The District of Columbia has released the first steps of a plan to clean up a legacy of toxic contaminants on the bottom of the Anacostia River.I was involved in measuring the heavy metals and toxic organics in the sediments of the Anacostia back in 2003. It was apparent then that the fine sediments of the river were heavily contaminated at different points of time in the past, depending on the pollutant, and that, while inputs had been reduced, and new sediments being deposited, while cleaner, were still contaminated. Certainly removing the contaminated sediments, or capping highly contaminated areas (which may depend on how much depth you have) will be an improvement, but it will be an expensive fix.
The “early action” plan calls for capping, dredging and monitoring contaminated sediment at nearly a dozen “hot spots” along a highly urban and historically industrial nine-mile stretch of the river, which flows from suburban Maryland through the nation’s capital.
The District Department of Energy and Environment will hold the first of several public meetings to explain the proposed plan on Thursday, Jan. 23, from 6:30 to 8:30 p.m. The public comment period for the plan was extended to March 2, with additional meetings to be held on Jan. 27 and Feb. 3.
After the comment period, DOEE says it will issue an interim record of decision by September. The agency plans to hire contractors to begin the work sometime this year. The cleanup is expected to take several years.
The department’s proposed plan maps out 11 “early action areas” located in the river’s main stem, plus Kingman Lake and Washington Channel, where sediments containing toxic contaminants will be removed, capped or treated with activated carbon. These areas contain the highest concentration levels of polychlorinated biphenyls (PCBs), now-banned chemicals once widely used as coolants or insulators in electrical equipment that are now associated with cancer and other health effects.
The main ways people would be exposed to these contaminants is by wading or swimming in the river or by fishing and eating contaminated fish tissue. It is currently illegal to swim in District waters, and anglers are advised to limit their consumption of locally caught fish, especially bottom-feeders from some portions of the river. But a 2013 report found that many residents consume significant amounts of fish caught in the Anacostia anyway. Fish, aquatic insects and other wildlife also are impacted by the chemicals in the river’s sediment, which can become resuspended in the water when the bottom is stirred up.
The proposed plan predicts the work will yield a 90% reduction in people’s risk of exposure to PCBs from eating contaminated fish. “The idea here is that if we clean up the most contaminated areas, the presumption is you’re reducing the risk,” said Dev Murali, remedial project manager with the District. Follow-up monitoring is planned to gauge the cleanup’s effectiveness.
The project is estimated to cost about $30 million. The District government is funding the first steps of the sediment cleanup, though the city will likely seek to recover remediation costs from companies and federal agencies that contributed to the pollution.
I wish them good luck