By Shereen Siewert
Weston shut down two wells after the latest round of voluntary testing showed toxic chemicals above the Wisconsin Department of Health Services recommended limit in the village’s drinking water, officials said Thursday.
In February, village officials announced they would retest water for PFAS, an emerging contaminant that was also discovered in Wausau’s drinking water. The prior round of sampling in Weston, performed in 2014 and 2015, did not find PFAS above the reporting limits of 20 parts per trillion in any of the utility’s six wells. But new testing, performed March 3, showed significant contamination at the treatment plant, prompting the shutdown.
The highest level of PFAS discovered this month were in well 3, at 38.73 parts per trillion, giving the well a Hazard Index value of 2.75. The treatment plant for wells 3 and 4 showed a combined level of 25.91 ppt, with a Hazard Index of 1.88.
“Upon learning these sample results the Village of Weston Water Utility shut down the Treatment Plant, taking wells 3 and 4 off-line, on Thursday March 17, 2022,” officials said, in a news release and during a press conference held this morning. “This action was taken after consultation with the Wisconsin DNR and DHS.”
Total PFAS (PFOA and PFOS) levels and Hazard Index values for the water pumped to the distribution system from the Utility’s other wells are below the recommended health advisory standards of 20 parts per trillion and 1.0, respectively. Officials are coordinating additional PFAS sampling to confirm the current results.
Village officials acknowledge the shutdown is only a short-term solution and said depending on demand, one of the two closed wells would need to be turned back on. Customers will be notified if that happens, officials said.
In response to the situation, village staff is working with the Wisconsin Department of Natural Resources, DHS and the Marathon County health department and listed the following solutions proposed:
- Keep wells 3 and 4 off-line as much as possible.
- Modify piping to blend well 4 with distribution system water prior to well 4 pumping to the distribution system through the treatment plant. This concept has been discussed with DNR and the Village’s engineering consultant. We feel this will be the most favorable short-term solution.
- Complete proposed Wells 7 and 8 for additional supply of drinking water to meet all drinking water standards. This project is a long-term need of the Village that was being addressed and, coincidentally, is nearing construction stage as PFAS has become a common topic. The well construction component of this project is currently advertised for bids.
- Add granular activated carbon (GAC) removal at the treatment plant. The treatment plant is designed and pre-piped for adding GAC. Unfortunately, we are told that equipment for this treatment process may not be available for 40 months or more.
- Continue working to implement our short and evaluate long-term projects.
- Additional sampling
Weston is not violating any drinking water standards or regulations, but the Environmental Protection Agency is widely expected to issue a federal standard this fall of 20 ppt or below, based on ongoing data. Though surrounding states have already passed statewide standards, Wisconsin has not. The Natural Resources Board, by a vote of 6-1, approved a drinking water standard of 70 ppt, more than triple the level recommended by DHS. The decision has been sharply criticized by environmental and health advocates. The NRB also left groundwater unregulated during their Feb. 23 meeting.
Based on the shutdown, Weston is not recommending any changes in drinking water use for residents, and state and local health officials concur with that recommendation.