The California Department of Toxic Substances Control (DTSC), pursuant to authority granted under Division 4.5, California Code of Regulations, Title 22, Chapter 14, is proposing a final remedial action for the Former Railroad Right-of-Way (Vanden Road) (Site). Based on the Phase II Environmental Site Assessment (ESA)/Preliminary Endangerment-Equivalent Report (PEA) prepared in March 2020 and revised in September 2020, arsenic was identified as the chemical of potential concern (COPCs) in soil at the Site, and as the primary chemical of concern (COC) for the Site. The COC is generally present within the upper 2 to 3 feet of soil at the Site, within the area where the former railroad line was located. The areas with impacted soil are confined to within 50 feet of the former railroad spur right-of-way (ROW) centerline (centerline exposure unit).
The Site is located within the former railroad ROW located on property owned by the City of Fairfield, along Vanden Road-Jepson Parkway, approximately 3,500 feet east-northeast of the Peabody Road/Vanden Road intersection to the southwest. It extends north-northwest from Vanden Road-Jepson Parkway roughly 2,300 feet to a point located 1,500 feet from Peabody Road to the southwest.
The remedial action will excavate contaminated soil from certain identified portions of the Site and bury/encapsulate the impacted soil in other portions of the Site under a minimum of three feet of clean, imported soil. The proposed remedial approach will involve the removal of soil from portions of the 50-foot-wide centerline exposure unit and placement of impacted material in the encapsulation zone of the Site. Approximately 6,500 cubic yards of contaminated soil will be excavated and encapsulated (buried) beneath portions of the proposed recreational trail. Soil excavation, handling, and stockpiling will be performed in a manner which limits and controls the mixing of contaminated soil with uncontaminated soil. This removal action will reduce the human health risks to levels that allows for the redevelopment of the Site for recreational purposes and be protective of future recreational users of the Site. Please refer to Attachment A.