The Baker administration is supporting efforts to have the U.S. Environmental Protection Agency designate the Lower Neponset River as a Superfund site for environmental clean-up. This is the latest in years worth of work between the EPA, Massachusetts Department of Environmental Protection and local advocacy groups to review the extent of the river's pollution and the necessary steps to remove the contamination.
The 3.7-mile stretch of river runs through Milton and the Boston neighborhoods of Hyde Park, Dorchester and Mattapan. It is contaminated with polychlorinated biphenyl chemicals — or PCBs — which have been linked to several health hazards, including reproductive issues. Those concentrations are especially high near the Tileston and Hollingsworth Dam in Hyde Park and the Baker Dam in Milton/Lower Mills.
"The serious nature of the contamination at this site warrants its inclusion on the National Priorities List [NPL]," said Gov. Charlie Baker in a letter sent last month to the EPA. In order to receive federal Superfund resources, a clean-up site must be listed on the NPL.
The PCBs in the Neponset are the product of centuries worth of industrial sites. The chemicals bind to organic materials; in the lower Neponset they are trapped in the river's sediment. That makes it relatively safe for recreation like boating and catch-and-release fishing, but not for extended contact with the river bed.
"What you don't want to do is come into contact with the thick black mud at the bottom of the river in these high concentration areas," said Kerry Snyder, advocacy director for the Neponset River Watershed Association. "You also don't want to eat the fish that you catch, and that goes for any fish that are caught between, say, Walpole to the Baker Dam."
The Baker administration anticipates the EPA will propose adding the site to the National Priority list, which will then trigger a public comment period. The EPA will review those comments before issuing a final decision on the site's status.
"We are actively considering — there [are] more steps that need to be done but we are very much in favor of it here in EPA New England," said Deborah Szaro, Acting Regional Administrator for EPA Region 1, "and we are advocating for it nationally at EPA headquarters."