On December 18, 2020, the Environmental Protection Agency (EPA) issued its Interim Guidance on the Destruction and Disposal of Perfluoroalkyl and Polyfluoroalkyl Substances [PFAS] and Materials Containing Perfluoroalkyl and Polyfluoroalkyl Substances (Interim Guidance), as directed under the National Defense Authorization Act for Fiscal Year 2020 (NDAA FY2020).
| Guidance on Six Material Types |
| 1. Solid, liquid or gas waste streams |
| 2. Aqueous film-forming foam (AFFF) |
| 3. Soils & biosolids |
| 4. Textiles |
| 5. Spent water treatment materials |
| 6. Landfill leachate |
The Interim Guidance identifies six (6) material types – 1) solid, liquid, or gas waste streams from facilities that manufacture or use PFAS, 2) aqueous film-forming foam (AFFF), 3) soils & biosolids, 4) textiles, 5) spent water treatment materials (activated carbon, ion exchange resins, high pressure membranes), and 6) landfill leachate – in which the EPA describes technologies that may be used for destruction or disposal of associated PFAS. The Interim Guidance does not provide a specific recommendation on what technologies to utilize but rather lays out the additional research that is needed before concrete guidance can be provided. In addition, the Interim Guidance does not establish PFAS concentrations that would necessitate destruction or disposal for these six (6) material types. The Interim Guidance does, however, provide insight into the different existing technologies and techniques currently being explored for destruction or disposal of PFAS.
The EPA tentatively recommends four (4) different approaches as summarized below in order of uncertainty (lowest to highest) for disposal of PFAS:
- Held in or placed in interim storage – Although the Interim Guidance does not detail the specifics for storage, it does note the use of best management practices for storage. This approach does not destroy the PFAS and thus, other options may become more important as more information is obtained.
- Injection into deep wells – There are a limited number of deep wells currently able to receive liquid-phase PFAS, and location, waste transportation, and associated costs may significantly limit practicability.
- Disposal in Resource Conservation and Recovery Act (RCRA) Subtitle C permitted hazardous waste landfills – These sites are already known to have the “most stringent environmental controls” for hazardous waste management.
- Placed in solid waste landfills – If sites have composite liners and leachate collection treatment systems.
Two other potential options that are being considered having greater uncertainty than those listed above are hazardous waste combustors and other thermal treatment devices. These units, which include hazardous waste incinerators (HWIs), cement kilns, lightweight aggregate kilns (LWAKs), boilers, carbon reactivation units, sewage sludge incinerators, municipal waste combustors, thermal oxidizers, and hydrogen chloride (HCl) production furnaces that burn hazardous waste, typically achieve 99.99% destruction for non-PFAS air pollutants. It is expected that all of these sources would be subject to Clean Air Act (CAA) permitting requirements which may include air emission limitations, source testing, and/or recordkeeping requirements. However, the uncertainty these units have for destruction of PFAS is due to concerns about the products of incomplete combustion (PICs) and release of non-PFAS pollution (such as other combustion pollutants). The Interim Guidance does not provide detail as to which PICs are of greatest concern or what to do about them, nor does it address the risks associated with PIC air emissions. However, the EPA is actively working to conduct research and gather information to conclude whether PICs are adequately controlled.
Overall, the EPA’s Interim Guidance document concluded that more research is needed to reach recommendations on method of destruction to use, what the PICs are, and how to mitigate them. EPA’s Interim Guidance will be updated every three years as required under the NDAA FY2020. In addition, EPA is actively exploring other novel disposal technologies beyond the established approaches discussed in the Interim Guidance.
The comment period for the Interim Guidance document closed on February 22, 2021. TRC will monitor the docket for comments and provide an update when EPA issues further or final guidance.
TRC’s Air Management Services consulting group provides critical air quality support for facilities faced with challenges related to PFAS air emission testing, quantification, and permitting of applicable control devices.
Dr. Rachel Velthuisen
Dr. Rachel Velthuisen, Senior Project Manager with TRC has over 17 years of extensive air quality compliance experience, with a proven track record for managing multiple projects and clients to deliver high quality results across a range of industries. She provides expertise in Title V compliance and permitting, NNSR analysis, PSD permitting, regulatory compliance assessment, air emission inventories, and state minor source air permitting. She has worked with a variety of industries including chemical and textile facilities, large seaports, steel mini-mills, power plants, biosolids handling processing facilities, commercial airlines and the aerospace industry, detergent manufacturers, oil and gas extraction facilities, glass manufacturers, renewable electric-generating facilities, forest products, pulp and paper manufacturers, distilleries, paint manufacturers, renewable natural gas sites, among others. Dr. Velthuisen’s expertise lies in strategizing and leading multi-office teams to collectively provide client-focused and innovative solutions to complex air quality compliance challenges. She also leads TRC’s Air Management Services (AMS) PFAS group. Dr. Velthuisen has a Ph.D. and M.S. in Physical/Atmospheric Chemistry from the University of California, Irvine, and a B.S. in Chemistry from the University of Wisconsin, La Crosse.