Unregulated Contaminant Monitoring Report Data Released by EPA
This month, the U.S. Environmental Protection Agency (EPA) released the initial results of its Unregulated Contaminant Monitoring Rule No. 5 (UCMR-5), which required testing starting in January of 2023 of drinking water sources for 29 per- and polyfluoroalkyl substances (PFAS) as well as lithium. According to the results from the Public Water Suppliers (PWS), 8.5% of the systems exceeded EPA’s reference concentration for PFOS, 7.8% exceeded the reference concentration for PFOA, and 22.1% exceeded EPA’s reference dose for lithium. This initial release of data represents only one of the 12 quarterly monitoring results required by UCMR-5 through December 2025. EPA will continue to receive this quarterly data through 2026.
The Safe Drinking Water Act requires monitoring every five years for priority contaminants not yet regulated in drinking water. This is how the PFAS contamination at farms in Maine were initially discovered. UCMR-5 results will be used to support development of future drinking water regulations. A summary of the data can be found here: Data Summary of The Fifth Unregulated Contaminant Monitoring Rule | US EPA. Future results to be posted here: National Contaminant Occurrence Database (NCOD) | US EPA
4th Draft Method 1633 for PFAS Released
In July, the EPA’s Office of Water, Engineering and Analysis Division, working in collaboration with the Department of Defense, issued the 4th Draft Method 1633 Analysis of Per- and Polyfluoroalkyl Substances (PFAS) in Aqueous, Solid, Biosolids, and Tissue Samples by LC-MS/MS (epa.gov). The fourth draft of Method 1633, which involves liquid chromatography-mass spectrometry (x2), is still only for aqueous solutions but does include wastewaters.
The 74-page document includes multi-lab-validated results for this testing methodology. Method 1633 is still a long way from formal promulgation through federal rulemaking, where it would be approved for compliance testing purposes. However, EPA is stating that there is unlikely to be any major changes to the method and is therefore recommending use of the method for testing PFAS in aqueous matrices. Some National Pollutant Discharge Elimination System permits being issued in Massachusetts and other non-delegated states are including the requirement.
EPA anticipates the final version of Method 1633 for solid matrices and landfill leachate will be out later this year. See EPA’s main page for Clean Water Act analytical methods for PFAS for more information on this topic: CWA Analytical Methods for Per- and Polyfluorinated Alkyl Substances (PFAS) | US EPA
National Collaborative PFAS Study Update
The national study being led by Dr. Ian Pepper, Director of The Water & Energy Sustainable Technology (WEST) Center at the University of Arizona, titled “Evaluation of Fate and Transport of PFAS Following Long-Term Land Application of Biosolids: A Collaborative National Study” is moving along now. For more detailed information on this project, including the background, objectives and methodology, see National PFAS Research Study — NEBRA (nebiosolids.org). There is also an hour-long recorded presentation by Dr. Pepper all about this project when it was being launched last year: https://youtu.be/zy5A5Jg8GXk.
To date, 22 sites have been identified to be part of the study including one in New Hampshire and one in Maine. The soil sampling started last Fall and they are about half-way through the sites. This is not an easy project – especially when weather and other factors cause delays.
Initial results from this study are showing PFAS in soils at the sites to be in the low parts per billion range for the majority of samples. Once sampling and analysis is completed, the researchers will move on to the modeling phase of the study. They expect to have all sampling completed by the end of 2023. Modeling should be done by the end of 2024.
Saint-Gobain Leaving Merrimack NH and PFAS Legacy Behind
NEBRAMail has written about the struggles of the Town of Merrimack, New Hampshire, one of the earliest examples of a major PFAS contamination in the region (Four years of PFAS challenge at Merrimack NH — NEBRA (nebiosolids.org)). Merrimack began composting its biosolids in 1982. Its finished compost product has been a consistent quality, nicely screened, and in-demand commodity. As with other biosolids-based soil amendments, PFAS concerns are causing disruptions and issues in the getting these products to end markets. Now, the company responsible for Merrimack’s PFAS contamination, Saint-Gobain, is planning to move out. See Saint-Gobain announces closure of Merrimack facility | New Hampshire Public Radio (nhpr.org) for more on this story.