The Town of Ayer Grove Pond Wellfield provides approximately 60% of the Town’s water supply. Due to the wellfield’s proximity to Devens, the Army Corp. of Engineers sampled the wells for an unregulated contaminants PFOA and PFAS in September 2016. The results at the Grove Pond Wells were positive for these compounds with Well 8 aver the EPA “heath advisory” level. As the water from the three wells in the wellfield is mixed prior to treatment and distribution into the town, the water supply is below the health advisory limit. However, this is an issue that the DPW and MassDEP are monitoring and The DPW is developing an action plan in case the contamination levels increase.