|Barges in the Pine Street Superfund Site.|
Pine Street Canal Superfund site still active.Old, cleaned up or contained contamination sometimes resurfaces to create new problems. The Pine Street Canal in Burlington, Vermont, was once home to a coal gassification plant. For almost 60 years "plant wastewaters and residual oil and wood chips saturated with organic compounds were directly discharged or disposed of in the Pine Street Canal wetland.
During the 1960s and 1970s oily material seeping to the surface alerted authorities and tests showed high levels of polyaromatic hydrocarbons, benzene, tuolene, xylenes and other volatile organic compounds related to coal tar. At that time the concern was these contaminants would make their way into Lake Champlain, the community's source of drinking water, according o the EPA's background on the site.
Site wide cleanup activities followed emergency cleanup efforts and the record of decision listed capping and sealing contaminated sediment in the canal, the turning basin and adjacent wetlands. Administrative controls rounded out the plan. By 2009 though, the original cap was not holding back seepage of the contaminants at the canal's south end so a second cap was proposed. That cap will also fill up, so at the same time passive recovery wells need to be drilled to catch contaminates that can be pumped and treated.
According to a report in Bloomberg Bussinessweek, the EPA is amending its plan to cap the southern end of the canal by also adding an underground vertical barrier and it is looking for public comments on that new plan. This cleanup started in 1985, nearly 20 years after the contamination was discovered.