Site Description
March 2004 Fact Sheet 2004-01
Demolition Area 2 is located on the northern portion of Camp Edwards, approximately 1.5 miles from the base's northern boundary with Sandwich. The 8-acre site was used from the late 1970s to the late 1980s as a demolition area. Records show explosive charges, including TNT and the compound explosive, C-4 (in quantities of less than 10 lbs.) were used at Demolition Area 2.
Demolition Area 2 consists of a clearing with a relatively shallow natural depression. The terrain is elevated to the north and east and densely vegetated outside of the clearing. A berm, comprised of a series of small soil piles is located just beyond the tree line on the western edge of the clearing.
Investigations to analyze contamination at Demolition Area 2 have included soil samples at approximately 40 locations and the installation of 8 groundwater-monitoring wells. The explosive chemicals RDX and HMX are the primary contaminants of concern at this site and have been detected in soil and groundwater. Perchlorate has not been detected in the soil or groundwater at Demolition Area 2.
This fact sheet describes a Rapid Response Action planned to address soil contamination at two locations on the Demolition Area 2 site.
Soil Rapid Response Action Work Plan
The Demolition Area 2 Soil Rapid Response Action Work Plan proposes the removal of contaminated soil that is a potential source of groundwater contamination. The areas where soil will be removed include a man-made berm and a 30-foot area at the center of the Demolition Area 2 site.
Berm Removal
Detectable concentrations of explosives chemicals including RDX, HMX and 2A- and 4A-DNTs have been found in soils collected from the "U"-shaped berm on the western edge of the Demolition Area 2 clearing. The presence of these chemicals is consistent with the types of explosives used in past Demolition Area 2 activities. The configuration of the soil berm, combined with the presence of explosive residue and metal debris (fence and wire) presumed to be from previous demolition activities, indicate that materials scraped from the surface of the demolition area during range maintenance activities created the berm.
The proposed Rapid Response Action calls for the excavation and removal of the berm. Although not all soil samples collected from the berm contained measurable amounts of explosives chemicals, the proposal calls for all of the berm to be removed since it is cost effective to do so.
30-Foot Area Removal
The explosives chemicals RDX, HMX and 2A- and 4A-DNTs also have been found in soils collected from a 30-foot area of soil located at the center of the Demolition Area 2 site in the vicinity of the groundwater monitoring well known as MW-16.
Treatment & Follow Up
The two proposed excavations at Demolition Area 2 would remove an estimated 825 tons of soil. This soil removal action is expected to reduce contamination that may be a continuing source of groundwater contamination. Following excavation, the proposal calls for the soil to be treated on-site, using the Thermal Desorption unit at Demolition Area 1, or disposed of at a licensed off-site location.
Post-excavation sampling will be conducted in order to document conditions after the cleanup.
Investigations at Demolition Area 2 will continue and the need for any additional cleanup activities will be evaluated during that process.
The Draft Demolition Area 2 Soil Berm Rapid Response Action Work Plan proposes the following activities:
- Excavation of 825 tons of soil to reduce/eliminate the source of groundwater contamination. Including:
- Removal of man-made berm to ground level
- Excavation of soil from 30-foot area at the center of site
- Use of Thermal Desorption unit at Demolition Area 1 to treat excavated soil on Camp Edwards or disposal of soil at licensed facility off-site.
Next Steps/Upcoming Activities
Next steps toward conducting the Rapid Response Action for soil at Demolition Area 2 include:
- Conduct a public comment period on the Draft Demolition Area 2 Soil Rapid Response Action Work Plan (3/23/04-4/6/04)
- Incorporate regulatory and public comments into the Rapid Response Action Plan (early spring 2004)
- Finalize the Rapid Response Action Plan (through spring 2004)
- Begin Rapid Response Action (summer 2004)
Opportunities for Public Comment
A 15-day public comment period will be held on the Draft Demolition Area 2 Soil Rapid Response Action Work Plan from March 23 - April 6, 2004. Visit the IAGWSP website to submit comments.
Details of the plan will be presented at the Impact Area Review Team Meeting on Tuesday, March 23, 2004, from 6 to 9 p.m. at the Holiday Inn - Cape Cod, 291 Jones Road in Falmouth.
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