Rosecrans Properties LLC, the responsible party for the Wauleco SNE Corp site in Wausau, has submitted a pilot test plan to shut down the site's pump-and-treat system. The September 2026 plan is now under review by the Wisconsin Department of Natural Resources and is available through the DNR's BRRTS site.
The system has operated for more than 35 years. In the plan, the responsible party's consultant says significant mass has been removed during that time and the system has entered a phase of diminished effectiveness.
Groundwater results remain high in places. One well, W40R, has recorded pentachlorophenol as high as 4,200 micrograms per liter in winter sampling, while Wisconsin's groundwater standard for the chemical is 1 microgram per liter. Citizens for a Clean Wausau says about 5,000 pounds of PCP still remain concentrated in an area smaller than one acre, more than 40 years after remedial work began.
In late October, Citizens for a Clean Wausau submitted comments to the DNR arguing that a shutdown would be premature. The group says the responsible party has not yet provided definitive proof that biodegradation is driving natural attenuation across the plume, that cleanup would reach state standards in a reasonable time, or that the pollution poses no risk to receptors if treatment stops.
The comments also point to a 2022 consultant presentation that estimated natural attenuation could take up to 95 years in some areas, and they question a recent Wisconsin River study that used a limited number of sediment and surface water samples. The group says pentachlorophenol from the site has discharged toward river wetlands near the Thomas Street bridge for years.
