After a grueling 6-month clean-up, Iowa DNR and the US EPA approved closure for the emergency mercury spill response action at Dubuque Water Pollution Control Plant as closed for no further action today. The incident originally occurred September 23, 2010 when workers dissembling two old center pivot bearings in two trickling filter tanks spilled the mercury while removing the bearings over a large area of fractured 4”-6” granite in the former trickling filter tanks and outside the tanks to a lower staging area.
Its estimated NSEC recovered more than 1 gallon of elemental mercury during the clean up, much more than the September estimate of roughly two tablespoons. The elemental mercury recovered was a combination of historical and spilled mercury. The spill is believed to have been the largest on-site mercury chemical decontamination project completed in the United States.
posted on June 6, 2011 by
