Since the initial potable well sampling, the DNR and City of Manitowoc have expanded potable well sampling. Additional potable wells north, west and south of the Gravel Pit have been sampled to ensure that impacted groundwater is not moving in those directions. Potable wells in the direction of groundwater flow to the southeast, east, and northeast of the Gravel Pit have been sampled to aid in defining the extent of groundwater contamination.
As of December 2016, approximately 80 potable wells have been sampled. Twenty wells, including the original three from 2013, had vinyl chloride detected in an amount exceeding DNR drinking water standards. There are also several wells with low level detection of cis-1,2-dichloroethene in an amount far below DNR drinking water standards. Sample results from the other potable wells showed no detection of chlorinated solvent compounds. All property owners have been notified of their potable well results. The properties with detection above DNR drinking water standards have been provided with temporary alternative safe water supplies until a permanent solution can be implemented. Eighteen of the twenty impacted properties have a permanent solution in place at this time. Potable well sampling will continue throughout 2017 and into the foreseeable future.
For more information regarding potable well water click on the links below: