On June 19, 2018, the Massachusetts Department of Environmental Protection (DEP) Bureau of Waste Site Cleanup (BWSC) issued its Interim Guidance on Sampling and Analysis for PFAS at Disposal Sites Regulated under the Massachusetts Contingency Plan (MCP Guidance). This follows the June 8, 2018 guidance, Final Recommendations for Interim Toxicity and Drinking Water Guidance Values for Perfluorinated Alkyl Substances Included in the Unregulated Chemical Monitoring Rule 3 (Drinking Water Guidance), from the DEP Office of Research and Standards (ORS). These documents were the result of an effort across DEP programs, which began in February 2018, to address the lack of enforceable federal standards for per- and polyfluoroalkyl substances (PFAS) in drinking water.
Previously, in 2016, the U.S. Environmental Protection Agency (EPA) published a health advisory for two PFAS chemicals: perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) at 0.070 micrograms per liter (μg/L) or 70 parts per trillion (ppt). EPA convened a national summit on May 22-23, 2018 with state stakeholders, although many states like Massachusetts were moving ahead without direct EPA involvement. More recently, the U.S. Department of Health and Human Services' Agency for Toxic Substances and Disease Registry (ATSDR) finally released a 852-page draft for public comment of its Toxicological Profile for Perfluoralkyls on June 20, 2018. Comments are due July 23, 2018. It remains to be seen how ATSDR's draft will impact the work already underway in Massachusetts and other states.
The Massachusetts ORS Drinking Water Guidance established a guideline to include PFOA, PFOS and three additional PFAS chemicals—perfluorononanoic acid (PFNA), perfluorohexanesulfonic acid (PFHxS), and perfluoroheptanoic acid (PFHpA)—in drinking water evaluations of public water systems. Large public drinking water systems (serving more than 10,000 people) in Massachusetts have already tested for these chemicals as part of the EPA's Unregulated Chemical Monitoring Rule, and approximately three percent of the systems tested in Massachusetts had detectable concentrations of one or more PFAS compounds.
ORS set its guidance level at 70 ppt, which applies to the total summed level of all five compounds (as opposed to only the sum of two chemicals in the EPA health advisory). All five compounds have similar molecular structures and biological half-lives leading ORS to conclude that these compounds elicit similar types of effects at similar dose ranges, and thus all should be regulated similarly using an additive approach. DEP also examined what other states were doing with respect to these compounds in drinking water with Connecticut adopting the same approach as Massachusetts.
Having concluded that very low levels of the identified longer-chain PFAS compounds are a threat to drinking water in Massachusetts, the BWSC promptly issued its MCP Guidance. The MCP Guidance is based upon work conducted by ORS which led to the Drinking Water Guidance as well as the BWSC's previously published DRAFT Fact Sheet (January 2017), on which it had received comments from the LSP Association (LSPA) as well as other interested parties. As described in both the DRAFT Fact Sheet and the MCP Guidance, PFAS are considered contaminants of concern (COC) at contaminated sites regulated under M.G.L. c. 21E and the MCP because they meet the definition of “hazardous material” found in the Massachusetts statute and regulations as determined in accordance with 310 CMR 40.0342.
The MCP Guidance is the precursor to anticipated draft regulations which BWSC hopes to finalize before the end of the year. It describes how and when PFAS should be considered in connection with contaminated sites, including specifically in areas designated GW-1 where the Conceptual Site Model suggests industrial activity, waste disposal practices, or the use of aqueous film forming foam (AFFF) may have occurred. The MCP Guidance provides information concerning proper sampling techniques and analytical methods. Although the proposed Method 1 cleanup standards and Reportable Concentrations for PFAS compounds won't be known until the regulatory revisions are complete, the five identified PFAS compounds, either individually or in combination, are likely to have a Method 1 standard of 70 ppt corresponding to the drinking water standard developed by ORS. Questions remain, however, on the use of EPA analytical Method 537 (Rev.1.1)—designed to identify 14 specific PFAS analytes in drinking water—on other media, including contaminated groundwater, soil, and sediments. The MCP Guidance provides some information on this topic, but admits that further review of analytical methods available for PFAS is required. BWSC recommends close coordination and advance planning with a qualified laboratory when dealing with PFAS analysis.
In summary, potential regulatory impacts are just around the corner in Massachusetts both in the drinking water programs and with respect to cleanup of contaminated sites. To date, assessment of potentially contaminated groundwater for PFAS has followed the discovery of PFAS in public or private water supplies. With the upcoming regulatory changes to the MCP, however, many more disposal sites will be subject to increased scrutiny for these compounds. It is time to get ready!