Thursday, June 16, 2016

Spring Valley Munitions Disposal Site Cleanup

During and after World War I, from 1917 to 1920, the U.S. Army conducted chemical warfare research, experiments and testing at its Washington, D.C. American University Experiment Station in an area now occupied by the Spring Valley neighborhood. Following WWI, some of the chemical agents, ordnance, and laboratory wastes generated at the site were disposed of at American University Experiment Station and in an adjacent area known as Spring Valley. Discovery of those buried munitions and chemical agents have resulted in both the Spring Valley neighborhood and the American University being designated a Formerly Used Defense Site (FUDS). If this site was not a military facility it would have been named a Comprehensive Environmental Response, Compensation, and Liability Act, or CERLCA site . This designation authorizes the U.S. Army Corps of Engineers (USACE) to address environmental contamination resulting from past Department of Defense activities at the American University/Spring Valley site using the CERCLA process. Though the U.S. Army Corps of Engineers, Baltimore District (USACE) has the lead responsibility for investigation and cleanup actions at the Spring Valley FUDS, they have entered into a formal partnering process with the U.S. Environmental Protection Agency (EPA) and the Washington, D.C. District Department of the Environment (DDOE).

Since 1993, the USACE has been investigating the Spring Valley Community to determine where and to what extent the Army disposed of buried ordnance, explosive wastes, and hazardous substances. USACE found several burial pits containing munitions and chemical agents as well as arsenic in soil exceeding background levels. The primary chemical agents found were mustard agent, lewisite, and their degradation products.

Army Corps of Engineers returned to the site in 1998 to further investigate potential ordnance burial pits on the residence of the Ambassador of South Korea. During this investigation, USACE discovered two burial pits containing munitions items and laboratory glassware, some of which contained traces of chemical agents. The Army Corps of Engineers has conducted an extensive soil investigation to determine the nature and extent of soil contamination within the site area. As part of this effort 1,632 residential, federal and District of Columbia, and commercial properties were sampled for arsenic, the main contaminant of concern in Spring Valley. Of the properties that were sampled, the Army Corps of Engineers identified 177 properties/lots that required remediation. The primary method of remediation was through excavation of the arsenic-contaminated soil.

In 1999, the EPA prepared a human health risk assessment for the site, conducting an analysis of soil sampling data collected between 1993 and 1995 at 16 locations throughout Spring Valley and American University site. The D.C. Department of Consumer and Regulatory Affairs and recommended site-wide comprehensive geophysical investigations, soil sampling, and a health study. In response to significant community and regulator concerns regarding possible soil contamination, the Army Corps of Engineers in consultation with the EPA Region 3 and the District of Columbia Department of the Environment (DDOE), developed a comprehensive plan to conduct arsenic soil sampling on every property within the SVFUDS and conduct additional geophysical investigations focusing on identifying additional potential burial pits as well as individual buried munition and explosives. In 2002, the Army Corps of Engineers determined that three artillery shells found at the Glenbrook Road burial pits contained arsine gas.

The Army Corps of Engineers also conducted an investigation to determine to what extent American University Experiment Station-related activities may have impacted the groundwater within the site. The investigation involves the installation of monitoring wells and the collection of samples from the wells and surface water locations. To date,the Army Corps of Engineers has installed 53 groundwater monitoring wells and sampled surface water at 25 locations. Perchlorate has been detected at levels above the EPA interim drinking water health advisory level of 15 parts per billion (ppb) at 2 locations in the project area. Arsenic has been detected in groundwater above the maximum contaminant level (MCL) for drinking water in one area. There are no known users of groundwater in the site. Though the Dalecarlia Reservoir is near the contaminated groundwater, any groundwater interchange is overwhelmed by the volume of water pulled daily from the Potomac. In addition, the drinking water is tested daily for perchlorate and arsenic.

The U.S. Army Corps of Engineers has released the final Feasibility Study report in accordance with the CERCLA or Superfund procedures. The purpose of the FS is to develop, screen, and provide a detailed analysis of remedial alternatives to mitigate: 1) unacceptable risks posed by soil contamination resulting from chemicals of concern (COCs), and 2) potential unacceptable explosive hazards due to munitions and explosives that may remain within the Spring Valley site. It is based on information, site characterization, and determination of potential risks or hazards to human health which is contained in the Site-Wide Remedial Investigation (RI) Report and Feasibility Study (FS). These are the final investigative reports in the CERCLA process.

The Feasibility Study has recently been released. The purpose of the Feasibility study is to develop, and provide a detailed analysis of remedial alternatives to mitigate: 1. unacceptable risks posed by soil contamination resulting from the chemicals of concern that remain in the soils of the area, and 2. potential unacceptable explosive hazards due to munitions and explosives that may remain within the site. It is based on information, site characterization, and a risk analysis determining the potential risks to human health and safety. The consultants examined the two identified areas of risk separately to make sure that both risks were fully addressed.

Based on the detailed analysis of contaminated soil remedial alternatives for the Spring Valley Site, the Feasibility Study recommends “Alternative 4,” which is Excavation and Off-site Disposal, as the most favorable remedial alternative to meet the soil remedial action goals of protecting human health and the environment at the most reasonable cost to the American people. Alternative 4 will meet the remedial action goals in the shortest time, with the fewest unknowns. It will address all chemicals of concern and it has been successfully conducted many times throughout the Spring Valley site.

Based on the analysis of the remaining explosive hazards the feasibility study recommends, Alternative 6, “Digital Geophysical Mapping of Accessible Areas and Remove Selected Anomalies,” as the most favorable remedial alternative to complete remediation. In both areas munitions and contaminated soil, the final selection of a preferred alternative will be formerly proposed and documented in the Proposed Remedial Action Plan.

The next step in the CERCLA process now that the Feasibility Study has been finalized will be for the Army Corps of Engineers to release the Draft Final Proposed Plan which is expected by the end of this week. The Proposed Plan formally presents the Army's preferred alternatives. A formal public comment period will be held to allow the community an opportunity to review and comment on the Proposed Plan before it is finalized. This is your opportunity to make sure that all your concerns are addressed. The best way to do this would be through the Restoration Advisory Board.

The Restoration Advisory Board is comprised of 13 Spring Valley community stakeholders as well as representatives from the Army Corps of Engineers, Environmental Protection Agency, the District Department of the Environment, as well as the nearby public school and American University. The RAB acts in an advisory capacity to assist the government agencies engaged in the investigation and cleanup of the Spring Valley site. The primary purpose of the Restoration Advisory Board is to involve the local community in the decision making process.

The next Restoration Advisory Board meeting is scheduled for Tuesday, July 12 at 7 pm. These meetings are open to the public. Currently, the Restoration Advisory Board (RAB) meets on the second Tuesday of every odd month for about 60-90 minutes in the ‘Undercroft’ meeting room at St. David’s Episcopal Church, 5150 Macomb Street NW, Washington, D.C.

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