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Per- and Polyfluoroalkyl Substances (PFAS)


June 26, 2020 Public Notice

The Public Notice provided to all Postal Patrons in Acton on June 26, 2020 is a required notice by the Massachusetts Department of Environmental Protection (MassDEP).  We understand it may have been dense, confusing, and unexpected.  The document may be summarized in a series of major take away messages.

  • The Acton Water District (AWD) proactively sampled for PFAS based on the presence of two Superfund Sites in Acton and the push towards further regulation of PFAS at the State and Federal level.  Based on the results of initial testing, all production wells and treatment plants serving our system were sampled for PFAS.
  • PFAS exposure can occur from drinking water and many other sources in the home and some work places.
  • Currently two of our five water treatment plants have tested above the MassDEP Guideline and proposed drinking water regulatory limit of 20 parts per trillion (ppt) for six PFAS compounds.
  • MassDEP is currently focused on the sum of six, out of thousands of PFAS compounds believed to exist.  The six compounds include Perfluorooctane sulfonic acid (PFOS), and Perfluorooctanoic acid (PFOA), Perfluorononanoic acid (PFNA), Perfluorohexanesulfonic acid (PFHxS), Perfluoroheptanoic acid (PFHpA),and Perfluorodecanoic acid (PFDA).
  • If you are in the sensitive subgroup, including pregnant women, nursing mothers, and infants, MassDEP advises not to consume water with greater than 20 ppt of the six PFAS substances of concern.  Using bottled water that has been tested as PFAS free is recommended for the sensitive subgroup to use for drinking, cooking foods that absorb water, and preparing infant formula. 
  • PFAS as a chemical class are still considered an emerging contaminant and the ability to reliably test for PFAS in the ppt range is relatively new and challenging.  Data takes time to be generated and interpreted.  PFAS is also the first time we as a public water supplier have been tracking a contaminant at the ppt level.  Typically, we work with contaminants in the part per million (ppm) and part per billion (ppb) concentrations.
  • We are in the early stages of addressing PFAS and will provide updates as new information is available.  Please sign up for email updates by sending an email with your name address, and email address to with “Updates” in the subject line.
  • The treatment facility with the highest concentration of PFAS is not currently serving water to the system pending further investigation.


According to the United States Environmental Protection Agency, PFAS are a group of man-made chemicals that includes PFOA, PFOS, GenX, and many other chemicals. PFAS have been manufactured and used in a variety of industries around the globe, including in the United States since the 1940s. PFOA and PFOS have been the most extensively produced and studied of these chemicals. Both chemicals are very persistent in the environment and in the human body – meaning they don’t break down and they can accumulate over time. There is evidence that exposure to PFAS can lead to adverse human health effects.

PFAS can be found in:

  • Food packaged in PFAS-containing materials, processed with equipment that used PFAS, or grown in PFAS-contaminated soil or water.
  • Commercial household products, including stain- and water-repellent fabrics, nonstick products (e.g., Teflon), polishes, waxes, paints, cleaning products, and fire-fighting foams (a major source of groundwater contamination at airports and military bases where firefighting training occurs).
  • Workplace, including production facilities or industries (e.g., chrome plating, electronics manufacturing or oil recovery) that use PFAS.
  • Drinking water, typically localized and associated with a specific facility (e.g., manufacturer, landfill, wastewater treatment plant, firefighter training facility).
  • Living organisms, including fish, animals and humans, where PFAS have the ability to build up and persist over time.

Certain PFAS chemicals are no longer manufactured in the United States as a result of phase outs including the PFOA Stewardship Program in which eight major chemical manufacturers agreed to eliminate the use of PFOA and PFOA-related chemicals in their products and as emissions from their facilities. Although PFOA and PFOS are no longer manufactured in the United States, they are still produced internationally and can be imported into the United States in consumer goods such as carpet, leather and apparel, textiles, paper and packaging, coatings, rubber and plastics.

Current Data

June 22, 2020 Data Table

The most recent data representing water that has gone through our treatment plants is summarized here.  These numbers may be subject to change if quality control review or compliance calculations change.

Part per trillion

In order to understand what a chemical measurement means, one needs to have a basic understanding of the type of measuring units used, and what they mean. As mentioned above, most of our contaminants are measured using concentration units such as ppm and ppb.  But what is a ppm, ppb, or ppt for that matter, in plain English?

As an example, lets use an example of liquid chlorine added to our water in the treatment process at 1.0 ppm. This value refers to one part of chemical (in this case liquid chlorine) found in one million parts of our water. To realize how small a value this actually is, read the analogies listed below:

One part per million (ppm) equals:

      • 1 inch in 16 miles

One part per billion (ppb) equals:

      • 1 inch in 16,000 miles

One part per trillion (ppt) equals:

      • 1 inch in 16 million miles (600+ times around the earth)

How can I stay informed?

If you do not typically receive a water bill from the Acton Water District and wish to receive future updates regarding PFAS, please visit this website periodically or send an email to with “Updates” in the subject line.  Please include your name, address, and email to be informed of new information and future developments related to PFAS.

What if i am not supplied water by AWD?

In consultation with MassDEP, our initial Public Notice regarding PFAS is being sent to every Postal Patron in Acton.  This includes many people who do not receive water from our sources of supply but may have an interest in knowing that PFAS is present in the community.  If you have questions regarding PFAS in your primary water supply, you may wish to contact one of the following water systems that may serve recipients of our Public Notice.  Contact phone numbers listed are from publicly available records and may not be current.

Concord Water Division 978-318-3250

Littleton Water Department 978-540-2222

Pine Hill Condominium 978-264-0166

Strawberry Hill Apartments 781-894-3952

Acton Indoor Tennis/Nashoba Sportsman’s Club 978-263-9059

Planet Gymnastics/All Seasons Tennis 978-263-1900

Private Well Resources

In the spring of 2020, the Acton Board of Health mailed a fact sheet regarding PFAS to owners of private wells that they had contact information for.  If you did not receive this information, it can be found here:  Additional resources and information will likely be available for private well owners throughout Massachusetts in the future.  You may contact the Acton Health Department at 978-929-6632 for additional information on private wells.

Archive of status updates

As new updates are provided, the previous information will be available here organized by date.


USEPA PFAS Resources:

MassDEP PFAS Resources for Public Water Supplies:

MassDEP PFAS Regulatory Process:

MassDEP Bottled Water PFAS Results: