Most of the New England states have been conducting studies to understand the levels of PFAS in wastewaters and sludges/biosolids. Most recently, Massachusetts, Connecticut and Maine have issued reports on the findings from their sampling and analysis efforts.  Here is a summary from each of those states.

PFAS in Residuals in Massachusetts
The Massachusetts Department of Environmental Protection (MassDEP) has released a report from its consultant Tetra Tech (Montpelier, Vermont) summarizing PFAS data from organic residuals with approvals for land application.  These approvals are issued through MassDEP’s Approval of Suitability (AOS) program.  AOS permit holders must test for 16 PFAS which include the 6 PFAS for which there are soil and groundwater standards in place [see Final PFAS-Related Revisions to the MCP (2019) | Mass.gov].  The report reviewed quarterly data from the third quarter 2020 through the first quarter of 2022.  Some of the key findings and conclusions included:

  • PFOS, PFOA, and PFDA were the most common of the PFAS6 found in residuals samples;

  • PFHxA and PFBA were the most common of the non-PFAS6 found in residuals samples;

  • Paper sludges contained higher percentages of long-chain carboxylic PFAS, composts had higher percentages of short-chain PFAS compounds, and PFOS was highest in other types of residuals;

  • The most common data qualifier “flag” for all PFAS compounds was the “R” flag indicating the Method Reporting Limit was above 1 ppb dry weight;

  • No “overall” trend in PFAS levels over time and no “distinct” differences by AOS type, CFR 503 designation, or Industrial Pretreatment Program status;

  • Type 1 Composts had the highest total concentrations of PFAS, with four of eleven compost facilities averaging above 50 ppb for the sum of 16 PFAS.

Tetra Tech recommended continuing the quarterly sampling program and for MassDEP to consider reducing the frequency of the duplicate sample requirements.  The MassDEP residuals testing uses modified EPA Method 533, and that will continue to be the requirement until EPA Method 1633 has been multi-lab validated. On June 23rd, the MassDEP issued revised testing guidance which reduces the Field Duplicate analyses to one to two times per year.

Additional information and data available at: Testing of PFAS in Wastewater and Residuals | Mass.gov.  The results from the required quarterly sampling can be found online, here:Energy & Environmental Affairs Data Portal (state.ma.us)

PFAS Received at Select WRRFs in Connecticut
The Connecticut Department of Energy and Environmental Protection (CTDEEP) has issued a report, “Water Pollution Control Facility PFAS Sampling Study” prepared for them by Weston & Sampson following a rigorous sampling system which looks at 35 water resource recovery facilities (WRRFs) and numerous PFAS analytes. The samples were from various media including the influent, effluent, and sludges from WRRFs, fish tissue, and surface waters upstream and downstream from 10 WRRFs. With the exception of the surface water sampling, all samples were collected in two sampling events performed in the Summer of 2021 and the Winter of 2022.

In summary, 29 of the 35 targeted PFAS analytes were present in one or more wastewater and sludge samples. The report identified eight of the most prevalent PFAS species, found in more than 50% of all samples, as PFOS, PFOA, PFBS, PFBA, PFPeA, PFHxA, PFHxS, and PFHpA. For wastewater, the most prevalent PFAS is PFPeA (a 5-carbon version of PFOA) in the influent at an average of 111 parts per trillion. In the effluent, they saw PFPeA again and PFHxA (the 6-carbon version of PFOA) was also prevalent. As with other studies, Weston & Sampson observed, in general, an increase in PFAS concentrations in the effluent. Liquid sludges were dominated by PFPeA, 6:2 FTSA, and PFHxA while the more solid sludges, or cake, were dominated by PFOS.

The 35 WRRFs were selected by CTDEEP to ensure geographic coverage and representativeness in terms of community size, as well as WRRF inputs and processes.  Several NEBRA member WRRFs were included in this study.  Analysis for PFAS was performed by Con-Test/Pace laboratories using a proprietary analytical method. Weston & Sampson also sampled and analyzed composite sludges and incinerator scrubber water at four WRRFs. The scrubber water had similar PFAS species as found in WRRF effluent but at lower concentrations.

Based on the report, the CTDEEP plans to build its database and continue with sampling, but most likely requiring WRRFs to start doing so as soon as EPA finalizes the Method 1633 for wastewater and solid medias. CTDEEP is also planning to evaluate sources of PFAS into the WRRFs. To read the full report and associated documents, go to Municipal PFAS (ct.gov).

Maine Report on PFAS Wastewater Sampling Effort
The Maine Department of Environmental Protection (MeDEP) recently released a report on wastewater effluent monitoring for PFAS that was required by legislation passed in 2021 (Public Law 2021, Chapter 641).  The monitoring was focused on the sum of six PFAS currently regulated under drinking water laws

The MeDEP report includes 3 sections with PFAS results from:

1.      Effluent/surface water discharges from WRRFs;

2.      Effluent from select Spray Irrigation facilities; and

3.      Effluent from select Industrial/Commercial WRRFs.

For a copy of the Maine report, go to:  PL2021 ch641 PFAS Sum of 6 Report- April 2023- Final-rev.3_5-30-23.pdf (maine.gov).