Delaware Public Media

DNREC reaches settlement on clean up of contaminated Sussex Co. site

Apr 20, 2015

DNREC and Mallinckrodt Veterinary Inc. have reached a settlement regarding the clean up of a contaminated site in Millsboro.


Mallinckrodt Veterinary will pay DNREC $2.7 million dollars for the cleanup of its former poultry vaccine plant. That’s the largest settlement in the history of Delaware’s Hazard Substance Cleanup Act, a program run by DNREC’s site investigation and restoration section.

When the plant was operational, it used trichloroethylene, or TCE, which is a common solvent, but toxic to humans. TCE was used on site from 1952 to 1999.

Over the years, the contaminant had traveled through the soil into the groundwater.


DNREC Secretary David Small says that the levels of TCE in the local drinking water supply were higher than what the state’s Division of Public Health allows. They first detected high amounts in October 2005. At very high doses, TCE can be a carcinogen, but Small says the levels in drinking water Millsboro and Dagsboro, which shared Millsboro’s water supply, were nowhere near that.


“They were above the drinking water limit and could be a concern over time but we were able to work with public health and get filtration to clean up the drinking water,” said Small.


Small adds the Mallinckrodt site is an example that illustrates why their Hazardous Substance Cleanup Act program is necessary.

“You think we’ve characterized many of the sites around the state, but inevitably and unfortunately we continue to find new sites where there has been contamination in some cases for decades that in some cases just hasn’t shown up anywhere,” said Small.


 DNREC petitioned the EPA to investigate, and the agency is now looking for any remaining contaminants that may still be on the site.