PFAS Treatment Details by State

The information presented below was collected in 2024 by ASDWA as part of a state survey on reviewing and approving PFAS treatment techniques/technologies. The survey respondents were state engineering managers, review engineers, and drinking water program administrators with knowledge of engineering approval practices for PFAS. The information is presented in three tables: PFAS Treatment Approvals by State, Review Criteria by State, and Links to Guidance, Documentation, or SOPs.

NOTE: this is a work in progress. ASDWA is sharing these draft tables to allow community access to this information while we work to compile additional information and continually refine the display of the information so it’s easier to use. In the near future, we will provide online forms that states can use to submit additional information. In the meantime, please share any additions or corrections directly with ASDWA via email or the Engineering Community Team site.

We hope states will find this and future resources helpful in their work, and we ask that the community provide feedback for enhancement, questions, comments, or concerns to Anthony DeRosa of ASDWA at aderosa(at)asdwa.org.

PFAS Approvals by State

wdt_ID State Approved PFAS Treatment - Groundwater Approved PFAS Treatment - Surface Water Approved PFAS Treatment - GW and SW Treatment Type(s) Other Mitigation
1 PA Yes No No GAC and IX
2 WI Yes No No GAC and IX
3 NH Yes No No GAC, PFAS Resin, POU Resin, POU RO
4 KS Yes No No GAC
5 MP Yes No No GAC and RO
6 AZ Yes No No GAC and IX There is one system that has RO installed to treat for arsenic and nitrate and later it was discovered that they also have PFAS so they incidentally treat for PFAS as well.
7 WI Yes No No RO, GAC, IX
8 MA Yes Yes Yes GAC, IX, and RO
9 AK Yes No No GAC There is one system that is using Nano membranes successfully to remove PFAS, but that was a side benefit of the treatment system which was and approved originally for other treatment objectives. There are two proposals for an Ion Exchange system that was
10 ME Yes No No GAC - connection changes Two systems abandoned their well. Other systems are currently working toward connection to a nearby clean PWS.
State Approved PFAS Treatment - Groundwater Approved PFAS Treatment - Surface Water Approved PFAS Treatment - GW and SW Treatment Type(s) Other Mitigation

State Testing Requirements

wdt_ID State Granular Activated Carbon (GAC) Reactivated Granular Activated Carbon (GAC) Ion Exchange (IX) Reactivated Ion Exchange (IX) Membranes New Media New Treatment Technique
1 PA Arsenic testing if it is bituminous coal based. Pilot testing is required of GAC on surface water systems. Piloting for SW. NSF Pilot testing NSF Piloting Pilot testing Piloting
2 WI Pilot test or Rapid Small Scale Column Pilot testing Pilot testing
3 NH Larger systems generally conduct a voluntary pilot evaluation for media capacity and pretreatment needs NSF/ANSI 61 No NSF if regen offsite. If onsite, then no retesting other than pH neutralization and continued monitoring of contaminant removals. NSF NSF NSF + pilot or demonstrated success elsewhere
4 KS Requirements would not differ between GW or SW. NSF/ANSI certification required. Need pilot testing to demonstrate treatment will be effective. Also require a wastestream summary review to identify how process waste will be disposed of. Pilot testing Pilot testing Pilot testing + literature from independent source demonstrating efficacy. Examples from other states would be requested. Pilot testing + literature from independent source demonstrating efficacy. Examples from other states would be requested.
5 MP Haven't required any testing to date. But we have required manufactures certification of treatment. We haven't authorized reactivated GAC to date. We are trying to not use any reactivated GAC unless produced on island. We worked with EPA ORD and haven't allowed Ion exchange to date due to the high levels of salt water intrusion already. No testing but NSF certification for actual membranes. Pending levels we do require quarterly or annual monitoring at EP. Same requirements.
6 AZ ADEQ may require some type of tests to support vendor estimates and at the very least will require extensive source water characterization. Pilot testing is preferred but may not be mandatory for all projects, and decisions will be made on a case by case basis. NSF The process is anticipated to be similar to GAC for single pass ion exchange. The regeneration of ion exchange will not be recommended, but probably not prohibited (for example, if a system has PFAS and nitrate, they will have to regenerate). Membrane performance testing requirements will be minimal (since performance is constant and better controlled than with GAC or AIX). Testing shall cover source characterization (including seasonality impact), vendor’s estimates for system specific water quality parameters (WQPs) based on challenge testing, characterization of waste streams and waste management in line with PFAS regulation, as well as corrosion control (that has to include inventory, WQPs screening for at least one year before installation, desktop analysis and additional testing in line with predictions, and eventually mitigation strategy). This will not be recommended because in accordance with EPA recommendations, ADEQ would like to see mature (well-established technology/media) to be applied for PFAS. Since PFAS has to be treated to almost non detect, using new media that brings new operation uncertainties will be challenging. However, this option will not be prohibited, and testing will require piloting until breakthrough, together with training staff for operation and exploring limits. Testing goals for groundwater and surface water are the same, even though the surface water will require more testing to analyze and address variabilities. This will not be recommended because in accordance with EPA recommendations, ADEQ would like to see mature (well-established technology/media) to be applied for PFAS. However, this option will not be prohibited, and testing will require more mass balance and byproduct transformation analysis.
7 WI The department has initially required pilot testing except in limited application and situations where the use of rapid small scale column testing has been permitted. RSSCT in lieu of pilot studies have been considered and approved for systems to install emergency treatment for PFAS. Data collected from the emergency treatment systems may be used to satisfy certain pilot study requirements. NSF - Limited pilot applications have been performed with reactivated GAC, but the expectations and requirements would be the same. For surface water systems, the duration of the pilot testing may be required to be a year due to the variability in surface water quality over the course of the year. This expectation would be evaluated on a case-by-case basis depending on the potential variability in the source water quality and whether this treatment would be utilized for other contaminants. The department has initially required pilot testing except in limited application and situations where the use of rapid small scale column testing and modeling has been permitted. RSSCT in lieu of pilot studies have been considered and approved for systems to install emergency treatment for PFAS. Data collected from the emergency treatment systems may be used to satisfy certain pilot study requirements. For regenerated ion exchange medias, the expectation would likely be two treatment cycles depending on the life of the media. No proposals for regenerative ion exchange media for PFAS removal have been proposed at this time. For surface water systems, the duration of the pilot testing may be required to be a year due to the variability in surface water quality over the course of the year. This expectation would be evaluated on a case-by-case basis depending on the potential variability in the source water quality and whether this treatment would be utilized for other contaminants. The department would require a minimum of 2 months of pilot testing data for membrane installations to align with the membrane filtration guidance manual but may prescribe longer depending on the potential for variability in source water quality. In limited cases the department may consider the use of computer modeling with other full scale installations to shorten the duration of pilot testing. For surface water systems, the duration of the pilot testing may be required to be a year due to the variability in surface water quality over the course of the year. This expectation would be evaluated on a case-by-case basis depending on the potential variability in the source water quality and whether this treatment would be utilized for other contaminants. New proprietary medias would likely be required to complete at a minimum a single pilot filter run to breakthrough to verify the efficacy of the media with the systems water quality. Depending on the media and results of the initial run a second run may be required to verify and confirm conclusions. For surface water systems, the duration of the pilot testing may be required to be a year due to the variability in surface water quality over the course of the year. This expectation would be evaluated on a case-by-case basis depending on the potential variability in the source water quality and whether this treatment would be utilized for other contaminants. New proprietary medias would likely be required to complete at a minimum a single pilot filter run to breakthrough to verify the efficacy of the media with the systems water quality. Depending on the media and results of the initial run a second run may be required to verify and confirm conclusions. For surface water systems, the duration of the pilot testing may be required to be a year due to the variability in surface water quality over the course of the year. This expectation would be evaluated on a case-by-case basis depending on the potential variability in the source water quality and whether this treatment would be utilized for other contaminants.
8 MA MassDEP requires that a pilot study be conducted for two seasons ( Winter & Summer). Alternatively, we accept RSSCT with pre-qualifying conditions to demonstrate "equality”. • We currently do not have any users of Reactivated GAC, but we do have a policy on Reactivated GAC that would equally apply. • The requirements for GW and SW are the same For Single Pass IX, a minimum of 10 days of piloting is required, according to our current policy. • For regenerated IX, bench scale piloting may be required or in some cases we allow full-scale, on -line, demonstrations studies with monthly monitoring. • New Proprietary Adsorptive Media, with NSF approval, would be subject to off-line pilot testing/bench testing; or RSSCT piloting. • A minimum of 10 days of piloting is required. • The requirements for GW are the same as SW. • A new treatment technique (e.g., PFAS destruction technology) would require testing by a reputable, third-party organization, such as ANSI/NSF 61 to ensure that the products of such a technology does, in any way, add residual, alternative forms of PFAS to the drinking water or any other product of health concern. It is expected that testing would be conducted by Mass Spec. analyses or similar analytical techniques for further assurance. • The end point is when MassDEP is assured that the finish water to the consumer is free of any detrimental effects. • The requirements for GW would be the same as SW.
9 AK We would require/recommend initial pilot testing or bench testing (pilot test preferred) to demonstrate the selected GAC will work well for that PWS water quality. If time is of an essence and such testing cannot be conducted before the treatment has to be installed, then we may consider a literature review of analogous GAC systems used for similar water characteristics. There will also be an Interim Approval to Operate period (usually 1 yr) where we would require that full-scale performance data be collected to verify the treatment system performs as intended in the design. If there are any shortcomings, the design team may need to make O&M adjustments, or other more involved adjustments to the design (e.g. add more GAC treatment vessels to increase EBCT, or switch to different GAC media, etc.). The latter two would require prior review/approval from the State before changes are implemented. NSF-61 would be required. Bench or pilot testing showing bed volumes to breakthrough and recommended regeneration frequency for the full scale design. May also ask for them to characterize the regeneration effluent for PFAS levels to coordinate with our Wastewater permitting division and ensure they will have a disposal option that could be approved/permitted for such effluent. No different approach for GW vs. SW We would require initial pilot testing or bench testing (pilot test preferred) to demonstrate the selected membrane will work well for that PWS water quality. We would recommend the end-point to be at least past one clean-in-place cycle; but may be beneficial if they could extend longer to get better idea on fouling /cleaning effects on performance. I say recommend since PFAS is not a formally regulated DW contaminant in the state since a primary MCL has not been established by the EPA. Thus, it becomes harder to establish pre-design stipulations on our approvals. So length and effort in pre-design pilot and bench testing would depend on the PWS owner and design firm stipulations. There will also be an Interim Approval to Operate period (usually 1 yr) where we would require that full-scale performance data be collected to verify the treatment system performs as intended in the original design. No difference for GW or SW systems as it relates to PFAS. There would be differences if the membrane is also used as a primary microbial barrier for meeting the SWTR (e.g. would need to see third party validation of membrane for microbial removal effectiveness). We are not familiar with such technology. But would likely approach similar to GAC, IX, Membranes. Woudl want some assurance from prior testing that the technology has a high likelihood of removing PFAS at the levels found in the source water and with the Water quality characteristics found locally. May want to look at redundancy concept in the design, energy/power requirements and power quality needs for reliable operation. We would also ask about waste stream management (liquid or air-based wastes) to ensure that project could have a path for approval to dispose of such waste streams (i.e. will it be viable).
10 ME we do not require pilot testing as a general practice. I am unaware of any pilot testing occurring at any PWS with PFAS over Maine State standards.
State Granular Activated Carbon (GAC) Reactivated Granular Activated Carbon (GAC) Ion Exchange (IX) Reactivated Ion Exchange (IX) Membranes New Media New Treatment Technique

SOPs and Guidance by State

wdt_ID State SOP or Guide for Treatment Approval SOP Link/Details
1 PA
2 WI We have requirements for pilot studies for new treatment under NR 811.44
3 NH Yes
4 KS We follow minimum design standards and EPA guidance/regulations.
5 MP
6 AZ Draft ADEQ does not have SOPs for reviewing treatment and probably will not make one since treatment review is project specific. We are, however, working on guidance documents for PWSs and engineering firms to support permitting (describing what must be submitt
7 WI The department has some publicly available information regarding pilot testing requirements which would be applicable for the review and approval of treatment. There is not however an SOP for the actual review process.
8 MA MassDEP approval guidance is as follows: Websites:  Drinking Water Permits, Forms, and Templates | Mass.gov  https://www.mass.gov/doc/drinking-water-policy-90-04-pilot-study-requirements-for-proposed-treatment/download?_ga=2.178082789.1590996434.1702650
9 AK No specific guidance. We do have checklists for engineering plan reviews that we direct applicants to use when preparing a submittal for our review/approval. They can be found here: https://dec.alaska.gov/eh/dw/engineering/plan-review-checklist/
10 ME
State SOP or Guide for Treatment Approval SOP Link/Details