While the U.S. Environmental Protection Agency (EPA) has issued preliminary determinations to regulate PFOA and PFOS, they have not established Maximum Contaminant Levels (MCLs) for per- and polyfluoroalkyl substances (PFAS).
Accordingly, states continue to establish their own regulatory limits for PFAS. In many instances, the states’ limits are far more stringent than the EPA’s current advisory levels.
Michigan PFAS Limits
Michigan has adopted some of the lowest/strictest standards in the United States (Michigan Adopts Strict PFAS Standards). Some of the new PFAS standards in Michigan include: PFOA (8 parts per trillion [ppt]), PFOS (16 ppt), and PFNA (6 ppt).
Further, as we outlined in our regulatory update, “The new drinking water standards also have an immediate effect on Michigan’s existing groundwater clean-up criteria of 70 ppt for PFOS and PFOA. The new groundwater standard will be 8 ppt for PFOA and 16 ppt for PFOS.”
These limits were developed based on recommendations from the Michigan PFAS Action Response Team (MPART). According to the Department of Environment, Great Lakes, and Energy, MPART, “…conducted a year-long review of current scientific and health data about PFAS and consulted several academic, environmental and business stakeholders in the development of the rules.”
New York PFAS Limits
According to Bloomberg Law, “New York set its levels at 10 ppt for both PFOA and PFOS, the two most well-studied chemicals in the PFAS family. They require public water systems to test for the contaminants, and clean them up if elevated levels are detected.”
Once approved by the New York State Health Commissioner, the regulations will be published in the State Register. Also according to Bloomberg, “Public water systems in New York serving 10,000 people or more will be required to start testing within 60 days. Systems serving between 3,300 and 9,999 people would have to begin within 90 days of the regulations being published, and those serving a population of less than 3,300 have six months.”
Remediation of PFAS
Dragun’s senior environmental engineer, Matthew Schroeder, is actively involved in PFAS groundwater remediation projects. I asked Matt what his opinion was with respect to the limits in Michigan and New York.
Are there unique environmental remediation challenges when addressing PFAS in groundwater at these low levels?
PFAS are challenging to remediate for a couple of reasons. In situ remediation of PFAS-impacted groundwater is limited, because PFAS don’t break down readily in the environment (hence the nickname “Forever Chemicals”). In situ remediation of PFAS is currently limited to adsorption using activated carbon. In addition, PFAS travel more quickly than many other contaminants. The low standards will expand the area that requires remediation in many PFAS groundwater plumes.
Most groundwater remediation consists of activated carbon or ion exchange resin in ex situ systems (pump and treat). With these low standards, the carbon or ion exchange media will need to be replaced much sooner, increasing the operating cost of the remediation systems.
In Michigan, the criteria went from 70 ppt to 8 ppt for PFOA. Does this require any additional sampling precautions?
Special precautions are necessary for PFAS sampling to avoid cross contamination of the samples. PFAS are in many consumer products (rain gear, cosmetics, work boots, etc.) and equipment (anything with Teflon), and because the PFAS standards are a thousand times less than standards for many common contaminants, care must be taken to avoid using any of these products during the sampling. The lowering of these standards amplifies the concern about cross contamination during sampling.
Are laboratories able to reliably detect PFAS at these levels?
Laboratories are commonly able to identify and quantify approximately 30 PFAS at a detection limit of 1-2 ppt. Although these detection limits are lower than the new Michigan standards, these standards are approaching the limit of the technical capability of the laboratory methods.
It’s likely that there will be additional steps taken by states to establish enforceable standards. For more information on state PFAS developments, see Bloomberg’s PFAS State Activity Tracker.
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