EPA Public Hearing on Proposed Remedial Action Plan for the Concord, Massachusetts Nuclear Metals, Inc. Superfund site
Wednesday, December 10, 2014
Acton Citizens for Environmental Safety (ACES) was incorporated in the late 1980s to (among other things) provide a forum through which Acton citizens could help safeguard the health of Town residents during the cleanup of the WR Grace site in Acton. ACES is currently in the process of merging with Green Acton, an environmental group in Acton working on similar environmental issues. I am submitting these comments on behalf of the soon-to-be-merged Green Acton/ ACES..
Acton’s population relies almost entirely on groundwater for its drinking water supply. The most productive wells are located in the Assabet aquifer, just across the Assabet River from the Nuclear Metals Superfund Site in Concord. Green Acton/ACES is very concerned about the potential for depleted and natural uranium, and chemicals such as volatile organic compounds (VOCs) and 1,4 dioxane, to migrate through the overburden and bedrock groundwater to the Assabet wells.
Although the Acton Water District has treatment on line for VOCs at the Assabet wells, this current treatment plant was not engineered to remove radiological contaminants, nor 1,4 dioxane, from the water. We are particularly concerned about 1,4 dioxane reaching Acton’s drinking water. This chemical is a suspected human carcinogen, known to affect the hepatic, ocular, and renal systems. Removal of this compound is difficult and expensive. To complicate the issue further, 1,4 dioxane is in regulatory limbo between Massachusetts and Federal health advisory levels.
We urge EPA to ensure that remediation efforts fully address the treatment and removal of these chemicals and halt their migration toward the Assabet Wellfield. We remind EPA that it is critically important at this stage to ensure that the nature and extent of contaminant plumes are clearly understood and delineated.
Without good knowledge of the extent of the plumes, a situation similar to what happened during the design of the WR Grace remediation system could occur. Hydrogeologists now suspect that the incomplete delineation of the extent of the VOC plume around the Industrial Landfill at the Acton/WR Grace site led to installation of treatment systems that did not capture the northeastern-migrating portion of the plume. This section of the plume, uncaptured, continued to migrate along the groundwater gradient toward Acton’s School Street Wellfield. Chemicals from the plume were eventually detected in the School Street Wellfield, necessitating separate remediation efforts decades after the original remediation was installed at the Industrial Landfill.
We strongly encourage EPA to require an efficient and thorough characterization of the plumes migrating from the Nuclear Metals site and a full remediation of the harmful chemicals in these plumes. This is Acton’s most important groundwater source, on which thousands rely. Please protect it!