EPA has been asked to investigate tetrachloroethylene (PERC) contamination in Hyattsville (Chillum), Maryland and Washington, District of Columbia. PERC contamination was discovered during an on-going investigation of a gasoline-products release from a service station located in Hyattsville near the Chillum PERC property. The site under investigation includes a dry cleaning facility and a residential community. The dry cleaning facility is located in Maryland and is immediately adjacent to the Washington, DC border. Groundwater flow flows from Maryland into Washington, DC, and one or more plumes of groundwater containing PERC may be present beneath the local residential community.
August 21-22, 2003: EPA, START, DC-DOH and local residents onsite. EPA and START contractors utilized a subcontractor to install and decommission permanent soil vapor implants. Two of the 13 permanent soil vapor implants installed in July 2003 were removed at the request of the respective residents. At both locations, the permanent implants were installed from outdoor locations. Subsequently, EPA and START contractors installed permanent implants through the concrete basement slab of the two residences using power hand-tools, and decommissioned the outdoor permanent implants at each location. The implants were installed no more than 5 feet below the basement slab level.
EPA and START contractors utilized a subcontractor to install five small-diameter driven monitoring wells. Six wells were installed in public areas during this phase of the project using a direct-push hydraulic device; one well was installed during the week of July 21, 2003. The wells were constructed of 0.75-inch polyvinyl chloride (PVC) and set with screened interval located across the water table observed in the associated soil boring. The wells were finished with flush-mounted, steel protective casings, and were designated WP-101, WP-102, WP-103, WP-104, WP-105, and WP-106.
EPA Community Involvement Coordinator Vance Evans met with a local citizens' committee that is actively involved in the site investigation. Key discussion focused on, first, listening to their concerns, then, enlightening them about the Superfund removal program and encouraging effective use of its community involvement process.
A. A START subcontractor will install and develop the five remaining proposed small-diameter, direct-push monitoring wells.
B. START contractors will collect groundwater samples from the six small-diameter wells and analyze the samples for volatile organic compounds.
C. START contractors will procure the services of a subcontractor to survey the monitoring wells in reference to a local fixed reference point of known elevation.
D. START contractors will procure the services of analytical services and collect active soil vapor samples from the two implants.
F. START contractors will procure the services of analytical services and collect two tap water samples from two homes in the community.
G. Attend public meetings and prepare presentations of completed, on-going, and planned activities in response to the PERC investigation.
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