Many public and private drinking water wells in Horsham, Warminster and Warrington were shuttered in 2016 after testing showed high levels of the chemicals.
The EPA set a lifetime health advisory limit of PFAS exposure at 70 parts per trillion that year, but public drinking water wells in the three local communities saw levels 100 times higher in some cases.
The military has acknowledged the contamination was likely caused by the use of firefighting foams at active and former military bases in the area, and agreed to pay residents for their upfront remediation costs.
That offer did not extend to wells that tested under the EPA limit, but many residents demanded their drinking water be free of any detectable PFAS levels.