Demolition Area 2The Demolition Area 2 (Demo 2) site, located in the north-central portion of Camp Edwards, was used from the late-1970s to the late-1980s for light demolition-training activities involving explosive charges of less than 10 pounds. Demolition training activities took place in a shallow, cleared depression flanked by a U-shaped berm. In 2004, a soil removal action excavated and treated approximately 1,200 tons of soil from the berm and a 30-foot area at the center of the site that were the source of groundwater contamination migrating from Demo 2. In 2010, EPA issued a Decision Document that selected a comprehensive remedy for the Demo Area 2 site. The remedy consisted of No Further Action for the source area and Monitored Natural Attenuation and Land Use Controls for groundwater. The Decision Document predicted that hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) concentrations would attenuate to below the 2 parts per billion (ppb) Health Advisory by 2011 and the 0.6 ppb 10-6 risk based level by 2013. RDX concentrations in groundwater samples collected in 2013 still exceeded the 0.6 ppb remedial action goal at three locations meaning that restoration was not achieved by the original predicted date. Therefore, the timeframe to achieve aquifer restoration at Demo Area 2 is longer than was predicted and an addendum to the Decision Document is required. The Decision Document Addendum modifies the 2010 Decision Document to present a new prediction for the year when the aquifer will be restored (2 ppb by 2016 and 0.6 ppb by 2018) and a modification to the monitoring program which includes the installation of two downgradient groundwater monitoring wells to assess the extent of contamination along the base boundary. To obtain more information about this site, click here To view a map of the Demo 2 site and plume, click here. A Decision Document is available for this site. Click here for more information. For information on where to find documents related to this site and the program, click here. |
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RDX - Royal Demolition Explosive; Royal Dutch Explosive; Research Department Explosive - A white crystalline solid used as an explosive
HMX - High Melting Explosive; Her Majesty’s Explosive
A body of groundwater that contains contaminants in excess of amounts allowed by law; the plume is defined by multiple samples from multiple monitoring wells