Four parts per trillion. That is the Maximum Contaminant Level (MCL) for perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) in drinking water.
These are just two of the six per- and polyfluoroalkyl substances (PFAS) that received a MCL and Maximum Contaminant Level Goal on March 14, 2023. Despite being a drinking water standard, there is likely to be an influence on wastewater professionals.
“It won’t specifically, on its face, impact the wastewater side, but what we saw last year when the health advisories came out for drinking water … they tried to make analogous comparisons to wastewater. If EPA’s saying that this level of drinking water is not safe, then clearly if we found that amount in wastewater effluent or biosolids, then that also must not be safe,’” said Nathan Gardner-Andrews, National Association of Clean Water Agencies chief advocacy officer.
The MCL announcement is just one of many PFAS stress points in the industry. For example, the U.S. EPA published a proposal to add PFAS chemicals as hazardous substances under the jurisdiction of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), also known as Superfund, last fall. The agency is also conducting a risk assessment on the public health impacts of PFAS in biosolids, which is expected to be published in the coming months.
Combine the complex matter of PFAS with nutrient issues, communications and public affairs, and combined sewer overflow permitting, and wastewater professionals are in for a busy year.
Unpacking PFAS
The CERCLA hazardous substances designation is of grave concern for water and wastewater utilities as it could, in essence, place the burden of liability onto utilities that did not create the problem but rather are trying to directly address it through treatment.
“We’re concerned about the utilities ultimately getting stuck holding the proverbial bag from a legal liability standpoint and financial liability standpoint,” Gardner-Andrews said.
As such, NACWA and other industry associations have proposed to EPA to introduce an exemption for water and wastewater facilities, but the agency does not feel it has the legal authority to do so. Gardner-Andrews said this means policy professionals and utilities must engage Congress to establish this exemption, and that it will take an on-going effort.
This leaves EPA and its proposal in a tricky spot that could result in unintended consequences for addressing PFAS, the family of chemicals that has become a national talking point among the general public.
Adding to the unintended consequences is the risk assessment of PFAS in biosolids, the disposal of which uses either land application, beneficial reuse or incineration. The most common of these is land application and, when the PFAS risks are tied to the CERCLA proposal, the consequence extends beyond the water and wastewater utility sector into agriculture and landscaping.
“That’s become a real hotspot, if you will, with farmers being concerned about what it is doing to their land,” Gardner-Andrews said.
The initial findings of the EPA’s risk assessment are expected to be submitted to the scientific advisory board in the next few months. In the meantime, there are several states that are adopting their own rules on biosolids disposal, most notable of which was Maine’s banning of biosolids land application last year.
“The one landfill in the state that was taking biosolids has now said they’re not taking it anymore,” Gardner-Andrews said, referring to a report from the Portland Press Herald. “So you literally have this stuff piling up at treatment plants and they don’t know what to do about it.”
Utilities and associations attempted to warn the state legislature of the consequences of the ban, but the assembly followed through on the law. Other states holding similar regulatory discussions include Arizona and Oklahoma.
A critical stakeholder is the U.S. Farm Bureau, he added. Once land application is off the table, farmers are more likely to use chemical fertilizers, which have also been shown to contain PFAS chemicals.
Lastly, NACWA’s chief advocacy officer said he expects the MCL announcement to indirectly impact the wastewater sector. PFAS will once again be mainstream news, and the distinction between drinking water and wastewater is likely to make little difference in public perception.
He said the comparison is “apples to oranges,” but it will be made all the same. As such, it places some pressure on wastewater utilities to communicate more fully the nuances at play with PFAS chemicals in waterways. Gardner-Andrews said NACWA has communications resources available to members on its website for this and other communications matters.
Nutrient reduction goals
While PFAS detection, removal and disposal methods may have a new technology standard following the MCL, the standards for nutrient removal are nearing their limit. Impaired waterways throughout the U.S. that have point source regulations are still impaired, albeit less than they were at the start of nutrient reduction initiatives.
Regulators continue to release tighter nutrient targets to reach the ultimate goals for health of those waterways, but Gardner-Andrews said utilities are running out of ways to meet the ever-stricter targets, particularly in major watersheds like the Chesapeake Bay, the Mississippi River Basin, and the Puget Sound.
“We’ve gone to the limit of technology on a lot of point-source dischargers and we still have significant nutrient issues,” Gardner-Andrews said. “The challenge is going to be, from a regulatory standpoint, you can keep lashing down on the point sources and forcing them to install more technology, but it’s not going to solve the problem.”
He said the regulators are also in a bind because they cannot write permits that do not ensure compliance with water quality standards. Water quality has improved at the point sources, but the impairments related to nitrogen and phosphorus continue to present an issue.
“Even if impairments are coming from non-point sources, you have to wrestle with that and how you write a permit,” he said. “The EPA and states are aware of that, but they’re running out of options on how to deal with it.”
The focus, he said, has turned to watershed solutions or watershed permits rather than permitting a particular publicly owned treatment works to address the issue. This concept, he said, would look at all the entities within the watershed for a more holistic approach to water quality improvements.
Long-term CSO control plans
As the industry grapples with the impending squeeze on PFAS rules and nutrient loading, Gardner-Andrews said a “sleeping giant” issue lies with the long term combined sewer overflow control plans.
Initiated with the 1994 Combined Sewer Overflow (CSO) Policy under the Clean Water Act, these plans aimed to make utilities better control their CSOs over a long term, in some cases more than 20 years.
“There are now a number of communities that I refer to as the ‘tip of the spear’ that are coming out of their long term control plans,” Gardner-Andrews said. “They’ve done everything they said they’re going to do. They invested all their money, in some cases hundreds of millions or billions of dollars, to remediate CSOs, but, in many of those places, the water quality is still impaired.”
He stressed that these impairments have nothing to do with CSOs, but rather are related to urban stormwater runoff or upstream sources contributing to poor water quality. Connecting this with the aforementioned nutrient concerns, he said the conundrum lies with regulators who must write permits to address the impairments, despite the millions of dollars spent on improvements.
While this issue sits with only a few utilities at this moment in time, the number of utilities impacted will exponentially increase as they exit their long-term control plans in the next three to five years.
“I think it’s a potential sleeping giant of an issue because, if EPA ultimately can’t figure out how to thread this needle and they just fall back on, ‘Well, we don’t know what else to do,’ … that’s going to be a non-starter and it’s going to create huge political problems at the local level, and I think eventually at the national level,” he said.
