Draft rules limiting per- and polyfluoroalkyl substances (PFAS) contamination in Michigan drinking water moved forward in the state rule-making process last week when the Environmental Rules Review Committee (ERRC) approved them.
Among the most stringent and comprehensive PFAS standards in the nation, the proposed rules will provide provisions reducing exposure to seven PFAS compounds in drinking water. The provisions include establishing drinking water standards, sampling requirements, public notification requirements, and laboratory certification criteria. The seven PFAS limits covered under the proposed rules are:
|Specific PFAS||Drinking Water Maximum
Contaminant Level (MCL)
|PFNA||6 ng/L (ppt)|
|PFOA||8 ng/L (ppt)|
|PFHxA||400,000 ng/L (ppt)|
|PFOS||16 ng/L (ppt)|
|PFHxS||51 ng/L (ppt)|
|PFBS||420 ng/L (ppt)|
|HFPO-DA (GenX)||370 ng/L (ppt)|
Michigan took the proactive step to set limits on PFAS compounds after contamination was discovered in several drinking water supplies throughout the state. These investigations were led by the state's multi-agency Michigan PFAS Action Response Team (MPART).
MPART also coordinated with an independent science panel of national PFAS experts who in 2018 advised the state that the US EPA's health advisory level of 70 parts per trillion (ppt)for two compounds, PFOS and PFOA, was not protective of public health. With federal drinking water standards still several years away, Gov. Gretchen Whitmer in 2019 directed EGLE and MPART to review the scientific and health data currently available on PFAS compounds and move forward with state drinking water standards.
The next step in the rulemaking process involves EGLE forwarding the draft rules and supporting documents to the Michigan Office of Administrative Hearings and Rules (MOAHR), and then on to the Joint Committee on Administrative Rules (JCAR). JCAR is bipartisan legislative committee comprised of five house and five senate members.
The rules must be before JCAR for 15-full session days. During those session days, JCAR may take several actions, including waiving the session days and allowing the rules to proceed to promulgation, requesting changes be made to the rules, or taking legislative actions regarding the ruleset.
If no action is taken, the rules will move to promulgation and will be filed by the MOAHR with the Office of the Great Seal.
Under the current timeline a final rule could be adopted in late April or early May 2020.
The new rule would allow municipalities to integrate PFAS testing into their existing water quality monitoring and allow EGLE to redeploy staff and financial resources to other PFAS and emerging contaminant investigations throughout the state. In 2018 EGLE tested every municipality, school, and tribal water system in the state and has maintained quarterly and, in the case of lake and stream water intakes, monthly monitoring over the past two years.
If the new rules are adopted, quarterly sampling requirements will be phased in with drinking water supplies. EGLE will determine PFAS levels based on a running average of the four previous quarterly sampling results. A system whose average result over four consecutive quarters is above any of the PFAS drinking standards would immediately be out of compliance under the new rule.
Drinking water systems demonstrating consistent non-detections for the seven regulated PFAS compounds, may eventually move to annual testing for the compounds.
An exceedance of new PFAS standards would require systems to issue a public notice within 30 days including mandatory health effect language. Community water supplies must also report PFAS standard violations in their consumer confidence reports.
EGLE does not plan to immediately issue fines for non-compliance during the initial roll-out of the new rules. To help systems reach compliance, EGLE will enter into Administrative Consent Orders (ACO) with drinking water systems establishing a timeline for achieving compliance. The ACOs will also stipulate fines if compliance deadlines are missed.
Michigan law Part 201 specifies that if a state drinking water standard is created for a chemical that has an existing groundwater cleanup criterion, then the new state drinking water standard for that chemical becomes the state's groundwater cleanup criterion.
Given that Michigan currently has groundwater cleanup criteria for PFOS and PFOA separately or combined of 70 ppt, the new drinking water rules would lower the groundwater clean-up criterion to 8 ppt for PFOA and 16 for PFOS.
Existing Rule 57 surface water quality standards covering lakes and streams would not change as a result of the proposed drinking water standards.
Information about the draft rule can be found on the Environmental Rules Review Committee website.