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Overview of Pepco Benning Facility RI/FS
Overview of Pepco BenningFacility RI/FS
RI/FS Background
• Between 1985 and 2003, there have been six documented releases of PCBs into the environment at the facility. In each case, Pepco cleaned up the releases in accordance with applicable legal requirements.
• In September 2008, EPA conducted Site Inspection (SI) under CERCLA at Pepco Benning Facility. The SI revealed high levels of polychlorinated biphenyls (PCB) on‐site and in sediments near the facility.
• In December 2011, DDOE negotiated a Consent Decree with Pepco to conduct a Remedial Investigation and Feasibility Study (RI/FS) of the Pepco Benning facility and the adjacent portion of the Anacostia River.
Historical PCB Releases/ Cleanup Areas
1995
2009
1991
19881985
1997
Suspected Location of PCB Entry into the River. Based On 2009 EPA Site Inspection Report
Target Investigation Areas
RI/FS Objective• Characterize environmental conditions at Pepco Benningfacility.
• Investigate whether and to what extent past or current conditions at the site have caused or contributed to contamination of the River.
• Assess current and potential risk to human health and the environment posed by conditions within the study area (landside and waterside).
• Develop and evaluate cleanup options.
Waterside Investigation Area
Landside Investigation: Landside Study Area
Current Status: Landside Investigation
To date, Pepco has completed the following field investigative activities:• Surface soil sampling at twenty‐five (25) locations;• Storm drain sampling;• Five (5) Geotechnical soil borings• Thirty‐seven (37) DPT borings to collect soil and groundwater• DDOE and Pepco are working
to finalize the RI Addendum for installation of Monitoring wells
Waterside Investigation
• The power plant was built in 1906 and provided electricity supply to District of Columbia and nearby Maryland suburbs.
• In 1976 Pepco stopped burning coal at the Benning power plant.
• In June 2012, the Benning Power Plan was shut down. Pepco is currently dismantling the Power Plant buildings and associated equipments.
• Pepco expects to complete the power plant demolition by Fall 2014.
Current Status: Waterside Investigation
• Bathymetric and Utility Survey for the study area
• 20 surface water samples immediately above sediment‐water interface
• 55 surface sediment samples
• 55 subsurface sediment sample locations with depth up to 10 feet
Schedule as per Consent Decree
• Pepco Submission of Draft RI Report – Not more than 120 days after completion of RI field work
• Pepco submission of Draft FS Report – Not more than 180 days after completion of RI Field work or 120 days after approval of treatability study report, if required
• DDOE issuance of Record of Decision Regarding Cleanup Actions – Promptly after approval of RI/FS Reports
CSX Transportation Benning Yard
• On February 1, 2011, DDOE and CSX Transportation signed a consent decree that requires CSXT to conduct a site‐wide investigation and natural resource damage assessment; and clean up pollutants on or emanating from its Benning Road rail yard.
• To date, CSXT has completed landside investigation for the Yard office which was used to store and dispense diesel fuel to locomotives. The corrective action plan (CAP) for cleaning up spill‐contaminated soil and groundwater was approved by DDOE in April 2013.
• Field work associated with the CAP is expected to start in late summer 2014.
CSX Transportation Benning Yard
• A sediment investigation in Anacostia River and Fort DupontCreek was conducted in 2011.
• Currently, DDOE and CSXT are working together to update the site conceptual model and conduct hydrodynamic fate and transport model of the release from Benning Yard.
Washington Navy Yard (WNY) Operable Unit 2 Remedial Investigation
District Department of the Environment
March 2014
• The Federal Facility Agreement (FFA) between the Navy Yard, District of Columbia, and EPA was signed on June 30, 1999.
• The Districts role is a partnership with the Navy and EPA; however only EPA and the Navy have the authority to select a remedy.
• In 1999, the Near‐shore Sediment RCRA Facility Investigation (RFI) included the collection of surface sediment samples from 26 locations near the GSA property.
• The remedial investigation for the landside groundwater investigation (Operable Unit 1) {OU1} is ongoing and the results will be reported to EPA and DDOE in the coming weeks.
• The remedial investigation activities of the near‐shore sediments (Operating Unit 2) {OU2} were conducted in the year 2010 in accordance with the FFA.
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Washington Navy Yard (WNY)‐ Brief Background
• For the 2009 sampling phase documented in the 2011 RI Report, The Washington Navy Yard investigation included the collection of 20 samples to:– help characterize the surface sediments in and around Operable Unit 2 (OU2), – to fill existing data gaps, to characterize the sediments near the Navy and D.C.‐
owned outfall locations, and – to complement existing surface sediment results for the previous surface
sediment investigation • OU2 includes the entire 2,400 foot site waterfront and extends the length
of the facility’s piers (approximately 200 feet) into the Anacostia River. • Subsurface sediment sampling was conducted at 34 locations within and
near the pier area to depths ranging from 10 to 12 feet (middle depth) to approximately 20 feet (deep depth) below the river bottom.
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WNY – Remedial Investigation‐ Sediments
• For surface sediment, the highest constituent concentrations are consistently found at the western end of OU2, in the area of former Pier 5 and D.C. Combined Sewer Outfall 14, D.C. Storm Sewer 01, and Washington Navy Yard Outfall 9.
• Higher constituent concentrations are also found near some of the other Navy Yard outfalls, and at mid to deeper level depths.
• The 2011 RI report indicates that comparisons of constituent concentrations at individual locations sampled in both 1999 and 2009 were inconclusive; concentrations of PAHs and PCBs were generally more variable than concentrations of metals.
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WNY – Sediments Continued
• The Navy is currently in the preliminary stages of developing a Feasibility Study (FS) sampling plan to address data gaps in the nature and extent of the contamination in the near shore sediments.
• On March 4, 2014, Navy presented a Strawman (Draft) FS Sampling and Analysis Plan (SAP) to DDOE and EPA.
• A meeting is scheduled for March 19, 2014 to discuss EPA and DDOE’s comments to the Strawman (sampling locations/depths, etc.) and to get consensus on the Navy’s approach.
• The Draft Remedial Investigation Report for OU2 is under review and comment by DDOE, EPA, and Navy.
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Current Status
