A new environmental study has confirmed that groundwater contamination from an old hazardous waste dump at Badger Army Ammunition Plant has moved beyond the plant boundary and is discharging into Lake Wisconsin at Weigand’s Bay. Concentrations of the carcinogenic explosive DNT exceed state groundwater standards and low levels of solvents may have also migrated outside the plant. So far, contaminant concentrations in two affected drinking water wells are below health advisory levels.
The Army’s December 2009 groundwater investigation recommends that additional shallow and deeper monitoring wells be installed in three rural neighborhoods at Weigand’s Bay to monitor DNT and solvent concentrations and contaminant trends. The new well locations will be discussed with the WDNR, the report says.
The primary source of the groundwater contamination is the Deterrent Burning Ground – a closed hazardous waste disposal site located in the northeast corner of Badger. It was used as a demolition landfill and for open burning of deterrent, asphalt shingles, building timbers, and office wastes. Deterrent is an organic liquid containing dibutyl phthalate and DNT that is used to modify the burning characteristics of nitrocellulose-based propellants.
In September 2009, groundwater testing at the Deterrent Burning Ground detected DNT at 3.8 parts per billion (ppb) in groundwater which is 76 times higher than the safe drinking water advisory of 0.05 ppb.
Area residents do not feel the recommendations go far enough. “The Army should be taking steps to evaluate the cleanup remedy,” said Laura Olah, a Weigand’s Bay resident and Executive Director of Citizens for Safe Water Around Badger. “There is nothing in the plan to prevent further contamination of drinking water and the environment.”
A 2009 technical review by the U.S. Army Corps of Engineers confirms that Badger does not have a method in place to determine if operation of the on-site bioremediation system could be affecting groundwater contamination and migration. If the current cleanup remedy is found not to be effective, the Corps identified a number of alternative cleanup methods that could help remedy the problem.
The Deterrent Burning Ground, Landfill #3, and Landfill #5 are also potential sources of volatile organic compounds (VOCs) in groundwater, the report says. All are located approximately 1.5 miles northwest (upgradient) of Weigand’s Bay.
The Army sampled private wells in the Weigand’s Bay area for volatile organic compounds twice during 2007. The carcinogenic solvent trichloroethylene (TCE) was detected in five private wells; none of the detections were above safe drinking water standards. The Army said that the source of the TCE is not known however the parent product perchloroethylene (PCE) has been detected in groundwater at Badger.
Certain forms of DNT are harmful to aquatic organisms and may cause long-term adverse effects in the aquatic environment. The Army report does not discuss potential harm to wetlands and fisheries.