What are PFAS?
Per- and polyfluoroalkyl substances (PFAS) are a broad class of synthetic chemicals used to make products that resist heat, oils, grease, stains, and water. PFAS chemicals can be found in Teflon coated cookware, carpets, clothing, paper packaging for food, fire retardants, and aqueous film-forming foam (AFFF). Because these chemicals are so stable, they are slow to decompose; as a result, they will remain in soil, air, surface water, groundwater, wastewater plant effluent, sewage sludge, and landfills “forever”.
EPA’s Maximum Contaminant Levels (MCLs) for PFAS:
In April, the EPA finalized a National Primary Drinking Water Regulation (NPDWR) that established maximum contaminant levels (MCLs) for six PFAS in drinking water. EPA also finalized health-based, non-enforceable Maximum Contaminant Level Goals (MCLGs) for these PFAS. The key difference between MCLs and MCLGs is that MCLs are enforceable limits.
Note: PFAS mixtures containing at least two or more of PFHxS, PFNA, HFPO-DA, and PFBS use a Hazard Index MCL to account for the combined and co-occurring levels of these PFAS in drinking water.
Under the final rule, effective June 25, 2024, drinking water systems must initiate a monitoring program for PFAS (2024-2027) and water systems must initiate compliance monitoring (2027-2029), and take action to reduce the levels of these PFAS in drinking water. Starting in 2029, drinking water systems must comply with the MCLs and report any exceedances.
California Public Health Goals:
On April 5, 2024, the California Environmental Protection Agency’s Office of Environmental Health Hazard Assessment (OEHHA) adopted public health goals (PHGs) for perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) in drinking water. A PHG is the level of a drinking water contaminant that does not pose a significant risk to health with lifetime exposure from all uses of tap water. The final public health goal for PFOA is 0.007 parts per trillion (ppt), and 1 ppt for PFOS, reflecting the best current science on their cancer-causing potency. California will have up to two years to adopt regulations that are no less stringent than the federal PFAS MCLS.
Drinking water analytical methods include EPA Method 537.1 (tests 18 PFAS compounds) and EPA Method 533 (tests 25 PFAS compounds). Both of these methods include PFOA, PFOS, GenX, PFBS, PFNA, and PFHxS.
Potential PFAS Impacts on Stormwater and Wastewater Dischargers
To meet MCL requirements in surface waters that supply drinking water systems, facilities that discharge stormwater or wastewater may be required by their oversight agencies to address PFAS, this may be done in one of the following ways:
Investigate PFAS sources onsite including contamination or PFAS introduction as a part of the manufacturing process;
Source control and phase out/substitute PFAS materials;
Perform internal PFAS monitoring and sampling adhering to strict protocols to avoid contamination;
Implement best management practices (BMP) to ensure PFAS is not introduced into manufacturing process;
Keep in mind that PFAS is detected in the natural background and in rainwater samples;
The San Francisco, CA Municipal Regional Stormwater Permit has begun requiring PFAS monitoring. Other jurisdictions may request PFAS sampling or the development of PFAS monitoring plans.
PFAS Treatment:
The current best available treatment technologies to remove PFAS from drinking water include granular activated carbon, ion exchange, and reverse osmosis treatment systems. Given the challenges associated with PFAS treatment including generation of PFAS waste, we recommend first considering source control measures.
ALG has being tracking national PFAS regulations and assisting clients to prepare for and comply with PFAS-related requirements. We understand the chemistry and can help interpret SDS’ to determine which chemicals are PFAS versus which are other fluorinated molecules. If you would like to learn more about how we can help you assess PFAS compliance, please contact Mia Hill (mhill@algcorp.com), Christine Wong (cwong@algcorp.com), or Elliott Ripley (eripley@algcorp.com)