Recently-released test results reveal that old hazardous waste disposal sites inside Badger Army Ammunition Plant are continuing to impact groundwater, prompting area residents to ask for a more proactive approach to cleanup and improved public outreach.
Citizens for Safe Water Around Badger (CSWAB) is asking that the Army reinstate regular testing of certain drinking water wells located in the path of a groundwater contaminant plume that has migrated beyond the southern plant boundary and is discharging to the Lower Wisconsin Riverway at Prairie du Sac. The group is also recommending that steps be taken to identify and better control the sources of persistent groundwater contamination in the Towns of Merrimac and Sumpter.
According to state health officials, all residential wells tested by the Army continue to be safe to use. However, several residential wells south of Badger have been completely dropped from regular testing by the Army. CSWAB believes this testing should be reinstated because groundwater monitoring wells south of the plant boundary are detecting high levels of ethyl ether and groundwater conditions are expected to change as portions of the groundwater cleanup system are shut down. In September 2014, ethyl ether was detected in groundwater beyond the plant boundary at 3,200 parts per billion (ppb). The health-based standard for ethyl ether is 1,000 ppb.
In late 2014, Army testing detected the explosive DNT at concentrations more than 100 times the groundwater standard at the northeast corner of Badger in the Town of Merrimac. The exceedances in this and other nearby groundwater monitoring wells indicates that the landfill cap installed at the Deterrent Burning Grounds more than a decade ago is not effectively preventing soil contaminants from migrating to groundwater. Outside the plant boundary, a groundwater monitoring well at Weigand’s Bay North detected DNT at 0.041 ppb, approaching the health-based groundwater standard of 0.05 ppb.
At the southeast portion of Badger, CSWAB is asking that the Army be required to locate the source of a groundwater contaminant plume which has moved beyond the plant boundary at Gruber’s Grove Bay in the Town of Sumpter. Test results in September and November of 2014 indicate that DNT was detected in groundwater above health-based standards. The Army has yet to define the origin of this Central Plume, preventing active cleanup at the source.
Closer to the Baraboo Hills at the northwest corner of the plant, CSWAB is asking that the Army be required to identify another unidentified source of explosives contamination in groundwater. Like other areas at Badger, the principal contaminant of concern is DNT. Detected levels were as high as 0.094 ppb, exceeding the groundwater standard of 0.05 ppb for total DNT. DNT is considered a probable human carcinogen based on findings of cancer in animal studies. Groundwater monitoring has been discontinued altogether in this area, according to recent Army reports.
Given these considerations, CSWAB has asked the Wisconsin Department of Natural Resources to host a public informational meeting on groundwater conditions in and near Badger. In the interim, CSWAB has published two maps showing a summary of groundwater exceedances and changes in groundwater monitoring.
Map Groundwater Exceedances Sept-Nov 2014
Dec 2014 New Groundwater Overview posted by WDNR
BACKGROUND: The Deterrent Burning Grounds area was used by the Army as a demolition debris landfill and for the open burning of explosive wastes, structural timbers, asphalt shingles, cardboard, papers, and office waste. In 1999 and 2000, the top 15 feet of contaminated soil in the pits was removed and disposed off-site. A landfill cap was installed over the area in 2003. A passive biotreatment system was removed and the cap restored to an impervious condition in 2012, according to the Army’s Installation Action Plan for Badger. The Deterrent Burning Grounds area is located in the northeast corner of Badger in the Town of Merrimac.