TO 2 PWS Attch 2 McClellan Base Spec Req NorCal BECOS vf4.docx

FA4890-06-R-9999

Attachment 1

APRIL XX, 2009

- final –

FA8903-20-R-0014 TO 2

ATTACHMENT 2

norcal region - mcclellan 5 December 2019

1.1 Scope

The former McClellan Air Force Base (AFB) (McClellan or Base) was an active industrial facility since its dedication in 1939, when it was called the Sacramento Air Depot. Operations changed from the maintenance of bombers during World War II and the Korean conflict to the maintenance, repair, modification, and disassembly of jet aircraft in the 1960s. In the 1980s and 1990s, operations were expanded to include the maintenance and repair of communications equipment and electronics. Hazardous substances were utilized at a number of facilities on-base, including disposal pits, washracks, fuel and oil storage, electronics repair and testing facilities, aircraft painting facilities, wastewater treatment plants, machine shops, and open storage areas. In 1995, the Congressional Base Realignment and Closure (BRAC) Commission recommended closure of McClellan; and on July 13, 2001, McClellan was closed as an active military facility.

In response to detections of contaminants in soil and groundwater, McClellan initiated the first phase of the IRP in 1981. Under the IRP, the investigation and remediation of contamination at the Base has been conducted in accordance with CERCLA as amended by SARA and the NCP. On October 15, 1984, EPA proposed listing McClellan as a candidate site for inclusion on the NPL. McClellan was formally placed on the NPL on July 22, 1987. In 1989, the Air Force, EPA Region 9, and the California Department of Health Services (CDHS) signed an Interagency Agreement for the cleanup. The Interagency Agreement was executed in 1990. CDHS was later reorganized, and DTSC assumed CDHS’s responsibilities under the Interagency Agreement.

The Basewide Volatile Organic Compound (VOC) Groundwater Record of Decision (ROD) (CH2MHill 2007) presents the Selected Remedy for VOCs in groundwater at McClellan in Sacramento, California. This ROD addresses remedial actions for VOC contamination in the Groundwater Operable Unit (GWOU), including all portions of the VOC groundwater contaminant plumes above the cleanup levels, regardless of whether they are located within or outside the former base boundaries. Trichloroethene (TCE) is the predominant contaminant of concern (COC) in groundwater but there are 12 other VOCs with reported concentrations above maximum contaminant levels (MCLs) that are addressed in this document. This ROD also addresses VOC contamination in the vadose zone that threatens to migrate to groundwater. This ROD is supported by the 1999 Basewide VOC Feasibility Study (FS) (CH2M HILL, 1999) and the 2004 Addendum to the Basewide VOC FS (AFRPA, 2004c).

The ROD established 5 parts per billion (ppb) as the cleanup standard for TCE. The Air Force (AF) will proceed with cleanup until such time as 5 ppb is achieved in each plume, as defined by the BRAC cleanup team. At that point, the AF, in collaboration with the State and EPA Remedial Project Managers, will complete an analysis and prepare a report (using agreed upon models) which evaluate the technical and economic feasibility of continuing remediation until plume levels reach 2.3 ppb TCE.

While TCE is the primary COC, the selected remedy requires cleanup of all COCs to their respective MCLs. The Selected Remedy also includes institutional controls to prevent human exposure to VOCs at concentrations above MCLs and to protect the integrity of the remedial systems and associated monitoring systems. For groundwater plumes that are on-base, the AF is responsible for implementing, maintaining, enforcing, reporting, and monitoring the institutional controls, before and after property transfer until the remedial action is complete and institutional controls are no longer necessary. For groundwater plumes that are off-base, Sacramento County has implemented a consultation zone by ordinance to review any new well installations, and west of the base Sacramento County and the City of Sacramento have implemented a prohibition area to prohibit well installations.

The remedy includes groundwater extraction and treatment combined with in situ SVE. Under the Selected Remedy, the existing groundwater extraction and treatment system, which started operation in 1987 and was subsequently expanded, will be used to clean up groundwater. As part of the selected remedy, treated groundwater is discharged to surface water (Magpie Creek). SVE systems have been used since the 1990s to remove VOCs from the vadose zone that threaten to migrate to groundwater. To-date, 14 SVE systems have been installed at McClellan. All but two of these systems have been decommissioned. The two remaining systems, IC-37 and OU C1, are undergoing rebound analysis under the SVE Termination and Optimization Process (STOP) evaluation. It is anticipated that these remaining systems will be closed by end of the current PBR contract in September 2020.

In September 2009, the AF completed the Non-VOC Amendment to the VOC Groundwater ROD to establish the remedy for 1,4,-dioxane, total and hexavalent chromium, and perchlorate.

In June 2016, the AF and EPA signed an Explanation of Significant Difference (ESD) to the VOC Groundwater ROD revising the cleanup level for hexavalent chromium (Cr6) from 50 ug/l to 14 ug/l, which equates to the naturally occurring background levels for Cr6 at McClellan.

In addition to the requirements presented in this PWS, this scope includes the following:

· No additional base-specific inclusions.

Contractors are not responsible for the following:

· Receipt and placement of accepted waste in the Consolidation Unit (CU) (LF010) along with opening and winterization due to the uncertainty associated with the frequency and quantity of accepted waste. Only CU O&M is included in this TO.

· Investigation and remediation of PFAS, except as noted in Attachment 1

· Payment for easements.

1.3 Applicable Documents

Key Documents

1.4 Work Ramp-Up and Transition

Transition of Work

Complete Reporting Complete

2.6.1 Meeting/Teleconference Support

· BCT meetings are currently held monthly with State and Federal regulators in attendance (McClellan Business Park (MBP) 2nd floor conf. room at McClellan), these are typically 3-hour meetings

· Technical Working Group (TWG) meetings are currently held quarterly with regulators at the McClellan AFCEC office to discuss the Quarterly GW and SVE Report (AFCEC office at McClellan), these are typically 3-hour meetings

· Comment resolution meetings (AFCEC office at McClellan) are currently held quarterly, these are typically two-hour meetings.

· Current bi-weekly meeting with AF RPM to discuss GW and CU activities (AFCEC office at McClellan).

2.6.2 Public Meetings and Hearings

· RAB meetings are currently held twice a year. The Contractor may be asked to provide support in preparing briefings to the public. Meeting length is typically two hours.

2.6.5 Site Access: Permits, Easements, and Work Site Access

· The AF has a waste discharge permit issued by the CVRWQCB that regulates discharges of treated groundwater to surface water (Magpie Creek) from the GWTP. The Contractor shall perform monthly sampling of the GWTP effluent to ensure compliance.

· The AF has a sewer discharge permit that regulates sewer outfall discharges from the CERCLA wastewater treatment plant. The Contractor shall report flow meter readings each month and provide analytical results for discharges from the CERCLA wastewater treatment plant

· The AF has a stormwater discharge permit associated with stormwater and leachate coming from the operations of the CU.

· The AF has a number of off-base property easements that allow access to monitoring wells located on private property. As needed, expiring easements are renewed to allow continued access to the wells. No easements are due to expire during this TO.

· The AF has radiological materials storage and handling permits issued by the AF Radioisotope Committee (RIC) that support ongoing radiological cleanup and the ongoing operation of the CU. The permits have specific conditions that must be complied with.

3.4 Computer Aided Design Drawing (CADD) and Geographic Information Systems (GIS) Updates

· No base-specific requirements in addition to those in the PWS.

6.14 Land Use Controls (LUC)

· Annual LUC compliance inspection and reporting is performed by AF personnel on the sites under AF control. The privatized sites are inspected and reported upon by EPA, its contractors, and McClellan Business Park. The contractor is not required to perform annual LUC inspections.

6.15 Five-Year Reviews

· The AF completed the 2019 Five Year Review document in Sep 2019. The next document will be due in Sep 2024. The document is a joint effort, with the AF handling sites under AF lead (approximately 30 sites) (Part A of the Five-Year Review Report), and the EPA handling privatized sites under EPA lead (200+ sites) (Part B of the Five-Year Review). Statutory and policy reviews are combined. Under this task, the contractor completes Part A and EPA completes Part B. Once each part is finalized and signed, the contractor issues the final version of both parts in one binder. This TO also includes preparation of the 2029 Five Year Review.