DOE/EIS-0402 January 2017 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Summary U.S. Department of Energy Office of Environmental Management AVAILABILITY OF THE DRAFT ENVIRONMENTAL IMPACT STATEMENT FOR REMEDIATION OF AREA IV AND THE NORTHERN BUFFER ZONE OF THE SANTA SUSANA FIELD LABORATORY (Draft SSFL Area IV EIS) For further information on this Draft SSFL Area IV EIS, or to request a copy, please contact: Ms. Stephanie Jennings, NEPA Document Manager SSFL Area IV EIS U.S. Department of Energy 4100 Guardian Street, Suite 160 Simi Valley, CA 93063 Telephone: 1-805-842-3864 Printed with soy ink on recycled paper COVER SHEET Lead Agency: U.S. Department of Energy (DOE), Office of Environmental Management Cooperating Agencies: National Aeronautics and Space Administration (NASA), U.S. Army Corps of Engineers, and the Santa Ynez Band of Chumash Indians Title: Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory (Draft SSFL Area IV EIS) (DOE/EIS-0402) Location: Ventura County, California For further information or for copies of this Draft SSFL Area IV EIS, contact: Ms. Stephanie Jennings NEPA Document Manager SSFL Area IV EIS U.S. Department of Energy 4100 Guardian Street, Suite 160 Simi Valley, CA 93063 Telephone: 1-805-842-3864 For general information on the DOE National Environmental Policy Act (NEPA) process, contact: Carol M. Borgstrom, Director Office of NEPA Policy and Compliance, GC-54 U.S. Department of Energy 1000 Independence Avenue, SW Washington, DC 20585-0103 Telephone: 202-586-4600, or leave a message at 1-800-472-2756 This document is available on the SSFL Area IV EIS website (http://SSFLAreaIVEIS.com) and the DOE NEPA website (http://energy.gov/nepa) for viewing and downloading. Abstract: This Draft SSFL Area IV EIS analyzes the potential environmental impacts of alternatives for conducting cleanup activities in Area IV of the Santa Susana Field Laboratory (SSFL) and the adjoining Northern Buffer Zone (NBZ), located in Ventura County, California. Remediation is needed to clean up residual chemicals and radionuclides from historical DOE operations at the Energy Technology Engineering Center (ETEC) in Area IV, in compliance with regulations, orders, and agreements. The alternatives analyzed in this draft environmental impact statement (EIS) involve the disposition of remaining DOE facilities and support buildings, remediation of soil and groundwater, and disposal of all resulting waste at existing licensed or permitted facilities in a manner that is protective of the environment and the health and safety of the public and workers. The information in this EIS will inform decision-makers and the public about the potential impacts of the proposed cleanup of both chemicals and radionuclides and will be considered along with other relevant factors in making decisions regarding cleanup of Area IV and the adjoining NBZ. DOE is proposing three sets of alternatives. Each set was developed to address a component of the SSFL Area IV and NBZ cleanup effort: soil remediation, building demolition, and groundwater remediation. Preferred Alternative: DOE has no preferred alternative at this time. iii Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Public Involvement: DOE conducted a number of activities to encourage public input and assist the public in its role in the NEPA process. Following issuance of an Advance Notice of Intent to prepare a draft EIS in October 2007 (72 Federal Register [FR] 58834), DOE held informal discussions with the public and stakeholders to gather information used in preparing the Notice of Intent (NOI) published in May 2008 (73 FR 28437). During this first scoping period, DOE held six scoping public meetings to present the proposed alternatives and receive comments from agencies, organizations, and the public. DOE held scoping meetings in Simi Valley, Northridge, and Sacramento, California. In spring 2012, DOE sponsored three Community Alternative Development Workshops, in which community members were asked to articulate their preferences for alternatives that they would like to see included in this EIS. In consideration of site characterization activities conducted by DOE and the U.S. Environmental Protection Agency and changes in cleanup requirements (as a result of the 2010 Administrative Order on Consent for Remedial Action between DOE and the California Department of Toxic Substances Control), DOE published an Amended NOI in February 2014 (79 FR 7439), announcing a second scoping period from February to April 2014. During this second scoping period, DOE held two public scoping meetings, one each in Simi Valley and Agoura Hills, California, and a scoping meeting with Native American tribal members. DOE considered comments provided during both scoping periods, as well as input received from the 2012 Community Alternatives Development Workshops, in the preparation of this draft EIS. Comments on this Draft SSFL Area IV EIS should be submitted within 60 days of the publication of the U.S. Environmental Protection Agency’s Notice of Availability of this draft EIS in the Federal Register to ensure consideration in preparation of the Final SSFL Area IV EIS. DOE will consider comments received after the 60-day comment period to the extent practicable. Written comments may be submitted to Ms. Stephanie Jennings via U.S. mail to the address provided above or electronically, via a comment portal on the SSFL Area IV EIS website (http://SSFLAreaIVEIS.com). DOE will hold public hearings on this draft EIS during the comment period. DOE will announce the dates, times, and locations of these hearings via newspaper advertisements, the SSFL Area IV EIS website, the DOE NEPA website, and notifications to persons on the mailing list. Information on this EIS can be found at http://SSFLAreaIVEIS.com or http://energy.gov/nepa. iv Table of Contents Table of Contents List of Figures ....................................................................................................................................... vi List of Tables ........................................................................................................................................ vi Acronyms and Abbreviations ............................................................................................................... vii S.1 Introduction .............................................................................................................................. S-1 S.2 Purpose and Need for Agency Action ...................................................................................... S-2 S.3 Proposed Action........................................................................................................................ S-2 S.4 History of the Site ..................................................................................................................... S-2 S.5 Future of Area IV and the Northern Buffer Zone..................................................................... S-6 S.6 Cooperating Agencies ............................................................................................................... S-6 S.7 Decisions to Be Supported ....................................................................................................... S-6 S.8 Public Involvement ................................................................................................................... S-7 S.9 Organization of this Environmental Impact Statement ........................................................... S-9 S.10 Alternatives ............................................................................................................................. S-10 S.10.1 S.10.2 S.10.3 S.10.4 S.10.5 S.11 Alternatives Development ............................................................................................................................S-11 S.10.1.1 Applicable Laws, Regulations, Orders, and Agreements .................................................S-11 S.10.1.2 Process and Criteria ................................................................................................................S-12 S.10.1.3 Alternative Concepts Considered but Dismissed from Detailed Study ........................S-16 Soil Remediation Alternatives ......................................................................................................................S-16 S.10.2.1 Soil No Action Alternative ....................................................................................................S-16 S.10.2.2 Cleanup to AOC Look-Up Table Values Alternative .......................................................S-16 S.10.2.3 Additional Soil Remediation Action Alternatives ..............................................................S-30 S.10.2.4 Summary of Soil Remediation Alternatives ........................................................................S-34 Building Demolition Alternatives ................................................................................................................S-42 S.10.3.1 Background ..............................................................................................................................S-42 S.10.3.2 Building No Action Alternative ............................................................................................S-42 S.10.3.3 Building Removal Alternative ...............................................................................................S-42 Groundwater Remediation Alternatives .....................................................................................................S-44 S.10.4.1 Background ..............................................................................................................................S-44 S.10.4.2 Groundwater No Action Alternative ...................................................................................S-45 S.10.4.3 Groundwater Monitored Natural Attenuation Alternative .............................................S-47 S.10.4.4 Groundwater Treatment Alternative ...................................................................................S-48 Preferred Alternative ......................................................................................................................................S-48 Summary of Potential Environmental Consequences ............................................................ S-48 S.11.1 S.11.2 S.11.3 Comparison of Potential Environmental Consequences of Alternatives .............................................S-48 Potential Environmental Consequences of Combined Action Alternatives........................................S-70 Summary of Potential Cumulative Impacts ...............................................................................................S-87 S.12 Conclusions............................................................................................................................. S-97 S.12.1 S.12.2 S.12.3 Areas of Potential Controversy ....................................................................................................................S-97 Issues to Be Resolved ....................................................................................................................................S-99 Major Conclusions....................................................................................................................................... S-100 S.13 References .............................................................................................................................. S-103 v Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory List of Figures Figure S–1 Figure S–2 Figure S–3 Figure S–4 Figure S–5 Figure S–6 Figure S–7 Figure S–8 Figure S–9 Project Location, Santa Susana Field Laboratory ..................................................................................................... S-3 Santa Susana Field Laboratory and Surrounding Communities ............................................................................ S-3 EIS Public Involvement Opportunities ..................................................................................................................... S-8 Extent of Radiological and Chemical Constituents Above AOC Look-Up Table Values .............................S-20 Extent of Radiological and Chemical Constituents Above AOC Look-Up Table Values with Proposed Exemption Areas ..............................................................................................................................S-22 Soil Remediation – Cleanup to Revised LUT Values Alternative with Proposed Exemption Areas ...........S-32 Soil Remediation – Conservation of Natural Resources Alternative with Proposed Exemption Areas .......................................................................................................................................S-35 Remaining Structures in Area IV ...............................................................................................................................S-43 Area IV Groundwater Plumes ...................................................................................................................................S-46 List of Tables Table S–1 Table S–2 Table S–3 Table S–4 Table S–5 Table S–6 Table S–7 Table S–8 Table S–9 Matrix of Alternative Concepts Considered but Dismissed from Detailed Study ...........................................S-17 Preliminary Estimated Soil Volumes for Remedial Actions per 2010 AOC Considerations .........................S-19 Preliminary Estimated Soil Volumes for Transportation ......................................................................................S-24 Remediation Soil Quantities and Truck Traffic by Alternative ............................................................................S-39 DOE Truck Round Trips by Year for Remediation Alternatives .......................................................................S-40 Estimated DOE Area IV Building Demolition Materials .....................................................................................S-44 Summary of Potential Environmental Consequences under the Soil Remediation Alternatives ..................S-49 Summary of Potential Environmental Consequences under the Building Demolition Alternatives ............S-59 Summary of Potential Environmental Consequences under the Groundwater Remedial Alternatives ....................................................................................................................................................................S-64 Table S-10 Summary of Potential Cumulative Impacts .............................................................................................................S-88 vi Acronyms and Abbreviations Acronyms and Abbreviations ALARA AOC BMP Boeing BTV CEQ CEQA CFR CFWS CMWD CNEL CO CO2 dBA D&D DOE DTSC EA EIR EIS EPA ESAL ETEC FAL FONSI FR FSDF HMSA LCF LLW LOS LUT MCL MDC MLLW NAAQS NASA NBZ NEPA NNSS NOI NOX NPDES NRHP PAH PCB PCE as low as reasonably achievable Administrative Order on Consent for Remedial Action best management practice The Boeing Company Background Threshold Value Council on Environmental Quality California Environmental Quality Act Code of Federal Regulations California Fish and Wildlife Service Calleguas Municipal Water District community noise equivalent level Consent Order for Corrective Action carbon dioxide decibels A-weighted decontamination and decommissioning U.S. Department of Energy Department of Toxic Substances Control environmental assessment environmental impact report environmental impact statement U.S. Environmental Protection Agency equivalent single-axle load Energy Technology Engineering Center field action level Finding of No Significant Impact Federal Register Former Sodium Disposal Facility Hazardous Materials Storage Area latent cancer fatality low-level radioactive waste level of service Look-Up Table maximum contaminant level minimum detectable concentration mixed low-level radioactive waste National Ambient Air Quality Standards National Aeronautics and Space Administration Northern Buffer Zone National Environmental Policy Act Nevada National Security Site Notice of Intent nitrogen oxides National Pollutant Discharge Elimination System National Register of Historic Places polycyclic aromatic hydrocarbon polychlorinated biphenyl perchloroethylene vii Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory PM2.5 PM10 RBSL RCRA RFI RMHF ROD ROI SHPO SRAIP SRAM SRE SSFL SO2 TCE TPH USFWS VOC viii particulate matter less than 2.5 microns in diameter particulate matter less than 10 microns in diameter risk-based screening level Resource Conservation and Recovery Act RCRA Facility Investigation Radioactive Materials Handling Facility Record of Decision region of influence State Historic Preservation Officer Soils Remedial Action Implementation Plan Final Standardized Risk Assessment Methodology Revision 2 Addendum, Santa Susana Field Laboratory, Ventura County, California Sodium Reactor Experiment Santa Susana Field Laboratory sulfur dioxide trichloroethylene total petroleum hydrocarbons U.S. Fish and Wildlife Service volatile organic compound Acronyms and Abbreviations CONVERSIONS Multiply METRIC TO ENGLISH by Area Square meters Square kilometers Square kilometers Hectares Concentration Kilograms/square meter Milligrams/liter Micrograms/liter Micrograms/cubic meter Density Grams/cubic centimeter Grams/cubic meter Length Centimeters Meters Kilometers Radiation Sieverts Temperature Absolute Degrees C + 17.78 Relative Degrees C Velocity/Rate Cubic meters/second Grams/second Meters/second Volume Liters Liters Liters Cubic meters Cubic meters Cubic meters Cubic meters Weight/Mass Grams Kilograms Kilograms Metric tons To get Multiply ENGLISH TO METRIC by To get 10.764 247.1 0.3861 2.471 Square feet Acres Square miles Acres Square feet Acres Square miles Acres 0.092903 0.0040469 2.59 0.40469 Square meters Square kilometers Square kilometers Hectares 0.16667 1a 1a 1a Tons/acre Parts/million Parts/billion Parts/trillion Tons/acre Parts/million Parts/billion Parts/trillion 0.5999 1a 1a 1a Kilograms/square meter Milligrams/liter Micrograms/liter Micrograms/cubic meter 62.428 0.0000624 Pounds/cubic feet Pounds/cubic feet Pounds/cubic feet Pounds/cubic feet 0.016018 16,018.5 Grams/cubic centimeter Grams/cubic meter 0.3937 3.2808 0.62137 Inches Feet Miles Inches Feet Miles 2.54 0.3048 1.6093 Centimeters Meters Kilometers 100 Rem Rem 0.01 Sieverts 1.8 Degrees F Degrees F - 32 0.55556 Degrees C 1.8 Degrees F Degrees F 0.55556 Degrees C 2118.9 7.9366 2.237 Cubic feet/minute Pounds/hour Miles/hour Cubic feet/minute Pounds/hour Miles/hour 0.00047195 0.126 0.44704 Cubic meters/second Grams/second Meters/second 0.26418 0.035316 0.001308 264.17 35.314 1.3079 0.0008107 Gallons Cubic feet Cubic yards Gallons Cubic feet Cubic yards Acre-feet Gallons Cubic feet Cubic yards Gallons Cubic feet Cubic yards Acre-feet 3.7854 28.316 764.54 0.0037854 0.028317 0.76456 1233.49 Liters Liters Liters Cubic meters Cubic meters Cubic meters Cubic meters 0.035274 2.2046 0.0011023 1.1023 Ounces Ounces Pounds Pounds Tons (short) Tons (short) Tons (short) Tons (short) ENGLISH TO ENGLISH 28.35 0.45359 907.18 0.90718 Grams Kilograms Kilograms Metric tons Acre-feet 325,850.7 Gallons Gallons 0.000003046 Acres 43,560 Square feet Square feet 0.000022957 Square miles 640 Acres Acres 0.0015625 a. This conversion is only valid for concentrations of contaminants (or other materials) in water. Acre-feet Acres Square miles METRIC PREFIXES Prefix exapetateragigamegakilodecadecicentimillimicronanopico- Symbol E P T G M k D d c m μ n p Multiplication factor 1,000,000,000,000,000,000 1,000,000,000,000,000 1,000,000,000,000 1,000,000,000 1,000,000 1,000 10 0.1 0.01 0.001 0.000 001 0.000 000 001 0.000 000 000 001 = = = = = = = = = = = = = 1018 1015 1012 109 106 103 101 10-1 10-2 10-3 10-6 10-9 10-12 ix Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory This page left blank intentionally x Summary S.1 Introduction The U.S. Department of Energy (DOE) prepared this Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory (Draft SSFL Area IV EIS) in accordance with the National Environmental Policy Act (NEPA) and Council on Environmental Quality (CEQ) and DOE implementing regulations at Title 40, Code of Federal Regulations, Parts 1500-1508 (40 CFR Parts 1500-1508) and 10 CFR Part 1021, respectively. Past activities at the Santa Susana Field Laboratory (SSFL), Ventura County, California, resulted in chemical and radiological releases that impacted soil, buildings, and groundwater. Residual chemicals and radionuclides from historical operations in Area IV associated with soil, buildings, and groundwater, as well as soil contamination in the Northern Buffer Zone (NBZ) that is contiguous to and emanating from Area IV, need to be cleaned up. Extensive soil sampling and analysis in recent years has demonstrated that the chemical contamination is more widespread than the radiological contamination, and that contaminants are concentrated near certain facilities, rather than being evenly distributed across the site. This environmental impact statement (EIS) analyzes the potential environmental impacts of alternatives for conducting cleanup activities in Area IV and the NBZ. There are separate alternatives for soil remediation, building demolition, and groundwater remediation. For soil remediation, DOE’s proposed action is to implement the technical requirements of the 2010 Administrative Order on Consent for Remedial Action (2010 AOC) (DTSC 2010a) between DOE and the California Department of Toxic Substances Control (DTSC)—that is, cleanup to meet the LookUp Table (LUT) values for residual concentrations of chemicals and radionuclides in soil established in accordance with the 2010 AOC (Cleanup to AOC LUT Values Alternative). In preparing this EIS, DOE identified challenges to implementing this alternative, including difficulty determining when the AOC LUT values have been met and difficulty finding replacement soil that meets the AOC LUT values. Consistent with NEPA requirements, this EIS also analyzes a no action alternative (no soil treatment or removal), as well as two additional action alternatives (Cleanup to Revised LUT Values Alternative and Conservation of Natural Resources Alternative). The additional action alternatives would meet the cleanup objectives to be protective of the environment and the health and safety of the public and workers while avoiding some of the technical challenges and potential adverse environmental impacts associated with cleanup to the 2010 AOC LUT values. For buildings, DOE’s proposed action is to demolish the 18 structures it owns in Area IV and dispose of or recycle the materials off site (Building Removal Alternative); the EIS also analyzes a no action alternative of leaving the structures in place. To address groundwater contamination, this EIS analyzes current levels of monitoring (no action), additional monitoring to better support natural attenuation (Groundwater Monitored Natural Attenuation Alternative), and active treatment of contaminated groundwater (Groundwater Treatment Alternative). This EIS will inform Federal decisions about remediation of contaminated soil and groundwater, building demolition, restoration of the impacted environment, and disposal of chemical and radioactive waste. DOE’s conclusions resulting from the evaluation of alternatives in this EIS are presented in Section S.10 of this Summary. DOE does not have a preferred alternative and looks forward to receiving input from the public on this draft EIS. This EIS also responds to an order by the U.S. District Court for the Northern District of California, which permanently enjoins DOE from transferring possession or otherwise relinquishing control over any portion of Area IV until DOE has completed an EIS and issued a Record of Decision (ROD). This Order Granting Plaintiffs’ Motion for Summary Judgment (Case 3:04-CV-04448-SC, S-1 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory May 2, 2007) is the result of a lawsuit filed by the Natural Resources Defense Council, the Committee to Bridge the Gap, and the City of Los Angeles, which successfully challenged DOE’s 2003 Final Environmental Assessment for Cleanup and Closure of the Energy Technology Engineering Center (ETEC EA) (DOE 2003) and Finding of No Significant Impact (FONSI) for remediation of Area IV. DOE issued an Advance Notice of Intent to prepare an EIS and conduct public involvement activities in the October 17, 2007, Federal Register (FR) (72 FR 58834). A Notice of Intent (NOI) to prepare this EIS was published in May 2008 (Notice of Intent to Prepare an Environmental Impact Statement for Remediation of Area IV of the Santa Susana Field Laboratory and Conduct Public Scoping Meetings [73 FR 28437]). Due to the availability of more-recent site characterization data and issuance of the 2010 AOC, DOE held a second scoping period in 2014 that was initiated by the Amended Notice of Intent to Prepare an Environmental Impact Statement for Remediation of Area IV of the Santa Susana Field Laboratory and Conduct Public Scoping Meetings, (79 FR 7439) published February 7, 2014. S.2 Purpose and Need for Agency Action DOE needs to complete remediation of Area IV and the NBZ to comply with applicable requirements for cleanup of radiological and hazardous substances. These requirements include regulations, orders, and agreements. To this end, DOE needs to remove the remaining DOE structures in Area IV of SSFL and clean up the affected environment in Area IV and the NBZ in a manner that is protective of the environment and the health and safety of the public and workers. S.3 Proposed Action DOE proposes to remove existing DOE-owned facilities and support buildings from Area IV (Building Removal Alternative); remediate chemically and radiologically impacted soil in Area IV and the NBZ (Cleanup to AOC LUT Values Alternative); remediate groundwater in Area IV and the NBZ (elements of the Groundwater Monitored Natural Attenuation and Groundwater Treatment Alternatives); dispose of resulting waste; and restore the affected environment in accordance with applicable laws, orders, regulations, and agreements with the State of California. S.4 History of the Site Located in Ventura County, California, on approximately 2,850 acres in the hills between Chatsworth and Simi Valley, SSFL was developed as a remote site to test rocket engines and conduct nuclear research (Figure S–1). Rockwell International’s Rocketdyne Division (based in Canoga Park, California) began rocket engine testing in the Area I portion of SSFL in 1947. Rockwell created Atomics International in the early 1950s to conduct nuclear research in Area IV for the Atomic Energy Commission (a predecessor agency of DOE) and commercial entities. In 1996, Rockwell International sold its aerospace and defense business, including Area IV of SSFL, to The Boeing Company (Boeing). S-2 Summary Figure S–1 Project Location, Santa Susana Field Laboratory SSFL is divided into four administrative areas and two contiguous buffer zones north and south of the administrative areas. Figure S–2 shows SSFL and the surrounding communities, including the layout of SSFL (Areas I, II, III, and IV and the adjacent buffer zones) and land ownership. The majority of Area I is owned and operated by Boeing. Area II and a 42-acre parcel within Area I are owned by the Federal Government and administered by the National Aeronautics and Space Administration (NASA). Areas III, IV, and the contiguous buffer zone areas to the north and south are owned by Boeing. DOE does not own any land at SSFL, but is the owner of 18 buildings in Area IV and is responsible for building demolition and cleanup of soils and groundwater in Area IV and the NBZ. Figure S–2 Santa Susana Field Laboratory and Surrounding Communities Starting in the mid-1950s, the Atomic Energy Commission funded nuclear energy research on a 90-acre parcel of land in what is now SSFL Area IV, which was leased from Rocketdyne. The Energy Technology Engineering Center (ETEC) was established by the Atomic Energy Commission on this parcel in the early 1960s as a ‘‘center of excellence’’ for liquid metals research (primarily S-3 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory sodium, potassium, and mercury) and general metals compatibility testing. In support of that mission, DOE built and operated 10 small nuclear reactors for various research activities over the years. As a result of operating these research reactors and conducting nuclear research, chemicals and radionuclides were released into the soil, bedrock, and groundwater. As part of the operations of a research and development site, structures were constantly used, cleaned, and refurbished for a new purpose or demolished. Cleanup activities have been ongoing since the 1960s. DOE decontaminated and demolished several of its structures and facilities in Area IV to the standards in effect at the time decommissioning occurred (see, for example, the discussion of prior cleanup in Section S.10.2.2, under 2010 AOC Soil Cleanup Standards), in accordance with its authority under the Atomic Energy Act of 1954, as amended. The major periods of building demolition were 1975 through 1977 and 1995 through 2005. By 1980, all reactor operations had ceased, and nuclear research at ETEC was terminated in 1988. DOE has removed all nuclear materials from the site. By the time non-nuclear liquid metals research ended in 1998, many facilities had been decontaminated, decommissioned, and demolished, and contaminated materials had been removed. As appropriate, these activities were covered by categorical exclusions, in accordance with DOE’s “NEPA Implementing Regulations” (10 CFR Part 1021, Appendix B to Subpart D). In the early 2000s, DOE decided to prepare an environmental assessment (EA) for the remaining cleanup activities. An EA is used to assess whether a proposed Federal action would have significant impacts on the environment. DOE issued the ETEC EA (DOE 2003) in March 2003. The ETEC EA evaluated the potential impacts of implementing additional cleanup and closure activities, including decontaminating and decommissioning the remaining sodium facility and other support facilities. DOE issued a FONSI for the EA on March 31, 2003, and began cleanup activities by undertaking limited building demolition. In October 2004, the Natural Resources Defense Council, the Committee to Bridge the Gap, and the City of Los Angeles challenged the ETEC EA and FONSI in a Federal district court, claiming DOE had violated NEPA; the Comprehensive Environmental Response, Compensation, and Liability Act; and the Endangered Species Act. In May 2007, the court issued its Order Granting Plaintiffs’ Motion for Summary Judgment (Case 3:04-CV-04448-SC, May 2, 2007), which permanently enjoins DOE from transferring possession or otherwise relinquishing control over any portion of Area IV until DOE has completed an EIS and issued a ROD pursuant to NEPA. DOE suspended physical demolition and removal activities for its remaining facilities at ETEC, except for those activities necessary to maintain the site in a safe and stable configuration, until completion of the final EIS and ROD. In 2007, DTSC issued the Consent Order for Corrective Action (2007 CO) (DTSC 2007) to DOE, NASA, and Boeing (as respondents), pursuant to DTSC’s authority over hazardous waste under the California Health and Safety Code, Section 25187. The 2007 CO requires the respondents to clean up all chemically contaminated soils1 and groundwater at SSFL to risk-assessment-based levels. The risk-assessment-based levels are based on a suburban resident scenario established for SSFL in the Final Standardized Risk Assessment Methodology Revision 2 Addendum, Santa Susana Field Laboratory, Ventura County, California (SRAM) (MWH 2014),2 which assumed a receptor would be present on the site 24 hours per day, 350 days per year, for 30 years. The 2007 CO required further The 2010 AOC (DTSC 2010a) superseded the 2007 CO (DTSC 2007) with respect to cleanup of chemically and radioactively impacted soils; however, it incorporated the 2007 CO by reference for groundwater remediation. The 2010 AOC also added building demolition. 2 The 2007 CO cited a 2005 version of the SRAM Work Plan. The currently applicable version of the SRAM (MWH 2014) was issued in 2014. 1 S-4 Summary characterization of the nature and extent of contamination at SSFL and identified the Resource Conservation and Recovery Act (RCRA) studies and work plans that would be prepared. The 2007 CO requires:  cleanup of chemically contaminated soils by June 30, 2017, using the 2005 SRAM Work Plan (Rev. 2);  implementation of DTSC-approved groundwater and unsaturated zone cleanup remedies in the Chatsworth Formation Operable Unit by June 30, 2017, or earlier; and  completion of construction of the DTSC-approved long-term soil cleanup remedy in the surficial media operable unit by June 30, 2017, or earlier. The SRAM (MWH 2014) describes a risk-assessment methodology for determining the areas that would need remediation. A hypothetical future suburban residential land use was identified for the evaluation of risk; other plausible receptors (such as recreational users or workers) were also identified. In 2010, DOE entered into the 2010 AOC (DTSC 2010a) with DTSC. The 2010 AOC superseded the 2007 CO with respect to soil remediation and changed the framework for the soils characterization and cleanup process for Area IV and the NBZ.3 The 2010 AOC stipulated that the soils cleanup standard would be based on LUT values, which are: (1) for chemicals, local background concentrations or method detection limits4 for those chemicals whose method detection limits exceed local background concentrations, and (2) for radionuclides, local background concentrations or minimum detection limits for radionuclides whose detection limits exceed local background concentrations. The 2010 AOC defines the minimum detection limit for a radionuclide as the smallest amount of activity that can be quantified for comparison with regulatory limits.5 The 2010 AOC indicates that, for soil remediation decisions, DOE is to compare the concentration of any chemical or radionuclide in each individual sample (not an average of samples in an area) with its respective LUT value. Thus, any soil samples that do not meet the LUT values for all chemicals or radionuclides would require a cleanup action to be taken. The 2010 AOC (DTSC 2010a) identified characterization activities for both chemical and radiological contaminants and requires DOE to prepare a Soils Remedial Action Implementation Plan (SRAIP)6 describing where soil cleanup will occur, any areas proposed for exemptions to protect biological or cultural resources, and any areas proposed for in situ or onsite treatment to The 2007 CO remains in effect for groundwater remediation. Per the 2010 AOC, “detection limit” means the method reporting limit, which is the lowest concentration at which an analyte can be confidently detected in a sample and its concentration can be reported with a reasonable degree of accuracy and precision. 5 In its Final Technical Memorandum, Look-Up Table Recommendations, Santa Susana Field Laboratory Area IV Radiological Study (HGL 2012b), EPA stated: “In exercising independent technical judgment, as identified in Section 5.2 of the 2010 AOC (DTSC 2010a), EPA recommends an adjustment to the BTVs [background threshold values] and minimum detectable concentrations [limits] (MDCs) to include appropriate consideration for [method uncertainty] to ensure an acceptably low decision error rate of approximately 5 percent. This adjustment is not believed by EPA to be contrary to the 2010 AOC requirement that LUT values incorporate BTVs and laboratory MDCs.” The memorandum also stated: “For purposes of this technical memorandum, and for the appropriate use of BTVs, it is important to note that the MDC is not used as a detection decision criterion. Rather, the MDC is understood to represent a level of activity at which the associated uncertainty becomes predictably constrained to a level that is useful for defining a substitute cleanup value when the BTV is not practically or technologically supported by the laboratory data. The use of the MDCs in this case, defined as “the smallest amount of activity that can be quantified for comparison with regulatory limits,” is consistent with the 2010 AOC requirements and definitions.” 6 The 2010 AOC requires DOE to prepare a SRAIP that includes a site description and history and a description of the nature and extent of radiological and chemical contamination, planned remedial actions, proposed exemptions, proposed areas for onsite treatment, proposed mitigations to address environmental impacts, and schedule. DOE may prepare multiple SRAIPs to address different implementation phases. DOE anticipates submitting the first of three planned SRAIPs to DTSC at the same time that DTSC issues the final program environmental impact report. 3 4 S-5 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory achieve cleanup goals. The 2010 AOC specifies that no “leave-in-place” alternative (onsite burial or landfill) is allowed. Chemicals and radionuclides in soil brought in as backfill also must meet the LUT values. Verification of cleanup levels and the acceptability of the backfill are required by DTSC for chemicals and by the U.S. Environmental Protection Agency (EPA) for radioactive constituents. The 2010 AOC also specifies that the SRAIP shall include a schedule that ensures that the identified (soil cleanup) activities can be accomplished by 2017 or sooner (see Section S.12). Due to a number of factors, as discussed in Chapter 2, Section 2.2.3, soil cleanup by 2017 is not possible under any action alternative. Not all of the energy research conducted in Area IV was performed for DOE; some energy research was performed by Boeing and its predecessors for other customers. DOE has responsibility for cleanup of soils in the 290-acre Area IV. DOE shares responsibility with NASA for cleanup of soil in the 182-acre NBZ; NASA is responsible for cleanup of contamination in the NBZ that emanates from areas that it administers (DTSC 2010b). DOE shares responsibility with Boeing for groundwater remediation in Area IV and the NBZ, as defined in the 2007 CO (DTSC 2007). Boeing is responsible for management decisions regarding the Area IV buildings it owns. S.5 Future of Area IV and the Northern Buffer Zone Boeing is the landowner of Area IV and the NBZ; therefore, Boeing will decide the potential future land use of these areas. Boeing has stated that its intent is to maintain its portion of SSFL (including Area IV and the NBZ) as undeveloped open space. Further, Boeing states that it would restrict future land use to prevent development for any commercial, industrial, agricultural, or residential purpose. Boeing also states that it would restrict future land use to ensure the property would be protected as undeveloped open space, regardless of zoning changes beyond its control (Boeing 2016b). Boeing has indicated it is committed to cleanup to a standard that is equivalent to a suburban residential standard that is more protective of human health than that applicable to open space uses (Boeing 2016b). S.6 Cooperating Agencies CEQ NEPA regulations (40 CFR 1501.6) establish the requirements for cooperating agencies (see text box). For this EIS, there are three cooperating agencies: NASA, the U.S. Army Corps of Engineers, and the Santa Ynez Band of Chumash Indians (a federally recognized Native American tribe with historical ties to the SSFL land). EPA and DTSC were also invited to be a cooperating agency, but declined. S.7 Decisions to Be Supported Cooperating Agencies (from 40 CFR 1508.5) “Cooperating agency means any Federal agency other than a lead agency that has jurisdiction by law or special expertise with respect to any environmental impact involved in a proposal (or a reasonable alternative) for legislation or other major Federal action significantly affecting the quality of the human environment. The selection and responsibilities of a cooperating agency are described in 40 CFR 1501.6. A State or local agency of similar qualifications or, when the effects are on a reservation, an Indian Tribe, may by agreement with the lead agency become a cooperating agency.” DOE is proposing to remove existing DOE-owned facilities and support buildings, remediate radiologically and chemically impacted soil and groundwater, dispose of the resulting waste, and restore the affected environment. The 2007 CO (DTSC 2007), which is applicable to groundwater, requires a risk-based cleanup approach based upon the methodology in the SRAM (MWH 2014) that was approved by DTSC. The 2010 AOC (DTSC 2010a) requires soil cleanup to LUT values. These two DTSC Orders S-6 Summary specify how the cleanup standards are to be developed for SSFL Area IV soil and groundwater remediation. This EIS evaluates reasonable alternatives for how DOE can conduct the cleanup of Area IV and the NBZ. DOE has developed separate reasonable alternatives for the three components that make up its remediation project: soil remediation, building demolition, and groundwater remediation. As required by CEQ NEPA regulations (40 CFR 1508.25), DOE is also evaluating no action alternatives for soil remediation, building demolition, and groundwater remediation. For each component of its remediation project, DOE may select one of the alternatives described in this EIS, or DOE may combine different aspects of the alternatives and create a “hybrid” alternative. The potential environmental impacts presented in this EIS, along with public input, cost, policy, and other factors, will be considered by DOE decision-makers in selecting alternatives for soil remediation, building demolition, and groundwater remediation for implementation. DOE’s decision resulting from the analysis in this EIS will be announced in a ROD that will be issued no sooner than 30 days after the EPA Notice of Availability for the Final EIS is published in the Federal Register. S.8 Public Involvement DOE considers public involvement to be a critical element in the cleanup and closure of SSFL and has incorporated extensive public involvement opportunities for the planning activities it is conducting related to cleanup of Area IV and the NBZ. DOE has complied with the spirit and intent of NEPA public involvement requirements by implementing public involvement efforts seeking to include all SSFL stakeholders. SSFL stakeholders have expressed varying, and sometimes conflicting and competing, points of view. DOE’s efforts to enhance its interactions with the community began in earnest in 2008 when it commissioned interviews of SSFL stakeholders representing the range of perspectives among community members. These interviews revealed, among other issues, concerns about the completeness of the historical information available about the site. These observations and concerns are documented in Report on Community Interviews: Community Concerns and Preferences for Public Participation in Cleanup of Area IV Santa Susana Field Laboratory (P2 Solutions 2009). Using the community interviews as a foundation, DOE prepared the Community Involvement Plan Area IV Santa Susana Field Laboratory in 2010 (DOE 2010). The plan describes how DOE provides timely, accurate, and credible information and/or access to information to the public, agencies, and organizations that are interested in and may be affected by the SSFL remediation and closure process. It also describes DOE plans to continue to provide opportunities for public contributions to selected project issues, reports, plans, and other project documents that DOE will use in its decision-making process. In addition, the plan describes the overarching objectives of building and improving relationships with regulators, elected officials, and the affected public; fostering a coordinated approach to address cleanup; and evaluating DOE activities to modify and enhance public participation (DOE 2010). A principal component of the NEPA process is active public participation (see Figure S–3). DOE has conducted a number of activities to encourage public input in the NEPA process. DOE’s NEPA regulations require a public meeting for scoping and a public hearing for a draft EIS (10 CFR 1021.311 and 1021.313, respectively). The regulations also require a minimum 30-day scoping comment period and a minimum 45-day public comment period on a draft EIS. These NEPA public involvement opportunities are described below. S-7 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory The purpose of scoping-related public involvement activities is to inform the public about an EIS early in the process and obtain public input on issues of concern and development of alternatives. DOE issued an Advance Notice of Intent to prepare an EIS in October 2007. Scoping was initially conducted in 2008; however, because of changed soil remediation requirements resulting from the 2010 AOC (DTSC 2010a) and the availability of more-recent site characterization data, DOE issued an Amended NOI (79 FR 7439) and conducted another public scoping period in 2014. During the 2008 Draft SSFL Area IV EIS scoping period from May to August, DOE held six scoping meetings to present the proposed alternatives and receive comments from agencies, organizations, and the public. The scoping meetings were held in Simi Valley, Northridge, and Sacramento, California. DOE received 750 individual comments from 74 commenters, including individuals; elected officials; special interest groups; and Federal, state, and local agencies during the 2008 scoping period. The comments are documented in the Scoping Comment Responses for the Environmental Impact Statement for Remediation of Area IV of the Santa Susana Field Laboratory (DOE 2009). Figure S–3 EIS Public Involvement Opportunities In spring 2012, DOE sponsored three Community Alternatives Development Workshops in which the community was asked to articulate their preferences for alternatives that they would like to see included in this EIS. DOE presented information on how alternatives are developed and what criteria they need to meet. Stakeholders then broke into groups and developed alternatives to be considered by DOE. The 2014 scoping period announced in the February 2014 Amended NOI ended on April 2, 2014. DOE held scoping meetings in Simi Valley and Agoura Hills/Calabasas, California. Over the 55-day scoping period, DOE received a total of 1,272 comments from 309 commenters, including individuals, an elected official, organizations, Government agencies, a Native American organization, and a Native American tribe. Information on scoping and comments received is included in the 2014 Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Final Scoping Summary Report (DOE 2014a). DOE reviewed the comments provided during the 2008 and 2014 scoping periods and the 2012 Community Alternatives Development Workshops. DOE developed alternatives for this EIS based, in part, on input from the stakeholders. Summary documents of comments received during these scoping efforts, along with information on additional EIS-related public involvement activities, are available on the ETEC website at: http://etec.energy.gov/Char_Cleanup/EIS.html. S-8 Summary S.9 Organization of this Environmental Impact Statement This EIS consists of 14 chapters and supporting appendices. The chapters and appendices are organized as follows:  Chapter 1, “Introduction,” describes DOE’s purpose and need for action, background history for SSFL Area IV, decisions to be supported, related NEPA documents, and public involvement through the NEPA process.  Chapter 2, “Alternatives,” describes the range of reasonable alternatives for remediation of Area IV and the NBZ, as well as the alternatives that were considered but eliminated from detailed study in this EIS. It also presents a summary of the potential environmental impacts by alternative.  Chapter 3, “Affected Environment,” describes the potentially affected environments at Area IV and the NBZ. These data are provided as the baseline against which the potential impacts of each of the alternatives can be compared.  Chapter 4, “Environmental Consequences,” describes the potential impacts of the alternatives. Environmental consequences were evaluated for each alternative for the same resources areas described in Chapter 3.  Chapter 5, “Cumulative Impacts,” describes the potential cumulative impacts of the action alternatives in combination with other past, present, and reasonably foreseeable future actions. The chapter presents information regarding the cumulative impacts of DOE, NASA and Boeing activities, as well as the cumulative impacts from other activities in the region.  Chapter 6, “Measures to Minimize Impacts and Mitigation Measures,” provides information on planned measures to minimize potential impacts, as well as potential methods of mitigating impacts under the action alternatives.  Chapter 7, “Resource Commitments,” addresses sustainability, potential unavoidable adverse impacts to the environment, irreversible and irretrievable commitments of resources, and short-term impacts versus long-term productivity of Area IV and the NBZ from implementing the action alternatives.  Chapter 8, “Laws, Regulations, and Other Requirements,” describes the environmental and health and safety compliance requirements governing implementation of the alternatives.  Chapter 9, “Native American Histories and Perspectives,” describes the significance of SSFL to the native peoples who inhabited the site before it began operations as a field laboratory.  Chapters 10, 11, 12, 13, and 14 are the “References,” “Glossary,” “Index,” “List of Preparers,” and “Distribution List” chapters, respectively.  Appendices are included to provide more-detailed information to support this EIS. - Appendix A, “Federal Register Notices” - Appendix B, “Environmental Consequences Methodologies” - Appendix C, “Alternatives Development” - Appendix D, “Detailed Project Information” - Appendix E, “Consultations” S-9 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory - Appendix F, “Cultural Resources” - Appendix G, “Human Health” - Appendix H, “Evaluation of Transportation and Traffic Impacts” - Appendix I, “Wetlands Assessment” - Appendix J, “Cost-Benefit Analysis Report” - Appendix K, “Contractor Disclosure Statement(s)” S.10 Alternatives This section describes the reasonable alternatives for remediation of SSFL Area IV and the NBZ. DOE is evaluating separate alternatives for soil remediation, building demolition, and groundwater remediation. DOE proposes to complete remediation of Area IV and the NBZ to comply with applicable requirements for cleanup of chemical and radioactive constituents. Orders, regulations, and agreements affecting the development of this EIS include, but are not limited to, the Order Granting Plaintiffs’ Motion for Summary Judgment from the lawsuit challenging DOE’s 2003 ETEC EA (DOE 2003) and FONSI (see Section S.4); the CEQ and DOE NEPA regulations; the 2010 AOC (DTSC 2010a), and the 2007 CO (DTSC 2007). This section further discusses these requirements and explains how they informed the development of action alternatives analyzed in this EIS. Whereas the development of alternatives for building demolition and groundwater remediation was straightforward, the alternatives for soil remediation evolved as DOE considered comments from the public and cooperating agencies (Chumash 2014) and evaluated the complexities of implementing soil cleanup in accordance with the 2010 AOC. It is important for decision-makers, people living near SSFL, and other stakeholders to understand the process DOE employed in identifying the soil remediation alternatives evaluated in this EIS. DOE considered a number of soil remediation alternatives, informed by public input. After entering into the 2010 AOC, DOE developed an action alternative for soil remediation that implemented the technical requirements of that consent order—that is, cleanup to meet the LUT values for residual concentrations of chemicals and radionuclides in soil established in accordance with the 2010 AOC. DTSC published LUT values for 116 chemicals and provisional LUT values for 16 radionuclides in 2013 (see Appendix D, Section D.2). In accordance with the 2010 AOC, these LUT values are generally meant to limit contaminants remaining in soil after cleanup to local background levels, considering technical limitations in the measurement of these constituents in soil. As data on levels of chemical and radioactive constituents in soil at Area IV, the NBZ, and background locations7 became available and the AOC LUT values were established, DOE recognized that there would be technical issues (see Evaluation of Implementation of 2010 AOC Cleanup Requirements in Section S.10.2.2) associated with implementing a cleanup that meets the 2010 AOC requirements. DOE also determined that implementing the 2010 AOC requirements and remediating soil to meet the AOC LUT values would have the potential for adverse environmental impacts due to the large area of land that would be disturbed and the large volume of soil that would be removed. The CEQ NEPA regulations state that an EIS “shall provide full and fair discussion of significant environmental impacts and shall inform [decision-makers] and the public of the reasonable alternatives which would avoid or minimize adverse impacts or enhance the Background reference areas located 3 to 6 miles from SSFL were identified to be representative of SSFL onsite soil conditions. Soils and sediments in these areas were sampled and analyzed to establish chemical and radiological background levels (HGL 2011; URS 2012). 7 S-10 Summary quality of the human environment” (40 CFR 1502.1). The Santa Ynez Band of Chumash Indians, a cooperating agency on this EIS, also expressed their expectation that DOE would include “a robust analysis of alternatives” (Chumash 2014). DOE therefore determined that it was necessary to develop additional action alternatives for soil remediation that were protective of human health and the environment to be analyzed in this EIS. Evaluation of additional soil remediation alternatives allows decision-makers and the public to compare the potential impacts from implementing the alternatives with those from implementing a cleanup that meets the 2010 AOC requirements. For purposes of comparison, the soil remediation action alternatives evaluated in this EIS address remediation of the soil in Area IV and the NBZ to AOC LUT values for chemicals and radionuclides, revised LUT values for chemicals (that is, LUT values that are based on individual chemical risk), or risk-assessment-based values for chemicals and radionuclides (expressed as a radiation dose for radionuclides). The building demolition action alternative (i.e., the Building Removal Alternative) addresses removal of the remaining DOE-owned buildings in Area IV and disposal of the debris off site. The groundwater remediation action alternatives address implementation of management practices to clean up groundwater in accordance with the requirements of the 2007 CO (DTSC 2007). Each of the three sets of alternatives allows independent evaluation and comparison of the potential impacts of implementing each component of DOE’s cleanup action. In addition, DOE evaluated the potential combined impacts of implementing each of the three cleanup components: soil remediation, building demolition, and groundwater remediation. Under all alternatives, steps would be taken to protect biological and cultural resources, including limiting the amount of soil disturbance in biologically or culturally sensitive areas as provided for in the 2010 AOC. To the extent practicable, and as approved by DTSC, DOE would use onsite treatment and natural attenuation to reduce the volume of soil that would be transported and disposed of off site. Soil in which chemical constituents would not attenuate (degrade) naturally on site to levels meeting cleanup criteria would be transported off site to permitted disposal facilities based on the type of waste. Locations where soil is excavated would be backfilled, re-contoured, and stabilized with new vegetation. To the extent practicable, DOE would implement green remediation technologies and revegetate with native species. A no action alternative is included for each of the three sets of alternatives. Evaluation of a no action alternative is required in accordance with CEQ NEPA regulations (40 CFR 1502.14(d)) because it establishes the baseline against which the potential environmental impacts of the action alternatives can be compared. S.10.1 Alternatives Development This section presents the alternatives development process, as well as a discussion of regulatory drivers, community involvement, and the alternative concepts that were considered, but dismissed from detailed analysis. S.10.1.1 Applicable Laws, Regulations, Orders, and Agreements Removal of existing DOE-owned facilities and support buildings from Area IV, remediation of chemically and radiologically impacted soil and groundwater in Area IV and the NBZ, disposal of resulting waste, and restoration of the affected environment would be conducted in accordance with applicable laws, regulations, and orders and agreements with the State of California. The 2007 CO (DTSC 2007), which applies to groundwater in Area IV and the NBZ, calls for a risk-based cleanup S-11 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory approach for groundwater based on the methodology in the SRAM (MWH 2014)8 that was approved by DTSC. The 2010 AOC (DTSC 2010a) requires soil cleanup to the AOC LUT values, which are based on soil background levels or method/minimum detection limits. DOE expects that, in order for the implementation of any alternative to be consistent with the 2010 AOC, changes to the AOC would be required. In addition, DOE would conduct its remediation activities in compliance with other applicable regulations and orders. These include other environmental regulations such as those implementing the Endangered Species Act and the National Historic Preservation Act, safety regulations such as those addressing worker and public safety, and applicable Executive Orders and DOE Orders. S.10.1.2 Process and Criteria Community input has been a major driver in the development of the alternatives for analysis in this EIS, and DOE has provided many opportunities over a number of years for the public to provide input. As discussed in Section S.1, preparation of this EIS began with an Advance NOI (72 FR 58834) in October 2007. Informal discussions with the public and other stakeholders were held, and the resulting information was used in developing the May 16, 2008, NOI (73 FR 28437). The 2008 NOI presented DOE’s proposed alternatives and, in accordance with NEPA regulations, the public was invited to comment on the proposed alternatives or suggest other alternatives or alternative concepts. Preparation of this EIS was delayed to allow EPA to conduct radiological characterization of Area IV and the NBZ; DOE to conduct chemical characterization; and DTSC to develop LUT values identifying the cleanup levels for chemicals and radionuclides. EPA’s radiological characterization effort entailed a historical site assessment of past operations and radiological releases to identify locations for soil sampling; a gamma radiation scan, also to identify areas for soil sampling; collection and radiological analysis of 3,487 soil and 55 sediment samples; and radiological characterization of groundwater and surface water (HGL 2012a).9 DOE’s chemical characterization effort entailed collection and chemical analysis of 5,854 samples and conducting a data gap analysis that reviewed site operations and chemical releases and assessed the adequacy of existing data to guide soil sampling. DTSC published the provisional AOC LUT values for radionuclides in January 2013 and the AOC LUT values for chemicals in June 2013.10 These AOC LUT values are presented in Appendix D, Tables D–2 and D–3. To meet revised regulatory requirements and commitments and to accommodate, to the extent practicable, the preferences of the communities surrounding SSFL and other stakeholders, the alternatives evaluated in this EIS have evolved from those identified in the 2008 NOI (73 FR 28437). As a result, with the exception of a No Action Alternative, the alternatives proposed in 2008 are not among the alternatives evaluated in this EIS. This EIS, however, includes alternatives based on risk and dose for a hypothetical suburban residential scenario, similar to some of the alternatives identified in 2008 that also considered risk, based on future land use scenarios (for example, agricultural, residential, and open space). The alternatives proposed in the 2008 NOI are discussed in Section S.10.1.3, Alternative Concepts Considered but Dismissed from Detailed Study. The 2007 CO (DTSC 2007) originally also applied to soil remediation in Area IV and the NBZ; the 2010 AOC (DTSC 2010a) superseded the 2007 CO for soil remediation. The 2014 SRAM (MWH 2014) supersedes the 2005 SRAM that was cited in the 2007 CO. 9 HydroGeoLogic, Inc., was the EPA contractor for the radiological characterization of Area IV and the NBZ. 10 The radionuclide LUT values are provisional. EPA recommended not selecting final LUT values until a single laboratory is selected to conduct the radionuclide analysis for the cleanup confirmation sampling and the selected laboratory can demonstrate its ability to meet EPA’s defined measurement quality objectives. The chemical AOC LUT values are not provisional because they provide analytical standards for multiple laboratories to report and use when establishing data quality objectives (see Appendix D, Section D.2). 8 S-12 Summary Since initial efforts to prepare this EIS began, DOE has engaged the public about cleanup of Area IV and the NBZ through interviews, workshops, and informational meetings. In spring 2012, DOE sponsored a series of three Community Alternatives Development Workshops in which community members were asked to articulate their preferences for alternatives they would like to see analyzed in this EIS. The workshops resulted in four cleanup concepts that reflect the diverse preferences in the community. Appendix C provides details about the workshop process and the alternative cleanup concepts proposed by the community. Despite the differences in their approaches to cleanup, the four community-developed concepts were similar in their focus on cleaning up and restoring Area IV and the NBZ to a level that allows use of the site as open space for wildlife or human enjoyment, as well as use of “green” and sustainable methods whenever possible to minimize the impact of cleanup on the site and the surrounding communities. All four of the alternative concepts recommended that DOE should take actions to minimize damage to the natural environment during cleanup. DOE has referred to one of the submitted concepts as the Green Cleanup Alternative Concept (see Appendix C). While DOE did not retain this concept as a separate alternative, it designed all of the action alternatives to incorporate green cleanup methodologies. A summary of green cleanup principles adopted by DOE to guide the development of alternatives is included in the following Green Cleanup text box. In addition, community concepts called for minimizing transportation impacts, preferential use of native plants for restoration of the site, and implementation of measures to prevent the spread of invasive, non-native plants. DOE considered all of these community concepts in preparing this EIS; these concepts informed the development of alternatives for this EIS. Green Cleanup DOE is committed to integrating sustainability in its projects consistent with the requirements of Executive Order 13693, Planning for Federal Sustainability in the Next Decade. Impacts on the natural environment would be expected to result from the cleanup of Area IV and the NBZ, regardless of which action alternative is selected. DOE is committed to minimizing impacts by using the principles of “green cleanup.” This approach is consistent with the DOE Office of Environmental Management’s recognition of sustainability as an organizational goal at the highest levels of management (DOE 2015). To the extent practical, green and sustainable remediation and innovative technology practices will be integrated into all phases of remediation. Chapter 7 of this EIS provides additional detail on implementation of greener cleanup principles. For this project, cleanup decisions for all action alternatives would be guided to the extent possible by the EPA Principles for Greener Cleanups (EPA 2009), the ASTM International Standard Guide for Greener Cleanups (ASTM 2013), and DTSC’s Interim Advisory for Green Remediation (DTSC 2009). The purpose of EPA’s principles, ASTM’s standard guide, and DTSC’s Advisory is to improve the decision-making process involved with site cleanup, while assuring the protection of human health and the environment by minimizing the environmental “footprint” of cleanup activities. Principal elements of green sustainable remediation are:      Minimize total energy and maximize use of renewable energy Minimize air pollutants and greenhouse gas emissions Minimize water use and impacts to water resources Reduce, reuse, and recycle materials and waste Protect land and ecosystems S-13 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Many community members who have expressed concerns about transportation, biological, and cultural resources impacts requested that DOE evaluate a risk-based cleanup alternative that might minimize these impacts. In response, in addition to evaluating an alternative for soil cleanup that meets the AOC LUT values, DOE evaluated alternatives that use a risk-based methodology to determine areas and soil volumes that require remediation, based on cleanup to risk levels, similar to concepts considered in the 2008 NOI (73 FR 28437). As input to its 2014 Amended NOI (79 FR 7439), DOE reviewed and evaluated in detail the 2008 scoping comments and concepts developed during the 2012 Community Alternatives Development Workshops. In the Amended NOI, DOE summarized the history of the SSFL Area IV cleanup project, changes in regulatory requirements, and NEPA efforts to that date; presented the 2012 Community Alternatives Development Workshops concepts; announced scoping meetings and its intention to prepare this EIS; and provided the public with further opportunities to provide comments on the scope of this EIS and the alternatives to be evaluated. After receiving stakeholder input from the 2014 scoping comments and the 2012 Community Alternatives Development Workshops, DOE developed screening and balancing criteria to identify alternatives to be evaluated in this EIS. The screening criteria were developed to ensure the proposed alternatives would meet the purpose and need for agency action as described in Section S.2. The balancing criterion included principles for cleanup in a manner that is as environmentally sensitive as possible. Descriptions of the criteria, including their development and selection process, are provided in Appendix C. The main screening criteria selected were:  Regulatory Compliance,  Protect Public and Worker Health and Safety,  Effectiveness, and  Ease of Implementation. The balancing criteria included:  Protect the Environment,  Protect Native American Interests,  Cost,  Community Acceptance,  Return to Natural State,  Minimize Transportation Impacts, and  Preference for Onsite Treatment of Soils. The concepts proposed by members of the community and DOE were first evaluated against the main screening criteria. These criteria were considered the most important criteria in developing the alternatives. The Regulatory Compliance criterion included compliance with applicable requirements of regulations, orders and agreements. The Protect Public and Worker Health and Safety criterion considered the overall safety of the public and workers. The Effectiveness criterion was based on cleanup methods that could be implemented quickly enough to address any short-term risks and provide reliable protection over time. Under the Ease of Implementation criterion, consideration was given to the various components of the proposed concepts and the ease or difficulty with which each could be implemented. If a concept was proposed that was not feasible S-14 Summary or effective because it did not meet the purpose and need (such as some of the soil treatment concepts discussed in Chapter 2, Section 2.2.3), it was eliminated from further consideration in DOE’s NEPA review. Those concepts posing too great a safety risk were eliminated as not being reasonable. Alternative concepts were also screened against regulations, orders, and agreements governing hazardous and radiological materials cleanup and disposal, including the 2007 CO (DTSC 2007) and the 2010 AOC (DTSC 2010a). This screening process resulted in an initial selection of concepts that were then further refined using the balancing criteria and used to build the alternatives for soil remediation, building demolition, and groundwater remediation (see Sections S.10.2 through S.10.4). The balancing criterion, Protect the Environment, included principles for cleanup in a manner that is as environmentally sensitive as possible. This included protecting biological and cultural resources, disturbing or removing as little soil as possible for offsite disposal, incorporating green cleanup principles, and minimizing consumption of resources such as water. Southern California has been under drought conditions for several years, and on April 1, 2015, Governor Brown issued Executive Order B-29-15, which directed the State Water Resources Control Board to impose restrictions that would achieve a statewide 25 percent reduction in potable water usage through February 28, 2016 (CA EO 2015). As a result, Californians reduced their potable urban water use by 24 percent compared to 2013 usage (New York Times 2016). In May 2016, California suspended the mandatory 25 percent reduction and directed local communities to set their own conservation standards (SWRCB 2016). Southern California remains in a severe drought condition. DOE also included a separate Protect Native American Interests criterion. The Santa Ynez Band of Chumash Indians has designated the entire SSFL as a Native American sacred site (referred to herein as the Santa Susana Sacred Site) and believes that the site is eligible for inclusion on the National Register of Historic Places (NRHP) as a traditional cultural property. In 2014, the tribe filed paperwork with the State of California nominating the site to be included in the State of California Native American Heritage Commission Sacred Lands Inventory (NAHC 2014). Executive Order 13007, Indian Sacred Sites, requires Federal agencies that manage Federal lands and activities to “accommodate access to and ceremonial use of Indian sacred sites” and avoid adversely affecting the physical integrity of sacred sites. DOE is consulting with the State Historic Preservation Officer (SHPO), the Santa Ynez Band of Chumash Indians, and the Santa Susana Field Laboratory Sacred Sites Council (SSFL Sacred Sites Council), an organization of Native Americans with historical ties to SSFL land, to develop an agreement intended to resolve adverse impacts through avoidance, minimization, or mitigation of impacts during and subsequent to cleanup activities. The Cost criterion was included to consider the estimated capital, operational, and maintenance costs of implementing each of the alternatives relative to the degree of environmental and human health protection afforded. Cost is often a factor in the decision-making process or in determining whether a proposed alternative is feasible. A cost-benefit analysis of the soil remediation alternatives is included as Appendix J of this EIS. The Community Acceptance criterion was included to consider whether the community would find an alternative acceptable, based on whether there was general public support, general opposition, or a mixture of support and opposition expressed for an alternative concept. The objective of the Return to Natural State criterion was to leave Area IV and the NBZ in as near a natural state as possible to be conducive to their use as open space, parkland, or a wildlife corridor. Notwithstanding this goal, DOE does not own the land and cannot legally determine the ultimate land use. The Minimize Transportation Impacts criterion focused on minimizing, as much as possible, both the onsite and offsite impacts from transporting materials and equipment onto the site for S-15 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory remediation activities and waste and recyclable materials off the site for disposition. Considerations under this criterion included total distance traveled to disposal sites, traffic congestion and safety on local roads and long-haul routes, air emissions, and transfer of non-native or nuisance species onto or off the site. The final balancing criterion, Preference for Onsite Treatment of Soils, was included to give preference to alternatives and treatment methodologies that would treat soil to cleanup standards and leave it on the site rather than remove it for treatment or disposal. S.10.1.3 Alternative Concepts Considered but Dismissed from Detailed Study A number of alternative concepts were proposed by the public during the EIS scoping period in 2008, the Community Alternatives Development Workshops in 2012, and the EIS scoping period in 2014. Not all of these concepts are evaluated in detail as alternatives in this EIS. However, DOE incorporated most of these concepts into the alternatives described in this summary. Table S1 briefly describes the alternative concepts that were considered but dismissed from detailed analysis and the reasons why these concepts were not carried forward as alternatives evaluated in this EIS. More-detailed descriptions of these concepts, as well as a discussion of the analysis undertaken to evaluate each concept and inform DOE’s dismissal of the concept from detailed study, are provided in Chapter 2, Section 2.2.3. S.10.2 Soil Remediation Alternatives This section discusses the four soil remediation alternatives analyzed in this EIS: No Action Alternative, Cleanup to AOC LUT Values Alternative, Cleanup to Revised LUT Values Alternative, and Conservation of Natural Resources Alternative. S.10.2.1 Soil No Action Alternative Under the Soil No Action Alternative, no soil would be treated to reduce constituent concentrations to levels that would meet cleanup criteria or be removed for offsite disposal. Soil would be left in place in perpetuity. Over time, radioactive constituents would continue to decay, and some chemicals would be reduced through natural decomposition processes. Boeing is currently providing site security for the entire SSFL site. If that were to change, then DOE, in accordance with its Atomic Energy Act responsibilities, would provide security at SSFL Area IV and the NBZ. S.10.2.2 Cleanup to AOC Look-Up Table Values Alternative Under this alternative, DOE would remediate soil in Area IV and the NBZ to meet the chemical and radionuclide cleanup LUT values established in accordance with the 2010 AOC. DOE’s planning assumption for cleanup of Area IV and the NBZ is that building removal would be conducted during the first 2 years of the project, followed by soil remediation. Soil removal would be the primary method for cleanup to the AOC LUT values, with onsite treatment (monitored natural attenuation) used where feasible for selected, low-concentration chemicals. Soil would be removed on a systematic basis until all of the soil removal required to meet AOC LUT values is accomplished. Approximately 933,000 cubic yards of soil would be removed and disposed of off site (see Table S–2). Fifteen to 25 workers would be involved with soil removal activities at any one time, not including truck drivers hauling soil off site. Approximately 69,975 truck round trips over 10 years would be required to remove the soil for disposal under this alternative, although additional time could be necessary to allow for partially full trucks and weather delays, as well as to ensure restoration activities and onsite treatment methods are effective. As many as 45,636 truck round trips would be needed to bring backfill to the site (see Table S–5 in Section S.10.2.4). S-16 Summary Table S–1 Matrix of Alternative Concepts Considered but Dismissed from Detailed Study Alternative Concept Cleanup by 2017, consistent with the 2010 AOC or any other action alternative Alternative Description Reason(s) for Dismissal Soil cleanup by 2017 would involve remediation of up to 130 acres and transport of up to 933,000 cubic yards of soil in less than 1 year, resulting in up to 470 daily and 118,200 annual truck trips. Transportation-Related Proposed concepts ranged from minimizing Alternative Concepts the amount of transported soil to evaluating alternative transportation routes and methods. Ultimate Land Use of Area IV after Cleanup Other Soil Cleanup Concepts Cleanup Based on Different Land Use Scenarios No Action (Abandon Area IV) Onsite Containment at SSFL Area IV There is insufficient time to complete regulatory actions (e.g., this EIS and the DOE ROD and the DTSC program EIR and decision) and to load and move the necessary number of trucks from SSFL to complete any action alternative by the 2017 deadline. Some of these concepts (e.g., minimizing the amount of transported soil) were incorporated into the alternatives evaluated in this EIS. DTSC is conducting a transportation study that will be issued in conjunction with its program EIR that evaluates alternative means of transporting debris and soil from SSFL. DOE will evaluate, when available, the study and determine the need for additional NEPA analysis. Potential future land uses include museums DOE does not own the land in Area IV or the NBZ and and parks, a land grant to Native cannot make decisions about its ultimate use. DOE’s Americans, open space, a wildlife corridor, cleanup would be compatible with Boeing’s intended and a wildlife preserve. future land use of undeveloped open space (Boeing 2016a, 2016b). Installation and use of catch basins These concepts raised regulatory or safety concerns: downstream of relatively inaccessible areas - Flushing contaminants from drainages does not meet of the northern drainages that contain DOE’s purpose and need (e.g., is not protective of chemicals or radionuclides exceeding AOC human health and the environment) LUT values to capture water flushed down - The safety risks associated with the use of helicopters drainages (clean water would be introduced or mules in steep terrain are greater than the expected upstream to flush contaminants to the catch benefits. basins, where the then-contaminated water - Dilution through soil mixing is not allowed for would be collected and treated for offsite hazardous waste under RCRA regulations disposal); helicopters/mules for difficult-to(40 CFR 268.3). For nonhazardous soils, this access locations; dilution through soil approach may not be effective in meeting cleanup mixing; and soil compaction into trucks. goals because the concentrations of chemical and radioactive constituents in background soil are not significantly different from those in Area IV and NBZ soils. - Compacting soil in trucks would increase the need for water, present industrial hazards, and add to the timeline to complete the proposed action (e.g., time for loading and unloading each truck). Cleanup based on a range of land uses. The landowner’s (Boeing’s) intended future land use for their portion of SSFL, including Area IV and the NBZ, is undeveloped open space. Consistent with Boeing’s basis for analysis, DOE assumed cleanup levels based on a hypothetical suburban residential land use scenario. a This scenario is more protective than an open land use scenario (Boeing 2016b). Proposed in the 2008 NOI. Cessation of all DOE determined that the No Action Alternative of DOE management and oversight of SSFL continued maintenance is adequate to provide a baseline Area IV. for evaluating the action alternatives. Proposed in the 2008 NOI. Onsite This concept was eliminated because the 2010 AOC containment (which would include burial) does not allow onsite burial or landfilling (excavating and of buildings, wastes, and radiological and burying) of contaminated debris or soil, and it would chemical contaminants, aligned with entail a decision affecting future land use for land that potential future land use scenarios DOE does not own. DOE’s non-AOC alternatives (see including, but not limited to, agricultural, Section S.10.2.3) include leaving in place constituents residential, and open space. determined to meet risk-based standards, but do not include excavating soil and burying it elsewhere in Area IV. S-17 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Alternative Concept Alternative Description Offsite Disposal of SSFL Area IV Materials (cleanup based on agricultural or open space risk assessment scenarios) Proposed in the 2008 NOI. This alternative consisted of demolition of buildings and removal of contaminated media, aligned with potential future land use scenarios including, but not limited to, agricultural, residential, and open space. Nonradiological wastes would be transported to approved disposal or treatment facilities and radiological wastes to approved out-of-state disposal facilities. Reason(s) for Dismissal This concept was partially considered in the development of the alternatives discussed in Sections 2.4.1 and 2.4.2 for soil remediation, in that the Cleanup to Revised LUT Values Alternative addresses soil cleanup based on chemical risk and soil cleanup under the Conservation of Natural Resources Alternative is based on risk for both chemicals and radionuclides (using radiation dose as a surrogate when evaluating radionuclides). To be consistent with the SRAM (MWH 2014), DOE used the hypothetical suburban residential scenario a as the potential future land use. Combination Proposed in the 2008 NOI. Demolition of The onsite disposal portion of this concept was Onsite/Offsite buildings and onsite containment (which eliminated because the 2010 AOC does not allow onsite Disposal Alternative would include burial) of contaminated burial or landfilling (excavating and burying) of for SSFL Area IV media, aligned with potential future land use contaminated debris or soil, and it would entail a scenarios including, but not limited to, decision affecting future land use for land that DOE agricultural, residential, and open space. does not own. DOE’s non-AOC alternatives (see Nonradiological wastes would be Section S.10.2.3) include leaving in place constituents transported to approved disposal or determined to meet risk-based standards, but do not treatment facilities and radiological wastes include excavating soil and burying it elsewhere in to an approved out-of-state disposal facility. Area IV. Alternate Use of Possible use of the ETEC Office Building At this time, none of these concepts is sufficiently Area IV Buildings (Building 4038) as an interpretive center and developed to be considered in this EIS. If any of these the former Sodium Pump Test Facility concepts develop into actual proposals, additional (Buildings 4462 and 4463) for commercial NEPA analysis would be required. purposes. Particle Size Particle size separation: Use size separation Soil treatability studies conducted on Area IV soil Separation/Soil to separate the contaminated size fractions demonstrated that particle size separation was not Washing from the non- or less-contaminated size effective in producing soil fractions that met the AOC fractions (typically sand and larger soil LUT values and, thus, would require additional treatment particles). (Matsumoto and Martin 2015). Soil washing: Place contaminated soil into Soil washing is not considered a viable option because of treatment units (similar to washing the estimated large volume of water and length of time machines) in which mechanical agitation required to complete the effort: approximately 36 years and a washing solution are used to remove and between 80,000 and 160,000 gallons per day of water contaminants from the soil. would be required to treat all 933,000 cubic yards of soil (see Appendix D). Soil washing is normally performed as a volume reduction process to reduce the amount of material being disposed of as hazardous waste, not to remove all of the soil contaminants to background levels. In addition, either an onsite water treatment capability for reuse or offsite disposal of the wash water would be required, and it is uncertain whether soil washing could meet AOC LUT values or other applicable cleanup requirements. Phytoremediation and Use plants and/or soil organisms to remove Studies determined that these processes were ineffective bioremediation or break down contaminants in the soil. in removing or breaking down most of the constituents; however, natural attenuation may be useful for low concentrations of certain hydrocarbons (Nelson et al. 2015b, 2015c). AOC = Administrative Order on Consent for Remedial Action; Boeing = The Boeing Company; CFR = Code of Federal Regulations; DTSC = Department of Toxic Substances Control; EIR = environmental impact report; EIS = environmental impact statement; ETEC = Energy Technology Engineering Center; LUT = Look-Up Table; NBZ = Northern Buffer Zone; NEPA = National Environmental Policy Act; NOI = Notice of Intent; RCRA = Resource Conservation and Recovery Act; ROD = Record of Decision; SRAM = Final Standardized Risk Assessment Methodology Revision 2 Addendum, Santa Susana Field Laboratory, Ventura County, California. a Although Boeing’s intended future land use is undeveloped open space (Boeing 2015b, 2016a, 2016b), the human health impacts analysis in this EIS includes a hypothetical onsite suburban residential scenario that includes the direct exposure pathways of dermal chemical exposure, direct radiation exposure, inhalation of chemical and radioactive constituents, and incidental ingestion of chemical and radioactive constituents (MWH 2014). The hypothetical onsite suburban residential scenario is a more conservative scenario than that of open space; that is, it would yield higher potential human health impacts. Because Boeing has stated that it will restrict future land use and prohibit residential houses and backyard gardens (Boeing 2016b), DOE did not include the indirect garden pathway of ingestion of homegrown fruits and vegetables. S-18 Summary Table S–2 Preliminary Estimated Soil Volumes for Remedial Actions per 2010 AOC Considerations Soil Category Description Estimated volume of soil exceeding the chemical AOC LUT values only (radionuclides below the AOC LUT values) Estimated volume of soil exceeding the chemical AOC LUT values with radionuclides above the AOC LUT values Estimated volume of soil exceeding the radionuclide AOC LUT values only (chemicals below the AOC LUT values) Total volume of soil exceeding the chemical or radionuclide AOC LUT values Volume of soil potentially subject to proposed biological and cultural exemptions per the 2010 AOC Soil Volumes (cubic yards) 1,320,000 88,000 3,000 1,413,000 330,000 Volume of TPH/PAH-contaminated soil potentially subject to natural attenuation 150,000 Total volume of soil potentially subject to removal 933,000 AOC = Administrative Order on Consent for Remedial Action; LUT = Look-Up Table; TPH = total petroleum hydrocarbons; PAH = polycyclic aromatic hydrocarbon. Note: Sums presented in the table may differ from those calculated from table entries due to rounding. Soil treatment studies found evidence that natural attenuation (degradation) of chemicals has been occurring at SSFL since they were first released and predicted that natural processes will continue (Nelson et al. 2015a). DOE therefore concluded that natural attenuation could be effective for management of certain low-concentration, petroleum-contaminated (total petroleum hydrocarbons [TPH] and polycyclic aromatic hydrocarbons [PAHs]) soils. DOE has estimated that implementing onsite treatment in the form of monitored natural attenuation for these hydrocarbons could reduce the amount of soil to be considered for removal from Area IV and the NBZ by 150,000 cubic yards (see Appendix D). Such onsite treatment would have to be approved by DTSC. This onsite treatment was assumed to occur regardless of the soil remediation alternative considered (that is, the 150,000 cubic yards were not included in the total volume of soil considered for removal and offsite disposal under the soil remediation action alternatives). Overview of Soil Remediation DOE would begin soil remediation following completion of building demolition. Figure S–4 shows the extent of the chemical and radioactive constituents above the AOC LUT values in the soil in Area IV and the NBZ. DOE’s remediation responsibilities include the NBZ. However, a portion of the NBZ was impacted by chemicals carried from NASA facilities in Area II; these areas, shown in Figure S–4, would be cleaned up by NASA. Based on analysis of more than 11,000 soil samples, for this EIS DOE has estimated that a volume of 1,413,000 cubic yards of soil does not meet the AOC LUT values (see Table S–2) (see Appendix D).11 The most frequently observed chemical constituents include polychlorinated biphenyls (PCBs), PAHs, TPH, dioxins, and metals (antimony, cadmium, chromium VI, mercury, selenium, and silver) (CDM Smith 2017). The most frequently observed radionuclide constituents are cesium-137 and strontium-90 (HGL 2012a). The estimated volume of soil requiring remediation was adjusted, as described below, to account for proposed exemptions to protect biological and cultural resources and soil with low concentrations of TPH and PAHs that would be treated on site by monitored natural attenuation. DOE estimates the volume of soil that may not meet the AOC LUT values could range from 1,000,000 cubic yards to 2,500,000 cubic yards (see Appendix D). The estimated volume of soil (i.e., 1,413,000 cubic yards) not meeting the AOC LUT values was calculated using a geographic information system evaluation of the vertical and lateral distribution of contamination found during sampling. DOE recognizes that there is uncertainty associated with extrapolating data collected at individual points and, therefore, identified a range of soil volumes. 11 S-19 Figure S–4 Extent of Radiological and Chemical Constituents Above AOC Look-Up Table Values Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory S-20 Summary The 2010 AOC (DTSC 2010a) includes exemptions to protect biological resources, in accordance with the Endangered Species Act, and cultural resources that are eligible for inclusion in the NRHP, in accordance with the National Historic Preservation Act or the California Register of Historical Resources. DOE is currently consulting with the U.S. Fish and Wildlife Service (USFWS) and the California Fish and Wildlife Service (CFWS) regarding biological resources. DOE is also consulting with the California SHPO, the Santa Ynez Band of Chumash Indians, and the SSFL Sacred Sites Council, to support DOE’s determination of the eligibility of cultural resources at SSFL for listing in the NRHP or the California Register of Historical Resources. Locations proposed for protection of biological and cultural resources are identified in this EIS (see Figure S–5). These areas would be protected under any of the soil remediation alternatives. DOE would not take action in any of these areas unless it is demonstrated that levels of chemical or radioactive constituents in the soil pose a risk to human health or the environment, as determined using risk-based screening levels (RBSLs) from the SRAM (MWH 2014). The preliminary estimated volume of soil within areas subject to the proposed biological/cultural exemptions under the 2010 AOC is 330,000 cubic yards (see Appendix D). These areas would be avoided under any of the soil remediation alternatives. Based on soil treatability studies, it appears that natural attenuation will be able to reduce TPH and PAH concentrations adequately to meet the AOC LUT values given sufficient time (due to the low existing concentrations, it would take an estimated 70 years for concentrations to degrade below the AOC LUT values) (CDM Smith 2015b). DOE assumes that DTSC would approve use of natural attenuation processes for low-concentration, petroleum-contaminated (TPH and PAH) soil. The estimated volume of soil at locations with only TPH and PAH contamination is 150,000 cubic yards (see Appendix D). Natural attenuation for this soil was assumed under all soil remediation alternatives. As a result of these adjustments to the soil volume, 933,000 cubic yards of soil exceeding the AOC LUT values is considered in the Cleanup to AOC LUT Values Alternative in this EIS (see Appendix D). Table S–2 summarizes the preliminary estimated soil volumes by 2010 AOC considerations. The 2010 AOC also allows exemptions from soil remediation (up to 5 percent by volume) for unforeseen circumstances. DOE would propose use of these exemptions as necessary to prevent damage in remote locations and avoid areas that are too risky for workers to access. DOE may also propose use of the exemption for soil with constituents that are above the AOC LUT values, are deeper than 5 feet below ground surface, and do not threaten groundwater. Exemptions proposed for these purposes will be described in the forthcoming SRAIPs and were not used in developing the above adjustments to estimated soil volumes analyzed in this EIS. The 2010 AOC (DTSC 2010a) stipulates that soils be cleaned up to LUT values that are local background concentrations or method/minimum detection limits for contaminants for which the method/minimum detection limits exceed background concentrations. Based on the chemical concentrations relative to hazardous waste criteria, risk-based concentrations, and the AOC LUT values, as well as the radionuclide concentrations relative to risk-based concentrations and the AOC LUT values, the following six categories of soil are expected to be removed during remediation efforts: S-21 Figure S–5 Extent of Radiological and Chemical Constituents Above AOC Look-Up Table Values with Proposed Exemption Areas Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory S-22 Summary 1. Soil containing chemical constituent concentrations below both hazardous waste standards and risk-based levels, but above the chemical AOC LUT values, and radionuclides at or below the radiological AOC LUT values. This soil does not meet the definition of hazardous or radioactive waste and would be transported to a permitted California Class II or Class III12 disposal facility, based on the acceptance criteria of the facility. At most sites in the United States, including California, this soil would be left in place (see Appendix D, Section D.3, for comparison with other cleanup projects in California). 2. Soil containing chemical constituent concentrations below hazardous waste standards and above risk-based levels and radionuclide concentrations at or below the radiological AOC LUT values. This soil does not meet the definition of hazardous or radioactive waste and would be transported to a permitted California Class II or Class III disposal facility, based on the acceptance criteria of the facility. 3. Soil containing chemical constituent concentrations exceeding hazardous waste standards and radionuclide concentrations at or below the radiological AOC LUT values. This soil would be transported to a permitted California Class I or out-of-state hazardous waste disposal facility, based on the acceptance criteria of the facility. 4. Soil containing chemical constituent concentrations above the AOC LUT values, but below risk-based levels and hazardous waste standards, and radionuclide concentrations above the radiological AOC LUT values, but below risk-based levels. This soil would be transported to a licensed or authorized low-level radioactive waste (LLW) disposal facility, based on the acceptance criteria of the facility. 5. Soil containing chemical constituent concentrations above risk-based levels that may be a hazardous waste and radionuclide concentrations above the radiological AOC LUT values. This soil would be transported to a facility permitted to receive hazardous waste and licensed or authorized to receive radioactive waste, based on the acceptance criteria of the facility. 6. Soil containing chemical constituent concentrations at or below the AOC LUT values and radionuclide concentrations above risk-based levels. This soil would be transported to a licensed or authorized LLW disposal facility, based on the acceptance criteria of the facility. Table S–3 presents the preliminary estimates of soil volumes based on the soil categories for transportation and disposal considerations. Figure S–5 is a composite map of Area IV and the NBZ showing areas with chemical and radioactive constituents above the AOC LUT values overlain by the proposed exemption areas for sensitive biological and cultural resources, as allowed under the 2010 AOC (DTSC 2010a). The final exemption areas for biological resources will be determined through consultation with USFWS and CFWS as part of the USFWS Biological Opinion. The final exemptions for cultural resources will be determined through consultation with the California SHPO, the Santa Ynez Band of Chumash Indians, and the SSFL Sacred Sites Council. The exemptions are ultimately subject to other agency approval. If levels of constituents in these areas pose a risk to human health and the environment, as determined using RBSLs from the SRAM (MWH 2014), DOE would remove them through carefully planned, focused removals that would result in minimum disturbance. In this EIS, it was assumed that the potential impacts from these focused removals would be a fraction of those associated with the balance of the soil remediation efforts and within the uncertainty associated with the analysis of impacts. Siting and construction requirements for California Class I landfills are similar to those for hazardous waste permitted under Subtitle C of RCRA (e.g., double composite liners and leachate collection systems). Siting and construction requirements for California Class II and Class III landfills are similar to those for nonhazardous waste permitted under Subtitle D of RCRA (e.g., liners and leachate collection systems), except additional requirements exist for Class II landfills compared to those for Class III landfills. 12 S-23 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Table S–3 Preliminary Estimated Soil Volumes for Transportation Soil Category Soil Chemical/Radionuclide Classifications Soil Volumes (cubic yards) 1 Chemicals above AOC LUT values, but below risk-based levels and hazardous waste standards. Radionuclides at or below AOC LUT values. 741,000 2 Chemicals above risk-based levels, but below hazardous waste standards. Radionuclides at or below AOC LUT values. Chemicals above hazardous waste standards. Radionuclides at or below AOC LUT values.a Chemicals above AOC LUT values, but below risk-based levels and hazardous waste standards. Radionuclides above AOC LUT values, but below risk-based levels. 52,000 5 Chemicals above risk-based levels that may be a hazardous waste. Radionuclides above AOC LUT values.a 44,000 6 Chemicals at or below AOC LUT values. Radionuclides above risk-based levels. 3 4 Total 49,000 44,000 3,000 933,000 AOC = Administrative Order on Consent for Remedial Action; LUT = Look-Up Table. a A total of 93,000 cubic yards of soil, with and without radionuclides, is estimated to exceed chemical hazardous waste standards. Note: The total does not equal the sum of the individual entries due to rounding. In accordance with the 2010 AOC, following soil removal, cleanup would be verified by DTSC for chemicals and EPA for radionuclides before backfilling of the excavated areas would start. The verification process would involve collection of confirmatory samples following soil removal, analysis of the samples for constituents of concern, and transmission of the data to the agencies for their review. This verification process could take up to 6 weeks following soil removal. Following confirmation by DTSC and EPA that cleanup standards have been met, excavated areas would be backfilled and graded, slopes would be stabilized, and disturbed areas would be revegetated using native plant species. It was assumed that approximately 75 percent of the soil volume removed would be backfilled to accomplish slope stabilization (see Appendix D). This would require transporting up to 700,000 cubic yards of backfill (if 933,000 cubic yards of soil were removed) to the site. DOE conducted an initial evaluation of three off-SSFL sources of soil for backfill and found none that meets the requirements of the 2010 AOC (that the backfill meets the AOC LUT values) (see Appendix D).13 In addition, DOE has had bags of soil from two home improvement stores analyzed and found that both samples failed to meet the AOC LUT values (see Appendix D). Because the AOC LUT values are very low, finding soil of this purity, especially soil that is comparable to the existing local soil (i.e., that would support the native plant communities), is expected to remain a challenge. If a source of backfill soil that meets all of the AOC LUT values cannot be reasonably found, then DTSC, DOE, and EPA would enter into a consultation process, and DTSC would determine the best available source of backfill (DTSC 2010a). Stormwater discharges from the entire SSFL site are regulated by a site-specific National Pollutant Discharge Elimination System (NPDES) permit and a California Regional Water Quality Control Board, Los Angeles Region, Order issued to Boeing, the landowner (CRWQCB 2007). To maintain compliance, Boeing has implemented a comprehensive, site-wide best management practices (BMP) program that utilizes both structural and nonstructural BMPs (Geosyntec 2012; MWH 2012). The existing NPDES stormwater control and monitoring system would remain in place during soil remediation and restoration. This stormwater control and monitoring system was designed to 13 In support of project implementation, DOE would again search for and evaluate sources of backfill. S-24 Summary provide for the full treatment of runoff from 95 percent of the storms that could occur on site and partial treatment for the remaining 5 percent of the storms (Boeing 2008). DOE would coordinate with Boeing and schedule and perform its soil-disturbing work to minimize the potential to cause perturbations and permit exceedances. DOE would apply a surfactant or soil binder to exposed areas to control dust and deploy wattles (long tubes of inert, usually natural materials such as straw that filter water and retain sediments) to control runoff. Foot and vehicle traffic in exposed areas would be restricted to maintain the surfactant crust. Following concurrence from DTSC and EPA that backfill soil is acceptable, DOE would place the backfill on the excavated areas and re-grade and re-contour as necessary. The area would then be seeded with a native plant seed mixture. DOE would conduct vegetation monitoring per the Revegetation and Habitat Restoration Plan discussed in Chapter 6 of this EIS. Evaluation of Implementation of 2010 AOC Cleanup Requirements This section addresses the technical aspects of implementing the “cleanup to background” approach described in the 2010 AOC (DTSC 2010a) that compelled DOE to look at other soil cleanup alternatives beyond those described in Sections S.10.2.1 and S.10.2.2. In this section, DOE also considers its legal and regulatory responsibilities for considering alternatives for soil cleanup actions. 2010 AOC Soil Cleanup Standards The soil cleanup standards specified in the 2010 AOC are based on “cleanup to background” for soil contaminants. The 2010 AOC stipulated that the soils cleanup standard would be based on LUT values, which are local background concentrations or minimum detection limits for constituents whose minimum detection limits exceed local background concentrations (see Section S.4). The cleanup standard definition applies to chemical as well as radionuclide constituents found in Area IV and the NBZ. DTSC has established AOC LUT values for chemicals and provisional AOC LUT values for radionuclides based on either background concentrations or detection limits (see Appendix D). Background concentrations and minimum detection limits are lower than what is typically used as a standard for soil cleanups. Most cleanups are based on a risk assessment that follows EPA guidance. For example, the risk-based standard (based on the SRAM [MWH 2014]) for mercury is 16.8 parts per million, while the AOC LUT value is 0.13 parts per million. PCBs do not naturally occur, so they do not have a background concentration; therefore, the minimum detection limit is used for the AOC LUT value. For Aroclor 1254, one of the PCBs found in Area IV, the SRAM risk-based standard is 232 parts per billion, and the AOC LUT cleanup standard is 17 parts per billion. For petroleum hydrocarbons, the AOC LUT value is currently set at 5 parts per million; environmental screening levels normally used at other locations in California (SFWQCB 2013) and applicable to other cleanups (EPA 2015b) range from 100 to 500 parts per million. This 1 to 2 orders of magnitude (that is, multiples of 10) difference between what is normally used in soil cleanup and the AOC LUT value occurs for most of the chemicals detected within Area IV and the NBZ.14 For cesium-137, the cleanup standard applied to Area IV soil removal actions (prior to establishment of the provisional radionuclide AOC LUT values per the 2010 AOC) was 9.2 picocuries per gram (Boeing 1999, 2000). The current DOE cleanup standard for cesium-137 in soil using a suburban residential land use scenario (consistent with the SRAM [MWH 2014]) See Appendix D, Table D–3, for a list of AOC LUT values for chemical constituents and the corresponding risk-based standards determined in accordance with the SRAM (MWH 2014). 14 S-25 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory corresponds to a soil concentration of 10.3 picocuries per gram. The provisional AOC LUT value for cesium-137 is 0.225 picocuries per gram.15 The 2010 AOC (DTSC 2010a) confirmation protocol compares every soil sample with the AOC LUT values for 116 chemicals and 16 radionuclides (see Appendix D). Should any chemical or radionuclide exceed its respective AOC LUT value, then the soil must be cleaned up. This EIS refers to this approach as a point-by-point cleanup process. To understand how a point-by-point process would be implemented, DOE reviewed similar cleanup actions at other sites. While there are sites where point-by-point cleanups have been applied, these sites contained only a few chemicals or radionuclides of concern and not the large number of constituents (132) included in the AOC LUTs. DOE reviewed two large remediation projects in California—Hunters Point near San Francisco and McClellan Air Force Base near Sacramento, because they dealt with multiple contaminants. However, both of these cleanups were riskassessment-based (not point-by-point decisions), were focused on about 30 constituents (not 132), and allowed leaving contamination in place. When there are only a few constituents and/or a risk assessment approach is used, a small number of constituents need to meet the established standard. Moreover, the AOC LUT values do not account for the natural occurrence of many constituents in the soil, meaning that they could lead to decisions to remove soil that has not been contaminated by Area IV operations. Therefore, meeting the 2010 AOC LUT values would require an unprecedented approach and effort. High Level of Uncertainty in Cleanup Decisions To be certain that what DOE is cleaning up is contamination resulting from ETEC operations, there must be confidence in the analytical result that the contaminants are actually present and their concentrations exceed the cleanup standard. The 2010 AOC specifies that the detection limits for the chemical AOC LUT values should be based on the “lowest concentrations at which an analyte can be confidently detected in a sample and its concentration can be reported with a reasonable degree of accuracy and precision.” For many of the chemicals (e.g., PCBs) and radionuclides (e.g., strontium-90), however, the AOC LUT values are set at the lower end of the analytical instruments’ abilities to accurately report the presence of the constituent. Exceeding such values does not necessarily indicate that contamination is present because some constituents may be at background levels. As a result, DOE may perform soil cleanup at locations where contamination does not exist. Acceptable Error Rate DTSC has set an acceptable error rate in sample analysis of 5 percent. This means that, for 100 soil samples analyzed for one chemical near the minimum detection limit, five sample analyses could falsely report the chemical’s presence when it is not actually in the sample. A 5 percent error rate may be acceptable when the project involves only one chemical, but, consistent with the 2010 AOC (DTSC 2010a), DOE must consider 116 chemicals and 16 radionuclides. Compounding a 5 percent error rate over 132 different potential constituents in each sample means a much greater chance that DOE would be remediating clean soil, not contaminated soil. Background Data AOC LUT Failures DTSC conducted a soil background study that involved collecting soil samples from two sites approximately 3 to 4 miles west of SSFL (URS 2012).16 DTSC analyzed 148 soil samples for See Appendix D, Table D–2, for a list of provisional AOC LUT values for radioactive constituents. URS Corporation was the DTSC contractor for the chemical characterization of off-SSFL reference areas. The characterization data provide background soil concentrations to which samples collected at SSFL can be compared. 15 16 S-26 Summary 110 different chemicals17 and used this data set for development of the chemical AOC LUT values. Comparing the background soil results with the AOC LUT values, 46 of the 110 chemicals analyzed (42 percent) exceeded their respective AOC LUT values in at least one sample. This implies that, if the point-by-point, chemical-by-chemical process described in the 2010 AOC were applied to the background study locations, they would be declared contaminated and subject to soil remediation. It also demonstrates that it is difficult to differentiate background concentrations from contamination from ETEC operations based on the low AOC LUT values; thus, where to stop soil remediation cannot be clearly defined. Total Petroleum Hydrocarbon AOC LUT Value The AOC LUT value for TPH was set at 5 parts per million without considering its natural presence. The analytical method (EPA Method 8015) is not specific to TPH, but detects any chemical molecule, many of which naturally occur, within the carbon ranges of TPH. Therefore, for any soil sample analyzed for TPH, there is a high level of uncertainty regarding whether the result is actually TPH. In addition, the environmental screening levels normally used at other locations in California (SFWQCB 2013) and applicable to other cleanups (EPA 2015b) range from 100 to 500 parts per million; for this reason, analytical laboratories are not set up to analyze for TPH at 5 parts per million. DOE provided soil samples to two laboratories, and they could not reproduce TPH results below 100 parts per million (Nelson et al. 2015d). California Polytechnic State University, San Luis Obispo, evaluated the types of organic molecules in soil to demonstrate that the results being reported were not TPH. The study demonstrated that there are technical problems with measuring TPH concentrations at such low levels (Nelson et al. 2015d). A review of the TPH data produced for Area IV indicates that as much as 300 parts per million of the reported TPH in any given sample actually results from normally occurring organic materials and are not petroleumrelated (Burgesser 2015). Changes in Site Knowledge Since the Signing of the 2010 AOC When the 2010 AOC (DTSC 2010a) was signed, there was a general belief that there was widespread radioactive contamination in Area IV. However, EPA’s radiological study did not show that Area IV was highly contaminated. EPA concluded, “[a] majority of the Radiological Areas of Interest are congregated within specific areas or are associated with key facilities;” and, “Approximately 70 percent of soil samples with radionuclide concentrations greater than the FALs [field action levels]18 are located within five Area IV Radiological Areas of Interest: RMHF [Radioactive Materials Handling Facility] complex, SRE [Sodium Reactor Experiment] complex, 17th Street Drainage, Former Fuel Element Storage Facility, and New Conservation Yard Drainage” (HGL 2012a). Each of these areas were known to be impacted by radionuclides prior to EPA’s study and had been subject to prior soil removal actions by DOE to an approximate 9.2 picocurie per gram cleanup standard (see, for example, Boeing 1999 and Boeing 2000). Review of data in the Final Radiological Characterization of Soils, Area IV and the Northern Buffer Zone, Area IV Radiological Study, Santa Susana Field Laboratory, Ventura County, California (HGL 2012a) showed that, of the over 3,500 soil samples analyzed by EPA, only about 12 percent of the samples exhibited radionuclide concentrations exceeding EPA’s FALs. Cesium-137 and strontium-90 constituted 94 percent of the reported radionuclides, consistent with site knowledge prior to the EPA study. As a result, the EPA findings disproved the general belief that Area IV is highly contaminated by radionuclides throughout. DTSC also analyzed samples for pH (acidity), but soil pH is not a parameter in the chemical AOC LUT. EPA notes in its final soils report (HGL 2012b) that FALs do not consider EPA’s recommended uncertainty factors, and locations with results exceeding the FALs “do not represent areas of contamination or areas of remediation.” Nonetheless, the FALs were used during site characterization to identify areas of potential radiological contamination. 17 18 S-27 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory What was not clearly known at the time of the signing of the 2010 AOC was the extent of soil contamination by chemicals. The RCRA Facility Investigation (RFI) studies completed during the years 2000 through 2009 focused on chemical contamination associated with Solid Waste Management Units and Areas of Concern (CH2M Hill 2008, 2009; MWH 2006, 2007, 2009). The RFI studies were based on risk assessment standards, and the need to conduct extensive soil sampling away from the investigation areas was not warranted. The AOC LUT values became the basis for soil investigations under the 2010 AOC. DOE concluded that low AOC LUT values, coupled with the false positive issues and the inability to accurately distinguish TPH from a range of other organic molecules (described above), resulted in data showing almost the entirety of Area IV to exceed an AOC LUT value for at least one chemical. In accordance with the 2010 AOC, soil exceeding the AOC LUT for even one chemical would require remediation. As a result, cleanup planning for Area IV and the NBZ was transformed from a mostly radiologically impacted soil cleanup (approximately 91,000 cubic yards) to a mostly chemically impacted soil cleanup (approximately 1,410,000 cubic yards), based on the chemical AOC LUT values (DTSC 2013). 2010 AOC Backfill Soil Requirements Attachment B (Final Agreement in Principle) of the 2010 AOC states the following with regard to use of backfill soil: “Backfill/replacement soils must not exceed local background levels.  Onsite soils that do not exceed local background levels may be used as backfill/replacement soils.  Offsite soils that have been verified to not exceed local background levels may be used as backfill/replacement soils.” Attachment C (Confirmation Protocol “Not to Exceed” Background Cleanup Standard) of the 2010 AOC (DTSC 2010a) states: “Backfill/replacement soils may be from onsite or offsite locations, with a preference for onsite locations. For purposes of this protocol, “onsite” locations are those within the geographic boundaries of the SSFL site).” “For backfill soils obtained from outside the Santa Susana Field Lab, the relevant Look-up Table shall be for the formation to which the backfill soils are to be placed.” There are no onsite borrow sources for DOE’s use at SSFL. Developing onsite borrow sources would significantly add to potential biological impacts at SSFL. In February 2015, DOE conducted an initial evaluation of off-SSFL borrow sites for soil meeting the chemical AOC LUT values.19 The three evaluated sites failed to meet 2010 AOC requirements because multiple chemicals of concern exceeded the AOC LUT values (see Appendix D). In addition, DOE tested packaged soil products sold by home improvement stores. All products tested exceeded the AOC LUT values for multiple chemicals (see Appendix D). Based on this initial evaluation and given the low AOC LUT values, it appears unlikely that replacement soil meeting the AOC requirements can be found. If a soil were found that could meet the AOC LUT values, there is concern that the soil would not be comparable to the physical, chemical, and microbial characteristics of existing soil, making it difficult to reestablish native vegetation in Area IV and the NBZ. In support of project implementation, DOE would again search for and evaluate sources of backfill. If a source of backfill soil that meets all of the AOC LUT values cannot be reasonably found, then DTSC, DOE, and EPA would enter into a consultation process, and DTSC would determine the best available source of backfill (DTSC 2010a). 19 S-28 Summary NEPA Guidance and Regulations for Addressing Alternatives in EIS Documents DOE consulted applicable CEQ and DOE NEPA regulations and guidance in determining reasonable alternatives to the cleanup to AOC LUT values for analysis in this EIS. As noted above, the CEQ NEPA regulations state that an EIS “shall inform [decision-makers] and the public of the reasonable alternatives which would avoid or minimize adverse impacts or enhance the quality of the human environment” (40 CFR 1502.1). In discussing the contents of an EIS, the regulations further indicate the importance of the analysis of alternatives: §1502.14 Alternatives including the proposed action. This section is the heart of the environmental impact statement…. In this section agencies shall: (a) Rigorously explore and objectively evaluate all reasonable alternatives, and for alternatives which were eliminated from detailed study, briefly discuss the reasons for their having been eliminated. (b) Devote substantial treatment to each alternative considered in detail including the proposed action so that reviewers may evaluate their comparative merits. CEQ’s “Forty Most Asked Questions Concerning CEQ’s National Environmental Policy Act Regulations” (CEQ 1981) provides the following guidance:  Range of Alternatives – “The phrase ‘range of alternatives’ refers to the alternatives discussed in environmental documents. It includes all reasonable alternatives, which must be rigorously explored and objectively evaluated. . .”  Alternatives Outside of the Capability of Applicant or Jurisdiction of Agency – “Section 1502.14 [NEPA Regulations 40 CFR Parts 1500 – 1508] requires the EIS to examine all reasonable alternatives to the proposal. In determining the scope of alternatives to be considered, the emphasis is on what is ‘reasonable’ rather than on whether the proponent or applicant likes or is itself capable of carrying out a particular alternative. Reasonable alternatives include those that are practical or feasible from the technical and economic standpoint and using common sense, rather than simply desirable from the standpoint of the applicant.” 2003 Litigation Involving ETEC In addition to the 2010 AOC, this EIS responds to the outcome of a lawsuit filed by the Natural Resources Defense Council, the Committee to Bridge the Gap, and the City of Los Angeles, which successfully challenged DOE’s 2003 ETEC EA (DOE 2003) and Finding of No Significant Impact for remediation of Area IV in the U.S. District Court for the Northern District of California Potential Environmental Consequences of Cleanup to AOC LUT Values As described in Chapter 4 of this EIS, the Cleanup to AOC LUT Values Alternative would result in appreciable resource use and waste generation. Characteristics of this alternative include:      130 acres of land disturbed in Area IV and the NBZ; 933,000 cubic yards of soil removed and 700,000 cubic yards of backfill emplaced, resulting in 116,000 truck round trips (up to 39,000,000 million truck miles); 62,500 round trips of cars or light-duty trucks primarily due to worker commutes; substantial increase in the wear on local roadways; 40 million gallons of water used; S-29 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory   2.8 to 8.2 million gallons of fuel used for trucks and heavy equipment;20 and 28,000 to 84,000 metric tons (total) of greenhouse gases (as carbon dioxide [CO2]) generated.21 Disturbing 130 acres of land in order to remove 933,000 cubic yards of soil would kill plants and animals, destroy portions of their habitats, and require a substantial, focused, and prolonged effort to achieve revegetation and restoration. Habitat could also be affected by incompatible backfill and invasive species brought to SSFL in the 700,000 cubic yards of backfill or on vehicles. In addition, land disturbance would produce fugitive dust that could impact downwind onsite and offsite areas. Transportation for disposal of 933,000 cubic yards of soil would result in 116,000 truck trips (39,000,000 million truck miles) over 10 years and 62,500 round trips of cars or light-duty trucks would result in increases in traffic and noise on local roads. In addition, the increased traffic, in particular the heavy haul trucks, would accelerate road deterioration, requiring repair sooner than currently anticipated. The 40 million gallons of water (used primarily for dust suppression) would further deplete the already stressed Southern California water supply. In addition, the irreversible consumption of 2.8 to 8.2 million gallons of fuel for truck transportation and heavy equipment use would contribute to the generation of a total of 28,000 to 84,000 metric tons of greenhouse gases. S.10.2.3 Additional Soil Remediation Action Alternatives This EIS includes two alternatives in addition to the Soil No Action and Cleanup to AOC LUT Values Alternatives discussed in the previous section. Under the Cleanup to Revised LUT Values Alternative, DOE would continue to apply cleanup criteria on a point-bypoint basis, but would implement revised chemical constituent LUT values for making cleanup decisions (the radionuclide LUT values would be the same as under the Cleanup to AOC LUT Values Alternative). Under the Conservation of Natural Resources Alternative, DOE would apply a traditional riskassessment approach to making cleanup decisions, including using area averaging to determine concentrations and developing risk and dose criteria, as described below. DOE expects that, in order for the implementation of any alternative to be consistent with the 2010 AOC, changes to the AOC would be required. SSFL Area IV EIS Alternatives Soil Remediation Alternatives  No Action  Cleanup to AOC Look-Up Table Values Alternative  Cleanup to Revised Look-Up Table Values Alternative  Conservation of Natural Resources Alternative Building Demolition Alternatives  No Action  Building Removal Alternative Groundwater Remediation Alternatives  No Action  Monitored Natural Attenuation Alternative  Groundwater Treatment Alternative Cleanup to Revised LUT Values Alternative Under this alternative, a revised set of LUT values would be established for chemical constituents, and the LUT values for radioactive constituents would be the same as those under the Cleanup to AOC LUT Values Alternative. The revised chemical LUT values would be based on RBSLs. The This large range results from the analysis considering disposal in facilities near SSFL, as well as in facilities long distances from SSFL (for example, a hazardous waste disposal facility in Idaho). 21 See footnote above. 20 S-30 Summary RBSLs would be calculated for the direct pathways22 of the hypothetical suburban residential land use scenario established for SSFL (MWH 2014), in which it is assumed that a receptor would be present on the remediated site 24 hours per day, 350 days per year, for 30 years. The revised LUT values for chemical constituents would be concentrations that correspond to a 1 × 10-6 (1 chance in 1 million) risk of developing a cancer and/or a toxicity hazard quotient23 of 1. Soil would first be removed in the SRE and RMHF areas, where hazardous chemicals and radioactive constituents above the revised LUT values are most prevalent. Remediation would then expand outward from those areas to remove the remaining soil with chemical and/or radioactive constituents present above revised LUT values. As under the Cleanup to AOC LUT Values Alternative, cleanup decisions would be made on a point-by-point basis. That is, if the soil in a particular area exceeded the revised LUT value for any chemical or radioactive constituent, the soil would be removed. Approximately 192,000 cubic yards of soil would be removed under this alternative. Figure S–6 shows the total extent of chemical and radioactive constituents above the revised LUT values and those areas from which soil would be removed. Approximately 14,400 truck round trips over a little more than 2 years would be required to remove the soil for disposal under this alternative, although additional time could be necessary to allow for partially full trucks and weather delays, as well as to ensure restoration activities are effective. Approximately 9,400 truck round trips (rounded value) would be needed to bring 144,000 cubic yards of backfill to the site. Some, but not all, of the issues associated with implementing the Cleanup to AOC LUT Values Alternative would also affect the Cleanup to Revised LUT Values Alternative. Like the Cleanup to AOC LUT Values Alternative, this alternative would require point-by-point decisions on individual constituents. However, each sample would have to meet the revised LUT values for 34 constituents (18 chemicals that exceed risk-based screening levels from the SRAM [MWH 2014] and 16 radionuclides). If any one of the constituents were to exceed its respective revised LUT value, DOE would make a decision to remediate the area represented by the sample. Although fewer constituents would need to be evaluated under the Cleanup to Revised LUT Values Alternative, the point-by-point cleanup decisions would be subject to issues similar to those under the Cleanup to AOC LUT Values Alternative. Specifically, if any one constituent fails to meet its revised LUT value, a cleanup decision would be required. Although the decision thresholds would be higher, the potential for false positives introduces uncertainty in determining whether a detection actually represents contamination from ETEC operations (see Section S.10.2.2). Under this alternative, a smaller volume of backfill would be needed (144,000 cubic yards), and the chemical LUT values applicable to the backfill would be less restrictive than those under the Cleanup to AOC LUT Values Alternative. As with the Cleanup to AOC LUT Values Alternative, finding a source of backfill that has the physical, chemical, and microbial characteristics that would support establishment of native vegetation may be a challenge. A search for such soil would be conducted in support of project implementation. Direct exposure pathways include inhalation, incidental ingestion, and dermal contact with the chemicals in the soil. The indirect pathway of a garden from which the hypothetical suburban resident derives all of his or her fruits and vegetables is not included in the analysis in this EIS. 23 Hazard index is the sum of hazard quotients of noncarcinogenic chemicals. A hazard index below 1.0 will likely not result in adverse noncancer health effects over a lifetime of exposure. A hazard quotient is a unitless value determined by: (1) dividing the exposure concentration by the EPA reference concentration for inhalation exposures, or (2) dividing the average daily dose by the EPA reference dose for oral exposures. The reference concentration (for inhalation) or reference dose (for ingestion) (reported in EPA’s Integrated Risk Information System [EPA 2015a]) is an estimate of a continuous exposure of the human population (including sensitive subgroups) that will likely not result in adverse health over a lifetime of exposure. 22 S-31 Figure S–6 Soil Remediation – Cleanup to Revised LUT Values Alternative with Proposed Exemption Areas Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory S-32 Summary Conservation of Natural Resources Alternative Under this alternative, DOE would remediate Area IV and the NBZ to reduce the concentrations of chemical and radioactive constituents in the soil to levels necessary to protect human health. This alternative reduces risk to the public and the environment, yet conserves natural resources, including biological, cultural, and water resources. The hypothetical onsite suburban residential exposure scenario (using the direct pathways) as identified in the SRAM (MWH 2014) was selected as the basis for the risk assessment. Cleanup would be targeted at locations posing risk based on the outcome of a risk assessment and dose analysis. Area IV and the NBZ would be subdivided into smaller areas or units for which concentrations would be averaged for purposes of evaluating risk or radiation exposure. For each unit, risk assessment calculations would be performed individually for each chemical, and then the results summed to determine the risk value. The risk results for each unit would be compared with the risk limit of 1 × 10-6 (1 chance in 1 million) for cancer-causing chemicals and/or to a hazard index of 1 for noncarcinogenic chemicals to make decisions regarding cleanup of the contaminated soil. DOE would cleanup chemicals in accordance with applicable requirements. For each unit, a dose assessment would also be performed to determine the level of radionuclide cleanup needed. Cleanup would be performed to levels as low as reasonably achievable (ALARA)24 below the DOE standard of 25 millirem per year (DOE Order 458.1) to the hypothetical suburban resident. In applying the ALARA principle to soil remediation, DOE would clean up soil to limit public and worker radiation exposures to the lowest levels practical commensurate with sound economic and social considerations (DOE 2014b). Soil would be cleaned up to reduce potential doses to a hypothetical member of the public to below 25 millirem per year, with the specific level determined through the ALARA analysis. The DOE standard of 25 millirem per year serves as an upper limit to the range of doses that may be acceptable and is evaluated as a starting place for ALARA analysis. If this alternative is chosen, DOE would evaluate different cleanup options (that is, levels corresponding to doses below 25 millirem per year) to determine whether additional cleanup would provide the optimal balance of the benefits from exposure reduction (e.g., health protection, regulator and public goodwill) with the costs (e.g., economic, schedule, social), considering doses that may be received by hypothetical members of the public and by workers performing cleanup. If the ALARA analysis resulted in implementation of a cleanup level less than 25 millirem per year, some or all of the additional 44,000 cubic yards of soil containing radionuclides above the AOC LUT values would be remediated (see soil volumes on Table S–4 in Section S.10.2.4). The potential impacts of removing additional soil would fall between those presented for this alternative and those for the Cleanup to Revised LUT Values Alternative. Cleanup based on risk assessments for individual units accounts for the receptor’s exposure to an average concentration in the unit in contrast to the point-by-point evaluation of the Cleanup to AOC LUT Values Alternative and the Cleanup to Revised LUT Values Alternative, where each sample must meet the LUT values for each constituent. ALARA is based on the system of dose limitation recommended in International Commission on Radiological Protection (ICRP) Publication 26: “all exposures shall be kept as low as reasonably achievable, economic and social factors taken into account” (ICRP 1977). In ICRP Publication 37 (ICRP 1983), this component was referred to as “the optimization of radiation protection.” ALARA is an approach to radiation protection to manage and control releases of radioactive material to the environment and exposure to members of the public and the work force so that levels are as low as reasonable, taking into account societal, environmental, technical, economic, and public policy considerations. As used in DOE Order 458.1, Radiation Protection of the Public and the Environment (DOE 2011a), ALARA is not a specific release or dose limit, but a process whose goal is to optimize control and management of releases of radioactive material to the environment and doses so that they are as far below the applicable limits of the order as reasonably achievable. 24 S-33 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory This alternative would result in the least amount of ground disturbance and soil that would be removed for offsite disposal: 148,000 cubic yards (see Table S–4 in Section S.10.2.4). The volume of soil containing chemicals above risk-based levels that would be removed would be approximately the same as that under the Cleanup to Revised LUT Values Alternative (approximately 145,000 cubic yards), as would the volume of soil removed that only exceeds risk-based levels for radionuclides (3,000 cubic yards). This alternative would avoid the excavation and offsite transport of soil with concentrations that are less than risk-based levels. Figure S–7 shows the extent of soil removal that would be required under this alternative. As shown in Table S–5 (see Section S.10.2.4), approximately 11,100 truck round trips over 2 years would be required to remove the soil for disposal under this alternative, although additional time could be necessary to allow for partially full trucks and weather delays as well as to ensure restoration activities are effective. As many as 7,200 truck round trips (rounded value) would be needed to bring 111,000 cubic yards of backfill to the site. Implementation of the Conservation of Natural Resources Alternative would entail different issues than implementation of either the Cleanup to AOC LUT Values Alternative or Cleanup to Revised LUT Values Alternative. DOE would divide Area IV and the NBZ into risk assessment units and evaluate those units against risk and dose criteria. An assessment of each area would be required to determine the relative quantities of chemicals and/or radionuclides that would trigger a cleanup decision. Rather than a single number for a given constituent across the entire Area IV and NBZ, the value that would result in cleanup has to be considered in concert with other constituents in an area to determine whether soil meets the cleanup targets (i.e., a chemical risk of 1 × 10-6 [a lifetime chance of 1 in 1 million of developing a cancer], a hazard index of 1 [the level below which no toxic effects would be expected], and an annual dose of 25 millirem [plus ALARA]). The approach of averaging the concentrations of constituents across assessment units has the potential of leaving localized areas of contamination that would be removed under a point-by-point cleanup like the Cleanup to AOC LUT Values Alternative or Cleanup to Revised LUT Values Alternative. Although a smaller volume of backfill would be required (111,000 cubic yards), and the allowable concentrations of chemical and radionuclides would be less restrictive than those for the Cleanup to AOC LUT Values Alternative and similar to those for the Cleanup to Revised LUT Values Alternative, finding a backfill source that has the physical, chemical, and microbial characteristics that would support establishment of native vegetation may be a challenge. A search for such soil would be conducted in support of project implementation. S.10.2.4 Summary of Soil Remediation Alternatives It is DOE’s policy that work be conducted safely and efficiently and in a manner that ensures protection of workers, the public, and the environment. To achieve this policy for SSFL remediation, effective safety requirements and goals would be established through the adoption of applicable national and international consensus standards and where necessary to address unique conditions, through development and implementation of additional standards. DOE would implement Integrated Safety Management in accordance with DOE directives and include related requirements in remediation contractor contracts. DOE’s ultimate goal is zero accidents, work-related injuries and illnesses, regulatory violations, and reportable environmental releases. DOE would ensure that for all activities and phases in the remediation of SSFL, appropriate mechanisms are in place to ensure that exposures to workers, the public, and the environment to radiological and nonradiological hazards are maintained below regulatory limits. Furthermore, DOE would ensure that deliberate efforts are taken to keep exposures to radiation ALARA, consistent with DOE Order 458.1 and 10 CFR 835. S-34 Figure S–7 Soil Remediation – Conservation of Natural Resources Alternative with Proposed Exemption Areas Summary S-35 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory As described in the preceding sections, DOE evaluated the No Action Alternative and three action alternatives for soil cleanup within Area IV and the NBZ. Under each of the action alternatives, DOE assumes that DTSC will approve the use of monitored natural attenuation for the onsite treatment of 150,000 cubic yards of soil containing low levels of TPH and PAHs.  No Action Alternative – DOE would continue monitoring and maintenance activities and ensure that site security is maintained. There would be no treatment of soil to reduce constituent concentrations or removal of soil for disposal off site. Soil would be left in place in perpetuity.  Cleanup to AOC LUT Values Alternative – DOE would start at one side of the site and proceed across Area IV and the NBZ, removing soil exceeding the AOC LUT values, based on a point-by-point determination. An estimated 933,000 cubic yards of soil would be removed from the site over a 10-year time frame. The number of truck round trips (rounded values) would be about 70,000 for removing soil from the site and 46,000 for transporting backfill to the site.  Cleanup to Revised LUT Values Alternative – DOE would remove soil exceeding the revised LUT values. Chemical cleanup levels would be based on the direct exposure pathways for the hypothetical onsite suburban residential scenario, as outlined in the SRAM (MWH 2014). Levels would be based on a cancer incidence risk of 1 chance in 1 million and a hazard quotient of 1. The radionuclide LUT values would be the same as those for the Cleanup to AOC LUT Values Alternative. DOE would remove all soil in Area IV and the NBZ exceeding the revised LUT values. As with the prior alternative, DOE would make soil remediation decisions on a point-by-point basis. An estimated 192,000 cubic yards of soil would be removed from the site over a little more than 2-year time frame. The number of truck round trips (rounded values) would be about 14,400 for removing soil from the site and 9,400 for transporting backfill to the site.  Conservation of Natural Resources Alternative – DOE would clean up soil to a level that would protect human health by removing soil with concentrations of chemical or radioactive constituents that exceed criteria established using a risk assessment process. This alternative would reduce risk to the public and the environment, yet conserve natural resources by disturbing less land than the other alternatives, thereby reducing the potential of impacting visual, biological, cultural, and water resources. Cleanup levels would be based on a hypothetical onsite suburban residential scenario, as outlined in the SRAM (MWH 2014), and averaging the concentrations over a risk assessment area or unit. Chemically impacted soil would be removed to achieve a cancer incidence risk of 1 chance in 1 million and a hazard index of 1; radiologically impacted soil would be removed to ALARA levels below the dose rate of 25 millirem per year. An estimated 148,000 cubic yards of soil would be removed from the site within a 2-year time frame. The number of truck round trips (rounded values) would be about 11,100 for removing soil from the site and 7,200 for transporting backfill to the site. Each of the action alternatives would require approximately 4.0 million gallons of water each year for dust suppression during soil excavation and loading of trucks. Although the annual need is within the Calleguas Municipal Water District’s (CMWD) current capacity, water use is an important consideration in the comparison of soil remediation alternatives, given the current drought conditions in the State of California and Governor Brown’s Executive Order requiring a statewide 25 percent reduction in potable water use (CA EO 2015). Similarly, regardless of the action alternative that DOE may select, transportation of material to and from SSFL is a key issue. Each of the action alternatives would include transportation of large S-36 Summary quantities of building debris and soil to offsite disposal facilities. Whereas there are major highways north and south of SSFL, access to and from those highways requires travel on local roadways through commercial and residential areas. The section of roadway nearest SSFL over which all traffic to and from SSFL would pass is a 2.5-mile-long, two-lane road (Woolsey Canyon Road). Woolsey Canyon Road25 would be used by all large vehicles and most personal vehicles accessing SSFL in support of DOE, NASA, and Boeing as each is responsible for implementing its respective SSFL remediation activities. Contaminated soil and building demolition debris would be transported off site for disposal in haul trucks with a 23-ton payload or in containers placed on trucks with a 20-ton payload. Trucks would be covered or other appropriate methods would be used to minimize dust and contain the contents while in transit to disposal destinations. DOE would consider use of alternative-energy-fueled vehicles, if available and practicable, to minimize transportation impacts. DOE, NASA, and Boeing, have responsibility for cleaning up their respective portions of SSFL and may do so simultaneously until each has completed its effort. Because of the large number of trucks that would be required and concern regarding how many trucks could reasonably and safely be accommodated on the main access road to SSFL, DOE, NASA, and Boeing have entered into an agreement that establishes the total number of truck round trips that would be allowed daily and how those trips would be apportioned among them (Boeing 2015a). The agreement allows a maximum of 96 truck round trips at SSFL each workday (Monday through Friday), equally divided among the entities engaged in cleanup activities. The number of trucks that would transport materials each day would depend on a number of factors: the building demolition rate, the soil excavation rate, and the truck staging and loading rate; the distance to the disposal sites; the availability of trucks; and project funding. Under the agreement, as the number of entities involved in cleanup decreases, the number of truck round trips available to the remaining entities would increase. In this EIS, DOE assumes that it would be allotted 32 truck round trips daily for the first two years of the project and an average of 48 round trips daily thereafter. Even if DOE were allotted as many as 96 round trips daily, the average rate would be 48 round trips, with occasional surges to accommodate periods of higher activity (e.g., to expedite cleanup). Table S–4 provides the soil volumes that would be removed under each action alternative. As shown in Table S–4, within the accuracy of the estimates of soil volume and weight, the same quantities of soil in Categories 2, 3, 5, and 6 would be remediated under all of the action alternatives. Under the Cleanup to Revised LUT Values Alternative, soil in Category 4 (soil with radionuclide concentrations above AOC LUT values that would not cause a dose in excess of 25 millirem per year via the direct exposure pathways for the hypothetical onsite suburban residential scenario) would also be removed. Under the Cleanup to AOC LUT Values Alternative, in addition to the Category 4 soil, Category 1 soil (soil that does not meet the definition of either hazardous or radioactive waste and does not contain chemical constituents that exceed risk-based levels, contains chemical constituents above the AOC LUT values) would be removed. Table S–5 shows the number and timing of the truck round trips that would be required to transport the soil for disposal and backfill for site restoration. Costs of the alternatives correlate to the quantity of soil removed; that is, the larger the quantity of soil removed, the higher the costs. Although there would be some reduction in the risk remaining following remediation with each increment of soil removed, proceeding from the alternative with the least soil removed (Conservation of Natural Resources Alternative) to that with the most soil removed (Cleanup to AOC LUT Values Alternative), the Woolsey Canyon Road is the only serviceable road for heavy truck traffic to and from SSFL. The pavement on Woolsey Canyon Road shows few signs of structural failure, but is showing signs of age and brittleness, indicating that the pavement is near the end of its useful life. Portions of the roadway have recently been repaired. 25 S-37 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory largest reduction in risk would occur between the No Action and Conservation of Natural Resources Alternatives. A smaller reduction in risk would be realized between the Conservation of Natural Resources and Cleanup to Revised LUT Values Alternatives. Even though the largest increment of soil would be removed between the Cleanup to Revised LUT Values and Cleanup to AOC LUT Values Alternatives, there would be minimal change in the risk remaining following cleanup. (See the text box, Comparison of Risk Management and Cost Among Soil Remediation Alternatives.) Under all action alternatives, the amount of soil removed and the areal extent of the cleanup would incorporate the proposed 2010 AOC (DTSC 2010a) exemption areas for sensitive biological and cultural resources per USFWS, CFWS, SHPO, Santa Ynez Band of Chumash Indians, and SSFL Sacred Sites Council consultation (see Figures S–5, S–6, and S–7). DOE would use exemptions provided in the 2010 AOC that are approved by DTSC and would not take action in any of these areas unless it is demonstrated that levels of constituents in the soil pose a risk to human health or the environment (as determined using RBSLs from the SRAM [MWH 2014]) and soil removal is necessary. DOE would implement these exemptions on a case-by-case basis in consultation with DTSC, only remove the quantity of soil necessary to reduce the risk, and take all precautions to protect the environment as part of the action. Comparison of Risk Management and Cost Among Soil Remediation Alternatives Appendix J of this EIS presents an analysis of the costs and benefits of the soil remediation alternatives. The costs are presented in terms of present worth, that is, the cost in current dollars, taking into account the duration of the alternative and the future value of money. The benefits are presented as risks to human health as measured by the risk of cancer or the hazard index (for non-cancer-causing chemicals) remaining after implementation of an alternative. The analysis is based on evaluation of four locations; the representative locations were selected because they were identified by EPA as having radionuclide contamination, had been subject to prior cleanup actions, and provided a range of chemical constituents characteristic of Area IV operations. The range of risk in these four exposure areas is expected to represent the upper boundary across Area IV and the NBZ for cancer risk and for noncancer hazard. Results of these analyses as applied to Area IV and the NBZ are summarized below. As shown below, the cancer risks and toxic hazards (as indicated by the hazard index) decrease across the alternatives from the highest level (under the No Action Alternative) to the lowest level (under the Cleanup to AOC LUT Values Alternative). Conversely, the costs increase across the alternatives in reverse order, with the lowest cost under the No Action Alternative and the highest cost under the Cleanup to AOC LUT Values Alternative. Note: S-38 No Action Alternative Cost: $3 million Cancer risk: 6.3 × 10-5 to 3.5 × 10-4 or 1 chance in 3,000 to 16,000 Hazard index: 0.8 to 30 Conservation of Natural Resources Alternative Cost: $124 million Cancer risk: 1.1 × 10-5 to 4.0 × 10-5 or 1 chance in 25,000 to 91,000 Hazard index: 0.6 to 1 Cleanup to Revised LUT Values Alternative Cost: $168 million Cancer risk: 3.7 × 10-6 to 9.8 × 10-6 or 1 chance in 100,000 to 270,000 Hazard index: 0.04 to 0.5 Cleanup to AOC LUT Values Alternative Cost: $468 million Cancer risk: 3.2 × 10-6 to 9.6 × 10-6 or 1 chance in 100,000 to 310,000 Hazard index: 0.02 to 0.4 Consistent with normal practices at this stage of project development, rough order of magnitude costs for implementing the alternatives were estimated. Actual costs would be expected to fall within a range from 20 percent less to 40 percent more than the rough order of magnitude estimate. Table S–4 Remediation Soil Quantities and Truck Traffic by Alternative Cleanup to AOC LUT Values Alternative Soil Category 1 Chemicals above AOC LUT values, but below risk-based levels and hazardous waste standards. Radionuclides at or below AOC LUT values. Cleanup to Revised LUT Values Alternative Conservation of Natural Resources Alternative 741,000 cubic yards 1,112,000 tons 55,600 truckloads 52,000 cubic yards 78,000 tons 3,900 truckloads 52,000 cubic yards 78,000 tons 3,900 truckloads 52,000 cubic yards 78,000 tons 3,900 truckloads Soil Category 3 49,000 cubic yards 73,500 tons 3,700 truckloads 49,000 cubic yards 73,500 tons 3,700 truckloads 49,000 cubic yards 73,500 tons 3,700 truckloads Soil Category 4 44,000 cubic yards 66,000 tons 3,300 truckloads 44,000 cubic yards 66,000 tons 3,300 truckloads Soil Category 5 44,000 cubic yards 66,000 tons 3,300 truckloads 44,000 cubic yards 66,000 tons 3,300 truckloads 44,000 cubic yards 66,000 tons 3,300 truckloads Soil Category 6 3,000 cubic yards 4,500 tons 230 truckloads 3,000 cubic yards 4,500 tons 230 truckloads 3,000 cubic yards 4,500 tons 230 truckloads Chemicals above risk-based levels, but below hazardous standards. Radionuclides at or below AOC LUT values. Chemicals above hazardous waste standards. Radionuclides at or below AOC LUT values. Chemicals above AOC LUT values, but below risk-based levels and hazardous waste standards. Radionuclides above AOC LUT values, but below risk-based levels. Chemicals above risk-based levels and may be a hazardous waste. Radionuclides above AOC LUT values. Chemicals at or below AOC LUT values. Radionuclides above risk-based levels. Area Affected 130 acres Total Volume 933,000 cubic yards Total Weight Total Truck Round Trips 1,399,500 tons a 70,000 truckloads 40 acres 32 acres 192,000 cubic yards 148,000 cubic yards 288,000 tons 222,000 tons 14,400 truckloads 11,100 truckloads AOC = Administrative Order on Consent for Remedial Action; LUT = Look-Up Table. a Truck round trips were conservatively estimated based on transporting 20 tons of containerized waste per truck. If 23-ton trucks were used for nonradioactive waste, truck trips would be reduced by 11 percent under the Cleanup to AOC LUT Values Alternative and the Cleanup to Revised LUT Values Alternative, and 9 percent under the Conservation of Natural Resources Alternative. Notes: – Sums and products may not equal those calculated from table entries due to rounding. – Cubic yards are converted to tons using a conversion factor of 1.5 tons per cubic yard (see Appendix D). Summary Soil Category 2 S-39 S-40 Table S–5 DOE Truck Round Trips by Year for Remediation Alternativesa Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 Year 7 Year 8 Year 9 Year 10 Year 11 Year 12 Totals Soil Remediation Alternatives Cleanup to AOC LUT Values Alternative Radionuclides above background concentrations; with and without chemicals above AOC LUT values (LLW and MLLW). 0 0 695 708 708 708 708 708 708 708 708 463 6,825 Chemicals exceeding AOC LUT values; includes hazardous wastes. 0 0 6,433 6,554 6,554 6,554 6,554 6,554 6,554 6,554 6,554 4283 63,150 Backfill soil 0 0 4,649 4,736 4,736 4,736 4,736 4,736 4,736 4,736 4,736 3,097 45,636 Totals 0 0 11,778 11,999 11,999 11,999 11,999 11,999 11,999 11,999 11,999 7,841 115,611 Cleanup to Revised LUT Values Alternative Radionuclides above background concentrations; with and without chemicals above Revised LUT values (LLW and MLLW). 0 0 3,413 3,412 Chemicals exceeding Revised LUT values; includes hazardous wastes. 0 0 3,716 3,851 9 7,575 Backfill soil 0 0 4,649 4,736 5 9,391 Totals 0 0 11,778 11,999 14 23,791 6,825 Conservation of Natural Resources Alternative Radionuclides above background concentrations; includes chemically contaminated soil. 0 0 3,413 112 3,525 Chemicals exceeding risk assessment levels; includes hazardous waste. 0 0 3,716 3,859 7,575 Backfill soil 0 0 4,649 2,590 7,239 Totals 0 0 11,778 6,561 18,339 750 750 Building Removal Alternative Building removal 1,500 Backfill soil 63 815 878 Totals 813 1,565 2,378 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Number of Truck Round Trips per Year Number of Truck Round Trips per Year Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 Year 7 Year 8 Year 9 Year 10 Year 11 Year 12 Totals 1 1 1 1 1 17 Groundwater Remediation Alternatives Groundwater Monitored Natural Attenuation Alternative Well installation and monitoring 1 1 1 1 1 1 6 Sr-90 Source Removal – Bedrock 0 0 128 b Backfill soil 0 0 83 83 Totals 0 0 211 211 Groundwater Treatment Alternative 128 - Annual truck round trips are rounded values. As a consequence, sums presented in the table may differ from those calculated from table entries. - Blanks indicate no heavy-duty truck transport activity would occur in the year. Summary AOC = Administrative Order on Consent for Remedial Action; LLW = low-level radioactive waste; LUT = Look-Up Table; MLLW = mixed low-level radioactive waste; Sr = strontium. a This table shows round trips for heavy-duty trucks hauling waste from the site and backfill to the site. A few additional heavy-duty truck shipments would also be required for delivery of equipment, and light- and medium-duty truck shipments would be required for supplies, sample delivery, groundwater treatment medium exchange, and similar activities. Those miscellaneous shipments are not reflected in this table, but have been accounted for in the analysis. Trucks would operate 250 days per year in accordance with the agreement with NASA and Boeing (Boeing 2015a). Backfill soil round trips would go from the backfill source to Area IV and return for additional backfill. Soil removal trucks would go from Area IV to the disposal facility or an intermodal facility, where the soil containers would be loaded on a train; the trucks would then return to Area IV for an additional soil removal load. DOE’s cleanup schedule is based on an average of up to 32 truck round trips per workday for the first 2 years, then 48 truck round trips per workday for the remainder of the project. b In-ground volume of solid rock would be approximately 1,050 cubic yards; the removed rock is assumed to have an expanded volume of 1,700 cubic yards (see Appendix D). Using a conversion of 1.5 tons per cubic yard and 20 tons per truck would result in 128 truckloads for strontium-90 source removal from the bedrock. Notes: S-41 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory S.10.3 Building Demolition Alternatives S.10.3.1 Background A total of 22 structures remain in Area IV; 18 are owned by DOE and 4 by Boeing, as shown in Figure S–8. In this EIS, DOE is evaluating disposition of its 18 structures in Area IV. DOE has never had buildings in the NBZ. Seven of the 18 DOE structures are metal sheds used for material storage; the other 11 are more-substantial structures, consisting of prefabricated metal buildings constructed on grade-level, concrete platforms; buildings with formed concrete basements; and buildings with cinder block/concrete walls and metal roofs. The more substantial structures are the Sodium Pump Test Facility (Buildings 4462 and 4463), ETEC Office Building (Building 4038), Building 4057 Warehouse, Hazardous Waste Management Facility (Buildings 4029 and 4133), RMHF (Buildings 4021, 4022, and 4034), and former reactor complex buildings (Buildings 4019 and 4024). The seven metal sheds are part of the RMHF (Buildings 4044, 4075, 4563, 4621, 4658, 4665, and 4688). The Hazardous Waste Management Facility no longer manages hazardous waste and RMHF no longer manages radioactive waste. The Building 4057 Warehouse is used for field equipment storage, but the remaining buildings are unoccupied and unused. In addition to the structures, the associated parking lots are included as part of the building demolition activity. Two alternatives are being evaluated for building demolition: the No Action Alternative and the Building Removal Alternative. S.10.3.2 Building No Action Alternative Under the Building No Action Alternative, the 18 DOE-owned structures in Area IV would remain in place. DOE would conduct surveillance and maintenance as needed for safety (e.g., preventing access). Because radiological materials would remain in some buildings, DOE would continue its responsibilities in accordance with the Atomic Energy Act and ensure continuation of security that restricts access to Area IV and the structures. S.10.3.3 Building Removal Alternative Under this alternative, DOE would demolish the 18 structures it owns in Area IV and dispose of or recycle the materials off site. Building demolition would start following the DOE ROD for this EIS and a decision following completion of the DTSC program environmental impact report (EIR) prepared under the California Environmental Quality Act (CEQA)26 and would take approximately 2 years to complete, contingent on funding. Building removal activities are estimated to disturb about 8.4 acres. Approximately 1,500 truck round trips would be required to haul the DOE building demolition debris from Area IV for either disposal or recycle (see Table S–5). Building demolition plans would be prepared for each structure by DOE’s demolition contractor to ensure worker safety is maintained throughout the demolition process and regulatory requirements and DOE guidelines are met for each facility. These plans would include identifying potential hazards for each structure (such as the presence of radiological or chemical materials or building structural issues) and specifying protective equipment and procedures to protect workers from specific hazards. DTSC is preparing a program EIR for the entire SSFL (Areas I through IV, the NBZ, and the Southern Buffer Zone). The program EIR will evaluate remediation activities of DOE, NASA, and Boeing. The draft program EIR is currently in preparation. 26 S-42 Summary Figure S–8 Remaining Structures in Area IV At least two staging areas would be established to support building demolition and soil remediation work. The first would be the main staging area within the north-central portion of Area IV, near Building 4024. This staging area may be supplemented by an additional area south of Building 4038 (see Figure S–8) that would include a contractor trailer, worker parking, portable restrooms, heavy equipment parking, and a decontamination pad. As necessary, temporary RCRA storage areas would be established to store wastes while awaiting shipment off site for disposal. The storage areas would consist of areas approximately 20 feet square, with berms around the perimeter and liners to capture any potential spills. In preparation for demolition activities, surveys of building structural materials for the presence of radioactivity would be conducted. Building materials that do not have a radioactive history, have been determined to be free of radioactive contamination, and do not contain hazardous materials would be transported to a recycle facility to the extent possible or a permitted waste disposal facility. S-43 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Materials from buildings that cannot be shown to be suitable for free release27 would be managed as radioactive waste and would be transported to a Federal or commercial radioactive waste disposal facility such as the Nevada National Security Site (NNSS) in Nevada or EnergySolutions in Utah.28 Building materials from structures associated with hazardous waste management or chemical usage permits would be transported to a permitted California Class I or out-of-state hazardous waste disposal facility. Table S–6 shows the estimated quantities of building demolition waste and debris that would be disposed of or recycled by type. A larger quantity of radioactive waste than other types of waste is identified because materials from buildings with a radiological history would be managed as radioactive waste for disposal purposes unless they can be demonstrated to be suitable for free release. Following removal of the slabs and subgrade structures, radiological surveys of building footprints would be conducted. Soil sampling for chemicals and radionuclides would be conducted in accordance with DTSC-approved plans. Any soil encountered above the soil remediation level selected for implementation would be remediated or removed and disposed of during the soil remediation effort. Soil would be replaced to the extent necessary to ensure safe working conditions. Dust and erosion control measures, such as spraying with water, surfactants, or a soil binder and/or covering exposed soil with mulch or straw wattles, would be used to minimize dust and erosion issues until the area is re-contoured and revegetated. Table S–6 Estimated DOE Area IV Building Demolition Materials Type Volume (cubic yards) a From Buildings with a Radioactive History b Low-level radioactive waste 3,280 Mixed low-level radioactive waste Free-released 18 debris c 7,220 Free-released hazardous debris c From Buildings with No Radioactive 110 History b Hazardous waste a b c 120 Recyclable steel, concrete, and asphalt 3,540 Nonhazardous debris 1,220 Volumes estimated from North Wind 2014. Demolition materials would be transported offsite in approximately 1,500 heavy-duty truck loads. For purposes of estimating waste volumes, buildings with no radioactive history include 4038, 4057 Warehouse, 4462, and 4463; all other building were considered to have a radioactive history. Materials from buildings with a radiological history would be managed as radioactive waste for disposal purposes unless they can be demonstrated to be suitable for free release. Free-released debris and free-released hazardous debris do not exhibit radioactivity above background levels. S.10.4 Groundwater Remediation Alternatives S.10.4.1 Background Investigation of bedrock groundwater in Area IV was initiated in 1986 with the installation of a well at the Building 4056 landfill site. Since then, 61 additional bedrock wells have been installed throughout Area IV (two wells were deemed no longer necessary when Building 4059 was removed). Investigation of the near-surface groundwater at SSFL was initiated in March 2001. As part of the investigation of near-surface groundwater, DOE has installed 45 wells (one of which has since been Materials are suitable for free release if they do not exhibit radioactivity above background levels. See Appendix D, Section D.4 for a discussion of the sites that were considered reasonable disposal locations for the different waste types and those that were selected as representative and analyzed in detail in this EIS. 27 28 S-44 Summary closed and sealed). The Area IV groundwater monitoring well network comprises 104 wells: 44 are shallow wells (less than 100 feet deep) and 60 are between 100 feet and 400 feet deep. Approximately 40 wells are sampled each year.29 Figure S–9 illustrates six primary areas of groundwater requiring cleanup within Area IV:       a trichloroethylene (TCE) plume associated with the Former Sodium Disposal Facility (FSDF), a TCE plume associated with the Building 4100/4056 landfill, a perchloroethylene (PCE) plume near Building 4057 Warehouse, a TCE plume associated with the Hazardous Materials Storage Area (HMSA), a tritium plume (associated with the former Building 4010 area), and a strontium-90 source associated with the RMHF leach field. Additionally, there are two other areas with lower concentrations of groundwater contamination, mainly solvents, which are being evaluated: the RMHF TCE plume and the Metals Clarifier TCE plume. The 2010 AOC (DTSC 2010a) incorporated by reference the requirements for investigation and cleanup of groundwater contained in the 2007 CO (DTSC 2007). The 2007 CO directs cleanup to be completed in accordance with RCRA requirements. Groundwater characterization requirements were evaluated during development of the RCRA Facility Investigation Work Plan (CDM Smith 2015a). A RCRA Corrective Measures Study is currently being developed independently from this EIS; the study is to evaluate and select groundwater treatment technologies (e.g., pumping and treatment [commonly called pump and treat], soil vapor extraction, monitored natural attenuation) to be applied as remedial actions. In support of the Corrective Measures Study, DOE has completed collecting hydrogeologic data that will allow modeling of the transport and fate of groundwater contamination and support remedy selection. All groundwater remedies would involve monitoring to confirm modeling assumptions and assess remedy effectiveness. Potential environmental impacts of implementing the groundwater treatment technologies are evaluated in this EIS. DOE may select any or all of these technologies for action depending on the contaminant, source, and location of the impacted groundwater. Because the results of the Corrective Measures Study are yet to be determined, this EIS evaluates the potential impacts that could occur during groundwater remediation activities, assuming implementation of those technologies that would result in the largest potential impacts. DOE anticipates submitting the Corrective Measures Study to DTSC in 2017, prior to the DOE ROD for this EIS. Descriptions of possible groundwater actions are described in the following paragraphs. S.10.4.2 Groundwater No Action Alternative Under the Groundwater No Action Alternative, current groundwater monitoring would continue. DOE would not implement additional monitoring. As part of the SSFL-wide groundwater interim measures, the currently planned FSDF Groundwater Interim Measure would be initiated to extract TCE-contaminated groundwater. Over time, concentrations of radiological and chemical constituents would be reduced through natural attenuation (decay, degradation, dispersion, and dilution). The wells to be sampled and the analyses to be performed are described in the Site-Wide Water Quality Sampling and Analysis Plan, Revision 1, Santa Susana Field Laboratory, Ventura County, California (Haley and Aldrich 2010). 29 S-45 Figure S–9 Area IV Groundwater Plumes Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory S-46 Summary S.10.4.3 Groundwater Monitored Natural Attenuation Alternative Natural attenuation is the process whereby some constituents naturally decrease in concentration over time. Mechanisms include biodegradation, which is the degradation of contamination resulting from naturally occurring microbes, and radioactive decay. Concentrations can also decrease through dilution and dispersion of the chemical in the groundwater. Monitored natural attenuation includes sampling and analysis of groundwater to confirm that the concentrations of constituents of interest are in fact decreasing. Under favorable geochemical and microbial conditions, chlorinated solvents like TCE and PCE have been shown to break down in chemically reducing environments and in the presence of certain naturally occurring microbes; concentrations of these chemicals would be reduced through biodegradation. Under this alternative, no active remediation of any DOE groundwater plumes would occur. In addition to the wells that would continue to be monitored under the No Action Alternative, DOE would propose to DTSC the installation and monitoring of additional wells. The plumes would be sampled (i.e., monitored) on an established schedule to confirm that reduction of the contaminant concentrations continues as anticipated. Monitoring periods would be based on the expected radionuclide decay or natural chemical decomposition over time. Most monitoring would be completed in 10 to 50 years. Monitoring of strontium-90 contamination at the RMHF leach field would last more than 100 years. The time frames for monitoring would be adjusted, based on sampling results. The DOE plumes, the contaminants and their concentration, and the expected time frames for monitoring are listed below (CDM Smith 2015a):  For the FSDF TCE plume, TCE is currently above 1,000 parts per billion, and there are low levels (below the maximum contaminant levels [MCLs]) of perchlorate present (CDM Smith 2015a). The remaining TCE would be monitored for approximately 30 to 50 years until it reached the MCL of 5 parts per billion.  For the HMSA perched groundwater plume with TCE at 90 parts per billion (CDM Smith 2015a), monitoring would continue for approximately 20 years.  For the Building 4100/4056 landfill TCE plume, TCE is currently approximately 48 parts per billion (CDM Smith 2015a). The TCE would be monitored for approximately 20 years.  For the Building 4057 Warehouse PCE plume (currently at 48 parts per billion) (CDM Smith 2015a), monitoring would be needed for approximately 20 years until it reached the MCL of 5 parts per billion.  For the Metals Clarifier TCE plume (currently at 9.3 parts per billion and decreasing) (CDM Smith 2015a), monitoring would be needed for approximately 10 years.  For the RMHF leach field, both strontium-90 and TCE would be monitored. Strontium-90 has a 28.8-year half-life (the period of time required for half of the strontium-90 to decay to a nonradioactive isotope). With an MCL of 8 picocuries per liter and maximum activity concentrations of 183 picocuries per liter in 2010 and 29.5 picocuries per liter in 2015, monitoring would need to continue for 50 to 150 years. For the TCE plume (currently at about 6 parts per billion), monitoring would continue until the 5 parts per billion MCL is reached. The time frame for monitoring is uncertain because TCE in this plume has been relatively constant at approximately 6 parts per billion for about 15 years. This constant concentration is consistent with the conceptual model that assumes that TCE in the bedrock fractures has been removed and the current source is slow, continuous diffusion of TCE from the bedrock matrix. S-47 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory  For the tritium plume, data indicate that radioactive decay would reduce tritium (with a 12.3-year half-life) to its 20,000 picocuries per liter drinking water MCL by 2025. Tritium in the plume was measured at 40,000 picocuries per liter in February 2014 (CDM Smith 2015a). S.10.4.4 Groundwater Treatment Alternative Under the Groundwater Treatment Alternative, treatment would be selected following the completion of a RCRA Corrective Measures Study. The following treatment methods are being considered for groundwater remediation. The plumes with chlorinated solvents (e.g., FSDF, HMSA, Building 4100/4056 landfill, and Building 4057 Warehouse) could be treated using one or a combination of methods including pump and treat, followed by local re-injection of treated water; enhanced groundwater treatment, consisting of in situ treatment such as chemical injection or biological enhancement; or soil vapor extraction. The HMSA perched groundwater plume could also be treated by dewatering (i.e., removing the perched plume by pumping). The RMHF leach field strontium-90 source could be remediated by removing the bedrock that is contaminated with strontium-90 (source removal), source isolation, or lowering the groundwater table by through active pumping. The Metals Clarifier TCE plume and the RMHF TCE plume concentrations are less than 10 parts per million and would not be amenable to treatment. Because the tritium plume would meet its MCL by 2025 through radioactive decay, it would not be addressed by any active treatment. Remediation of these plumes would be accomplished by monitored natural attenuation, as under the Monitored Natural Attenuation Alternative. S.10.5 Preferred Alternative DOE has no preferred alternative at this time. S.11 Summary of Potential Environmental Consequences S.11.1 Comparison of Potential Environmental Consequences of Alternatives This section summarizes the consequence analyses for the alternatives evaluated in this EIS. The summaries are provided in table format for each component of the Area IV and NBZ cleanup. Table S–7 provides the summary of consequences for the soil remediation alternatives, Table S–8 for the building demolition alternatives, and Table S–9 for the groundwater remediation alternatives. S-48 Table S–7 Summary of Potential Environmental Consequences under the Soil Remediation Alternatives Resource Area Land resources Cleanup to AOC LUT Values Alternatives Cleanup to Revised LUT Values S-49 - The land use designation for - Remediation would be consistent with the Area IV and the NBZ would be landowner’s (Boeing’s) intent to maintain its consistent with Ventura County land as undeveloped open space requirements. (Boeing 2016b). - No impacts are expected on use - During 10 years of soil removal, the average of Sage Ranch Park or other daily traffic on Woolsey Canyon Road would recreation areas in the SSFL increase by up to 7.3 percent, which could vicinity. discourage weekday use of Sage Ranch Park. - Electricity and water use would Traffic on evaluated roads other than Woolsey be minimal. Canyon Road is expected to increase by no - No change in aesthetics and more than 2.7 percent, with no expected visual quality from baseline impacts on use of other recreation areas in the conditions. SSFL vicinity. - Electricity use would be minimal. Annual water use would be about 4.0 million gallons; total water use would be about 40 million gallons. Annual use would represent about 0.007 percent of CMWD’s annual supply. Water use is an important consideration because of California’s current drought conditions and Governor Brown’s call to reduce water use (CA EO 2015). - There would be onsite impacts on aesthetics and visual quality during the 10 years of soil removal, but long-term improvements to aesthetics and visual quality resulting from returning Area IV to a stabilized, revegetated state. The terrain would retain the appearance of an open space crossed by roads. No impacts are expected on - No adverse impacts are expected on geologic geologic (bedrock) and (bedrock) resources. paleontological resources (i.e., loss - Potential impacts on paleontological resources of fossils) or onsite soil function. (i.e., loss of fossils) would be minimal because No activities would take place in the Santa Susana Formation containing these zones where earthquake-induced resources is largely located within the landslides could occur. Minimal proposed exemption areas.a Outside of the soil erosion is expected from site proposed exemption areas, about 1 acre of maintenance activities, and there land overlying the Santa Susana Formation would be no need for backfill would be remediated. obtained from offsite sources. - Remediation would be consistent with the landowner’s (Boeing’s) intent to maintain its land as undeveloped open space (Boeing 2016b). - Impacts on recreation areas would be similar to those under the Cleanup to AOC LUT Values Alternative, except that increased traffic would last for slightly more than 2 years. - Electricity use would be minimal. Annual impacts on water would be the same as those under the Cleanup to AOC LUT Values Alternative; total water use would be about 8.3 million gallons. Water use is an important consideration for the same reasons as those under the Cleanup to AOC LUT Values Alternative. - Impacts on aesthetics and visual quality would be similar to those under the Cleanup to AOC LUT Values Alternative, but the impact duration would be less because soil removal would last for slightly more than 2 rather than 10 years. Conservation of Natural Resources - Remediation would be consistent with the landowner’s (Boeing’s) intent to maintain its land as undeveloped open space (Boeing 2016b). - Impacts on recreation areas would be similar to those under the Cleanup to AOC LUT Values Alternative, except that increased traffic would last for about 2 years. - Electricity use would be minimal. Annual impacts on water would be the same as those under the Cleanup to AOC LUT Values Alternative; total water use would be about 8.0 million gallons. Water use is an important consideration for the same reasons as those under the Cleanup to AOC LUT Values Alternative. - Impacts on aesthetics and visual quality would be similar to those under the Cleanup to AOC LUT Values Alternative, but the impact duration would be less because soil removal would last for 2 rather than 10 years. - Impacts on geologic resources would - Impacts on bedrock geologic resources be the same as those under the Cleanup would be the same as those under the to AOC LUT Values Alternative. Cleanup to AOC LUT Values - Potential impacts on paleontological Alternative. resources would be similar to those - Potential impacts on paleontological under the Cleanup to AOC LUT Values resources would be similar to those Alternative, except that only 0.2 acres under the Cleanup to AOC LUT Values of land overlying the Santa Susana Alternative, except less than 0.1 acre of Formation (and not within the land overlying the Santa Susana proposed exemption area) would be Formation (and not within the remediated. proposed exemption area) would be remediated. Summary Geology and soils Soil No Action Soil No Action Geology and soils (cont’d) Surface water resources No changes would occur to the onsite NPDES stormwater control and outfall monitoring system. Radioactive and chemical constituents would remain in soil, representing a source of potential surface water contamination if an unusually large rainstorm that exceeds the design of the NPDES system were to occur. Groundwater resources A source of potential groundwater contamination would remain. There would be no requirement to withdraw site groundwater. Cleanup to AOC LUT Values Alternatives Cleanup to Revised LUT Values - Some activities could take place in zones where earthquake-induced landslides could occur, leading to worker risks that DOE would minimize as needed using the 2010 AOC exemption process. - Soil erosion is possible because of the disturbance of about 130 acres of land, but would be minimized using BMPs, as summarized in Chapter 6. In the periods before completion of stabilization activities, precipitation runoff may erode soil, leading to a reduction of soil quality and functional capability within eroded areas. - About 700,000 cubic yards of backfill would be required, with chemical and radioactive constituents in concentrations meeting AOC LUT values. Loss of soil function is possible if the backfill is not of equal soil quality (including regenerative structures, organic carbon, seed bank, and beneficial soil organisms) to that of current soil at Area IV and the NBZ. No adverse short-term impacts on surface water quality and runoff quantity and velocity are normally expected. During soil remediation, 130 acres would be disturbed. If an unusually large rainstorm were to occur, the design capacity of the existing onsite NPDES stormwater control and outfall monitoring system could be exceeded, resulting in offsite transport of soil and possible overwhelming of regional stormwater control capacity. However, the measures to minimize impacts, as summarized in Chapter 6, would likely forestall this risk. There would be a long-term reduction of potential sources of surface water contamination. No adverse impacts are expected; positive impacts would result from removal of a potential source of groundwater contamination. There would be no requirement to withdraw site groundwater. Conservation of Natural Resources - Potential impacts associated with - Potential impacts associated with earthquake-induced landslides and earthquake-induced landslides and management of worker risks would be management of worker risks would be similar to those under the Cleanup to similar to those under the Cleanup to AOC LUT Values Alternative, but the Revised LUT Values Alternative, but areas of the seismic hazard zones the areas of the seismic hazard zones would be about 8 acres smaller. would be about 0.3 acres smaller. - Potential soil erosion impacts would be - Potential soil erosion impacts would be reduced compared to those under the reduced compared to those under the Cleanup to AOC LUT Values Cleanup to Revised LUT Values Alternative because less acreage would Alternative because less acreage would be disturbed (about 40 acres). be disturbed (about 32 acres). - About 144,000 cubic yards of backfill - About 111,000 cubic yards of backfill would be required, with concentrations would be required, with concentrations of chemicals meeting revised LUT of chemicals and radionuclides meeting values and radionuclides meeting AOC risk-assessment-based values. The LUT values. The Area IV-wide Area IV-wide potential for loss of soil potential for loss of soil function would function would be reduced compared be reduced compared to that under the to under the Cleanup to Revised LUT Cleanup to AOC LUT Values Values Alternative. Alternative. Same as the Cleanup to AOC LUT Values Alternative, except the potential for impacts would be much less because much less acreage (40 acres) would be disturbed. Same as under the Cleanup to Revised LUT Values Alternative, except the potential for impacts would be less because less acreage (32 acres) would be disturbed. Same as the Cleanup to AOC LUT Values Alternative. Same as the Cleanup to AOC LUT Values Alternative. Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory S-50 Resource Area Resource Area Biological resources Cleanup to AOC LUT Values Alternatives Cleanup to Revised LUT Values S-51 No adverse impacts on vegetation - Removal of existing vegetation and topsoil and wildlife habitat and biota; from about 130 acres would increase the aquatic and wetland habitats and difficulty of re-establishing native plant biota; and threatened, endangered, species and would reduce or eliminate the or rare species are expected. value of re-established habitat for most wildlife species. Remediation would require prolonged focused efforts to restore native vegetation and wildlife habitat. If backfill is substantially different from the original topsoil, it may not support re-establishment of native vegetation. About 51 acres of relatively undisturbed native habitat (including coast live oak woodland, northern mixed chaparral, and Venturan coastal scrub) would be affected. There would be fewer impacts within the proposed exemption areas because remediation within these areas would occur via focused removal actions that would minimize soil and habitat disturbance. - Less than one total acre of wetlands, ephemeral drainages, and drainage ditches in upland habitats would be affected. Potential indirect impacts on aquatic and wetland habitats and associated biota, including jurisdictional waters of the U.S., from erosion and movement of sediment or soil would be minimized by use of BMPs and mitigation measures. - Within the proposed exemption areas where most threatened, endangered, or rare species in Area IV and the NBZ are located, as well as critical habitat for two federally listed species, impacts would be minimized through use of focused removal actions. No emissions of pollutants, Pollutants such as VOCs, CO, NOX, SO2, and including CO2, above baseline particulates would be emitted from onsite conditions are expected. activities, with nearly all particulate emissions arising from fugitive dust. Additional emissions would occur from on-road vehicles. A total of 28,000 to 84,000 metric tons of CO2 would be emitted, primarily from vehicles. Conservation of Natural Resources - Impacts on vegetation and wildlife - Impacts on vegetation and wildlife habitat and biota would be reduced habitat and biota would be reduced because the remediated acreage because the remediated acreage (about (40 acres) would be less than that under 32 acres) would be less than that under the Cleanup to AOC LUT Values the Cleanup to AOC LUT Values Alternative. The smaller area affected Alternative. Impacts would be slightly less than those under the Cleanup to by remediation would increase the Revised LUT Values Alternative (32 acres feasibility of restoration, and there vs. 40 acres). The smaller area affected would be more undisturbed habitat by remediation would increase the between remediated portions of the feasibility of restoration, and there site, facilitating recolonization by native would be more undisturbed habitat plant and wildlife species and beneficial between remediated portions of the soil organisms. About 17 acres of site, facilitating recolonization by native relatively undisturbed native habitat plant and wildlife species and beneficial (including coast live oak woodland, soil organisms. About 13 acres of northern mixed chaparral, and relatively undisturbed native habitat Venturan coastal scrub) would be (including coast live oak woodland, affected by remediation activities northern mixed chaparral, and Venturan outside the proposed exemption areas. Impacts within the proposed exemption coastal scrub) would be affected. Impacts within the proposed exemption areas would be generally as described under the Cleanup to AOC LUT Values areas would be generally as described under the Cleanup to AOC LUT Values Alternative. Alternative. - Impacts on aquatic and wetland - Impacts on aquatic and wetland habitats and biota would be similar to habitats and biota would be similar to those under the Cleanup to AOC LUT those under the Cleanup to AOC LUT Values Alternative, but the area of Values Alternative, but the area of ephemeral drainages directly affected ephemeral drainages directly affected would be about 0.4 acres. would be about 0.4 acres. - Impacts on threatened, endangered, or - Impacts on threatened, endangered, or rare species and critical habitat would rare species and critical habitat would be similar to those under the Cleanup be similar to those under the Cleanup to AOC LUT Values Alternative. to AOC LUT Table Values Alternative. The same types of pollutants would be emitted as those under the Cleanup to AOC LUT Values Alternative, but in smaller total quantities. A total of 12,000 to 33,000 metric tons of CO2 would be emitted, primarily from vehicles. The same types of pollutants would be emitted as those under the Cleanup to AOC LUT Values Alternative, but in smaller total quantities. A total of 7,700 to 24,000 metric tons of CO2 would be emitted, primarily from vehicles. Summary Air Quality and climate Soil No Action Soil No Action Noise No noise impacts above baseline conditions are expected. Transportation a No impacts above baseline conditions are expected. Cleanup to AOC LUT Values Alternatives Cleanup to Revised LUT Values - Noise levels from onsite remediation are expected to increase at the closest residence during the 10 years of soil removal, but would be well below 65 dBA CNEL and a 5 dBA CNEL increase, a threshold for potential adverse noise impacts established per the L.A. CEQA Thresholds Guide, Your Resource for Preparing CEQA Analyses in Los Angeles (LA 2006). - No adverse noise impacts from traffic are expected during the 10 years of soil removal, although traffic noise would increase compared to baseline conditions. Timeaveraged daily noise levels at a distance of 100 feet from the evaluated roads could increase by up to 3.5 dBA CNEL, where the final noise level would be below 65 dBA CNEL (the threshold for an adverse impact is an increase of 5 dBA CNEL). Along one section of Valley Circle Boulevard, where the noise level already exceeds 65 dBA CNEL, the noise level would increase by no more than 0.6 dBA CNEL (the threshold for an adverse impact when the final noise level exceeds 65 dBA CNEL is an increase of 3 dBA CNEL). Shipment of radioactive waste – truck option b Shipments – 6,830 truck shipments Incident-free risks: - Crew LCFs: 0 (3×10-4 to 8×10-4) - Population LCFs: 0 (8×10-5 to 2×10-4) Accident risks: - Population LCFs: 0 (4×10-10 to 4×10-9) - Traffic fatalities: 0 (0.04 to 0.3) Conservation of Natural Resources Similar to the Cleanup to AOC LUT Values Alternative, except the duration of increased noise due to site activities or traffic would be slightly more than 2 years. Similar to the Cleanup to AOC LUT Values Alternative, except the duration of increased noise due to site activities or traffic would be 2 years. Shipment of radioactive waste – truck option Same as the Cleanup to AOC LUT Values Alternative. Shipment of radioactive waste – truck option b Shipments – 3,530 truck shipments Incident-free risks: - Crew LCFs: 0 (2×10-4 to 4×10-4) - Population LCFs: 0 (4×10-5 to 1×10-4) Accident risks: - Population LCFs: 0 (2×10-10 to 2×10-9) - Traffic fatalities: 0 (0.02 to 0.1) Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory S-52 Resource Area Resource Area Soil No Action Transportation a (cont’d) No increases in average daily traffic or LOS are expected on roads in the SSFL vicinity, with no traffic-induced damage to road pavement. Alternatives Cleanup to Revised LUT Values Conservation of Natural Resources S-53 Shipment of radioactive waste – truck/rail option b Shipments – 6,830 truck shipments from SSFL to an intermodal facility and then 430 rail shipments Incident-free risks: - Crew LCFs: 0 (1×10-4 to 2×10-4) - Population LCFs: 0 (1×10-4) Accident risks: - Population LCFs: 0 (3×10-10) - Traffic fatalities: 0 (0.2) Shipment of nonradioactive waste, backfill, equipment, and supplies b Truck option: - 110,000 truck shipments - Traffic fatality risks: 1 (0.52) Truck/rail option: - 63,000 truck shipments of waste from SSFL to an intermodal facility, then 3,900 rail shipments; 45,700 truck shipments of backfill, equipment, and supplies - Traffic fatality risks: 3 (2.6) Shipment of radioactive waste – truck/rail option Same as the Cleanup to AOC LUT Values Alternative. Shipment of radioactive waste – truck/rail option b Shipments – 3,530 truck shipments from SSFL to a an intermodal facility, then 220 rail shipments Incident-free risks: - Crew LCFs: 0 (6×10-5 to 1×10-4) - Population LCFs: 0 (5×10-5 to 7×10-5) Accident risks: - Population LCFs: 0 (1×10-10) - Traffic fatalities: 0 (0.1) Shipment of nonradioactive waste, backfill, equipment, and supplies b Truck option: - 17,000 truck shipments - Traffic fatality risks: 0 (0.25) Truck/rail option: - 7,580 truck shipments of waste from SSFL to an intermodal facility and then 470 rail shipments; 9,440 truck shipments of backfill, equipment, and supplies - Traffic fatality risks: 0 (0.32) The weekday average daily traffic on Woolsey Canyon Road would increase by 7.2 to 7.3 percent during 9 years of soil removal and 5.6 percent during the final year. Traffic increases on other evaluated roads would be much smaller. Weekday motorist delays could occur on Woolsey Canyon Road and at its intersection with Valley Circle Boulevard. The LOS for Woolsey Canyon Road could change from a B rating to a C rating (see Appendix H, Table H–19). Other than Woolsey Canyon Road, traffic volumes on the evaluated roads may be reduced by use of multiple routes between SSFL and major highways. Traffic would impose about 200,000 ESALs on the evaluated roads, which would cause damage to the pavement and lead to roads needing repairs sooner than currently anticipated. Impacts would be similar to those under the Cleanup to AOC LUT Values Alternative, except the increased level of traffic would last for a little more than 2 years. Traffic would impose about 51,000 ESALs on the evaluated roads, which would cause less damage than that under the Cleanup to AOC LUT Values Alternative, but would still lead to roads needing repairs sooner than currently anticipated. Shipment of nonradioactive waste, backfill, equipment, and supplies b Truck option: - 14,900 truck shipments - Traffic fatality risks: 0 (0.25) Truck/rail option: - 7,580 truck shipments of waste from SSFL to an intermodal facility and then 470 rail shipments; 7,290 truck shipments of backfill, equipment, and supplies - Traffic fatality risks: 0 (0.31) Impacts would be similar to those under the Cleanup to AOC LUT Values Alternative, except the increased level of traffic would last for about 2 years. Traffic would impose about 40,000 ESALs on the evaluated roads, which would likely cause less damage than that under the Cleanup to Revised LUT Values Alternative, but would still lead to roads needing repairs sooner than currently anticipated. Summary Traffic Cleanup to AOC LUT Values Human health Alternatives Cleanup to Revised LUT Values Soil No Action Cleanup to AOC LUT Values Workers Minimal exposures from monitoring and maintenance activities; workers would be protected from chemical and radiation exposure and industrial hazards through compliance with DOE requirements for worker safety and radiation protection. Workers Exposure would be higher than those under the No Action Alternative during 10 years of soil remediation. Remediation workers would be protected from chemical and radiation exposure through compliance with DOE requirements for worker safety and radiation protection. Radiation protection practices would be employed so that radiation doses are ALARA. Workers The duration of higher exposures would be slightly more than 2 years. Workers would have less exposure to chemically impacted soil than under the Cleanup to AOC LUT Values Alternative; exposure to radioactive constituents would be the same. Remediation worker protection would be the same as under the Cleanup to AOC LUT Values Alternative. Workers The duration of higher exposures would be 2 years. Workers would have less exposure to chemical and radioactive constituents than under the Cleanup to AOC LUT Values Alternative. Remediation worker protection would be the same as under the Cleanup to AOC LUT Values Alternative. Conservation of Natural Resources Valley fever c There would be no change in the risk of exposure to the fungus spores that cause valley fever. Valley fever The potential for exposure of workers and the public to fungus spores would be managed through control of fugitive dust, but would be largest among the action alternatives because of the volume of soil that would be disturbed (933,000 cubic yards). Valley fever The potential for exposure of workers and the public to fungus spores would be managed through control of fugitive dust and would be smaller than that under the Cleanup to AOC LUT Values Alternative because the volume of soil that would be disturbed would be less (192,000 cubic yards). Valley fever The potential for exposure of workers and the public to fungus spores would be the lowest among the action alternatives because the smallest volume of soil would be disturbed (148,000 cubic yards). Members of the public d Hypothetical Onsite Suburban Resident – Cancer risk and toxicity impacts from chemicals and/or radionuclides d in Area IV and the NBZ are comparable to or less than those determined for background soil. Hypothetical Onsite Recreational User – Cancer risk and toxicity impacts from chemical and/or radionuclides e in Area IV and the NBZ are comparable to or less than those determined for background soil. Members of the public Chemically and radioactively impacted soil exceeding AOC LUT values would be removed. Thereafter, risks to a hypothetical onsite suburban resident or recreational user would be less than those under the No Action Alternative. Members of the public Chemically impacted soil exceeding revised LUT values would be removed, as would radioactively contaminated soil exceeding AOC LUT values. Thereafter, risks to a hypothetical onsite suburban resident or recreational user would be less than those under the Soil No Action Alternative, but more than those under the Cleanup to AOC LUT Values Alternative. Members of the public Chemically and radioactively impacted soil exceeding risk assessment-based values would be removed. Thereafter, risks to a hypothetical onsite suburban resident or recreational user would be less than those under the Soil No Action Alternative, but more than those under the Cleanup to AOC LUT Values or Cleanup to Revised LUT Values Alternative. Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory S-54 Resource Area Resource Area Waste management Cultural resources Alternatives Cleanup to Revised LUT Values Cleanup to AOC LUT Values Very small quantities of waste from site maintenance activities may be annually generated, which would be transported to offsite waste management facilities with no impacts on the disposal capacities of these facilities. No archaeological or architectural cultural resources would be affected. No adverse impacts are expected on traditional cultural resources. LLW/MLLW – 91,000 cubic yards Hazardous waste – 49,000 cubic yards Nonhazardous waste – 793,000 cubic yards No exceedance of total waste capacity or a daily or annual waste acceptance limit is expected at any evaluated facility. LLW/MLLW – 91,000 cubic yards Hazardous waste – 49,000 cubic yards Nonhazardous waste – 52,000 cubic yards No exceedance of total waste capacity or a daily or annual waste acceptance limit is expected at any evaluated facility. LLW/MLLW 47,000 cubic yards Hazardous waste – 49,000 cubic yards Nonhazardous waste – 52,000 cubic yards No exceedance of total waste capacity or a daily or annual waste acceptance limit is expected at any evaluated facility. Conservation of Natural Resources Archaeological and architectural cultural resources would not be affected. During 10 years of soil removal, adverse impacts on the integrity of traditional cultural resources are possible from changes in setting, augmented site access during remediation, disturbance of landscape (130 acres), and potential discovery of unanticipated archaeological sites. Archaeological and architectural cultural resources would not be affected. Adverse impacts on the integrity of traditional cultural resources are possible, similar to those under the Cleanup to AOC LUT Values Alternative, but less likely. There would be reduced changes in setting because soil removal and site access would occur for slightly more than 2 years, with less disturbance of landscape (40 acres) and less soil removed, which would reduce the potential for discovery of unanticipated archaeological sites. Archaeological and architectural cultural resources would not be affected. Adverse impacts on the integrity of traditional cultural resources are possible, similar to those under the Cleanup to Revised LUT Values Alternatives, but less likely. There would be slightly reduced changes in setting because soil removal and site access would occur for 2 years, with less disturbance of landscape (32 acres) and less soil removed, which would further reduce the potential for discovery of unanticipated archaeological sites. Summary Soil No Action S-55 Socioeconomics Soil No Action Cleanup to AOC LUT Values Alternatives Cleanup to Revised LUT Values No socioeconomic impacts on - Employment would increase by 25 workers employment, businesses, for 10 years, with minor beneficial infrastructure and municipal socioeconomic impacts. services, housing, or local - Truck traffic in the SSFL vicinity would last government revenue are expected for 10 years, but is not expected to have in Los Angeles and Ventura socioeconomic impacts on businesses on the Counties. No traffic-related evaluated routes between SSFL and major impacts are expected at offsite highways. disposal facilities. - Traffic could damage road pavement along segments of the routes to major highways, which could affect government finances. DOE may need to negotiate with local governments to contribute its portion of the cost for maintenance and repair of affected roads. No other impacts on municipal services are expected. - Workers would be primarily employed from the SSFL ROI, with no impacts on housing availability. - Revenue from taxes from purchases of materials and fuel and rental of equipment, as well as permitting fees for project activities, could increase revenues for local governments during the 10 years of remediation. - Because of the small numbers of daily deliveries of soil to the evaluated radioactive and hazardous waste facilities, no socioeconomic impacts are expected on businesses near these facilities. For deliveries of nonhazardous soil to the evaluated facilities, no or minimal socioeconomic impacts are expected on businesses near these facilities. Disposal fees could increase revenues for public or private entities. Any adverse impacts may be reduced by shipping soil waste to multiple authorized disposal facilities, using multiple local routes (as available) to a disposal facility, or shipping waste by rail to rail-accessible facilities. - Employment would increase by 25 workers for slightly more than 2 years, with minor beneficial socioeconomic impacts. - Truck traffic in the SSFL vicinity would last for slightly more than 2 years, but is not expected to have socioeconomic impacts on businesses on the evaluated routes between SSFL and major highways. - Same as under the Cleanup to AOC LUT Values Alternative, except there would be fewer truck round trips, which would have a smaller potential for damage of road pavement. - Impacts on housing availability would be the same as those under the Cleanup to AOC LUT Values Alternative. - Potential funding impacts and benefits would be reduced compared to those under the Cleanup to AOC LUT Values Alternative because of the shorter operational duration of slightly more than 2 years. - Similar disposal facility impacts as those under the Cleanup to AOC LUT Values Alternative, except that there would be increased daily deliveries to evaluated radioactive and hazardous waste facilities, and significantly reduced daily and total deliveries to the evaluated nonhazardous waste facilities. There would be reduced disposal fees at the evaluated hazardous waste facilities. No socioeconomic impacts on businesses are expected from delivery of waste to any evaluated facility. Conservation of Natural Resources - Employment would increase by 25 workers for 2 years, with minor beneficial socioeconomic impacts. - Truck traffic in the SSFL vicinity would last for 2 years, but is not expected to have socioeconomic impacts on businesses on the evaluated routes between SSFL and major highways. - Same as under the Cleanup to Revised LUT Values Alternative, except there would be fewer truck round trips, which would have a smaller potential for damage of road pavement. - Impacts on housing availability would be the same as those under the Cleanup to AOC LUT Values Alternative. - Potential funding impacts and benefits would be reduced compared to those under the Cleanup to Revised LUT Values Alternative because of the slightly shorter operational duration of 2 years. - Similar disposal facility impacts as those under the Cleanup to Revised LUT Values Alternative, except that shipments to radioactive waste facilities would be reduced, meaning that disposal fees that could provide revenues for public or private entities also would be reduced. No socioeconomic impacts on businesses are expected from delivery of waste to any evaluated facility. Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory S-56 Resource Area Resource Area Environmental justice Soil No Action Cleanup to AOC LUT Values Alternatives Cleanup to Revised LUT Values Conservation of Natural Resources evaluated disposal facilities could be reduced. No disproportionately high and adverse impacts are expected on Native American tribes and minority and low-income populations in the regional ROIs. Summary - Potential risks to a hypothetical - After remediation, potential risks to a - Impacts on Native American tribes and - Impacts on Native American tribes and (after 100 years) onsite hypothetical onsite suburban resident or minority and low-income populations minority and low-income populations suburban resident or recreational user would be extremely low. No in the SSFL ROI and in the vicinities of in the SSFL ROI and in the vicinities of recreational user would be disproportionately high and adverse impacts the disposal facilities would be similar disposal facilities would be similar to extremely low (see Human are expected on Native American tribes and to those under the Cleanup to AOC those under the Cleanup to AOC LUT Health). No disproportionately minority and low-income populations in the LUT Values Alternative, except that Values Alternative, except that they high and adverse impacts are SSFL ROI. they would last for slightly more than 2 would last for 2 years. No expected on Native American - During the 10 years of soil removal, weekday years. No disproportionately high and disproportionately high and adverse tribes and minority and lowtraffic in the SSFL ROI would increase, but adverse impacts are expected on Native impacts are expected on Native income populations in the SSFL the evaluated routes would traverse minority American tribes and minority and lowAmerican tribes and minority and lowROI. and non-minority communities, as well as income populations. income populations. - No traffic impacts above low-income and non-low-income baseline conditions are expected communities, and would not pass through in the SSFL ROI. No Native American lands. This indicates that disproportionately high and traffic impacts on Native American, minority, adverse impacts are expected on or low-income populations would be the same Native American tribes and as those experienced by the general minority and low-income population. No disproportionately high and populations in the SSFL ROI. adverse impacts are expected in the SSFL - No traffic impacts above ROI. baseline conditions are expected - There would be no noticeable increase in traffic in the vicinities of the disposal facilities evaluated in the regional ROIs. No for receipt of radiologically contaminated or disproportionately high and hazardous soil, as well as no or minimal impacts adverse impacts are expected on in the vicinities of the facilities evaluated for Native American tribes and receipt of nonhazardous soil. By using multiple minority and low-income disposal facilities or rail transport to railpopulations in the regional accessible facilities, traffic in the vicinities of the ROIs. S-57 Sensitive-aged populations Soil No Action Cleanup to AOC LUT Values Alternatives Cleanup to Revised LUT Values Conservation of Natural Resources - No traffic impacts above - During the 10-year duration of soil removal, - Impacts in the SSFL ROI would be - Impacts in the SSFL ROI would be baseline conditions are expected there could be an increased risk to pedestrians similar to those under the Cleanup to similar to those under the Cleanup to in the SSFL ROI, with no along or crossing Woolsey Canyon Road, but AOC LUT Values Alternative, except AOC LUT Values Alternative, except disparate impacts (markedly this risk would be experienced by persons of that increased traffic would occur for that increased traffic would occur for distinct impacts relative to those all ages. There is not expected to be a slightly more than 2 rather than 2 rather than 10 years. on the general population) on significantly larger population of sensitive10 years. - Similar traffic increases would occur in sensitive-aged populations. aged persons in the group that could - Compared to under the Cleanup to the regional ROIs containing - No traffic impacts above experience this risk compared to groups of AOC LUT Values Alternative, there radioactive, hazardous, and baseline conditions are expected persons living elsewhere in the SSFL ROI. would be larger traffic increases in the nonhazardous waste disposal facilities in the regional ROIs, with no Traffic volumes, and therefore risks, to regional ROIs containing radioactive as those under the Cleanup to Revised disparate impacts on sensitivepedestrians along other evaluated routes are and hazardous waste disposal facilities LUT Values Alternative, except that the aged populations. not expected to be noticeably larger than and smaller traffic increases in the increased traffic to each type of facility those under baseline conditions. No disparate regional ROIs containing nonhazardous would be of a shorter duration, with the impacts on sensitive-aged populations are waste facilities. Increased traffic would longest duration being 2 years. No expected in the SSFL ROI. occur for slightly more than 2 years. disparate impacts are expected on - There would be no or minimal impacts due to No disparate impacts are expected on sensitive-aged populations in the increased traffic in the regional ROIs. Using sensitive-aged populations in the regional ROIs. multiple facilities or rail transport to railregional ROIs. accessible facilities, traffic may be reduced along any route that may pass near a school or recreation area. No disparate impacts are expected on sensitive-aged populations in the regional ROIs. ALARA = as low as reasonably achievable; AOC = Administrative Order on Consent for Remediation; BMP = best management practice; Boeing = The Boeing Company; CO = carbon monoxide; CO2 = carbon dioxide; CMWD = Calleguas Municipal Water District; CNEL = community noise equivalent level; dBA = decibels A-weighted; ESAL = equivalent single-axle load; LCF = latent cancer fatality; LLW = low-level radioactive waste; LOS = level of service; LUT = Look-Up Table; MLLW = mixed low-level radioactive waste; NBZ = Northern Buffer Zone; NOX = nitrogen oxides; NPDES = National Pollutant Discharge Elimination System; ROI = region of influence; SO2 = sulfur dioxide; VOC = volatile organic compound. a “Proposed exemption areas” refers to areas that are identified for the protection of biological and cultural resources in accordance with the 2010 AOC (DTSC 2010a). DOE would not take action in the proposed exemption areas unless it is demonstrated that levels of chemical or radioactive constituents in the soil would pose a risk to human health or the environment, as determined using risk-based screening levels from the Final Standardized Risk Assessment Methodology Revision 2 Addendum, Santa Susana Field Laboratory, Ventura County, California (MWH 2014). b Transportation risks are presented as whole numbers with the actual calculated values presented in parentheses. Values in parentheses that have a negative power of 10 are less than 1. The larger the negative value of 10, the smaller the number. c Valley fever is the initial form of coccidioidomycosis infection, a fungal infection caused by inhalation of airborne Coccidioides spp. spores that are present in certain arid soils. Spores from the fungus are found in the top 2 to 12 inches of soil in many parts of arid United States southwest. When soil containing this fungus is disturbed by activities such as digging or by the wind, the fungal spores can get into the air (CDC 2014; HESIS 2013). d Because members of the public would be restricted from accessing the site through fencing, signage, and routine patrols by site security personnel, and DOE’s intent would be to prevent public access to the site, impacts calculated for the onsite suburban resident and recreational user under the Soil No Action Alternative are hypothetical. e All impacts for soil constituents are based on the mean (for chemicals) or median (for radionuclides) concentration for all constituents that had one or more exceedances of the LUT values. Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory S-58 Resource Area Table S–8 Summary of Potential Environmental Consequences under the Building Demolition Alternatives Alternatives Resource Area Land resources Geology and soils Building No Action Building Removal of soil function is possible if the backfill is not of equal soil quality, including the presence of regenerative structures, organic carbon, seed bank, and beneficial soil organisms, as that for current soil at Area IV. Because most of the area Surface water resources Groundwater resources No changes in surface water quality and stormwater runoff quantity and velocity from existing conditions are expected. Sources of potential surface water contamination would remain. No adverse impacts on groundwater quality and quantity are expected. to be disturbed is currently occupied by buildings or asphalt, soil quality and functional capability would likely be already reduced compared to that before development of Area IV. During building demolition, no adverse impacts on surface water quality are expected from stormwater runoff. Sources of potential surface water contamination would be removed. No increases in runoff quantity and velocity are expected that could overwhelm SSFL or regional stormwater control capacities. No adverse impacts are expected on groundwater quality. This alternative may require dewatering of the basement of Building 4024 to enable safe demolition. If this occurs, up to 200,000 gallons of groundwater could be withdrawn from Area IV that would be managed by methods such as treatment (as needed) and onsite discharge. Summary - The land use designation for Area IV would be - After removal of DOE-owned buildings, the remediated area would be consistent with the landowner’s consistent with Ventura County requirements. (Boeing’s) intent to maintain its land as undeveloped open space (Boeing 2016b). - No impacts on use of Sage Ranch Park or - If waste and backfill were shipped over a 2- to 5-month period in each working year, the average daily traffic on other recreation areas in the SSFL vicinity are Woolsey Canyon Road would increase by up to 5.3 percent, which could discourage weekday use of Sage Ranch expected. Park. But if waste and backfill were shipped throughout each working year, the average daily traffic on Woolsey - Electrical service to DOE-owned buildings Canyon Road would increase by less than 1 percent, which would be unlikely to discourage weekday use of Sage would be severed, but electrical service in Ranch Park. No impacts on the use of other recreation areas in the SSFL vicinity are expected; nonetheless, Area IV would remain. Electrical and water traffic on other roads past other recreation areas may be reduced by routing truck traffic among multiple routes requirements would continue to be minimal. between SSFL and major highways. - No short-term changes to the aesthetics and - Annual electricity requirements would be minimal. About 315,000 gallons of water from CMWD would be visual quality of Area IV are expected, but annually used during 2 years. Although this annual water use would represent about 0.0005 percent of CMWD’s DOE-owned buildings could dilapidate over annual supply, water use is an important consideration because of California’s current drought conditions and time, decreasing aesthetics and visual quality. Governor Brown’s call for a statewide 25 percent reduction in potable water use (CA EO 2015). - There would be impacts on views of Area IV during the 2 years of building demolition, but long-term improvements to Area IV visual quality from returning the area to a stabilized, revegetated state. No impacts on geologic and paleontological - No adverse impacts are expected on bedrock geologic resources. - Minimal impacts are expected on paleontological resources during building removal. resources are expected, and no worker activities - No risks to workers are expected from potential earthquake-induced landslides because building removal would would take place in zones where earthquakeoccur outside of zones where such landslides could occur; however, in the event of an earthquake, there could be induced landslides could occur. No impacts a risk to demolition workers resulting from building collapse. from soil erosion or loss of soil function are expected, and there would be no need for backfill - Soil erosion would be minimized using BMPs, as summarized in Chapter 6. However, in the period between building removal and completion of site stabilization efforts, disturbed soil could erode, leading to some obtained from offsite sources. reduction of soil quality and functional capability within eroded areas. Because most of the area to be disturbed is currently occupied by buildings or asphalt, soil quality and functional capability within potentially eroded areas would likely be already reduced compared to that before development of Area IV. - Up to 13,500 cubic yards of backfill would be required, with chemical and radioactive constituents in concentrations meeting prescribed values (e.g., AOC LUT, revised LUT, or risk-assessment-based values).a Loss S-59 Building No Action Biological resources No adverse impacts on vegetation and wildlife habitat and biota; aquatic and wetland habitats and biota; or threatened, endangered, or rare species are expected. Air quality and climate No emissions of airborne pollutants, including greenhouse gases, above baseline conditions are expected. Noise No noise impacts from onsite activities or from traffic to and from SSFL above baseline conditions are expected. Transportation b No impacts above baseline conditions are expected. Building Removal - Removal of buildings would not be expected to cause measureable loss of native plant and wildlife communities, although habitat would be lost for native wildlife species using the buildings for roosting or nesting, with potential disturbance of MBTA-protected species. There would be offsetting beneficial impacts on native wildlife from elimination of habitat for nuisance species and creation of restored habitat after the buildings are removed. If backfill is substantially different from soil present before development of Area IV, it may not support restoration of vegetation similar to that previously present. - Wetlands or jurisdictional waters of the United States would not be directly impacted. Existing drainage structures and impervious surfaces may be removed, but replaced by more natural drainage patterns. Indirect impacts from runoff would be minimized by use of BMPs and mitigation measures. - Impacts on special-status animal species or their habitats would be short-term, may be mitigated or avoided, and would be unlikely to result in take of listed wildlife species. Adverse impacts on individual Santa Susana tarplants could occur if they are established next to buildings at the time that demolition occurs. No other special-status plant species are likely to be impacted because none have been observed or would be expected in the already disturbed areas adjacent to the buildings. Emissions of pollutants such as VOCs, CO, NOX, SO2, and particulates would occur from onsite activities, with nearly all particulate emissions arising from fugitive dust; additional emissions would occur from vehicles, including those transporting waste and backfill. A total of 1,800 to 3,900 metric tons of CO2 would be emitted, primarily from vehicles. Noise levels at the closest residence to Area IV are expected to be well below 65 dBA CNEL, with no expected adverse noise impacts. No adverse noise impacts are expected from traffic along the evaluated routes between SSFL and major highways. Time-averaged daily noise levels at a distance of 100 feet from the evaluated roads could increase by up to 3.5 dBA CNEL, where the final noise level would be below 65 dBA CNEL (the threshold for an adverse impact is an increase of 5 dBA CNEL). Along one section of Valley Circle Boulevard, where the noise level already exceeds 65 dBA CNEL, the noise level would increase by no more than 0.6 dBA CNEL (the threshold for an adverse impact when the final noise level exceeds 65 dBA CNEL is an increase of 3 dBA CNEL). Shipment of radioactive waste – truck option b Shipments – 1,030 truck shipments Incident-free risks: - Crew LCFs: 0 (5×10-5 to 1×10-4) - Population LCFs: 0 (1×10-5 to 3×10-5) Accident risks: - Population LCFs: 0 (5×10-11 to 6×10-10) - Traffic fatalities: 0 (6×10-3 to 4×10-2) Shipment of radioactive waste – truck/rail option b Shipments – 1,030 truck shipments from SSFL to an intermodal facility, then 65 rail shipments Incident-free risks: Accident risks: - Crew LCFs: 0 (2×10-5 to 4×10-5) Population LCFs: 0 (4×10-11) - Population LCFs: 0 (2×10-5) Traffic fatalities: 0 (3×10-2) - Shipment of nonradioactive waste, backfill, equipment, and supplies b Truck option: Truck/rail option: - 1,400 truck shipments of waste, backfill, equipment, - 130 truck shipments of hazardous/nonhazardous waste and supplies from SSFL to an intermodal facility, and then 10 rail - Traffic fatality risks: 0 (2.3 × 10-3) shipments; plus 1,260 truck shipments of recyclable material, backfill, equipment, and supplies Traffic fatality risks: 0 (7.0 × 10-3) Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory S-60 Alternatives Resource Area Alternatives Resource Area Building No Action No increases in average daily traffic or LOS on roads in the SSFL vicinity are expected, with no traffic-induced damage to road pavement. Human health Workers Exposures from monitoring and maintenance activities would be minimal. Workers would be protected from radiation exposure and industrial hazards through compliance with DOE requirements for worker safety and radiation protection. Building Removal The weekday average daily traffic on Woolsey Canyon Road would increase by about 3.4 percent in the first year of the project and 5.3 percent in in the second year, leading to potential weekday motorist delays on this road, assuming waste and backfill shipments occurred during a 2- to 5-month period in each working year. Traffic increases on other evaluated roads would be smaller. Increases in weekday average daily traffic on Woolsey Canyon Road could be reduced to less than 1 percent, with corresponding reductions on other roads, assuming waste and backfill shipments were made throughout each working year. Except for Woolsey Canyon Road, traffic on the evaluated roads may be further reduced by distributing traffic among multiple routes between SSFL and major highways. Assuming waste and backfill shipments are made during 2 to 5 months in each year, the LOS for Woolsey Canyon Road could change from a B rating to a C rating. No change in LOS rating would be expected if waste and backfill shipments were made throughout each working year. LOS ratings for other roads are not expected to change. Truck traffic would impose about 5,200 ESALs on the evaluated routes between SSFL and major highways. This increased traffic would likely have some adverse impacts on road pavement, so that the affected roads may require repair sooner than currently anticipated. Workers Conservatively assuming no reduction in exposure as D&D progresses, impacts would be: Individual worker - Dose: 240 millirem per year - Project LCF risk: 1 in 10,000 Worker population - Total Dose: 12.5 person-rem - Project LCFs: 0 (0.003) Building demolition workers would be protected from radiation exposure and industrial hazards through compliance with DOE requirements for worker safety and radiation protection. Members of the public No impacts are expected because access to the buildings would be restricted. Waste management Members of the public No impacts are expected during building removal. Following building removal, there would be no impacts attributable to the buildings to a hypothetical onsite suburban resident or recreational user. Any residual impacts would be associated with chemicals or radionuclides in the soil (see Table S–7). Very small quantities of waste from site LLW/MLLW – 10,600 cubic yards maintenance activities may be annually generated, Hazardous waste – 120 cubic yards which would be transported to offsite waste Nonhazardous waste – 1,220 cubic yards management facilities with no impacts on the Recyclable material – 3,540 cubic yards disposal capacities of these facilities. No exceedance of total waste capacity or a daily or annual waste acceptance limit is expected at any evaluated facility. Summary Traffic S-61 Building No Action Cultural resources No archaeological or structural cultural resources would be affected. No adverse impacts on traditional cultural resources are expected. Socioeconomics No socioeconomic impacts on employment, regional truck traffic, infrastructure and municipal services, housing, and local government revenue are expected in Los Angeles and Ventura Counties. No socioeconomic impacts are expected on businesses in the vicinities of the offsite recycle and disposal facilities. Environmental justice Building Removal No adverse effects are expected on archaeological or architectural cultural resources; nor would adverse impacts be expected on traditional cultural resources. - Building removal would employ 26 workers with minor beneficial socioeconomic impacts. - Increased traffic during 2 years of building demolition is not expected to have socioeconomic impacts on businesses along the evaluated routes between SSFL and major highways. - Road pavement deterioration would increase expenses for local governments. DOE may need to negotiate with local governments to contribute its portion of the cost for maintenance and repair of affected roads. No other impacts are expected on municipal services such as police or fire services. Because workers would be primarily employed from Los Angeles and Ventura Counties, workers would already be living in the ROI and would not need new housing. Therefore, there would be no impacts on housing availability - Potential increased expenses for local governments in the SSFL ROI due to pavement deterioration could be countered by potential increased tax revenues due to purchases of materials and fuel and rental of equipment, as well as permitting fees for project activities. - No noticeable increases in traffic volumes are expected at the evaluated recycle and disposal facilities, with no expected socioeconomic impacts on businesses in the regional ROIs. No human health impacts are expected on - No impacts are expected on members of the public during building removal; following building removal, there members of the public. There would be no would be no impacts on an onsite suburban resident or recreational user that would be attributable to the increases in traffic above baseline conditions in buildings. Therefore, no high and disproportionate adverse impacts are expected on Native American tribes and the SSFL and regional ROIs, and thus, no minority or low-income populations in the SSFL ROI. additional traffic-related impacts. Therefore, no - Traffic in the SSFL ROI would increase, but the evaluated routes between SSFL and major highways would disproportionately high and adverse impacts are traverse minority and non-minority communities, as well as low-income and non-low-income communities, and expected on Native American tribes and minority would not pass through Native American lands. This indicates that traffic impacts on Native American, or low-income populations in the SSFL ROI and minority, or low-income populations would be the same as those experienced by the general population. the regional ROIs. Therefore, no disproportionately high and adverse traffic-related impacts are expected on Native American tribes and minority and low-income populations in the SSFL ROI. - There would be no noticeable increase in heavy-duty truck traffic in the vicinities of the evaluated recycle and disposal facilities. Nonetheless, use of multiple facilities or rail transport to rail-accessible facilities would reduce truck traffic in the vicinities of the evaluated facilities. Therefore, no disproportionately high and adverse impacts are expected on Native American tribes and minority and low-income populations in the regional ROIs. Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory S-62 Alternatives Resource Area Alternatives Resource Area Building No Action Building Removal Sensitive-aged populations There would be no increases in traffic above - Assuming shipment of waste and backfill occurs during a 2- to 5-month period in each working year, there could baseline conditions in the SSFL ROI or the be an increased risk to pedestrians along or crossing Woolsey Canyon Road, but this risk would be experienced regional ROIs, and thus, no disparate impacts by persons of all ages. Traffic volumes could be reduced by instead shipping waste and backfill throughout each (markedly distinct impacts relative to those on working year, and, on other than Woolsey Canyon Road, by using multiple routes between SSFL and major the general population) are expected on sensitivehighway systems, thereby reducing traffic on any evaluated road that may pass by or near a school or recreation aged populations. area. Therefore, no disparate impacts on sensitive-aged populations are expected in the SSFL ROI. - There would be no noticeable increase in heavy-duty truck traffic in the vicinities of the evaluated recycle and waste disposal facilities. Nonetheless, use of multiple recycle and disposal facilities or rail transport to railaccessible facilities could reduce traffic through communities or locations (e.g., schools, recreation areas) where sensitive-aged populations may be present along the transit routes. Therefore, no disparate impacts are expected on sensitive-aged populations in the regional ROIs. AOC = Administrative Order on Consent for Remediation; BMP = best management practice; Boeing = The Boeing Company; CO = carbon monoxide; CO2 = carbon dioxide; CMWD = Calleguas Municipal Water District; CNEL = Community Noise Equivalent Level; D&D = decontamination and decommissioning; dBA = decibels A-weighted; ESAL = equivalent single-axle load; LCF = latent cancer fatality; LLW = low-level radioactive waste; LOS = level of service; LUT = Look-Up Table; MBTA = Migratory Bird Treaty Act; MLLW = mixed low-level radioactive waste; NOX = nitrogen oxide; ROI = region of interest; SO2 = sulfur dioxide; VOC = volatile organic compound. a Estimates of backfill volume range from 8,140 cubic yards to 13,500 cubic yards (see Appendix D); the larger estimate (13,500 cubic yards) was used for analysis in this EIS. b Transportation and human health population risks are presented as whole numbers, with the actual calculated values presented in parentheses. Values in parentheses that have a negative power of 10 are less than 1. The larger the negative value of 10, the smaller the number. Summary S-63 Resource Area Land resources Geology and soils Surface water resources Groundwater No Action - The land use designation for Area IV and the NBZ would be consistent with Ventura County requirements. - No impacts on use of Sage Ranch Park or other recreation areas in the SSFL vicinity are expected. - Electrical and water requirements would continue to be minimal. - There would be no change in Area IV aesthetics and visual quality from baseline conditions. Alternatives Groundwater Monitored Natural Attenuation - No change is expected in land use designation. - The minimal additional traffic would not restrict access to or impact activities at Sage Ranch Park or other recreation areas in the SSFL vicinity. - Electricity requirements would be minimal. A total of 5,000 gallons of water from CMWD would be used during installation of five monitoring wells, which would represent about 9 × 10-6 percent of CMWD’s annual supply. - There would be visual impacts during well installation due to views of drill rigs and supporting equipment. These impacts would occur for less than 1 year. Monitoring activities would not alter Area IV aesthetics or visual quality compared to baseline conditions. Groundwater Treatment - No change is expected in land use designation. - Traffic volumes would be larger than those under the Groundwater Monitored Natural Attenuation Alternative, but would not restrict access to, or impact activities at, Sage Ranch Park or other recreation areas in the SSFL vicinity. - Electricity requirements would be minimal. A total of 8,000 gallons of water from CMWD would be used for dust suppression during bedrock removal, which would represent about 1 × 10-5 percent of CMWD’s annual supply. - There would be visual impacts during groundwater treatment system construction and operation due to the presence of water storage tanks, treatment units and other structures, and overland piping. These impacts would occur during 0.5 years of treatment system installation, followed by 5 years of treatment system operation. Long-term views at Area IV would be similar to baseline conditions. No impacts on geologic (bedrock) and Same as under the Groundwater No Action Alternative, - Loss of 1,050 cubic yards of subsurface bedrock. paleontological resources are expected. except there would be a minimal potential for soil erosion - No impacts are expected on paleontological resources. No activities would take place in zones and loss of soil function during well installation. - No activities would take place in zones where earthquake-induced where earthquake-induced landslides landslides could occur. could occur. No soil erosion or loss of - There would be minimal risk of soil loss due to erosion. soil function is expected from well - Loss of soil function may occur at some treatment system locations monitoring activities, and there would during the installation of groundwater treatment systems, including be no need for backfill obtained from overland piping, and during the subsequent projected 5 years of offsite sources. treatment system operations. - About 1,280 cubic yards of backfill would be required, with chemicals and radionuclides in concentrations meeting prescribed values (e.g., AOC LUT, revised LUT, or risk-assessment-based values). No short-term changes from baseline No adverse impacts on surface water quality during well No adverse impacts on surface water quality during treatment system conditions on surface water quality are installation and well monitoring. Long-term reduction of installation and operation. The time required to eliminate sources of expected, although there would be a sources of potential surface water contamination. No potential surface water contamination would be much shorter than long-term reduction of sources of adverse impacts on SSFL or regional stormwater control that under the Groundwater Monitored Natural Attenuation potential surface water contamination. capacities are expected. Alternative. No adverse impacts on SSFL or regional stormwater No change from baseline conditions on control capacities are expected. stormwater runoff quantity and velocity are expected. Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory S-64 Table S–9 Summary of Potential Environmental Consequences under the Groundwater Remedial Alternatives Resource Area Groundwater resources Biological resources Groundwater No Action No additional adverse impacts on groundwater quality are expected. Groundwater quality would improve over time as chemical and radioactive constituents attenuate or decay. There would be no requirement to withdraw site groundwater above baseline conditions. Minor adverse impacts on vegetation and wildlife habitat and biota would occur from groundwater monitoring operations. No adverse impacts on aquatic and wetland habitats and biota or threatened, endangered, or rare species are expected. No emissions of airborne pollutants, including greenhouse gases, above baseline conditions are expected. Noise No noise impacts above baseline conditions from onsite activities or from traffic to and from SSFL are expected. Groundwater Treatment The same impacts on groundwater quality are expected as No adverse impacts on groundwater quality or quantity are expected. those under the Groundwater No Action Alternative. Positive impacts on water quality would result from removal of There could be slightly increased withdrawals of Area IV contamination sources or treatment of groundwater. groundwater as part of groundwater monitoring operations. Five new wells would be installed. Because these wells would be installed generally in previously disturbed areas, impacts on vegetation and wildlife habitat and biota from periodic groundwater sampling would be minor and localized. No adverse impacts on aquatic and wetland habitats and biota are expected. If a monitoring well were installed in a proposed exemption area, BMPs and mitigation measures would avoid or minimize adverse impacts of well installation and monitoring on threatened, endangered, or rare species; no adverse impacts on these species are expected from monitoring activities outside the proposed exemption areas. Minor quantities of pollutants such as VOCs, CO, NOX, SO2, and particulates would be emitted during monitoring well installation and groundwater monitoring and from on-road vehicles. Minimal emissions of CO2 are expected. Noise levels at the closest residence could increase slightly compared to those under the Groundwater No Action Alternative, but are still expected to be well below 65 dBA CNEL, with no adverse noise impacts. There could be 11 heavy-duty truck round trips distributed over a working year, with no expected adverse traffic-related noise impacts. Impacts on vegetation and wildlife habitat and biota would be larger than those under the Groundwater Monitored Natural Attenuation Alternative, but nonetheless localized and minor. Installation of groundwater treatment systems would generally be in previously disturbed habitats, with localized and minor impacts. Assuming sandstone bedrock containing strontium-90 source is removed, up to 0.25 acre of previously disturbed land near RMHF would be affected. No adverse impacts are expected on aquatic and wetland habitats and biota. Potential impacts on threatened, endangered, or rare species would be minimal as described under the Groundwater Monitored Natural Attenuation Alternative. Small quantities of VOCs, CO, NOX, SO2, and particulates would be emitted during bedrock removal and treatment system installation. Additional emissions would occur from on-road vehicles. A total of 180 to 360 metric tons of CO2 would be emitted, primarily from vehicles. Noise levels from onsite activities at the closest residence could slightly increase compared to those under the Groundwater Monitored Natural Attenuation Alternative, but are still expected to be well below 65 dBA CNEL, with no adverse noise impacts. Summary Air quality and climate Alternatives Groundwater Monitored Natural Attenuation S-65 Transportation a Groundwater No Action No impacts above baseline conditions are expected. Alternatives Groundwater Monitored Natural Attenuation Shipment of nonhazardous waste, equipment, and supplies a, b Shipments – 280 shipments by truck. Traffic fatality accident risks – 0 (1.5×10-4) Traffic No increases in average daily traffic or LOS on roads in the SSFL vicinity are expected, with no traffic-induced damage to road pavement. The weekday average daily traffic on Woolsey Canyon Road would increase by 0.16 percent during 1 year. Traffic increases on other roads and during other years when shipments could occur would be smaller. No traffic-related impacts are expected. LOS ratings would not change for any evaluated road. No noticeable increase in ESALs would occur on the evaluated roads between SSFL and major highways, with no damage to road pavement. Groundwater Treatment Shipment of radioactive waste – truck option a Shipments – 130 truck shipments Incident-free risks: - Crew LCFs: 0 (6×10-6 to 1×10-5) - Population LCFs: 0 (2×10-6 to 4×10-6) Accident risks: - Population LCFs: 0 (7×10-12 to 8×10-11) - Traffic fatalities: 0 (8×10-4 to 5×10-3 ) Shipment of radioactive waste – truck/rail option a Shipments – 130 truck shipments from SSFL to an intermodal facility, then 10 rail shipments Incident-free risks: - Crew LCFs: 0 (2×10-6 to 3×10-6) - Population LCFs: 0 (2×10-6 to 3×10-6) Accident risks: - Population LCFs: 0 (5×10-12) - Traffic fatalities: 0 (4×10-3) Shipment of nonradioactive waste, backfill, equipment, and supplies a Truck option: - 420 truck shipments - Traffic fatality risks: 0 (0.015) Truck/rail option: Not applicable. All shipments are by truck. The weekday average daily traffic on Woolsey Canyon Road would increase by 0.36 percent during 1 year. Traffic increases on other roads and during other years when shipments could occur would be smaller. No traffic-related impacts are expected. LOS ratings would not change for any evaluated road. Truck traffic would impose about 990 ESALs on the evaluated roads between SSFL and major highways, with minimal potential for damage to road pavement. Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory S-66 Resource Area Resource Area Human health Groundwater No Action Alternatives Groundwater Monitored Natural Attenuation Worker Worker There would be no impacts on workers Same as the Groundwater No Action Alternative. solely attributable to continuation of the current groundwater monitoring program; workers could receive a radiation dose from buildings and soil from monitoring and maintenance activities. Groundwater Treatment Worker Workers would receive a radiation dose from excavation of contaminated bedrock. Individual worker - Dose: 130 millirem - Project LCF risk: 1 in 100,000 Worker population - Total Dose: 0.7 person-rem - Project LCFs: 0 (5×10-5) Workers would be protected from industrial hazards and radiation exposure through compliance with DOE requirements for worker safety and radiation protection. Members of the public Same as the Groundwater No Action Alternative. Members of the public Same as the Groundwater No Action Alternative. Nonhazardous waste – 10 cubic yards Well development water – 5,000 gallons Monitoring purge water – 250 gallons/year LLW/MLLW – 1,700 cubic yards c Hazardous waste – 26 cubic yards c Summary Waste management Members of the public No impacts on a hypothetical future onsite suburban resident or recreational user are expected because groundwater wells do not produce sufficient water for residential use, and well water use by a recreational user is not expected. Considering the slow movement of Area IV groundwater and the concentrations of chemicals and radionuclides, no impacts on offsite members of the public are expected because groundwater migration is not expected to reach offsite receptors prior to decay below screening levels. No impacts are expected on the capacity of the permitted wastewater treatment plant that would receive approximately 250 gallons of purge water annually from Area IV. No exceedance of total waste capacity or a daily or annual waste No exceedance of total waste capacity or a daily or annual acceptance limit is expected at any evaluated facility. waste acceptance limit is expected at any evaluated facility. S-67 Cultural resources Groundwater No Action No archaeological or architectural cultural resources would be affected. No adverse impacts on traditional cultural resources are expected. Socioeconomics No socioeconomic impacts on employment, regional truck traffic, infrastructure and municipal services, housing, and local government revenue are expected in Los Angeles and Ventura Counties. No socioeconomic impacts on businesses in the vicinities of the offsite waste management facilities are expected. Environmental No impacts on the health of members justice of the public are expected. There would be no increases in traffic above baseline conditions in the SSFL and regional ROIs, and thus, no additional traffic-related impacts. No disproportionate impacts on Native American tribes and minority and lowincome populations are expected in the SSFL ROI or regional ROIs. Alternatives Groundwater Monitored Natural Attenuation Archaeological and architectural cultural resources likely would not be affected. Regarding traditional cultural resources, changes to setting are possible from installation of five additional monitoring wells. Minimal beneficial socioeconomic impacts from worker employment and purchases of equipment and supplies. There would be no socioeconomic impacts on businesses in the SSFL vicinity and no damage to pavement from additional traffic that could increase expenses for local governments. Groundwater Treatment Archaeological and architectural cultural resources likely would not be affected. Regarding traditional cultural resources, changes to setting are possible during installation and operation of groundwater treatment systems and strontium-90 source removal. Minimal beneficial socioeconomic impacts from worker employment and purchases of equipment and supplies. There would be no socioeconomic impacts on businesses in the SSFL vicinity and minimal damage to pavement from additional traffic that could increase expenses for local governments. - No impacts on the health of members of the public are - No impacts on the health of members of the public are expected. expected. Therefore, no disproportionately high and Therefore, no disproportionately high and adverse impacts on adverse impacts on Native American tribes and Native American tribes and minority and low-income populations minority and low-income populations in the SSFL ROI in the SSFL ROI are expected. are expected. - The increase in average daily traffic on the evaluated roads in the - Because the increase in average daily traffic on the SSFL vicinity would be slightly greater than that under the evaluated roads in the SSFL vicinity is very small (much Groundwater Monitored Natural Attenuation Alternative, but the less than 1 percent), no traffic impacts are expected. peak-year increase would still average less than 1 percent, with no No disproportionately high and adverse impacts on expected traffic impacts. Therefore, no disproportionately high and Native American tribes and minority and low-income adverse impacts on Native American tribes and minority and lowpopulations in the SSFL ROI are expected. income populations in the SSFL ROI are expected. - There would be no noticeable increase in truck traffic in - There would be no noticeable increase in truck traffic in the vicinity the vicinity of any facility receiving waste under this of any facility receiving waste under this alternative, with no alternative, with no expected traffic impacts. No expected traffic impacts. No disproportionately high and adverse disproportionately high and adverse impacts on Native impacts are expected on Native American tribes and minority and American tribes and minority and low-income low-income populations in the regional ROIs. populations in the regional ROIs are expected. Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory S-68 Resource Area Resource Area Groundwater No Action Alternatives Groundwater Monitored Natural Attenuation Groundwater Treatment Sensitive-aged populations Summary There would be no increases in traffic - Because the increase in average daily traffic on the - The increase in average daily traffic on the evaluated roads would above baseline conditions in the SSFL evaluated roads is very small (much less than 1 percent), be slightly greater than that under the Groundwater Monitored ROI and the regional ROIs, and thus, no disparate impacts are expected on sensitive-aged Natural Attenuation Alternative, but the peak-year increase in no additional traffic-related impacts. populations in the SSFL ROI. average daily traffic would still be less than 1 percent. No disparate No disparate impacts (markedly distinct - There would be no noticeable increase in truck traffic in impacts are expected on sensitive-aged populations in the SSFL impacts relative to those on the general the vicinities of disposal facilities, with no disparate ROI. population) on sensitive-aged impacts expected on sensitive-aged populations in the - There would be no noticeable increase in truck traffic in the vicinity populations are expected. regional ROIs. of any facility receiving waste under this alternative, with no disparate impacts expected on sensitive-aged populations in the regional ROIs. AOC = Administrative Order on Consent for Remediation; BMP = best management practice; CNEL = community noise equivalent level; CO = carbon monoxide; CO2 = carbon dioxide; CMWD = Calleguas Municipal Water District; dBA = decibels A-weighted; ESAL = equivalent single-axle load; LCF = latent cancer fatality; LLW = low-level radioactive waste; LOS = level of service; LUT = Look-Up Table; MLLW = mixed low-level radioactive waste; NBZ = Northern Buffer Zone; NOX = nitrogen oxide; RMHF = Radioactive Materials Handling Facility; ROI = region of influence; SO2 = sulfur dioxide; VOC = volatile organic compound. a Transportation risk results are presented as whole numbers with the actual calculated values presented in parentheses. Values in parentheses that have a negative power of 10 are less than 1. The larger the negative value of 10, the smaller the number. b Wastes generated under the Groundwater Monitored Natural Attenuation Alternative consist of very small quantities of cuttings from monitoring well installation and water from well installation and sampling that are shipped by truck only. These wastes are not expected to be classified as low-level or mixed low-level radioactive waste, but if determined otherwise when generated, would be safely transported to appropriate authorized or permitted facilities for disposition. c These volumes reflect conservative estimates of waste generation considering the range of groundwater treatment technologies that may be implemented in the future. S-69 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory S.11.2 Potential Environmental Consequences of Combined Action Alternatives This section addresses potential impacts for each resource area, assuming (1) implementation of six possible combinations of action alternatives, as summarized in the text box below, and (2) each combination includes one soil remediation action alternative, one building demolition action alternative, and one groundwater remediation action alternative (also see below). Action Alternative Combination Designation Cleanup to AOC LUT Values + Building Removal + Groundwater Monitored Natural Attenuation Cleanup to AOC LUT Values + Building Removal + Groundwater Treatment – Action Alternative Combination with the Largest Environmental Consequences (High Impact Combination) Cleanup to Revised LUT Values + Building Removal + Groundwater Monitored Natural Attenuation – Cleanup to Revised LUT Values + Building Removal + Groundwater Treatment – Conservation of Natural Resources + Building Removal + Groundwater Monitored Natural Attenuation Action Alternative Combination with the Smallest Environmental Consequences (Low Impact Combination) Conservation of Natural Resources + Building Removal + Groundwater Treatment – AOC = Administrative Order on Consent for Remedial Action; LUT = Look-Up Table. For most resource areas, the largest potential impacts (e.g., most waste generated, most truck round trips) are associated with the combination of the Cleanup to AOC LUT Values, Building Removal, and Groundwater Treatment Alternatives. This combination of action alternatives is termed the “High Impact Combination.” Conversely, for most resource areas, the smallest impacts are associated with the combination of the Conservation of Natural Resources, Building Removal, and Groundwater Monitored Natural Attenuation Alternatives. This combination of action alternatives is termed the “Low Impact Combination.” To avoid repetition, these terms are used as a shorthand way to refer to the above combinations of action alternatives. However, for those resource areas where the impacts to be addressed are not necessarily encompassed by these combinations of action alternatives, the applicable combination was specified and evaluated. The suite of groundwater treatment technologies to be implemented would be determined independently from this EIS by means of a RCRA Corrective Measures Study (see Chapter 2, Section 2.6). Because the results of this Corrective Measures Study are yet to be determined, this EIS evaluates the potential impacts that could occur during groundwater remediation activities, assuming the implementation of those technologies planned for inclusion in the Corrective Measure Study that would result in the largest potential impacts. In addition, DOE could decide to implement elements of both groundwater remediation action alternatives rather than one alternative or the other. In this event, the potential impacts for some resource areas could be slightly larger than those under the High Impact Combination (which includes potential impacts from the Groundwater Treatment Alternative, but not the Groundwater Monitored Natural Attenuation S-70 Summary Alternative). These potential incremental impacts are addressed as appropriate in the following subsections. Land resources. Land resources were evaluated for land use at Area IV and the NBZ, access to recreation areas in the SSFL region of influence (ROI), Area IV infrastructure, and Area IV and the NBZ aesthetics and visual quality. Land use. No combination of action alternatives would cause a change in land use designation; after remediation, Area IV and the NBZ would be compatible with the landowner’s (Boeing’s) intent to maintain its land as undeveloped open space (Boeing 2016b). Recreation. The High Impact Combination would result in average daily heavy-duty truck round trips ranging over 12 years from about 8 to 48. The weekday average daily traffic on Woolsey Canyon Road would conservatively increase by 3.4 to 5.3 percent during the first 2 years, by 7.3 percent to 7.6 percent during the next 9 years, and by 5.6 percent during the final year. There would be smaller increases in traffic on other evaluated roads. Traffic would not be noticeably increased if both groundwater remediation action alternatives were implemented. The Low Impact Combination would result in heavy-duty truck traffic that would primarily occur over 4 years. The average daily truck trips during these years would range from about 8 to 47, and the average daily traffic on Woolsey Canyon Road would increase by 3.5 to 7.4 percent. There would be smaller increases in traffic on other evaluated roads. There would be minor increases in average daily traffic in subsequent years (e.g., less than 0.1 percent on Woolsey Canyon Road), primarily due to shipments of monitoring well purge water and environmental monitoring samples. Under all action alternative combinations, motorists could experience or perceive delays in using Woolsey Canyon Road to access Sage Ranch Park, which could reduce its weekday use during the years of site remediation. Increased traffic, however, would occur for about three times as many years under the High Impact Combination as those under the Low Impact Combination. Except for Woolsey Canyon Road, traffic on any evaluated road that may pass a recreation area in the SSFL vicinity could be reduced by distributing truck traffic among the four evaluated routes between SSFL and major highways. Infrastructure. Annual electrical requirements would be minimal under all combinations of action alternatives. CMWD is the expected source for water for remediation activities such as dust suppression. Over 12 years, about 41 million gallons of water would be used under the High Impact Combination. The maximum annual water use would be about 4.0 million gallons, representing about 0.007 percent of CMWD’s current imported and local water supply. If both groundwater remediation action alternatives were implemented, both the maximum annual and total water use would increase by about 5,000 gallons. Over 4 years, about 8.6 million gallons of water would be used under the Low Impact Combination. The maximum annual water use would be about 4.0 million gallons, again representing about 0.007 percent of CMWD’s combined imported and local water supply. Under any combination of action alternatives, water use is important because of California’s current drought conditions and Governor Brown’s Executive Order requiring a statewide 25 percent reduction in potable water use (CA EO 2015). Water use may be potentially reduced through measures such as using surfactants to assist in dust control. Aesthetics and visual quality. Over all combinations of action alternatives, all DOE-owned buildings and considerable quantities of soil would be removed. Soil would be backfilled on excavated areas and re-graded and re-contoured as necessary, and disturbed areas would be stabilized and revegetated. During remediation operations, onsite views at Area IV and the NBZ would be S-71 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory degraded. In the long term, stabilization and revegetation of affected areas would introduce a new surface texture and color in areas that were previously barren and improve onsite aesthetics and visual quality. Geology and soils. Excavation of 1,050 cubic yards of subsurface bedrock was assumed under action alternative combinations that include the Groundwater Treatment Alternative (such as the High Impact Combination). Excavation of this bedrock would have minimal potential adverse impacts on bedrock geologic resources. Under any combination of action alternatives, there would be minimal potential impacts on paleontological resources (i.e., loss of fossils) because the Santa Susana Formation where these resources largely occur is mostly located within the proposed exemption areas. Nonetheless, potential impacts on paleontological resources would likely be largest under action alternative combinations that include the Cleanup to AOC LUT Values Alternative and smallest for action alternative combinations that include the Conservation of Natural Resources Alternative. Outside of the proposed exemption areas, about 1 acre of land containing chemical or radioactive constituents exceeding AOC LUT values overlies the Santa Susana Formation, but less than 0.1 acre of land containing chemical (but no radioactive) constituents exceeding risk-assessment-based values overlies the Santa Susana Formation. There could be risks to workers remediating soil in some locations at Area IV and the NBZ that are within zones where earthquake-induced landslides could occur. Buildings are not in areas of landslide risk, but bedrock assumed to be removed under the Groundwater Treatment Alternative is on the edge of a geologic hazard zone. Potential risks to workers from landslides would be largest under the High Impact Combination and smallest under the Low Impact Combination (because of the lesser extent of soil remediation and no bedrock removal). DOE would minimize risks to workers by implementing the 2010 AOC (DTSC 2010a) exemption process for certain areas if, during the planning and design of soil remediation activities, it was determined that excavating soil in these areas would present unacceptable risks. Seismic shaking can also pose a risk to workers removing buildings. Risks to workers due to proximity to structures that could collapse due to seismic shaking would be the same under all action alternative combinations. These risks would not be affected if DOE implemented both groundwater remediation action alternatives. About 138 acres of land outside the proposed exemption areas would be disturbed under the High Impact Combination, while about 40 acres outside the proposed exemption areas would be disturbed under the Low Impact Combination. Disturbed land would primarily include areas where buildings and pavement are removed and soil is remediated. Although potential impacts from soil erosion would be minimized using BMPs, as summarized in Chapter 6, rainstorms could result in soil erosion, leading to a reduction of soil quality and functional capability within eroded areas. About 715,000 cubic yards of backfill from offsite sources may be required under the High Impact Combination. The quality of this backfill for biological activity, filtration, and vegetation support may be less than that of current soil at Area IV and the NBZ, in which case the backfill would be less able to support growth of vegetation similar to that present before development of Area IV. Sources for this large quantity of backfill, containing chemical and radioactive constituents in concentrations less than AOC LUT values and of comparable quality, have not been located, and it appears unlikely that a source of backfill meeting chemical AOC LUT values can be found (see Section S.10.2.2). As noted in Section S.10.2.2, if a source of backfill that meets all of the AOC LUT values cannot be reasonably found, then DTSC, DOE, and EPA would enter into a consultation process, and DTSC would determine the best available source of backfill (DTSC 2010a). S-72 Summary About 125,000 cubic yards of backfill from offsite sources may be required under the Low Impact Combination. This backfill would need to be of comparable quality to that of current soil at Area IV and the NBZ and contain chemical and radioactive constituents in concentrations that meet risk-assessment-based values. DOE has not identified and evaluated potential sources of backfill to determine whether it would meet constituent concentration values consistent with risk-assessmentbased values. However, because the allowable constituent concentrations in backfill under this combination of action alternatives would generally be higher than AOC LUT values, DOE expects that finding acceptable sources of backfill would be more likely. Surface water resources. The High Impact Combination would have the greatest potential for impacts on surface water, primarily because of the large area of disturbed land (138 acres). The Low Impact Combination would have the smallest potential for impacts on surface water because it would have the least soil disturbance (40 acres) and would result in the least potential for soil erosion that could increase sediment levels in runoff. The Groundwater Monitored Natural Attenuation Alternative would have less potential for soil erosion than the Groundwater Treatment Alternative because it would disturb less soil that is currently shielded from erosion by vegetation when compared to the excavation and earthmoving actions required under the Groundwater Treatment Alternative. If DOE implemented both groundwater remediation action alternatives, the potential for soil disturbance would be essentially the same as that from implementing the Groundwater Treatment Alternative alone. Under any combination of action alternatives, the BMPs and minimization measures described in Chapter 6 would be implemented to filter sediments and other contaminants from surface water runoff and limit increases in runoff velocity and volume. Except possibly for scenarios where an unusually large rainstorm occurs in the interval between soil excavation and revegetation of disturbed areas, coupled with exceedance of the stormwater control system capacity, no impacts are expected on surface water quality on site and in regional waterways or on SSFL or regional stormwater control capacities. To forestall the risks of potential impacts under these scenarios, DOE would evaluate mitigation measures; these measures could including requiring that, in areas excavated to bedrock, excavation and backfill activities be completed prior to or following the typical rainfall of December through May. DOE would also construct additional stormwater retention structures (such as catch basins or retention basins) and/or implement additional erosion control measures if runoff studies indicate the NPDES stormwater control system design capacity would be exceeded. Implementing any combination of action alternatives would result in a long-term improvement in surface water resources at Area IV and its vicinity because a potential source of surface water contamination would be removed. Groundwater resources. The combination of action alternatives with the largest positive impact on groundwater quality, in the shortest time frame, would be the High Impact Combination. Nearly all of the positive impact would result from implementation of the Groundwater Treatment Alternative. Although the Building Removal Alternative would be considered under all combinations of action alternatives, the Area IV buildings are not a source of chemicals or radionuclides to groundwater. Although the Cleanup to AOC LUT Values Alternative would remove more chemical constituents in soil than the Cleanup to Revised LUT Values or Conservation of Natural Resources Alternative, and the Cleanup to AOC LUT Values and Cleanup to Revised LUT Values Alternatives would remove more radioactive constituents in soil than the Conservation of Natural Resources Alternative, there would be little difference expected among the soil removal action alternatives in terms of potential positive impacts on groundwater. The added benefit to groundwater cleanup from soil removal is relatively low because the most highly impacted S-73 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory soil has already been removed. There would be no adverse impacts on groundwater from soil removal. The Low Impact Combination would have a comparable positive impact on groundwater quality, but this positive impact would be achieved over a much longer time frame. If both groundwater remediation action alternatives were implemented, the advantageous features of monitored natural attenuation would be combined with other technologies employing active measures to remediate groundwater. The source of the water used for site remediation activities is expected to be CMWD. Biological resources. The High Impact Combination would have the largest overall potential impacts. Although the soil remediation action alternatives would each have substantial potential impacts on biological resources, the largest would occur under the Cleanup to AOC LUT Values Alternative. Vegetation and wildlife habitat and soil would be removed from about 130 acres of land outside the proposed exemption areas, including about 51 acres of relatively undisturbed native habitat, including coast live oak woodland, northern mixed chaparral, and Venturan coastal scrub. This activity would cause profound disturbance to affected areas and require a substantial, focused, and prolonged effort to achieve revegetation and restoration of habitat, including replacement of removed soil with soil similar in parent material, texture, and nutrient status; collection and propagation of native plants, including oaks and shrubs; and several years of maintenance, weed control, and monitoring until the vegetation is self-sustaining. Building removal would occur in previously disturbed habitats with low to moderate potential impacts on biological resources. Native species of birds and bats that roost or nest in the buildings would lose these sites when the buildings are removed. However, direct impacts on nesting or roosting species could be avoided or minimized through a combination of seasonal timing of demolition activities to avoid seasons when nesting is occurring, humane hazing of individuals using the buildings prior to demolition (e.g., by human activity in proximity to perching birds, inducing them to leave), and measures to prevent their reentry until demolition is complete. If listed species such as Santa Susana tarplant are established in proximity to buildings, direct impacts could be minimized by surveys and avoidance where possible. (No other sensitive plant species are expected in the approximately 8.4 acres of highly disturbed habitat adjacent to the buildings to be removed.) Unavoidable impacts on individual tarplants could be mitigated by salvage of seed, propagation, and replanting as part of restoration activities following demolition. Compared to the Groundwater Monitored Natural Attenuation Alternative, there would be greater surface disturbance under the Groundwater Treatment Alternative through the assumed emplacement and operation of treatment units and excavation of subsurface bedrock; however, potential impacts on threatened, endangered, or rare species would likely be avoidable due to the localized nature of the activities, the small areas affected, and the proximity of well sites to existing access roads and disturbed areas. If both groundwater remediation action alternatives were implemented, surface disturbance would be essentially the same as that under the Groundwater Treatment Alternative alone. The Low Impact Combination would have the smallest overall potential impacts. The Conservation of Natural Resources Alternative would remove vegetation and wildlife habitat from about 32 acres outside the proposed exemption areas, which is about 25 percent of the disturbed acreage under the Cleanup to AOC LUT Values Alternative and 8 acres less than the disturbed acreage under the Cleanup to Revised LUT Values Alternative. The Conservation of Natural Resources Alternative would have far fewer impacts on vegetation and wildlife habitat and biota, wetland and aquatic habitats and biota, and threatened, endangered, or rare species than the Cleanup to AOC LUT Values Alternative, and also fewer potential impacts than the Cleanup to Revised LUT Values Alternative. Potential impacts under the Building Removal Alternative have been summarized S-74 Summary above. Impacts on these resources under the Groundwater Monitored Natural Attenuation Alternative would be smaller than those under the Groundwater Treatment Alternative, but either groundwater action alternative would have comparatively low impacts on biological resources, and the differences between the groundwater action alternatives in terms of biological impacts are modest. Air quality and climate. The air quality analysis evaluated three combinations of action alternatives that would result in the highest potential impacts: (1) the Cleanup to AOC LUT Values, Building Removal, and Groundwater Treatment Alternatives; (2) the Cleanup to Revised LUT Values, Building Removal, and Groundwater Treatment Alternatives; and (3) the Conservation of Natural Resources, Building Removal, and Groundwater Treatment Alternatives. Emissions under the Groundwater Monitored Natural Attenuation Alternative were not quantitatively estimated because this alternative would generate very low emissions, and the Groundwater Treatment Alternative represents worse-case emissions for either groundwater remediation action alternative. Emissions presented in this section for the three combinations of action alternatives would be slightly smaller if the Groundwater Monitored Natural Attenuation Alternative were implemented under any action alternative combination, and slightly larger if both groundwater remediation action alternatives were implemented.30 Projected emissions were evaluated relative to air quality conditions within three air domains and their applicable Federal, state, and local air pollution standards and regulations. These domains are:  Ventura County and the area directly adjacent to SSFL, which are within the South Central Coast Air Basin;  South Coast Air Basin, which includes portions of Los Angeles County; and  regions beyond Ventura County and the South Coast Air Basin, spanning several air basins and jurisdictional agencies. For criteria pollutants where an evaluated domain is in attainment of the National Ambient Air Quality Standards (NAAQS), annual emissions were compared to the EPA Prevention of Significant Deterioration threshold for new major sources (250 tons per year of a pollutant) as an indicator of the magnitude of projected potential air quality impacts. For criteria pollutants where an ROI does not attain or is in maintenance of a NAAQS, annual emissions were compared to the applicable pollutant threshold that requires a conformity determination for that region. For example, because Ventura County attains the NAAQS for all pollutants except ozone, emissions from proposed activities within this ROI were compared to the following annual emission thresholds: (1) 50 tons of volatile organic compounds (VOCs) and nitrogen oxides (NOX); and (2) 250 tons of carbon monoxide, sulfur dioxide (SO2), particulate matter less than 2.5 microns in diameter (PM2.5), and particulate matter less than 10 microns in diameter (PM10). If emissions were determined to potentially exceed an EPA Prevention of Significant Deterioration or conformity threshold, further analysis was conducted to determine whether they would contribute to exceedance of an ambient air quality standard or conform to the approved State Implementation Plan. The term, “High Impact Combination,” is not used in this subsection because the largest potential impacts are not necessarily encompassed by the combination of the Cleanup to AOC LUT Values, Building Removal, and Groundwater Treatment Alternatives. This is primarily because the main focus of the air impacts analysis is on comparison of emissions against annual emission thresholds and daily ambient air quality standards rather than total emissions. The term, “Low Impact Combination,” is not used because the potential impacts from the Groundwater Monitored Natural Attenuation Alternative are negligibly small and are not addressed. Rather, the appropriate action alternative combinations are specified and evaluated. Three potential action alternative combinations are addressed to ensure comparison of the ranges in emissions from these combinations against the annual thresholds and daily standards. 30 S-75 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Estimates were made of peak annual and peak daily emissions. Peak annual emissions from the combinations of action alternatives were compared to annual indicator emission thresholds for the three evaluated domains, whereas peak daily emissions were used to indicate the potential for an action alternative combination to contribute to an exceedance of an ambient air quality standard. The thresholds assumed for the air domain outside of Ventura County and the South Coast Air Basin include ranges of values that encompass air quality conditions within all regions traversed by the proposed truck trips. Ventura County. Peak annual emissions under all three evaluated combinations of action alternatives would be well below the indicator emissions thresholds identified for Ventura County. There is also little difference in peak annual and peak daily emissions for the three evaluated combinations of action alternatives. For example, the ranges in annual emissions vary by no more than about 7 percent for VOCs, carbon monoxide, NOX, and SO2 across the three evaluated combinations of action alternatives, by 35 percent for PM10, and by 9 percent for PM2.5. The projected elevated levels of PM10 emissions primarily result from fugitive dust from operation of equipment and trucks on unpaved surfaces and trucks on paved roads internal to SSFL. DOE would implement measures to control fugitive dust emissions (PM10 and PM2.5) from the proposed activities, including measures to comply with Ventura County Air Pollution Control District Rule 55 (Fugitive Dust), which restricts emissions of fugitive dust from being visible beyond the property line of a source. Therefore, these controls and restrictions would ensure that emissions of fugitive dust from the combined action alternatives would not contribute to an exceedance of a PM10 ambient air quality standard at any offsite location. South Coast Air Basin. For the South Coast Air Basin, the ranges in peak annual and daily emissions for the three evaluated combinations of action alternatives would be somewhat larger than those for the Ventura County ROI, but nonetheless reflect only minor differences in projected emissions. For example, considering both the nearby and distant disposal scenarios, the ranges in annual emissions vary by no more than about a factor of 2 for VOCs, carbon monoxide, NOX, and SO2 across the three combinations of action alternatives, by 57 percent for PM10, and by 50 percent for PM2.5. None of the annual emissions would exceed the South Coast Air Basin indicator emission thresholds, except for NOX under the distant disposal site scenario. These emissions would occur intermittently from an average of up to 48 daily truck round trips and would extend over several miles of roads across the South Coast Air Basin. As a result, these emissions would be diluted in the atmosphere to the point that they would produce minimal ambient impacts in a localized area and would not contribute to an exceedance of an ambient air quality standard. For this same reason, these combined action alternatives also would produce minimal ambient impacts of hazardous air pollutants and toxic air contaminants within the South Coast Air Basin. Outside Ventura County and the South Coast Air Basin. To define the worst-case indicator emission thresholds for the regions outside of Ventura County and the South Coast Air Basin, the most degraded air quality conditions were assumed for any area where trucks would travel between SSFL and offsite disposal facilities. Hence, the worst-case air quality conditions for the regions traversed by trucks to nearby (Buttonwillow site) and distant (NNSS or US Ecology in Idaho) disposal sites occur within the San Joaquin Valley Air Basin and the Mojave Desert Air Basin. For two of the three combinations of action alternatives (the Cleanup to Revised LUT Values, Building Removal, and Groundwater Treatment Alternatives and the Conservation of Natural Resources, Building Removal, and Groundwater Treatment Alternatives), peak annual emissions generated by truck travel between SSFL and the disposal facility locations would exceed these worst-case NOX emission thresholds. However, truck mileages driven solely within the San Joaquin Valley Air Basin and Mojave Desert Air Basin would produce emissions that would remain below their applicable NOX S-76 Summary emission thresholds. Trucks driven within all other air basins also would produce emissions that would remain below their applicable NOX emission thresholds. Although relatively high levels of daily NOX emissions were estimated for regions outside Ventura County and the South Coast Air Basin, these emissions would occur intermittently from an average of up to 48 daily haul truck round trips and would extend over hundreds of miles of roadways. As a result, these emissions would be diluted in the atmosphere to the point that they would produce minimal ambient impacts in a localized area and would not contribute to an exceedance of an ambient air quality standard. For this same reason, minimal ambient impacts of hazardous air pollutants and toxic air contaminants are expected outside of Ventura County and the South Coast Air Basin. Green cleanup. The above discussion addresses calculated impacts assuming use of California average off-road and on-road vehicle fleets for calendar year 2019. Implementing equipment that meets EPA Nonroad Tier 3 and 4 emission standards and new trucks that meet the most recent EPA onroad standards would reduce these potential impacts (see Chapter 6, Mitigation Measure AQ-1). In the Ventura County domain, emissions from the average year 2019 fleet, as averaged over all air pollutants, would be reduced by 21 percent for off-road equipment that meets EPA Nonroad Tier 3 standards, and 58 percent for on-road heavy-duty trucks. In the South Coast Air Basin and the evaluated domain outside Ventura County and the South Coast Air Basin, emissions from the average year 2019 fleet, as averaged over all air pollutants, would be reduced by 61 percent. Therefore, implementing the proposed green cleanup fleets would produce substantial emission reductions compared to use of California average fleets. Climate change. Peak annual emissions of CO2 would range from about 3,000 to 8,900 metric tons under the combination of the Cleanup to AOC LUT Values, Building Removal, and Groundwater Treatment Alternatives; 6,000 to 17,000 metric tons under the combination of the Cleanup to Revised LUT Values, Building Removal, and Groundwater Treatment Alternatives; or 6,100 to 17,000 metric tons under the combination of the Conservation of Natural Resources, Building Removal, and Groundwater Treatment Alternatives. Total emissions of CO2 would range from about 30,000 to 89,000 metric tons under the combination of the Cleanup to AOC LUT Values, Building Removal, and Groundwater Treatment Alternatives; 14,000 to 37,000 metric tons under the combination of the Cleanup to Revised LUT Values, Building Removal, and Groundwater Treatment Alternatives; or 9,700 to 29,000 metric tons under the combination of the Conservation of Natural Resources, Building Removal, and Groundwater Treatment Alternatives. Emissions under each combination of action alternatives would be slightly smaller if the Groundwater Monitored Natural Attenuation Alternative was implemented and slightly larger if both groundwater action alternatives were implemented. Climate change could impact implementation of the alternatives and the adaptation strategies needed to respond to future conditions. Within Ventura County, the main effect of climate change is increased temperature and aridity. Analyses predict that, in the future, the region will experience: (1) an increase in temperatures, droughts, and wildfires; and (2) and scarcities of water supplies (California Energy Commission 2012; IPCC 2013; USGCRP 2014). Current operations at SSFL have adapted to droughts, high temperatures, wildfires, and scarce water supplies; however, future exacerbation of these conditions could impede proposed activities during extreme events. Noise. There would be little difference in the intensity of noise emanating from Area IV for any combination of action alternatives. All combinations would require use of heavy equipment, and similar noise intensities would be experienced at the nearest residence, with no expected noise impacts. In addition, all combinations would entail up to 48 average daily heavy-duty truck round trips, with possible occasional spikes to 96 round trips. Over the entire range of daily truck round S-77 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory trips, time-averaged noise levels in residential areas would increase by no more than 3.5 decibels A-weighted (dBA) community noise equivalent level (CNEL) along all roads where noise would remain below 65 dBA CNEL and would increase by no more than 0.6 dBA CNEL along the road where noise levels would exceed 65 dBA CNEL (one section of Valley Circle Boulevard already exceeds 65 dBA CNEL). Although the increased traffic would be audible to persons in the vicinities of the evaluated roads, the increased noise would not be expected to exceed “normally acceptable” levels and would not exceed the adverse impact thresholds per the L.A. CEQA Thresholds Guide, Your Resource for Preparing CEQA Analyses in Los Angeles (LA 2006). The combination of action alternatives having the longest noise duration (12 years) would be the High Impact Combination, primarily because of the volume of soil removed. There would be no change in noise duration if both groundwater remediation action alternatives were implemented. The combination of action alternatives having the shortest noise duration would be the Low Impact Combination. Because much less soil would be removed, almost all remediation activities under this combination of action alternatives would be completed in 4 years. After that, there would be very minor traffic noise, primarily from transport of monitoring well purge water for offsite disposition and monitoring samples to offsite laboratories. Transportation. Maximum risks of transporting radioactive waste to the evaluated disposal facilities would occur under the High Impact Combination or the combination of the Cleanup to Revised LUT Values, Building Removal, and Groundwater Treatment Alternatives. For incidentfree transport and assuming all radioactive waste shipments were by truck, maximum latent cancer fatality (LCF) risks to truck crews and the population would occur for shipment to EnergySolutions in Utah. The risk of a single LCF among the truck crews or in the population would be 9  10-4 (1 chance in 1,100) and 2  10-4 (1 chance in 5,000), respectively. If shipments were made using the truck/rail option, the maximum risk of a single LCF among the truck/rail crews would be 3  10-4 (1 chance in 3,300) for shipment to NNSS. The maximum truck/rail option risk of a single LCF in the population would be 2  10-4 (1 chance in 5,000) for shipment to EnergySolutions in Utah. The risk of a single LCF from an accident, considering all possible accidents from minor to severe, would be 5  10-9 (1 chance in 200 million), assuming all shipments were by truck to EnergySolutions or 3  10-10 (1 chance in 3.3 billion) by the truck/rail option to either evaluated facility. Minimum risks would occur under the Low Impact Combination. For incident-free transport and assuming all radioactive waste shipments were by truck, maximum LCF risks to truck crews and the population would occur for shipment to EnergySolutions in Utah. The risk of a single LCF among the truck crews or in the population would be 5  10-4 (1 chance in 2,000) and 1  10-4 (1 chance in 10,000), respectively. If shipments were made using the truck/rail option, the maximum risk of a single LCF among the truck/rail crews would be 2  10-4 (1 chance in 5,000) for shipment to NNSS. The maximum truck/rail option risk of a single LCF occurring in the population would be 9  10-5 (1 chance in 11,000) for shipments to EnergySolutions. The maximum risk of a single LCF from an accident, considering all possible accidents from minor to severe, would be 3  10-9 (1 chance in 330 million), assuming all shipments were sent by truck to NNSS or 2  10-10 (1 chance in 5 billion) by the truck/rail option to either evaluated facility. The largest traffic accident risks from transporting all radioactive waste, all nonradioactive waste, and all material (backfill, equipment, and supplies) would occur under the High Impact Combination. Under the truck option, considering shipment of all radioactive and nonradioactive waste and material, the number of traffic-related fatalities is estimated to be about 1 (calculated value of 0.84). Under the truck/rail option, the number of transportation-related fatalities is estimated to be about 3 (calculated value of 2.9). The smallest risks would occur under the Low Impact Combination. The number of fatalities that estimated to result from transporting all waste and S-78 Summary material is 0 (calculated maximum value of 0.45) under the truck option and 0 (calculated value of 0.42) under the truck/rail option. Traffic. Under the High Impact Combination, there would be about 119,000 heavy- and mediumduty truck round trips. In addition, there would be about 68,600 round trips of cars or light-duty trucks, primarily for worker commutes. The largest increase in traffic would occur on Woolsey Canyon Road. Over 12 years, the weekly average daily traffic volume would increase by 3.4 to 7.6 percent. During most of these years, the level of service (LOS) for Woolsey Canyon Road could change from a B rating to a C rating. Motorists on Woolsey Canyon Road during weekdays when heavy-duty trucks would be traveling to or from SSFL could experience delays compared to baseline conditions; there could also be delays at the intersection of Woolsey Canyon Road with Valley Circle Boulevard. The increased traffic could be reduced on roads other than Woolsey Canyon Road by distributing traffic among multiple routes between SSFL and major highways. Traffic associated with the High Impact Combination would impose about 210,000 equivalent single-axle loads (ESALs)31 on the roads on the evaluated routes between SSFL and major highways. These increases were determined assuming each evaluated route received all traffic. Because some of the evaluated roads already need repair, increased vehicle traffic could further damage the surrounding roads, causing them to need repair sooner than currently anticipated. If both groundwater remediation action alternatives were implemented, the number of heavy- and medium-duty truck round trips would increase during a 12-year period by about 42 round trips compared to the High Impact Combination estimate of 119,000 round trips. Thus, there would be no noticeable increase in traffic volumes or ESALs from those analyzed under the High Impact Combination. Under the Low Impact Combination, there would be about 20,800 heavy- and medium-duty truck round trips. In addition, there would be about 20,800 round trips of cars or light-duty trucks, generally from worker commutes. The largest increase in traffic would occur on Woolsey Canyon Road, where the weekly average daily traffic would increase by 3.5 to 7.4 percent during the first 4 years of this action alternative combination, with a change in LOS from a B rating to a C rating, similar to that under the High Impact Combination. Traffic increases for subsequent years would be about 0.092 percent, primarily due to shipments of well monitoring purge water and environmental samples and worker commutes. Traffic delays similar to those under the High Impact Combination could occur, except that the delays would last for 4 years rather than 12. The increased traffic could be reduced on roads other than Woolsey Canyon Road by distributing traffic among multiple routes between SSFL and major highways. Traffic associated with this combination of action alternatives would impose about 45,000 ESALs on the roads along the evaluated routes between SSFL and major highways, assuming each route received all traffic. Because some of the evaluated roads already need repair, this increase in vehicle traffic could further damage surrounding roads, causing them to need repair sooner than currently anticipated. A safety concern is noted: heavy-duty trucks making a sharp right turn from Woolsey Canyon Road onto Valley Circle Boulevard may need to pull partially into an adjacent lane, resulting in a risk of incidents with oncoming traffic. This risk would be applicable to all action alternatives, but particularly the soil remediation action alternatives and the Building Removal Alternative, and may be mitigated by measures such as installation of a traffic signal at the intersection or posting of a flag person when shipments are made from Area IV. 31 An ESAL is defined as the damage caused by a single 18,000-pound vehicle axle such as that found on a heavy-duty truck. S-79 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Human health. Following remediation of Area IV and the NBZ, the principal risk would be residual chemicals and radioactive material remaining in the soil. Following removal of DOE buildings under the Building Removal Alternative, there would be no remaining impact attributable to the buildings. Under the groundwater remediation action alternatives, neither near-term activities such as installing wells and removing the strontium-90 subsurface bedrock source nor the remaining activities such as monitoring or operating treatment equipment would result in chemical or radiation exposures to offsite members of the public. Consequently, the combined potential impacts would be dominated by the impacts associated with soil. The potential impacts on a hypothetical future onsite suburban resident following any of the soil action alternatives would be smaller than those under the No Action Alternative, which are very close to the potential impacts from background soil. The High Impact Combination, under which the most soil would be removed from the site, would be expected to have the lowest residual risk. The Low Impact Combination, under which soil with chemical and radionuclide concentrations meeting risk-assessment-based values would remain on site, would have a slightly higher residual risk. Implementing different combinations of action alternatives would have little effect on the maximum number of workers on site in a year, but would have a large effect on the number of years that workers could be exposed to chemical, radiological, and industrial hazards. Under the High Impact Combination, workers would be subject to hazards over about a 12-year period, while under the Low Impact Combination, workers would be subject to hazards for about a 4-year period. In addition, there could be a combined impact on workers involved in both building demolition (decontamination and decommissioning [D&D] workers) and soil or groundwater remediation (remediation workers). However, because the potential impacts on remediation workers are estimated to be significantly less than those for D&D workers, the combined impacts would not be significantly larger than those for D&D workers alone. Regardless of the combination of action alternatives, workers would be protected in accordance with DOE regulations (e.g., 10 CFR Parts 835 and 851) and orders. Worker protection practices would be employed so that doses are ALARA below DOE occupational exposure limits. Waste management. Over all combinations of action alternatives, the total LLW/mixed low-level radioactive waste (MLLW) volume would be up to 103,000 cubic yards, which would not impact the total waste disposal capacity at NNSS or EnergySolutions in Utah. There would be about 4,550 to 7,980 truck shipments from SSFL that would occur over 4 to 12 years, depending on the combination of action alternatives. Depending on the combination of action alternatives, the average daily number of offsite shipments would range from less than 1 to about 14. Under the truck option and assuming all waste was delivered to a single facility, there would be the same number of daily shipments arriving at that facility. There could be logistical concerns at a facility to ensure that personnel, equipment, and active disposal space are available for these deliveries plus deliveries from other waste generators. However, these concerns could be alleviated through careful scheduling and coordination with the disposal facility operators. Under the truck/rail option, there would be the same number of daily deliveries to NNSS, but reduced daily deliveries (all by rail) to EnergySolutions in Utah compared to those under the truck option. The total hazardous waste volume (49,100 cubic yards for all action alternative combinations) would not impact the total disposal capacity at any evaluated hazardous waste facility. There would be about 3,690 to 3,930 truck shipments from SSFL that would occur over 4 to 12 years, depending on the combination of action alternatives, with an average daily number of offsite shipments ranging from less than 1 to about 8. Average daily tonnages would range from less than 1 ton to about 150 tons. Under the truck option, there would be the same number of daily deliveries at any assumed single disposal facility. The projected shipments would not impact the daily or yearly receipt limit, if applicable, at any of the evaluated facilities. Under the truck/rail option, there would S-80 Summary be the same number of daily deliveries to the Buttonwillow or Westmorland facilities in California, because these facilities lack direct rail accessibility, but reduced daily shipments (all by rail) to US Ecology in Idaho. The total nonhazardous waste volume would range from about 53,200 to 794,000 cubic yards. The high end of the range would occur under any combination of action alternatives that includes the Cleanup to AOC LUT Values and Building Removal Alternatives; this volume of waste would represent about 48 percent of the capacity being constructed or planned at the McKittrick Waste Treatment Site in California (assuming all nonhazardous waste was sent to this site). There would be about 4,020 to 59,600 truck shipments from SSFL over 4 to 12 years, depending on the combination of action alternatives. Over this time, the average daily number of offsite shipments would range from less than 1 to about 25, and the average daily tonnage would range from about 1 ton to about 490 tons. Under the truck option, there would be the same number of daily deliveries to any of the evaluated facilities, assuming all waste was shipped to a single facility. The projected shipments would not exceed an annual or daily receipt limit at any of the evaluated facilities, but would represent 16 percent of the daily limit at the McKittrick Waste Treatment Site. Under the truck/rail option, waste would be shipped to the Mesquite Regional Landfill in California at a rate that would represent up to 2 percent of the site’s daily waste acceptance limit. About 3,540 cubic yards of recyclable material would be delivered to offsite recycle facilities over 2 years under all combinations of action alternatives. There would be less than two average shipments per day, assuming shipments occurred each year over a 5-month period, but less than one per day if the shipments were spread over a working year. There is adequate recycle capacity in the vicinity of SSFL, so no impacts on this capacity are expected. Therefore, no combination of action alternatives would generate waste that would lack disposal capacity. The evaluated facilities have adequate total capacities, and the shipments are not expected to exceed daily acceptance limits, where applicable. Careful coordination with some disposal facilities operators may be needed to avoid any logistical concerns regarding waste receipt scheduling. Nonetheless, any concerns regarding capacities or scheduling logistics at any single facility may be alleviated by measures such as use of multiple facilities (multiple facilities exist for all wastes evaluated in this EIS) or use of the truck/rail option for delivery of waste to rail-accessible facilities. Cultural resources. Archaeological and structural cultural resources. No combination of action alternatives would have an effect on architectural cultural resources because none has been identified as eligible for listing on the NRHP (i.e., no historic structures) and no impacts on this resource class have been determined under NEPA criteria. For archaeological resources, proposed exemptions to the 2010 AOC (DTSC 2010a) requirement to remediate chemical and radioactive contaminants to LUT values would allow DOE to avoid potential impacts on archeological sites that are listed or eligible for listing on the NRHP (i.e., historic properties) or otherwise significant under NEPA or CEQA eligibility criteria. For this reason, the potential adverse effects would be similar, but would vary somewhat among the alternatives. Under all alternatives, if an unanticipated archaeological resource is encountered, DOE would comply with applicable regulations and the Section 106 agreement document currently under development, which would include a provision for unanticipated archaeological finds. However, based on the intensive survey for archaeological sites, finding a previously unrecorded archeological resource is unlikely. S-81 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory The High Impact Combination would have the greatest potential to encounter unanticipated archaeological resources, primarily because this combination includes the Cleanup to AOC LUT Values Alternative which would cause the largest soil disturbance of any of the soil remediation action alternatives. The Building Removal Alternative would be unlikely to encounter unanticipated archaeological resources. Comparing the two groundwater remediation action alternatives, the Groundwater Treatment Alternative involves greater ground disturbance and construction and, thus, would have a greater potential to encounter unanticipated archaeological resources, were any to be present. If both groundwater remediation action alternatives were implemented, the potential for effects on unanticipated archaeological resources would be essentially the same as that from implementing the Groundwater Treatment Alternative alone. The Low Impact Combination would have the least potential to encounter unanticipated archaeological resources, primarily because this combination includes the Conservation of Natural Resources Alternative which would cause the least soil disturbance of any of the soil remediation action alternatives. As discussed above, the Building Removal Alternative would be unlikely to encounter unanticipated archaeological resources, and between the two groundwater remediation action alternatives, the Groundwater Monitored Natural Attenuation Alternative would have a lesser potential to encounter unanticipated archaeological resources. Traditional cultural resources. The 2010 AOC (DTSC 2010a) proposed an exemption from cleanup actions for “Native American artifacts that are formally recognized as Cultural Resources.” For example, the proposed exemption would apply to historic properties, such as those listed on, or eligible for listing on the NRHP. However, traditional cultural resources that include properties of traditional religious and cultural importance that do not meet the NRHP criteria could also be protected under the proposed exemption. The Santa Ynez Band of Chumash Indians has designated the entire SSFL, an area that includes all archaeological sites, regardless of NRHP eligibility, as well as all isolates and the landscape, as a Native American sacred site. They believe that the site is eligible for inclusion on the NRHP as a traditional cultural property. In 2014, they filed paperwork nominating the site to be included in the State of California Native American Heritage Commission Sacred Lands Inventory (NAHC 2014). DOE is consulting with SHPO, the Santa Ynez Band of Chumash Indians, and the SSFL Sacred Sites Council to develop an agreement intended to resolve adverse impacts through avoidance, minimization, or mitigation of impacts during and subsequent to cleanup activities. Under all action alternatives, there could be changes in setting as cleanup progresses in Area IV and the NBZ; after cleanup is complete, this impact would be removed, but the affected areas would have been re-contoured, which would change the setting of the traditional cultural resource. In addition, for traditional cultural resources, potential effects on archaeological sites are considered under all action alternative combinations because the Santa Susana Sacred Site includes all archaeological sites, regardless of NRHP eligibility, as well as all isolates and the landscape. The High Impact Combination would have the greatest potential to impact traditional cultural resources primarily because this combination would have the longest cleanup duration and the most landscape alteration. The Building Removal Alternative would be unlikely to encounter unanticipated archaeological resources and would remove structures that could be considered intrusive. Between the two groundwater remediation action alternatives, the Groundwater Treatment Alternative involves more ground disturbance and construction, and thus has more potential to encounter unanticipated archaeological resources or alter the landscape. The Groundwater Treatment Alternative would have a greater potential to affect the Santa Susana Sacred Site, and would involve more-extensive aboveground treatment facilities that could temporarily S-82 Summary affect its setting. This potential for impacts would be essentially the same if both groundwater remediation action alternatives were implemented. The Low Impact Combination would have the least potential to encounter unanticipated archaeological resources, primarily because this combination includes the Conservation of Natural Resources Alternative which would have shortest cleanup duration and least landscape alternation of any of the soil remediation action alternatives. As discussed above, the Building Removal Alternative would be unlikely to encounter unanticipated archaeological resources and would remove structures that could be considered intrusive. Between the two groundwater remediation action alternatives the Groundwater Monitored Natural Attenuation Alternative would involve less ground disturbance and construction, have less potential to affect the Santa Susana Sacred Site, and create less extensive structures (well heads) that could affect its setting. DOE is consulting with SHPO, the Santa Ynez Band of Chumash Indians, and the SSFL Sacred Sites Council to develop an agreement intended to resolve potential adverse impacts through avoidance, minimization, or mitigation of impacts during and subsequent to cleanup activities. Socioeconomics. The socioeconomics analysis addresses employment, potential economic impacts on businesses, infrastructure and municipal services in the SSFL ROI, as well as local government revenues, and potential economic impacts on businesses near the evaluated recycle and disposal facilities. Employment. For most years under the High Impact Combination, the number of onsite workers would range from 25 to 26 workers over 12 years of remediation. In addition, during the third year of the project, there would be a need for an additional five workers over about 6 working months to install groundwater treatment equipment and remove bedrock containing strontium-90. Under the Low Impact Combination, the number of onsite workers would be 25 to 26 for 4 years, plus 6 workers in a single year working an average of 5 days per well to install 5 groundwater monitoring wells. In addition, for all evaluated years, there would be 10 workers working an average of 1 month a year for environmental monitoring. Under any combination of action alternatives, site activities would have a minor beneficial impact on the economy in Los Angeles and Ventura Counties by providing employment and increasing sales for industries that provide equipment, supplies, and rentals. Because workers would likely originate from Los Angeles and Ventura Counties, new spending or economic activity in the region would be minimal. Truck traffic. The High Impact Combination would result in increased traffic in the SSFL vicinity over 12 years, with the most noticeable increase occurring on Woolsey Canyon Road. However, the additional vehicle traffic is not expected to result in socioeconomic impacts on businesses on this road, and traffic on other evaluated roads would increase by no more than 2.8 percent, assuming all traffic traversed each road, with minimal potential for socioeconomic impacts on businesses. The largest concentration of retail establishments, restaurants, and other businesses would occur on Topanga Canyon Road. The projected increase in average daily traffic (0.15 to 0.36 percent) is not expected to result in socioeconomic impacts on businesses along this road. Traffic under the Low Impact Combination would increase in the SSFL vicinity, primarily over the first 4 years, with much smaller increases thereafter. Again, the additional vehicle traffic is not expected to result in socioeconomic impacts on businesses on Woolsey Canyon Road, and average daily traffic on other evaluated roads would increase by no more than 2.7 percent, assuming all traffic traversed each road, with minimal potential for socioeconomic impacts on businesses. The average daily traffic on Topanga Canyon Boulevard under the Low Impact Combination would increase by 0.15 to 0.35 percent during the first 4 years of site remediation, and by less than S-83 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory 0.01 percent thereafter, which is not expected to result in socioeconomic impacts on businesses along this road. Under any combination of action alternatives, the increased amount of truck traffic would be insufficient to result in socioeconomic impacts in the SSFL ROI. Infrastructure and municipal services. Under any combination of action alternatives, there could be damage to local roads from the potentially large number of trucks required for remediation of Area IV and the NBZ. Recognizing this, DOE may need to negotiate with local governments to contribute its portion of the cost for maintenance and repair of affected roads. No impacts on other municipal services are expected. Housing. For any combination of action alternative, workers would be primarily employed from Los Angeles and Ventura Counties, with no impacts on housing availability. Local government revenue. The High Impact Combination would have the largest potential beneficial and adverse impacts on local government revenue because increased activities, including truck traffic, would occur for 12 years. The Low Impact Combination would have the potential smallest beneficial and adverse impacts on local government revenue because increased activities, including truck traffic would primarily occur for 4 years. Beneficial impacts could result from increased revenues from fuel taxes, fees, or other project expenses, while adverse impacts could result from increased expenses for pavement repair. Disposal facilities. Disposal facility impacts depend on the quantities of radioactive, hazardous, and nonhazardous wastes to be delivered. There is a significant difference among the combinations of action alternatives for shipment of LLW and MLLW. LLW and MLLW would be delivered to an assumed single disposal facility at average daily rates ranging from 2 to 5 deliveries for either combination of action alternatives that includes the Cleanup to AOC LUT Values Alternative, with deliveries occurring over 12 years. For combinations of action alternatives that include the Cleanup to Revised LUT or Conservation of Natural Resources Alternative, deliveries would range up to 14 per day, with deliveries occurring over slightly over 3 years to 4 years. Peak deliveries (14 per day) under these action alternative combinations would last for only 1 to 2 years. This truck traffic is not expected to cause socioeconomic impacts on businesses in the vicinities of the evaluated disposal facilities. There is almost no difference among the combinations of action alternatives for shipment of hazardous waste. Hazardous waste would be shipped under the Building Removal Alternative and in equal quantities under all soil remediation action alternatives. The only difference among all action alternatives is that very small quantities of hazardous waste (about 26 cubic yards) might be generated under the Groundwater Treatment Alternative. The largest average daily truck delivery to a single assumed hazardous waste facility would be 8 deliveries. This frequency of truck traffic is not expected to have socioeconomic impacts on businesses in the vicinities of the evaluated disposal facilities. The differences among the combinations of action alternatives for shipment of nonhazardous waste are primarily due to differences in soil volumes removed under the soil remediation action alternatives. Under the combination of the Cleanup to AOC LUT Values, Building Removal, and Groundwater Treatment Alternatives, waste would be shipped to disposal facilities over 12 years, and the average number of heavy-duty trucks received at a single assumed disposal facility could range up to 25 per day. Under the combination of the Cleanup to Revised LUT Values, Building Removal, and Groundwater Treatment Alternatives, waste would be shipped to disposal facilities over slightly over 4 years, and the average number of heavy-duty trucks received at a single assumed disposal facility could range up to about 8 per day. Under the combination of the Conservation of S-84 Summary Natural Resources, Building Removal, and Groundwater Treatment Alternatives, waste would be shipped to disposal facilities over 4 years, and the average number of heavy-duty trucks received at a single assumed disposal facility could range up to about 8 per day. Assuming all nonhazardous waste was shipped to a single nonhazardous waste facility, no or only minimal socioeconomic impacts are expected because of the locations of the facilities and/or the ease of access from major highways. Deliveries to an assumed single recycle facility would average up to two trucks per day, assuming all deliveries were made during 2 to 5 months in each of 2 years. The daily number of delivery trucks would be reduced if waste was shipped throughout each working year. The minimal increased daily deliveries would have no impacts on traffic volumes in the vicinities of any of these recycle facilities, and, thus, no socioeconomic impacts are expected in the vicinities of any of the evaluated facilities. Although potential socioeconomics impacts on businesses in the vicinity of any single facility accepting recyclable material or radioactive, hazardous, or nonhazardous waste for disposal are minimal (at worst), these potential impacts could be further reduced by shipping waste to multiple authorized facilities; by using multiple routes (as available) for delivery to individual facilities; or by shipping waste by rail to rail-accessible disposal facilities. Environmental justice. SSFL ROI. Under any combination of action alternatives, the risks to a member of the public of both the incidence of cancer and a cancer fatality would be dominated by potential impacts from background concentrations of chemical and radioactive constituents. Therefore, there would be no disproportionately high and adverse impacts on Native American tribes and minority and lowincome populations. Under the High Impact Combination, the largest increase in daily traffic would occur on Woolsey Canyon Road, where over 12 years, the average daily traffic would increase by 3.4 to 7.6 percent. If both groundwater remediation action alternatives were implemented, there would be essentially the same increase in average daily traffic as that presented above. Under the Low Impact Combination, the largest increase in daily traffic volume would occur on Woolsey Canyon Road, where the average daily traffic would increase by 3.5 to 7.4 percent over 4 years, with minor traffic increases thereafter. Under both combinations of action alternatives, there would be considerably smaller increases in traffic on the other evaluated roads between SSFL and major highways. Although there would be increases in the traffic on the evaluated routes between SSFL and major highways, the routes would traverse minority and non-minority communities, as well as low-income and non-low-income communities, and would not pass through Native American lands. This indicates that potential impacts on Native American tribes and minority or low-income populations would be the same as those experienced by the general population. Other than Woolsey Canyon Road, traffic volumes on the evaluated roads could be reduced by using multiple routes to major highway systems. No disproportionately high and adverse impacts are expected on Native American tribes and minority and low-income populations in the SSFL ROI. Regional ROIs. Regional environmental justice impacts depend on the quantities of radioactive, hazardous, and nonhazardous wastes that would be delivered to the disposal facilities and the schedules for these deliveries. There is a significant difference among combinations of action alternatives regarding the shipped quantities of radioactive waste, primarily resulting from differences in soil removals under the soil remediation action alternatives. Total volumes could range from 57,600 cubic yards to 103,000 cubic yards, and the average daily deliveries to a single assumed LLW/MLLW facility could range from less than 1 to about 14. Even if all waste deliveries were made to a single LLW/MLLW S-85 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory disposal facility, the projected frequency of truck traffic would not result in noticeable traffic-related impacts in the ROI for that facility. There is almost no difference among the combinations of action alternatives regarding the total quantity of hazardous waste (about 26 cubic yards), although daily deliveries to the evaluated disposal facilities would differ as would the duration of the deliveries. Even if all waste deliveries were made to a single hazardous waste disposal facility, the projected frequency of truck traffic (up to 8 truck deliveries per day) would not result in noticeable traffic-related impacts in the ROI for that facility. There are significant differences among the combinations of action alternatives for shipped quantities of nonhazardous waste; these differences primarily result from differences in the soil volumes removed under the soil remediation action alternatives. Under the combination of the Cleanup to AOC LUT Values Alternative, Building Removal Alternative, and either groundwater remediation action alternative, about 794,000 cubic yards of nonhazardous waste (soil, debris, etc.) would be shipped to disposal facilities over 12 years. The average number of heavy-duty trucks received at nonhazardous sites could range up to 25 trucks per day. There would be no or minimal impacts from increased traffic in the vicinities of the evaluated facilities. Under the combination of either the Cleanup to Revised LUT Values or Conservation of Natural Resources Alternative, the Building Removal Alternative, and either groundwater remediation action alternative, however, about 53,200 cubic yards of nonhazardous waste would be generated. This waste would be shipped to disposal facilities over approximately 4 years. The average number of heavy-duty trucks delivered to a single assumed nonhazardous waste facility could be up to 8 per day during 2 years; daily deliveries during other years would be smaller. This frequency of truck traffic is not expected to result in traffic-related impacts in the ROI for that facility. Under any combination of action alternatives, about 3,540 cubic yards of recyclable material would be shipped to recycle facilities during 2 years of building demolition. As addressed in the socioeconomics section, the minimal increased daily deliveries would have no impacts on traffic volumes in the vicinities of any of these recycle facilities. The number of truck deliveries to any single facility could be reduced if multiple disposal facilities were used, if multiple routes (as available) were used in the vicinities of individual facilities, or if waste were shipped to one or more rail-accessible facilities. Considering this and the above analysis, no combination of action alternatives would have disproportionately high and adverse impacts on Native American tribes and minority and low-income populations in the regional ROIs for the evaluated recycle and disposal facilities. Sensitive-aged populations. SSFL ROI. Under both the High and Low Impact Combinations, average daily traffic would increase on Woolsey Canyon Road, as discussed in the environmental justice section. There would be no noticeable additional increases if both groundwater remediation action alternatives were implemented. Under both combinations of action alternatives, but for a longer duration under the High Impact Combination than under the Low Impact Combination, this increased traffic could result in greater risks to pedestrians along or crossing Woolsey Canyon Road, although these risks would be experienced by persons of all ages. Traffic volumes on other evaluated roads are not expected to be noticeably larger than those under baseline conditions. In addition, traffic on all evaluated roads, other than Woolsey Canyon Road, that pass by or are in the vicinity of schools or recreation areas could be reduced by distributing traffic among the evaluated traffic routes. Under any combination of action alternatives, therefore, no disparate impacts (markedly distinct impacts S-86 Summary relative to those on the general population) are expected on sensitive-aged populations in the SSFL ROI. Regional ROIs. As discussed in the environmental justice section, even if all radioactive waste deliveries were made to a single facility and all hazardous waste deliveries were made to a single facility, the projected truck traffic would not result in noticeable traffic-related impacts. Furthermore, no schools or recreation areas have been identified in the ROIs of the evaluated radioactive and hazardous waste facilities. Therefore, no disparate impacts are expected on sensitive-aged populations in these ROIs. The combination of the Cleanup to AOC LUT Values Alternative, the Building Removal Alternative, and either groundwater remediation action alternative would generate the most nonhazardous waste to be shipped to offsite facilities. Assuming all nonhazardous waste was shipped to a single assumed facility, traffic-related impacts are expected to be minimal at the two evaluated facilities with a school or recreation area in their vicinities (Antelope Valley Landfill and McKittrick Waste Treatment Site, both in California). The combination of either the Cleanup to Revised LUT or Conservation of Natural Resources Alternative, the Building Removal Alternative, and either groundwater action alternative combination would generate the least amount of nonhazardous waste. The average number of heavy-duty trucks delivered to a single assumed nonhazardous waste facility could be up to 8 per day during 2 years; daily deliveries during other years would be smaller. The potential impacts of this increased traffic at any single assumed facility would be minimal. Furthermore, for any combination of action alternatives, the number of truck deliveries to any single facility could be reduced if multiple disposal facilities were used or if waste were shipped to one or more rail-accessible facilities. Therefore, no disparate impacts on sensitiveaged populations are expected in the regional ROIs for the evaluated nonhazardous waste facilities under any combination of action alternatives. S.11.3 Summary of Potential Cumulative Impacts “Council on Environmental Quality Regulations for Implementing the Procedural Provisions of the National Environmental Policy Act” (40 CFR Parts 1500-1508) define cumulative effects as impacts on the environment that result from the incremental impacts of the proposed action when added to the incremental impacts of other past, present, and reasonably foreseeable future actions, regardless of which agency or person undertakes such other actions (40 CFR 1508.7). Reasonably foreseeable onsite actions at SSFL included in the cumulative impact analysis of this EIS are ongoing and planned demolition, remediation, and waste transportation activities conducted by DOE, NASA, and Boeing. Activities in the SSFL ROI that could contribute to cumulative impacts could include new residential development, new industrial and commercial ventures, resource investigation and development, new utility and infrastructure development, new waste treatment and disposal facilities, and contaminated site remediation. Future actions that are speculative or are not well defined were not analyzed, including the future use of SSFL. Potential cumulative impacts are summarized in Table S–10 for each resource area. Chapter 5 presents the detailed cumulative impacts analysis which includes a more detailed discussion of the onsite and offsite activities considered in this cumulative impacts assessment. S-87 S-88 Table S-10 Summary of Potential Cumulative Impacts Land resources Geology and soils Land use: 40 to 138 acres disturbed; no zoning or land use conflicts. Recreation: Increased traffic could discourage weekday use of Sage Ranch Park; no impacts on other recreation areas in the SSFL vicinity are expected. Infrastructure: 3,000 to 16,000 gallons per day water consumption for dust suppression. Aesthetics and visual quality: Removal of buildings and revegetation would result in beneficial long-term effects on aesthetics and visual quality. NASA and Boeing Contribution to Cumulative Impacts Land use: 194 to 275 acres disturbed; no zoning or land use conflicts. Approximately 20 acres of additional undeveloped land in the Southern Buffer Zone could be disturbed if Boeing uses these areas as sources of clean backfill. Recreation: Increased traffic could discourage weekday use of Sage Ranch Park; no impacts on other recreation areas in the SSFL vicinity are expected. Infrastructure: 210,000 to 214,000 gallons per day water consumption for dust suppression. Aesthetics and visual quality: Removal of buildings and revegetation would result in beneficial long-term effects on aesthetics and visual quality. There would be 40 to 138 acres of There would be 194 to 275 acres of soil disturbance and loss of soil with soil disturbance and loss of soil with mineralogical and biological mineralogical and biological composition capable of supporting composition capable of supporting unique vegetation in Area IV and unique vegetation at SSFL. the NBZ. 315,000 to 403,000 cubic yards of 125,000 to 715,000 cubic yards of backfill would be needed. It is unlikely backfill would be needed. It is that an offsite source of backfill unlikely that a source of backfill meeting the NASA AOC LUT values meeting the DOE AOC LUT values would have the same physical and would have the same physical and chemical properties as existing SSFL chemical properties as existing SSFL soils. soils. Boeing has identified potential borrow areas for backfill in the Southern Buffer Zone. If soil is taken from these borrow areas, up to an additional 20 acres could be disturbed. Other Contributions to Cumulative Impacts Cumulative Impacts Land use: acreage disturbed not available. Recreation: No impacts identified. Infrastructure: Annual water use for CMWD averages 177,644 acre feet (or approximately 159 million gallons per day). Aesthetics and visual quality: No impacts identified. Land use: 235 to 414 acres disturbed; no zoning or land use conflicts Recreation: Increased traffic could discourage weekday use of Sage Ranch Park; no impacts on other recreation areas in the SSFL vicinity are expected. Infrastructure: SSFL water use would be approximately 0.1 percent of CMWD’s combined water supply, but because of severe drought California is attempting to reduce potable water consumption state-wide by 25 percent. Therefore, cumulative SSFL water use, although small, may be controversial. Aesthetics and visual quality: Removal of buildings and revegetation would result in beneficial long-term effects on aesthetics and visual quality. Other construction activities in the region could disturb soils. Although stormwater pollution prevention plan requirements and BMPs would limit soil erosion, some soil erosion is likely. If the soils are similar to those present at SSFL, cumulative impacts to these soil types could result. Other construction activities in the region could require soils for backfill, but are just as likely to result in excess soil from foundation excavation and slope cutting. Therefore, these activities are not likely to consume a large quantity of soil and contribute to a soil shortage. There would be 235 to 414 acres of soil disturbance and loss of soil with mineralogical and biological composition capable of supporting unique vegetation at SSFL. 440,000 to 1,120,000 cubic yards of backfill would be needed. It is unlikely that a source of backfill meeting DOE and NASA AOC LUT values would have the same physical and chemical properties as existing SSFL soils. Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Resource Area DOE Contribution to Cumulative Impacts Resource Area Surface water resources Groundwater resources DOE Contribution to Cumulative Impacts NASA and Boeing Contribution to Cumulative Impacts Other Contributions to Cumulative Impacts With implementation of control and mitigation measures, DOE’s actions would generate no impacts on surface water quality or on local and regional stormwater control capacity, and would not contribute to cumulative impacts. Cleanup would result in a long-term reduction of potential sources of surface water contamination. Impacts on the quantity of site groundwater are expected to be minimal because groundwater would not be withdrawn during soil excavation. If required, removal of 200,000 gallons of groundwater during demolition of one of the DOE buildings would have a shortterm, localized impact on water levels. Because of the relatively small size of SSFL compared to the adjacent groundwater basins and the relatively small quantity of groundwater that would be withdrawn, none of the proposed groundwater remediation technologies are expected to have an appreciable impact on the quantity of groundwater available for use by populations in adjacent groundwater basins. DOE groundwater cleanup activities at SSFL would have a long-term beneficial impact on groundwater quality. With implementation of control and mitigation measures, NASA’s and Boeing’s actions would generate no impacts on surface water quality or on local and regional stormwater control capacity and would not contribute to cumulative impacts. Cleanup would result in long-term reduction of potential sources of surface water contamination. Impacts on the quantity of site groundwater are expected to be minimal because groundwater is deeper beneath the NASA- and Boeing-administered areas and is not expected to be withdrawn during soil excavation. Because of the relatively deep groundwater and because the buildings and other structures have shallow foundations, demolition of buildings is not expected to require dewatering. Because of the relative size of SSFL compared to the adjacent groundwater basins and the relatively small quantities of groundwater that are expected to be withdrawn, none of the proposed groundwater remediation technologies is expected to have an appreciable impact on the quantity of groundwater available for use by populations in adjacent groundwater basins. NASA and Boeing groundwater cleanup activities at SSFL would have a long-term beneficial impact on groundwater quality. Offsite developments would be subject to compliance with stormwater pollution prevention plans and BMPs that would limit the potential for increased soil erosion and sediment loading in runoff during construction and operation. Cumulative Impacts With implementation of control and mitigation measures, DOE, NASA, and Boeing actions at SSFL would generate no impacts on surface water quality or local and regional stormwater control capacity and would not be expected to contribute to cumulative impacts. Cleanup would result in long-term reduction of potential sources of surface water contamination. No other contributions to cumulative Because of the relatively small size of SSFL impacts in the ROI were identified. compared to the adjacent groundwater basins, the depth to the aquifer, and the relatively small quantities of groundwater that would be withdrawn, none of the proposed remediation technologies are expected to have an appreciable impact on the quantity of groundwater available for use by populations in adjacent groundwater basins. Groundwater cleanup activities at SSFL would have a long-term beneficial impact on groundwater quality. Summary S-89 S-90 Resource Area DOE Contribution to Cumulative Impacts 40 to 138 acres disturbed, including about 13 to 51 acres of relatively undisturbed native habitat. Removal of existing vegetation and topsoil would increase the difficulty of re-establishing native plant species and would reduce or eliminate the value of re-established habitat for most wildlife species. Remediation would require prolonged efforts to restore native vegetation and wildlife habitat. If backfill is substantially different than that originally present, it may not support native vegetation. Air quality and climate Onsite activities would not contribute to exceedance of an ambient air quality standard at an offsite location. There would be 32 to 48 daily heavy-duty truck round trips (the maximum from SSFL between DOE, NASA, and Boeing would be 96, per the Transportation Agreement [Boeing 2015a]). These trips would extend across hundreds of miles of roadways, depending on the route taken to a disposal facility. As a result, emissions would be dispersed in the atmosphere to the point that they would produce minimal impacts in a localized area. Implementation of a green cleanup truck fleet proposed by DOE would minimize project air quality impacts. The total carbon dioxide emissions generated by the high DOE combination of alternatives would be 89,000 metric tons. 194 to 275 acres disturbed. Similar impacts as described for DOE. Approximately 20 acres of additional undeveloped land in the Southern Buffer Zone could be disturbed if Boeing uses these areas as sources of clean backfill. Other Contributions to Cumulative Impacts Projects outside SSFL are generally sufficiently distant to minimize the potential for cumulative effects with the remediation projects on SSFL. However, certain proposed projects (such as Sterling Properties in Dayton Canyon) developed on land that supports threatened, endangered, or rare species or relatively undisturbed native habitat of the same type that would be affected by SSFL remediation activities (e.g., oak woodlands and habitat for Braunton’s milk-vetch and Santa Susana tarplant) could have cumulative adverse impacts. Onsite activities would not contribute Numerous cumulative projects, such to exceedance of an ambient air quality as those listed in Appendix D, standard at an offsite location. There Table D-7, would cause additional would be 48 to 64 daily heavy-duty emissions impacts within the South truck round trips. As a result, Coast Air Basin. emissions would be dispersed in the atmosphere to the point that they would produce minimal impacts in a localized area. NASA and Boeing cleanup actions would emit about 139,000 and 30,000 metric tons of carbon dioxide, respectively. Cumulative Impacts 235 to 414 acres disturbed at SSFL. The combined soil excavation and building removal activities of DOE, NASA, and Boeing would cause profound disturbance (removal of vegetation and soils). The effects of vegetation and soil removal could result in long-term impacts due to the intense effort needed to restore the habitat. Simultaneous implementation of remediation activities by DOE, NASA, and Boeing would create cumulative disturbance of habitat and could interfere with regional movement of wildlife species such as mountain lion, bobcat, and ringtail. Onsite activities would not contribute to exceedance of an ambient air quality standard at an offsite location, except possibly for occasional exceedances of particulate matter standards. For the South Coast Air Basin region, an area already in extreme nonattainment for the ambient ozone standards, emissions of ozone precursors from DOE activities, in combination with ozone precursor emissions from cumulative projects, would have the potential to contribute to exceedance of an ozone standard. Emissions generated from proposed DOE activities outside of Ventura County and the South Coast Air Basin would be diluted in the atmosphere and would produce minimal impacts in a localized area. Emissions from DOE trucks traveling within the San Joaquin Valley Air Basin (which has extreme nonattainment for ambient ozone standards), combined with cumulative emissions from other traffic has the potential to contribute to an exceedance of an ambient ozone standard within this region. Implementation of a green cleanup truck fleet proposed by DOE would minimize project air quality impacts. The total cumulative carbon dioxide emissions generated by SSFL cleanup activities would be 258,000 metric tons, a negligible contribution to future climate change. Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Biological resources NASA and Boeing Contribution to Cumulative Impacts Resource Area Noise DOE Contribution to Cumulative Impacts Remediation activities conducted by NASA and Boeing are expected to generate noise levels similar to those generated by DOE remediation activities. Other Contributions to Cumulative Impacts Offsite residential, commercial, and industrial development projects typically generate temporary localized elevated noise levels at the construction site, temporary increases in construction truck traffic noise along nearby roads, and localized increases in noise levels during project operation. Construction and operations noise would be localized near the individual project sites following a similar pattern to noise levels described for construction activities on SSFL. Therefore, noise from offsite development projects would generally not be cumulative with activities on SSFL. Cumulative Impacts Projected noise levels at the closest residence to onsite remediation activities would be well below 65 dBA CNEL. Assuming 96 daily truck round trips, time-averaged noise levels in residential and recreation areas along potential haul routes are expected either to increase by no more than 5 dBA CNEL (the threshold for an adverse impact where the final noise level would be below 65 dBA CNEL) or by no more than 3 dBA CNEL (the threshold for an adverse impact where the final noise level would be above 65 dBA CNEL). Noise levels for truck transportation would not increase over levels described for DOE activities alone because the total number of DOE, NASA, and Boeing daily truck round trips would not exceed 96, in accordance with the Transportation Agreement (Boeing 2015a). Although cumulative noise levels would not be greater than the levels for DOE activities alone, these higher levels would occur for a longer period of time. In a hypothetical scenario where a development project was undertaken adjacent to existing residences, the noise of the development project would be dominant, and distant noise generated at SSFL, which is more than 5,000 feet from the closest residence, would not contribute appreciably to overall noise levels. Truck trips conducted in support of other projects in the ROI could potentially follow portions of the same routes used by SSFL trucks. Any cumulative increase in truck traffic noise would be temporary. Therefore, only minor cumulative noise impacts are expected. Summary The nearest potential residence is located approximately 5,000 feet from the Area IV boundary and would experience an approximate 50 dBA equivalent sound level during workday hours. Assuming the maximum authorized number of daily round trips from Area IV (96 total round trips by DOE, NASA, and Boeing), time-averaged noise levels in residential and recreation areas along potential haul routes are expected to increase by up to 3.5 dBA CNEL, where the final noise level would be below 65 dBA CNEL (the threshold for an adverse impact is an increase of 5 dBA CNEL) or, along one section of Valley Circle Boulevard where the noise level already exceeds 65 dBA CNEL, the noise level would increase by no more than 0.6 dBA CNEL (the threshold for an adverse impact when the final noise level exceeds 65 dBA CNEL is an increase of 3 dBA CNEL). NASA and Boeing Contribution to Cumulative Impacts S-91 S-92 Resource Area Traffic NASA and Boeing Contribution to Cumulative Impacts Radiological impacts: Collective transportation worker dose of 0.14 to 1.5 person-rem and collective general population dose of 0.092 to 0.39 person-rem. No LCFs would be anticipated. Nonradiological impacts: 0.28 to 2.9 potential accident fatalities could result from DOE transportation activities. Radiological impacts: NASA remediation activities are expected to generate a collective worker dose 0.50 person-rem and a collective general population dose of 0.19 person-rem. No LCFs would be anticipated.a Boeing remediation activities are not expected to generate any radioactive waste. Nonradiological impacts: 1 (0.50 to 0.58) potential accident fatality could result from NASA and Boeing transportation activities. Other Contributions to Cumulative Impacts Radiological impacts: The total number of potential LCFs (among the workers and general population) estimated to result from nationwide radioactive material transportation over the period between 1943 and 2073 is 514, or an average of 4 LCFs per year. The transportation-related LCFs represent about 0.0007 percent of the total number of cancer deaths expected over the same time period; therefore, this rate is indistinguishable from the natural fluctuation in the annual death rate from cancer. Nonradiological impacts: 43,000 estimated traffic fatalities in California from 2017 through 2028. 11,400 estimated traffic fatalities in the four neighboring counties (2017 through 2028). Level of service: The largest Level of service: The largest Level of service: Current LOS weekday, average daily traffic percentage traffic increase would be on ratings on routes from SSFL range increase would be on Woolsey Woolsey Canyon Road (22.4 to from B (stable traffic flow with no Canyon Road (3.4 to 7.6 percent). 26.5 percent). The LOS rating on delay) to F (forced traffic flow with The LOS rating on Woolsey Canyon Woolsey Canyon Road could degrade considerable delay). Road could degrade from LOS B to from LOS B to C. Pavement deterioration: C for approximately 4 to 12 years. Pavement deterioration: 86,400 to Estimated baseline ESALs range Pavement deterioration: 20,800 109,000 additional truck trips, from 38,000 to 74,000, depending on to 119,000 additional truck trips, depending on the remediation option; the route. depending on the alternative; ESALs would increase by 220,000 to ESALs would increase by 45,000 330,000 from NASA and Boeing truck (Low Impact Combination) to trips. 210,000 (High Impact Combination) from DOE truck trips. Cumulative Impacts Radiological impacts: Collective worker dose of 0.64 to 2 person-rem and collective general population dose of 0.28 to 0.58 person-rem. No LCFs would be anticipated. The potential doses from transport of radioactive materials associated with remediation activities at SSFL are insignificant compared to the doses from other nuclear material shipments. The majority of the cumulative risk to workers and the general population would be due to general transportation of radioactive material unrelated to remediation activities at SSFL. Nonradiological impacts: 1 (0.79) to 4 (3.5) potential accident fatalities could result from SSFL (DOE, NASA, and Boeing) transportation activities; representing about 0.008 percent of the total number of traffic fatalities expected in California and 0.03 percent of the total number of traffic fatalities expected in the four surrounding counties. The potential traffic fatalities from operations at SSFL are indistinguishable from the natural fluctuation in the total annual death rate from traffic fatalities. Level of service: Largest percentage traffic increase would be on Woolsey Canyon Road (30 percent). The LOS on Woolsey Canyon Road could degrade from LOS B to C. Pavement deterioration: Estimated single axle loads associated with DOE, NASA, and Boeing remediation activities at SSFL would increase from a baseline of 38,000 to 74,000, to 260,000 to 540,000, depending on the alternative. Between 17 and 39 percent of the increase would be attributable to DOE activities. Increased truck traffic could further damage the surrounding roads, causing them to need repair sooner than currently anticipated. Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Transportation DOE Contribution to Cumulative Impacts Resource Area Human health DOE Contribution to Cumulative Impacts NASA and Boeing Contribution to Cumulative Impacts Other Contributions to Cumulative Impacts Because the DOE onsite suburban None identified. resident scenario already includes exposure for 24 hours a day, 350 days per year for 30 years, consistent with the SRAM, no additional time could be spent on NASA or Boeing areas of SSFL. The total exposure time for a hypothetical recreational user would not increase, regardless of which area of SSFL is being traversed. Worker exposure to chemical and radioactive constituents could occur during soil remediation, building demolition, and groundwater remediation. Physical and administrative controls would be employed to ensure that workers would be protected in compliance with DOE requirements for worker safety and radiation protection. Radiation protection practices would be employed so that radiation doses are ALARA. Worker exposure to chemical and radioactive constituents could occur during soil remediation, building demolition, and groundwater remediation. Physical and administrative controls would be employed to ensure that workers would be protected in compliance with regulatory requirements for worker safety and radiation protection Cumulative Impacts Because the onsite resident scenario conservatively includes exposure for 24 hours a day, 350 days per year for 30 years, consistent with the SRAM, no additional time could be spent on NASA or Boeing areas of SSFL. A resident can only be in one area at a time and cannot be in both areas simultaneously. Therefore, the effects are not additive, and the cumulative effect cannot be greater than the greater of the individual area efforts. The impacts from adjacent areas under control of NASA or Boeing to a resident in Area IV would result in a minimal addition to cumulative impacts because these areas are separated by significant distances relative to a residential exposure scenario. Likewise, the contributions from Area IV to hypothetical onsite suburban residents in NASA or Boeing remediation areas also would be small and would make a minimal addition to cumulative impacts. It is unlikely that the same workers would perform remediation work for DOE, NASA, and/or Boeing because remediation activities are planned to occur in overlapping years. If workers do perform remediation work in more than one area, they can only be in one area at a time and would not be exposed to both simultaneously. Whatever time they spend in one area takes away from the time they could spend in another area and would be limited to applicable regulatory standards and guidelines. Because work practices during excavation or demolition would control dust, impacts would be localized to the work area. Therefore, contributions from remediation activities in one area of SSFL on remediation workers in an adjacent area would only minimally add to cumulative impacts on worker health. Summary A hypothetical onsite suburban resident or recreational user is assumed to be exposed to contaminated soil in Area IV for 24 hours a day, 350 days per year for 30 years, consistent with the SRAM. A hypothetical recreational user is assumed to be exposed 8 hours per day for 75 days per year for 30 years. S-93 S-94 Resource Area Cultural resources NASA and Boeing Contribution to Cumulative Impacts Considering all DOE soil remediation, building demolition, and groundwater remediation activities, DOE would generate 57,600 to 103,300 cubic yards of LLW/MLLW, about 49,100 cubic yards of hazardous waste, 53,200 to 794,000 cubic yards of nonhazardous waste, and 3,540 cubic yards of recyclable material. Archaeological resources: NRHP-eligible sites would be protected from impacts (i.e., adverse effects) through implementation of a Programmatic Agreement under Section 106 of the NHPA. Sites that are not individually eligible, but are contributing elements of the Santa Susana Sacred Site, could be adversely impacted. However, cultural resources that do not meet the NRHP criteria could be protected under the 2010 AOC exemption process. Architectural resources: No structures located in DOEadministered areas are NRHPeligible. Traditional cultural resources: The character-defining traits of the Chumash-designated Santa Susana Sacred Site include all archaeological and natural resources, settings, and viewsheds. Cleanup activities would affect some archaeological resources. Plants and animals may be disturbed, dislocated, or destroyed. Beneficial impacts would be achieved through restoration of viewsheds by removal of structures. Removal of contamination would also be beneficial. Considering all soil remediation and building removal activities, NASA could generate 87,000 cubic yards of LLW/MLLW (no LLW/MLLW would be generated by Boeing). NASA and Boeing combined would generate 489,700 to 752,700 cubic yards of hazardous waste, 398,000 cubic yards of nonhazardous waste, and 37,700 cubic yards of recyclable material. Archaeological resources: NRHPeligible areas on NASA-administered lands would be protected from impacts (i.e., adverse effects) from implementation of its Programmatic Agreement under Section 106 of the NHPA. Architectural resources: NASA proposes to preserve one or more NRHP-eligible structures, but demolition of other structures would contribute to cumulative effects. Traditional cultural resources: Impacts from NASA and Boeing activities on the Chumash-designated Santa Susana Sacred Site would have similar impacts on those described for DOE. Beneficial impacts would be achieved through restoration of viewsheds by removal of structures. Removal of contamination would also be beneficial. Other Contributions to Cumulative Impacts None identified. Cumulative Impacts DOE is projected to generate and ship off site about 40 to 54 percent of the SSFL cumulative volume of LLW and MLLW, 6 to 9 percent of the cumulative volume of hazardous waste, 12 to 67 percent of the cumulative volume of nonhazardous waste (primarily soil), and about 9 percent of the cumulative volume of recyclable material. Sufficient capacity exists for all types of waste generated by DOE, NASA, and Boeing, and the impact on any single facility’s capacity can be reduced by sending waste to multiple disposal facilities. Of the 129 actions identified within Archaeological resources: The overall trend in the 10 miles of SSFL, as many as 21 have region is toward a reduction in NRHP-eligible the potential to contribute to archaeological sites, both pre-contact Native cumulative impacts. American and post-contact, as these impacts accumulate. Where NHPA is applicable, adverse Archaeological resources: Largeeffects to NRHP-eligible sites would be mitigated, scale developments outside SSFL but mitigation could include removal of the site. would contribute to cumulative Where NHPA is not applicable or where sites are not adverse impacts if archaeological eligible, sites may be removed from the overall sites are disturbed during project inventory of archaeological resources. The construction, paved over, or protection of NRHP-eligible sites at SSFL would not disturbed at a later date due to add to cumulative regional impacts. However, the human activity. overall complement of archaeological sites, Architectural resources: None particularly those that are not eligible for the NRHP, specifically identified. could continue to be reduced. Traditional cultural resources: Architectural resources: Because there are no Loss of defining characteristics of NRHP-eligible structures within the DOE area of traditional cultural values at other potential effects, DOE cleanup activities would have locations within the ROI could add no cumulative effect on architectural resources. to cumulative impact on the Traditional cultural resources: Cumulative viewsheds. adverse effects on traditional cultural resources are likely as cleanup occurs on the entire SSFL and as development occurs in previously undeveloped land in the ROI, including in areas with intact landscapes or remote locations where traditional resources may still retain integrity. Beneficial impacts would be achieved through restoration of viewsheds by removal of structures at SSFL. Removal of contamination at SSFL would also be beneficial. Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Waste management DOE Contribution to Cumulative Impacts Resource Area Socioeconomics NASA and Boeing Contribution to Cumulative Impacts Other Contributions to Cumulative Impacts Employment: DOE onsite activities would require 25 to 26 workers. Workers would likely originate primarily from Ventura and Los Angeles Counties. Truck drivers and traffic: DOE would require from 32 to 48 truck drivers. A maximum of 95 truck drivers could be required for 2-day truck trips to distant facilities. Traffic conditions near businesses would not change substantially. Infrastructure and municipal Services: Impacts on roads would result in impacts on local government funding and expenses. DOE may need to negotiate with local governments to contribute its portion of the cost for maintenance and repair of affected roads. Housing availability: Because workers would likely originate from the region, changes to housing availability are not expected. Disposal facility impacts: Increases in truck traffic are not expected to have a cumulative adverse economic impact on local businesses near disposal facilities because the maximum number of daily truck trips would be relatively small. The largest number of daily shipments would be to a nonhazardous waste facility (25 shipments).b Employment: NASA and Boeing onsite activities would require 150 to 175 workers. Workers would likely originate primarily from Ventura and Los Angeles Counties. Truck drivers and traffic: NASA and Boeing would require an estimated 9 to 42 truck drivers. A maximum of 202 truck drivers could be required for 2-day truck trips to distant facilities. Traffic conditions near businesses would not change substantially. Infrastructure and municipal Services: Impacts on roads would result in impacts on local government funding and expenses. Housing availability: Because NASA and Boeing workers would likely originate from the region, changes to housing availability are not expected. Disposal facility impacts: Increases in truck traffic are not expected to have a cumulative adverse economic impact on local businesses near disposal facilities because the maximum number of daily truck trips would be relatively small. The largest number of daily shipments would be to a nonhazardous waste facility (42 shipments).b The populations in Los Angeles and Ventura Counties are projected to increase by 9 percent from 2013 through 2030. Employment: More than 117,000 construction workers are in the region. Truck drivers and traffic: Approximately 7,200 workers are employed in specialized freight trucking in the region, plus approximately 26,600 employees in general truck transportation. Infrastructure and municipal services: Population growth could increase traffic levels, but also could increase spending by local and state government agencies on roadways and mass transit projects. Housing availability: Projected population growth in the ROI would increase the demand for housing. Future housing development is expected to meet the demands of population growth. Disposal facility impacts: None identified. Cumulative Impacts Employment: SSFL remediation activities would require 175 to 201 workers. SSFL site activities would have a minor beneficial impact on the economy in Los Angeles and Ventura Counties by providing employment and increasing sales for industries that provide equipment, supplies, and rentals. Because workers would likely originate from the region, new spending in the region would be minimal. Truck drivers and traffic: Employment of 73 to 297 SSFL truck drivers would represent 1 to 4 percent of the available truck drivers in Los Angeles and Ventura Counties and would not adversely affect the truck transportation industry. Traffic conditions near businesses would not change substantially. Business sales and revenues would not change substantially. Infrastructure and municipal services: DOE truck trips would represent 19 to 52 percent of the total shipments from SSFL. Impacts on roads would result in impacts on local government funding and expenses. DOE activities would not require additional services, so there would be no cumulative impacts on other municipal services. Housing availability: Because SSFL workers would likely originate from the region, changes to housing availability are not expected. Disposal facility impacts: Increases in truck traffic from SSFL waste disposal activities are not expected to have a cumulative adverse economic impact on businesses near waste disposal facilities because the maximum number of daily truck trips would be relatively small. DOE estimates that the combined maximum daily truck shipments arriving at a nonhazardous waste facility would be 43.b DOE estimates the maximum daily truck shipments to facilities for other types of waste would be less – 17 at LLW or MLLW facilities, 39 at hazardous waste facilities, and 4 at recycle facilities (see Appendix D).c Summary DOE Contribution to Cumulative Impacts S-95 S-96 Resource Area NASA and Boeing Contribution to Cumulative Impacts Other Contributions to Cumulative Impacts Cumulative Impacts Impacts on minority and lowImpacts on minority and low-income None identified. Impacts on minority and low-income populations income populations would be the populations would be the same as would be the same as those experienced by the same as those experienced by the those experienced by the general general population. Therefore, no disproportionately general population. Therefore, no population. Therefore, no high and adverse cumulative effects on minority and disproportionately high and adverse disproportionately high and adverse low-income populations are expected. effects on minority and low-income effects on minority and low-income populations are expected. populations are expected. Sensitive-aged Impacts on sensitive-aged Impacts on sensitive-aged populations None identified. Cumulative impacts on sensitive-aged populations populations populations would be the same as would be the same as those would be the same as those experienced by the those experienced by the general experienced by the general population. general population. Because there would be no population. No disparate impacts No disparate impacts on sensitive-aged adverse cumulative impacts on members of the (markedly distinct impacts relative populations are expected. public, there would be no disparate cumulative to those on the general population) impacts on sensitive-aged populations. on sensitive-aged populations are expected. ALARA = as low as reasonably achievable; AOC = Administrative Order on Consent for Remediation; BMP = best management practice; Boeing = The Boeing Company; CMWD = Calleguas Municipal Water District; CNEL = community noise equivalent level; dBA = decibels A-weighted; ESAL = equivalent single-axle load; LCF = latent cancer fatality; LLW = low-level radioactive waste; LOS = level of service; LUT = Look-Up Table; MLLW = mixed low-level radioactive waste; NASA = National Aeronautics and Space Administration; NBZ = Northern Buffer Zone; NHPA = National Historic Preservation Act; NRHP = National Register of Historic Places; ROI = region of influence; SRAM = Final Standardized Risk Assessment Methodology Revision 2 Addendum, Santa Susana Field Laboratory, Ventura County, California (MWH 2014). a NASA did not conduct radiological operations in its areas of SSFL; estimated quantities of radioactive waste from NASA remediation are due to naturally occurring isotopes and the LUT values established in accordance with the 2010 NASA Administrative Order on Consent for Remedial Action (DTSC 2010b). b The years in which the maximum number of daily deliveries may occur for different types of waste would be different for DOE, NASA, and Boeing. For example, the maximum daily deliveries of nonhazardous waste from NASA and Boeing combined would likely occur when the number of DOE is shipments small (due to DOE’s planned sequence of activities). Therefore, the combined maximum daily delivery is not the sum of the individual organizations’ maximum daily deliveries. c In accordance with a Transportation Agreement between DOE, NASA, and Boeing (Boeing 2015a), the maximum total number of daily heavy-duty truck round trips from SSFL would be limited to 96. The 96 heavy-duty truck round trips would be split between activities such as trips to disposal facilities or recycle facilities and shipment of backfill to SSFL. Therefore, it is highly unlikely that 96 shipments per day to any single disposal facility would occur. Note: Sums presented in the table may differ from those calculated from table entries due to rounding. Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Environmental justice DOE Contribution to Cumulative Impacts Summary S.12 Conclusions S.12.1 Areas of Potential Controversy As a result of preparing this EIS and based on public comments received during the 2008 and 2014 EIS scoping periods and other ongoing, more-recent community interactions at the site (for example, town hall meetings and DTSC update meetings), the following are areas of controversy that DOE expects will be raised by stakeholders:  Appropriate Cleanup Level – DTSC established AOC LUT values consistent with the 2010 AOC, which requires cleanup to background levels or to levels based on laboratory capabilities. The Cleanup to AOC LUT Values Alternative evaluated in this EIS analyzes the potential impacts that would result from implementation of cleanup to the AOC LUT values. Considering that implementation of the Cleanup to AOC LUT Values Alternative poses technical challenges (for example, requiring 132 individual chemical and radioactive constituents to meet their respective LUT values and clearly distinguishing between contamination and background concentrations); would have significant environmental impacts and higher costs than other soil remediation alternatives (see Appendix J); and would result in minimal reduction in human health risk (see the comparison of background risk to that of Area IV soil in Chapter 4, Section 4.9, and location-specific examples in Appendix J); DOE evaluated two alternatives in this EIS that are based on risk. The Cleanup to Revised LUT Values Alternative uses the same LUT values for radioactive constituents as the Cleanup to AOC LUT Values Alternative, but proposes RBSLs as the revised LUT values for chemicals. These revised LUT values for chemicals were derived from the suburban resident scenario32 evaluated in the SRAM (MWH 2014) and are based on a risk of 1 chance in 1 million for carcinogenic chemicals and a hazard index of 1 for noncarcinogenic chemicals. Under the Cleanup to Revised LUT Values Alternative, the LUT values apply individually to each chemical or radionuclide. The Conservation of Natural Resources Alternative is also based on a suburban residential scenario identified in the SRAM, but applies a risk-assessment approach that evaluates the collective impact of an area (that is, it uses the average concentration of constituents across the area and evaluates the total chemical risk or radiological dose). Under the Conservation of Natural Resources Alternative, DOE would remediate soil to reduce the concentrations of chemical and radioactive constituents to levels protective of human health. Inclusion of these latter alternatives in the analysis allows decision-makers to consider the potential impacts associated with cleanup to the AOC LUT values against risk-based approaches.  Cleanup Completed by 2017 – DOE will not be able to complete cleanup by 2017 under any of the action alternatives. DOE does not consider completion by 2017 to be a reasonable alternative based on the current status of Federal and state environmental reviews (under NEPA and CEQA) or approvals needed before remediation could commence and the amount of work required to complete remediation. After signing the 2010 AOC (DTSC 2010a) and before cleanup could begin, it was necessary to conduct offsite Multiple exposure scenarios were evaluated in the SRAM (MWH 2014). The landowner, Boeing, has stated its intent to maintain its portion of SSFL (which includes Area IV and the NBZ) as undeveloped open space (Boeing 2016b). Regardless, the revised LUT values are conservatively based on the suburban resident scenario direct pathways of inhalation, incidental ingestion, and dermal contact. 32 S-97 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory characterization to establish background values for both chemical (URS 2012) and radioactive (HGL 2011) constituents, perform and document site investigation and characterization of Area IV and the NBZ (HGL 2012a; CDM Smith 2017), and complete soil treatability studies (CDM Smith 2015b). Before DOE can proceed with site remediation, environmental review documentation (including this EIS and the DTSC CEQA program EIR [in preparation]) must be completed. Additional plans and approvals that need to be completed include the SRAIPs for the soil remediation (DOE expects to submit the first of three planned SRAIPs to DTSC at the same time that DTSC issues the final program EIR), RCRA Closure Plans for demolition of regulated buildings (submitted by DOE in 2015 for DTSC approval), and the Corrective Measures Study for groundwater remediation to be submitted by DOE in 2017 for DTSC approval. In addition, DOE and DTSC did not anticipate the volume of soil that would require cleanup (see Table S–3) as a result of the cleanup levels established by the AOC LUTs. An estimated 933,000 cubic yards of soil would be removed under the Cleanup to AOC LUT Values Alternative because it exceeds the AOC LUT values. Under a risk-based approach, that is, under the Cleanup to Revised LUT Values Alternative or Conservation of Natural Resources Alternative, 741,000 more cubic yards of soil (79.4 percent of the total volume of soil that does not meet the AOC LUT values) would be left on site.  Soil Volume Requiring Remediation –To enable DOE to provide a basis for the analysis in this EIS and eventually plan the cleanup activities, an estimate of the volume of soil exceeding the chemical and provisional radiological AOC LUT values was needed. DOE used the analytical results from over 11,000 soil samples (3,542 soil samples taken by EPA for radiological sampling, 5,854 samples taken by DOE for chemical characterization, and 2,259 RFI samples). Based on comparison of the results for each sample with AOC LUT values, DOE estimated that the volume of soil in which one or more chemical or radioactive constituents does not meet the AOC LUT values was about 1,413,000 cubic yards, but acknowledges that due to uncertainties, the volume could range from approximately 1,000,000 to 2,500,000 cubic yards.33  Water Use During Drought Conditions – Cleanup of SSFL Area IV and the NBZ will require a large volume of water. Based on the estimates of soil volumes to be removed, an estimated 4.0 million gallons of water would be needed annually, representing about 0.007 percent of CMWD’s current imported and local water supply, principally to suppress dust generated during remediation actions in accordance with Federal, state, and local regulatory requirements. The Cleanup to AOC LUT Values Alternative would require this water use over a much longer time compared to the other soil remediation action alternatives (10 years compared to a little more than 2 years under the Cleanup to Revised LUT Values Alternative and about 2 years under the Conservation of Natural Resources Alternative). Water use is an important consideration in the comparison of soil remediation alternatives. Any new demand for water is likely to be controversial because of the long-term California DOE estimates the volume of soil that may not meet the AOC LUT values could range from 1,000,000 cubic yards to 2,500,000 cubic yards (see Appendix D). The estimated volume of soil (i.e., 1,413,000 cubic yards) not meeting the AOC LUT values was calculated using a geographic information system evaluation of the vertical and lateral distribution of contamination found during sampling. DOE recognizes that there is uncertainty associated with extrapolating data collected at individual points and therefore identified a range of soil volumes. 33 S-98 Summary drought conditions and the need, as expressed by Governor Brown, to significantly reduce water consumption in the state. Community Acceptance – There is a large community interested in the cleanup of SSFL, including those who live in areas near the site and through which trucks travelling to and from the site would pass. Within that community, there are diverse and divergent opinions regarding the approach to SSFL cleanup and what should be accomplished by the cleanup. As shown by the comments received during scoping, there are varying perspectives among community members regarding how “clean” the site must be upon completion of remediation efforts. - Some members of the community live along transportation routes and will question the necessity for large numbers of trucks transporting waste from SSFL and backfill to SSFL. - Some members of the community are concerned about the selection of a remedy consistent with the AOC LUT values and question whether it is necessary. These members support a risk-based cleanup that is protective of human health and environmentally balanced. - Other members of the community believe SSFL currently serves as a healthy ecosystem with vegetation and wildlife similar to adjacent properties. This segment of the community does not support the Cleanup to AOC LUT Values Alternative, believing the impacts associated with that alternative would inflict unnecessary harm on portions of SSFL that have minimal contamination. - Some members of the community remain concerned about the risk of cancer and other illnesses from hazardous pollutants at the site and support cleaning all of the contamination because that is the best way to ensure that public health is protected. DOE believes the decisions to be supported by this EIS are important and that decisionmakers will need the full range of reasonable alternatives and careful analysis on which to base decisions. S.12.2 Issues to Be Resolved Initiation of Area IV and NBZ remediation is contingent on completing certain regulatory requirements, such as DOE issuing a final EIS and ROD and DTSC issuing a program EIR and decision document, negotiating with DTSC any necessary changes to the 2010 AOC, and addressing the Court Order (Case 3:04-CV-04448-SC, May 2, 2007). Issuance of those documents and/or implementation of the decisions depend on resolution of several issues. The overarching issue related to soil remediation is the cleanup alternative to be selected. Other issues that affect that decision relate to the concentration of chemical and/or radioactive constituents that would be acceptable to leave on site or to be in backfill soil. Resolution of these issues influences the magnitude and feasibility of the cleanup of Area IV and the NBZ. The following issues require resolution:  The 2010 AOC (DTSC 2010a) includes exemptions to protect sensitive biological and cultural resources. The final exemption areas for biological resources will be determined through consultation with the USFWS and CFWS, resulting in a Biological Opinion that would be issued for the proposed action. The final exemption areas for cultural resources will be determined in consultation with SHPO, Santa Ynez Band of Chumash Indians, and the SSFL Sacred Sites Council. For the purposes of this EIS, DOE estimated the proposed S-99 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory biological and cultural exemptions would result in an estimated 330,000 cubic yards of soil that would not be removed. DOE will not know the actual volume of soil that would not be removed until it completes federally required consultations.  Based on completed soil treatability studies, it appears that natural processes would be able to reduce TPH and PAH concentrations adequately to meet AOC LUT values over a long period of time. To support the analysis presented in this EIS, it was assumed that soils with chemical constituents amenable for biological degradation (TPH and PAHs) would be allowed to attenuate on site. The estimated volume of soil at locations with only TPH and PAH contamination is 150,000 cubic yards. Acceptance of this approach to remediation would have to be negotiated with DTSC; if not accepted and the existing AOC LUT values are applied, an estimated 150,000 cubic yards of additional soil would require removal.  An estimated 700,000 cubic yards of backfill would be needed to re-contour the site and restore native vegetation under the Cleanup to AOC LUT Values Alternative. Based on an initial evaluation, no source of backfill has been found that meets the AOC LUT values for concentrations of chemicals.34 Even if an adequate source of backfill were found, DOE is uncertain that the soil would have chemical and biological properties sufficiently similar to SSFL soil for successful restoration of Area IV and NBZ native vegetation. Chances of finding acceptable backfill soil are better under the Cleanup to Revised LUT Values Alternative or Conservation of Natural Resources Alternative because the assumed requirements for concentrations of chemicals in the backfill soil would be less stringent.  Selection of the final remedy for groundwater following this EIS also depends on completion of the RCRA Corrective Measures Study being conducted consistent with the 2007 CO (DTSC 2007). DOE expects to submit its Corrective Measures Study to DTSC in 2017, prior to the DOE ROD for this EIS. S.12.3 Major Conclusions  34 Soil remediation alternatives present a large range of potential environmental impacts, but would result in a small difference in potential human health impacts following cleanup. As presented in Chapter 4, Section 4.9, under the No Action Alternative, the risk to a hypothetical onsite suburban resident from chemicals and/or radionuclides in Area IV and the NBZ are comparable to or less than the risk determined for background soil. Because there is little difference between those risks, there would also be little difference between the risks following cleanup under any of the soil remediation alternatives—risks in all cases would be close to those from exposure to background soil. There would be large differences in other potential impacts during soil remediation, with the largest occurring under the Cleanup to AOC LUT Values Alternative; those under the Cleanup to Revised LUT Values Alternative and Conservation of Natural Resources Alternative would be less. Impacts under the Conservation of Natural Resources Alternative would be the smallest. For example, the amount of land disturbance, which is an indicator of the volume of soil that would be removed and the potential impacts on biological resources, air, traffic, and water use, would be about 130 acres under the Cleanup to AOC LUT Values Alternative; 40 acres under the Cleanup to Revised LUT Values Alternative and 32 acres under the Conservation of Natural Resources Alternative. In support of project implementation DOE would again search for and evaluate sources of backfill. S-100 Summary  The difference in volume estimates for soil remediation between the Cleanup to AOC LUT Values Alternative and either the Cleanup to Revised LUT Values Alternative or Conservation of Natural Resources Alternative is at least 741,000 cubic yards (that is, under the Cleanup to AOC LUT Values Alternative, an additional 741,000 cubic yards of soil would be removed from Area IV and the NBZ). The Cleanup to Revised LUT Values Alternative and the Conservation of Natural Resources Alternative are similar to a risk-based approach that typically has been applied at other DOE cleanup sites35 (determined by an assessment of risk under the projected future land use).  Landfill disposal of 741,000 cubic yards of additional soil under the Cleanup to AOC LUT Values Alternative would result in additional truck trips (55,575 truck round trips for soil removal and 36,245 truck round trips for backfill). Compared to the either the Cleanup to Revised LUT Values Alternative or Conservation of Natural Resources Alternative, this would entail about 8 additional years of truck traffic for hauling soil and backfill. This would be particularly noticeable on Woolsey Canyon Road, as it is the only road into SSFL that is suitable for heavy trucks.  Implementation of the Cleanup to AOC LUT Values Alternative would result in removal of vegetation and wildlife habitat over about 130 acres outside of the proposed exemption areas and an unquantified additional acreage within the proposed exemption areas, causing mortality and disturbance of wildlife within and adjacent to the affected area. By comparison, the Cleanup to Revised LUT Values Alternative would result in removal of vegetation and wildlife habitat over 40 acres, and the Conservation of Natural Resources Alternative over 32 acres.  The soil disturbance caused by remediation would require special measures to accomplish restoration of a self-sustaining native vegetation cover and sources of suitable clean soil for backfill where soil has been removed have not yet been identified. Based on an initial evaluation, DOE has not identified a source of backfill that would meet the AOC LUT values.36 Even if a source of backfill were identified, it is uncertain whether the physical, chemical, and biological characteristics of that soil could support successful site restoration using native vegetation, as discussed in Chapter 4, Section 4.5.1. If backfill is substantially different than the soil originally present on site (e.g., the soil pH [acidity]), it may not support vegetation similar to that present before development of Area IV (e.g., federally and statelisted species such as Braunton’s milk-vetch and Santa Susanna tarplant). With implementation of habitat restoration and revegetation measures, as well as measures to reduce or avoid impacts on wildlife as described in Chapter 6, biological impacts would be reduced, but would not be avoided given the degree of habitat loss that would occur through soil removal and the length of time required to restore vegetation, habitat function, and wildlife populations.  A suburban resident scenario was used as a conservative means of evaluating possible future use for Area IV and the NBZ. The negative incremental risks calculated for the No Action Alternative imply that the concentrations of chemical and radionuclides in soil from siterelated activities are less than the variability of background concentrations of those chemicals and radionuclides. Therefore, the risk of cancer incidence or death from chemicals and/or DOE, in conjunction with its regulators, uses risk assessments that consider the current and potential future use of the land and water resources in making cleanup decisions. The cleanup of the Rocky Flats Plant (DOE, EPA, and CDPHE 2006, DOE 2011b) and the Hanford Site 300 Area (DOE, EPA, and Ecology 2013) are examples of DOE application of risk assessments to site-specific receptors to guide remediation. 36 In support of project implementation, DOE would again search for and evaluate sources of backfill. 35 S-101 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory radionuclides in Area IV and the NBZ are comparable to or less than the risk determined for background soils (see Chapter 4, Section 4.9). However, characterization of Area IV and the NBZ has shown that chemical and radioactive constituents are not spread evenly across Area IV and the NBZ. The areas with concentrations of chemicals exceeding revised chemical LUT values (Figure S–6) or risk-assessment-based concentrations for chemicals and radionuclides (Figure S–7) are smaller than the areas exceeding AOC LUT values (Figure S–5), indicating that these smaller areas are “hot spots.” This implies that the greatest effect on reducing risk to human health would be from focusing on the removal of soil from those locations in Area IV and the NBZ with the highest concentrations of chemical and/or radioactive constituents. Additional soil removal would result in little additional reduction in risk to human health.  S-102 An estimated 4.0 million gallons of water would be required annually to implement any of the soil remediation alternatives. Water use is an important consideration in the comparison of soil remediation alternatives, given the current drought conditions in the State of California and Governor Brown’s proclamation to reduce water usage by 25 percent. The Cleanup to AOC LUT Values Alternative would last 10 years and use 40 million gallons of water, compared to the Cleanup to Revised LUT Values Alternative, which would last a little longer than 2 years and use about 8.3 million gallons, and the Conservation of Natural Resources Alternative, which would last about 2 years and use 8.0 million gallons of water. Summary S.13 References ASTM (ASTM International), 2013, Standard Guide for Greener Cleanups, ASTM E2893-13e1, West Conshohocken, Pennsylvania, November. Boeing (The Boeing Company), 1999, Memorandum from J. Shao, Radiation Safety, to P. Rutherford, “17th Street Drainage Area Radiation Characterization Surveys and Excavation,” January 18. Boeing (The Boeing Company), 2000, Area 4020, MARSSIM Final Status Survey Report, RS-00010, August 31. Boeing (The Boeing Company), 2008, Final Consensus Recommendation on a Site Specific Design Storm for Santa Susana Field Laboratory, Boeing Santa Susana Field Laboratory Stormwater Expert Panel (accessed on June 2, 2015, http://www.boeing.com/assets/pdf/aboutus/environment/ santa_susana/ents/ENTS_Expert_Panel_PublicMeeting_050108.pdf), April 30. Boeing (The Boeing Company), 2015a, Transportation Agreement for the Santa Susana Field Laboratory Ventura County, California Between the Boeing Company (Boeing) and the U.S. Government As Represented by the National Aeronautics and Space Administration (NASA) and the Department of Energy (DOE). Boeing (The Boeing Company), 2015b, Personal communication (email) from D. W. Dassler to J. Wondolleck, CDM Smith, “Re: Responses to DOE EIS questions,” June 11. Boeing (The Boeing Company), 2016a, Santa Susana Field Laboratory, Santa Susana Backgrounder (accessed on January 7, 2016, http://www.boeing.com/resources/boeingdotcom/principles/ environment/pdf/Santa_Susana_backgrounder.pdf). Boeing (The Boeing Company), 2016b, Letter from S. L. Shestag, Director Environment, Santa Susana Site Executive, to S. Kuehl, Supervisor, Third District County of Los Angeles, M. Englander, Los Angeles City Councilman, and F. Pavley, Senator, 27th District Calabasas, “Re: Letter of December 14, 2015 from Supervisor Kuehl, Councilman Englander, and Senator Pavley to Barbara Lee, Director California Department of Toxic Substances Control,” February 22. Burgesser, T., 2015, Memorandum to K. Roberts and J. Wondolleck, An Evaluation of Chemicals of Natural Origin on Reported Total Petroleum Hydrocarbon Concentrations at the Santa Susana Field Laboratory, October 8. CA EO (California Executive Order), 2015, Executive Order B-29-15, April 1. California Energy Commission, 2012, Our Changing Climate 2012 – Vulnerability and Adaptation to the Increasing Risks from Climate Change in California, A Summary Report on the Third Assessment from the California Climate Center (available at http://www.climatechange.ca.gov/adaptation/ third_assessment/), July. CDC (Centers for Disease Control and Prevention), 2014, Sources of Valley Fever (Coccidioidomycosis), Atlanta, Georgia (accessed on May 5, 2015, http://www.cdc.gov/fungal/diseases/coccidioidomycosis/ causes.html), May 14. CDM Smith, 2015a, Final RCRA Facility Investigation (RFI) Groundwater Work Plan, Portions of Area IV under DOE Responsibility, Santa Susana Field Laboratory, Ventura, California, November 9. CDM Smith, 2015b, Soil Treatability Studies, Area IV Santa Susana Field Laboratory, Ventura County, California, Version 2, Denver, Colorado, September. S-103 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory CDM Smith, 2017, Chemical Data Summary Report, Santa Susana Field Laboratory, Ventura County, California, Denver, Colorado, May. CEQ (Council on Environmental Quality), 1981, “Memorandum to Agencies: Forty Most Asked Question’s Concerning CEQ’s National Environmental Policy Act Regulations,” 46 FR 18026, Executive Office of the President, Washington, DC, Federal Register, Vol. 46, March 23, as amended. CH2M Hill, 2008, Group 5 – Central Portion of Areas III and IV, RCRA Facility Investigation Report, Santa Susana Field Laboratory, Ventura County, California, Volume IX, RFI Site Reports, Appendix T, “Systems for Nuclear Auxiliary Power,” Draft, November. CH2M Hill, 2009, Draft Group 3 Remedial Investigation Report at the Santa Susana Field Laboratory, Ventura County, California, May. Chumash (Santa Ynez Band of Chumash Indians), 2014, Personal communication (email) from S. Cohen, Government and Legal Specialist to S. Jennings, U.S. Department of Energy, “Santa Ynez Chumash Comment opposing restriction of EIS alternatives,” March 12. CRWQCB (California Regional Water Quality Control Board), 2007, Letter from D. Hung, Chief, Watershed Regulatory Section, to T. Gallacher, Director, SSFL Safety, Health and Environmental Affairs, The Boeing Company, “National Pollutant Discharge Elimination System Permit (NPDES) (Order No. R4-2007-0055 and Cease and Desist Order (Order No. R4-2007-0056) for the Boeing Company, Santa Susana Field Laboratory, Canoga Park, NPDES No. CA0001309, CI No. 6027,” November. DOE (U.S. Department of Energy), 2003, Final Environmental Assessment for Cleanup and Closure of the Energy Technology Engineering Center, DOE/EA-1345, National Nuclear Security Administration Service Center, Oakland, California (available at http://www.etec.energy.gov/Regulation/ RegDocs/ETECEA.pdf), March. DOE (U.S. Department of Energy), 2009, Scoping Comment Responses for the Environmental Impact Statement for Remediation of Area IV of the Santa Susana Field Laboratory (available at http://www.etec.energy.gov/EIS/Documents/SSFL%20Area%20IV%20Final%20Scoping%20CR D.pdf), September 28. DOE (U.S. Department of Energy), 2010, Community Involvement Plan Area IV Santa Susana Field Laboratory, prepared by CDM Smith and Science Applications International Corporation (available at http://www.etec.energy.gov/EIS/Documents/SSFL_Area_IV_Community_ Involvement_Plan_226-10.pdf), February. DOE (U.S. Department of Energy), 2011a, Administrative Change to DOE O 458.1, Radiation Protection of the Public and the Environment, Change 3 (January 15, 2013), Office of Health, Safety and Security, Washington, DC. DOE (U.S. Department of Energy), 2011b, Corrective Action Decision/Record of Decision Amendment for Rocky Flats Plant (USDOE) Central Operable Unit, Jefferson and Boulder Counties, Colorado, September 19. DOE (U.S. Department of Energy), 2014a, Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Final Scoping Summary Report (available at http://www.etec.energy.gov/Library/Cleanup_and_Characterization/EIS/Final%20Scoping%20 Summary%20Report%20SSFL%20EIS.pdf), August 6. S-104 Summary DOE (U.S. Department of Energy), 2014b, DOE Handbook, Optimizing Radiation Protection of the Public and the Environment for Use with DOE O 458.1, ALARA Requirements, DOE-HDBK-1215-2014, Washington, DC, October. DOE (U.S. Department of Energy), 2015, Executive Order 13693 – Planning for Federal Sustainability in the Next Decade, Memorandum for Distribution from M. Gilbertson, Deputy Assistant Secretary for Site Restoration, Washington, DC, September 10. DOE, EPA, and CDPHE (U.S. Department of Energy, U.S. Environmental Protection Agency, and Colorado Department of Public Health and Environment), 2006, Corrective Action Decision/Record of Decision for Rocky Flats Plant (UDOE) Peripheral Operable Unit and Central Operable Unit, Jefferson and Boulder Counties, Colorado, September. DOE, EPA, and Ecology (U.S. Department of Energy, U.S. Environmental Protection Agency, and Washington State Department of Ecology), 2013, Hanford Site 300 Area Record of Decision for 300-FF-2 and 300-FF-5, and Record of Decision Amendment for 300-FF-1, November. DTSC (State of California Department of Toxic Substances Control), 2007, The State of California Environmental Protection Agency, Department of Toxic Substances Control, The Boeing Company, the National Aeronautics and Space Administration, and the United States Department of Energy, In the Matter of: Santa Susana Field Laboratory, Simi Hills, Ventura County, California, Consent Order for Corrective Action, Docket No. P3-07/08-003, Health and Safety Code Section 25187, August 16. DTSC (State of California Department of Toxic Substances Control), 2009, Interim Advisory for Green Remediation (available at http://www.dtsc.ca.gov/OMF/upload/GRT_Draft_-Advisory_20091217_ac1.pdf), December. DTSC (State of California State of California Department of Toxic Substances Control), 2010a, The State of California Environmental Protection Agency, Department of Toxic Substances Control and the United States Department of Energy, In the Matter of: Santa Susana Field Laboratory, Simi Hills, Ventura County, California, Administrative Order on Consent for Remedial Action, Docket No. HSA-CO 10/11-037, Health and Safety Code Sections 25355.5(a)(1)(B), 58009 and 58010, December 6. DTSC (State of California Department of Toxic Substances Control), 2010b, The State of California Environmental Protection Agency, Department of Toxic Substances Control and the United States National Aeronautics and Space Administration, In the Matter of Santa Susana Field Laboratory, Simi Hills, Ventura County, California, Administrative Order on Consent for Remedial Action, Docket No. HSA-CO 10/11-038, Health and Safety Code Sections 25355.5(a)(1)(B), 58009 and 58010, September 3. DTSC (State of California Department of Toxic Substances Control), 2013, Chemical Look-Up Table Technical Memorandum, Santa Susana Field Laboratory, Ventura, California, June 11. EPA (U.S. Environmental Protection Agency), 2009, Principles for Greener Cleanups, Office of Solid Waste and Emergency Response, Washington, DC, August 27. EPA (U.S. Environmental Protection Agency), 2015a, “Integrated Risk Information System” (available at http://www2.epa.gov/iris). EPA (U.S. Environmental Protection Agency), 2015b, “Regional Screening Levels (RSLs) – Generic Tables (November 2015),” November. Geosyntec, 2012, 2012 BMP Plan Addendum Santa Susana Site, Ventura County, California, prepared with the Santa Susana Site Surface Water Expert Panel, Los Angeles, California, September 28. S-105 Draft Environmental Impact Statement for Remediation of Area IV and the Northern Buffer Zone of the Santa Susana Field Laboratory Haley and Aldrich (Haley & Aldrich, Inc.), 2010, Site-Wide Water Quality Sampling and Analysis Plan, Santa Susana Field Laboratory, Ventura County, California, Revision 1, Tucson, Arizona, December. HESIS (Hazard Evaluation System and Information Service), 2013, Fact sheet: Preventing WorkRelated Coccidioidomycosis (Valley Fever), California Department of Public Health, California Department of Industrial Relations, Richmond, California (available at https://www.cdph.ca.gov/ programs/hesis/Documents/CocciFact.pdf), June. HGL (HydroGeoLogic, Inc.), 2011, Final Radiological Background Study Report, Santa Susana Field Laboratory, Ventura County, California, prepared for the U.S. Environmental Protection Agency, Region 9, October. HGL (HydroGeoLogic, Inc.), 2012a, 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 the U.S. Environmental Protection Agency, Region 9, December. HGL (HydroGeoLogic, Inc.), 2012b, Final Technical Memorandum Look-up Table Recommendations, Santa Susana Field Laboratory Area IV Radiological Study, prepared for the U.S. Environmental Protection Agency, Region 9, November 27. ICRP (International Commission on Radiological Protection), 1977, Recommendations of the International Commission on Radiological Protection, ICRP Publication 26, Annals of the ICRP, Vol. 1 (3). ICRP (International Commission on Radiological Protection), 1983, Cost-Benefit Analysis in the Optimization of Radiation Protection, ICRP Publication 37, Annals of the ICRP, Vol. 10 No 2/3. IPCC (Intergovernmental Panel on Climate Change), 2013, Climate Change 2013 - The Physical Science Basis, Working Group I Contribution to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge University Press, New York, New York (available at http://www.climatechange2013.org/images/report/WG1AR5_ALL_FINAL.pdf). LA (City of Los Angeles), 2006, L.A. CEQA Thresholds Guide, Your Resource for Preparing CEQA Analyses in Los Angeles. Matsumoto, M. R., and J. Martin, 2015, Summary Report: Santa Susana Field Laboratory (SSFL) Soil Partitioning Treatability Study, University of California, Riverside, California, May. MWH (MWH Americas, Inc.), 2006, Group 6 – Northeastern Portion of Area IV RCRA Facility Investigation Report, Santa Susana Field Laboratory, Ventura County, California, Vol. 1, Arcadia, California, September. MWH (MWH Americas, Inc.), 2007, Group 8 – Western Portion of Area IV, RCRA Facility Investigation Report, Santa Susana Field Laboratory, Ventura County, California, Arcadia, California, September. MWH (MWH Americas, Inc.), 2009, Group 7 – Northern Portion of Area IV RCRA Facility Investigation Report, Santa Susana Field Laboratory, Ventura County, California, Vol. 1, Arcadia, California, June. MWH (MWH Americas, Inc.), 2012, Stormwater Pollution Prevention Plan for the Santa Susana Site, Revision 7, prepared for The Boeing Company, Santa Susana Site, Arcadia, California, October. MWH (MWH Americas, Inc.), 2014, Final Standardized Risk Assessment Methodology Revision 2 Addendum, Santa Susana Field Laboratory, Ventura County, California, August. S-106 Summary NAHC (Native American Heritage Commission), 2014, Native American Heritage Commission Sacred Lands Inventory, Santa Susana Sacred Sites and Traditional Cultural Landscape. Nelson, Y. M., K. Croyle, M. Billings, and M. Poltorak, 2015a, Natural Attenuation Study for the Santa Susana Field Laboratory: Final Report, California Polytechnic State University, San Luis Obispo, California, April 27. Nelson, Y. M., M. Poltorak, M. Curto, P. Waldburger, A. Koivunen, and D. Dowd, 2015b, Phytoremediation Study for the Santa Susana Field Laboratory Final Report, California Polytechnic State University, San Luis Obispo, California, April 16. Nelson, Y. M., M. Billings, K. Croyle, C. Kitts, and A. Hamrick, 2015c, Bioremediation Study for the Santa Susana Field Laboratory Final Report, California Polytechnic State University, San Luis Obispo, California, May 7. Nelson, Y. M., S. Cronin, K. Cochran, and A. Varni, 2015d, Chemical Characterization of Residual Fuel Hydrocarbons in Soils at the Santa Susana Field Laboratory, Final Report, California Polytechnic State University, San Luis Obispo, California, July 31. New York Times, 2016, In Sharp Reversal, California Suspends Water Restrictions, May 18. North Wind (North Wind Incorporated), 2014, Personal communication (email) from B. Frazee to S. Jennings U.S. Department of Energy, “ETEC D&D Waste Quantity Estimates,” November 10. P2 Solutions, 2009, Report on Community Interviews, Community Concerns and Preferences for Public Participation in Cleanup of Area IV, Santa Susana Field Laboratory (available at http://www.etec.energy.gov/EIS/Documents/Community_Interviews.pdf), Idaho Falls, Idaho, February. SFWQCB (San Francisco Bay Regional Water Quality Control Board), 2013, 2013 Tier 1 ESLs, California Environmental Protection Agency, Water Boards, Oakland, California, December. SWRCB (State Water Resources Control Board), 2016, California Drought, State Water Board Adopts ‘Stress Test’ Approach to Water Conservation Regulation, May 18. URS (URS Corporation), 2012, Final Chemical Soil Background Study Report, Santa Susana Field Laboratory, Ventura County, California, prepared for the California Environmental Protection Agency, Department of Toxic Substances Control, Los Angeles, California, December. USGCRP (U.S. Global Change Research Program), 2014, Climate Change Impacts in the United States, U.S. National Climate Assessment, Washington, DC (available at http://www.globalchange.gov/ nca3-downloads-materials), May. S-107