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HomeMy WebLinkAboutCC AG PKT 2004-08-09 #MAGENDA REPORT DATE: August 9, 2004 TO: Honorable Mayor and City Council THRU: John B. Bahorski, City Manager FROM: Lee Whittenberg, Director of Development Services SUBJECT: APPROVAL OF CITY RESPONSE LETTER RE: DRAFT PROJECT CLOSEOUT REPORT — NON -TIME CRITICAL REMOVAL ACTION, INSTALLATION RESTORATION PROGRAM SITE 7 (STATION LANDFILL) and SITE 4 (PERIMETER ROAD AOPCS 1A AND 2A), NAVAL WEAPONS STATION SUMMARY OF REOUEST: Authorize Mayor to sign proposed response letter, with any additional comments determined_ appropriate. Instruct Staff to forward approved letter to Environmental Quality Control Board and Archaeological Advisory Committee. * Receive and File Staff Report, BACKGROUND: The Department of the Navy (DON) has completed the above referenced document, which describes in detail the completion of the installation restoration activities at IR Site 7 (Station Iandfill) and IR Site 4 (Perimeter Road AOPCs I and 2A), and is requesting any comments on the document be submitted by August 17, 2004. The removal action was completed in accordance with the approved "Work Plan" Proposed City Comment Letter: On July 28, 2004, the EQCB considered a staff report regarding this removal action and approved the draft comment letter as prepared by staff. The comment letter extends the appreciation of the City in undertaking this activity in a manner to provide the highest level of protection to the residents of Sea] Beach and Huntington Beach. On October 22, 2003 the EQCB commented on a "Draft Project Work Plan", which described the procedures by which the non -time critical removal action project at the subject sites would be undertaken. Between 1995 and 2004 the City has reviewed and commented Agenda Item Z.\hly Documents \NAVWPSTA \Site 7 Draft Project Closeout Report CC SR.doc \LW\07 -28-04 Cith, Council Staff Report re: Draft Project Closeout Report - Non -Time Critical Removal Action, - Gtstallation Restoration Program Site 7 (Station Landfill) and Site 4 (Perimeter Road .40PCs IA And 2A) Naval Meapons Station July 28, 2004 on 21 separate documents relating to the site characterization and removal actions at the subject sites. Overview of Removal Project: The following activities were completed in accordance with the approved "Work Plan" and the activities were supported by the EQCB and the City Council by previous letters to the Navy and Department of Toxic Substances Control. At IRP Site 7 Area 1, landfill cover repair activities began on December 8, 2003 and were completed on April 5, 2004. Approximately 15,000 cubic yards of clean fill material was placed in Area 1 to construct the landfill cover to the minimum requires thickness of 2 feet and to create to topography according to the approved grading plan. Surficial debris removal from Areas 3, 4 and 6 was performed from December 8 to December 16, 2003. In Area 5, excavation of the two trenches and subsequent backfilling with clean fill began on February 17, 2004 and was completed by February 23, 2004. Removal activities to Areas 3, 4, 5, and 6 produced approximately 1,300 tons of debris. This debris was temporarily stockpiled on site pending sampling and characterization and was subsequently transported off site as non - hazardous waste. Excavation of lead - impacted soils from IRP Site 4 AOPCs IA and 2A commenced on January 24, 2004. Soil excavation and confirmation sampling was completed on March 8, 2004. A total of 7,800 tons of lead- impacted soil was excavated and removed. Based on confirmation sampling for waste classification purposes, the contaminated soil was classified as non - Resource Conservation and Recovery Act hazardous waste. The excavated soil was transported to an approved disposal facility in Kettleman City. Upon final grading of all sites, revegetation was performed in accordance with a plan approved by the U. S. Fish and Wildlife Service. The project was completed in accordance with the approved "Work Plan" and in accordance with the mitigation measures established by the Department of Toxic Substance Control through the approved Negative Declaration for compliance with the California Environmental Quality Act. The cost of this removal action was $1,953,500.00. Document Availability: The subject document is available for review at the Department of Development Services, City Hall, 211 Eighth Street. FISCAL IMPACT: Site 7 Draft Pmject Closmut Report CC SR 2 ON Council StatfReport re: Draft Project Closeout Report Non -Time Critical Removal Action. - Installation Restoration Program Site 7 (Station Lrindfill) and Site 4 (Perimeter Road AOPCs IA And 2A) Naval Weapons Station July 28, 2004 None. All costs of the Installation Restoration program are funded by the Department of Navy. RECOMMENDATION: Authorize Mayor to sign proposed response letter, with any additional comments determined appropriate. Instruct Staff to forward approved letter to Environmental Quality Control Board and Archaeological Advisory Committee. Receive and File Staff Report. e Whittenberg ' Director of Development Service Attachments: (2) Attachment 1: Draft Comment Letter to Naval Weapons Station, Seal Beach Re: "Draft Project Closeout Report, Non -Time Critical Removal Action, Installation Restoration Program Site 7 (Station Land/111) And Site 4 (Perimeter Road AOPCs IA And 2A), Naval Weapons Station, Seal Beach ", Southwest Division, Naval Facilities Engineering Command, Dated June 18, 2004 Attachment 2: "Draft Project Closeout Report — Non -Time Critical Removal Action, Installation Restoration Program Site 7 (Station Landfill) and Site 4 (Perimeter Road AOPCs IA And 2A), Naval Weapons Station, Seal Beach ", Southwest Division, Naval Facilities Engineering Command, dated June 18, 2004 Note: Entire document not provided due to length, 188 pages plus a CD -ROM. Provided are the Title Page, Executive Summary, Table of Contents, List of Tables, List of Figures, and Appendix D — "Photographic Log of the Removal Activities ". Site 7 Draft Pmject Closmut Report.CC SR 3 sl. City Council StafReport re: Draft Project Closeout Report - Non -Time Critical Removal Action, - Installation Restoration Program Site 7 (Station Landfill) and Site 4 (Perimeter Road AOPCs 1.4 And 2A) Naval Weapons Station Juh, 28, 2004 ATTACHMENT 1 DRAFT COMMENT LETTER TO WEAPONS SUPPORT FACILITY, SEAL BEACH RE: "DRAFT PROJECT CLOSEOUT REPORT, NON -TIME CRITICAL REMOVAL ACTION, INSTALLATION RESTORATION PROGRAM SITE 7 (STATION LANDFILL) AND SITE 4 (PERIMETER ROAD AOPCS IA AND 2A), NAVAL WEAPONS STATION, SEAL BEACH", SOUTHWEST DIVISION, NAVAL FACILITIES ENGINEERING COMMAND, DATED JUNE 18, 2004 Site 7 Draft Project Closeout Report.CC SR 4 City Council StajfReport re: Draft Project Closeout Report - Non- Time Critical Reneoval Action, -Installation Restoration Program Site 7 (Station Landfill) and Site 4 (Perimeter Road AOPCs IA And 2A) August 9, 2004 Department of Navy Weapons Support Facility, Seal Beach Attn: Pei -Fen Tamashiro, Installation Restoration Coordinator 800 Seal Beach Boulevard Seal Beach, CA 90740 -5000 Dear Ms. Tamashiro: Naval Weapons Station Juh, 28, 2004 SUBJECT: CITY OF SEAL BEACH COMMENTS RE: "DRAFT PROJECT CLOSEOUT REPORT, NON -TIME CRITICAL REMOVAL ACTION, INSTALLATION RESTORATION PROGRAM SITE 7 (STATION LANDFILL) AND SITE 4 (PERIMETER ROAD AOPCS IA AND 2A), NAVAL WEAPONS STATION, SEAL BEACH" The City of Seal Beach has reviewed the above referenced document and concurs with the findings and conclusions of the report. On October 22, 2003 the EQCB commented on a "Draft Project Work Plan", which described the procedures by which the non -time critical removal action project at the subject sites would be undertaken. Between 1995 and 2004 the City has reviewed and commented on 21 separate documents relating to the site characterization and removal actions at the subject sites. The City appreciates the recognition of our concerns regarding the determination of appropriate characterization methodologies, target clean -up goals, and other technical concerns regarding the proposed site remediation and removal processes that have been expressed over the past 9 years regarding these sites. The City appreciates the setting forth and implementation of adequate mitigation measures to address these concerns. The City of Seal Beach extends its sincere appreciation to the Naval Weapons Station and the Department of the Navy in undertaking this activity in a manner to provide the highest level of protection to the residents of Seal Beach, Huntington Beach, and to the employees of the Naval Weapons Station. Site 7 Draft Protect Closeout Report.CC SR Ciro Council Staff Report re: Draft Project Closeout Report - Non -Time Critical Removal Action, - Installation Restoration Program Site 7 (Station Landfill) and Site 4 (Perimeter Road AOPCs IA And 2A) Naval Weapons Station July 28, 2004 Thank you for allowing us to comment on the proposed "Draft Closeout Report" at IR Sites 7 and 4. If you have any questions or require further information, please contact Mr. Lee Whittenberg, Director of Development Services Department, (562) 431 -2527, extension 313, at your earliest convenience. He will be able to respond to any additional questions that you may have regarding this matter. Sincerely, 1 Paul Yost Mayor City of Seal Beach Mario Voce Chairperson Environmental Quality Control Board cc: City Council Environmental Quality Control Board Archaeological Advisory Committee City Manager Director of Development Services Site 7 Draft Project Closeout Report CC SR City Council Staff Report re: Draft Project Closeout Report - Non -Time Critical Removal Action, - Installation Restoration Program Site 7 (Station Landfill) and Site 4 (Perimeter Road AOPCr 1.4 And 2A) Naval Weapons Station Ali; 28, 2004 ATTACHMENT 2 "DRAFT PROJECT CLOSEOUT REPORT - NON-TIME CRITICAL REMOVAL ACTION, INSTALLATION RESTORATION PROGRAM SITE 7 (STATION LANDFILL) AND SITE 4 (PERIMETER ROAD AOPCS IA AND 2A), NAVAL WEAPONS STATION, SEAL BEACH", SOUTHWEST DIVISION, NAVAL FACILITIES ENGINEERING COMMAND, DATED JUNE 18, 2004 NOTE: ENTIRE DOCUMENT NOT PROVIDED DUE TO LENGTH, 188 PAGES PLUS A CD -ROM. PROVIDED ARE THE TITLE PAGE, EXECUTIVE SUMMARY, TABLE OF CONTENTS, LIST OF TABLES, LIST OF FIGURES, AND APPENDIX D - "PHOTOGRAPHIC LOG OF THE REMOVAL ACTIVITIES". Site 7 Draft Project Closeout Report CC SR 7 Southwest Division Naval Facilities Engineering C ^mmand Contracts Department ` 1220 Pacific Highway, Building 127, Room 112 San Diego, CA 92132 -5190 CONTRACT No. N68711 -98 -D -5713 CTO No. 0023 DRAFT PROJECT CLOSEOUT REPORT Revision 0 June 18, 2004 NON - TIME- CRITICAL REMOVAL ACTION INSTALLATION RESTORATION PROGRAM SITE 7 (STATION LANDFILL) AND SITE 4 (PERIMETER ROAD AOPCs 1A AND 2A) NAVAL WEAPONS STATION SEAL BEACH SEAL BEACH, CALIFORNIA DCN: FWSD- RAC -04 -2056 Prepared by: TETRATECH F`v% i.NCI 1230 Columbia Street, Suite 500 San Diego, CA 92101 amlet H. i� -damp rs uan Projecthlanager Jamshid Sadegl pour, 3S.D.,9 .E. Deputy Program Manager CI Y OF SEAL SEACH JU14 j 1 Zll!14 L_F-.,RT' --NTOF DE \'EtC' hf: r SERVICES EXECUTIVE SUMMARY This Project Closeout Report describes the implementation of a Non - Time - Critical Removal Action (NTCRA) at Installation Restoration Program (IRP) Site 7 and Site 4 Areas of Potential Concern (AOPCs) IA and 2A, also referred to as the Station Landfill and the Perimeter Road, respectively, at Naval Weapons Station (NAVWPNSTA) Seal Beach, Seal Beach, California (Figures 1 -1 and 1 -2). The Department of the Navy (DON) previously determined (upon review of the operational histories of these sites and site - specific investigative data) that these sites contained surficial and buried waste, waste debris, and contaminated soil requiring a response action. The DON initiated the NTCRA at IRP Site 7 and IRP Site 4 AOPCs IA and 2A to minimize potential threats to Inman health and the surrounding environment (Figures 1 -1, 1 -2, and 1 -3). This decision was documented in the joint IRP Site 7 and IRP Site 4 AOPCs IA and 2A .4ction Afemorandum [Al JINon- Time - Critical Remedial Action Plan [RAP] at the Aural ifeapons Station Seal Beach, California, Site 7 and Site 4 AOPCs IA and 2.4 (CH2M Hill, 2004). The removal action at IRP Site 4 specifically addressed the removal of soil contaminated with lead (hot spots) in AOPCs 1.A and 2A at this site. The removal action for IRP Site 4 AOPCs IA and 2A was conducted because lead "hot spots" were detected in soil with concentrations that were an ecological concern [Bechtel National, Inc. (BNI), 2001]. Due to the proximity to IRP Site 7, IRP Site 4 AOPCs IA and 2A were considered extensions of IRP Site 7 (CH21A Hill, 2004) and were therefore included in this NTCRA (Figure 1 -2). Under the DON's directive, Tetra Tech FW, hic. (TtFIV), as General Contractor, conducted the removal action at the site under Remedial Action Contract No. N68711 -98 -D -5713. The removal action was conducted in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and National Oil and Hazardous Substances Pollution Contingency Plan (NCP) requirements. IRP Site 7 consists of six distinctive areas (designated as Areas 1 through 6) totaling approximately 33 acres located near the southern boundary of NAN7WPNSTA Seal Beach and at the eastern boundary of the Seal Beach National Wildlife Refuge (SBN \VR) (Figure 1 -3). Landfill activities were reportedly conducted at the site from approximately 1955 to 1973. A soil cover consisting of a nonuniform, nonengineered soil of variable thickness overlying IRP Site 7 was present that ranged in thickness from zero to 2 feet, with refuse exposed at the ground surface in some areas. Areas of debris associated with past landfill operations at IRP Site 7 were identified and designated as Areas I to 6, and briefly described below: D4 ^_056D&iolClosenutRpl Stles4S.7 ES -1 Draft Project Closeout Report NTCRA IFJ Site 7 and Site 4 Naval Weapons Station Seel Beech DCN PNISD- RAC-04 -7056 CTO No 0023, Revtnan 0, 0&1 VO4 • Area 1 lies in the northeast portion of the site. Itcoyers approximately 8 acres. Most of -" the waste disposal and landfilling activities took place in Area l in a series o? Llined trenches lying in an east -west orientation [Naval Energy and Enviromnental Support Activity (NEESA), 1955]. Exploration dining a supplemental characterization indicated that the depth of the debris varied between 5.5 and 9 feet below ground surface (bgs), with an average depth of 6.4 feet bas [Southwest Division Naval Facilities Engineering Corm-nand (SvVDIV), 1999c]. • Area 2 lies along the southern boundary of the site adjacent to Perimeter Road. It is Probably a single, continuous trench approximately 600 feet long by 40 feet wide (approximately 0.6 acres). The average depth of debris is about 7.5 feet bgs. • Area 3 is an irregularly shaped area and lies in the northwest portion of IRP Site 7. It is approximately 1 acre. Surficially scattered, rusted, metal debris littered Area 3. • Area 4 is an irregularly shaped area of approximately 1 acre and lies in the northwest portion of IRP Site 7, southeast of Area 3. It was also littered with surficially scattered, rusted, metal debris. • Area 5 borders the eastern shoreline of Perimeter Pond and lies between Perimeter Pond and East Pond (Figure 1 -3) and consisted of two north- south- oriented trenches, with a portion of the western trench exposed to Perimeter Pond. Area 5 covers approximately 0.7 acres and had an average bottom debris depth of 9 feet (SWDIV, 1999c). • Area 6 lies to the southeast of Area 5. This area is similar to Areas 3 and 4 in that the debris found in this area appears to be surficial only. This area is irregular in shape and occupies approximately 0.1 acres. IRP Site 4 AOPCs lA and 2A consist of a 5,400- feet -long by 100- feet -wide unpaved shoulder adjacent to Perimeter Road, along the southern boundary of NAV\VPNSTA Seal Beach, and directly south and adjacent to IRP Site 7 (Figures 2 -1 and 2 -2). Based on the findings and conclusions for soil at IRP Site 4 AOPCs IA and 2A, these areas were identified as containing several potential locations where elevated lead was detected due to oiling of Perimeter Road for dust control (S\VDIV, 1995). Unkmown quantities of waste oil were sprayed over the perimeter roads for dust control. An estimated 40,000 gallons of waste oil was applied over a 1 -year period on 12 miles of road (NEESA, 1985; S\VDIV, 199011). Information from previous investigations indicated that elevated lead concentrations were detected to a depth of at least 2.5 feet (S\VDIV, 1990b: BNI, 2001). Four risk assessments have been performed using data, collected frrnn IRP Site 7. Based on the Human Health Risk Assessment (HHRA) and Ecological Risk Assessment (ERA); it was concluded that the nsk from chemicals of potential concern (COPCs) to human health and ecological receptors are marginal (S \VDIV, 1995; 1999a: and 2000b). The most significant possible risk was determined to be to aquatic ecological receptors in Perimeter Pond. Due to the siamificant threats to ecological receptors at IRP Site 7, a removal action was warranted. 042050D1 N o,C1oseou1Rpl S,WA&7 ES -2 Drag Proieq Closeom Report NTCRA IRP Si(, 1 and Ste 4 Naeal Weapons Sworn Seal Reach DCN FWSD- RAC-04- 2056 CTO No 0023, Rerisun 0, 06/16 04 Human exposure to IRP Site 4 AOPCs lA and 2A is considered very limited due to their »� roxi:: ity to the SBNWR. Department of Toxic Substauces`Control (DTSC) also statedtthat the human health risk did not appear to be an issue, particularly due to the low exposure related to intermittent travel on Perimeter Road (BNI, 2001). Therefore, the decision to conduct a removal action for IRP Site 4 AOPCs I and 2A was based on potential exposure to ecological receptors only. The following Removal Action Objectives (RAOs) were developed for IRP Site 7 and IRP Site 4 AOPCs IA and 2A based on CERCLA, NCP, the risk assessment presented in the Final Engineering Evaluation/Cost Analysis (EE /CA) for IRP Site 7 (CH2M Hill, 2002a), the Final Addendum to the EE /CA for IRP Site 7, and IRP Site 4 AOPCs IA and 2A (CH2M Hill, 2003a), and applicable or relevant and appropriate requirement (ARARs): IRP Site 7 • Reduce the potential for exposure of ecological receptors to landfill waste and potentially contaminated soil by increasing separation and /or eliminating exposure pathways (for example, water seeps) of wastes to human and ecological receptors. • Restore habitat that is compatible with the SBNWR habitat. • Minimize impact to Netlands and improve conditions of remaining wetlands, to the extent practicable. • Control surface water runoff and reduce the potential for erosion of the landfill surface. • Comply with chemical - specific ARARs where exceedances have occurred due to waste releases. IRP Site 4 AOPCs IA and 2A • Minimize further migration of lead in surface soil. • Reduce risk to ecological receptors from lead - contaminated soil to acceptable levels. The recommended removal action for Area 1 at IRP Site 7 presented in the Final EE /CA (CH2M Hill, 2002a) involved repair of the existing soil cover by placing an additional cover layer in areas where waste was exposed or there was cover thickness deficiency. The recommended removal action for Areas 3, 4, and 6 involved removal, of the surface debris from the top I to 2 feet of soil in Areas ; and 4, and on the surface in Area 6. The removal action recommended for Area 6 -was to excavate and remove the buried debris in two north- south - oriented trenches, disposal of the excavated waste. and backfillina with clean soil. No target cleanup goals (TCGs) were developed for the recommended removal action at IRP Site 7. Since there were no 042056Dt R oIC lose outRpi Snes4S7 ES -3 D,ah Rotect Closeout Repon NTCRA IRP Site , and Sve 4 Naval Weapon=. Sta4on Seal Peach DCN FN'SD.RAC -04 -2056 CTU No 0073, Revaion 0, 06/16/04 definitive risk -based cleanup coals for sediment, limits of excavation were to be deternained by visual inspection and then backfilling with clean fine - grained soils. Groundwater at IRP Site 7 is at approximately 3 to 5 feet bgs (CH2M Hill, 2002b). Although, based on previous investigations, groundwater at IRP Site 7 appears to be not impacted, additional groundwater monitoring will be performed at this site by a different DON consultant under a separate contract. For IRP Site 4 AOPCs 1 and 2A, the soil TCG for lead of 600 milligrams per kilogram (mg/kg) was established based on the risks to representative site - specific ecological receptors, which include harvest mouse, ground squirrel, skunk; and robin (CH21\4 Hill, 200' )a). This is in addition to an area -wide arithmetic average TCG of less than 100 mg/kg for lead in soils remaining at the IRP Site 4 AOPCs I and 2A, at the conclusion of the removal action. The arithmetic average of lead concentrations in soil is the total of soil sample lead concentrations results for the pre - excavation characterization samples and the verification samples (only the total of those results that were less than 600 mg/kg), divided by the total number of the results. TtFW was directed by the DON to implement the recommended removal action at IRP Site 7 and Site 4 AOPCs IA and 2A. A Final Project Work Plan (Work Plan) was prepared by TtFW on January 23, 2004 (TtF`W, 2004a), which included the detailed description of various activities for the implementation and execution of the removal action. The Final Work Plan was subsequently approved by the regulatory agencies. The objective of removal action in Area 1 was to repair the existing landfill soil cover and to provide a minimum thickness of 2 feet of cover over waste. This will prevent direct contact of wildlife with buried waste and eliminate the potential migration of contamination through windblown dust and surface runoff. No removal activities were conducted by TtF \W in Area 2. The objectives for the removal activities in .Areas 3, 4, and 6 were to remove the surface debris and to perform a geophysical survey in Areas 3 and 4 (Figure 4 -3) to assess the potential for any subsurface debris (based on historical data, Area 6 was not suspected to contain subsurface debris). The objective for the removal activities in Area 5 was to excavate two north- south - oriented disposal trenches (east trench and west trench) containing buried metallic debris and trash, and off -site disposal of the removed waste. There were no chemicals of concern associated with Area 5 of IRP Site 7 and therefore no TCGs to achieve. For this reason, confirmation sampling was not conducted following the removal of debris in Area 5. The removal alternative selected for IRP Site 4 .AOPCs IA and 2A involved pre - excavation soil sampling to determine the extent of lead - impacted soil, excavation and off -site disposal of the lead- 042056DrProlCloseoutRpt SIte54&1 7 ES -4 Diafi Pmlecl Closeout Rep= NTCRP, 1RP Site , and Site 4 Nai al Weapons Siauou Seal Beach DCN FWSD- RAC -044- 1056 CTO No 0023, Remson O. On /IS /O4 impacted soil, and confirmation sampling to ensure that soil with lead concentrations exceeding the _mCG as been removed. The impacted soil would be disposed at an approved landfill -and the excavation backfilled with clean fill. TtFW conducted a number of preparatory activities at the site prior to excavation of the contaminated soil. A geophysical survey was performed on December 3, 2003, to assist in locating and marking any underground utilities within the limits of excavation at IRP Site 7 and Site 4 AOPCs IA and 2A. At IRP Site 7, an initial land survey was performed (December 5 through December 10, 2003) to assist in establishing the existing surface elevations of Area 1, to provide data for the design of the post - cover - repair grading plan for Area 1, and to delineate the limits of Areas 1 through 6. At IRP Site 4 AOPCs IA and 2A, an initial land survey was performed (December 2 through December 9, 2003) to delineate a network of contiguous gr d cells across the limits of AOPCs IA and 2A and to establish pre - excavation soil sample points within each grid cell. At IRP Site -7 Area 1, landfill cover repair activities began on December 8, 2003, and were completed on April 5, 2004. Approximately 15,000 cubic yards or approximately 22,500 tons of clean fill material were placed in Area I to construct the landfill cover to the minimum required thickness of 2 feet and to create the topography according to the approved grading plan. Surficial debris removal from Areas 3, 4, and 6 was performed from December 8 to December 16, 2003. ht Area 5, excavation of the two trenches and subsequent backfilling with clean fill began on February 17, 2004, and was completed by February 27, 2004. Removal activities in Areas 3, 4, 5, and 6 produced approximately 1,300 tons of debris. This debris was temporarily stockpiled on site pending sampling and characterization and was subsequently transported off site as non - hazardous waste. Based on pre - excavation sample results, excavation of lead - impacted soil from IRP Site 4 AOPCs IA and 2A commenced on January 24, 2004. After excavating the soil, confirmation samples were collected from the floor and sidewalls of each grid cell to ensure that the removal action satisfied the TCG of 600 mg/kg for lead and that the area -wide arithmetic mean for lead in soil remaining at the site at the conclusion of the removal action be less than 100 mg/kg. Soil with concentrations of lead above the TCG was further excavated in 6 -inch lifts, follo'A'ed by additional confirmation sampling, until the TCG was achieved. A total of 245 confirmation samples were collected and analyzed. Laboratory results of lead concentrations in the final confirmation soil samples ranged from 2.9 mg/kg to 590 mg/kg. The final mean concentration for lead in soil remaining in AOPCs IA and 2A was 63.7 mg/kg. Soil excavation and confirmation sampling activities were completed in IRP Site 4 AOPCs 1 A and 2A on March 8, 2004. A total of 7,800 tons of lead - impacted soil was excavated and removed from IRP Site 4 AOPCs IA and 2A. Excavated material was temporarily stockpiled on site. The stockpiled soil 04205 6D Pi olCloseoutRpt Snes4 &7 ES -5 Draft Pinled Closeout Report NTCR4 IRP Sa 7 and sire 4 Naval Weapons subon Seal beach DCN FUSD- RAC -04 -2056 CTO No 00 ^3, R,ision 0, 06/)8/04 was sampled for waste classification purposes. Based on the, test results, the contaminated soil was classified as non - Resource Conservation and Recovery Aci hazardous waste. From March 15 to March 25, 2004, the lead - impacted soil and non- hazardous soil /debris were loaded onto a total of 406 24 -ton capacity end -dump trucks or trailer trucks and transported off site to the Chemical Waste Management, Inc. (CWM) disposal facility located in Kettleman City, California. This CWM disposal facility is a Resource Conservation and Recovery Act (RCRA)- permitted and CERCLA- approved disposal facility. Trucks containing lead - impacted soil were completely covered with a tarp prior to leaving the site. Approximately 5,200 cubic yards or approximately 7,800 tons of clean fill material were used to backfill the excavated grid cells in IRP Site 4 AOPCs I and 2A. Approximately 1,000 cubic yards or 1,500 tons of clean soil were used to backfill the excavated trenches at Area 5. A total of approximately 31;800 tons of clean soil were used for the landfill cover repair, backfill of Area 5 excavated trenches, and backfill of the excavated grid cells at IRP Site 4 AOPCs I and 2A. Approximately 23,800 tons of dredged sediment soil stockpiled at the NAVWPNSTA wharf were used as backfill material at IRP Site 4 AOPCs 1 A and 2A for the repair of the landfill cover at Area 1 and for backfilling the excavated trenches at Area 5. In addition, approximately 640 tons of clean soil were imported from an off -site borrow source and used as fill material at IRP Site 7 Area 1. Approximately 5,200 tons of clean soil generated from the removal action at IRP Site 5 and stockpiled near IRP Site 7 were used as topsoil, along with approximately 2,200 tons of imported topsoil material obtained from an off -site borrow source. Revegetation was performed at IRP Site 7 and Site 4 AOPC IA at the conclusion of the removal action. Various native seed mixes approved by the SBNNVR Manager were used to facilitate the regrowth of native vegetation in the disturbed areas. Additional plant plugs will be provided to the United States Fish and Wildlife Service (USFWS) at a later date for additional site restoration at AOPC 2A. Dust levels were visually monitored during the NTCRA at IRP Site 7 and Site 4 AOPCs I and 2A and were controlled using water application. Dust control was implemented on a regular basis for the duration of the project. Based on the results of the landfill cover repair and surficial and Buried debris removal in IRP Site 7 and the confirmation samples collected from IRP Site 4 AOPCs IA and 2A following the excavation activities, the RAOs developed in the Final EE /CA for IRP Site 7 (CH2M Hill. 2002a) and the Final Addendum to the EE /CA for IRP Site 7 and IRP Site 4 AOPCs IA and 2A (CH2N4 Hill, 2003a) were achieved. Therefore, the removal action at IRP Site 7 and Site 4 AOPCs IA and 2A is deemed complete by the DON. The DON will perform groundwater monitoring at IRP Site 7 for a limited time to confirm that the groundwater is not impacted. In addition, the DON will implement periodic landfill cover inspection and maintenance following the closure of IRP Site 7 04105GDI PmICbseoutRp!_ Sues4 &7 ES -6 Draft Protect Closeout Repon NTCRA IRP Sae 7 and Sae 4 Na \al Weapons staum, Seal Beach DCN PWSD- RAC -04 2056 C70 Na D023 Revtsmn D, 061I S/04 Area I (landfill). A Post - Closure Inspection and Maintenance Plan will be prepared, which will _ .: describe in detail the landfill -cover inspection and maimen�nce activities, procedure and schedule. The Post - Closure Inspection and Maintenance Plan will be prepared by the DON and implemented upon its approval by the regulatory agencies. 04 20 i 6 D-P rot C loseoufti Siles4 &7 ES-7 Dmfr Project Closeout Report NTCRA IRP Sae 7 and Site 4 Naval Weapons Station Seal Beach - DCN FWSD- RAC - 04-2056 CTO No 0023, Revision 0, 06118/04 TABLE OF CONTENTS PAGE EXECUTIVESUMMARY ............................................................................ ...........................ES -1 LISTOF TABLES ............................................................................................. .............................iv LISTOF FIGURES .................................. . ...................................................................................... v ABBREVIATIONS AND ACRONYMS .......................................................... .............................vi 1.0 INTRODUCTION ............................................................................... ............................... 1 -1 1.1 PROJECT OBJECTIVE ............................................................ ............................... 1 -1 1.2 REPORT ORGANIZATION ....................................................... ............................1 -2 2.0 SITE CONDITIONS ........................................................................... ............................... 2 -1 2.1 FACILITY LOCATION AND BACKGROUND .................... ............................... 2 -1 2. 1.1 IRP Site 7 ................................................................... ............................... 2 -1 2.1.2 IRP Site 4 AOPCs I and 2A .................................... ............................... 2 -2 2.2 GEOLOGIC SETTING ............................................................. ............................... 2 -2 2.3 WASTE AND CHEMICAL CHARACTERISTICS - IRP SITE 7 ......................... 2 -3 2.3.1 Chemicals of Potential Concern — IRP Site 7 ............ ............................... 2 -4 2.3.2 Nature and Extent of Contamination — IRP Site 7 ............................... :.... 2 -5 2.4 CHEMICAL CHARACTERISTICS - IRP SITE 4 AOPCS IA AND 2.A .............. 2 -6 2.4.1 Chemicals of Potential Concern — IRP Site 4 AOPCs 1 A and 2A............ 2 -6 2.4.2 Nature and Extent of Contamination — IRP Site 4 AOPCs 1 A and 2A .... 2 -7 2.5 RISK EVALUATION — IRP SITE 7 ........................................ ............................... 2 -7 2.6 RISK EVALUATION — IRP SITE 4 AOPCS IA AND 2A ..... ............................... 2 -8 3.0 REMOVAL ACTION OBJECTIVES AND CLEANUP GOALS ..... ............................... 3 -1 3.1 SIGNIFICANT APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS.................................................................... ............................... 3 -1 3.1.1 IRP Site 7 ................................................................... ............................... 3 1 3.1? IRP Site 4 AOPCs I A and 2A .................................... ............................... 3 -2 3.2 OBJECTIVES OF THE REMOVAL ACTION AND SOIL TARGET CLEANUPGOALS .................................................................. ............................... 3 -2 3.3 SELECTED REMEDIAL TECHNOLOGY .............................. ............................... 3.3.] IRP Site 7 ................................................................... ............................... 3-4 3.3.2 IRP Site 4 AOPCs I A and 2A .................................... ............................... 3 -4 4.0 FIELD ACTIVITIES ......................................................... . .................................. - ............ 4 -1 4.1 SUBCONTRACTING/ PROCUREMENT ................................... ............................4 -2 4.2 NOTIFICATIONS .................................................................... ............................... 4 -3 4.3 PREPARATORY ACTIVITIES AND MOBILIZATION ....... ............................... 4 -3 6:7056DrProlC1oseomRpt Sites4R7 1 Drag Protect Closeom Repon NTCRA IRP Site 7 end Site 4 Naval Weapons Station Seal Beech DCN FRN'SD-RAC -042096 CTO No 0073. Revision 0, D611 S/(4 TABLE OF CONTENTS m -- — (Continued) PAGE 4.4 GEOPHYSICAL SURVEY ...................................................... ............................... 4 -4 4.5 LAND SURVEYING ................................................................ ............................... 4 -4 4.5.1 IRP Site 7 ................................................................... ............................... 4 -4 4.5.2 IRP Site 4 AOPCs I A and 2A .................................... ............................... 4 -5 4.6 REMEDIATION /REMOVAL ACTIVITIES ........................... ............................... 4 -5 4.6.1 IRP Site 7 .Brea 1 ........................................................ ............................... 4 -5 4.6.2 IRP Site 7 Area 2 ................:....................................... ............................... 4 -8 4.6.3 IRP Site 7 Areas 3, 4, and 6 — Surface Debris Cl earing ............................ 4 -8 4.6.4 IRP Site 7 Area 5 — Removal of Buried Debris ....... ............................... 4 -10 4.6.5 UXO Screening ........................................................ ............................... 4 -12 4.6.6 IRP Site 4 AOPCs 1 A and 2A .................................. ............................... 4 -13 4.7 SOIL STOCKPILING, SAMPLING, AND ANALYSIS ....... ............................... 4 -16 4.7.1 Stockpile Sampling Methods and Procedures .......... ............................... 4 -17 4.7.2 Stockpile Sample Analysis and Results ................... ............................... 4 -17 4.8 FIELD SAMPLING METHODS AND PROCEDURES ........... ...........................4 -17 4.8.1 Sample Containers and Preservation ........................ ............................... 4 -17 4.8.2 Sample Packaging and Shipment ............................. ............................... 4 -18 4.8.3 Sample Documentation ................................................ ...........................4 -18 4.9 \'WASTE CLASSIFICATION AND DISPOSAL .................... ............................... 4-IS 4.9.1 Contaminated Soil Disposal .................................... ............................... 4 -18 4.9.2 Non- hazardous Soil /Debris Disposal ....................... ............................... 4 -19 4.9.3 Used Personal Protection Equipment ....................... ............................... 4 -19 4.10 SITE RESTORATION ............................................................ ............................... 4-19 4.11 DEMOBILIZATION .............................................................. ............................... 4 -21 4.1 1.1 Equipment Decontamination .................................... ............................... 4 -21 4.12 PHOTOGRAPHIC LOG ......................................................... ............................... 4 -21 4.13 PROJECT MANAGEMENT ...................................................... ...........................4 -21 5.0 COSTS OF THE REMOVAL ACTION ............................................. ............................... 5 -1 6.0 PUBLIC INFORMATION /COMMUNITY RELATIONS ACTIVITIES ......................... 6 -1 6.1 PUBLIC IN FORMATION ........................................................ ............................... 6 -1 6.2 PUBLIC PARTICIPATION ..................................................... ............................... 6 -1 7.0 EFFECTIVENESS OF THE REMOVAL ACTION ........................... ............................... 7 -1 7.1 CONFIRMATION OF LANDFILL COVER PLACEMENT AND REMOVAL OF SURFICIAL AND BURIED NN7ASTE AT IRP SITE 7 ................ 7 -1 7.2 CONFIRMATION SAMPLING RESULTS FOR IRP SITE 4 AOPCS IA AND 2A AND SUMMARY OF RESIDUAL RISK ................ ............................... 7 -3 N2056D. NaICl *s o.fti Sitcs4 &7 11 Draft Prolecl Closeom Report NTCRA IRP Snc 7 and Srie 4 Naval Weapons Sutmn Seal Beach DCN_ FWSD- R.4C -0- -2056 CTO No OOH, Rm,,sion 0, 06x1 S/04 TABLE OF CONTENTS -- - (Continued) - - -VIES$ PAGE 8.0 SUMMARY AMID RECOMMENDATIONS .....................................: ............................... 8-1 9.0 REFERENCES .................................................................................... ............................... 9-1 APPENDICES Appendix A Appendix B Appendix C Appendix D Geotechnical Laboratory Test Reports Ordnance Certification- and Verification Logs Chain -of- Custody, Laboratory Analytical Reports, and Data Validation Summary Reports Photographic Log of the Removal Activities 0 +2056DrPrujCloseouIRpl_SLLes4&7 111 Drafl Prolett Closnui Repo" NTCRA IRP Sne 7 end Sue G Nara) U'eayons Saoon Seal Reach DCN FWSD- R -4C -04-2056 CTO No 0023, Rems,on 0, 06 /1 A /04 LIST OF TABLES Table 4 -1 Summary of Analytical Results from Soil Obtained from the Station Wharf Table 4 -2 Summary of Analytical Results for IRP Site 5 Stockpile Soil, Imported Fill; and Imported Topsoil Table 4 -3 Summary of Lead Concentrations in Soil — Based on Pre - Excavation Sampling Results for IRP Site 4 AOPCs 1 A and 2A Table 4 -4 Summary of Analytical Results from the Confirmation Samples — IRP Site 4 AOPCs I A and 2A Table 4 -5 Summary of Analytical Results for the Stockpile Samples — IRP Site 7 Area 5 and IRP Site 4 AOPCs I and 2A 04056DrProlCloseoutRpt Srtes4S7 Iv Dmft Prnlect Closenul Report 14TCRA IY,P Sac , and Sne 4 Naval Weapons Station Seal Beach DCN PWSD- RAC - 044056 CTO No 0023 Revision 0, 06/16/04 LIST OF FIGURES Figure 1 -1 Regional Location Map Figure 1 -2 Site Vicinity Map Figure 1 -3 Site Plan - IRP Site 7 Figure 2 -1 Lead Concentrations in Soil - Based on Pre - Excavation Sampling Results for IRP Site 4 AOPC IA Figure 2 -2 Lead Concentrations in Soil - Based on Pre - Excavation Sampling Results for IRP Site 4 AOPC 2A Figure 4 -1 Landfill Cover Repair Grading Plan for Site 7 Area 1 (Landfill) and Backfill Compaction Test Results Figure 4 -2 As -Built Topographic Map of IRP Site 7 Area I Fiwre 4 -3 Geophysical Survey Results for IRP Site 7 Areas 3 and 4 Figure 4 -4 Geophysical Survey Results for IRP Site 7 Area 5 (Eastern and Western Trenches) Figure 4 -5 Final As -Built Grades and Topographic Survey of IRP Site 7 Area 5 Figure 4 -6 Lead Concentrations in Soil Based on Post - Excavation Confirmation Sampling Results for IRP Site 4 AOPC 1A Figure 4 -7 Lead Concentrations in Soil Based on Post - Excavation Confirmation Sampling Results for IRP Site 4 AOPC 2A Figure 4 -8 Final As -Built Elevations of Site 4 AOPCs I A and 2A and Backfill Compaction Test Results Figure 4 -9 ReveRetation Areas 1142056Dd'mlClocenmRpt SRes4d7 V D,oh I'mlen Closeout RePnrt N7CR4 IRP Site 7 and Sre 4 Naval Weapons Season Seal Beach DCN FWSD- RAC -04 -7056 C70 No 0023, Revisor 0, 06/1 @104 APPENDIX D PHOTOGRAPHIC LOG OF THE REMOVAL ACTIVITIES 047056DrProlCloseoutRpt S,te54R7 Diatt hq n Closeout Repon NTC'RA IRP Srte 7 and Site 4 Nara) Weapons Station Seal Bead, DCN PP'SD- RAC-04?056 CTO No 0033, Revision C, 0bil S /04 'T d w �n (`1 k O N rn T] N � N N f UJ � U N O � b v � N � N N % O N _ O O N � O F. [1i M O N O (Q U _O N N O G O ti N U O id N N V 0 O L c N V id N L N N Cfl 4- O CI N GII O 0. Y O 4 O t U I� U U a .1 U O rl 5 r� P U .. U. O U m u U .0 ro .. O N � N O ~ U N Q U .O N N 3 0 0 a 5 0 cL N v b N ^ J 'o R [O ^ O G U _= v � z 0 v o wti N O � U N n v N V b n m U 'p �+ N U G U r- 2 � _O f. O a a 0 r a rl k O v LI) Q. G U W ro O Cn ti ti -- N ? p 2 O N cA -0 N 4 y O 4 i y A v. v w O O .D v N r- b � N 'O N � O U N O v 3 r _o 0. b to rn fl N C W U N O (i N � rl i Q N ,y c N V �O N N U u U O i 0 C- 1i w 0 a v �Il A 4 i s G F U _ram. Photo 9. An excavator was used to excavate the lead- contaminated hot spots at AOPCs 1 A and 2A. Photo 10. A 50 -foot by 50 -foot excavated grid cell is shown here. Most grid cells were excavated to a depth of 1 foot bgs CP] 7:;frl I loi Appendix D Photos Page 5 of 2; N V ti U U N W G N N V. oD A C b 'y O O O � A N F r o � 4^ 1 'G i0 v u G � kD v o. F c1 O U1 .r O s a N O U :J O ES F G W b U N U N 3 0. m c U C rn rl 0 O N JO d 0. f 0 r U Photo 13. Following initial confirmation sampling, grid cell floors or sidewalls with lead contamination exceeding TCGs were further excavated. '�...*,�,. a .F'� -rte. �•+c��_a�' _ � �_ , .a. Photo 14. Backfiill was placed in the excavated grids within AOPCs I A and 2A after satisfactory confirmation sampling results. Co 1;041165 r,pp =jai. n Ph tw Page 7 of 23 Photo 15. Excavated grid cells were cordoned with caution tape until the confirmation test results were received, allowing the cell to be backftlled. Photo 16. Only a few grid cells required excavation up to 2 feet bgs. cTO 23VA 1165 App"diz n Photos Page 8 of 23 Photo 17. Following confirmation sampling results which indicated that the TCG had been met, the excavated grid cells were backfilled and graded. Photo 18. Surface debris removed from Areas 3, 4, and 6 consisted mainly of rusted metal, wood, and plastics. cro +_; A1165 Appwdlx D mmw Page 9 of 23 Photo 19. A geophysical survey of Areas 3 and 4 was conducted following initial surface debris removal. Photo 20. An example of what was determined to be ordnance found in Areas 3 and 4 during surface debris clearing. CTO 23 \041165 Appendix D Photos Page 10 of 23 Photo 21. Buried debris in Area 5 was excavated to a minimum depth of 9.5 feet and until the native soil was encountered. Photo 22. The upper 3 to 4 feet of the soil in Area 5 was for the most part clean overburden soil. Buried debris was encountered beneath the clean overburden soil. CTO 2M41165 Appendix D PUwm Page l 1 of 23 Photo 23. The eastern trench at Area 5 was excavated in 40- foot -long sections. The clean overburden soil was excavated and placed to the side and reused. Photo 24. Waste over Area 5 side slope and brackish water seeping from several seeps in the side slopes adjacent to the trenches. CTO'_z \ba 1165 Aprend, D Phoms Page 122 of 23 Photo 25. Following the excavation and back511 of the trenches, the excavator was used 10 remove dte debris along the eastern slope of the Perimeter Pond. Photo 26. Clean fill was placed over the excavated eastern slope of the Perimeter Pond, and the slope was graded with a 4H:1 V inclination. Cro 23W41165 nppeMix n nroI. Page 11 of 23 Photo 27. UXO Technicians screened the debris excavated from Area 5. Photo 28. A portion of stockpiled debris excavated from Area 5 trenches awaiting LTXO screening. CTO 23TA 1165 Appeadia D Photas Page 14 of 23 Photo 29. Duinim ordnance scrap found during screening of material removed from Area 7. Photo 30. Ordnance scrap discovered and removed during screening of the buried waste excavated from Area 5. C 03VAI165 Appwdix D Pw os Page 15 of,, Photo 31. Ordnance scrap metal was removed from the Area 5 excavated buried waste during UXO screening. m fie^ x i 3> �. MZ, 54 ib . C3�` Photo 32. Scrap ordnance- related items, including ordnance containers made of plastic were removed. cro 11WA 1165 APr�,a . o Phocm Page 16 of 23 Photo 33. A 12- feet -x+ide V -ditch was constructed connecting the Perimeter Pond and die East Pond. Photo 34. A horse- shoe - shaped V -ditch with a 12 -foot wide cross section was constricted in Area 5. CT0 23VM 1165 Append;, D Ph.,. Page 17 of 23 Photo 35. Picture of the horse- shoe - shaped V -ditch looking north. Photo 36. Soil cover was placed over the lauidfill in 6- inch -thick compacted lifts. CTO 2VVW 1 165 Appmdis D Photos Page IS of 23 Photo 37. Prior to placement of soil for landfill cover repair, the sub -grade was compacted with a sheep -foot compactor. Photo 38. Dredged sediment material imported from the Station Wharf was used as cover repair soil. The material was placed in 6 -inch compacted lifts. cr023XMI t6> nppw& o anon. Page 19 of 23 Photo 39. The soil cover v� as compacted to minimum of 90 percent compaction. Photo 40. A blend of seed mix composed of seeds from native vegetation species was used for revegetating the landfill cover and the AOPC 2A disturbed areas. CTO 23 \W t 165 Append;, n Phaos Page 20 of 23 Photo 41. Contaminated stockpiled soil was covered with 10 -mil PVC liner. Sandbags were placed over the liner to prevent it from being blown away Photo 42. The stockpile was subdivided into approximately 100 -cubic yard segments. Composite samples were collected from each segment for waste classification. CTO li\041165 Appmdiv D Phul. . Page 21 of 23 Photo 43. An excavator was used for loading the contaminated waste and debris in end -dumps for off -site transportation and disposal. Photo 44. All end dmnp trucks were weighed after being loaded and before leaving the site. CTO 23 \041165 Appendix D Phms Page 22 of 23 Photo 4f�. All end dump trucks were covered after being loaded and weighed, and before leaving the site. Photo 46. The stockpile area at the Station Wharf was re- graded and silt fencine was installed to minimize erosion and runoff. cro 23tU4 t t66 Ap,a , n Photo. Page 23 of 23