04/16/2019- Tyco will suspend the discharge of their AFFF firefighting foam into Marinette’s sewer system beyond the 30-day request set by the City and into the foreseeable future. That update provided at Marinette’s Water and Wastewater Utilities Commission Monday. The flushing of the foam is believed to be the source of elevated PFAS levels in the city’s wastewater biosolids, which the Wisconsin DNR has required be held in storage tanks rather than spread on area agriculture fields as had been previously done. Those tanks are now nearing capacity and Water and Wastewater Operations Manager Warren Howard says further studies will need to be done on how PFAS concentrations are affected by the dewatering process of the sludge before can be sent to a landfill.
Marinette initially had their biosolids tested for PFAS by TestAmerica of California, but the DNR recommended samples also be run by Merit Lab in Michigan for However, Howard says the results from Merit Lab have not yet been released because the company is struggling to produce consistent, duplicated results due to the nature of the biosolids.
In addition to voluntarily ceasing the discharge of foam into the sanitary system, Tyco also plans to inspect and seal their own sanitary lines to prevent future infiltration of PFAS into the city’s wastewater treatment plant. Howard is hopeful that will allow the city to once again spread biosolids once it has been confirmed there’s no more existing contamination in their storage tanks or in any of the material coming in.