Montana Department of Environmental Quality About Us Permitting & Operator Assistance Public Participation


Program Overview

Per and Polyfluoroalkyl Substances

Per- and polyfluoroalkyl substances (PFAS) are a group of man-made chemicals that includes PFOA, PFOS, 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 Contacts


To sign up for email updates related to PFAS.


36% of Montana’s population served by public water supplies drink from systems tested during 2013-2015 under the Unregulated Contaminant Monitoring Regulation (UCMR3). All systems tested below the method reporting limit (MRL).

More information can be found at:

MT0000235 City of Hardin HARDIN
MT0004313 Pipkin Commercial Subdivision BELGRADE
MT0004392 Cherry Creek Manuf. Home Park BILLINGS
MT0000328 City of Shelby SHELBY
MT0000590 Leisure Village MHP HLNA HELENA
MT0000165 Town of Bridger BRIDGER
MT0000155 County Water District of Billings Heights BILLINGS
MT0000161 City of Bozeman BOZEMAN
MT0000170 Butte Silverbow Water Department BUTTE
MT0000241 Helena Water System HELENA
MT0000259 Kalispell Public Worksn KALISPELL
MT0004204 University of Montana - Missoula MISSOULA
MT0000294 Mountain Water Company MISSOULA
MT0000525 City of Great Falls GREAT FALLS
MT0000153 City of Billings BILLINGS
Contaminants Tested (UCMR3) MRL μg/L
PFOS - Perfluorooctanesulfonic acid 0.04
PFOA – Perfluorooctanoic acid 0.02
PFNA- Perfluorononanoic acid 0.02
PFHxS- Perfluorohexanesulfonic acid 0.03
PFHpA- Perfluoroheptanoic acid 0.01
PFBS- Perfluorobutanesulfonic acid 0.09

Disposal of PFAS and PFAS-containing materials is informed by EPA’s interim guidance released in 2020. Be sure to consult with any landfill before attempting to deliver bulk PFAS materials to them or contact DEQ for specific guidance.

  • Contaminated media – Incineration or landfill. Incineration would likely take place outside of Montana and may need to be coordinated by a hazardous waste transporter service (see list). Not all landfills will accept PFAS-contaminated soils or wastewater residuals. Be sure to contact the landfill directly before hauling to them.
  • Consumer products – PFAS-containing consumer products can be disposed of like any other Group II waste; therefore, they may be disposed of at any licensed Class II landfill. Items like mattresses and carpets may be managed separately. Class II landfills typically have liners which collect leachate and allow chemicals like PFAS to be managed.
  • Bulk PFAS (like leftover Aqueous Fire Fighting Foam)
    • Disposal of solidified material in a lined unit at a licensed Class II landfill. Verify with the landfill first. Not all landfills will accept given the uncertainties.
    • Contracting with a hazardous waste transporter service. Though not a characteristic hazardous waste, AFFF is being transported by some of these companies to facilities that accept it. A transporter might manage the PFAS in one of the following ways:
      1. Delivering to an incinerator in another state for thermal destruction.
      2. Delivering to a hazardous waste landfill or storage facility until more research on disposal technologies is conducted.
      3. Deep well injection.
      4. Solidifying the material and landfill at a licensed Class II landfill.

What are PFAS?

PFAS, sometime referred to as forever chemicals, is an acronym for per- and polyfluoroalkyl substances. PFAS are a group of thousands of manufactured chemicals that have been used in industry and consumer products since the 1940s because of their useful properties. One common characteristic of concern of PFAS is that many break down very slowly and can build up in people, animals, and the environment over time.

EPA: Our Current Understanding of the Human Health and Environmental Risks of PFAS

What are PFOA and PFOS?

PFOA and PFOS are acronyms for the chemicals “perfluorooctanoic acid and perfluorooctane sulfonic acid,” respectively. PFOA and PFOS are two of the most widely used and studied PFAS.

How can I be exposed to PFAS?

Humans are exposed to per- and polyfluoroalkyl substances (PFAS) through a wide variety of pathways, and most people in the U.S. have detectable amounts of one or more specific PFAS in their blood. The most common sources of human exposure to PFAS include:

  • Drinking water, especially in areas where the water source is near where PFAS have been used or disposed such as landfills and airfields.
  • Surfaces treated with PFAS-containing stain and waterproofing protectants such as carpets, furniture, or clothing. PFAS are ingested through the mouth or from breathing in dust.
  • Foods that may contain PFAS when they come from areas with contamination include fish, game meat, dairy products, and produce.
  • Food that is packaged in materials that contain PFAS such as fast-food wrappers or microwave popcorn bags.
  • Industrial exposure to workers and firefighters who make or use PFAS containing products.

What kinds of products contain PFAS?                                    

Some common products that may contain per- and polyfluoroalkyl substances (PFAS) include, but are not limited to, the following:

  • grease-resistant paper, fast food containers/wrappers, microwave popcorn bags, pizza boxes, and candy wrappers;
  • stain resistant coatings used on carpets, upholstery, and other fabrics;
  • water resistant clothing;
  • cleaning products (such as some laundry detergents and stain removers);
  • personal care products (shampoo, dental floss) and cosmetics (nail polish, eye makeup); and
  • paints, varnishes, and sealants).

We are learning more all the time about products that may contain PFAS. 

ATSDR: How Can I be Exposed?

EPA: Our Current Understanding of the Human Health and Environmental Risks of PFAS

What are the health risks associated with PFAS?

Only a few of the thousands of per- and polyfluoroalkyl substances (PFAS) have been studied for their potential to affect people’s health. Research is ongoing and we will learn more over time. Studies in groups of people suggest that exposure to certain PFAS may lead to health problems including increased cholesterol levels, changes in the liver, decreased infant birth weights, decreased vaccine response in children, increased risk of high blood pressure during pregnancy, and increased risk of kidney and testicular cancers.

ATSDR: What are the health effects of PFAS? 

What steps are the US EPA taking to address PFAS?

The study of per- and polyfluoroalkyl substances (PFAS) is still developing. In October 2021, EPA announced the Agency’s PFAS Strategic Roadmap: EPA’s Commitments to Action 2021-2024. The Roadmap includes EPA’s approach, goals, and objectives.  

PFAS Strategic Roadmap: EPA's Commitments to Action 2021-2024

Has EPA developed any PFAS drinking water health advisories?

In 2016, EPA adopted a lifetime drinking water health advisory of 70 nanograms/liter (ng/L) or parts per trillion (ppt) for perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS).  When both PFOA and PFOS are found in drinking water, the combined concentrations of PFOA and PFOS should be compared against the 70 ppt health advisory.

EPA: PFOA & PFOS Drinking water Health Advisories

In June 2022, EPA released new drinking water health advisories for four per- and polyfluoroalkyl substances (PFAS): PFOA, PFOS, GenX chemicals (a PFOA replacement), and perfluorobutane sulfonic acid (PFBS; a PFOS replacement).  EPA set interim health advisories for PFOA and PFOS at 0.004 ng/L (ppt) and 0.02 ng/L (ppt), respectively, both of which are significantly lower than the 2016 lifetime drinking water health advisory levels (see above). EPA also established final health advisories for GenX chemicals and PFBS at 10 ng/L (ppt) and 2,000 ng/L (ppt), respectively.

According to EPA, health advisories provide information that may be used to protect people from negative human health effects resulting from exposure to contaminants that are known or anticipated to occur in drinking water. These updated drinking water health advisories are non-enforceable and non-regulatory and will be in place until Maximum Contaminant Levels (MCLs) are set for drinking water.

EPA: Drinking Water Health Advisories for PFAS Fact Sheet for Communities

Has EPA developed any PFAS drinking water standards?

EPA is developing a proposed National Drinking Water Regulation under the Safe Drinking Water Act for perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). As EPA undertakes this action, the agency is also evaluating additional per- and polyfluoroalkyl substances (PFAS) and considering regulatory actions to address groups of PFAS.  The new rule will establish an enforceable standard, or Maximum Contaminant Level (MCL). A MCL is the highest level of a contaminant allowed in public drinking water based on cost benefit analysis.  

Are any PFAS listed as hazardous substances under the federal Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), also known as Superfund?

Not currently, however, in late-2022 EPA proposed to designate two per- and polyfluoroalkyl substances (PFAS), perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), as hazardous substances under CERCLA. EPA anticipates finalizing the designation in Summer 2023. Once designated, PFOA and PFOS would be further analyzed under Superfund law.

As of early 2023, PFAS are not regulated under the federal Resource Conservation and Recovery Action (RCRA).

EPA: Per- and Polyfluoroalkyl Substances (PFAS) Proposed PFAS National Primary Drinking Water Regulation

EPA: Proposed Designation of Perfluorooctanoic Acid (PFOA) and Perfluorooctanesulfonic Acid (PFOS) as CERCLA Hazardous Substances

What is Montana DEQ doing with respect to PFAS?

In 2019, DEQ initiated a PFAS Working Group with other Montana state and local government agencies to provide a coordinated response to the many per- and polyfluoroalkyl substances (PFAS) challenges.  In June 2020, the PFAS Working Group adopted the Montana PFAS Action Plan.

DEQ identified known and potential PFAS sources/sites that include the locations where PFAS may have been stored, used, disposed, or otherwise released to the environment. Potential PFAS sites include, but are not limited to, industrial sites, dumps or landfills, wastewater treatment plants, biosolids application sites, and fire training areas or airplane crash sites where aqueous film forming foam (AFFF) was used for fire suppression.

DEQ is gathering information on potential PFAS impacts in Montana through sampling of public water supplies, groundwater, surface water, sediments, and fish tissue.

For more information on DEQ’s sampling activities, please see PFAS Surface and Groundwater Monitoring

DEQ is providing on-going regulatory oversight for identified PFAS sites in Montana, including Department of Defense sites. For more information on these sites, please see PFAS Sites of Concern.   

Has the State of Montana developed any PFAS standards?

In 2019, the Montana Department of Environmental Quality (DEQ) added perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) to Circular DEQ-7 Montana Numeric Water Quality Standards for groundwater at the 2016 EPA Health Advisory level of 70 ng/L (ppt).

DEQ also has the ability to use broad surface water standards to protect state surface waters from substances attributable to municipal, industrial, agricultural practices or other discharges that will create concentrations or combinations of materials which are toxic or harmful to human, animal, plant, or aquatic life and create conditions which produce undesirable aquatic life.

Circular DEQ-7 Montana Numeric Water Quality Standards

Administrative Rules of Montana

Has my public water system been sampled for PFAS?

Possibly, between 2013 and 2015, EPA sampled medium-size Montana public water systems as part of the Third Unregulated Contaminant Monitoring Rule (UCMR3). This sampling effort was part of a nationwide look at the potential for PFAS in public drinking water systems.  Samples were analyzed for six PFAS compounds: perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorohexane sulfonic acid (PFHxS), perfluoroheptanoic acid (PFHpA), and perfluorobutane sulfonic acid (PFBS). No detections were found above the laboratory reporting limit for these six PFAS compounds. Some of the public water systems sampled include Billings, Bozeman, Butte, Helena, Kalispell, Hardin, Belgrade, Shelby, and Bridger.  For information on EPA’s monitoring between 2013 and 2015, please see the UCMR 3 Occurrence Data.

Under the new Fifth Unregulated Contaminant Monitoring Rule (UCRM5), additional Montana public water systems will be monitoring for 29 PFAS.  Sample collection will begin in January 2023 and conclude in December 2025.

Should I test my private water supply well for PFAS?

If you feel that your private water supply well has the potential to be impacted by per- and polyfluoroalkyl substances (PFAS), please contact DEQ’s drinking water program (see staff contacts on our PFAS webpage) to discuss PFAS sampling protocol. Special care needs to be taken during PFAS sampling to ensure collection of representative water samples. An environmental professional can also assist with collection of these water samples.

What are the best current treatment technologies to reduce PFAS in private drinking water?

Viable per- and polyfluoroalkyl substances (PFAS) water treatment options include activated carbon treatment, ion exchange treatment, or high-pressure membranes.

Public drinking water systems must contact DEQ prior to using PFAS treatment.

EPA: Reducing PFAS in Drinking Water with Treatment Technologies

Where can I find more information on PFAS?

Please see below links for more per- and polyfluoroalkyl substances (PFAS) information

Agency for Toxic Substances and Disease Registry (ATSDR):

The Environmental Council of the States (ECOS):

Interstate Technology Regulatory Council (ITRC):

Montana Environmental Health Assessment and Education Program:

United States Air Force FAQs (July 2019):

US Environmental Protection Agency (EPA): Questions and Answers: Drinking Water Health Advisories for PFOA, PFOS, GenX Chemicals and PFBS | US EPA

US Environmental Protection Agency (EPA): Steps you can take to reduce your risk: Meaningful and Achievable Steps You Can Take to Reduce Your Risk | US EPA

US Food and Drug Administration:
Hi, I can help answer your questions!