EPA Offers Groundwater Remedies for Camp Edwards Site
A public comment period for a Remedy Selection Plan that outlines the proposed alternative for addressing groundwater contamination at the J-1 Range on the Massachusetts Military Reservation (MMR) will run through Aug. 17.
The plan outlines the alternatives presented in the J-1 Range Feasibility Study for addressing groundwater contamination at the site, along with the alternative recommended by the U.S. Environmental Protection Agency and the reasons for its selection. The plan proposes remedies for the J-1 Range northern plume, which contains RDX and perchlorate, and the J-1 Range southern plume, which contains RDX.
EPA will consider public comments and select a response action in consultation with the Massachusetts Department of Environmental Protection (MassDEP).
Monitoring and investigations have shown that there is no groundwater contamination from the site threatening public or private drinking water supplies. In addition, with information provided to date, EPA believes there are no active sources of contamination at the J-1 site. Surface contamination that could potentially migrate to groundwater has either already been removed or depleted. Alternatives in the Feasibility Study included No Further Action, Monitored Natural Attenuation and Land-use Controls, and several different Focused-Extraction scenarios.
The Remedy Selection Plan presents Focused-Extraction alternatives that would reduce site contaminants through both treatment and natural processes for both the northern and southern plumes.
For the northern plume, the proposed alternative consists of a new extraction and treatment system with two extraction wells, two mobile treatment units, and two infiltration trenches. The remedy is expected to reduce RDX to the Health Advisory level of 2 parts per billion (ppb) between 2031 and 2037 and to the excess cancer risk level of one in 1 million, which is currently 0.6 ppb, between 2047 and 2050. Perchlorate would be reduced to 2 ppb, which is the Massachusetts Maximum Contaminant Level, between 2035 and 2045.
For the southern plume, the proposed alternative consists of adding an off-base extraction well to the existing J-1 Range southern treatment system. The new extraction well would be in the vicinity of Little Acorn Lane in Forestdale. The system would use the existing on-base mobile treatment unit and two infiltration trenches. RDX is expected to decrease below 2 ppb by 2019 and below 0.6 ppb by 2024.
Both proposed alternatives would include groundwater monitoring to verify that the plumes are being reduced as expected and land-use controls to ensure there is no use of the contaminated water.
For both plumes, the extraction well locations will be determined by the most recent groundwater sampling data and the best balance between efficiency, cleanup time, cost, implementability, as well as environmental, public and worker impacts. The alternatives are expected to be permanent remedies because no further source-area contamination is likely at the site. The alternatives will comply with state and federal regulations and are protective of human health and the environment.
Information regarding the Remedy Selection Plan will be presented at a public meeting at 6 p.m., Aug. 2 at the Sandwich Town Offices at 16 Jan Sebastian Drive off Route 130 in Sandwich, Mass. Representatives from the Army’s Impact Area Groundwater Study Program (IAGWSP), EPA, and MassDEP will be available.
The Remedy Selection Plan as well as further information on how to comment are available on EPA’s website. The document is also available at the libraries in Bourne, Falmouth, and Sandwich.
Comments are to be submitted by mail to Jeanethe Falvey, US EPA, 5 Post Office Square, Suite 100 Mail Code ORA 20-1, Boston, MA 02109-3912, by fax to 617.918.0020 or by e-mail to falvey.jeanethe@epa.gov.
Responses to comments on the Remedy Selection Plan will be provided to the public with the J-1 Range Decision Document which will be finalized this summer.