AOC C – Transformer Storage Pads

AOC C, located near Building 2042, consists of three uncovered, concrete pads used primarily for outdoor storage of discarded transformers. However, other discarded electrical materials, including batteries were observed. During the 1993 inspection, three transformers were observed well outside of the concrete pads and sitting directly on bare soil. During the 1988 VSI and the 1993 follow-up inspections, oil staining inside the concrete pads and evidence of releases to soil were observed. A first phase RFI was mandated for this area in the RCRA permit.

Status

• RFI work plans were approved in 1995.
• Initial investigations, in accordance with the EPA approved RFI work plans, were completed along with the rest of the OU 1 work. Areas containing significant levels of PCBs were found immediately adjacent to the pads. Additional work was planned based on this finding.

  Before this work could be done, much of the surface soil was scraped and stockpiled on site. This was done by the BOS contractor when he mistakenly interpreted instructions to clean up the area before hurricane season to include soil and vegetation removal. This work negated the original sampling efforts since the soils sampled were largely removed.

  After extensive negotiations with the EPA and testing of the piles, the Navy was allowed to haul the stockpiled soil to the Station landfill. This was done only when each load passed field screening tests for PCBs.

• Re-characterization of the site soils was deemed necessary. Since releases of PCBs were established, sampling is not only required for surface soil but also for subsurface soils.
• A work plan for the re-characterization efforts was submitted and approved by EPA.
• Additional investigations were performed in September/October 1997.
• This unit is now being addressed with SWMU 46 because the two sites are similar. An outline for a streamlined CMS was submitted in December 1998.
• A streamlined CMS was submitted in May 1999. Following agency comments, a Final CMS was submitted in October 1999.
• A Revised Final CMS was submitted in January 2000 and approved in March 2000.
• The Draft CMI Work Plan Design Package was submitted in July 2000.
• The Revised final CMS Final Report was submitted in August 2000.
• Following agency comments, the Final CMI Work Plan Design Package was submitted in November 2000.
• The 100% Final CMI Work Plan Design Package was submitted in January 2001.
• EPA sent the CMI Work Plan out for public comment.
• The CMI was initiated in CY 2006.
• A Draft Project Closeout Report - Remedial Action for Soil Remediation was submitted to the EPA on December 4, 2009.