Although Grace employees did dispose of TCE on the Woburn plant site, the chemicals never reached Wells G and H, about one half mile away, during the time that the wells were operating. According to the Defendant's hydrogeologic expert, the migration of contaminants introduced at Grace's property was very gradual, and was inhibited by an effective barrier - a section of low-permeability sediments found between Grace and Wells G and H.
Photograph from the collection of Professor Scott Bair, Ohio State University.
[Source: http://www.geology.ohio-state.edu/courtroom/ram-lg.JPGs]