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

What is PFAS? +  

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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 influenced Maine’s 130th Legislature to establish new legislative initiatives related to PFAS. Below are some of the new PFAS laws currently undergoing implementation.

Maine's 130th Legislature (2021-2022)

Resolve, To Protect Consumers of Public Drinking Water by Establishing Maximum Contaminant Levels for Certain Substances and Contaminants
(Maine’s interim drinking water standard for PFAS)

Resolve 2021, Chapter 82
An Act To Investigate Perfluoroalkyl and Polyfluoroalkyl Substance Contamination of Land and Groundwater
(PFAS soil and groundwater evaluation)
Public Law 2021, Chapter 478
An Act To Prevent the Further Contamination of the Soils and Waters of the State with So-called Forever Chemicals
(PFAS sludge and sludge products ban)
Public Law 2021, Chapter 641
An Act Regarding the Statute of Limitations for Injuries or Harm Resulting from Perfluoroalkyl and Polyfluoroalkyl Substances
(Statute of limitations for injuries or harm from PFAS)
14 MRS §752-F
An Act Regarding Uncontrolled Hazardous Substance Sites
(Revision of definition of uncontrolled substances to allow for PFAS)
38 MRS §1362 (1)(H)
Resolve, To Address Perfluoroalkyl and Polyfluoroalkyl Substances Pollution at State-owned Solid Waste Landfills
(Study PFAS management at state-owned landfills)
Resolve 2021, Chapter 172
An Act To Restrict the Use of Perfluoroalkyl and Polyfluoroalkyl Substances in Firefighting Foam
(Restrictions in firefighting or fire suppressing foam)

38 MRS 424-C

An Act To Protect the Environment and Public Health by Further Reducing Toxic Chemicals in Packaging
(PFAS in Food Packaging)
32 MRS §1733 (3-B)
An Act To Stop Perfluoroalkyl and Polyfluoroalkyl Substances Pollution
(Regulation of PFAS in products)
38 MRS §1614
PFAS Soil and Groundwater Evaluation of Sludge and Septage Sites

DEP Staff sampling soils for PFASPublic Law 2021, Chapter 478, An Act To Investigate PFAS Substance Contamination of Land and Groundwater became effective on October 18, 2021. This law requires the DEP to develop and implement a program to evaluate soil and groundwater for PFAS at locations licensed to land apply sludge or septage prior to 2019.

DEP began its initial statewide evaluation into the presence of PFAS in soil and groundwater at licensed sludge/septage land application sites in November 2021. Sites were identified based on gathering, reviewing, and evaluating decades of licensing information. Each site typically includes multiple fields (i.e., agricultural land, pasture, or other land) and may also cross district, town, and county boundaries. Some sites may have different owners than when a license was first issued, requiring DEP’s evaluation to include identifying land use changes and practices. As an example, a site that was an active farm back in 1986 may now include several small farms, a subdivision, and a school. Moreover, some sites may have been used by multiple generators (different sources of sludge or septage), which land applied in the same location.

The initial evaluation process for each site includes sampling of soils at licensed land application sites as well as nearby private drinking water wells (groundwater) determined to be at risk for PFAS impacts from these sites. Initial evaluation sampling locations are developed by DEP scientists based on several site-specific factors including land application records, hydrogeology, and proximity to licensed sites.

Once DEP staff have completed the initial evaluation, DEP scientists review the data and make a determination as to whether an expanded investigation is necessary, referred to as a “step-out investigation”. Where groundwater levels exceed Maine’s interim drinking water standard surrounding a land application site, the radius of investigation may be expanded. Not all sites will require step-out sampling. Step-out sampling may take a few extra weeks or in some cases may take years for larger sites that have many fields contributing to potential contamination.

DEP Staff sampling water after treatment In locations where it is determined that private drinking water 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 or septage, DEP will work with homeowners to ensure that they have clean water to drink. In these circumstances, DEP will provide homeowners with bottled water until a filtration system can be installed and determined to be effective.

Preliminary Private Drinking Water Well Information by Town as of September 1, 2022

To ensure that the system is effective, DEP will sample the system 1-3 months after installation. If the 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.

At active farms, sampling of PFAS in agricultural products, irrigation water, and at specific soil locations is coordinated through the Maine Department of Agriculture, Conservation and Forestry as the needs for farmers are different than other types of landowners and homeowners.

Evaluation of Licensed Sludge Sites
In October 2021, DEP prioritized all licensed sludge sites statewide into four Tiers (I, II, III, IV) to designate an approximate schedule for sampling. Initial sampling evaluations are currently being conducted at Tier I sites first. Tiers II, III, and IV will follow.
Breakdown of Tiers for the evaluation of soil and groundwater for PFAS from the land application of sludge
Tier I 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 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 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 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.

Communities with Tier I and II Sites

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 August 9, 2022: Anticipated Timeline 2021-2022

Albion

Auburn

Benton

Bowdoinham

Brooks

Canaan

Charleston

Chelsea

China

Corinna

Corinth

Dayton

Exeter

Fairfield

Fort Fairfield

Freedom

Gorham

Gray

Hodgton Holden Houlton Jackson Knox Leeds

Littleton

Ludlow

Minot

New Limerick

Oakland

Palermo

Presque Isle

St. Albans

Sidney

Skowhegan

South Windham

Thorndike

Unity

Unity Township

Westbrook

Winn

 
 
Communities with Tier II Sites - Initial evaluation to begin August 2022
Auburn Bald Mountain Township Bowdoin College Grant West Brassua Township Caratunk Charleston Chase Stream Township
Dayton Durham Frankfort Freedom Fryeburg Gorham Gray
Greenville Hartford Haynestown Plantation Hebron Hobbstown Township Knox Leeds
Lewiston Long Pond Township Machias Mayfield Minot New Gloucester North Yarmouth
Pierce Pond Township Pleasant Ridge Plantation Raytown Township Richmond Saco Sandwich Academy Grant Sangerville
Skowhegan Turner T1R13WELS West Gardiner West Middlesex Grant Township Whitefield  

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

Evaluation of Licensed Septage Sites

Septage land application sites are being evaluated separately than sludge. This is because septage application sites are licensed and managed differently than sludge, and several are currently active. Evaluation of these sites began Summer 2022.

Initial investigations into the septage land application sites began in the communities identified in the table below. Additional counties and towns will be added as more contracts are put into place. Similar to the sludge site investigation, the initial evaluation process for each site includes sampling of soils at septage land application sites, as well as nearby private drinking water wells (groundwater) for PFAS.

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

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

Status of Investigation of Licensed Sludge and Septage Sites

DEP expects to complete the initial evaluation of Tier I sites and begin initial evaluations of Tier II sites in August 2022. This means that DEP will be able to shift the focus to the evaluation of Tier II sites while simultaneously conducting step-out sampling in Tier I sites, as warranted, as well as continued filtration system monitoring.

Status of Initial Sludge Evaluation at Tier I Sites by Municipality as of October 1, 2022 (Individual site locations may cross municipal boundaries)
Initial evaluation complete (step-out investigation complete or not required) Step-out investigation required Initial evaluation expected to be complete December 2022 (step-out to be determined)

Albion
Auburn *
Benton
Bowdoinham
Brooks
Chelsea
Dayton/Biddeford *
Fort Fairfield
Freedom
Gorham *
Gray
Holden
Houlton
Hodgdon
Jackson
Knox *
Leeds *
Littleton
Ludlow
Minot *
New Limerick
Oakland
Palermo/China
Sidney
Skowhegan
South Windham
St. Albans
Thorndike
Westbrook
Winn

Canaan
Fairfield

Corinth/Exeter/Charleston *
Corinna/Newport
Unity

* In these communities Tier 1 initial investigation is complete but there are also Tier 2 sites in that same community.

This shift forward does not mean that the DEP will never return to a Tier I location. It just means the initial evaluation is complete. In some Tier I locations, the DEP will continue to sample when a step-out investigation is needed.

Evaluation of septage sites began during the summer of 2022. As of early August sampling has begun in some but not all communities identified under Evaluation of Licensed Septage Sites. Additional information will be provided soon.

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.

Landfill Leachate Sampling Results for 6 PFAS (PFOA, PFOS, PFNA, PFHxS, PFHpA, and PFDA):

Fall/Winter 2021

Spring/Summer 2022

Fall/Winter 2022: Data not available yet

Spring/Summer 2023: Data not available yet

Fall/Winter 2023: Data not available yet

PFAS Investigation at Remediation Sites in Maine

PFAS contamination is also being investigated at remediation (or cleanup) sites in Maine. Investigation of PFAS at these sites typically occurs to assess whether a hazardous substance is present at a concentration that poses a risk to public health or the environment. In these cases, the DEP works toward removing 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 under 38 MRS §1362 (1)(H). This change clarifies that a hazardous substance means any substance that is listed as a hazardous substance or meets the criteria for 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 compounds are not yet designated as a CERCLA hazardous substance. This may change as the EPA implements it’s 2021 PFAS Strategic Roadmap.

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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On April 27, 2021, the federal Environmental Protection Agency (EPA) Administrator Michael Regan established an EPA Council on PFAS to understand and address the risks associated with PFAS. Up until this time, EPA’s guidance for drinking water was based upon a Health Advisory (HA) for PFOA and PFOS published in May of 2016. The 2016 drinking water HA stated that when PFOA or PFOS, or both combined, were found to be above 70 nanograms per liter (or 70 ppt), actions should be taken to reduce exposure. Maine had been following this standard until June 21, 2021 when the Maine legislature adopted an 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 October 18, 2021, as a result of recommendations from the EPA Council on PFAS, the EPA released a PFAS Strategic Roadmap. The roadmap set forth 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. These actions are not limited to drinking water but include a wide variety of other environmental programs.

The EPA announced new PFAS HAs for drinking water on June 15, 2022. It is important to note that an HA is not legally binding or enforceable but may be used as a mechanism for guidance and decision-making. The interim and final HAs are depicted in the table below.

PFAS Compound New Health Advisory
PFOA 0.004 ppt (Interim)*
PFOS 0.02 ppt (Interim)*
GenX Chemicals 10 ppt (Final)
PFBS 2,000 ppt (Final)
* An Interim Health Advisory means that the advisory is still draft and must undergo Science Advisory Board (SAB) approval. For PFOA and PFOS the interim advisory falls below current laboratory reporting levels. This means that current laboratory methods can’t determine whether or not PFOA or PFOS would be present or reliably determine how much is present.

EPA anticipates it will release a draft Maximum Contaminant Level (MCL) for PFOA and PFOS in drinking water by the end of 2022. An MCL is an enforceable legal standard that identifies the highest level of a contaminant that is allowed, while considering best available technology and costs. Maine DEP will continue to review the use of Maine’s legally enforceable interim drinking water standard as it relates to the HAs and the development of Maine’s and the draft national MCLs.

How can PFAS be removed from the environment? +  

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Technology for the treatment, concentration, and destruction of PFAS is still in its early stages and at this time there is no universal, cost effective way to remove PFAS from all media. Furthermore, technologies currently available to manage PFAS vary based upon the type of media. For example, removing PFAS in water requires different considerations and processes than removing PFAS from soil, sludges, leachate, vegetables, milk, beef, or other contaminated media. This is because each media type has unique characteristics which may pose challenges with existing technology. Both the USEPA and the State of Maine are researching new technologies and methods for treating, concentrating, and destroying PFAS. It is anticipated that options will be evolving rapidly over the next several years.

Treating PFAS in Drinking Water

PFAS treatmentAt this time, there are several widely recognized and effective technologies for the removal of PFAS from water. The most common techniques include adsorption (the adhesion of atoms, ions, or molecules from a gas, liquid, or dissolved solid to a surface) using media such as Granular Activated Carbon (GAC) and Ion Exchange (IX), or Reverse Osmosis (RO). Information about each of these technologies is available at the USEPA website. In addition, the USEPA has more information about novel technologies for PFAS treatment through its Drinking Water Treatability Database.

Maine residents with private drinking water wells exceeding Maine’s interim drinking water standard, as identified through the state’s soil and groundwater investigation, are provided with filtration systems to ensure their drinking water is clean and safe. Typically, Maine DEP and its consultants install GAC systems, but in some circumstances an Ion Exchange or Reverse Osmosis system may be determined to be more economical and is utilized. GAC is an effective method of treatment in the vast majority of cases and has been shown to be effective through ongoing post-installation sampling at Maine residences.

One consideration of treating PFAS in drinking water is that filters collect PFAS resulting in residuals or waste materials with concentrated levels of PFAS. These residuals or waste materials must be properly disposed of or destroyed.

USEPA’s Research Regarding PFAS Treatment and Destruction

In 2019, the USEPA issued a Technical Brief on the incineration of PFAS as a means to manage waste streams. This technical brief outlined the state of the science in 2019 and did not clearly endorse incineration as a safe or preferred method for managing PFAS waste streams. This is because some research has indicated that PFAS may break down into components that may be other forms of problem PFAS chains. In April 2022, the Pentagon halted the practice of incineration at Department of Defense sites.

In Spring 2020, the USEPA established the PFAS Innovative Treatment Team (PITT), a team of interdisciplinary staff, to evaluate options for PFAS treatment and destruction. More detail about their work is available at the above USEPA website specifically pertaining to these four technology types: super critical water oxidation (SCWO), pyrolysis and gasification, mechanochemical degradation, and electrochemical oxidation.

In August 2020, the USEPA Office of Innovation issued a PFAS Challenge to the nation for innovative ways to destroy PFAS. Applicants were asked to develop destruction technologies to achieve 99% destruction of PFAS in Aqueous Film Forming Foam (AFFF) formulations (i.e., fire suppressant foam). Winners of the challenge submitted proposals for the following technologies: Hydrothermal processing, UV light, and continuous flow liquid-phase plasma discharge.

Later the same year, USEPA’s Office of Research and Development (ORD) presented information to Region 1 States and Tribes on PFAS Treatment and Destruction Technologies, and at the end of the year released the Interim Guidance on the Destruction and Disposal of Perfluoroalkyl and Polyfluoroalkyl Substances and Materials Containing Perfluoroalkyl and Polyfluoroalkyl Substances. The document provided information on state of science and associated uncertainties for current commercially available disposal or destruction technologies (as of late 2020).

In June 2022, USEPA established a PFAS Thermal Treatment Database with information about the following methods of thermal treatment for PFAS:

Type of Thermal Treatment

Description of Treatment

Calcination

A type of incineration performed on solid materials.

Pyrolysis

A process that decomposes materials at moderately elevated temperatures in an oxygen-free environment with the goal of producing a material for beneficial reuse (e.g., biochar, syngas).

Gasification

A process similar to pyrolysis that uses uses small quantities of oxygen, using heat from the partial combustion process to provide heat for gasification.

Granular activated carbon reactivation

A process that passes PFAS contaminated water through granular active carbon, or GAC to which PFAS compounds adhere. The GAC can then be thermally reactivated, removing the adsorbed contaminants and allowing the GAC to be recycled and reused.

Hydrothermal processing

A process which uses high-temperature and high-pressure water to degrade PFAS compounds.

Incineration

A process which uses high temperature and oxygen to degrade PFAS compounds.

Indirect thermal desorption

A process which removes PFAS from contaminated media through indirect heat without combustion.

Smoldering

A process which uses a slow, flameless form of combustion to degrade PFAS.

The state of science is still evolving and is expected to change over the next several years as more and more entities develop and engineer new methods for treatment and destruction. At this time however, most of the existing technologies are in pilot phase only and have not been developed for larger scale use. This means that traditional disposal methods, such as landfilling, continue to be the current mechanism for PFAS management.

State of Maine Research and Collaboration Regarding PFAS Treatment and Destruction

Multiple State agencies including Maine’s DEP, Department of Agriculture, Conservation and Forestry (DACF), and Department of Inland Fisheries and Wildlife (DIF&W), are working together to monitor and evaluate opportunities to use new technologies for treatment, concentration, and destruction of PFAS. This includes addressing concerns about sludge, septage, leachate, water, soil, milk, animal wastes, and other agricultural products. Because technologies are still evolving, matching the right technology to the right location and set of circumstances, while also ensuring that funding is available to support these new technologies, is challenging. Maine is struggling to find readily available technologies that will resolve issues surrounding statewide treatment and destruction needs quickly and within reasonable costs. At this time, the above state agencies are coordinating efforts to research and identify technologies suitable for treating multiple waste streams as identified below.

PFAS Waste Stream

Possible Treatment Technologies

Sludges (including septage)

Anson Madison Sanitary District (AMSD) is working with ECT2, the State of Maine, and with support from some of Maine’s Congressional Delegation to develop a regional treatment center for PFAS in sludges or liquids. This upgraded facility would be a place for the region to take waste sludges, manure wastes, and other semi-liquid wastes for PFAS treatment. The technology would be placed at the back end of the normal wastewater treatment process as a final “finishing” of water to ensure that water discharged is treated for PFAS. One of the challenges is the overall cost necessary to achieve near-zero levels of PFAS in treated effluent.

The Maine legislature banned the land application of sludge through LD 1911, effective August 8, 2022. As a result of this ban, wastewater treatment facilities that generate sludge are looking into large scale drying centers for sludge so that sludge waste products contain less moisture. This enables easier transport of the waste for landfilling and also allows landfill operators to more easily accommodate the waste streams. The challenge to this technology is that the cost for setting up such a facility may be prohibitive, and funding is a concern.

Milk

In early 2021, Maine DEP and DACF recognized that milk was going to become a priority waste stream for farmers who learned their dairy herds were producing PFAS-contaminated milk. Volumes of waste milk vary based on the size of the farm, but the amounts could be significant and may contribute to further contamination.

In 2021, Brown and Caldwell, produced a Technical Memorandum for Maine DEP outlining various options for managing PFAS-impacted milk and dairy wastes (i.e., manure and process water). Also, in 2021, Maine DEP contracted with ACV Environmental to conduct a pilot project for treating PFAS-impacted milk and dairy wastes from a dairy farm in Fairfield. This pilot project informed the state that milk waste is a complex media based on its elevated fat content (versus water), and that typical water filtration systems would not be effective without consideration of significant design challenges.

In early 2022, Maine DEP and DACF began coordinating to find a system that might be designed specifically for treating PFAS-impacted milk. The basic idea would be to concentrate the PFAS and dispose of that concentrated amount, which would allow the bulk of the liquid to be disposed normally without risk of PFAS contamination. Currently, the state is researching options for a centralized or regional milk disposal system and a portable milk treatment system. This effort is in early stages of research and design.

Beef and animal wastes (carcasses)

In the Spring of 2022, Maine DEP and DIF&W began a pilot study on the composting of animal carcasses (turkeys, as a result of contaminated wildlife. Waste Management Disposal Services of Maine (WMDSM) provided a location and equipment to conduct the pilot study. The purpose of the study is to not only reduce the volume of PFAS-impacted animal wastes but also find out if the composting process can effectively reduce PFAS concentrations in order to see if compost can be made available for alternative uses (e.g., perhaps alternative daily cover for landfills). The state plans to conduct another compost study with deer later this year.

Soils

The Aroostook Band of the Micmac Nation, Upland Grassroots, Connecticut Agricultural Experiment Station are looking at phytoremediation using hemp to see if hemp plant uptake of PFAS would effectively reduce levels of PFAS in the soil. Other researchers have been in communication with DEP and the University of Maine looking at phytoremediation using vegetation that acts as a hyper-accumulator other than hemp as a means to reduce PFAS levels in the soil. One of the challenges to phytoremediation is that once PFAS is removed from the soil, the plants will have concentrated levels of PFAS that must then be appropriately disposed of or destroyed.

Landfill leachate

The 130th legislature through LD 1875 requires the Bureau of General Services (BGS) to report to the legislature in 2023 on treatment options for PFAS in landfill leachate at two state owned landfills - the Juniper Ridge Landfill in Old Town, and the Dolby Landfill in East Millinocket. The BGS has contracted with Sevee and Maher Engineers to conduct the study, which is currently underway.

Data and Guidance +  

Updates and Timeline +  

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Fairfield-Area PFAS Investigation

August 4, 2022 - Maine Property Tax School

June 16, 2022 - NEWMOA Board Meeting

April 1, 2022 - Maine Water Environment Association Spring Conference

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