BOSTON, SEPTEMBER 21, 2016 -- The U.S. Environmental Protection Agency (EPA) amended its cleanup decision for a portion of the Savage Municipal Water Supply Well Superfund Site. This new cleanup plan will encompass contaminated groundwater, cleanup groundwater and ensure public health protections on the site. Construction for the amended remedy will take approximately one year once it is started, and will cost about $10,800,000.
This updated cleanup is outlined in a document called an Amended Record of Decision for Operable Unit 1 (OU1). The original cleanup plan called for cleaning groundwater at the site. Within certain areas of the overburden and bedrock this has proven to be technically impracticable from an engineering perspective. The new cleanup plan makes adjustments to this portion of the cleanup by treating and containing the most highly contaminated groundwater in the overburden and bedrock aquifers within OU1.
There are other aspects to the cleanup amendment at the Savage Municipal Water Supply Well Superfund Site that will help achieve a cleanup to benefit the community and ensure protections to public health and the environment. In the areas of the site where it is not technically impracticable, contaminated groundwater will go through a process called monitored natural attenuation (MNA) to achieve beneficial reuse standards and to prevent exposure to contaminated groundwater until the cleanup standards are achieved. Institutional controls (ICs) at the site will prevent exposure to contaminated groundwater and to protect the components of the remedy.
Historically, the Savage Municipal Well provided potable drinking water to approximately 10,000 residents in the Town of Milford. In February 1983, contaminants above drinking water standards were discovered in samples collected from the Savage Municipal Well. Contamination was also detected in water samples collected from a separate water supply well for a nearby mobile home park. Use of both water supply wells was discontinued, a replacement well for the Town of Milford was constructed outside the impacted area, and the mobile home park was connected to the municipal water supply system. The Site was added to the EPA National Priorities List on September 1, 1984.
Following discovery of the VOC contamination in the Savage Municipal Well, EPA identified a group of local manufacturing facilities as potential sources of the contamination. Those facilities were the OK Tool Company (OK Tool), Hitchiner Manufacturing Company, Hendrix Wire and Cable, and New England Steel Fabricators, Inc.
The observed contaminant concentrations in shallow bedrock at the site and the lack of an adequate deep bedrock monitoring well network raised concerns that contamination from the site could migrate through bedrock fractures to nearby residential wells. This concern prompted the investigation and the characterization of the nature and extent of contamination in the bedrock aquifer.