New Massachusetts PFAS Drinking Water Standard

Per- and polyfluoroalkyl substances (PFAS) are a family of chemicals used since the 1950s to manufacture stain-resistant, water-resistant, and non-stick products. Additionally, certain types of firefighting foams historically used by the U.S. military, local fire departments, and airports to fight oil and gasoline fires may contain PFAS. PFAS are of concern because they stay in the environment for a long time and do not break down easily. Since 2013, numerous public water supplies throughout Massachusetts have detected PFAS concentrations exceeding the United States Environmental Protection Agency’s reporting limits. Based on this, in January 2019, the Massachusetts Department of Environmental Protection (MassDEP) announced that it would begin the process of developing a Maximum Concentration Limit (MCL) for drinking water for PFAS. This process culminated when MassDEP released its updated Massachusetts Drinking Water Regulations 310 CMR 22.00, which was published and went into effect on October 2, 2020.

Under Section 22.07G, the PFAS6 MCL is established as 20 nanograms per liter (ng/l), or 0.000020 parts per million/0.02 parts per billion. PFAS6 is defined as the sum of the concentrations of the following six contaminants: Perfluorooctane Sulfonic Acid (PFOS), Perfluorooctanoic Acid (PFOA), Perfluorohexane Sulfonic Acid (PFHxS), Perfluorononanoic Acid (PFNA), Perfluoroheptanoic Acid (PFHpA) and Perfluorodecanoic Acid (PFDA). Section 22.07G(3)(e) directs MassDEP to review relevant developments in the science, assessment and regulation of PFAS in drinking water every three years to evaluate whether to amend the PFAS MCL. Based on this evaluation, the PFAS MCL could be changed and additional compounds could be added to the list of regulated contaminants in the future.

Section 22.07G further outlines the monitoring and reporting requirements, which are required for “Every Supplier of Water operating a Community Water System or Non-transient, Non-community Water System“ (with the exception of suppliers of Transient Non-Community Water Systems, which are required to collect and report one sample per sampling point by September 30, 2022). For all remaining water suppliers, 22.07G(4) specifies the sample locations required based on the number of water entry points for the water system and 22.07G(5) establishes the initial sampling frequency of four consecutive quarterly samples for each sample location, which is to be analyzed for PFAS6. Each sample is to be collected the first month of every quarter during the initial monitoring period. The initial monitoring period is to commence as follows:

  • For a supplier of a population of greater than 50,000 individuals – January 1, 2021
  • For a supplier of a population of 50,000 individuals or fewer, but greater than 10,000 individuals – April 1, 2021
  • For a supplier of a population of 10,000 or fewer individuals – October 1, 2021

Following the completion of the initial monitoring period, a routine monitoring protocol can be established based on the analytical data.

Note that if you are a public water supplier, MassDEP is offering FREE testing for PFAS: for more information, refer to: ,

If you need assistance in evaluating if and how this new requirement applies to you, please contact ,Dawn Horter, PG, LSP for additional information.