NorCal Region BECOS TO 2 PWS Attch 2 - Base Specific Req Mather Dft 19 SEP 19 v3.0.docx

FA4890-06-R-9999

Attachment 1

APRIL XX, 2009

- final –

BECOS TO 2

ATTACHMENT 2

19 September 2019

1.1 Scope

The former Mather Air Force Base (AFB) is listed on the National Priorities List (NPL) and has a Federal Facility Agreement (FFA) in place. Records of Decision (RODs) have been signed for all but one Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) sites included in this task order, and Remedy in Place (RIP) has been achieved for those sites. Property transfer from the Air Force has been completed for all of the sites included in this PBR.

In 2017 a new soil vapor source area was discovered near Building 4260 within the Main Base/SAC Area (MBSA) groundwater plume. A soil vapor extraction (SVE) removal action was initiated in August 2018. The Building 4260 soil vapor source area was added to Site SD057 because of its potential to impact groundwater in the MBSA groundwater plume. Note that discontinuing SVE is a rigorous process and regulators have been hesitant to approve in the past.

The 23 sites (or portions of sites) included in this task order are being addressed following the CERCLA process or state corrective action program (non-CERCLA). Regulatory oversight is provided by the U.S. Environmental Protection Agency (EPA), California Department of Toxic Substances Control (DTSC) and Central Valley Regional Water Quality Control Board (Water Board). Remedies include landfill caps, groundwater pump and treat, and soil vapor extraction (SVE). Groundwater contamination has migrated off-site and the Air Force conducts sampling of off-base wells under various easements, licenses, and letters of permission. In addition, the Air Force samples off-base water supply wells (county and private water company wells) as well as operates wellhead treatment systems on these wells as required. All of the sites included in this task order must be included in the Five-Year Review. Annual reporting of compliance with institutional controls (ICs) is also required.

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

· Contractor is responsible for maintaining GAC systems to treat PFAS at SD057 and WP007, monitoring system influent and effluent in accordance with the GAC system O&M Plans, and conducting quarterly/annual monitoring of guard wells and off-base drinking water wells for PFAS.

Contractors are not responsible for the following:

· Preparation of easements or letters of permission required for off-base extraction and monitoring activities.

· Payment of fees associated with off-base easements.

1.3 Applicable Documents

Key Documents

1.4 Work Ramp-Up and Transition

Transition of Work

Complete Reporting Complete

1.5 Remedial System Components

· See Attachment 1 regarding remedial system components.

2.6.1 Meeting/Teleconference Support

· BCT meetings are currently held on a semi-annual basis. Meetings are typically one full day and are held at the former McClellan Air Force Base.

· Technical Working Group (TWG) meetings are held on an as needed basis to discuss issues with regulatory technical experts. Meetings are generally 2-4 hours and are held at the former McClellan Air Force Base.

2.6.2 Public Meetings and Hearings

· The Mather RAB has been adjourned and no RAB meetings are held.

· Stakeholder meetings or other publicly attended meetings are held on an as needed basis. Meetings are generally 2-4 hours and are held at the former McClellan Air Force Base or other Sacramento area venue.

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

· Easements and/or letters of permission are required for extraction and monitoring activities on the off-base properties. The Air Force will prepare the easements and letters of permission, track receipt of signed permission letters, and pay all required easement fees.

· The Contractor is responsible for renewing the sewer discharge permit every three years and for preparing monthly sewer discharge reports.

2.9 Contractor Documentation

· No base-specific requirements.

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

· No base-specific requirements.

6.14 Land Use Controls (LUC)

· The Contractor shall conduct annual inspections and reviews to confirm compliance with all CERCLA and non-CERCLA environmental restrictions associated with the sites. Where possible, the Contractor shall obtain and provide copies to the Air Force of annual reporting required by state covenants for applicable sites by respective property owners. Although there are State Land Use Covenants on some properties, the Air Force is continuing to do annual inspections and reporting to ensure environmental restrictive covenants are being enforced.

6.15 Five-Year Reviews

· The current PBR contractor will complete the fifth Mather 5-year review, due by 30 September 2020. The next five-year review will be due by 30 September 2025.