Preliminary Assessment/Site Inspection Report Santa Susana Field Laboratory Simi Valley, California EPA ID No.: CAN000908498 USACE Contract No.: W91238-06-F-0083 Document Control No.: 12767.063.419.1650 November 30, 2007 Prepared for: U.S. Environmental Protection Agency Region 9 Prepared by: Weston Solutions, Inc. 1575 Treat Blvd, Suite 212 Walnut Creek, CA 94598 Santa Susana Field Laboratory PA/SI Report TABLE OF CONTENTS Section Page 1.0 INTRODUCTION ...............................................................................................................1 1.1 Apparent Problem ....................................................................................................1 2.0 SITE DESCRIPTION ..........................................................................................................2 2.1 Location ...................................................................................................................2 2.2 Site Description........................................................................................................2 2.3 Operational History..................................................................................................3 2.4 Regulatory Involvement ..........................................................................................4 2.4.1 U.S. Environmental Protection Agency...................................................................4 2.4.2 U.S. Department of Energy......................................................................................4 2.4.3 California Department of Toxic Substances Control...............................................4 2.4.4 California Regional Water Quality Control Board..................................................5 2.4.5 California Department of Health Services - Radiological Health Branch...............5 3.0 INVESTIGATIVE EFFORTS .............................................................................................6 4.0 HAZARDOUS RANKING SYSTEM FACTORS..............................................................6 4.1 Sources of Contamination........................................................................................6 4.2 Groundwater Pathway..............................................................................................7 4.2.1 Hydrogeological Setting ..........................................................................................7 4.2.2 Groundwater Targets ...............................................................................................8 4.2.3 Groundwater Pathway Conclusion ..........................................................................9 4.3 Surface Water Pathway............................................................................................9 4.3.1 Hydrologic Setting.................................................................................................10 4.3.2 Surface Water Pathway Targets.............................................................................10 4.3.3 Surface Water Pathway Conclusion.......................................................................10 4.4 Soil Exposure and Air Pathways ...........................................................................10 4.4.1 Physical Conditions ...............................................................................................11 4.4.2 Soil and Air Targets...............................................................................................11 4.4.3 Soil Exposure and Air Migration Pathway Conclusions .......................................11 5.0 EMERGENCY RESPONSE CONSIDERATIONS ..........................................................12 6.0 SUMMARY.......................................................................................................................12 7.0 REFERENCE LIST ...........................................................................................................14 ii Santa Susana Field Laboratory PA/SI Report List of Tables Table 3-1. Primary Waste Facilities at the SSFL site .............................................................16 List of Figures Figure 2-1. Site Location Map..................................................................................................19 Figure 2-2. Site Layout Map.....................................................................................................20 Appendix A Transmittal List B Site Reconnaissance Interview and Observation Report/Photographic Documentation C Contact Log and Contact Reports D Latitude and Longitude Calculations Worksheet E References F EPA Quick Reference Fact Sheet: (Site Assessment: Evaluating Risks at Superfund Sites) iii Santa Susana Field Laboratory PA/SI Report List of Acronyms AOCs Areas of Concern APTF Advanced Propulsion Test Facility BBI Brandeis-Bardin Institute Boeing The Boeing Company CEQA California Environmental Quality Act CERCLA Comprehensive Environmental Response, Compensation, and Liability Act CERCLIS Comprehensive Environmental Response, Compensation, and Liability Information System CMS Corrective Measures Study DHS-RHB California Department of Health Services – Radiological Health Branch DOE Department of Energy ECL Engineering Chemical Labortory EIS Environmental Impact Statement ETEC Energy Technology and Engineering Center FSDF Former Sodium Disposal Facility HRS Hazard Ranking System LETF Laser Engineering Test Facility LOX liquid oxygen MCL Maximum Contaminant Level MMH monomethyl hydrazine NASA National Aeronautics and Space Administration NPDES National Pollutant Discharge Elimination System NPL National Priorities List NTO nitrogen tetroxide OUs Operable Units PA/SI Preliminary Assessment/Site Inspection ppb parts per billion RCRA Resource Conservation and Recovery Act RFA RCRA Facility Assessment RFI RCRA Facility Investigation RIHL Rockwell International Hot Laboratory RMDF Radioactive Materials Disposal Facility RWQCB California Regional Water Quality Control Board SARA Superfund Amendments and Reauthorization Act SMMC Santa Monica Mountain Conservancy SNAP Space Nuclear Auxiliary Power SRE Sodium Reactor Experiment SSFL Santa Susana Field Laboratory STL-IV Systems Testing Laboratory IV SWMUs Solid Waste Management Units TCE trichloroethylene TSDF treatment, storage, and disposal facility iv Santa Susana Field Laboratory PA/SI Report EPA Environmental Protection Agency WESTON Weston Solutions, Inc. v Santa Susana Field Laboratory PA/SI Report 1.0 INTRODUCTION Under the authority of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) and the Superfund Amendments and Reauthorization Act of 1986 (SARA), Weston Solutions, Inc. (WESTON) was tasked to conduct a Preliminary Assessment/Site Inspection (PA/SI) of the Santa Susana Field Laboratory (SSFL) site, located approximately 2 miles south of the City of Simi Valley and 29 miles northwest of downtown Los Angeles, California, on a plateau near the crest of the Simi Hills. The purpose of the PA/SI is to review existing information and collect additional information on the site and its environs using the U.S. Environmental Protection Agency=s (EPA=s) Hazard Ranking System (HRS) criteria to assess the relative threat associated with actual or potential releases of hazardous substances at the site. The HRS has been adopted by the EPA to help set priorities for further evaluation and eventual remedial action at hazardous waste sites. The HRS is the primary method of determining a site=s eligibility for placement on the National Priorities List (NPL). The NPL identifies sites at which the EPA may conduct remedial response actions. This report summarizes the findings of these preliminary investigative activities. The SSFL site (EPA ID No.: CAN000908498) was identified as a potential hazardous waste site and entered into the Comprehensive Environmental Response, Compensation, and Liability Information System (CERCLIS) in 1980. EPA has conducted investigations at various locations throughout the site. The individual locations were assigned separate EPA ID numbers. In April, 2007, EPA ID No.: CAN000908498 was created as a parent site to the various SSFL sites (i.e., CA3890090001 - Energy Technology Engineering Center, CA1800090010 – Rockwell International – Rocketdyne Division (NASA), CAD093365435 – Rockwell International Corporation Rocketdyne Division, CAD982399776 – Rockwell International Corporation – SSFL II, CAD982399719 – Rockwell International Corporation – SSFL I). All of the SSFL locations have been combined into this parent site in order to allow EPA to evaluate the entire site as a single entity (1). More information about the Superfund program is available on the EPA web site at http://www.epa.gov/superfund. The fact sheet attached in Appendix F describes EPA=s site assessment process. 1.1 Apparent Problem The apparent problems at the site, which contributed to EPA=s determination that a PA/SI was necessary, are presented below: • Multiple operations at the SSFL over the last six decades have resulted in the contamination of surface and subsurface environmental media by various hazardous substances. • Extensive use of the most predominant hazardous substance at the site, trichloroethylene (TCE), has impacted the groundwater beneath the site. Several TCE plumes exist 1 Santa Susana Field Laboratory PA/SI Report throughout the site. • Drinking water wells at the site were contaminated with TCE and shut down after workers were exposed to TCE concentrations above Federal and State limits (2, 3, 4).