New Hampshire and Michigan Set PFAS Drinking Water Limits

Associated Press (AP) reported that New Hampshire House Bill 1264 has become law setting some of the nation's toughest drinking water standards for per- and polyfluoroalkyl substances (PFAS). The law sets a drinking water standard for each of four perfluorochemicals; 12 parts per trillion (ppt) for Perfluorooctanoic acid (PFOA), 15 ppt for Perfluoroctanesulfonic acid (PFOS), 18 ppt for Perfluorohexanesulfonic acid (PFHxS), and 11 ppt for Perfluorononanoic acid (PFNA). The US Environmental Protection Agency (EPA) has established the health advisory level at 70 ppt.

The New Hampshire Department of Environmental Services (NHDES) had previously adopted rules in 2019 that established the more stringent levels as maximum contaminant levels (MCLs) for drinking water and ambient groundwater quality standards (AGQS). However, effective December 31, 2019, the Merrimack County Superior Court issued a preliminary injunction barring enforcement saying NHDES failed to consider cost and benefits of the rules. The new law is a response to that injunction.

On July 22, 2020, the Michigan Department of Environment, Great Lakes, and Energy (EGLE) announced new limits for PFNA at 6 ppt, PFOA at 8 ppt, PFOS at 16 ppt, and PFHxS at 51 ppt. Michigan also adds standards for Hexafluoropropylene oxide dimer acid (HFPO-DA) ammonium salt with trade name GenX at 370 ppt, Perfluorohexanoic acid (PFHxA) at 400,000 ppt, and Perfluorobutane sulfonate (PFBS) at 420 ppt.

The rules passed the final oversight step in the rule-making process with the Michigan Legislature's Joint Committee on Administrative Rules (JCAR) and are expected to become effective August 3, 2020.