Per- and Polyfluoroalkyl Substances (PFAS)

Click on the topics below to expand each section.DEP Staff sampling soils for PFAS as part of the Fairfield Area PFAS investigation

Overview +  

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PFAS refer to a group of man-made chemicals known as Per- and Polyfluoroalkyl Substances. There are thousands of varieties of these chemicals including the six PFAS chemicals which are included in, Resolve 2021, Chapter 82 (Resolve, To Protect Consumers of Public Drinking Water by Establishing Maximum Contaminant Levels for Certain Substances and Contaminants) and listed below:

  • Perfluorooctanoic acid (PFOA)
  • Perfluorooctanesulfonate (PFOS)
  • Perfluorononanoic acid (PFNA)
  • Perfluorohexanesulfonic acid (PFHxS)
  • Perfluoroheptanoic acid (PFHpA)
  • Perfluorodecanoic acid (PFDA)

As early as the 1940's, PFAS (mostly PFOA and PFOS earlier on) became widely used in household products and industrial settings. These chemicals were also historically used in firefighting foams due to their effectiveness at quickly extinguishing petroleum-based fires. Because they have a unique ability to repel oil, grease, water and heat, PFAS are used in many common products that we use regularly. For example, they have been used to make non-stick cookware, stain-resistant carpets and furniture, water-resistant clothing, heat-resistant paper/cardboard food packaging (like microwave popcorn and pizza boxes), and some personal care products. PFAS break down very slowly and are persistent in the environment. This means that PFAS may build up in people, animals, and the environment over time. Health agencies are working to understand more about the health effects of low level, long-term exposure.

Potential Health Impacts from PFAS
Decreases in fertility or increases in high blood pressure in pregnant women
Reduced ability of the body’s immune system to fight infections including reduced vaccine response
Child development effects including low birth weight, accelerated puberty, bone variations, or behavioral changes
Increased risk of some cancers including prostate, kidney, and testicular cancers
Interference with the body’s natural hormones
Increased cholesterol levels and/or risk of obesity

Where is PFAS in Maine? +  

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Maine Sludge and Septage Mapper and Maine PFAS Mapper, please direct any feedback to pfas.dep@maine.gov

PFAS have been found in Maine in a number of places including: agricultural sites, drinking water supplies, surface waters, landfills, wastewater, sludge and septage spreading sites, and remediation and cleanup sites. In general, PFAS can enter the environment through direct releases from specific PFAS-containing products (e.g., certain firefighting foams), from various waste streams (sludge and septage when land applied, leachate from unlined landfills), and other pathways still being researched. In Maine, sludge and septage that may contain PFAS was applied to various “sites” for nutrient value. This activity was licensed because at the time little was known about PFAS as an emerging contaminant. 

Sludge is a solid, semi-solid, or liquid waste generated from a wastewater treatment process as well as from dewatered septage. Wastewater is used water that can include substances such as domestic, commercial, and industrial waste; food scraps; fats, oils, and grease; soaps; and chemicals and can be generated by households, businesses, and industry. Wastewater treatment systems treat this used water so that it can be recycled back into the environment. Sludge is a byproduct that has been spread for decades on agricultural land as a way to supplement farmland with nutrients.

Septage is a fluid mixture of sewage solids, liquids and sludge of domestic origin, which is collected in and removed from a septic tank system. Once a septic system is pumped out the septage must be disposed of.  Land application of septage is the most common and economical way to utilize it. Typically septage is land applied in areas that are more remote, but residential developments can be later built in those areas.

What is Maine doing about PFAS? +  

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In January 2020, the Maine PFAS Task Force released its final report and recommendations, Managing PFAS in Maine, Final Report from the Maine PFAS Task Force. This Report impacted the 130th Legislature in Maine significantly leading to new legislation and programs which are currently being implemented.

On October 18, 2021, Public Law 2021, Chapter 478, An Act To Investigate Perfluoroalkyl and Polyfluoroalkyl Substance Contamination of Land and Groundwater, became effective.
This law requires the DEP to:

  • Develop and implement a program to evaluate soil and groundwater for PFAS at locations licensed or permitted to apply sludge or septage prior to 2019.
  • Develop and implement a program for the testing of leachate (contaminated liquid that drains from a landfill) that is collected and managed by solid waste landfills for PFAS contamination.

PFAS Soil and Groundwater Evaluation of Sludge and Septage Sites

The DEP began investigating the presence of PFAS in soil and groundwater as a result of land application of sludge and/or septage in Maine communities in November 2021.

Sites to be investigated have been and continue to be identified based on decades of licensing information gathered, reviewed, and evaluated by the DEP. Each site typically includes multiple locations or “fields” and may also cross district, town, and even county boundaries. Some sites may have also been used by multiple generators meaning that sludge, septage, or both from several different sources may have been land applied at the same site.

Sludge Site Investigation

The DEP prioritized all sludge sites located around the state into four Tiers (I, II, III, IV) to designate the approximate schedule for sampling.  Tier I sites will be sampled first. Due to the large number of locations to sample,  the investigation of Tier I sites may extend through the first half of 2023. 

The Tier list will continue to be under development as sites may shift from Tier to Tier.  This is because more information is expected to be gained as the investigation continues.

Communities with Tier I Sites As of April 22, 2022: Anticipated Timeline 2021-2023

Albion*

Auburn*

Benton*

Bowdoinham*

Brooks*

Canaan

Charleston

Chelsea*

Corinna

Corinth

Dayton*

Exeter

Fairfield*

Gorham*

Gray*

Houlton*

Jackson*

Knox*

Leeds*

Littleton*

Ludlow*

Minot*

Palermo*

Presque Isle*

St. Albans

Sidney*

Skowhegan*

South Windham*

Thorndike*

Unity*

Unity Township*

Westbrook*

Winn*

* Sampling has started or is ongoing

Within each Tier the first sites will be sampled based on gaining permissions to access the sites.  Also, the DEP is working closely with the Maine Department of Agriculture, Conservation and Forestry (DACF) to identify sites that are currently being used for the production of agricultural products.

Breakdown of Tiers for the evaluation of soil and groundwater for PFAS from the land application of sludge
Tier I sites are those sites where 10,000 cubic yards or more of sludge was land applied, where homes are within 1/2 mile, and where PFAS is likely to be present in the sludge based on an evaluation of known sources or contributors of wastewater at a given treatment facility.
Tier II sites are those sites where between 5,000 and 10,000 cubic yards of sludge were land applied, where homes are within 1/2 mile, and where PFAS is likely to be present in the sludge based on an evaluation of known sources or contributors of wastewater at a given treatment facility. In cases where homes are over 1/2 mile away, a site may be downgraded to Tier III depending on distance and other hydrogeological factors.  Likewise, a site may be elevated to Tier I if results from a Tier II site with similar source contributions show a greater than anticipated impact to the soil and water being tested. 
Tier III sites are those sites where under 5,000 cubic yards of sludge were land applied, where homes are within 1/2 mile, and where PFAS is likely to be present in the sludge based on an evaluation of known sources or contributors of wastewater at a given treatment facility. Likewise, a site may be elevated to Tier I or II if results from a Tier III site with similar source contributions show a greater than anticipated impact to the soil and water being tested. 
Tier IV sites are those sites where information gathered to date indicates that no sludge was land applied. Additional research and time will be needed to verify this information. Once identified, these sites may be placed in another Tier as appropriate using the above criteria.

As part of this investigation, both soils and groundwater will be sampled in an effort to determine where PFAS is located in Maine’s environment and its proximity to drinking water in private groundwater wells. Where it is determined that private wells exceed Maine’s interim drinking water standard for the sum of 6 PFAS (PFOA, PFOS, PFNA, PFHxS, PFHpA, and PFDA), and contamination is likely due to the land application of sludge, DEP will work with homeowners to ensure that they have clean water to drink.

NEW: Preliminary Private Drinking Water Well Information by Town as of June 1, 2022

DEP will provide homeowners that are included as part of this investigation with bottled water until a filtration system is installed and deemed effective. Once installed, the system will be sampled a month after installation to ensure that it is still working correctly. If it is established that the filtration system is working effectively, bottled water will no longer be provided, and instead a schedule will be developed for the monitoring and maintenance of the installed filtration system.

Inquiries about the Soil and Water Evaluation should be directed to David Madore, Deputy Commissioner and Communications Director, David.Madore@maine.gov, 207-287-5842. You can also contact the Department directly by e-mail at: pfas.dep@maine.gov

Septage Site Investigation

The land application of septage will be investigated separately from sludge. This is because septage is licensed and managed differently than sludge. Investigation of these sites will begin statewide by May 2022.

Initial investigations into the land application of septage will begin in the communities identified in the table below. Additional counties and towns will be added as more contracts are put into place.

County Communities Who is doing the work
Aroostook Benedicta, Blaine, Cary Plt, Castle Hill, Cross Lake Twp, Crystal, Dyer Brook, Eagle Lake, Easton, Fort Fairfield, Frenchville, Grand Isle, Haynesville, Houlton, Island Falls, Monticello, Nashville Plt, New Canada, Presque Isle, St. Agatha, St. John, Sherman, Stockholm, TD R2, T16 R9, Wallagrass, Washburn DEP staff
Penobscot Patten, Stacyville
Washington Danforth
Cumberland Baldwin, Bridgton, Casco, Gorham, Gray, Harrison, Naples, Raymond Campbell Environmental Group
Oxford Andover, Bethel, Brownfield, Fryeburg, Lovell
York Parsonsfield
Androscoggin Livermore Falls

Haley Ward

Kennebec Albion, Belgrade, Canaan, Chelsea, Readfield, Vassalboro, West Gardiner, Windsor
Sagadahoc Bowdoinham, Phippsburg
Knox North Haven, Owl's Head, Thomaston, Union, Warren, Washington Fessenden Geotechnical (FGT) and John Turner Consulting (JTC)
Lincoln Bristol, Damariscotta, Newcastle, Nobleboro, Squirrel Island, Westport Island, Wiscasset
Waldo Belfast, Frankfort, Freedom, Islesboro, Palermo, Searsmont, Swanville

Similar to the sludge investigation as described above, where it is determined that private wells exceed Maine’s interim drinking water standard for the sum of 6 PFAS (PFOA, PFOS, PFNA, PFHxS, PFHpA, and PFDA), and contamination is likely due to the land application of septage, DEP will work with homeowners to ensure that they have clean water to drink.

Inquiries should be directed to David Madore, Deputy Commissioner and Communications Director, David.Madore@maine.gov, 207-287-5842. You can also contact the Department directly by e-mail at: pfas.dep@maine.gov

PFAS Landfill Leachate Testing

On September 1, 2021, the Department sent a letter to solid waste landfills that manage leachate (contaminated liquid that drains from a landfill) requiring that leachate be tested for PFAS, beginning October 18, 2021, as required by Public Law 2021, Chapter 478. Five rounds of sampling are required in total: each round collected during the fall and spring beginning fall 2021 and ending fall 2023. Data collected must be sent to the Department for review and evaluation. In 2024 DEP will present this data to the legislature along with recommendations.

NEW: Fall/Winter 2021 Landfill Leachate Sampling Results for 6 PFAS (PFOA, PFOS, PFNA, PFxHS, PFHpA, and PFDA)

PFAS Investigation at Remediation Sites in Maine

PFAS contamination is also being investigated at remediation sites in Maine. Investigation of PFAS at remediation sites typically occurs to assess whether a hazardous substance is present at a concentration that poses a threat to public health or the environment. In these cases, the DEP works toward remediating or mitigating those identified threats.

The Maine legislature changed the definition of hazardous substance under the state’s uncontrolled sites law in 2021 to include PFAS.  Public Law 2021, Chapter 117, An Act Regarding Uncontrolled Hazardous Substance Sites, clarifies that a hazardous substance means any substance that is defined as a hazardous substance or a pollutant or contaminant under the United States Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). At this time, PFAS is managed as a pollutant or contaminant under CERCLA as PFAS is not yet designated as a CERCLA hazardous substance.

Specific remediation programs at DEP that have investigated PFAS contaminated sites include the Uncontrolled Sites Program, Municipal Landfill Closure and Remediation, VRAP, and Brownfields programs.  In addition several Federal facilities and Superfund sites are also undergoing investigation and remediation of PFAS. 

PFAS in Products

Common questions regarding Maine’s law addressing products containing intentionally added PFAS.

What is EPA doing about PFAS? +  

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In May 2016 the federal Environmental Protection Agency (EPA) issued a drinking water Health Advisory for PFOA and PFOS. If these chemicals are measured in drinking water above 70 nanograms per liter, also known at 70 parts per trillion, the EPA recommends taking action to reduce exposure. Maine had been following this standard until June 21, 2021 when the legislature adopted a lower interim drinking water standard in, Resolve 2021, Chapter 82, Resolve, To Protect Consumers of Public Drinking Water by Establishing Maximum Contaminant Levels for Certain Substances and Contaminants.

On April 27, 2021, EPA Administrator Michael Regan established an EPA Council on PFAS to understand and reduce the risks associated with PFAS.  On October 18, 2021, as a result of recommendations from the Council, the EPA released its PFAS Strategic Roadmap. The roadmap sets timelines between 2021 and 2024 by which EPA plans to take specific actions and commit to new policies in the interest of protecting public health and the environment.

Data and Guidance +  

Updates and Timeline +  

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Fairfield-Area PFAS Investigation

March 15, 2022 - PFAS presentation to the Maine Grocers and Food Producer’s Association

January 30, 2022 - PFAS presentation to the Joint Standing Committee on the Environment and Natural Resources

January 14, 2022 - PFAS presentation at Maine Agricultural Trades Show

October 20, 2021 - PFAS Briefing to the Board of Environmental Protection

February 8, 2021 - PFAS Briefing for the Committee on Environment and Natural Resources (off-site video, briefing begins at approximately 47:50)

February 1, 2021 - Letter to EPA 

November 12, 2020 - Maine sludge and bioash spreading information (Excel), please note the file contains links that will not work. Please direct any feedback to pfas.dep@maine.gov

January 2020 - Managing PFAS in Maine, Final Report from the Maine PFAS Task Force

August 14, 2019 - Emergency Sludge Dewatering State Wastewater Infrastructure Planning and Construction Grants Available

June 10, 2019 -letters from the Northeast Committee on the Environment to US Committee on Environment and Public Works and Congressional PFAS Task Force.

March 22, 2019 - The Department notified sludge/biosolids program licensees and related composting facilities of a new requirement to test for PFOA, PFOS, and PFBS. Upcoming deadlines include submission of an updated Sampling and Analytical Work Plan by April 12, 2019, and initial sampling to be conducted by May 7, 2019.

March 22, 2019 - DEP Announces Testing of All Sludge Materials Before Land Application

March 6, 2019 - Governor Mills Signs Executive Order Establishing Task Force Charged with Studying Effects of PFAS Prevalence in Maine

More Information +  

Contact Us

General inquiries regarding PFAS should be directed to David Madore, Deputy Commissioner and Communications Director, David.Madore@maine.gov, 207-287-5842. You can also contact the Department directly by e-mail at: pfas.dep@maine.gov