The one acre Birch Swamp Road Site (the Site) is located in Warren, Rhode Island, off of an unnamed, unpaved access road that runs east-to-west, intersecting Birch Swamp Road to the west.
EPA conducted environmental investigations at the Site in July 2007, April and August 2008. Sampling results indicated elevated levels of heavy metals (including lead) and polychlorinated biphenyls (PCBs) to be present in surface soils at the Site, exceeding the Rhode Island Department of Environmental Management’s (RIDEM) most stringent residential cleanup criteria. For additional information on the Site background please refer to “POLREP #1 – Initiation of Action.”
The current EPA cleanup is addressing the lead- and PCB-contaminated surface soils on the property.
Excavation work began during the first week of September, with contaminated soils being stockpiled in a staging area located within the foundation footprint.
The contaminated area has been divided into 22 square or rectangular grids. Each grid is excavated down to 6 inches below ground surface (bgs) and subsequently sampled along the floor and perimeter sidewalls. Additional rounds of 6 inch excavations and sampling are performed if sample results do not meet the cleanup criteria, up to a maximum of 3 feet bgs.
To date, 5 of the 22 grids have been completed, achieving the site cleanup criteria. These grids were excavated to depths ranging from 6 inches to 2 feet bgs.
The Warren Department of Public Works (DPW) is sharing their water source with EPA for the cleanup. EPA’s water truck refills daily at the DPW and is used to keep all road and soil surfaces moist and from dust. The effectiveness of the dust controls is being verified by air monitoring. To date, no exceedences of any site air quality criteria have occurred.
Once excavation work is completed, the following activities will be undertaken as part of the cleanup action:
- Test pitting in areas suspected to contain buried metal debris (e.g., drums) that may be causing or contributing to the soil contamination;
- Backfilling of excavations with clean fill materials;
- Removal of contaminated materials for off-site disposal at EPA-approved disposal facilities; and
- Repairs to areas disturbed by site activities, for example, by applying topsoil, re-seeding, and plantings.
The funding ceiling for the Superfund Technical Assessment and Response Team (START) contractor was increased from the project’s contingency fund, from $27,000 to $99,699. This additional funding was necessary to cover costs associated with the magnetometer survey work and soil sampling.
A magnetometer and “terrain conductivity” survey of the Site took place on August 18 and 19, 2008, resulting in the identification of several areas on the Site suspected to contain subsurface metal debris that might be causing or contributing to the surface soil contamination.
Test pitting was conducted on September 17, 2008 in one of the suspect areas, under the supervision of ordnance experts, who were retained as a precautionary measure based on information provided by a neighbor who had recalled that specific area being used as a sorting and possible disposal site for spent munitions. In exploring this area no ordnance material was found, however crews did uncover miscellaneous construction and demolition debris (scrap metal, metal piping and sheeting, asphalt, brick, concrete, etc.) and numerous tires (many still containing the steel rims), the metal in which is the likely source of the anomalies detected during the magnetometer survey.
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