Water quality by county
in Maine
EPA sampled public water systems across Maine for PFAS under its UCMR 5 programme. Of the 16 counties, 5 have a reading above a federal limit and 2 have not been sampled at all — which is not a clean result, only an absence of one. Each county below shows what was found, at what concentration, and at which utility.
| county | Population | Worst result | Compound |
|---|---|---|---|
| Cumberland County | 313,809 | 2.3× | PFOA · 9.2 ng/L |
| York County | 220,143 | 1.8× | PFOS · 7.1 ng/L |
| Kennebec County | 128,461 | 1.6× | PFOA · 6.4 ng/L |
| Androscoggin County | 115,272 | 1.3× | PFHxS · 13.2 ng/L |
| Aroostook County | 66,776 | 1.2× | PFOS · 4.8 ng/L |
| Hancock County | 56,946 | under the limit | PFHxS · 3.3 ng/L |
| Franklin County | 30,902 | under the limit | — |
| Knox County | 40,981 | under the limit | — |
| Lincoln County | 36,491 | under the limit | — |
| Oxford County | 60,039 | under the limit | — |
| Penobscot County | 156,840 | under the limit | — |
| Piscataquis County | 17,432 | not sampled | — |
| Sagadahoc County | 37,582 | under the limit | — |
| Somerset County | 51,338 | under the limit | — |
| Waldo County | 40,617 | under the limit | — |
| Washington County | 31,383 | not sampled | — |