Bob Crossen is the senior managing editor for Water & Wastes Digest. Crossen can be reached at [email protected].
| Correction: This article has been revised since it was first published May 16, 2022. Portions regarding "regeneration" and "reactivation" of carbon have been either omitted or rewritten with links and verbatim language from legal resources and academic resources. |
The U.S. Department of Defense (DoD) announced a temporary halt on burning per- and polyflouroalkyl substances (PFAS) as a destruction and disposal method April 26, 2022.
According to the official memo from the DoD, this halt was initiated due to the 2022 National Defense Authorization Act (NDAA) “until DoD issues guidance implementing the U.S. Environmental Protection Agency interim guidance on the destruction and disposal of PFAS.”
Kristina Surfus, managing director of government affairs for the National Association of Clean Water Agencies (NACWA), said that this memo only directly impacts DoD activities. However, it has sparked conversations in Washington, D.C., regarding the matter of destruction and disposal of this family of chemicals often referred to as “forever chemicals.”
“It will not have a direct impact on wastewater facilities, who would be incinerating municipal biosolids – a very different product,” she said via email. “However, the ban does focus attention on how challenging the PFAS-waste management question is and how adequate destruction technologies do not exist.”
One of the growing areas of focus regarding the PFAS promulgation — or regulatory development process — is how to address PFAS in drinking water and wastewater. Water and wastewater treatment facilities are not producers of these chemicals, but they could be discharging them into the environment if they do not have proper treatment in place to manage them.
Treatment Methods & RCRA
The most common treatment methods for PFAS removal are granular activated carbon (GAC) and ion exchange (IX). In both cases, these treatment methods result in a PFAS-laden waste product, which must then be destroyed and disposed of properly. The PFAS waste is most commonly destroyed through incineration.
The term incineration is used in numerous contexts and a search in EPA’s Terms & Acronyms search returns 12 definitions, one of which comes from the Resource Conservation and Recovery Act (RCRA), which “gives EPA the authority to control hazardous waste from cradle to grave. This includes the generation, transportation, treatment, storage, and disposal of hazardous waste.”
Promulgation of PFAS detection, treatment, destruction and disposal is on-going, meaning the terms and definitions currently used may change over time. However, for the purpose of discussing PFAS destruction in the context of the DoD temporary burning halt, the RCRA definition is used.
The incinerator definition in RCRA can be found in 40 CFR 260.10 and is defined with the following verbatim language:
Incinerator means any enclosed device that:
- Uses controlled flame combustion and neither meets the criteria for classification as a boiler, sludge dryer, or carbon regeneration unit, nor is listed as an industrial furnace; or
- Meets the definition of infrared incinerator or plasma arc incinerator.
The law defines a sludge dryer as "any enclosed thermal treatment device that is used to dehydrate sludge and that has a maximum total thermal input, excluding the heating value of the sludge itself, of 2,500 Btu/lb of sludge treated on a wet-weight basis."
According to a Water Environment Research (WER) article titled, "Per- and polyfluoroalkyl substances thermal destruction at water resource recovery facilities: A state of the science review," sewage sludge incinerators have not been well studied as a destruction method. Looking at the data, the article notes that "in laboratory studies, more than 99% of PFOS is degraded at 600°C." Notable is the use of PFOS and not PFAS in this particular instance of the article.
Carbon regeneration units — defined as "any enclosed thermal treatment device used to regenerate spent activated carbon" by RCRA — are commonly run at 1000°C, which is a temperature referenced in the WER article previously mentioned.
While that does indicate promise, the article’s conclusion notes that further study surrounding incineration is necessary, specifically in reference to SSI for PFAS destruction.
“While nearly complete PFAS decomposition has been demonstrated at temperatures representative of SSI operation, by-products have also been observed,” the article concluded. “Temperature is only one of the three primary parameters when assessing destruction capacity in combustion systems, the other two being residence time and turbulence.”
As for carbon regeneration, a critical review titled "Thermal Regeneration of Spent Granular Activated Carbon Presents an Opportunity to Break the Forever PFAS Cycle" indicates thermal regeneration of carbon can destroy PFAS.
“This literature review on the engineered regeneration process illustrates the significant promise of this approach that can break the endless environmental cycle of these forever chemicals, while preserving the desired physicochemical properties of the valuable GAC adsorbent,” the abstract states.
PFAS in Biosolids
Tying this back into the matter of incineration as a disposal method, the issue gets more complex when biosolids from a wastewater treatment facility enter the equation. Surfus said there are commonly three ways that wastewater utilities manage their biosolids:
- Incineration;
- Landfills; and
- Beneficial reuse, often through land application as fertilizer.
NACWA’s stance is firm in that rules and regulations related to biosolids management, including when PFAS are involved, be driven by data. But when it comes to the issue of PFAS, assessments and understanding of the risks these chemicals pose on wastewater streams are lagging, as evidenced by the articles mentioned in above. While those articles shared the potential of certain methods and technologies, they did not conclude those methods were fully effective. Instead they note the need for further scientific review.
Furthermore, if the DoD temporary halt extends to other facilities and industries, it would set off a series of consequences that would negatively affect not only those facilities and industries but also the communities around those industries and facilities.
“Taking any biosolids disposal options off the table leaves communities with fewer options,” Surfus added. “Wastewater treatment costs will increase, and communities may be forced to significantly scale up landfilling. Critically, disposal of PFAS materials doesn’t actually destroy PFAS, so the root problem exists.”
The root problem to which Surfus referred is the manufacturing and proliferation of these man-made chemicals that are now pervasive in society. From non-stick pan coatings to fast food wrappers, these chemicals are found globally in water systems and in people’s blood.
Association & Legal Positioning
It has been the position of industry associations such as NACWA, American Water Works Association, Water Environment Federation, and others that water and wastewater utilities not be held liable for the waste streams from PFAS treatment. Instead, they have pushed regulators to hold manufacturers of PFAS chemicals liable and to have those manufacturers pay for damages and equipment to treat water contaminated by PFAS and other contaminants of emerging concern.
Legal firms have already taken notice of this industry position, and they have begun to target the manufacturers of these chemicals with lawsuits. One such example is SL Environmental, which held methyl tertiary-butyl ether (MTBE) polluters in New Hampshire accountable for pollution. The law firm secured a settlement that resulted in a state fund for utilities to tap for treatment equipment to manage the MTBE pollutant.
While that example is not specific to PFAS, SL Environmental has begun to pursue legal cases regarding PFAS pollution to hold the polluters accountable for those chemicals as well. Furthermore, Engineering News-Record reported “exponential growth” in the number of these lawsuits showing up in courts.
But not all cases are finding success. According to a Reueters report, a New York judge dismissed a lawsuit brought by Suez Water New York Inc. against multiple companies, which included E.I. Du Pont de Nemours and Co. This suit aimed to have those companies “pay for upgrades to five water-treatment plants in southern New York due to the companies' alleged role in pollution of the state's water with perfluoroalkyl and polyfluoroalkyl substances (PFAS),” the report states.
U.S. District Judge Lewis Liman in Manhattan dismissed the claims against E.I. du Pont de Nemours and Chemours for lack of specificity and other reasons, according to the Reuters report.
