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Reference News Release: Settlement for Cleanup at Iron Horse Superfund Site in Massachusetts

Release Date: 10/07/2014
Contact Information: David Deegan, (617) 918-1017

BOSTON – EPA and the U.S. Dept. of Justice have reached a $4.2 Million settlement with Boston and Maine Corp. (B&M) and the Massachusetts Bay Transportation Authority (MBTA) for partial reimbursement of EPA’s past costs, and for full payment and performance of future cleanup work at the Iron Horse Park Superfund Site, Operable Unit 4, in Billerica, Mass.

The settlement between the parties calls for B&M and MBTA to perform the $2.7 million remedy identified in EPA’s 2011 “Record of Decision” for Operable Unit 4 on the site, as modified by the 2014 Explanation of Significant Differences. The remedy addresses site-wide groundwater and localized sediment contamination. The two companies will also pay 100 percent of EPA’s interim and future response costs (including oversight costs), and approximately $1.5 million of EPA’s past costs associated with OU4.

“EPA is very pleased to reach a settlement ensuring that future cleanup costs to address contamination at Iron Horse Park is not borne by U.S. taxpayers, but rather by responsible parties,” said Curt Spalding, regional administrator of EPA’s New England office. “We are looking forward to ensuring that cleanup work at this site continues.”

Iron Horse Park, a 553-acre industrial complex which includes manufacturing and rail yard maintenance facilities, is located in North Billerica, Mass. The site includes open storage areas, and former landfills and wastewater lagoons. The site contains contaminated soil, groundwater and sediment.

The site was listed on the National Priorities List (aka, Superfund list) in 1984. In 1997, EPA determined that site-wide groundwater, surface water and sediment should be addressed as a fourth Operable Unit. Work to address other contamination at the site was conducted under two previous operable units, and work on the third operable unit is ongoing. The cleanup decision by EPA on necessary remedial actions for Operable Unit 4 is contained in the July 25, 2011 final “Record of Decision” and an “Explanation of Significant Differences” document dated July 22, 2014. Contaminants detected most frequently include volatiles, semi-volatiles, pesticides, polychlorinated biphenyls, asbestos and metals.

The remedy includes excavation of contaminated sediment in B&M Pond, monitored natural recovery of contaminated sediment in other locations, and long-term monitoring of contaminated groundwater.

More information:

The Consent Decree will be available for public review and comment for 30 days, following posting on the Dept. of Justice Web site:

EPA work to clean up the Iron Horse Park Superfund Site: