1 0.0178 0 NA Constructed in 1959, Building 4020, formerly the Component Development Hot Cell, was constructed for the remote handling and examination of highly radioactive materials. The building was completely demolished between 1995 and 1996, and the site was backfilled in 1997. Cs-137 1 1.42 0 NA Sr-90 6 0.408 – 0.821 8 0.41 - 1.4 Also known as Site 4886 or Sodium Burn Pit, this facility comprised approximately 2 acres located on the north side of the westernmost end of H Street. It operated as the Sodium Disposal Facility, from 1956 until 1978. It was used extensively during the 1960 to 1970 period for the disposal of combustible materials such as kerosene, Na, and NaK from scrap test components such as pumps, valves, etc., from the SRE, SNAP, and other nuclear program operations. Cs-137 2 0.197 - 0.205 0 NA Am-241 1 0.0514 1 0.0484 Sr-90 1 0.855 2 0.995 – 2.71 Pu-239/240 0 NA 1 0.0873 5B 5D 8 Building 4010 housed the SNAP Experiment Reactor, also known as the SNAP 2 Experimental Reactor, which was a prototype for the basic SNAP reactor and used for power demonstration and endurance tests. The SNAP Experiment Reactor/SNAP 2 Experimental Reactor operated in Building 4010 from September 1959 to December 1960. The building was demolished in 1978. U.S. EPA Region 9 3 of 10 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 5.1 Radiological Areas of Interest Radionuclides Detected at Concentrations Equal to or Greater than FAL Key Subarea Location/Facility Surface Soil Subsurface Soil Number of Radionuclides Number of Surface Soil Sample Concentration Range Subsurface Detected Surface Soil (pCi/g) Soil Samples Samples Operational History Subsurface Soil Sample Concentration Range (pCi/g) 6 Comprises Building 4003, substation Building 4693, support Building 4825, and the land surrounding these three buildings located near the end of E Street. Building 4003 contained two radioactive waste sinks connected to 5-gallon bottles, and a highly shielded area designed for remote manipulation of radioactive materials, known as the Hot Cave. Building 4003 was used to assemble fuel elements for the SRE from 1957 through 1964. Uranium and thorium metal slugs were loaded into metal tubes, the remaining tube space was filled with sodium and the tubes were sealed. Fuel elements for three SRE cores were prepared in Building 4003, but only two cores were used. The third core was shipped offsite. The Hot Cave was designed and constructed to investigate the chemistry of molten uranium, and to study the separation of fission products and plutonium from uranium systems. Cs-137 4 0.197 – 0.241 0 NA 5A Constructed in 1955, Building 4073 served as the KEWB reactor building and consisted of an underground concrete structure and an above-ground wood and metal changing/workroom. The KEWB reactor was a small graphite-encased research reactor that used a water solution of uranyl sulfate as fuel. Operations in the building halted in November 1966. Sr-90 1 0.091 0 NA Old Conservation Yard 6 Also known as Site 4583-Old, it incorporated a barrel storage yard and excess salvageable items were stored in the area. In 1969, the barrel storage yard was converted to a material storage area. The ESG salvage yard was used extensively during the 1960s and 1970s before it was closed in 1977 and cleared of materials. Cs-137 2 0.201 - 3.42 1 0.345 Subarea 8-South 8 No operational history has been identified for this area. Cs-137 4 0.212 - 0.726 0 NA Sr-90 4 0.447 – 1.53 3 0.4 – 1.5 Cs-137 6 0.196 – 0.314 0 NA Eu-154 1 0.136 0 NA Sr-90 1 0.448 2 0.43 - 0.43 Pu-239/240 1 0.0502 0 NA Sr-90 0 NA 1 0.444 Sr-90 1 0.648 0 NA Am-241 0 NA 1 0.589 Former Building 4003 Engineering Test Building Kinetic Experiment Water Boiler (KEWB) Subarea 5D South 5D Southern California Edison Substation 3 Former Buildings 4173/4865 5D Santa Susana Field Laboratory Radiological Characterization of Soils No operational history has been identified for this area. Constructed about 1956 and currently delivers power to SSFL via two overhead highvoltage transmission lines. The site borders the Old Salvage Yard. Designed for use as a sodium storage pad. U.S. EPA Region 9 4 of 10 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 5.1 Radiological Areas of Interest Radionuclides Detected at Concentrations Equal to or Greater than FAL Key Subarea Location/Facility Former Shield Test Irradiation Reactor (STIR) Building 4028 Heavy Metal Likely Chemical Remediation Zone (LCRZ) Building 4100 Building 4015 Santa Susana Field Laboratory Radiological Characterization of Soils 7 5A Surface Soil Number of Radionuclides Number of Surface Soil Sample Concentration Range Subsurface Detected Surface Soil (pCi/g) Soil Samples Samples Operational History The building was originally constructed to house a water-cooled, zirconium-hydride moderated reactor, used to perform tests on space reactor shields using a fission plate driven by neutrons from the thermal column of the swimming pool-type reactor. The STIR was fueled with uranium-aluminum alloy clad entirely with aluminum. The STIR was used for reactor physics experiments, studies in radiation damage to electronic and instrumentation components, and neutron radiography. Once testing with the STIR was finished, the fuel elements were removed and the pool water was drained in June 1973. This area was designated by DOE and DTSC as a LCRZ based on the elevated concentrations of heavy metals that were detected in soil samples collected from this area. Building 4100 housed the Advanced Epithermal Thorium Reactor, which was a separablehalf critical experiment operating at less than 200 watts (thermal), Fast Critical Experiment Laboratory, and Radiation Safety and Computed Tomography Laboratory. Twenty reactor core configurations were studied including thorium, uranium, and later, high-energy fast neutrons in the Fast Critical Experiment Laboratory. The Fast Critical 5C and 8N Experiment Laboratory operated until about 1974 under NRC License No. CX-17. The NRC terminated License No. CX-17, and released Building 4100 for unrestricted use in October 1980. From the late 1980s until 2008, the high bay was used for high energy Computer Aided Tomography. NASA owned the scanner. The laboratories were used for radioactive sample counting and instrument calibration. 5C Subsurface Soil Building 4015 was used to store construction materials, currently it is empty.  There is no evidence of radiological burial or disposal in the Building 4015 area. A debris disposal area was identified in the northeast region of the Building 4015 area, south of the intermittent stream. The Building 4373 leach field is a potential source of radiological contamination that may have migrated onto the Building 4015 site. U.S. EPA Region 9 5 of 10 Subsurface Soil Sample Concentration Range (pCi/g) Pu-239/240 0 NA 1 0.187 Sr-90 0 NA 2 0.524 – 3.24 Cs-137 2 0.24 – 0.327 0 NA Cs-137 2 0.316 - 0.818 0 NA Pu-239/240 1 0.0233 0 NA Sr-90 0 NA 1 0.534 Co-60 0 NA 1 0.0247 Pu-239/240 1 0.0487 0 NA HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 5.1 Radiological Areas of Interest Radionuclides Detected at Concentrations Equal to or Greater than FAL Key Subarea Location/Facility Surface Soil Number of Radionuclides Number of Surface Soil Sample Concentration Range Subsurface Detected Surface Soil (pCi/g) Soil Samples Samples Operational History Building 4863 is first identified in 1972 Atomic International industrial planning maps as a hydraulic test loop building. The Hydraulic Test Facility was used to conduct preliminary tests on piping, pumps and other loop components. The test facility used water because it has a similar flow rate to liquid sodium. The tests were designed so the researchers could examine descriptors such as fatigue rates and results such as fracturing of components. Building 4863 served as the experimental test loop. According to a 1992 NEPA compliance activities status report included in the 1992 annual site environmental report, Building 4863 was placed on “inactive standby facility maintenance” on September 29, 1992. Building 4863 was demolished in 2003. Former Building 4353 5D Empire State Atomic Development Association 8 Used for testing pipe bursting characteristics under sodium-water reaction conditions. 8 Used as a landfill for the disposal of loose fill of earth, bedrock, and minor construction debris (asphalt, concrete, scrap metal, etc) from building construction until the early 1970s. After this time, North American Rockwell used the site as a temporary storage location for hazardous and non-hazardous waste materials. In the late 1970s, all items from the landfill and ravine were removed. In 1999, the pit was drained to eliminate the recharge potential to groundwater. 4056 Landfill Building 4005 Santa Susana Field Laboratory Radiological Characterization of Soils 5A Subsurface Soil Building 4005 was constructed in 1958 for non-nuclear testing of thermodynamic characteristics of proposed coolants for the OMR Experiment and Piqua reactors. During the mid 1960s, Building 4005 was converted into a small-scale production facility, the Uranium Carbide Fuel facility, to study the operations associated with manufacturing reactor fuel assemblies out of uranium carbide. The facility operated for a period of nine months during 1966 and1967, first using depleted uranium, and later enriched uranium and was a radiological controlled access area. Beginning in 1972, Building 4005 was used as the Molten Salt Test Facility, a non-nuclear test facility consisting of the Molten Salt Test Bed and the Process Demonstration Unit. According to the 1997 annual site environmental report, Building 4005 was demolished in 1997. U.S. EPA Region 9 6 of 10 Subsurface Soil Sample Concentration Range (pCi/g) Cs-137 1 0.194 0 NA Cs-137 1 0.206 0 NA Sr-90 6 0.449 – 2.34 5 0.51 – 2.51 Cs-137 1 0.878 0 NA Pu-239/240 0 NA 1 0.0713 Eu-152 2 0.073 – 0.165 0 NA HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 5.1 Radiological Areas of Interest Radionuclides Detected at Concentrations Equal to or Greater than FAL Key Subarea Location/Facility Subsurface Soil Number of Radionuclides Number of Surface Soil Sample Concentration Range Subsurface Detected Surface Soil (pCi/g) Soil Samples Samples Operational History Served as the Liquid Metals Component Test Building and the Corrosion Test Loop. The second section, constructed in 1976 and known as 23A, served as a storage and setup room as well as an analytical chemistry laboratory. In 1976, a use authorization allowed the use of a small section of activated stainless steel Experimental Boilers Reactor fuel cladding in a small sodium test loop, located in the northwest corner of Building 4023, to gather data on transport characteristics of radiological contamination in sodium loops. The sodium loop tests were halted in 1983 and the loop was dismantled in 1986. According to a 1987 Site Consolidation Assessment, Building 4023 served as a development and demonstration test facility in support of the Rocky Flats Plutonium Recovery Project in 1987. In 1989, reports appear to indicate that Building 4023 served as a support facility for the Transuranic Management by Pyropartitioning – Separation operations in Building 4020, located in Subarea 5D. Building 4023 was demolished in 1999. Subsurface Soil Sample Concentration Range (pCi/g) Pu-238 1 0.0137 0 NA Ni-59 0 NA 1 23.9 Pu-239/240 1 0.0323 0 NA Sr-90 0 NA 1 0.397 Operated as a non-nuclear sodium laboratory. Use Authorizations provided for minor uses of radioactive materials. Cooling Tower 4616 was removed in the early 1980s to make room for a Power Pak associated substation. Building 4006 closed operations in 1999. Sr-90 2 0.096 – 0.125 0 NA Contained the OMR and SGR critical facilities, which were pilot plants for developing large nuclear power plants for commercial power generation, such as the Hallam nuclear power plant in Nebraska and the Piqua nuclear power plant in Ohio. The OMR was used for testing uranium fueled reactors moderated and cooled by organic liquids. The SGR was used to determine the operating characteristics of reactors with cores cooled by 5D and 8N sodium and moderated with graphite. The OMR operated from 1959 to 1965 and the SGR operated from 1960 to 1967. In addition, as-built Drawing No. 303-009-E17 indicates that a Van de Graaff generator was installed in the SGR graphite storage area in August 1960 and was moved to Building 4030 in about May 1962. Following release for unrestricted use in 1999, Building 4009 was used for non-nuclear research and development, including laser research. Operations in Building 4009 ceased in mid-2007. Sr-90 2 0.433 - 1.55 1 1.39 Building 4023 5A Outfall 3 7 Building 4006 Building 4009 Surface Soil 5B Santa Susana Field Laboratory Radiological Characterization of Soils Outfall 3 is an NPDES permitted sampling point regulated by the Los Angeles RWQCB. The outfall is a specifically designed multimedia filtration system engineered to filter the surface water before it travels downgradient. In July 2010, Outfall 3 was undergoing maintenance and the filter pack and liner had been removed. six soil samples were collected before the new liner and filter pack was installed. U.S. EPA Region 9 7 of 10 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 5.1 Radiological Areas of Interest Radionuclides Detected at Concentrations Equal to or Greater than FAL Key Subarea Location/Facility Building 4009 Leach Field Former Building 4353 Surface Soil Subsurface Soil Number of Radionuclides Number of Surface Soil Sample Concentration Range Subsurface Detected Surface Soil (pCi/g) Soil Samples Samples Operational History 8 A leach field, used for the disposal of both sanitary and radioactive liquid wastes before the central sewage system was installed in 1961, was located approximately 50 feet north of Building 4009. It contained six leach lines ranging in length from 15 to 42 feet. The leach lines extended north from a 2,340-gallon septic tank that was located outside the northwestern portion of Building 4009. The leach field comprised 4-inch diameter terra cotta clay piping surrounded by large gravel and buried at depths ranging from 4 to 5 feet below ground surface. The leach field was reported to include approximately 300 linear feet of leach lines. 5D Information regarding the operations in Building 4353 is limited. The 1957-1958 progress report indicated the purpose of the building was to provide field test facilities for the performance of organic materials testing. A June 24, 1960, Atomics International technical data record indicated that an Advanced OMR Heat Transfer Loop was located at Building 4353 to obtain information on the fouling tendencies of organic coolants. The steel portion of the structure was removed in the late 1970s. Subsurface Soil Sample Concentration Range (pCi/g) Sr-90 2 0.64 – 1.26 1 1.26 Pu-239/240 0 NA 1 0.0526 Sr-90 3 0.422 – 1.27 0 NA Sr-90 1 0.52 0 NA Pu-238 1 0.0492 0 NA Sr-90 1 0.643 1 0.545 Former Building 4373 Leach Field 5D Used as the first SNAP critical facility where several critical experiments and tests on critical assemblies had been completed. The leach field for 4373 is located southeast of Building 4373 and was replaced with a sewage treatment system in 1960. Former Building 4875 5D Designed as a “creep loop tower” to support Building 4375. Building 4029 5A Originally constructed to store radioactive source materials for instrument calibration. Building 4029 was later incorporated into the HWMF. Cs-137 1 0.2 0 NA Building 4462 5C A multistory building used as the Sodium Pump Test Facility and tested pumps at high temperatures and pressures. Sr-90 1 0.098 0 NA Building 4055 5D Located outside the ETEC boundary and includes the Nuclear Material Development Facility and used for research, development, and production of nuclear fuels and radioactive sources. Sr-90 1 0.395 0 NA Southwest corner of Subarea 7 7 This area is directly north of Building 4019, located in Subarea 5B. Sr-90 0 NA 2 0.517 – 0.618 Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 8 of 10 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 5.1 Radiological Areas of Interest Radionuclides Detected at Concentrations Equal to or Greater than FAL Key Subarea Location/Facility Surface Soil Subsurface Soil Number of Radionuclides Number of Surface Soil Sample Concentration Range Subsurface Detected Surface Soil (pCi/g) Soil Samples Samples Operational History Subsurface Soil Sample Concentration Range (pCi/g) Former Building 4093 (L85 Reactor) 5A Constructed in 1958 to house the AE-6 Reactor designed to provide a thermal neutron source for evaluating neutron behavior in subcritical exponential-type assemblies, and for irradiating foils and other materials. In 1972, the reactor was renamed L-85 and operated as a commercial operation for central station power plant operator training and for neutron radiography inspection of precision forgings, castings, and electronic and explosive devices for manufacturing defects. Building 4011 5B Constructed in 1958 as an administration and services building, but later became the Radiation Instrument Calibration Laboratory used to repair and calibrate radiological instruments. Sr-90 0 NA 1 0.117 Building 4375 5D Building 4375 was a test shelter for testing SNAP control rod assemblies. Building 4375 was originally designed to perform creep tests on full-size OMR Piqua-type fuel elements. Sr-90 0 NA 1 1.43 5D Historical aerial photographs show excavation activities north of Building 4173(4865) in which no information has been located. RCRA Facility Investigation maps delineate this area as, "Pond Dredge". Sr-90 0 NA 1 0.487 Building 4019 5B Constructed in 1962 as the SNAP Flight Systems Nuclear Qualification Test Building to conduct criticality acceptance tests of SNAP reactors before they were delivered to the Atomic Energy Commission for launch as space power systems. Sr-90 0 NA 1 0.09 Former Building 4356 5B Constructed in 1959 as the Sodium Component Test Installation High Bay and was development test facility for liquid metal (sodium) system components. Co-60 0 NA 1 0.0228 Pond Dredge Area Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 9 of 10 Sr-90 0 NA 2 0.579 – 2.56 HydroGeoLogic, Inc. 12/21/2012 HGL— Radiological Characterization of Soils Area IV and the NBZ, SSFL—Ventura County, California Table 5.1 Radiological Areas of Interest Radionuclides Detected at Concentrations Equal to or Greater than FAL Key Subarea Location/Facility Surface Soil Subsurface Soil Number of Radionuclides Number of Surface Soil Sample Concentration Range Subsurface Detected Surface Soil (pCi/g) Soil Samples Samples Operational History The NBZ–northeast area comprises land and drainage channels located north of Area IV NBZextending west to east between the SRE complex and Area I. The NBZ is also Northeast commonly referred to as the Northern Undeveloped Land. The southeastern border of Northern Buffer Zone the NBZ-northeast adjoins both Subareas 3 and 6. In May 1997, Rockwell purchased the (NBZ) 175 acres, to form the NBZ, from the adjoining Brandeis-Bardin Institute, which had owned the land since 1947. Rockwell purchased this land because radioactive and NBZNorthwest chemical contamination originating from the SSFL had been found on the property by environmental contractors in the early 1990s. Subsurface Soil Sample Concentration Range (pCi/g) Cs-137 2 0.212 - 0.277 0 NA Cm-243/244 0 NA 1 0.0647 Sr-90 1 0.075 0 NA Cs-137 1 0.207 0 NA Sr-90 8 0.01 – 0.978 2 0.586 - 0.725 Pu-239/240 1 0.0384 0 NA Notes: Refer to Table 2.1 of the Final Field Sampling Plan for Soil Sampling (HGL, 2012d) for a definition of radionuclide symbols. DTSC - Department of Toxic Substance Control DOE - Department of Energy ESG - Energy Systems Group ETEC - Energy Technology Engineering Center FAL - Field Action Level HSA - Historical Site Assessment NA - not applicable NASA - National Aeronautical and Space Administration NEPA - National Environmental Policy Act NPDES - National Pollutant Discharge Elimination System NRC - Nuclear Regulatory Commission OMR - Organic Moderated Reactor pCi/g - picocuries per gram RCRA - Resource Conservation and Recovery Act RWQCB - Regional Water Quality Control Board SGR - Sodium Graphite Reactor SNAP - Systems for Nuclear Auxiliary Power SSFL - Santa Susana Field Laboratory Santa Susana Field Laboratory Radiological Characterization of Soils U.S. EPA Region 9 10 of 10 HydroGeoLogic, Inc. 12/21/2012 FIGURES This page was intentionally left blank. HGL—Radiological Characterization of Soils in Area IV and NBZ, SSFL—Ventura County, California Figure 1.1 Site Location Map Santa Susana Field Laboratory Northern Buffer Zone NASA U.S. EPA Region 9 AREA IV AREA II AREA I AREA III Legend Area IV Study Area Boundary Property Boundary Southern Buffer Zone Santa Susana Field Laboratory ³ 0 0 0.25 0.5 50 100 1 Miles Miles 200 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\ Fig1-1_SiteLocationMap.mxd 10/29/2012 pbillock Source: CaSil, NAIP 2009; Boeing 2008 HGL—Radiological Characterization of Soils in Area IV and NBZ, SSFL—Ventura County, California Figure 2.1 Adjacent Populated Areas Santa Susana Field Laboratory Moorpark Simi Valley U.S. EPA Region 9 Legend Chatsworth Area IV & Northern Buffer Zone Santa Susana Field Laboratory Area IV & Northern Buffer Zone Santa Susana Field Laboratory Bell Canyon Canoga Park Thousand Oaks Agoura Hills Calabasas ³ 0 4000 8000 Scale In Feet 16000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\ Fig2-1_AdjacentPopulatedAreas.mxd 10/29/2012 pbillock Source: Preliminary Geologic Map of the Los Angeles 30´ x 60´ Quadrangle, Southern California; Yerkes and Campbell; 2005 Coordinate System: NAD83 CA State Plane V HGL—Radiological Characterization of Soils in Area IV and NBZ, SSFL—Ventura County, California Figure 2.2 Area IV Subareas Santa Susana Field Laboratory U.S. EPA Region 9 Northern Buffer Zone East Legend Subarea 3 Area IV Subareas Subarea 6 Subarea 7 Northern Buffer Zone West Subarea 5A Subarea 5B Subarea 5C Subarea 8-North Subarea 5D-North Subarea 8-South Subarea 5D-South ³ 0 250 500 Scale In Feet 1,000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\ Fig2-2_AreaIV_Subareas.mxd 11/1/2012 pbillock Source: CIRGIS 2007; Boeing 2009 20 0 200 00 19 140 0 1600 16 00 1700 1300 1800 13 00 ³ 0 140 500 1000 2000 Scale In Feet 0 0 0 14 0 00 16 00 0 0 15 13 00 1600 16 00 1600 1700 1800 1800 17 0 1700 0 1600 1600 160 19 00 180 0 180 0 1800 1500 00 14 1600 00 19 170 0 00 19 00 0 15 0 18 00 190 0 0 180 00 17 00 00 0 1900 15 0 00 18 1200 1600 18 00 2000 00 19 17 2100 2000 00 00 19 1800 1700 1300 20 00 1500 18 00 13 0 200 19 00 0 00 170 0 Southern Buffer Zone 0 00 17 00 150 0 200 0 1700 14 0 00 0 170 16 0 20 50 ft Contours 1800 110 0 0 21 20 2000 2000 500 21 00 2000 00 Unlined Channel 15 0 20 0 0 2000 19 0 0 19 00 Lined Channel 22 00 1800 2000 Buildings 2000 200 0 18 00 Drainage Divide 00 20 AREA I 00 22 2100 AREA III 0 200 0 1500 1800 19 2000 1900 19 00 1500 1900 210 AREA II 20 00 Property Boundary Administrative Boundaries 0 210 00 Legend 00 19 18 00 AREA IV 0 2000 14 00 1600 1800 2 000 19 00 0 1800 18 00 0 170 U.S. EPA Region 9 1400 0 15 0 1400 00 16 1600 1300 1300 12 00 1100 12 00 16 0 00 0 NASA 1800 1 90 00 20 00 1800 18 1900 0 14 200 00 19 1900 00 21 00 0 00 2100 16 200 0 2000 1900 2 Figure 2.3 Topographic Map Santa Susana Field Laboratory 1800 0 17 00 13 00 15 1200 00 0 20 0 0 170 1800 00 16 1400 110 0 00 15 12 00 Northern Buffer Zone Northern Buffer Zone 16 00 19 00 1300 0 130 00 14 14 1600 2000 HGL—Radiological Characterization of Soils in Area IV and NBZ, SSFL—Ventura County, California Y:\Santa_Susana\EP9038\Soil_Sampling\Report\ Fig2-3_TopographicMap.mxd 10/29/2012 pbillock Source: CDM Inc. (2008). Draft Gap Analysis Report, Submitted on June 1, 2008. Prepared for the U.S. Department of Energy HGL—Radiological Characterization of Soils in Area IV and NBZ, SSFL—Ventura County, California Figure 2.4 Drainage Pathway Map Santa Susana Field Laboratory U.S. EPA Region 9 9 10 Legend 4 Outfall Approximate Drainage Pathways Intermitent Streams 3 6 AreaIV Subareas 7 5 17 18 0 0 400 N ³ 250 500 800 1000 1,600 Scale In Feet Scale In Feet Y:\Santa_Susana\EP9038\Soil_Sampling\Report\ Fig2-4_DrainagePathways.mxd Project: EP9038 Source: Boeing 2009, CIRGIS 2007, HGL 2010 11/1/2012 pbillock HGL—Radiological Characterization of Soils in Area IV and NBZ, SSFL—Ventura County, California Figure 2.5 Geologic Map Santa Susana Field Laboratory Northern Buffer Zone U.S. EPA Region 9 Legend AREA IV AREA II Administrative Boundaries at the Santa Susana Field Laboratory AREA I Santa Susana Field Laboratory Property Boundary AREA III Geologic Formation Southern Buffer Zone ³ 0 500 1000 Scale In Feet 2000 Qof Old alluvial-fan deposits, Undivided (late to middle Pleistocene) Tm Modelo Formation Undivided (late Miocene) Tcb Calabasas Formation, Undivided (early late Miocene and late middle Miocene) Tsi Simi Conglomerate, Undivided (Paleocene) Tlv Las Virgenes Formation (Paleocene) Tss Santa Susana Formation (early Eocene to late Paleocene) Kc Chatsworth Formation (late Cretaceous) G o Anticline Strike and Dip of Bedding Fault (approximate location) Y:\Santa_Susana\EP9038\Soil_Sampling\Report\ Fig2-5_GeologicMap.mxd 11/1/2012 pbillock Source: Preliminary Geologic Map of the Los Angeles 30´ x 60´ Quadrangle, Southern California; Yerkes and Campbell; 2005 Coordinate System: NAD83 CA State Plane V Northern Buffer Zone East Sodium Reactor Experiment (SRE) Complex St. 3r d Radioactive Materials Handling Facility (RMHF) Complex Subarea 3 Subarea 7 Southern California Edison Substation Outfall #3 See Inset Shield Test Irradiation Reactor SRE Dam SNAP Experimental Reactor Facility Former Building 4010 4723 4724 4163 Northern Buffer Zone West F St. 4143 4003 4693 4133 4825 4654 Subarea 8 North ES t. 4014 Subarea 6 4040 4665 4664 4056 Landfill 4035 4021 4075 4614 4621 Old Conservation Yard 4103 4022 4083 4663 4093 4046 4064 4073 New Conservation Yard Drainage 4641 Building 4009 Leachfield 4036 4625 S t. Sodium Graphite Reactor/ Organic Moderated Reactor Building 4009 h 10t 4028 4037 4027 4024 G S t. 11th St. Engineering Test Building Former Building 4003 4010 4025 4023 12 th 17th St. Former Sodium Disposal Facility S t. 17th St. 4013 4042 4019 4006 4356 Empire State Atomic Development Associates (ESADA) Fuel Element Storage Facility 4005 4362 4026 4059 4826 Subarea 5A 4816 4039 t 17 h St . 4057 Building 4029 4626 4038 L85 Nuclear Experimentation Reactor - Building 4093 t 20 h St 4062 . t 18 h St . Kinetics Experiment Water Boiler - Former Building 4073 4066 4065 Former Building 4023 4011 F St. Former Building 4005 4609 4486 4885 24th St. 4463 4462 Heavy Metal Likely Remediation Zone 4483 4485 4482 4487 4100 4484 4461 4383 Subarea 5B G St. s F ir e Liquid and Gas Radioactive Storage Tanks Subarea 7 Northern Panhandle 17th Street Drainage 4009 Arnes Inset SRE Pond Building 4006 Rd. 4374 4055 4373 H St SRE Dam Former Building 4356 4015 4848 22nd St. 4020 Building 4011 Building 4019 4723 J St. Subarea 5C 4425 4874 4814 4314 4318 4875 24th St. 4353 4363 I St. Fast Critical Experiment Building 4100 Hazardous Waste Management Facility Building 4133 4163 4143 Subarea 5D North 4373 Leach Field Plutonium Development Facility Building 4055 Subarea 8 South Radioactive Materials Handling Facility Complex 4693 Sodium Reactor Experiment Complex RMHF Leachfield Outfall #3 Hot Lab - Former Building 4020 4825 Site 4614 RMHF Holdup Pond/Catchment Basin 4664 4621 Subarea 5D South 4083 4663 HGL—Radiological Characterization of Soils in Area IV and NBZ, Santa Susana Field Laboratory—Ventura County, California 3 times to less than 4 times FAL (0.579 to 0.771 pCi/g) Greater than 4 times FAL Figure 4.1 Cesium-137 Round 1 and 2 Surface Soil and Sediment Results Santa Susana Field Laboratory Area IV and NBZ Radiological Study Roads (Below 0.193 pCi/g) (0.386 to 0.578 pCi/g) (0.772 to 196 pCi/g) Approximate Drainage Pathways Chemical (as of 5/2012) 20-foot elevation contours Structures Existing Removed t. 11th St. Legend 2 times to less than 3 times FAL St. GS 4027 4025 Likely Remediation Zones 4064 10th 4037 4010 (0.193 to 0.385 pCi/g) 4046 Kinetics Experiment Water Boiler Former Building 4073 4036 4625 4024 FAL to less than 2 times FAL 4035 4641 Shield Test Irradiation Reactor Below FAL L85 Nuclear Experimentation Reactor Building 4093 4103 4021 4075 Subareas 4014 4665 4022 Cesium-137 (FAL = 0.193) t. ES Interim Storage Facility Building 4654 Former Buildings 4375 and 4875 Former Buildings 4173/4865 Engineering Test Building Former Building 4003 4003 Former Building 4353 Pond Dredge Area Hot Oil Sodium Cleaning Facility 4724 Building 4015 Notes: FAL - Field action level KEWB - Kinetics Experiment Water Boiler NBZ - Northern Buffer Zone SNAP - Systems Nuclear Auxiliary Power RMHF - Radioactive Materials Handling Facility pCi/g - picocuries per gram 0 250 ³ 500 Feet U.S. EPA Region 9 1000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\FAL_Plates\ Fig4-1_Cs-137_Surface.mxd 12/19/2012 pbillock Boeing 2011, HGL 2012 Northern Buffer Zone East ! ! ! ! Sodium Reactor Experiment (SRE) Complex ! ! ! ! St. 3r d Radioactive Materials Handling Facility (RMHF) Complex ! ! ! ! ! ! ! ! ! ! ! ! ! Subarea 3 ! ! Subarea 7 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Outfall #3 ! See Inset ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Northern Buffer Zone West ! ! ! ! ! ! ! ! ! ! ! ! ! Subarea 8 North ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 4654 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! 4614 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 4028 ! 4625 ! 4036 ! ! ! ! ! ! ! ! ! ! ! ! ! 4019 ! 4059 ! ! 4356 ! ! ! 4038 ! 4826 ! ! ! ! ! ! ! ! ! 4609 ! ! ! ! ! ! ! ! ! ! ! ! ! ! t 18 h St . ! ! ! ! ! ! ! ! ! ! ! ! s F ir e ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 4020 ! ! ! ! ! ! !! ! ! ! ! ! 4425 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 17th Street Drainage Building 4006 ! 4363 ! ! ! ! ! ! ! ! ! I St. ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! Subarea 8 South ! ! ! ! ! ! Hazardous Waste Management Facility Building 4133 ! ! ! ! ! ! ! ! ! Radioactive Materials Handling Facility Complex Former Building 4353 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Site 4614 RMHF Holdup Pond/Catchment Basin ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 4621 ! ! ! 4021 4075 ! ! ! 4663 ! ! ! ! ! ! ! ! ! 4625 ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! 4024 FAL to less than 2 times FAL (0.193 to 0.385 pCi/g) 2 times to less than 3 times FAL (0.386 to 0.578 pCi/g) 3 times to less than 4 times FAL (0.579 to 0.771 pCi/g) Greater than 4 times FAL (0.772 to 74.9 pCi/g) Likely Remediation Zones Chemical (as of 5/2012) Structures Existing Removed There were no samples which corresponded to the boxed symbol. 4046 ! ! ! ! ! ! ! ! ! ! ! ! ! 4064 ! ! 4641 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! GS t. 11th St. ! ! ! HGL—Radiological Characterization of Soils in Area IV and NBZ, Santa Susana Field Laboratory—Ventura County, California 4025 (Below 0.193 pCi/g) ! ! ! 4027 ! ! 4010 ! ! ! 4037 ! ! ! ! ! 4036 ! ! Kinetics Experiment Water Boiler Former Building 4073 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! St. ! ! ! ! ! ! ! ! ! ! 4014 4035 ! 10th Shield Test Irradiation Reactor ! ! ! ! ! ! ! ! ! ! ! ! ! ! t. ES ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! 4083 ! ! ! ! ! ! L85 Nuclear Experimentation Reactor Building 4093 ! ! ! ! ! ! ! ! 4103 4022 ! ! ! ! ! 4825 ! ! ! ! ! 4664 ! ! ! ! ! ! ! ! ! ! 4665 ! ! ! ! ! ! Subarea 5D South ! ! ! ! ! ! Interim Storage Facility Building 4654 ! ! ! ! 4693 ! ! ! ! ! ! ! ! ! ! ! Sodium Reactor Experiment Complex ! ! ! ! ! ! ! ! Hot Lab - Former Building 4020 ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! RMHF Leachfield 4003 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Below FAL ! ! ! ! ! Outfall #3 ! Subareas ! 4143 ! ! ! Cesium-137 (FAL = 0.193) !! ! ! Engineering Test Building Former Building 4003 ! ! ! ! ! ! ! ! ! ! ! ! ! 4163 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Plutonium Development Facility Building 4055 Legend ! 4724 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Hot Oil Sodium Cleaning Facility ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 4723 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Former Buildings 4173/4865 ! ! SRE Dam ! ! ! ! ! ! ! ! ! ! ! ! ! ! Pond Dredge Area ! ! ! Fast Critical Experiment Building 4100 Former Buildings 4375 and 4875 ! ! ! ! ! ! 4373 Leach Field ! ! ! ! ! ! ! ! ! ! ! ! ! ! Subarea 5D North ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Building 4011 ! SRE Pond ! Former Building 4356 ! Liquid and Gas Radioactive Storage Tanks ! Building 4015 4353 ! ! ! ! ! ! Subarea 7 Northern Panhandle Subarea 5C ! ! ! ! ! ! ! ! Subarea 5B ! ! ! ! ! ! ! Building 4019 ! ! ! ! ! ! ! ! Inset ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! J St. ! !! ! ! ! ! 4874 ! ! ! ! ! ! ! ! ! ! ! ! ! 4875 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 4318 4314 4814 ! ! ! ! 4373 ! ! ! ! ! ! !! ! ! ! 4015 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 4848 ! !! ! ! 4374 4055 ! ! ! ! ! ! ! ! ! ! ! ! ! ! H St ! ! ! ! Heavy Metal Likely Remediation Zone ! ! ! Former Building 4005 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Former Building 4023 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! G St. ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Rd. ! ! ! ! ! ! ! ! ! ! ! ! 4009 ! ! ! ! ! ! ! Arnes ! ! ! ! ! ! ! 4383 ! ! ! ! ! ! ! ! ! ! ! ! ! 4482 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 4484 4485 4487 22nd St. ! ! ! ! ! 24th St. ! ! ! ! ! ! ! ! ! 4483 Kinetics Experiment Water Boiler - Former Building 4073 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! L85 Nuclear Experimentation Reactor - Building 4093 ! ! ! 4461 Building 4029 ! ! ! ! ! ! ! ! ! ! ! ! ! 4486 ! Subarea 5A ! ! ! ! ! 4462 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 4100 ! ! ! ! ! 4463 ! ! ! ! ! ! ! ! ! !! ! ! ! ! 24th St. 4885 ! ! ! ! ! Fuel Element Storage Facility ! ! ! ! ! ! ! ! ! ! ! ! 4011 ! ! ! ! ! 4066 ! ! ! ! ! . ! ! ! ! ! ! ! ! ! ! ! ! F St. ! ! ! ! ! ! St ! ! ! ! ! ! ! !! ! ! Engineering Test Building Former Building 4003 ! ! ! ! ! ! ! ! ! ! ! 4065 ! ! S t. S t. ! ! ! ! ! ! ! ! ! h 4062 ! ! New Conservation Yard Drainage ! ! ! ! ! ! ! t 20 ! ! ! ! ! ! ! ! ! ! ! Old Conservation Yard ! ! ! ! ! ! ! ! ! ! ! G ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! . ! ! ! ! 4064 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! St ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 12 th ! h ! ! ! ! ! ! ! ! ! Subarea 6 ! ! ! 11th St. ! 4042 ! ! ! ! ! ! ! !! ! ! 4816 ! ! ! 4626 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! t 17 ! ! 4023 ! ! ! ! ! ! ! ! ! ! ! 4040 ! ! ! ! ! ! ! ! ! ! ! ! 4026 ! ! 4057 ! ! ! ! ! ! ! ! ! ! ! 4006 ! ! ! 4641 ! ! ! ! ! 4005 ! 4014 ! ! ! ! ! ! S t. ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 4039 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 4025 ! ! ! !! ! ! ! ! ! ! ! ! 17th St. ! ! ! ! 4362 ! ! ! ! ! ! ! 4024 ! ! ! ! ! 4035 4046 4093 ! ! ! ! ! ! ! ! ! ! ! 4013 ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! E ! 4027 17th St. ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 4037 ! ! ! ! ! ! ! ! ! 4010 ! ! ! ! !! ! ! ! ! ! !! ! ! !! ! ! ! ! ! ! ! ! ! !! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! !! ! ! 4693 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 4083 ! ! ! ! ! !! !! ! !!!! ! ! !! ! ! S t. ! ! ! ! ! ! ! ! ! ! 4003 ! 4073 F St. ! ! ! ! ! ! ! ! ! 4663 ! ! ! ! ! 4825 4103 ! ! ! ! ! ! ! ! ! ! 4021 4621 ! ! ! ! h 10t ! 4724 ! ! ! ! ! ! ! !! !! ! !! ! ! ! ! ! ! ! ! 4664 4075 ! ! ! ! ! ! ! ! ! ! ! ! ! ! 4022 ! ! ! ! ! ! ! ! 4665 ! ! ! ! ! ! ! ! ! ! ! ! ! 4723 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! 4163 ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 4133 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! SRE Dam ! ! ! ! ! ! 4143 ! ! ! ! !! ! !! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! !! !! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Empire State Atomic Development Associates (ESADA) ! ! SNAP Experimental Reactor Facility Former Building 4010 Former Sodium Disposal Facility ! ! ! ! Sodium Graphite Reactor/ Organic Moderated Reactor Building 4009 ! ! ! ! Building 4009 Leachfield ! ! Shield Test Irradiation Reactor 4056 Landfill Southern California Edison Substation ! ! ! ! ! ! ! Figure 4.2 Cesium-137 Round 1 and 2 Subsurface Soil and Sediment Results Santa Susana Field Laboratory Area IV and NBZ Radiological Study Roads Approximate Drainage Pathways 20-foot elevation contours Notes: FAL - Field action level KEWB - Kinetics Experiment Water Boiler NBZ - Northern Buffer Zone SNAP - Systems Nuclear Auxiliary Power RMHF - Radioactive Materials Handling Facility pCi/g - picocuries per gram 0 250 ³ 500 Feet U.S. EPA Region 9 1000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\FAL_Plates\ Fig4-2_Cs-137_Subsurface.mxd 12/19/2012 pbillock Boeing 2011, HGL 2012 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # Northern Buffer Zone East * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # Sodium Reactor Experiment (SRE) Complex * # * # * # St. 3r d * # Radioactive Materials Handling Facility (RMHF) Complex * # * # * # * # * # * # # * * # * # * # Subarea 7 * # * # * # * # * # * # # * # * # # * * * # * # # * * * # # * # * ## * * *# # *# ## * * * # * # * # * # * # * # Subarea 8 North * # # * * # * #*# * * # # # * * * # # * *# ## * * # * # * # * # * # 4056 Landfill Building 4009 Leachfield # * # * * # * # * # # * * # * * # * ## # * * # * # # * # * * *# # *# * # * # # * # *# * Former Sodium Disposal Facility * # * # 4005 4356 4059 * 4023 # * # 12 th * # S t. * # * # * ## * S t. Engineering Test Building Former Building 4003 * # * # * # * # * # * # * # * # * # * # Subarea 5A Building 4029 * # * # * # L85 Nuclear Experimentation Reactor - Building 4093 * # . t 18 h St . Kinetics Experiment Water Boiler - Former Building 4073 * # * # * * # # * * # # # # * * * # * # * # * # * # * # * # * # * # * # * # * # Rd. * # * # # *#* * # * # * # * # * # * # * # * # * # * # # * * # # * * # * # * # * # * # * # * # 4314 * # * # * # * # # * * # * # * ## * * *# # * * # # # * * # * # # * * # * # * * # # # * *# # *# * * # * # * * # # 4318 * # * # * # # ** # # * * * # * # # * # 4425 # * * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # * # ## * *# * * # * # * # * # * * # # * # # * * # # * * # * # * # * # * # * # 4353 # * * # # * * * # # * # * # # * * # * # * # * *# # # *#*#* * # # * * # # * * # # * * # * # * # * # * ## * * # # # * * * # # * * # * # * # Subarea 8 South * # * # * # Radioactive Materials Handling Facility Complex Former Buildings 4375 and 4875 * # Pond Dredge Area Former Buildings 4173/4865 * # # * * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # Interim Storage Facility Building 4654 * # # * * # * # * # * # * # * # * # 4665 * # # * # * * # * # * # # * * # 4621 * # * # * # * # * *# # * # * # * # # * Strontium-90 GEL (FAL = 0.387) Below FAL * # TAL (FAL = 0.0750) (Below 0.387 pCi/g) (Below 0.0750 pCi/g) FAL to less than 2 times FAL # * (0.387 to 0.773 pCi/g) (0.0750 to 0.149 pCi/g) 2 times to less than 3 times FAL # * (0.774 to 1.15 pCi/g) (0.149 to 0.224 pCi/g) 3 times to less than 4 times FAL # * (1.16 to 1.54 pCi/g) (0.225 to 0.299 pCi/g) Greater than 4 times FAL # * (1.55 to 21.3 pCi/g) (0.300 to 0.563 pCi/g) Subareas Likely Remediation Zones Chemical (as of 5/2012) Structures Existing Removed There were no samples which corresponded to the boxed symbol. 4825 4036 4625 * # * # # * * # * # * # t. ES L85 Nuclear Experimentation Reactor Building 4093 * # * # 4014 4035 * # * # * # 4046 4037 * # * # * # 4064 * # * # Kinetics Experiment #* * # Water Boiler * # Former Building 4073 * # * # * # * # * # * # * * # # GS 4027 t. 11th St. 4010 * # * # HGL—Radiological Characterization of Soils in Area IV and NBZ, Santa Susana Field Laboratory—Ventura County, California Figure 4.3 Strontium-90 Round 1 and 2 Surface Soil and Sediment Results Santa Susana Field Laboratory Area IV and NBZ Radiological Study Roads Approximate Drainage Pathways 20-foot elevation contours * * # # * # 4641 4025 Legend * # * # * # * # 4024 * # * # # * * # 4083 * # * # # * * # * # 4103 * # Shield Test Irradiation * # Reactor * # * # * # * * # # * # * # * # * # * # * # 4021 4663 * # # * * # * # * # * # 4664 4075 * # * # * # * # St. # * * # # *#* * # * # * # * # * # * *# # * # * ## * * # Sodium Reactor Experiment Complex * # * # * # 10th * # * # * # * # * # # * * # * # # * * # 4693 * # * # # * * * # # * # * # * ## * * # * # * # * # * # 4022 * # * # * # * # * # # * * # * # * # * # # * # * * # # * * # * # * # * # * # Subarea 5D South *#* # * # * # *# * # *# *# # * # * * # * # * # * # Engineering Test Building * # Former Building 4003 4003 * # * # * # # * * # * # * # 4143 * # * # # * *# # * * # * # # * * # * # * # * # # * * # * # * # * # # *#*#*#* * # # * * # * # 4163 # * * * # # * # * # # * * # * # * # Site 4614 RMHF Holdup Pond/Catchment * # Basin * # * # * # * # 4724 * # * # * # * # * # RMHF Leachfield * # * # # * * # * # * # * # * # * # Hot Oil Sodium Cleaning Facility * # # * * # ** # # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # 4723 * # * # Outfall #3 Hot Lab - Former Building 4020 * # # * * # * # * # * # * # * # * # SRE Dam * # * # * # * # Former Building 4353 * # * # * # Plutonium Development Facility Building 4055 * # * # # * Hazardous Waste Management Facility Building 4133 * # 4373 Leach Field * # * # * # * # * # * # * # Subarea 5D North * # # * * # # * * # * # * # * # * # * # * # * # # * # * * # *#* # * # * # * # * # * # * # * # * # # * * # * # # * * # * * # # * # * # # * * # * # * *# # * # # * #* * # Fast Critical Experiment Building 4100 * # * # * # * # * # * # Building 4015 * # * # Subarea 5C * # * # # * * # * # * # * # * # * # * # *# # *# * * # * # * # * # * # # * #* * # * # * # * # * # # * #* * # * # * # * # * # * # # * # * * # # * * # * # # * * # * # * # Building 4019 * # I St. * # * # Building 4011 * # # * * # * # * # * # 4874 # # * * # * # # * # ** * * # # *# 4875 * # # * * # * # # * * # * # * # * # # * * # * * # # * * # * # # * # * # * # # * * # * # * 4363 # * # * # SRE Pond * # * # * # * # * # Former Building 4356 4015 # * * # * # * # # * * # * # * # 4374 * # 4848 * * # * # # * # * 4373 # * * # # * # * # *# # * # * # * * # * # J St. 4055 Liquid and Gas Radioactive Storage Tanks Subarea 7 Northern Panhandle Building 4006 * # * # * # * # * # * # # * # * * # * # * # * # # * 17th Street Drainage * # * # # **#*#*#*#* * # # * # # * * # # * * # * # # * # * # * * # * # * # * # * # # * Inset Subarea 5B G St. # # * * * # * # * # * # * * *# # *# # *# * # * # 4020 # # * *# *# # * * * # * # *# * * # *# # * * # * # # * # * # * # * # * # * # * # # # * * * # # *# * *# # *# # * * # *#*#* #* #*#*#* * # * # * # * # * # * # 4814 * # H St * # * # * ## * * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # # * * # * # * # * # * # # * * # * # * # * # * # * # * # 4009 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # 4383 * # * # s F ir e 4482 * # 4461 * # * * # # * # Heavy Metal Likely Remediation Zone 4483 4484 4485 22nd St. * # * # Arnes 4462 * # * # * # * # 4463 4100 * # * # * # Former Building 4005 * # 4011 4487 * # * # Former Building 4023 * # 4486 # * 4885 * # * # # * 4609 24th St. * # * * # # F St. 24th St. * *# # # * * # * # * # * # * # 4066 4065 * # * # * # * # # * Fuel Element Storage Facility * # . 4062 St * # * # * # * # * # * # New Conservation Yard Drainage * # * # * # * # Old Conservation Yard * # # * * * # # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # * # 4626 * # * # * * # # * # * # * # * # * # * # * # # * # * * # * * # # * # * # # * # * 4064 * # # * * # * # * * # *# # *# # * ## * * # * # * * # * # 4038 * # * # 4641 * # * # 4035 * # Subarea 6 * # * # # * * # * # * # * # * # * # St 4057 * # * # * # * # 4046 4093 * # ## * * * # h # * * # 4040 * # t 20 # * * # * # # * 4816 4039 * # * # # * * # * # * # * # * # * # * # * 4014 # h * # * # * # t. * # * # * # 4826 * # * # * # ES * # * # # * * # * # 4026 * # * # * # t 17 * # * # ## * * * # 4006 * # * # * # # * * # * # * # 4042 * # 4362 * # * # # * * ## * * # # * # * * # * # * * # # # * *# *# # *# * 4825 * # * ## * * *# # * # 4013 * # * # * # * # * # * # 4019 * # 4724 # * *# # * * # G 4025 * # * # * # * # # * 4027 17th St. * # * # # * *# # * * # 17th St. * # * # * # 4723 * # ## * * 4010 * ## * * # * # * # Empire State Atomic Development Associates (ESADA) * # 4037 * # # * * # # * 4036 * # * # * # * # S t. * # * # * # * # * # 4083 4625 * # * # * # F St. * # 4073 ## * * * # * # SRE Dam * # * # * # * # * # * * # # 11th St. * *# # * # * # * # 4654 # * * # * # * # # * 4693 * # * # * # 4663 * # * # 4024 * # # * 4133 4103 * # * # * # * # 4021 * # # * * # * # * # h 10t * # * # * # # * * # * # * # * # # * * # * # * # * 4003 # 4022 # * * # Sodium Graphite Reactor/ Organic Moderated Reactor Building 4009 * # * # # * * # # # *# # *# * # *# # *#* #*# * ** * * *# *# # * # *# * *# # * # * # 4665 * # * # *# # * 4664 # # * * * * # *# # *# # * # *# * # *# * # * # * * # * # 4075 * # *# # * # * # *# # * * * # # *# # * * # * 4614 4621 * * # # # * * # * # * # * # # * * # # * * # * # * # * # 4028 * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # * # * # * *# # * # # * #* # *#*#*#* #*#* *#* #* * # # * # 4143 * # ## * * * # * # * # * * # * # # * # * # * # * # * # 4163 * # * # * # * # * # * # # * # * * # * # * * # # * # * # * # * # * # * # * # * # * * # # # * * # * # * # * * # # # # * **# * *# # * # * * # # # # * # * *# * *# # * * # * # * * # # * # * # * *# # # * * #* * # # *# # * * # * # * # * # * *# # * # * # * # * # # * * # * # Southern California Edison Substation * # * # * ## * * # * # * # * # * # * # See Inset Northern Buffer Zone West * # * # * # # * * # * # * # # * SNAP Experimental Reactor Facility Former Building 4010 * # * # * # * * # # Shield Test Irradiation Reactor * # Subarea 3 * # * # * # * # * # * # Outfall #3 # * * # Notes: CL - Critical level FAL - Field action level GEL - GEL Laboratories, Inc KEWB - Kinetics Experiment Water Boiler NBZ - Northern Buffer Zone SNAP - Systems Nuclear Auxiliary Power TAL - Test America Laboratories RMHF - Radioactive Materials Handling Facility pCi/g - picocuries per gram 0 250 ³ 500 Feet U.S. EPA Region 9 1000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\FAL_Plates\ Fig4-3_Sr-90_Surface.mxd 12/19/2012 pbillock Boeing 2011, HGL 2012 Northern Buffer Zone East * # * # * # * # Sodium Reactor Experiment (SRE) Complex * # * # * # * # St. 3r d Radioactive Materials Handling Facility (RMHF) Complex * # * # * # * # # * * # * # * # * # Subarea 7 * # # * * # Outfall #3 * # # * * # * # * # * # Subarea 8 North * # * *# ## * * # * # * # * # 4056 Landfill ##* #* ** # # *#*#* * * # # * # *# # *# * # *# * * * # # * # * # * # * # 4614 * * # # * # * # * # * # Building 4009 Leachfield * # * # # * # * * # * # * # * # * # * # 4103 * # # * * # * # * # * # * # * # * # 4037 4024 * # * # * # 4040 * # * # # * * * * # # # * # * # # * # * 4064 * # # * * *# # * # * * # # * # * # Old Conservation Yard # * * # * # * # * # * # S t. * # * # # * * # *# # * * 4023 # # * * # Engineering Test Building Former Building 4003 12 th S t. * # * # Fuel Element Storage Facility * # 4005 4006 4356 4026 4059 * # * # * # * # 4826 * # * # 4816 4039 Subarea 5A * # # * t 17 * # * # h * # St . 4057 * # * # 4626 * # Building 4029 * # * # * # 4038 L85 Nuclear Experimentation Reactor - Building 4093 * # * # * # 4062 St t 18 . # * h * # * # t 20 * # * # h St . * # Kinetics Experiment Water Boiler - Former Building 4073 * # * # 4066 4065 * # * # * # Former Building 4023 * # * # * # * # * # 4609 4486 * # * # * # * # * # *# # * # ** # # * *# # * # * * # s F ir e Rd. * # * # * # * # * # * # * # * # * # # * * # * # 4814 * # * # * # * # * # * # * # * # * # * # * # # * * # 4314 # # * * * # *# # *# * * # 4318 * # # * * * # # # * # * * # * 4425 # # * * # * # * * # # * # * # * # * # * # * # * # * # # * # # * * * # * # * # * # * # * # # # * * * # * # * # * # * # # * * # # * * # * # * # * # * # * # * # * # # * * # *# * *# # * # * # # * *# *# # * * # * # * # * # * # * # * # * # * # * # * # ## * * *# * # * # * # Former Buildings 4375 and 4875 * # Pond Dredge Area # * Former Buildings 4173/4865 * # Radioactive Materials Handling Facility Complex * # * # * # * # # * # * * # * # * # # * 4621 * # # * * # Strontium-90 GEL (FAL = 0.387) Below FAL * # TAL (FAL = 0.0750) (Below 0.387 pCi/g) (Below 0.0750 pCi/g) FAL to less than 2 times FAL # * (0.387 to 0.773 pCi/g) (0.0750 to 0.149 pCi/g) 2 times to less than 3 times FAL # * (0.774 to 1.15 pCi/g) (0.149 to 0.224 pCi/g) 3 times to less than 4 times FAL # * (1.16 to 1.54 pCi/g) (0.225 to 0.299 pCi/g) Greater than 4 times FAL # * (1.55 to 21.3 pCi/g) (0.300 to 0.563 pCi/g) Subareas Likely Remediation Zones Chemical (as of 5/2012) 4664 Structures Existing Removed There were no samples which corresponded to the boxed symbol. * # * # * # * # * # * # * # * * # # 4825 * # # * * # * # * # t. ES * # 4014 4103 4021 * # # * * # # * * # 4083 4663 * # * # # *#* * *# # * # 4035 L85 Nuclear Experimentation Reactor Building 4093 * # * # * # * # * # 4046 * # * # * # 4064 * # * # * # 4641 * # * # * # * # * # * # * # 4036 4625 * # 4037 * # * # Kinetics Experiment Water Boiler Former Building 4073 * # * # * # GS 4027 4024 * # 4010 * # * # * # * # HGL—Radiological Characterization of Soils in Area IV and NBZ, Santa Susana Field Laboratory—Ventura County, California Figure 4.4 Strontium-90 Round 1 and 2 Subsurface Soil and Sediment Results Santa Susana Field Laboratory Area IV and NBZ Radiological Study Approximate Drainage Pathways Notes: FAL - Field action level GEL - GEL Laboratories, Inc KEWB - Kinetics Experiment Water Boiler NBZ - Northern Buffer Zone SNAP - Systems Nuclear Auxiliary Power TAL - Test America Laboratories RMHF - Radioactive Materials Handling Facility pCi/g - picocuries per gram 0 250 ³ 500 Feet t. 11th St. * # Roads 20-foot elevation contours # * * # * # * # 4025 Legend * # 4693 * # * # * # # * * # # * # # * # * * 4665 * # * # * # # * * # * # * * # # # * * * # # * * # *# # *# # * * # * # # * * # * # * # Interim Storage Facility Building 4654 * # * # * # * # * # Sodium Reactor Experiment Complex * # * * # # 4003 * # * # Engineering Test Building * # Former Building 4003 * # * # * # * # # *#* * # * # * # * # * # St. Shield Test Irradiation * # Reactor * # * # * # * # # * * # *# # * * # * # * # * # Hot Oil Sodium Cleaning Facility * # * # * # * # * # * # 4163 * # 4143 * # * # * # * ## * * * # # *# * # # * * * # * # # *# # * * # * # * # * # 4075 * # * # * # ## * * * * # * ## * # * # ** # *# # * # * # * # * # * # * # 4022 * # * # * # # * #* * # * # # * * # # * # * * * # # * # * # # * * # * # 4724 * # 10th * # # * * # * # * # * # * # # * * # * # * # # * #* * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # # * * # * # # * # * * # # * * # * # * # # * * # * # * # * # * # # * * * # # * # * # *# # *# # *#* #* *# * * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # Subarea 5D South * # * # * # * # * # * # * # * # RMHF Leachfield * # Site 4614 RMHF Holdup Pond/Catchment * # Basin * # * # * *# # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # Outfall #3 * # * # # * * # * # * # 4723 * # * # * # Hot Lab - Former Building 4020 * # * # * # * # * # * # * # * # * # * # * # SRE Dam * # # * * # * # * # * # * # * # * # # * Hazardous Waste Management Facility Building 4133 * # * # # * Former Building 4353 * # * # * # * # # * #* * # * # # * * # * # # * * # Plutonium Development Facility Building 4055 * # * # * # Subarea 8 South * # * # 4373 Leach Field * # * # * # * # Subarea 5D North * # * # * # * # * # * # Fast Critical Experiment Building 4100 * # * # * # * # * # * # * # # * * # # * * # Building 4015 4353 * # * # * # Subarea 5C * # * # * # * # * # * # * # * # I St. * # * # Building 4019 * # SRE Pond * # Building 4011 * # 4874 * # * # * # * # # * * # * # Liquid and Gas Radioactive Storage Tanks * # Former Building 4356 4015 * # * # # * * # * * # # * # * # * # # * # * * # * # * # * # * # * # # * * * # # * * # # * * # * # # * # * # * # # * * # * # # * * # * 4363 # * # # * * # # * 4374 * # * # 4848 * * # * # # * # * 4373 # * * * # # * # # * # * # * # * # *# *# # * * # * # J St. 4055 Subarea 7 Northern Panhandle Building 4006 * # # *# * * # * # * # * # * # # *#* 17th Street Drainage * # * # * # # * * # * # # ** # * * # # *# 4875 * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * * # #* * ## # * * *# # # * # * * # # * * # * # * # * # * # Inset Subarea 5B G St. * # * # * # * # # * # *# * * # * # * # * # * # * # * # * # * * # * # *# # *# * *# * # * # # * # * # *# # ** # * *# # * # * * # # * * # * # *# # * # * # * # * # * * # # * # * # * *# *# * # * # # * # * * # *# # *# # *# * * # * # 4020 * # * * # # * * # # * # * * # * # # * * # * # # * # * # * # * # * # # * * # * # * # # * * # * # H St # * # * * # * # * # * # # * * * # ## * # * *# # * * # * # * # *# # * # * * # # * * # * # * # # * * # * # * # 4482 * # 4461 * # * # * # # * * # # * * # * # *# # * * # * # # * * *# # * # * # Heavy Metal Likely Remediation Zone 4483 4484 4485 4100 4009 * # 4462 4383 * # * # # * * # * # # * * # * # # * * # * * # # * # Arnes 4463 4487 * # * # # * * # * # * * # # * # * # * # * # * # * # 22nd St. 4885 * # Former Building 4005 * # * # * # 24th St. * # * # * # 4011 F St. 24th St. * # New Conservation Yard Drainage * # 4042 * # * ## * * # # * * # 11th St. * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # G # * * # 4013 4362 * # Subarea 6 * # * # # * * # * 4014 # S t. * # * # * # * # 4641 * # * # * # # * * # * # # * * # * # ## ** # *# * * # # * * # * # Empire State Atomic Development Associates (ESADA) * # * # * # * # 4027 4019 * # * # * # * # * # 4036 17th St. * # * # * # * # * # 4625 * # * # * # # * 4046 # *#* #* 17th St. * # 4693 E 4093 * # * # * # * # # * * # # * * # 4025 * # * # * # F St. 4003 # * * # * # # * * # * # *# # *# * * # * # * # * # # * * # * ## * * # * # * # * # # * * # 4083 * # * # * # * # * # *#* ##*# * * # * # 4010 * ## * * # * # 4035 4073 * # * # * # * # * # * # * # * # * # * # * # *# # * * # * # * # 4724 * # * # * # 4163 * # * # * # 4663 * # 4621 * # # * SRE Dam # * *# # * * # 4825 4022 * # * # * *# # # * * *# * *# *# *# # * # *# * # *# # * 4143 * # * # # * # * # * # * * # * # # * # * # * # # * * # * # * # 4021 4075 * # * # 4654 # *# * *# * *# # * # * # # * # *#*#* #* * # * # * # * # # * * # * # * # * # * # 4723 * # * # * # * # * # * # # * * * # # * # * # * # * # * # # * * # # * 4665 4664 * # * # * # * # # * * # * # * # Southern California Edison Substation * # * # * # * # * # S t. ##*#* # * #*#** * # * # * * # # * # * # * # * # * # h 10t * # * # * # * # ## * * # * * # # * # * * # * # # * # * * # *# # *# * *# # *# ** # * # * * # *# # *# * # 4028 * # * # # * * # * # * # * # * # * # * # # * * # * # *# # * *# *# # * # ** * # # * *# # *# # *# # *# * * * # * # * # # * * *# # * # # * * *# # * # * # * # * # * # # 4133 ** # # * * # * # * # * # # * * # * # # * # ** # * # * # * # # * * # * # * # # * * # * # * # * # * # * # Former Sodium Disposal Facility * # * # * # # * * # # # * ** # * # * # # * * # * # * # * # * # * # # * #* #* #* *# # * *# ** *# # *# # * * # # # **# # * # * * # * * # # * * # * # # Northern Buffer Zone West Sodium Graphite Reactor/ Organic Moderated Reactor Building 4009 * # * # * # * # Subarea 3 * # * # # * * # * # * # * # * # SNAP Experimental Reactor Facility Former Building 4010 * # # * # * * * # # * # * # * ## * * # * # * # # * # # * * * # # # * * * # # * * # *# * # * # * # * # * # # * * # * # * # * # * # # * See Inset Shield Test Irradiation Reactor * # * # * # # * * ## * * # * # * * # # * # * # * # * # # * * # * # U.S. EPA Region 9 1000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\FAL_Plates\ Fig4-4_Sr-90_Subsurface.mxd 12/19/2012 pbillock Boeing 2011, HGL 2012 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # Northern Buffer Zone East * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # Sodium Reactor Experiment (SRE) Complex * # * # * # St. 3r d * # Radioactive Materials Handling Facility (RMHF) Complex * # * # * # * # * # * # # * * # * # * # Subarea 7 * # * # * # * # * # * # * # # * * * # # ## * * * * # ## * * # * # * # # * * # * # * # * # * # * # 4056 Landfill * # * # # * * # Building 4009 Leachfield * # * # * # * # * # * # * # 4621 * # * # * # * # # * * * # # 4005 4026 * # 12 th * # * ## * S t. Engineering Test Building Former Building 4003 S t. * # * # * # * # * # * # * # * # * # * # * # * # * # Subarea 5A . * # # * * * # # * # h St 4062 . t 18 * # * # * # # * * # Building 4029 * # * # * # L85 Nuclear Experimentation Reactor - Building 4093 * # t 20 * # h St . Kinetics Experiment Water Boiler - Former Building 4073 * # * # * # # * * # * # * # * # 4885 * # * # * # * # * # * # * # * # * # Rd. * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # 4314 * # * # * # * # * # 4814 * # * # * # * # * # H St * # * # * # * # # * * # * # * # * # * # # # * * * # * # *# # *# * * # * # 4318 # * * # # * * * # * # # * # 4425 * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # * * # # * # * # * # # * * # # * * # * # * # * # * # * # * # * # 4353 * # * * # # * # * # * # * # * # # * * # # * * * # # * # * # # * * # * # * # * # * # * # * # * # * # * # * # * # Radioactive Materials Handling Facility Complex * # * # Outfall #3 Former Building 4353 * # Pond Dredge Area Former Buildings 4173/4865 * # Site 4614 RMHF Holdup Pond/Catchment * # Basin * # * *# # * # * # * # Subarea 5D South * # * # # * * # # *#* * # * *# # * # # * * # * # * # * # 4621 * # * # * * # # 4103 4021 4083 * # * # 4663 * # * # * # * # * # * # * # # * * # * *# # * # # * Below FAL (Below 0.0369 pCi/g) (Below 0.0142 pCi/g) FAL to less than 2 times FAL # * (0.0369 to 0.0737 pCi/g) (0.0142 to 0.0283 pCi/g) 2 times to less than 3 times FAL # * (0.0738 to 0.110 pCi/g) (0.0284 to 0.0425 pCi/g) * # 3 times to less than 4 times FAL # * (0.111 to 0.147 pCi/g) (0.0426 to 0.0567 pCi/g) Greater than 4 times FAL # * (0.148 to x.xxx pCi/g) (0.0568 to x.xxx pCi/g) Likely Remediation Zones Chemical (as of 5/2012) Structures Existing Removed There were no samples which corresponded to the boxed symbol. * * # # 4825 * # # * * # * # * # t. ES * # 4014 * # * # L85 Nuclear Experimentation Reactor Building 4093 * # 4035 * # * # * # 4046 * # * # * # 4064 * # 4641 * # Shield Test Irradiation Reactor Kinetics Experiment #* * # Water Boiler * # Former Building 4073 4036 4625 * # 4037 * # * # * # * # * # * * # # GS t. 11th St. * # * # HGL—Radiological Characterization of Soils in Area IV and NBZ, Santa Susana Field Laboratory—Ventura County, California Figure 4.5 Plutonium-239/240 Round 1 and 2 Surface Soil and Sediment Results Santa Susana Field Laboratory Area IV and NBZ Radiological Study Roads Approximate Drainage Pathways 20-foot elevation contours * # 4027 4024 Subareas * # * # * # Legend TAL (FAL = 0.0142) * # * # 4025 GEL (FAL = 0.0369) * # * # * # * # # * 4010 Plutonium-239/240 * # * # * # * # * # * # * # * # * # 4664 4075 * # * # * # * # * # 4022 * # * # * # 4665 * # Interim Storage Facility Building 4654 Sodium Reactor Experiment Complex * # * # St. * # * # * # # * * # # * * # * # * # # * * # * # * # 10th * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # 4693 * # * # # * * # # * * # * # * # * # * # * # * # * # * # * # * ## * * # * # * # * # * # * # * # * # * # Engineering Test Building * # Former Building 4003 4003 * # * # * # * # * # 4143 * # * # * # * # * # * # * # * # *# # * * # * # * # * # * # * # 4724 * # * # * # # # * * *# # * *# # * * # * # * # * # * # * # * # RMHF Leachfield Hot Oil Sodium Cleaning Facility * # # * 4163 * # * # * # * # # * * # * # * # * # * # * # * # * # ** # # * # * # Former Buildings 4375 and 4875 * # * # 4723 * # * # * # * # Hot Lab - Former Building 4020 * # * # * # # * * * # *# # # * * # * # * * # # # * # * * * # # * # # * # * # * * # * # * *# # * # * # # * # * * # * # * # * # # * * # SRE Dam * # * # * # * # * # * # * # * # * # * # * # * # * # Plutonium Development Facility Building 4055 * # Subarea 8 South * # * # * # * # * # * # * # Hazardous Waste Management Facility Building 4133 * # 4373 Leach Field * # * # * # * # * # * # * # * # Subarea 5D North * # * # * # * # * # * # * # * # * # * # * # * # * # * # Fast Critical Experiment Building 4100 * # * # * # * # Building 4015 * # * # * # Subarea 5C * # * # I St. # * * # * # Building 4019 * # 4874 * # * # * # # * * # * # * # * # * # * # * # * # * # * # Building 4011 *# ## * * * # SRE Pond * # Former Building 4356 4015 * # * # * # 4374 * # 4848 * * # * # # * # * 4373 # * * # # * # * # * # * # # * # * * # J St. 4055 * # Liquid and Gas Radioactive Storage Tanks Subarea 7 Northern Panhandle Building 4006 * # * # # * * # * # * # * # * # # # * * * # * * # # # * # * * # * # * # * * # # * # * # * 4363 # * # * # * # * # # ## * *# *# * # ** * # 4875 * # * # * # * # * # * # * # 17th Street Drainage * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # Inset Subarea 5B G St. * # * # # * # * * # # * # * * *# # # * * # * # * * # # * # * # * # * # # * * # *# # *# * * # * # 4020 * # * * # * # # * # *# * * # *# # * * # * # # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # 4009 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # 22nd St. * # * * # # * # * # * # 4383 * # * # * # s F ir e 4482 4461 * # * # * # Heavy Metal Likely Remediation Zone 4483 4484 4485 24th St. * # * # Arnes 4462 4100 * # * # * # * # 4463 4487 * # * # Former Building 4005 4486 * # * # Former Building 4023 * # * # 4011 F St. 4609 * # * # * # * # * # * # * # * # * * # # * # * # 24th St. * # 4066 4065 * # * # * # Fuel Element Storage Facility * # * # 4626 * # * # * # * # * # * # * # * # * # New Conservation Yard Drainage * # * # * # * # * # 4057 * # * # * # * # 4816 4038 * # Old Conservation Yard 4826 4039 * # * # * # * # * # # * * * * # # # * # * # # * # * 4064 * # # * * # * # * * # *# # # * * # St * # * # h * # * 4023 # * # 4059 * # * # * # * # * # * # * # * # * * # # * # # * * # * # * # t 17 * # * # * # * # G 4042 * # * # * # * # 4006 4356 * # 4040 * # 4035 4046 * ## * * *# # * # * # * # Subarea 6 * # * # * 4014 # * # * # ## * * * # 4362 * # * # * # * # * # * # t. * # * # * # # * * # 4036 * # * # * # ES 4027 4019 * # ## * * * # * # # * * # * # * # * # * # * # * # 4641 4013 * # * # * # # * * # * # # * * ## * * # # * # * * # * # * * # # # * *# *# # *# * 4825 * # 4037 17th St. * # * # * # * # * # S t. * # * # * # * # * # 17th St. * # * # F St. * # * # 4083 4025 * # Empire State Atomic Development Associates (ESADA) 4724 # * *# # * * # * # * # Former Sodium Disposal Facility * # ## * * * # * # * # 4103 4625 * # * # * # # * * # 4663 * # # ** # * # * # 4723 # * 4693 * # * # 4010 * # * # * # * # * # 4021 4075 * # * # * # 11th St. * *# # * # * # * # 4022 4024 * # 4665 4664 * # * # # * * # * * # * ## * # * # * # # * * # * # *# # * * # * # * # * * # # * # h 10t * # * # Sodium Graphite Reactor/ Organic Moderated Reactor Building 4009 # * * # # * * # # * # * * # * ## * * ## * * ## * * # # * * *# # * # # *# * # * # * # * # * * # # * * # *# # * # * # *# # * * * * # # * * # # * # * # * # # * * # * # * # * # * # * # *# # # * * *# # * * *# # * # # * * # * # * # * # * # * 4003 # * # ## * * *# * # * # * # * # 4163 * # * # * # * # * # * # # ** # # * * # * # * # 4143 * # ## * * * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * * # # * # * # * # * # * # # * * * # * * # *# # *# # * # # * **# * # *# # * # # * ** * # # * # # *# * # *# # * * # * # * # * # * *# # *# # * # * * # * # * # * # # * * # * # * # * # Southern California Edison Substation * # * # * # * # * # * # * # * # See Inset Northern Buffer Zone West * # * # * # * # SNAP Experimental Reactor Facility Former Building 4010 * # # * * # * # # * Shield Test Irradiation Reactor * # * # * # * * # # Subarea 8 North * # Subarea 3 * # * # * # * # * # * # Outfall #3 # * * # Notes: FAL - Field action level GEL - GEL Laboratories, Inc KEWB - Kinetics Experiment Water Boiler NBZ - Northern Buffer Zone SNAP - Systems Nuclear Auxiliary Power TAL - Test America Laboratories RMHF - Radioactive Materials Handling Facility pCi/g - picocuries per gram 0 250 ³ 500 Feet U.S. EPA Region 9 1000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\FAL_Plates\ Fig4-5_Pu-239-240_Surface.mxd 12/19/2012 pbillock Boeing 2011, HGL 2012 Northern Buffer Zone East * # * # * # * # Sodium Reactor Experiment (SRE) Complex * # * # * # * # St. 3r d Radioactive Materials Handling Facility (RMHF) Complex * # * # * # * # # * * # * # * # * # Subarea 7 * # * # * # Outfall #3 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * * # # Northern Buffer Zone West * # * # # ** # * # * # * # * # * # * # # * * # * # # ** # # # * * * # * # * # * # * # Subarea 8 North * # * # * # *# # * *# * # * # # * * # * # * # * # * # * # * # * # * ## * * # * # * # * # * # * # * # * # * # * # * # 4010 * # * # * # * # * # * # * # 4724 * # * # *# # * * # * # * # * # * # F St. 4003 # * * # * # # * * # * # *# # *# * * # * # * # * # 4693 * # * # # * * # * # * # * # * # * # * # * # * # * # 4040 * # * # * # 4035 4103 Old Conservation Yard * # * # # * 4083 * # # * 4046 4093 * * # # * ## * 4073 * # * # 4641 * # * # # * * * * # # # * # * # # * # * 4064 * # # * * # * # # * * # # * 4036 4625 4037 * # * # 4027 4024 G # * * # * # * # * # * # S t. Engineering Test Building Former Building 4003 11th St. * # * # # * * # *# # * * 4023 # # * * # 12 th S t. * # * # 4356 4026 * # * # * # * # 4826 * # * # 4816 Subarea 5A * # # * t 17 * # * # h * # St . 4057 * # * # 4626 Building 4029 * # * # * # ## * ** # # * 4038 L85 Nuclear Experimentation Reactor - Building 4093 * # t 20 * # * # h * # 4062 St t 18 . * # * # h St . * # Kinetics Experiment Water Boiler - Former Building 4073 * # * # 4066 4065 * # * # * # Former Building 4023 * # * # * # * # * # * # * # 4609 4486 4885 * # * # * # * # * # * # 4463 4462 4482 4487 # * # * * # * # * # * # * # # * * # # * * * # # * # * # * # Rd. * # * # * # * # * # * # * # # * * # H St * # * # * # * # 4814 * # * # # * * # * # * # 4314 * # * # * # * # * # * # * # # * * # * # # # * * * # *# # *# * * # 4318 * # * * # # * # * # * 4425 # # * * # * # * * # # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # # * * # * # * # * # * # * # # * * # 4015 * # * # * # * # * # # * * # # * * # * # * # # * * # * # * # * # * # * # * # * # * # * # * # * # * # * # Radioactive Materials Handling Facility Complex Outfall #3 Pond Dredge Area * # Former Buildings 4173/4865 * # * # * # # * * # # * * * # # # * ** * # # # * # * # * # * # * # * # * # * # * # * # 4103 4021 4083 4663 * # * *# # * # * # TAL (FAL = 0.0142) (Below 0.0369 pCi/g) (Below 0.0142 pCi/g) FAL to less than 2 times FAL # * (0.0369 to 0.0737 pCi/g) (0.0142 to 0.0283 pCi/g) 2 times to less than 3 times FAL # * (0.0738 to 0.110 pCi/g) (0.0284 to 0.0425 pCi/g) 3 times to less than 4 times FAL # * (0.111 to 0.147 pCi/g) (0.0426 to 0.0567 pCi/g) Greater than 4 times FAL # * (0.148 to x.xxx pCi/g) (0.0568 to x.xxx pCi/g) CL to FAL * # Subareas Likely Remediation Zones Chemical (as of 5/2012) * # # * * * ## * # # * * # *# * # * # * # # * * # Structures Existing Removed There were no samples which corresponded to the boxed symbol. * # 4014 * # * # * # * # 4046 * # * # * # 4064 * # * # * # * # * # * # * # 4036 4625 * # 4037 * # * # Kinetics Experiment Water Boiler Former Building 4073 * # * # * # GS 4027 4024 * # * # * # * # * # HGL—Radiological Characterization of Soils in Area IV and NBZ, Santa Susana Field Laboratory—Ventura County, California Figure 4.6 Plutonium-239/240 Round 1 and 2 Subsurface Soil and Sediment Results Santa Susana Field Laboratory Area IV and NBZ Radiological Study Approximate Drainage Pathways Notes: CL - Critical level FAL - Field action level GEL - GEL Laboratories, Inc KEWB - Kinetics Experiment Water Boiler NBZ - Northern Buffer Zone SNAP - Systems Nuclear Auxiliary Power TAL - Test America Laboratories RMHF - Radioactive Materials Handling Facility pCi/g - picocuries per gram 0 250 ³ 500 Feet t. 11th St. * # Roads 20-foot elevation contours * # 4035 4641 4025 GEL (FAL = 0.0369) * * # # * # # * * # * # t. ES * # 4010 Plutonium-239/240 * # * # * # Legend * # * # * # # * Shield Test Irradiation Reactor * # St. * # * # 4621 * # * # * # 10th * # * # * # L85 Nuclear Experimentation Reactor Building 4093 * # * # * # * # * # * # # * * # * # * # 4664 4075 * # * # * # # * * # * # * # * # * # * # 4022 * # * # * *# # * # * # # * * # * # * # * # * # * # 4693 * # 4665 * # * # * # * # * # * # * # # * * # * # * # * # Subarea 5D South * # * # # * # # * # * * 4825 Interim Storage Facility Building 4654 * # # * * # * # * # * # Sodium Reactor Experiment Complex * # * # # * * # * # * # *# # * * # * # * # * # * # * # 4003 * # * # Engineering Test Building * # Former Building 4003 * # * # * # * # * # * # * # * # * # * # * # * # * # * # Hot Oil Sodium Cleaning Facility * # * # * # * # * # * # 4163 * # 4143 * # * # # * *# * # * # * # * # * # * # * ## * * * # # *# * # # * * * # * # # *# # * * # * # * # * # * # * # * # * # * # * # 4724 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # Site 4614 RMHF Holdup Pond/Catchment * # Basin * # * # # * * * # # * # * # * # * # * # Former Buildings 4375 and 4875 * # * # * # * # RMHF Leachfield * # * # * # * # * # * # * *# # * # * # * # * # * # Hot Lab - Former Building 4020 * # * # * # * # * # Former Building 4353 * # * # * # 4723 * # * # * # * # * # * # * # # * Hazardous Waste Management Facility Building 4133 Plutonium Development Facility Building 4055 * # Subarea 8 South * # # * * # * # 4373 Leach Field * # * # * # * # # * * # * # SRE Dam * # * # * # * # * # * # * # * # * # * # * # * # * # * # Subarea 5D North * # * # * # * # * # * # * # * # * # * # * # Fast Critical Experiment Building 4100 * # * # * # * # * # * # * # Building 4015 4353 I St. * # * # # * * # Subarea 5C * # * # * # * # * # * # * # * # * # * # * # * # * # * # Building 4019 * # 4874 SRE Pond * # Building 4011 *# ## * ** # * # Liquid and Gas Radioactive Storage Tanks * # Former Building 4356 * # 4374 * # * # 4848 * # * * # # * # * 4373 # * * * # # * # # * # * # * # * # * # * # J St. 4055 Subarea 7 Northern Panhandle Building 4006 * # * # * # # * * # * # * # * # 17th Street Drainage * # * # * # * # * # * # * # # * * # * # * # * # # * * # * # * # * # * # * # # * * * # # * * # # * * # * # # * # * # * # # * * # * # # * * # * 4363 # * # * # # * * # * # # * * # *# # *# *# # ** * # 4875 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # Subarea 5B G St. * # * # # * # * * # # * # * * *# # # * * # * # * * # # * # * # * # * # # * * # *# # *# * * # * # 4020 * # * * # * # # * # *# * * # *# # * * # * # # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # 4009 * # * # * # * # # * * # * # * # * # 22nd St. * # * # * * # # * # 4383 * # 24th St. * # * # Inset 4461 * # * # * # Heavy Metal Likely Remediation Zone 4483 4484 4485 4100 * # * # Former Building 4005 * # * # * # * # 4011 F St. 24th St. * # Fuel Element Storage Facility * # 4005 4039 * # New Conservation Yard Drainage * # 4006 4059 * # # * * # * # * * # # * # * # 4042 * # * ## * * # * # * # * # * # * # Subarea 6 * # * # # * * # * 4014 # S t. * # * # s F ir e * # * # * # # * * # * # # * * # * # ## ** # *# * E # * * # * # * # 4013 4362 Arnes * # * # * # * # * # * # * # 4019 * # * # * # * # * # * # * # * # 4163 * # * # * # * # * # * # 17th St. * # * # * # # * *# # * * # 4825 4022 * # * # * # # * * # 4723 * # 4021 4663 * # * # * # * # * # * # * *# # # * * *# * *# *# *# # * # *# * # *# # * 4143 * # * # # * # * # * # * * # * # # * # 17th St. * # * # * # * # * # * # * # * # * # # * SRE Dam 4665 4664 * # 4025 * # * # # * * * # # * # * # 4654 * ## * *# # * * # * # * * # # # * * # * # *# # * # * * # # * S t. * # * # * * # # * # * # # * * # * # * # * # * # h 10t * * # # * # * # * # # * 4075 # * * # *# # *# * # *# * * * # # *# *# # * 4614 4621 * # # * * # * # * *# # * # * # * # * # * # *# # * # * # * *# # *# ** # * # * # * # *# # * * 4028 # * # * # * # * # * # # * * # * # * * # # * # * # * # # * * # *# # *# * * # * # * # * # * # * # * # * # *# # *# * *# #* ** # * * # # *# *# # * # * # * * # # * * # # * # # 4133 ** # # * * # * # * # * # * # * # * # # * * # # * * # # * * # * # * # # * * # * # * # * # * # * # * # * # # * * # * # * # * # * # Empire State Atomic Development Associates (ESADA) Southern California Edison Substation * # * # * # * # Subarea 3 * # * # * # Former Sodium Disposal Facility * # * # * # SNAP Experimental Reactor Facility Former Building 4010 Sodium Graphite Reactor/ Organic Moderated Reactor Building 4009 * # * # * # * # Building 4009 Leachfield * # * # * # # * See Inset Shield Test Irradiation Reactor 4056 Landfill * # * # * # # * * ## * * # * # * * # # * # * # * # * # # * * # * # U.S. EPA Region 9 1000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\FAL_Plates\ Fig4-6_Pu-239-240_Subsurface.mxd 12/19/2012 pbillock Boeing 2011, HGL 2012 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # Northern Buffer Zone East * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # Sodium Reactor Experiment (SRE) Complex * # * # * # St. 3r d * # Radioactive Materials Handling Facility (RMHF) Complex * # * # * # * # * # * # # * * # * # * # Subarea 7 * # * # * # * # * # * # # # * ** # * * # *# *# # *# # * * # * # * # * * # # * # * # * * # * # * * # *# # *# # * # # * # * **# # * # * # * # # * ** * # # * # * # *# * # * # # *# # * * # * # * # * * # # * * # # * # * # *# * * # # *# *# * # # *# * *# * * # # *# *# * # * # * *# # * # *# * 4143 *# # * # *# * # *# # * * # * # * # * # * # * * *# # * # * # * # * *# # *# # *# # * # * * # * # * # * 4133 *# # # * *# *# # * # #* * * # * # * # * # * *# * # *# # # * * ** # # # # * * # * # * # * # * # * # Subarea 8 North * # * * # # * ## ** # * # * # * # * # * # * # * # * # 4056 Landfill * # * # * # * # Building 4009 Leachfield * # * # * # * # * # * # * # * *# # * # * # Former Sodium Disposal Facility * # * # * # Empire State Atomic Development Associates (ESADA) 4356 * # 4059 * # 4057 # * * * # # * # St 4062 . t 18 * # * # h St * # * # * # * # * # # * *# # * * # # * * # * # * # * # * # * # * # * # * # * # * # * # s F ir e Rd. * # * # * # * # * # * # * # * # * # # * * # * # * # * # ## * *# # * * H St * # * # * # * # * # 4314 * # * # * # * # * # 4814 * # * # * # * # * # # # * * * # * # *# # *# * * # * # 4318 # * * # # * * * # * # # * # 4425 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * * # # * # * # * # # * * # # * * # * # * # * # * # # * * # Building 4029 L85 Nuclear Experimentation Reactor - Building 4093 Kinetics Experiment Water Boiler - Former Building 4073 * # Former Building 4023 * # Former Building 4005 * # Heavy Metal Likely Remediation Zone * # 4482 * # Inset Subarea 5B 4374 * # 4848 * * # * # # * # * 4373 # * * # # * # * # * # * # # * # * * # J St. 4055 * # * # * # * # * # 4353 * # # * * # * # * # * # * # * # * # * # * # * # Subarea 5D North * # * # * # * # * # * # * # * # Radioactive Materials Handling Facility Complex Plutonium Development Facility Building 4055 * # * # * # 4373 Leach Field * # * # Subarea 8 South * # * # Former Buildings 4375 and 4875 * # Pond Dredge Area Former Buildings 4173/4865 * # * # * # * # * # * # * # Site 4614 RMHF Holdup Pond/Catchment * # Basin * # * # * # * # * # * # * # * # * # * # * # * *# # * # * # * # * # * # * # * *# # 4621 * # * # * # * # * # * # * # * # Interim Storage Facility Building 4654 # * 4103 4083 Below FAL * # (Below 0.0252 pCi/g) (Below 0.0228 pCi/g) FAL to less than 2 times FAL # * (0.0252 to 0.0503 pCi/g) (0.0228 to 0.0455 pCi/g) 2 times to less than 3 times FAL # * (0.0504 to 0.0755 pCi/g) (0.0456 to 0.0683 pCi/g) 3 times to less than 4 times FAL # * (0.0756 to 0.100 pCi/g) (0.0684 to 0.0911 pCi/g) Greater than 4 times FAL # * (0.101 to x.xxx pCi/g) (0.0912 to x.xxxx pCi/g) Subareas Likely Remediation Zones Chemical (as of 5/2012) Structures Existing Removed There were no samples which corresponded to the boxed symbol. * # * # * # * * # # * # 4825 * # # * * # * # * # t. ES * # * # Shield Test Irradiation Reactor * # * # L85 Nuclear Experimentation Reactor Building 4093 * # 4035 * # * # * # 4046 * # * # * # 4064 * # Kinetics Experiment #* * # Water Boiler * # Former Building 4073 4036 4625 * # 4014 * # * # * * # # * # * # * # * # 4037 * # * # # * * # * * # # GS 4027 t. 11th St. * # * # HGL—Radiological Characterization of Soils in Area IV and NBZ, Santa Susana Field Laboratory—Ventura County, California Figure 4.7 Cobalt-60 Round 1 and 2 Surface Soil and Sediment Results Santa Susana Field Laboratory Area IV and NBZ Radiological Study Roads Approximate Drainage Pathways 20-foot elevation contours * # * # * # * # * # 4025 TAL (FAL = 0.0228) * # * # 4641 4010 GEL (FAL = 0.0252) * # * # * # * # * # # * ## * * * # Cobalt-60 * # * # * # * # 4024 Legend Sodium Reactor Experiment Complex * # * # * # * # # * * # * # * # * # 4693 * # * # * # * # * # # ** # * # * # * # * # 4663 * # Engineering Test Building * # Former Building 4003 4003 * # * # * # * # * # * # 4021 * # * # * # # * * # 4163 * # * # * # # # * * * # * # * # * # 4664 4075 * # 4724 * # * # * * # # Hot Oil Sodium Cleaning Facility * # * # * # * # * # # * * # * # * ## * 4143 # * * *# # * # * # St. * # * # * # * # 4723 10th * # # * * # *# # * *# * # # * *# *# # * * # * # * # 4022 * # # * * # * # * # 4665 * # * # * * # # # * * # # * # # * * * # * # * # # * * # # * * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # # * * # *# # * * # * # * # * # * # SRE Dam * # * # * # * # * # * # * # * # * # * ## * * # * # * # * # * # *# # * * # * # * # * # * # * # * # * # * # * # * # * # # * *# # * * # Subarea 5D South * # * # * # * # * # * # * # * # # * * # * # * # # * * # * *# # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * * * # *# ## * # # * * # * # * # * # * # # * * * # *# # # * * # * # * * # # * # # * * * # # * # # * # * # * # * * # * # # * * *# # * # # * * # * # # * # * * # * # * # # * * # # * # * * # # * * * # # * # # * * *# *# * # # * *# # * # * # * # * # * # RMHF Leachfield * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * ## * * # * # Hot Lab - Former Building 4020 * # * # * # Outfall #3 Former Building 4353 * # * # Hazardous Waste Management Facility Building 4133 * # * # * # * # * # * # # * * # # * * # # * Fast Critical Experiment Building 4100 * # * # * # # * * # * # * # * # * # * # Building 4015 * # * # * # * # Subarea 5C * # * # * # * # * # * # * # * # * # * # * # # * * *# # * # * # * # Building 4019 * # * # * # * # # * * # # * * # * # * # Building 4011 * # I St. * # * # SRE Pond * # * # * # * # * # * # Former Building 4356 * # 4874 Liquid and Gas Radioactive Storage Tanks Subarea 7 Northern Panhandle Building 4006 4015 * # * # # * 17th Street Drainage * # * # * # * # * * *# # # # * * # * # * # # * * # * # *# # *# * * # * # * # # * * # * # * # * # * # # # * * * # * * # # # * # * * # * # * # * * # # * # * # * 4363 # * # * # * # * # * # * # * # * ## ** # # * *# 4875 # * * # * # * # * ## * ** # *# # * * # # # * * # * # Subarea 5A * # * # G St. # * * # # * * # * # * # * # * # * # 4483 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # ** # * ## * * # # # * * # # * # * * ## * * # # * * # * # * * # # * # * # * # * # # * * # *# # *# * * # * # 4020 * # * * # * # # * # *# * * # *# # * * # * # # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # 4009 * # * # * # * # * # * # * # 4383 * # * # * # * # * # * # * # * # * # Fuel Element Storage Facility * # 4461 * # * # * # * # * # 4484 4485 * # * # Arnes 4462 * # * * # # * # * # * # * # * # * # * # * # 4463 4100 * # * # * # * # * # 4487 * # Engineering Test Building Former Building 4003 * # * # 4011 22nd St. * # * # 24th St. * # 4885 * # * # * # 4486 * # * # * # * # * # *# # *# * 4609 * # S t. * # * # F St. 24th St. * # # * * # * # * # * # * # 4066 4065 * # * # * # New Conservation Yard Drainage * # * # * # * # * # * # * # * # * # * # . * # * # Old Conservation Yard * # h * # * # S t. * # # * * # t 20 * # * # * # * # * # * # * # * # * # * # 4626 4038 * # * # * # # * * # * # # * * # * # * # * # * # * # *# # ** # ## * * * # * # * * # # * # * # * # * # * # . * # * ## * * # * # * # * # * # * # # * * # * # * # * # # * * # * # * # * # * # * # * # * # * # 4816 4039 * # * # 4046 * # * * # * # # # * * # * * # # * # * # * # # * # * 4064 * # # * * # * # * * # *# # *# * # * # *# # *# * * # * # * # * # St * # 12 th * # * # * # * # * # Subarea 6 * # h * # * # * # 4035 * # * # * # * # 4040 * # * # # * * # * # * # # * * # * 4014 # S t. * # 4826 * # * # * # * # * # * # * # * # * # ## * * * # * # 4026 * # E * # t 17 * # * 4005 ## * * * # # * * # # * # # * 4006 * # * # * 4023 # 4042 * # 4362 * # * # 4825 4093 * ## * * *# # * # 4019 * # * # * # # * * # * # # * * # # * * ## * * # # * # * * # * # * * # # # * *# *# # *# * * # * # # * * # * # * # 17th St. * # * # * # * # G * # 4013 * # # * 4693 F St. # * * * # # 4027 * # # * 17th St. * # * # * # * # * # ## * * * # * # * # * # # * * # 4037 * # * # * # 4036 * # * # * # * 4003 # * # * # * # * # # # * * * *# *# # # * * *# # *# * # 4641 4025 * # * # * # * # * # 4083 4010 * # * # * # * # 11th St. * # * # * # # * 4073 ## * * # * * # # * * # * # 4024 ## * * * # * # * *# # # * * # * # * # * # 4103 4625 * # * # * # * # * # * # 4724 * # 4022 * # # * * # * # 4163 # * * # * # 4021 * # * # * # * # SRE Dam * # * # # * 4663 * # # ** # * # * # S t. Sodium Graphite Reactor/ Organic Moderated Reactor Building 4009 * # * # * # * # h 10t * # * # * # # # * * # # * * # *# # ## ** * * * *# 4654 # * # * *# # * * # * # * # # * # * # * # *# # * # * # # * # * # * # *# # * # * * * # * # *# * # * * *# # *# * # * # * # # # * * # * * * # # # ** * # ## * *# # * *# # * # * * * # *# # # * * # 4665 * # * *# * # *# # * # 4664 * # # * *# * # * # # * * # * # 4723 * # # # * * * * *# # * # * # # *# # * # * # *# * # *# * # * # * # * * # 4075 * # * # *# * # * # *# # # # * * * * # # *# # * # # * * 4614 4621 * # * * * # # # * * # * # * # * # * # * # * # # * * # * # * # 4028 * # * # * # # * * # * # * # * # * # * # * # * * # # * # * # * # * # * # * # # * * # * # * *# # * # # * # # * * * * # * # *# * # # ** # * # # * # * * # # * # * # * # * # # * * # Northern Buffer Zone West Southern California Edison Substation * # * # * ## * * # * # * # * # * # * # See Inset SNAP Experimental Reactor Facility Former Building 4010 * # * # * # # * * # * # * # # * * # * # * # * # * * # # Shield Test Irradiation Reactor * # Subarea 3 * # * # * # * # * # * # Outfall #3 # * * # Notes: FAL - Field action level GEL - GEL Laboratories, Inc KEWB - Kinetics Experiment Water Boiler NBZ - Northern Buffer Zone SNAP - Systems Nuclear Auxiliary Power TAL - Test America Laboratories RMHF - Radioactive Materials Handling Facility pCi/g - picocuries per gram 0 250 ³ 500 Feet U.S. EPA Region 9 1000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\FAL_Plates\ Fig4-7_Co-60_Surface.mxd 12/19/2012 pbillock Boeing 2011, HGL 2012 Northern Buffer Zone East * # * # * # * # Sodium Reactor Experiment (SRE) Complex * # * # * # * # St. 3r d Radioactive Materials Handling Facility (RMHF) Complex * # * # * # * # # * * # * # * # * # Subarea 7 * # * # Outfall #3 * # * # * # * # * # * # * * # # * # * # * # * # * # ** # ## * * * # ## *# * * *# # * # * *# # # * * # * # *# # * # * # ** # * # * # * # * ## ** # * # * # * # * # * # 4056 Landfill * # * # * # * # * # * # * # * # * # 4010 * # * # * # # * * # 4723 * # * # 4724 * # * # * # * # * # * # * # Empire State Atomic Development Associates (ESADA) 4693 * # # * * # * # * # # * * # * # # * * # * # ## ** # *# * # * * # * 4014 # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # 4040 * # * # * # * * # * # # # * * # * * # # * # * # * # # * # * 4064 * # * # # * * # * # * # S t. * # * # # * * # * # * # F St. * # * # # * * # * # * # * # # * * # * # * # * # * # # * * # * *# # * # * # * ## * 4356 * # * # * # * # Old Conservation Yard * # * # 12 th * # * # * # # # * * * # * # S t. * # Fuel Element Storage Facility * # * # * # * # * # * # 4816 Subarea 5A t 17 h * # St . * # * # 4626 * # Building 4029 * # * # * # 4038 L85 Nuclear Experimentation Reactor - Building 4093 * # * # h 4062 St t 18 . * # t 20 * # * # * # * # h St . * # 4066 4065 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # 4609 4486 4885 * # * # * # # * *# # * * # # * * # * # 4463 # * # * * # * # * # 4383 * # s F ir e Rd. * # * # * # * # * # * # * # * # * # # * * * # ## * * *# # * # * # H St * # * # * # * # * # 4814 * # * # # * * # * # 4314 * # * # * # * # * # * # # # * * * # *# # *# * * # 4318 * # * * # # * # * # * # * 4425 # # * * # * # * * # # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * *# # *# * * # * # * # * # * # * # * # * # * # * # # * # * * # # * * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # Hazardous Waste Management Facility Building 4133 Radioactive Materials Handling Facility Complex Plutonium Development Facility Building 4055 * # * # * # Former Buildings 4375 and 4875 * # Pond Dredge Area * # Former Buildings 4173/4865 * # * # * # # * * # * # * # Subarea 5D South * # # * * * # # # * ** * # # # * # * # 4614 * # * # * # * # * # * * # # * # * # * # * # * # * # * # * # * # * * # # 4654 * # * # # * * # * # * # * # * # Shield Test Irradiation Reactor ## * * * # * # * # 4621 GEL (FAL = 0.0252) Below FAL * # TAL (FAL = 0.0228) (Below 0.0252 pCi/g) (Below 0.0228 pCi/g) FAL to less than 2 times FAL # * (0.0252 to 0.0503 pCi/g) (0.0228 to 0.0455 pCi/g) 2 times to less than 3 times FAL # * (0.0504 to 0.0755 pCi/g) (0.0456 to 0.0683 pCi/g) 3 times to less than 4 times FAL # * (0.0756 to 0.100 pCi/g) (0.0684 to 0.0911 pCi/g) Greater than 4 times FAL # * (0.101 to x.xxx pCi/g) (0.0912 to x.xxxx pCi/g) Subareas Likely Remediation Zones Chemical (as of 5/2012) 4103 Structures Existing Removed There were no samples which corresponded to the boxed symbol. * # * # * # * # * # * # * # * * # # * # * # # * * # * # * # t. ES * # 4021 * # 4083 4663 * # 4073 * # * *# # * # * # * # * # * # 4046 * # * # * # * # 4028 4036 4625 * # 4037 * # 4064 * # 4641 * # * # * # * # * # * # * # * # * # * # * # 4014 4035 L85 Nuclear Experimentation Reactor 4093 Building 4093 * # Kinetics Experiment Water Boiler Former Building 4073 * # * # * # * # * # * # GS 4027 4024 * # * # * # * # * # HGL—Radiological Characterization of Soils in Area IV and NBZ, Santa Susana Field Laboratory—Ventura County, California Figure 4.8 Cobalt-60 Round 1 and 2 Subsurface Soil and Sediment Results Santa Susana Field Laboratory Area IV and NBZ Radiological Study Approximate Drainage Pathways Notes: FAL - Field action level GEL - GEL Laboratories, Inc KEWB - Kinetics Experiment Water Boiler NBZ - Northern Buffer Zone SNAP - Systems Nuclear Auxiliary Power TAL - Test America Laboratories RMHF - Radioactive Materials Handling Facility pCi/g - picocuries per gram 0 250 ³ 500 Feet t. 11th St. * # * # Roads 20-foot elevation contours * # 4825 * # 4025 Cobalt-60 # * * # * # * # 4010 Legend * # 4693 * # * # * # * # * # # * # # * # * * 4665 * # * # # * * * ## * # # * * # *# # *# * * # * # # * * # * # * # Interim Storage Facility Building 4654 * # * # * # Sodium Reactor Experiment Complex * # * # Engineering Test Building * # Former Building 4003 * # * # * # * # # * * # * # * # 4003 * # * # # * * # # * * # * # 4664 4075 * # * # * # * # * # *# # * * # * # St. * # * # * # * # * # * ## * * # * # * # * # # * # * 4163 * # * # * # * # Hot Oil Sodium Cleaning Facility * # * # 10th * # * # 4022 * # * # # * * # * # # * * # * # * # # # * * * # * # * # * # * # * # * # * # * *# # * # * # # * * # * # # * * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * ## * * * # # *# * # # * * * # * # # *# * * # # * # * # # * * # * # * * * # *# ## * # # * * # * # * # * # * # 4133 * # * # * # * # * # 4724 * # * # # * * # * # * # * # * # * # * # * # * # * # * # * # * # * * # # * # * # * # * # * # * # * # * # * # # * * * # # * # * # * # * # * # * # * # * *# # * # * # * # * # * # * # * # * # # # * * * # 4723 * # 4143 * # # * * # * # * # * # * # * # RMHF Leachfield * # * # SRE Dam SRE Dam * # * # *# # * * # * # Site 4614 RMHF Holdup Pond/Catchment * # Basin * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * ## * * * # # * # * # * # * # * # Hot Lab - Former Building 4020 * # * # * # * # Outfall #3 Former Building 4353 * # # * * # # * * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # 4373 Leach Field * # * # * # * # * # * # * # * # * # Subarea 5D North * # Subarea 8 South * # * # * # * # * # * # * # * # * # Fast Critical Experiment Building 4100 * # * # * # * # * # * # Building 4015 4353 * # * # * # * # * # # * * # # * * # Subarea 5C * # * # * # * # * # * # * # * # I St. * # * # Building 4019 * # 4874 SRE Pond * # Building 4011 * # * # * # *# # *# * * # * # * # * # * # * # * # * # # * * # * # * # # * * # 4015 Liquid and Gas Radioactive Storage Tanks * # Former Building 4356 * # 4374 * # * # 4848 * # * * # # * # * 4373 # * * * # # * # # * # * # * # * # * # * # J St. 4055 Subarea 7 Northern Panhandle Building 4006 * # * # * # * # * # # * * # * # * # * # * # * # # * * * # # * * # # * * # * # # * # * # * # # * * # * # # * * # * 4363 # * # * # # * Inset * # * # # * 17th Street Drainage * # * # * * * # ## ** # # *# 4875 # * * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # # * * # * # * # * # * # * # * # * # ** # * ## * * # # # * * # # * # * * ## * * # # * * # * # * * # # * # * # * # * # # * * # *# # *# * * # * # 4020 * # * *# # * * # # * # *# * * # *# # * * # * # # * # * # * # * # * # * # * # * # * # 4009 * # * # * # * # * # G St. 22nd St. * # * # * # Subarea 5B * # * # * # * # * # * # 4482 * # * # Arnes Heavy Metal Likely Remediation Zone 4483 * # * * # # * # Former Building 4005 * # 4461 24th St. * # * # Former Building 4023 * # 4484 4485 4487 * # * # * # 4462 4100 * # * # * *# # * # * # * # 24th St. * # * # * # # * * # 4011 F St. Kinetics Experiment Water Boiler - Former Building 4073 * # * # * # * # Engineering Test Building Former Building 4003 * # S t. * # 4057 * # New Conservation Yard Drainage * # * # # * * # * # * # * # * # * # * 4005 ## * * * # # * * # # * # # * * # * # * # # * * # 4826 4039 * # * # * # 4026 4059 * # * # * # * * # # * # * # * # * # Subarea 6 * # * # # * * # 4042 * # * # * # * # * # 4006 * # * # * # * # * # * # 4013 4362 * # * # * # * # G 17th St. 4019 * # * # 11th St. * # * # # * * # *# # * * 4023 # # * * # * # * # * # * # * # 4027 * # * # * *# # # * * # * # 4036 # * * # * # * # * # * # # * * # # * * # * # * # 4641 4037 * # # * * # # * * # * # * # * # # * * *# # *# * # * * # # * # * # * # * # * # * # # * 4046 4083 * ## * * # * # E * # # * * # * # * # * # * # * # # * 17th St. * # * # 4021 4024 * # * # * # * # * # * # 4625 * # Southern California Edison Substation * # * # * # * # * # 4035 4103 * # * # * # * # 4022 4663 * # * # * # 4825 * # * # * # * # * # 4665 4664 * # 4025 * # * # * # * # * # # * * # # * # * * # # * * # * # * # * # # * * * # # * # * # * # # * *# * # # * * * # # * # * * # * # # * # * # *# # * # *# * # * * # *# * *# # * * # * # # * * # * # # * # **# # * # * # # * * * # * # # * *# * # # * # # *# * * # * # * # * # * # * 4163 *# # * # *# * * # # *# * * # *# *# # * # * # # * *# # * # * * * # * # * *# * # * *# # * # # * ## * *# # *# * *# # * 4143 * # *# # *# * # # * *# * # # * # 4003 *# # * * * # * # * # * # * * # * # * # # * # # * # * * # * # * # * *# # * # * # * # * * # * # # *# # *# * * *# # * # * # * # # * * # * # * # * # * # * # * # # ## ** * # # * * *# # * # * * # *# * * # *# # * # * *# # ## * * # * * * # # * # *# # * * # * # * # * # ## * * * # * # * # * # * # S t. * # * # Former Sodium Disposal Facility * # * # # * * * # * # # *# * # * # # * * # # * h 10t * # * # * # * # # * # * ** # * # * # * # # * # *# # * # * * # 4075 # * * # *# *# * # * # # *# * * * # # # # * *# *# # * * # * 4621 * # * # # * * # * # * *# # * # * # * # * # # * * # *# # * # * # * *# # *# ** # * # * # * # * # *# # * * # * # * # * # * # Building 4009 Leachfield * # # * * # * # * # * # Subarea 3 * # * # * # * # * # * # * # Northern Buffer Zone West * ## * * # * # * # * # # * * # SNAP Experimental Reactor Facility Former Building 4010 * # * # * # * ## * * # * # * # # * # # * * * # # # * * * # # * * # *# * # * # * # # * * # * # # * * # Subarea 8 North * # * # # * See Inset Shield Test Irradiation Reactor Sodium Graphite Reactor/ Organic Moderated Reactor Building 4009 * # * # * # # * * ## * * # * # * * # # * # * # * # * # # * * # * # U.S. EPA Region 9 1000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\FAL_Plates\ Fig4-8_Co-60_Subsurface.mxd 12/19/2012 pbillock Boeing 2011, HGL 2012 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # Northern Buffer Zone East * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # Sodium Reactor Experiment (SRE) Complex * # * # * # St. 3r d * # Radioactive Materials Handling Facility (RMHF) Complex * # * # * # * # * # * # # * * # * # * # Subarea 7 * # * # * # * # * # * *# * # *# # # * * ** # # # # * * # * # * # * # * # * # Subarea 8 North * # * * # # * ## ** # * # * # * # * # * # * # * # * # 4056 Landfill * # * # * # * # Building 4009 Leachfield * # * # * # * # * # * # * # * # * # Former Sodium Disposal Facility * # * # * # * # * # * # * # 4626 * # 4885 # * *# # * * # # * * # * # 4100 * # * # * # * # * # Arnes * # s F ir e Rd. * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # ## * *# # * * * # * # * # 4314 * # H St * # * # * # 4814 * # * # * # * # # * * # * # * # * # * # * # # # * * * # * # *# # *# * * # * # 4318 # * * # # * * * # * # # * # 4425 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * * # # * # * # * # # * * # # * * # * # * # * # * # * # * # * # * # Building 4029 * # L85 Nuclear Experimentation Reactor - Building 4093 Kinetics Experiment Water Boiler - Former Building 4073 * # * # * # * # * * *# # # # * * # * # * # # * * # * # Former Building 4023 * # Former Building 4005 * # * # Heavy Metal Likely Remediation Zone * # 4383 * # Inset Subarea 5B 4374 * # 4848 * * # * # # * # * 4373 # * * # # * # * # * # * # # * # * * # J St. 4055 * # * # * # 4353 * # * # # * * # * 4353 # * # * # # * * # * # * # * # * # * # Fast Critical Experiment Building 4100 * # * # * # * # * # * # * # * # * # * # Radioactive Materials Handling Facility Complex Plutonium Development Facility Building 4055 * # * # * # 4373 Leach Field * # * # Subarea 8 South * # Subarea 5D North * # * # * # * # Former Buildings 4375 and 4875 * # Pond Dredge Area Former Buildings 4173/4865 * # * # * # * # * # * # * # Site 4614 RMHF Holdup Pond/Catchment * # Basin * # * # * # * # * # * # * # * # Subarea 5D South * # * # * # * # * # * # * # * *# # * # * # * *# # * # # * * # 4621 * # * # * # * # * # * # Interim Storage Facility Building 4654 * # # * * # 4103 4083 Below FAL * # (Below 0.670 pCi/g) (Below 0.0459 pCi/g) FAL to less than 2 times FAL # * (0.0670 to 0.133 pCi/g) (0.0459 to 0.0917 pCi/g) 2 times to less than 3 times FAL # * (0.134 to 0.200 pCi/g) (0.0918 to 0.137 pCi/g) 3 times to less than 4 times FAL # * (0.201 to 0.267 pCi/g) (0.138 to 0.183 pCi/g) Greater than 4 times FAL # * (0.268 to x.xxx pCi/g) (0.184 to x.xxx pCi/g) Subareas Likely Remediation Zones Chemical (as of 5/2012) Structures Existing Removed There were no samples which corresponded to the boxed symbol. * # * # * # * # * * # # * # 4825 * # # * * # * # * # t. ES * # * # * # L85 Nuclear Experimentation Reactor Building 4093 * # 4035 * # * # * # 4046 Shield Test Irradiation Reactor * # 4064 * # * # * # * * # # * # * # * # * # Kinetics Experiment #* * # Water Boiler * # Former Building 4073 4036 4625 * # * # * # * # * # 4014 * # 4641 4037 * # * # # * * # * * # # GS 4027 t. 11th St. * # * # HGL—Radiological Characterization of Soils in Area IV and NBZ, Santa Susana Field Laboratory—Ventura County, California Figure 4.9 Europium-152 Round 1 and 2 Surface Soil and Sediment Results Santa Susana Field Laboratory Area IV and NBZ Radiological Study Roads Approximate Drainage Pathways 20-foot elevation contours * # * # * # * # * # * # 4025 TAL (FAL = 0.0459) * # * # * # * # * # # * 4010 GEL (FAL = 0.670) * # * # * # * # * # # * Europium-152 Sodium Reactor Experiment Complex * # * # * # * # * # 4024 Legend 4693 * # * # * # * # * # Engineering Test Building * # Former Building 4003 * # # ** # * # * # * # * # * # * # 4003 * # * # * # * # 4663 * # 4163 * # * # * # # # * * * # * # * # 4021 * # 4724 * # * # * * # # Hot Oil Sodium Cleaning Facility * # * # * # * # * # # * * # * # * ## * 4143 # * * *# # * # * # St. * # * # * # * # * # * # 4723 * # * # 4664 4075 * # * # 10th # * * # *# # * *# * # # * *# *# # * * # * # * # * # * # * # 4022 * # # * * # * # * * # # # * * # # * * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # # * # # * * * # 4665 * # # * * # * # * # * # * # # * * # *# # * * # * # * # * # * # # * *# # * * # * # * # * # * # * # * # * # * # * # * ## * * # * # SRE Dam * # * # * # * # * # *# # * * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * *# # * # * # * # * # * # * # * # * # * # * * * # *# ## * # # * * # # * * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * * # *# # # * * # * # * * # # * # # * * * # # * # # * # * # * # * * # * # # * * *# # * * # # # * * # * # # * # * * # * # * # # * * # # * # * * # # * * * # # * # # * * *# *# * # # * *# # * # * # * # * # * # RMHF Leachfield * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # # * * # # * * # * ## * * # * # Hot Lab - Former Building 4020 * # * # * # Outfall #3 Former Building 4353 * # * # Hazardous Waste Management Facility Building 4133 * # * # * # # * * *# # * # * # * # * # * # * # Building 4015 * # * # * # * # Subarea 5C * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # Building 4019 * # I St. * # * # # * * # # * * # * # * # Building 4011 * # 4874 * # * # SRE Pond * # * # * # * # * # * # Former Building 4356 4015 Liquid and Gas Radioactive Storage Tanks Subarea 7 Northern Panhandle 17th Street Drainage 4015 * # * # # * Building 4006 * # 4055 * # * # * # * # # * * # * # *# # *# * * # * # Subarea 5A * # * # 4482 4487 * # * # * # Fuel Element Storage Facility * # * # * # # * * # * # * # * # * # # # * * * # * * # # # * # * * # * # * # * * # # * # * # * 4363 # * # * # * # * # G St. * ## ** # # * *# 4875 # * * # * # * # * # * # * # * # * # * # 4483 # * * # # * * # * # * # * ## * ** # *# # * * # # # * * # * # * # * # * # 4484 4485 * # * # * # * # * # * # * # * # * # ** # * ## * * # # # * * # * * # * # ## * * # * # * # * # * * # # * # 4020 # * # * * # # * * # *# # *# * * # * # 4020 * # * * # * # # * # *# * * # *# # * * # * # # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # 4462 4462 4487 * # * # * # * # Engineering Test Building Former Building 4003 * # 4461 * # 4009 * # * # * # * # * # * # * # * # * # * # * # S t. * # 4383 4009 * # * # * # 4483 * # * # * # 4486 4100 * # * * # # * # New Conservation Yard Drainage * # * # . 22nd St. * # Old Conservation Yard * # * # * # * # 4011 * # * # * # * # 4463 24th St. * # 4066 4462 4100 4100 * # * # * # 4486 4463 * # * # * # 4065 St * # * # * # * # 4066 F St. * # *# # *# * 4609 * # 4065 h 4011 24th St. * # * # * # t 18 . * # * # * # St 4062 * # * # * # * # h * # * # # * * # * # * # * # * # * # # * * * # # 4038 4038 * # * # * # * # * # * # * # * # # * * # * # # * * # * # * # * # t 20 * # * # * # * # S t. * # # * * # 4038 * # * # * # *# # ** # ## * * * # * * # # * # * # * # * # * # * # 4626 * # * # * # * # * # * # * # * # * # * ## * # * * # * # * # * # # * * # * # * # * # * # * # * # . * # * # * # * # * # * # 4816 4057 4626 * # * # 12 th * # * # * # * # 4046 * # * * # * # # # 4064# * * # * * # * # * # * # # * # * 4064 * # # * * # * # * * # *# # *# * # * # *# # *# * * # * # Subarea 6 * # St * # * # * # * # 4057 * # * # * # 4042 4026 4039 * # * # * # 4035 * # * # * # * # 4040 * # * # # * * # * # * # # * * # * 4014 # S t. * # h * # * # * # * # ## * * * # 4826 * # * # * # E * # t 17 * # * # * # * # # * * # * # # * * # # * * ## * * # # * # * * # * # * * # # # * *# *# # *# * 4825 4093 4042 * ## * * *# # * 4005 ## * * # * # * # # * 4006 4026 4026 4356 4059 * # * 4023 # 17th St. 4005 4006 4356 4059 * # * # 4032 * # 4355 4362 * # 4025 * # * # * # * # 17th St. 4019 * # * # * # * # * # # * 4019 * # * # Empire State Atomic Development Associates (ESADA) * # 4023 4013 * # * # 4003 * # * # # * * # G 4032 4013 # * 4693 4003 * # * # F St. # * * * # # 4027 4228 * # * 4003 # * # ## * * 4010 * # * # * # * # * # # * * # 4037 * # * # * # 4037 * # * # * # 4641 4641 4036 * # * # * # * # 4083 4027 * # * # 4641 4625 # * * # # * # * * *# # *# * # 4073 ## * * * *# # # * * # * # * # * # * # 4024 * # 4163 4103 4025 * # * # * # # * * # * # * # * # 4724 * # * # 4022 4663 * # # ** # * # 11th St. * # * # * # * 4163 # # * * # * # 4021 4024 # * * # * *# # * # * # * # * # * # * # S t. Sodium Graphite Reactor/ Organic Moderated Reactor Building 4009 * # # # * * # # * * # *# # ## ** * * * *# 4654 # * # * *# # * * # * # * # # * # * # * # *# # * # * # # * # * # * # *# # * # * * * # * # *# * # * * *# # *# * # * # * # # # * * # * * * # # # ** * # ## * *# # * *# # * # * * * # *# # # * * # 4665 * * # # * *# * # *# # * # 4664 * # # * *# # * * # * # h 10t * # * # * # * # # # * * * * *# # * # * # # *# # * # * # *# * # *# * # * # * # * * # 4075 * # * # *# * # * # *# # # # * * * * # # *# # * # # * * 4614 4621 * # * * * # # # * * # * # * # * # * # * # * # # * * # * # * # 4028 * # * # * # # * * # * # * # * # * # * # * # * # * # # * SRE Dam * # * # * # * * # # SRE Dam * # * # * # * # * # * # * # * # * # * # * # * # 4723 * # # * * *# *# # * # # # * ** # * * # *# *# # *# # * * # * # * # * * # # * # * # * * # * # * * # *# # *# # * # # * # * **# # * # * # * # # * ** * # # * # * # *# * # * # # *# # * * # * # * # * *# * # # * *# # * # * # *# * * # # *# *# * # # *# * *# * * # # *# 4143 *# * # * # * *# # * # 4143 *# * 4143 *# # * # *# * # *# # * * # * # * # * # * # * * 4041 *# # * # * # * # * *# # *# # *# # * # * * # * # * # * 4133 *# # # * *# *# # * # #* * * # * # * # * # * # * # * *# # * # # * # # * * * * # * # *# * # # ** # * # # * # * * # # * # * # * # * # # * * # Northern Buffer Zone West Southern California Edison Substation * # * # * ## * * # * # * # * # * # * # See Inset SNAP Experimental Reactor Facility Former Building 4010 * # * # * # # * * # * # * # # * * # * # * # * # * * # # Shield Test Irradiation Reactor * # Subarea 3 * # * # * # * # * # * # Outfall #3 # * * # Notes: FAL - Field action level GEL - GEL Laboratories, Inc KEWB - Kinetics Experiment Water Boiler NBZ - Northern Buffer Zone SNAP - Systems Nuclear Auxiliary Power TAL - Test America Laboratories RMHF - Radioactive Materials Handling Facility pCi/g - picocuries per gram 0 250 ³ 500 Feet U.S. EPA Region 9 1000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\FAL_Plates\ Fig4-9_Eu-152_Surface.mxd 12/19/2012 pbillock Boeing 2011, HGL 2012 Northern Buffer Zone East * # * # * # * # Sodium Reactor Experiment (SRE) Complex * # * # * # St. 3r d Radioactive Materials Handling Facility (RMHF) Complex * # * # * # * # # * * # * # * # * # Subarea 7 * # * # Outfall #3 * # * # * # * # * # * # * * # # * # * # * # * # * # ** # ## * * * # ## *# * * *# # * # * *# # # * * # * # *# # * # * # ** # * # * # * # * ## ** # * # * # * # * # * # 4056 Landfill * # * # * # * # * # * # * # * # 4010 * # * # * # 4013 * # * # * # 4024 4036 4027 4037 # * * 4032# # * 4032 4025 4006 4355 4059 * # * # * # * # * # 12 th * # * # * # # * * # * 4014 # * # # * * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # # * * # * # * # * # * # # * * # * *# # * # * # * # * # # # * * * # * # S t. * # * # * # * # * # Subarea 5A h St . Building 4029 * # * # * # h St t 18 . * # 4065 4066 4065 4066 4100 # * # * * # * # 4100 4100 * # s F ir e Rd. * # * # * # * # * # * # * # * # # * * * # ## * * *# # * # * # H St * # * # * # * # * # 4814 * # * # # * * # * # 4314 * # * # * # * # * # * # # # * * * # *# # *# * * # 4318 * # * * # # * # * # * # * # * 4425 # # * * # * # * * # # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * *# # *# * * # * # * # * # * # * # * # * # * # * # # * # * * # # * * # 4055 4383 Inset # * * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # Hazardous Waste Management Facility Building 4133 Radioactive Materials Handling Facility Complex Plutonium Development Facility Building 4055 * # * # * # Former Buildings 4375 and 4875 * # Pond Dredge Area * # Former Buildings 4173/4865 * # * # * # # * * # * # * # Subarea 5D South * # # * * * # # # * ** * # # # * # * # * # * # * # * # * * # # * # * # * # * # * # * # * # * # * * # # Shield Test Irradiation Reactor ## * * * # * # * # 4621 * # * # * # * # * # * # * # * # GEL (FAL = 0.670) Below FAL * # TAL (FAL = 0.0459) (Below 0.670 pCi/g) (Below 0.0459 pCi/g) FAL to less than 2 times FAL # * (0.0670 to 0.133 pCi/g) (0.0459 to 0.0917 pCi/g) 2 times to less than 3 times FAL # * (0.134 to 0.200 pCi/g) (0.0918 to 0.137 pCi/g) 3 times to less than 4 times FAL # * (0.201 to 0.267 pCi/g) (0.138 to 0.183 pCi/g) Greater than 4 times FAL # * (0.268 to x.xxx pCi/g) (0.184 to x.xxx pCi/g) Subareas Likely Remediation Zones Chemical (as of 5/2012) Structures Existing Removed There were no samples which corresponded to the boxed symbol. # * * # * # * # * # * # * # * # * # * # * * # # * # 4103 * # * # * # 4083 4663 * # * *# # * # * # * # * # * # * # 4046 * # * # * # * # 4036 4625 4037 * # 4064 * # 4641 * # * # * # * # * # * # * # * # * # * # * # 4014 4035 L85 Nuclear Experimentation Reactor Building 4093 * # 4021 * # * # * # # * * # * # t. ES * # * # * # 4825 * # Kinetics Experiment Water Boiler Former Building 4073 * # * # * # * # * # * # GS 4027 4024 * # * # * # * # t. 11th St. * # * # * # HGL—Radiological Characterization of Soils in Area IV and NBZ, Santa Susana Field Laboratory—Ventura County, California Figure 4.10 Europium-152 Round 1 and 2 Subsurface Soil and Sediment Results Santa Susana Field Laboratory Area IV and NBZ Radiological Study Roads Approximate Drainage Pathways 20-foot elevation contours * # 4693 * # * # 4025 Europium-152 * # # * # # * # * * 4665 4010 Legend * # * # Interim Storage Facility Building 4654 * # * # * # * # * # Engineering Test Building * # Former Building 4003 * # * # 4003 Sodium Reactor Experiment Complex # * * # * # * # * # * # * # # * * # * # * # # * * * ## * # # * * # *# # *# * * # * # # * * # * # * # * # * ## * * # * # * # # * * # # * * # 4664 4075 * # * # * # * # * # * # * # * # St. * # *# # * 4163 * # * # * # * # Hot Oil Sodium Cleaning Facility * # * # 10th * # * *# # * # * # * # 4022 * # * # # * * # * # * # * # * # * # * # * # * # * # # * # * * # * ## * * * # # *# * # # * * * # * # # * * # # * # * # # * * # * # # * * # * # # * * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # # # * * * # * # * # * # * # * # * # * # * * * # *# ## * # # * * # * # * # * # * # * # * # * # * # * # * # 4724 * # * # # * * # * # * # * # * # * # * # * # * # * # * # * # * # * * # # * # * # * # * # * # * # * # * # * # # * * * # # * # * # * # * # * # * # * # * *# # * # * # * # * # * # * # * # * # # # * * * # 4723 * # 4143 * # # * * # * # * # * # * # * # RMHF Leachfield * # * # SRE Dam * # * # *# # * * # * # Site 4614 RMHF Holdup Pond/Catchment * # Basin * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * ## * * * # # * # * # * # * # * # Hot Lab - Former Building 4020 * # * # * # * # Outfall #3 Former Building 4353 * # # * * # # * * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # 4373 Leach Field * # * # * # * # * # * # * # * # * # Subarea 5D North * # * # * # * # * # * # * # * # * # * # * # Fast Critical Experiment Building 4100 * # * # * # Subarea 8 South * # Building 4015 # * * # # * 4353 * # # * * # * # * # * # * # * # # * * # # * * # Subarea 5C 4353 I St. * # * # * # * # * # * # * # * # * # * # SRE Pond * # Building 4019 * # * # * # Building 4011 * # Liquid and Gas Radioactive Storage Tanks * # Former Building 4356 * # 4874 Subarea 7 Northern Panhandle 17th Street Drainage 4015 * # * # # * Building 4006 * # * # * # Subarea 5B 4015 * # 4374 * # * # 4848 * # * * # # * # * 4373 # * * * # # * # # * # * # * # * # * # * # J St. 4055 * # * # * # *# # *# * * # * # Former Building 4005 Heavy Metal Likely Remediation Zone * # * # * # # * * # * # * # * # * # * # Former Building 4023 * # * # * # * # # * * # * # * # * # * # * # # * * * # # * * # # * * # * # # * # * # * # # * * # * # # * * # * 4363 # * # * # * # * * * # ## ** # # *# 4875 # * * # * # * # * # * # * # * # * # * # * # * # G St. * # * # * # * # * # # * * *# # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # ** # * ## * * # # # * * # * * # * # ## * * # * # * # * # * * # # * # 4020 # * # * * # # * * # *# # *# * * # * # 4020 * # * *# # * * # # * # *# * * # *# # * * # * # # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # # * * # 4482 4487 4487 * # * # * # * # 4383 4009 * # * # * # * # 22nd St. * # * # Arnes * # 4461 4100 * # 4009 * # Kinetics Experiment Water Boiler - Former Building 4073 * # * # 4483 * # * # * # 4484 4485 * # * * # # * # * # * # * # 4483 4462 4462 24th St. * # 4486 4462 4463 24th St. # * *# # * * # # * * # * # * # * # . 4486 4463 * # * # St 4011 * # * # * # h * # F St. * # Fuel Element Storage Facility * # t 20 4062 4609 4885 * # Engineering Test Building Former Building 4003 L85 Nuclear Experimentation Reactor - Building 4093 * # * # * # * # New Conservation Yard Drainage * # * # * # 4011 * # * # * # Old Conservation Yard * # * # 4038 4038 * # * # * # * # t 17 4626 * # * # * # * # * # 4042 * # * # * # * # # * * # * # * # * # * # * # * # 4038 * # * # * # * # * # * * # # * # * # * # * # Subarea 6 * # * # # * * # * # 4626 * # * # * # * # * # * # # * 4057 4626 * # * # * # * # * # * # 4040 * # * # * # * * # * # # # 4064# * * # * * # * # * # * # # * # * 4064 * # * # * # * # S t. * # F St. S t. * # 4057 * # * # * # * # * # # * * # * # # * * # * # ## ** # *# * G 4816 * # * # * # * # * # * # * # 4826 4039 * # * # * # # * * # 4042 4026 4356 * # * # * # * # * 4005 ## * * * # # * # * # # * 4006 4026 4026 4356 * # * # * # 11th St. 17th St. * # * # * # * # * # * # * # * # * # * # 4641 # * # * *4023# # * # * # * *# # * * 4023 # * # * # 4005 * # * *# # 4059 * # # * * # # * 4037 * # * # * # * # * # * *# # # * * # * # # * * # 4027 4019 4362 4693 4641 4641 * # * # * # * * # # * # * # * # # * 4046 4093 * # * # * # * # * # * # * # 4083 * # * # E * # # * * ## * 4073 * # # * 17th St. 4019 * # 4103 * # * # * # * # * # 4625 * # * # * # * # * # 4035 4021 4663 * # * # Southern California Edison Substation * # * # * # * # * # 4022 4024 4724 * # * # * # # * * *# # *# * # 4825 * # 4013 * # # * # * * # * # # * * # * # * # * # # ** # * # # * * # * * # * # # * # * # *# # * # *# * # * * # *# * *# # * * # * # # * * # * # # * # **# # * # * # # * * # 4163 * # * # # * *# * # * # # *# * * # * # * # * # * # * 4163 *# # * 4143 # *# * * # # *# * * # *# *# # * # * # # * *# # * # * * * # * # * *# * # *# * # # * ## * *# # 4143 *# * *# # * 4143 * # *# # *# * # # * *# * # # * # 4003 *# # * * * # * # * # * # * * # * # * # # * # # * # * * # 4041 * # * # * 4003 *# # * # * # * # * * # * # # *# # *# * * 4133 *# # * # * # * # # * * # 4003 * # * # * # * # 4665 4664 * # 4228 * # * # * # * # 4025 * # * # * # * # * # * # Empire State Atomic Development Associates (ESADA) * # * # * # ## * * * # Former Sodium Disposal Facility * # * # # ## ** 4654 # * # # * * *# * # * * # ** # * # *# # # * * *# # *# # * # * * * # # * # *# # * * # * # * # S t. * # * # * # * # * # SRE Dam # * * # * # # # * * SRE Dam # * * # * # * # * # * # * # * # * # 4723 * # # * * * # # * # # * * * # * # # *# * # * # # * * # # * h 10t * # * # * # * # # * # * ** # * # * # * # # * # *# # * # * * # 4075 # * * # *# *# * # * # # *# * * * # # # # * *# *# # * * # * 4614 4621 * # * # # * * # * # * *# # * # * # * # * # * # * # *# # * # * # * *# # *# ** # * # * # * # * # *# # * * 4028 # * # * # * # * # Building 4009 Leachfield * # # * * # * # * # * # Subarea 3 * # * # * # * # * # * # * # Northern Buffer Zone West * ## * * # * # * # * # # * * # SNAP Experimental Reactor Facility Former Building 4010 * # * # * # * ## * * # * # * # # * # # * * * # # # * * * # # * * # *# * # * # * # # * * # * # # * * # Subarea 8 North * # * # # * See Inset Shield Test Irradiation Reactor Sodium Graphite Reactor/ Organic Moderated Reactor Building 4009 * # * # * # # * * ## * * # * # * * # # * # * # * # * # # * * # * # Notes: FAL - Field action level GEL - GEL Laboratories, Inc KEWB - Kinetics Experiment Water Boiler NBZ - Northern Buffer Zone SNAP - Systems Nuclear Auxiliary Power TAL - Test America Laboratories RMHF - Radioactive Materials Handling Facility pCi/g - picocuries per gram 0 250 ³ 500 Feet U.S. EPA Region 9 1000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\FAL_Plates\ Fig4-10_Eu-152_Subsurface.mxd 12/19/2012 pbillock Boeing 2011, HGL 2012 * # * # DRAFT * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # Northern Buffer Zone East * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # Sodium Reactor Experiment (SRE) Complex * # * # * # St. 3r d * # Radioactive Materials Handling Facility (RMHF) Complex * # * # * # * # * # * # # * * # * # * # Subarea 7 * # * # * # * # * # * # * # * # # * * * # # * # * # * # # * * # * # * # * # * # * # 4056 Landfill * # * # * # Building 4009 Leachfield * # * # * # * # * # * # * # 4013 * # * # 4059 4059 * # * # * # 4100 * # * # * # Arnes * # s F ir e Rd. * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # 4814 # * * # * # * # * # * # * # * # 4314 * # * # * # * # * # * # H St * # * # * # * # * # # # * * * # * # *# # *# * * # * # 4318 # * * # # * * * # * # # * # 4425 * # * # * # * # * # * # * # * # * # * # * # * # # * * # # * * # * # * # * # * # * # * # * # St . Kinetics Experiment Water Boiler - Former Building 4073 * # Former Building 4023 * # Former Building 4005 * # * # Heavy Metal Likely Remediation Zone 4383 Inset Subarea 5B * # * # * # 4353 I St. * # * * # # * # * # * # # * * # # * * # * 4353 # * # * # # * * # * # * # * # * # * # * # * # * # * # * # * # * # * # Radioactive Materials Handling Facility Complex * # * # Outfall #3 Former Building 4353 * # Pond Dredge Area Former Buildings 4173/4865 * # Site 4614 RMHF Holdup Pond/Catchment * # Basin * # * *# # * # * # Subarea 5D South * # * # * # * # * *# # * # * # * # 4621 * # * # * # * * # # 4103 4083 * # * # * # * # * # * # # * * # * *# # * # # * (Below 0.0480 pCi/g) (Below 0.00921 pCi/g) FAL to less than 2 times FAL # * (0.0480 to 0.0959 pCi/g) (0.00921 to 0.0183 pCi/g) 2 times to less than 3 times FAL # * (0.0960 to 0.143 pCi/g) (0.0184 to 0.0275 pCi/g) Below FAL * # 3 times to less than 4 times FAL # * (0.144 to 0.191 pCi/g) (0.0276 to 0.0367 pCi/g) Greater than 4 times FAL # * (0.192 to x.xxx pCi/g) (0.0.368 to x.xxx pCi/g) Likely Remediation Zones Chemical (as of 5/2012) Structures Existing Removed There were no samples which corresponded to the boxed symbol. * * # # 4825 * # # * * # * # * # t. ES * # 4014 * # * # L85 Nuclear Experimentation Reactor Building 4093 * # 4035 * # * # * # 4046 * # * # * # 4064 * # 4641 * # Shield Test Irradiation Reactor Kinetics Experiment #* * # Water Boiler * # Former Building 4073 4036 4625 * # 4037 * # * # * # * # * # * * # # GS t. 11th St. * # * # HGL—Radiological Characterization of Soils in Area IV and NBZ, Santa Susana Field Laboratory—Ventura County, California Figure 4.11 Plutonium-238 Round 1 and 2 Surface Soil and Sediment Results Santa Susana Field Laboratory Area IV and NBZ Radiological Study Roads Approximate Drainage Pathways 20-foot elevation contours * # 4027 4024 Subareas * # * # * # Legend TAL (FAL = 0.00921) * # * # 4025 GEL (FAL = 0.0480) * # * # * # * # # * 4010 Plutonium-238 * # * # * # * # 4663 * # * # * # * # 4021 * # * # * # * # * # 4664 4075 * # Sodium Reactor Experiment Complex * # * # St. * # * # * # * # Interim Storage Facility Building 4654 * # * # * # * # * # * # 10th * # * # * # * # # * *# *# # * * # * # # * * # * # * # 4022 * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # 4665 * # 4693 * # * # # * * # * # * # # * * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * ## * * # * # * # 4003 * # * # * # * # Engineering Test Building * # Former Building 4003 4143 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # *# # * * # * # * # * # 4724 * # * # * # # # * * *# # * *# # * * # * # * # * # * # * # * # RMHF Leachfield Hot Oil Sodium Cleaning Facility * # * # 4163 * # * # * # * # * # * # * # * # * # * # * # * # * # ** # # * # * # Former Buildings 4375 and 4875 * # * # 4723 * # * # # * * # * # Hot Lab - Former Building 4020 * # * # * # # * * * # *# # # * * # * # * * # # # * # * * * # # * # # * # * # * * # * # * *# # * # * # * # * # * # * # # * * # SRE Dam * # * # * # * # * # * # * # * # * # * # * # * # * # Plutonium Development Facility Building 4055 * # Subarea 8 South * # * # * # * # * # * # * # Hazardous Waste Management Facility Building 4133 * # 4373 Leach Field * # * # * # * # * # * # * # * # Subarea 5D North * # * # * # * # * # * # * # * # * # * # Fast Critical Experiment Building 4100 * # * # * # * # Building 4015 * # * # * # Subarea 5C * # * # # * * # * # * # * # * # # # * * * # * * # # # * # * * # * # * # * * # # * # * # * 4363 # # * * # * # Building 4019 * # 4874 * # * # * # * # * # * # * # * # * # Building 4011 *# ## * * * # SRE Pond * # Former Building 4356 4015 * # Liquid and Gas Radioactive Storage Tanks Subarea 7 Northern Panhandle 17th Street Drainage 4015 4374 * # 4848 * * # * # # * # * 4373 # * * # # * # * # * # * # # * # * * # J St. 4055 * # Building 4006 * # 4055 * # * # h * # # * * # * # * # * # * # * # * # * # # * * # * # * * # # * # * # * # L85 Nuclear Experimentation Reactor - Building 4093 * # G St. * # # # # * *# * # ** * # 4875 * # * # * # * # * # * # * # * # * # * # * # Building 4029 * # * # 4482 4487 * # * # * # * # # * * # 4483 * # * # * # * # * # * # * # * # * # * # * # # * # * * # * * # * # *# # * # * # * # * * # # * # 4020 # * # * * # # * * # *# # *# * * # * # 4020 * # * * # * # # * # *# * * # *# # * * # * # # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # Subarea 5A * # 4484 4485 4487 * # * # * # * # * # * # * # 4461 * # 4009 * # * # * # * # * # * # * # * # * # * # * # * # 4383 4009 * # Fuel Element Storage Facility * # * # 4483 * # * # * # 4486 4100 * # * * # # * # * # * # * # 4011 * # * # * # * # * # * * # # 22nd St. * # * # * # Engineering Test Building Former Building 4003 * # * # 4462 24th St. * # 4066 4462 4100 4100 * # * # * # 4065 4462 4463 24th St. * # * # * # * # 4486 * # * # * # 4066 F St. 4463 4885 S t. 4011 * # * # t 18 . * # * # 4065 * # * # * # St 4062 4609 * # * # * ## * * # * # # * * * # # 4038 4038 * # * # * # * # . 4626 * # * # * # S t. * # * # h * # * # # * New Conservation Yard Drainage * # * # * # # * * # * # * # * # 12 th * # 17th St. 4816 4038 * # * # * # * # 4626 * # * # * # t 20 * # * # Old Conservation Yard * # 4042 4026 4057 4626 * # * # * # * 4023 # * # * # * # * # 4042 * ## * * *# # 4005 4057 * # * # * # * # # * # * * 4064# # * # * * # * # * # # * # * 4064 * # # * * # * # * * # *# # G 4005 * # * # * # * # * # St * # * # * # * # * # ## * * 4037 * * # # * # * # 4035 4046 4093 * # * # # * * # h * # * # * # * # 4006 4039 * # * # 4040 * # 4826 * # * # * # # * * # Subarea 6 * # * # * 4014 # t 17 * # * # * # * # * # * # t. * # * # * # * # 4037 4032 4026 4026 4356 * # * # 4036 4027 * # 4023 4006 4356 * # ES 4641 4641 * # 4355 4362 * # * # 4825 4027 * # * # * # 4625 4024 17th St. 4019 * # * # # * ## * * * # * # # * * # # * * ## * * # # * # * * # * # * * # # # * *# *# # *# * * # # * * # * # * # 4641 4019 * # * # * # * # * # 4083 4013 * # * # * # * # 4073 4025 * # * # * # * # * # 4003 * # * * # # ## * * 4032 * # * # 4003 * # * # * # 4025 * # * # * # F St. # * 4693 * # 4103 4228 * # * # * # * # 4663 * # # ** # * # * # * # * # 4021 * # 4143 4041 * # 4022 * # * # * # 4010 * # * # Empire State Atomic Development Associates (ESADA) 4665 * # * # * # 11th St. * *# # * # * # Former Sodium Disposal Facility * # 4654 # * * # * # *# # * # * * # * * # * ## 4664 4024 * # * # * ## * * ## * * ## * * # * # * # # * * *# # * # # * * # # * # * * # * # * # 4163 S t. Sodium Graphite Reactor/ Organic Moderated Reactor Building 4009 *# # # * * *# * # * # # * *# # * h 10t * # * # * # 4724 * # * # ## * * *# * # * # * # # * * *# # * # # * # *# * # * # * # * # * * # 4075 # * * # *# # * # * # *# # * * * # *# # * 4614 4621 * * # # # * * # * # * # * # * # # * * # * # * # * # 4028 * # * # * # # * * # * # * 4163 # * 4003 # * # * # * # * # # 4133 ** # # * * # * # * # * # * # 4143 * # * # ## * * * # * # * # * # * # * # * * # # * # # # # * * * SRE Dam * # * # * # # # * * SRE Dam # * * # * # * # * # * # * # * # * # 4723 * # * # * # # * * * # * * # *# # *# # * # # # * * **# * # *# # * # # * ** * # # * # # # * *# * # *# # * * # * # * *# # * # * *# # *# # * 4143 # * * # * # * # * # ## * * * * # ## * * # * # * # * # * # * # * # * # * # * # Southern California Edison Substation * # * # * # * # * # * # * # See Inset Northern Buffer Zone West * # * # * # * # SNAP Experimental Reactor Facility Former Building 4010 * # # * * # * # # * Shield Test Irradiation Reactor * # * # * # * * # # Subarea 8 North * # Subarea 3 * # * # * # * # * # * # Outfall #3 # * * # Notes: FAL - Field action level GEL - GEL Laboratories, Inc KEWB - Kinetics Experiment Water Boiler NBZ - Northern Buffer Zone SNAP - Systems Nuclear Auxiliary Power TAL - Test America Laboratories RMHF - Radioactive Materials Handling Facility pCi/g - picocuries per gram 0 250 ³ 500 Feet U.S. EPA Region 9 1000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\FAL_Plates\ Fig4-11_Pu-238_Surface.mxd 12/19/2012 pbillock Boeing 2011, HGL 2012 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # Northern Buffer Zone East * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # Sodium Reactor Experiment (SRE) Complex * # * # * # St. 3r d * # Radioactive Materials Handling Facility (RMHF) Complex * # * # * # * # * # * # # * * # * # * # Subarea 7 * # * # * # * # * # * # * # * # # * * * # # * # * # * # # * * # * # * # * # * # * # 4056 Landfill * # * # # * *# # *# * # * # * # * * # # * *# # * # * # *# *# * * # * # ** # 4614 * # # * # # * * # * # * # * # * # * # Building 4009 Leachfield * # * # * # * # * # * # * # * # * # 4059 * # 4059 4626 4062 * # * # * # * # * # * # * # 4100 * # Arnes s F ir e * # * # * # # * * # # * Rd. * # * # * # * # * # * # * # * # * # * # * # # * * # * # # * * # * # * # * # * # * # * # 4314 * # * # * # * # * # 4814 * # * # * # * # H St * # * # * # # # * * * # * # *# # *# * * # * # 4318 # * * # # * * * # * # # * # 4425 * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * * # # * # * # * # # * * # # * * # * # * # * # * # * # Subarea 5A * # * # Building 4029 * # * # * # L85 Nuclear Experimentation Reactor - Building 4093 * # h St . Kinetics Experiment Water Boiler - Former Building 4073 * # Former Building 4023 * # Former Building 4005 * # * # Heavy Metal Likely Remediation Zone 4383 Inset Subarea 5B G St. * # 4374 * # 4848 * * # * # # * # * 4373 # * * # # * # * # * # * # # * # * * # J St. 4055 * # * # 4015 * # # * * # # * * # * 4353 # * # * # # * * # I St. * # * # * # * # * # * # * # * # * # * # * # Subarea 8 South * # * # * # ## * * *# * # Radioactive Materials Handling Facility Complex Plutonium Development Facility Building 4055 * # * # * # * # Outfall #3 Former Building 4353 * # Pond Dredge Area Former Buildings 4173/4865 * # Site 4614 RMHF Holdup Pond/Catchment * # Basin * # Subarea 5D South * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # 4621 * # * # * * # # 4103 4083 * # 4663 * # * # * # * # * # * # # * * # * *# # * # # * Below FAL * # (Below 0.0410 pCi/g) (Below 0.0162 pCi/g) FAL to less than 2 times FAL # * (0.0410 to 0.0819 pCi/g) (0.0162 to 0.0323 pCi/g) 2 times to less than 3 times FAL # * (0.0820 to 0.122 pCi/g) (0.0324 to 0.0485 pCi/g) 3 times to less than 4 times FAL # * (0.123 to 0.163 pCi/g) (0.0486 to 0.0647 pCi/g) Greater than 4 times FAL # * (0.163 to x.xxx pCi/g) (0.0648 to x.xxxx pCi/g) Likely Remediation Zones Chemical (as of 5/2012) Structures Existing Removed There were no samples which corresponded to the boxed symbol. * # * # * * # # * # 4825 * # # * * # * # * # t. ES * # 4014 * # * # L85 Nuclear Experimentation Reactor Building 4093 * # 4035 * # * # * # 4046 * # * # * # 4064 * # 4641 * # Shield Test Irradiation Reactor Kinetics Experiment #* * # Water Boiler * # Former Building 4073 4036 4625 * # 4037 * # * # * # * # * # * * # # GS t. 11th St. * # * # HGL—Radiological Characterization of Soils in Area IV and NBZ, Santa Susana Field Laboratory—Ventura County, California Figure 4.12 Americium-241 Round 1 and 2 Surface Soil and Sediment Results Santa Susana Field Laboratory Area IV and NBZ Radiological Study Roads Approximate Drainage Pathways 20-foot elevation contours * # 4027 4024 Subareas * # * # Legend TAL (FAL = 0.0162) * # * # * # * # * # 4025 GEL (FAL = 0.0410) * # * # # * 4010 Americium-241 * # * # * # 4021 * # * # * # * # * # 4664 4075 * # Sodium Reactor Experiment Complex * # * # * # * # * # * # 4665 * # Interim Storage Facility Building 4654 4022 * # # * * # * # * # * # St. * # * # * # * # * # * # # * * # # * * # * # * # * # * # * # * # * *# # * # * # 4693 * # * # # * * # * # * # 10th * # * # * # * # * # * ## * * # * # * # * # * *# # * # * # * # * # * # * # * # * # * # Engineering Test Building * # Former Building 4003 4003 * # * # * # * # * # 4143 * # * # * # * # * # * # * # * # * # * # * # * # * # 4724 * # * # *# # * * # * # * # * # * # * # * # # # * * *# * # * # RMHF Leachfield Hot Oil Sodium Cleaning Facility * # * # 4163 * # * # # * *# # * * # * # * # * # * # * # * # * # * # * # ** # # * # * # * # * # 4723 * # * # # * * # * # * # * # * # * # * # # * * # * # Former Buildings 4375 and 4875 * # * # * # * # * # Hot Lab - Former Building 4020 * # * # * # # * * * # *# # # * * # * # * * # # # * # * * * # # * # # * # * # * * # * # * *# # * # * # SRE Dam * # * # * # * # * # * # * # 4373 Leach Field * # * # * # * # * # * # Hazardous Waste Management Facility Building 4133 * # * # * # * # * # * # * # * # * # * # * # * # Subarea 5D North * # * # * # * # * # * # * # * # * # * # Fast Critical Experiment Building 4100 * # * # * # * # * # * # * # Building 4015 4353 * # * # Subarea 5C * # * # # * * # * # * # * # * # * # # # * * * # * * # # # * # * * # * # * # * * # # * # * # * 4363 # # * * # * # * # * # * # Building 4019 * # 4874 * ## ** # *# * # * # * # * # * # * # Building 4011 * # SRE Pond * # Former Building 4356 4015 * # Liquid and Gas Radioactive Storage Tanks Subarea 7 Northern Panhandle Building 4006 * # 4055 * # 17th Street Drainage * # * # * # Fuel Element Storage Facility * # * # 4482 4487 # * * # * # * # * # * # * # 4483 * # * # * # * # * # 4484 4485 * # # * 4875 * # * # * # Engineering Test Building Former Building 4003 * # * # * # * # * # * # * # * # * # 4462 * # * # * # S t. * # 4483 * # * # * # * # * # * # * # * # * # * # * # # * # * * # * * # * # *# # * # * # * # * * # # * # 4020 # * # * * # # * * # *# # *# * * # * # 4020 * # * * # * # # * # *# * * # *# # * * # * # # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * * # # 4486 4462 * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # 4011 4487 * # * # * # * # * ## * 4461 * # 4009 * # * # * # * # * # * # * # * # * # * # * # S t. * # 4383 4009 * # * # * # * # * # * # * # 4066 4100 * # * * # # * # New Conservation Yard Drainage * # * # 22nd St. * # * # * # 4463 24th St. * # 4065 * # * # * # 4066 4462 4100 4100 * # * # * # Old Conservation Yard * # * # 4486 * # * # 4065 F St. 24th St. * # * # * # * # # * # * * 4064# # * # * * # * # * # # * # * 4064 * # # * * # * # * * # *# # 4011 4463 4885 * # * # * # * # t 18 . * # St * # 12 th * # 17th St. # * * * # # * # * # * # 4005 4038 4038 * # 4609 * # * # # * * # * # * # * # * # * # * # * # * # # * * * # # * # # * * # 4006 h * # * # * # * 4023 # 4816 * # * # * # * # 4042 4005 4038 * # * # * # * # * # 4035 * # ## * * 4042 * ## * * *# # 4626 * # * # Subarea 6 * # * # t 20 * # * # * # 4046 4093 4037 4032 4057 4626 * # * # * # # * * # * # * # * # * # G * # * # * # * # 4040 * # . * # * # * # * # * 4014 # St * # * # * # t. 4027 4057 * # * # ES * # 4037 4026 4039 * # * # 4825 * # * # * # h * # * # * # 4826 * # * # * # 4036 * # 4023 4026 4026 4356 * # * # # * * ## * * # # * # * * # * # * * # # # * *# *# # *# * 4641 4641 4027 ## * * * # * # # * * # t 17 * # 4625 4024 4006 4356 * # * # # * * # 4355 4362 * # * # * # 4083 4028 * # * # * # * # 17th St. 4019 * # * # # * * # * # * # 4641 4019 * # * # * # * # 4003 * # 4073 4013 * # * # 4003 * # * # * # * * # # ## * * 4032 4013 * # * # * # # * 4693 * # * # 4663 * # # ** # 4025 * # * # * # * # 4621 * # * # F St. * # 4025 * # * # * # 4103 4228 * # Empire State Atomic Development Associates (ESADA) * # * # * # 4010 * # * # Former Sodium Disposal Facility * # * # * # * # * # * # 4021 * # 4143 4041 * # 4022 4075 * # * # * # 11th St. * *# # * # * # 4665 4654 # * * # * # *# # * # * * # * * # * ## 4664 4024 * # * # * # * # * # 4163 S t. Sodium Graphite Reactor/ Organic Moderated Reactor Building 4009 * ## * * ## * * ## * * # * # # * * # # * # * * # * # * # # * *# # * h 10t * # * # *# # # * * *# * # # * * # * # * # * # 4724 * # * # ## * * *# * # * # * # # * * *# # * # # * * # * # * 4163 # * 4003 # * # * # * # * # # 4133 ** # # * * # * # * # * # * # 4143 * # * # ## * * * # * # * # * # * # * # * * # # * # # # # * * * SRE Dam * # * # * # # # * * SRE Dam # * * # * # * # * # * # * # * # * # 4723 * # * # * # # * * * # * * # *# # *# # * # # # * * **# * # *# # * # # * ** * # # * # # # * *# * # *# # * * # * # * *# # * *# # *# # * 4143 # * * # * # * # * # ## * * * * # ## * * # * # * # * # * # * # * # * # * # * # Southern California Edison Substation * # * # * # * # * # * # * # See Inset Northern Buffer Zone West * # * # * # * # SNAP Experimental Reactor Facility Former Building 4010 * # # * * # * # # * Shield Test Irradiation Reactor * # * # * # * * # # Subarea 8 North * # Subarea 3 * # * # * # * # * # * # Outfall #3 # * * # Notes: FAL - Field action level GEL - GEL Laboratories, Inc KEWB - Kinetics Experiment Water Boiler NBZ - Northern Buffer Zone SNAP - Systems Nuclear Auxiliary Power TAL - Test America Laboratories RMHF - Radioactive Materials Handling Facility pCi/g - picocuries per gram 0 250 ³ 500 Feet U.S. EPA Region 9 1000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\FAL_Plates\ Fig4-12_Am-241_Surface.mxd 12/19/2012 pbillock Boeing 2011, HGL 2012 Northern Buffer Zone East * # * # * # * # Sodium Reactor Experiment (SRE) Complex * # * # * # * # St. 3r d Radioactive Materials Handling Facility (RMHF) Complex * # * # * # * # # * * # * # * # * # Subarea 7 * # * # * # Outfall #3 * # * # # * * * # # Northern Buffer Zone West * # * # # ** # * # * # * # * # # * * # * # # ** # # # * * * # * # * # * # * # Subarea 8 North * # * # * # *# # * *# * # * # # * * # * # * # * # * # * # * # * # * # * # * # 4010 * # * # * # * # * # * # * # * # * # * # * # * # * # * # 4013 * # * # * # * # * # 4059 * # * # * # * # * # F St. * # 4693 * # * # # * * # * # E 4083 4040 * # * # # * 4046 4093 * # 4641 4641 4036 4027 # * * # # * 4037 * # # 4064# * * * * # # * # * # # * # * 4064 * # Old Conservation Yard 4037 * # * 4032# # * 4032 * # * # * # G # * # * *4023# # * # * # * *# # * * 4023 # * # * # S t. Engineering Test Building Former Building 4003 11th St. 12 th 17th St. S t. * # * # 4042 4042 * # * # * # * # * # Subarea 5A h * # St . Building 4029 * # * # 4038 4038 L85 Nuclear Experimentation Reactor - Building 4093 * # h St 4062 t 18 . * # 4065 4066 4065 4066 * # * # * # 4100 # * # * * # * # * # * # s F ir e * # * # # * * # # * * * # # * # * # * # 4100 4100 Rd. * # * # * # * # 4009 * # * # * # # * * # * # * # * # H St * # * # * # # * * # * # 4814 * # * # # * * # * # * # 4314 * # * # * # * # * # * # * # * # # # * * * # *# # *# * * # 4318 * # * * # # * # * # * 4425 # # * * # * # * * # # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # # * * # * # * # * # * # 4055 * # * # # * * # 4015 * # * # * # * # * # * # * # * # * # * # * # * # Subarea 8 South * # * # # * * # * # Radioactive Materials Handling Facility Complex Outfall #3 Pond Dredge Area * # Former Buildings 4173/4865 * # * # * # # * * # # * * * # # # * ** * # # # * # * # * # * # * # * # * # * # * # * # * # Shield Test Irradiation Reactor 4621 4103 4021 4083 4663 * # * *# # * # * # Below FAL * # TAL (FAL = 0.0162) (Below 0.0410 pCi/g) (Below 0.0162 pCi/g) FAL to less than 2 times FAL # * (0.0410 to 0.0819 pCi/g) (0.0162 to 0.0323 pCi/g) 2 times to less than 3 times FAL # * (0.0820 to 0.122 pCi/g) (0.0324 to 0.0485 pCi/g) 3 times to less than 4 times FAL # * (0.123 to 0.163 pCi/g) (0.0486 to 0.0647 pCi/g) Greater than 4 times FAL # * (0.163 to x.xxx pCi/g) (0.0648 to x.xxxx pCi/g) Subareas Likely Remediation Zones Chemical (as of 5/2012) Structures Existing Removed There were no samples which corresponded to the boxed symbol. * # * # 4014 * # * # * # * # 4046 * # * # * # 4064 * # * # * # 4641 * # # * * * ## * # # * * # *# # *# * * # * # # * * # * # * # * # * # 4036 4625 * # 4037 * # * # Kinetics Experiment Water Boiler Former Building 4073 * # * # * # GS 4027 4024 * # * # * # * # t. 11th St. * # * # HGL—Radiological Characterization of Soils in Area IV and NBZ, Santa Susana Field Laboratory—Ventura County, California Figure 4.13 Americium-241 Round 1 and 2 Subsurface Soil and Sediment Results Santa Susana Field Laboratory Area IV and NBZ Radiological Study Roads Approximate Drainage Pathways 20-foot elevation contours * * # # * # # * * # * # * # 4025 GEL (FAL = 0.0410) * # * # 4035 * # 4010 Americium-241 * # * # * # Legend * # t. ES L85 Nuclear Experimentation Reactor Building 4093 * # * # * # * # * # * # St. * # * # * # * # 10th * # * # # * * # * # * # 4664 4075 * # * # * # # * * # * # * # * # * # * # 4022 * # * # * # * # * # # * * # * # * # * # * # 4693 * # 4665 * # * # * # * # * # * # * # # * * # * # * # * # Subarea 5D South * # * # # * # # * # * * 4825 Interim Storage Facility Building 4654 * # # * * # * # * # * # Sodium Reactor Experiment Complex * # * # # * * # * # * # *# # * * # * # * # * # * # * # 4003 * # * # Engineering Test Building * # Former Building 4003 * # * # * # * # * # * # * # * # * # * # * # * # * # * # Hot Oil Sodium Cleaning Facility * # * # * # * # * # * # 4163 * # 4143 * # * # # * *# * # * # * # * # * # * # * ## * * * # # *# * # # * * * # * # # *# # * * # * # * # * # * # * # * # * # * # * # 4724 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # Site 4614 RMHF Holdup Pond/Catchment * # Basin * # * # # * * * # # * # * # * # * # * # Former Buildings 4375 and 4875 * # * # * # * # RMHF Leachfield * # * # * # * # * # * # * *# # * # * # * # * # * # Hot Lab - Former Building 4020 * # * # * # * # * # Former Building 4353 * # * # * # 4723 * # * # * # * # * # * # * # # * Hazardous Waste Management Facility Building 4133 Plutonium Development Facility Building 4055 * # * # # # * * * # * # # * * # * # 4373 Leach Field * # * # * # * # # * * # * # SRE Dam * # * # * # * # * # * # * # * # * # * # * # * # * # * # Subarea 5D North * # * # * # * # * # * # * # * # * # * # Fast Critical Experiment Building 4100 * # * # * # * # * # * # Building 4015 # * * # # * 4353 * # # * * # * # I St. * # * # # * * # Subarea 5C 4353 * # * # * # * # * # * # * # * # * # * # * # * # * # Building 4019 * # SRE Pond * # Building 4011 * # Liquid and Gas Radioactive Storage Tanks * # Former Building 4356 4015 * # 4874 Subarea 7 Northern Panhandle Building 4006 * # 4374 * # * # 4848 * # * * # # * # * 4373 # * * * # # * # # * # * # * # * # * # * # J St. 4055 * # 17th Street Drainage * # * # * # * # # * * # * # * # * # * # * # * # * # # * * # * # * # * # # * * # * # * # * # * # * # # * * * # # * * # # * * # * # # * # * # * # # * * # * # # * * # * 4363 # * # * # # * Subarea 5B G St. * * * # ## ** # # *# 4875 # * * # * # * # * # * # 4383 * # * # * # * # * # * # * # * # * # * # * # # * # * * # * * # * # *# # * # * # * # * * # # * # 4020 # * # * * # # * * # *# # *# * * # * # 4020 * # * * # * # # * # *# * * # *# # * * # * # # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # 4487 * # * # Inset 4461 * # * # * # * # 4482 4487 * # Heavy Metal Likely Remediation Zone 4483 4383 * # * # Former Building 4005 4484 4485 4100 * # 4009 * # * # 4462 * # * # # * Former Building 4023 * # * # 22nd St. Arnes Kinetics Experiment Water Boiler - Former Building 4073 4483 * # * * # # * # * # * # 4486 4462 24th St. * # * # . 4011 4462 4463 24th St. * # * # * # St 4486 4463 * # * # h * # F St. 4609 4885 * # Fuel Element Storage Facility * # t 17 4626 * # * # New Conservation Yard Drainage * # t 20 * # * # # * * # 4011 * # * # * * # # * # * # # * * # 4641 * # * # * # * # * # * # 4038 * # * # Subarea 6 * # * # * # # * * # * # * # * # # * * # * 4014 # * # * # * # * # * # * * # # * ## * 4626 * # * # * # * # S t. * # * # # * * # 4057 4626 * # * # * # 4005 4057 * # * # * # * # * # # * * # * # # * * # * # ## ** # *# * * # # * * # * # * # 4816 * # * # * # * # * # * # * # 4826 4039 * # * # * # * # * # 4825 4026 4356 * # * # * # 4006 4026 4026 4356 *# # * * # * # * # 4035 4073 4005 * # * *# # 4059 * # * # * # * # * # 4006 * # * # * # 4027 4024 * # # * *# # * * # 4724 4003 # * * # * # # * 4003 * # * # * # *# # *# * * # * # * # 4003 4654 * ## * *# # * * # * # * * # # * # 4625 * # 4163 * # * # * # 4024 * # * # * # * # 4663 * # * # # * SRE Dam # * * # 4723 * # * # * # * *# # * 4143 # * *# # # * * *# *# *# * # *# # * # * # 4143 # * # * * 4143 # * # # * # # * # * * * # * # * * # * # # 4041 * # * * # # 4103 * # 4355 * # * 4163 # * # * # * # * # * # SRE Dam # * * # * # # * * # * # # * * * # # * # * # *# # *# * *# #* ** # * * # # *# *# # * # * # * * # # * * # # 4022 4019 4362 * # * # * # * # * # 17th St. 4019 * # * # 4013 * # * # * # * # * # # * * # # * 4665 4025 * # * # * ## * * # * # 4021 * # 4228 * # # * * # * # *# # * 4664 * # 4025 * # * # * # * # * # S t. * # * # * # * # Southern California Edison Substation * # * # h 10t * # * # * # * # # * 4075 # * * # *# # *# * # *# * * * # # *# *# # * 4614 4621 * # # * * # * # * # * # * # * # * # * # *# # * # * # * *# # *# ** # * # * # * # * # *# # * * 4028 # * # * # * # * # * # # * * # * # * * # # * # * # * # # * * # *# # *# * * # * # * # * # * # * # # 4133 ** # # * * # * # * # * # * # * # * # # * * # * # * # * # * # # * * # * # * # * # * # * # * # # * * # * # * # * # * # Empire State Atomic Development Associates (ESADA) * # * # * # Subarea 3 * # * # * # Former Sodium Disposal Facility * # * # * # SNAP Experimental Reactor Facility Former Building 4010 Sodium Graphite Reactor/ Organic Moderated Reactor Building 4009 * # * # * # * # Building 4009 Leachfield * # * # * # # * See Inset Shield Test Irradiation Reactor 4056 Landfill * # * # * # # * * ## * * # * # * * # # * # * # * # * # # * * # * # Notes: FAL - Field action level GEL - GEL Laboratories, Inc KEWB - Kinetics Experiment Water Boiler NBZ - Northern Buffer Zone SNAP - Systems Nuclear Auxiliary Power TAL - Test America Laboratories RMHF - Radioactive Materials Handling Facility pCi/g - picocuries per gram 0 250 ³ 500 Feet U.S. EPA Region 9 1000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\FAL_Plates\ Fig4-13_Am-241_Subsurface.mxd 12/19/2012 pbillock Boeing 2011, HGL 2012 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # Northern Buffer Zone East * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # * # Sodium Reactor Experiment (SRE) Complex * # * # * # St. 3r d * # Radioactive Materials Handling Facility (RMHF) Complex * # * # * # * # * # * # # * * # * # * # Subarea 7 * # * # * # * # * # * # * # * # # * * * # # * # * # * # # * * # * # * # * # * # * # 4056 Landfill * # * # # * *# # *# * # * # * # * * # # * *# # * # * # *# *# * * # * # ** # 4614 * # # * # # * * # * # * # * # * # * # Building 4009 Leachfield * # * # * # * # * # * # * # * # * # 4059 * # 4059 4626 4062 * # * # * # * # * # * # * # 4100 * # * # * # Arnes * # s F ir e Rd. * # * # * # * # * # * # * # * # * # * # * # # * * # * # # * * # * # * # * # * # * # * # 4314 * # * # * # * # * # 4814 * # * # * # * # H St * # * # * # # # * * * # * # *# # *# * * # * # 4318 # * * # # * * * # * # # * # 4425 * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * * # # * # * # * # # * * # # * * # * # * # * # * # * # * # Subarea 5A Building 4029 * # * # * # L85 Nuclear Experimentation Reactor - Building 4093 * # h St . Kinetics Experiment Water Boiler - Former Building 4073 * # Former Building 4023 * # Former Building 4005 * # * # Heavy Metal Likely Remediation Zone 4383 Inset Subarea 5B G St. * # 4374 * # 4848 * * # * # # * # * 4373 # * * # # * # * # * # * # # * # * * # J St. 4055 * # * # 4015 * # # * * # # * * # * 4353 # * # * # # * * # I St. * # * # * # * # * # * # * # * # * # * # * # * # * # * # Subarea 8 South Radioactive Materials Handling Facility Complex Plutonium Development Facility Building 4055 * # * # * # * # Outfall #3 Former Building 4353 * # Pond Dredge Area Former Buildings 4173/4865 * # Site 4614 RMHF Holdup Pond/Catchment * # Basin * # Subarea 5D South * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # * # 4621 * # * # * * # # 4103 4083 * # 4663 * # * # * # * # * # * # # * * # * *# # * # # * Below FAL * # (Below 0.0466 pCi/g) (Below 0.0162 pCi/g) FAL to less than 2 times FAL # * (0.0466 to 0.0931 pCi/g) (0.0162 to 0.0323 pCi/g) 2 times to less than 3 times FAL # * (0.0932 to 0.139 pCi/g) (0.0324 to 0.0485 pCi/g) 3 times to less than 4 times FAL # * (0.140 to 0.185 pCi/g) (0.0486 to 0.0647 pCi/g) Greater than 4 times FAL # * (0.186 to x.xxx pCi/g) (0.0648 to x.xxxx pCi/g) Likely Remediation Zones Chemical (as of 5/2012) Structures Existing Removed There were no samples which corresponded to the boxed symbol. * # * # * * # # * # 4825 * # # * * # * # * # t. ES * # 4014 * # * # L85 Nuclear Experimentation Reactor Building 4093 * # 4035 * # * # * # 4046 * # * # * # 4064 * # 4641 * # Shield Test Irradiation Reactor Kinetics Experiment #* * # Water Boiler * # Former Building 4073 4036 4625 * # 4037 * # * # * # * # * # * * # # GS t. 11th St. * # * # HGL—Radiological Characterization of Soils in Area IV and NBZ, Santa Susana Field Laboratory—Ventura County, California Figure 4.14 Curium-243/244 Round 1 and 2 Surface Soil and Sediment Results Santa Susana Field Laboratory Area IV and NBZ Radiological Study Roads Approximate Drainage Pathways 20-foot elevation contours * # 4027 4024 Subareas * # * # Legend TAL (FAL = 0.0162) * # * # * # * # * # 4025 GEL (FAL = 0.0466) * # * # # * 4010 Curium-243/244 * # * # * # 4021 * # * # * # * # * # 4664 4075 * # Sodium Reactor Experiment Complex * # * # * # * # * # * # 4665 * # Interim Storage Facility Building 4654 4022 * # # * * # * # * # * # St. * # * # * # * # * # * # # * * # # * * # * # * # * # * # * # * # * *# # * # * # 4693 * # * # # * * # * # * # 10th * # * # * # * # * # * ## * * # * # * # * # * *# # * # * # * # * # * # * # * # * # * # Engineering Test Building * # Former Building 4003 4003 * # * # * # * # * # 4143 * # * # * # * # * # * # * # * # * # * # * # * # * # 4724 * # * # *# # * * # * # * # * # * # * # * # # # * * *# * # * # RMHF Leachfield Hot Oil Sodium Cleaning Facility * # * # 4163 * # * # # * *# # * * # * # * # * # * # * # * # * # * # * # ** # # * # * # * # * # 4723 * # * # # * * # * # * # * # * # * # * # # * * # * # Former Buildings 4375 and 4875 * # * # * # * # * # Hot Lab - Former Building 4020 * # * # * # # * * * # *# # # * * # * # * * # # # * # * * * # # * # # * # * # * * # * # * *# # * # * # SRE Dam * # * # * # * # * # * # * # 4373 Leach Field * # * # * # * # * # * # Hazardous Waste Management Facility Building 4133 * # * # * # * # * # * # * # * # * # * # * # * # Subarea 5D North * # * # * # * # * # * # * # * # * # * # Fast Critical Experiment Building 4100 * # * # * # * # * # * # * # Building 4015 4353 * # * # Subarea 5C * # * # # * * # * # * # * # * # * # # # * * * # * * # # # * # * * # * # * # * * # # * # * # * 4363 # # * * # * # * # * # * # Building 4019 * # 4874 * ## ** # *# * # * # * # * # * # * # Building 4011 * # SRE Pond * # Former Building 4356 4015 * # Liquid and Gas Radioactive Storage Tanks Subarea 7 Northern Panhandle Building 4006 * # 4055 * # 17th Street Drainage * # * # * # Fuel Element Storage Facility * # * # 4482 4487 # * * # * # * # * # * # * # 4483 * # * # * # * # * # 4484 4485 * # # * 4875 * # * # * # Engineering Test Building Former Building 4003 * # * # * # * # * # * # * # * # * # 4462 * # * # * # S t. * # 4483 * # * # * # * # * # * # * # * # * # * # * # # * # * * # * * # * # *# # * # * # * # * * # # * # 4020 # * # * * # # * * # *# # *# * * # * # 4020 * # * * # * # # * # *# * * # *# # * * # * # # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * * # # 4486 4462 * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # 4011 4487 * # * # * # * # * ## * 4461 * # 4009 * # * # * # * # * # * # * # * # * # * # * # S t. * # 4383 4009 * # * # * # * # * # * # * # 4066 4100 * # * * # # * # New Conservation Yard Drainage * # * # 22nd St. * # * # * # 4463 24th St. * # 4065 * # * # * # 4066 4462 4100 4100 * # * # * # Old Conservation Yard * # * # 4486 * # * # 4065 F St. 24th St. * # * # * # * # # * # * * 4064# # * # * * # * # * # # * # * 4064 * # # * * # * # * * # *# # 4011 4463 4885 * # * # * # * # t 18 . * # St * # 12 th * # 17th St. # * * * # # * # * # * # * # * # * # 4038 4038 * # 4609 * # * # # * * # * # * # * * # # * # * # * # * # * # # * * 4023 # 4042 4005 h * # * # * # * # 4816 * # * # * # * # * # # * * # 4006 4038 * # * # 4035 * # ## * * 4042 4626 * # * # Subarea 6 * # * # t 20 * # * # 4040 * # * # G 4005 4057 4626 * # * # * # * # * # * # * 4014 # * # 4046 4093 * # * # * # # * * # 4037 * ## * * *# # * # * # * # * # t. . * # * # St * # * # * # * # 4037 4032 4057 * # * # ES 4027 4026 4039 * # * # 4825 * # * # * # h * # * # * # 4826 * # * # * # 4036 * # 4023 4026 4026 4356 * # * # # * * ## * * # # * # * * # * # * * # # # * *# *# # *# * 4641 4641 4027 ## * * * # * # # * * # t 17 * # 4625 4024 4006 4356 * # * # # * * # 4355 4362 * # * # * # 4083 4028 * # * # * # * # 17th St. 4019 * # * # # * * # * # * # 4641 4019 * # * # * # * # 4003 * # 4073 4013 * # * # 4003 * # * # * # * * # # ## * * 4032 4013 * # * # * # # * 4693 * # * # 4663 * # # ** # 4025 * # * # * # * # 4621 * # * # F St. * # 4025 * # * # * # 4103 4228 * # Empire State Atomic Development Associates (ESADA) * # * # * # 4010 * # * # Former Sodium Disposal Facility * # * # * # * # * # * # 4021 * # 4143 4041 * # 4022 4075 * # * # * # 11th St. * *# # * # * # 4665 4654 # * * # * # *# # * # * * # * * # * ## 4664 4024 * # * # * # * # * # 4163 S t. Sodium Graphite Reactor/ Organic Moderated Reactor Building 4009 * ## * * ## * * ## * * # * # # * * # # * # * * # * # * # # * *# # * h 10t * # * # *# # # * * *# * # # * * # * # * # * # 4724 * # * # ## * * *# * # * # * # # * * *# # * # # * * # * # * 4163 # * 4003 # * # * # * # * # # 4133 ** # # * * # * # * # * # * # 4143 * # * # ## * * * # * # * # * # * # * # * * # # * # # # # * * * SRE Dam * # * # * # # # * * SRE Dam # * * # * # * # * # * # * # * # * # 4723 * # * # * # # * * * # * * # *# # *# # * # # # * * **# * # *# # * # # * ** * # # * # # # * *# * # *# # * * # * # * *# # * *# # *# # * 4143 # * * # * # * # * # ## * * * * # ## * * # * # * # * # * # * # * # * # * # * # Southern California Edison Substation * # * # * # * # * # * # * # See Inset Northern Buffer Zone West * # * # * # * # SNAP Experimental Reactor Facility Former Building 4010 * # # * * # * # # * Shield Test Irradiation Reactor * # * # * # * * # # Subarea 8 North * # Subarea 3 * # * # * # * # * # * # Outfall #3 # * * # Notes: FAL - Field action level GEL - GEL Laboratories, Inc KEWB - Kinetics Experiment Water Boiler NBZ - Northern Buffer Zone SNAP - Systems Nuclear Auxiliary Power TAL - Test America Laboratories RMHF - Radioactive Materials Handling Facility pCi/g - picocuries per gram 0 250 ³ 500 Feet U.S. EPA Region 9 1000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\FAL_Plates\ Fig4-14_Cm-243-244_Surface.mxd 12/19/2012 pbillock Boeing 2011, HGL 2012 Northern Buffer Zone East * # * # * # * # Sodium Reactor Experiment (SRE) Complex * # * # * # * # St. 3r d Radioactive Materials Handling Facility (RMHF) Complex * # * # * # * # # * * # * # * # * # Subarea 7 * # * # * # Outfall #3 * # * # # * * * # # Northern Buffer Zone West * # * # # ** # * # * # * # * # # * * # * # # ** # # # * * * # * # * # * # * # Subarea 8 North * # * # * # *# # * *# * # * # # * * # * # * # * # * # * # * # * # * # * # * # 4010 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # 4013 * # * # * # * # * # 4059 * # * # * # * # * # F St. * # 4693 * # * # # * * # * # E 4083 4040 * # * # # * 4046 4093 * # 4641 4641 4036 4027 # * * # # * 4037 * # # 4064# * * * * # # * # * # # * # * 4064 * # Old Conservation Yard 4037 * # * 4032# # * 4032 * # * # * # G # * # * *4023# # * # * # * *# # * * 4023 # * # * # S t. Engineering Test Building Former Building 4003 11th St. 12 th 17th St. S t. * # * # 4042 4042 * # * # * # * # * # Subarea 5A h * # St . Building 4029 * # * # 4038 4038 L85 Nuclear Experimentation Reactor - Building 4093 * # h St 4062 t 18 . * # 4065 4066 4065 4066 * # * # * # 4100 # * # * * # * # * # 4100 4100 s F ir e Rd. * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # H St * # * # * # # * * # * # 4814 * # * # # * * # * # * # 4314 * # * # * # * # * # * # * # * # # # * * * # *# # *# * * # 4318 * # * * # # * # * # * 4425 # # * * # * # * * # # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # # * * # * # * # * # * # 4055 * # * # # * * # 4015 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # Radioactive Materials Handling Facility Complex Outfall #3 Pond Dredge Area * # Former Buildings 4173/4865 * # * # * # # * * # # * * * # # # * ** * # # # * # * # * # * # * # * # * # * # * # * # * # Shield Test Irradiation Reactor 4621 4103 4021 4083 4663 * # * *# # * # * # Below FAL * # TAL (FAL = 0.0162) (Below 0.0466 pCi/g) (Below 0.0162 pCi/g) FAL to less than 2 times FAL # * (0.0466 to 0.0931 pCi/g) (0.0162 to 0.0323 pCi/g) 2 times to less than 3 times FAL # * (0.0932 to 0.139 pCi/g) (0.0324 to 0.0485 pCi/g) 3 times to less than 4 times FAL # * (0.140 to 0.185 pCi/g) (0.0486 to 0.0647 pCi/g) Greater than 4 times FAL # * (0.186 to x.xxx pCi/g) (0.0648 to x.xxxx pCi/g) Subareas Likely Remediation Zones Chemical (as of 5/2012) Structures Existing Removed There were no samples which corresponded to the boxed symbol. * # * # 4014 * # * # * # * # 4046 * # * # * # 4064 * # * # * # 4641 * # # * * * ## * # # * * # *# # *# * * # * # # * * # * # * # * # * # 4036 4625 * # 4037 * # * # Kinetics Experiment Water Boiler Former Building 4073 * # * # * # GS 4027 4024 * # * # * # * # t. 11th St. * # * # HGL—Radiological Characterization of Soils in Area IV and NBZ, Santa Susana Field Laboratory—Ventura County, California Figure 4.15 Curium-243/244 Round 1 and 2 Subsurface Soil and Sediment Results Santa Susana Field Laboratory Area IV and NBZ Radiological Study Roads Approximate Drainage Pathways 20-foot elevation contours * * # # * # # * * # * # * # 4025 GEL (FAL = 0.0466) * # * # 4035 * # 4010 Curium-243/244 * # * # * # Legend * # t. ES L85 Nuclear Experimentation Reactor Building 4093 * # * # * # * # * # * # St. * # * # * # * # 10th * # * # # * * # * # * # 4664 4075 * # * # * # # * * # * # * # * # * # * # 4022 * # * # * # * # * # # * * # * # * # * # * # 4693 * # 4665 * # * # * # * # * # * # * # # * * # * # * # * # Subarea 5D South * # * # # * # # * # * * 4825 Interim Storage Facility Building 4654 * # # * * # * # * # * # Sodium Reactor Experiment Complex * # * # # * * # * # * # *# # * * # * # * # * # * # * # 4003 * # * # Engineering Test Building * # Former Building 4003 * # * # * # * # * # * # * # * # * # * # * # * # * # * # Hot Oil Sodium Cleaning Facility * # * # * # * # * # * # 4163 * # 4143 * # * # # * *# * # * # * # * # * # * # * ## * * * # # *# * # # * * * # * # # *# # * * # * # * # * # * # * # * # * # * # * # 4724 * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # Site 4614 RMHF Holdup Pond/Catchment * # Basin * # * # # * * * # # * # * # * # * # * # Former Buildings 4375 and 4875 * # * # * # * # RMHF Leachfield * # * # * # * # * # * # * *# # * # * # * # * # * # Hot Lab - Former Building 4020 * # * # * # * # * # Former Building 4353 * # * # * # 4723 * # * # * # * # * # * # * # # * Hazardous Waste Management Facility Building 4133 Plutonium Development Facility Building 4055 * # Subarea 8 South * # # * * # * # 4373 Leach Field * # * # * # * # # * * # * # SRE Dam * # * # * # * # * # * # * # * # * # * # * # * # * # * # Subarea 5D North * # * # * # * # * # * # * # * # * # * # Fast Critical Experiment Building 4100 * # * # * # * # * # * # Building 4015 # * * # # * 4353 * # # * * # * # I St. * # * # # * * # Subarea 5C 4353 * # * # * # * # * # * # * # * # * # * # * # * # * # Building 4019 * # SRE Pond * # Building 4011 * # Liquid and Gas Radioactive Storage Tanks * # Former Building 4356 4015 * # 4874 Subarea 7 Northern Panhandle Building 4006 * # 4374 * # * # 4848 * # * * # # * # * 4373 # * * * # # * # # * # * # * # * # * # * # J St. 4055 * # 17th Street Drainage * # * # * # * # # * * # * # * # * # * # * # * # * # # * * # * # * # * # # * * # * # * # * # * # * # # * * * # # * * # # * * # * # # * # * # * # # * * # * # # * * # * 4363 # * # * # # * Subarea 5B G St. * * * # ## ** # # *# 4875 # * * # * # * # * # * # 4383 * # * # * # * # * # * # * # * # * # * # * # # * # * * # * * # * # *# # * # * # * # * * # # * # 4020 # * # * * # # * * # *# # *# * * # * # 4020 * # * * # * # # * # *# * * # *# # * * # * # # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # # * * # * # * # * # * # * # * # 4487 * # * # Inset 4461 * # 4009 * # * # 4482 4487 * # Heavy Metal Likely Remediation Zone 4483 4383 * # * # Former Building 4005 4484 4485 4100 * # 4009 * # * # * # Former Building 4023 * # * # 22nd St. * # * # * # * # 4462 * # * # Arnes Kinetics Experiment Water Boiler - Former Building 4073 4483 * # * * # # * # * # * # 4486 4462 24th St. * # * # . 4011 4462 4463 24th St. * # * # * # St 4486 4463 * # * # h * # F St. 4609 4885 * # Fuel Element Storage Facility * # t 17 4626 * # * # New Conservation Yard Drainage * # t 20 * # * # # * * # 4011 * # * # * * # # * # * # # * * # 4641 * # * # * # * # * # * # 4038 * # * # Subarea 6 * # * # * # # * * # * # * # * # # * * # * 4014 # * # * # * # * # * # * * # # * ## * 4626 * # * # * # * # S t. * # * # # * * # 4057 4626 * # * # * # 4005 4057 * # * # * # * # * # # * * # * # # * * # * # ## ** # *# * * # # * * # * # * # 4816 * # * # * # * # * # * # * # 4826 4039 * # * # * # * # * # 4825 4026 4356 * # * # * # 4006 4026 4026 4356 *# # * * # * # * # 4035 4073 4005 * # * *# # 4059 * # * # * # * # * # 4006 * # * # * # 4027 4024 * # # * *# # * * # 4724 4003 # * * # * # # * 4003 * # * # * # *# # *# * * # * # * # 4003 4654 * ## * *# # * * # * # * * # # * # 4625 * # 4163 * # * # * # 4024 * # * # * # * # 4663 * # * # # * SRE Dam # * * # 4723 * # * # * # * *# # * 4143 # * *# # # * * *# *# *# * # *# # * # * # 4143 # * # * * 4143 # * # # * # # * # * * * # * # * * # * # # 4041 * # * * # # 4103 * # 4355 * # * 4163 # * # * # * # * # * # SRE Dam # * * # * # # * * # * # # * * * # # * # * # *# # *# * *# #* ** # * * # # *# *# # * # * # * * # # * * # # 4022 4019 4362 * # * # * # * # * # 17th St. 4019 * # * # 4013 * # * # * # * # * # # * * # # * 4665 4025 * # * # * ## * * # * # 4021 * # 4228 * # # * * # * # *# # * 4664 * # 4025 * # * # * # * # S t. * # * # * # * # * # * # Southern California Edison Substation * # * # h 10t * # * # * # * # # * 4075 # * * # *# # *# * # *# * * * # # *# *# # * 4614 4621 * # # * * # * # * # * # * # * # * # * # *# # * # * # * *# # *# ** # * # * # * # * # *# # * * 4028 # * # * # * # * # * # # * * # * # * * # # * # * # * # # * * # *# # *# * * # * # * # * # * # * # # 4133 ** # # * * # * # * # * # * # * # * # # * * # * # * # * # * # # * * # * # * # * # * # * # * # # * * # * # * # * # * # Empire State Atomic Development Associates (ESADA) * # * # * # Former Sodium Disposal Facility * # Subarea 3 * # * # * # * # SNAP Experimental Reactor Facility Former Building 4010 Sodium Graphite Reactor/ Organic Moderated Reactor Building 4009 * # * # * # * # Building 4009 Leachfield * # * # # * * # * # # * See Inset Shield Test Irradiation Reactor 4056 Landfill * # * # * # * ## * * # * # * # * # * # * # # * * # * # Notes: FAL - Field action level GEL - GEL Laboratories, Inc KEWB - Kinetics Experiment Water Boiler NBZ - Northern Buffer Zone SNAP - Systems Nuclear Auxiliary Power TAL - Test America Laboratories RMHF - Radioactive Materials Handling Facility pCi/g - picocuries per gram 0 250 ³ 500 Feet U.S. EPA Region 9 1000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\FAL_Plates\ Fig4-15_Cm-243-244_Subsurface.mxd 12/19/2012 pbillock Boeing 2011, HGL 2012 Northern Buffer Zone East Sodium Reactor Experiment (SRE) Complex St. 3r d Radioactive Materials Handling Facility (RMHF) Complex Subarea 3 Subarea 7 Southern California Edison Substation Outfall #3 See Inset Shield Test Irradiation Reactor SNAP Experimental Reactor Facility Former Building 4010 SRE Dam 4723 4724 Northern Buffer Zone West 4163 F St. 4143 4003 4693 4133 4825 4654 Subarea 8 North ES t. 4014 Subarea 6 4040 4665 4056 Landfill 4664 4021 4075 4614 Building 4009 Leachfield 4621 Old Conservation Yard 4035 4103 4022 4083 4663 4093 4046 New Conservation Yard Drainage 4064 4073 4641 4036 4625 S t. Sodium Graphite Reactor/ Organic Moderated Reactor Building 4009 h 10t 4028 4037 4027 4024 G S t. Engineering Test Building Former Building 4003 11th St. 4010 4025 4023 Former Sodium Disposal Facility 12 th 17th St. S t. 17th St. 4013 4042 4019 Empire State Atomic Development Associates (ESADA) Fuel Element Storage Facility 4005 4362 4006 4356 4026 4059 4826 Subarea 5A 4816 4039 t 17 h St . 4057 Building 4029 4626 4038 L85 Nuclear Experimentation Reactor - Building 4093 t 20 h St 4062 . t 18 h St . Kinetics Experiment Water Boiler - Former Building 4073 Former Building 4023 4066 4065 Former Building 4005 4011 F St. 4609 4486 4885 24th St. 4463 4462 Heavy Metal Likely Remediation Zone 4483 4485 4482 4487 4100 4484 4461 4383 Subarea 5B G St. s F ir e Building 4006 Rd. 4015 4373 H St 22nd St. 4848 SRE Pond SRE Dam Former Building 4356 4374 4055 4020 Liquid and Gas Radioactive Storage Tanks Subarea 7 Northern Panhandle 17th Street Drainage 4009 Arnes Inset Building 4011 Building 4019 4723 J St. Subarea 5C 4425 4874 4814 4314 4318 4875 24th St. 4353 4363 I St. Building 4015 Fast Critical Experiment Building 4100 Hazardous Waste Management Facility Building 4133 Subarea 5D North 4373 Leach Field Plutonium Development Facility Building 4055 Subarea 8 South Engineering Test Building Former Building 4003 4143 Radioactive Materials Handling Facility Complex 4693 Sodium Reactor Experiment Complex RMHF Leachfield Outfall #3 Hot Lab - Former Building 4020 4825 Interim Storage Facility Building 4654 Former Buildings 4375 and 4875 Former Buildings 4173/4865 4163 4003 Former Building 4353 Pond Dredge Area Hot Oil Sodium Cleaning Facility 4724 Site 4614 RMHF Holdup Pond/Catchment Basin t. ES 4014 4665 4664 4103 4022 4021 4075 Subarea 5D South 4621 L85 Nuclear Experimentation Reactor Building 4093 4083 4663 4035 4046 4064 4641 Kinetics Experiment Water Boiler Former Building 4073 4036 4625 GS 4027 4024 HGL—Radiological Characterization of Soils in Area IV and NBZ, Santa Susana Field Laboratory—Ventura County, California 4025 Select Radionuclides of Concern, Surface and Subsurface Below FAL One or more radionuclides equal or greater than FAL Both Laboratories Subareas Likely Remediation Zones Chemical (as of 5/2012) Structures Existing Removed Figure 5.1 Select Radionuclides of Concern Round 1 and 2 Surface and Subsurface Soil and Sediment Results Santa Susana Field Laboratory Area IV and NBZ Radiological Study Roads Approximate Drainage Pathways 20-foot elevation contours t. 11th St. 4010 Legend St. 4037 10th Shield Test Irradiation Reactor Notes: FAL - Field action level NBZ - Northern Buffer Zone SNAP - Systems Nuclear Auxiliary Power RMHF - Radioactive Materials Handling Facility pCi/g - picocuries per gram Select radionuclides include: Americium-241, Curium-243/244, Cesium-137, Cobalt-60, Europium-152, Europium-154, Nickel-59, Plutonium-238, Plutonium-239/240, Tritium, and Strontium-90 0 250 ³ 500 Feet U.S. EPA Region 9 1000 Y:\Santa_Susana\EP9038\Soil_Sampling\Report\FAL_Plates\ Fig5-1_SelectROC.mxd 12/19/2012 pbillock Boeing 2011, HGL 2012