U.S. EPA released the first set of data collected by public water systems (PWS) pursuant to the Fifth Unregulated Contaminant Monitoring Rule (UCMR 5). UCMR 5 required PWS serving more than 10,000 customers to sample for 29 specific per- and polyfluoroalkyl substances (PFAS), including perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), and hexafluoropropylene oxide dimer acid (GenX). The key take-aways from this newly released data (which represents about seven percent of the data that U.S. EPA expects to receive from the UCMR 5 sampling) are as follows:

  • PFOA and PFOS were identified above their minimum reporting levels (above 4 ppt) in 8.5% and 7.8% of the PWS, respectively;
  • GenX was found in only one PWS (representing 0.5% of the PWS) above its health advisory level;
  • Detectible concentrations of nine other PFAS were identified above their minimum reporting levels (U.S. EPA has not set health advisory levels for these nine PFAS); and
  • Sixteen PFAS were not detected above their respective minimum reporting levels.

With respect to PFOA and PFOS, because U.S. EPA's controversial health advisory levels for these compounds are set below the minimum reporting levels, any detectible concentration of PFOA and PFOS is by definition in excess of its health advisory level.

In the press release that accompanied the data drop, U.S. EPA's Assistant Administrator for Water, Radhika Fox stated "PFAS are an urgent public health issue facing people and communities across the nation. The latest science is clear: exposure to certain PFAS, also known as forever chemicals, over long periods of time is linked to significant health risks. That's why the Biden-Harris Administration is leading a whole-of-government approach to address these harmful chemicals. As part of this commitment, EPA is conducting the most comprehensive monitoring effort for PFAS ever, at every large and midsize public water system in America, and at hundreds small water systems."

We will continue to monitor subsequent UCMR 5 data releases at the Corporate Environmental Lawyer blog.

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