Despite a Michigan Court of Claims order issued in November siding with 3M that the State of Michigan did not follow the required administrative procedures when establishing PFAS groundwater cleanup rules, the rules can continue to be used and remain active.

“The interests of public health weigh in favor of this stay, so that the parties can pursue appellate relief and the Department can consider, if it wishes, whether additional regulatory actions should be taken in the meantime,” Judge Brock Swartzle said in the Court Order.

While Judge Swartzle’s order invalidates the groundwater cleanup rules, the order was stayed and the PFAS groundwater cleanup rules remain in effect. The judge’s ruled that the state did not account for costs to businesses during the administrative process of promulgating the PFAS cleanup rules. The ruling was made in response to a suit brought forward by 3M against the State of Michigan in May 2021.

The State of Michigan’s groundwater clean-up rules for PFAS compounds for seven PFAS compounds were officially added to the groundwater clean-up rules by the Michigan Department of Environment Great Lakes and Energy (EGLE). The generic clean-up criteria (GCC) for the seven PFAS compounds are as follows:

• Hexafluoropropylene oxide dimer acid (HFPO-DA) 0.370 ppb

• Perfluorobutane sulfonic acid (PFBS) 0.420 ppb

• Perfluorohexane sulfonic acid (PFHxS) 0.051 ppb

• Perfluorohexanoic acid (PFHxA) 400 ppb

• Perfluorononanoic acid (PFNA) 0.006 ppb

• Perflurooctanoic acid (PFOA) 0.008 ppb

• Perfluorooctane sulfonic acid (PFOS) 0.016 ppb

In addition to the groundwater clean-up criteria, EGLE also established groundwater surface water interface criteria (GSI) for PFOA (12 ppb) and PFOS (0.012 ppb). EGLE’s updated groundwater rule expands upon rules approved in 2020 by the Environmental Rules Review Committee, which established standards for safe water at public water supplies for PFAS.

Merit Laboratories is a leading national PFAS environmental laboratory, analyzing drinking water, soil, wastewater, groundwater, and other sample matrices, including biosolids and sludge. Analytical methods performed by Merit for PFAS include drinking water by EPA 533, EPA 537.1, and EPA 537 rev. 1.1, biosolids by ASTM D7968-17 with Isotopic Dilution, and soil, wastewater, groundwater, and surface water by ASTM D7979-19 with Isotopic Dilution and ASTM D7968-17.