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Future Events
They Only Thought They Were Done
Since the early 1980s, the federal law known as "Superfund" has required companies to
clean up property sites that are contaminatedby hazardous waste. So far, hundreds of sites
have been cleaned up (or "remediated," in Superfund terminology), at a collective cost
that runs to the billions of dollars; hundreds of other sites are still in the process of being
decontaminated. Superfund cleanups usually take years to complete, and often involve
expensive legal wrangling among the parties involved.
A large number of Superfund sites-including some where
cleanup has been completed-have been found to contain
trichloroethylene (TCE), a widely used solvent. To compli-
cate matters further, the United States EnvironmentalProtection
Agency (BPA)has now discovered that TCE may be far more
toxic than originally thought.
Moreover,the cleanup techniquesused in the past to remove
the substance from groundwater may actually have made the
problem worseby causingTCE to be emitted in vapor form. This
vapor can concentrate in buildings and other enclosed spaces,
increasingthepotentialtoxicityevenfurther..
EPA is now studying whether previously cleaned Super-
fund sites should be "reopened" for additional remediation of
TCE. The decision is made more difficultby the fact that some
previously cleaned sites have been sold since the Superfund re-
mediation was finished, and may havehad buildings constructed
on them..