By Jay Landers

In April, the U.S. Environmental Protection Agency released two much-anticipated final rules pertaining to certain contaminants within the broad class of synthetic compounds known as per- and polyfluoroalkyl substances. Commonly referred to as forever chemicals because of their long-lasting nature, PFAS have emerged as a chief source of contamination in drinking water supplies across the U.S. in recent years.

On April 10, the EPA released a pre-publication version of its final rule for PFAS in drinking water, setting limits for several individual forms of PFAS, mandating monitoring and notification requirements, and setting a five-year deadline for water providers to implement capital solutions to treat water supplies in excess of the new limits. The final rule comes amid recent legal settlements in which certain PFAS manufacturers have agreed to pay billions of dollars to water utilities affected by the contaminants.

On April 19, the EPA issued a pre-publication version of its final rule, designating two PFAS – perfluorooctanoic acid and perfluorooctanesulfonic acid – as hazardous substances under the Comprehensive Environmental Response, Compensation, and Liability Act, the federal law governing the hazardous waste remediation program commonly known as Superfund. Although the agency sought to dispel fears that water and wastewater utilities and other “passive receivers” of PFAS will be targeted under CERCLA, industry groups expressed concern that the sector still could be forced to pay to clean up PFAS contamination that it did not cause.

Nationwide endeavor

Long used for industrial and commercial purposes, including as part of firefighting foams, nonstick cookware, and stain-resistant furniture, PFAS are now considered threats to human health. “PFAS exposure over a long period of time can cause cancer and other serious illnesses that decrease quality of life or result in death,” according to the EPA’s fact sheet on its final rule for PFAS in drinking water. “PFAS exposure during critical life stages such as pregnancy or early childhood can also result in adverse health impacts.”

By helping reduce PFAS levels in drinking water, the final rule “will reduce PFAS exposure for approximately 100 million people, prevent thousands of deaths, and reduce tens of thousands of serious illnesses,” according to the EPA’s April 10 news release announcing the final rule.

In the U.S., addressing PFAS contamination of drinking water is a “crucial nationwide endeavor,” says Kyle Thompson, Ph.D., P.E., the national PFAS lead for the water engineering consulting firm Carollo Engineers, resulting in large part from the widespread historical use of PFAS in jet-fuel firefighting foams at airports – both civilian and military – around the country. Along with such industrial uses as electroplating, another common source is leachate from landfills that have received consumer products that include PFAS, Thompson says.

Maximum contaminant levels vary

Among its key requirements, the final rule sets maximum contaminant levels for five individual PFAS as well as a hazard index level MCL for two or more of four PFAS as a mixture. The individual MCLs total 4 parts per trillion for perfluorooctanoic acid and perfluorooctane sulfonate and 10 ppt for perfluorononanoic acid, perfluorohexanesulfonic acid, and hexafluoropropylene oxide dimer acid.

Because of concerns about the additive health effects of certain PFAS even when individually present at low levels, the EPA in its final rule has deployed a hazard index MCL of 1 for mixtures of two or more of PFNA, PFHxS, HFPO-DA, and perfluorobutane sulfonic acid. The unitless hazard index consists of a sum of fractions, each of which “compares the level of each PFAS measured in the water to the health-based water concentration” set by the EPA, according to its fact sheet. If an annual average of quarterly sampling data for the four chemicals results in a hazard index greater than the MCL of 1, a violation has occurred.

For its part, the EPA “estimates that between about 6% and 10% of the 66,000 public drinking water systems subject to this rule may have to take action to reduce PFAS to meet these new standards,” according to the agency’s April 10 release.

Although ASCE has not taken a formal position on the final rule, “we do certainly recognize how momentous this is,” as the first primary drinking water standard to address PFAS, says Matthew McGinn, a senior manager for government relations at the Society. “We're all aware of the health risks that they bring,” McGinn says. “ASCE supports an approach which provides a balance for drinking water quality with risk-based contaminant limitations that include adverse health effects and their frequency of occurrence.”

Initial and ongoing monitoring

Within three years of the promulgation of the final rule, public water systems must begin initial monitoring for PFAS at all entry points to their distribution system. For all surface water systems and groundwater systems serving more than 10,000 customers, monitoring must be conducted quarterly within a 12-month period and samples must be collected 2-4 months apart. Groundwater systems serving 10,000 or fewer customers are required to monitor twice within a 12-month period, and samples must be collected 5-7 months apart. In certain cases, public water systems may be able to use previously collected monitoring data.

Initial monitoring results will determine the frequency of ongoing compliance monitoring. Water providers will be required to include the results of their ongoing compliance monitoring as part of their consumer confidence reports, the annual water quality summaries that utilities must provide their customers.

Water providers whose drinking water is found to exceed the new PFAS-related MCLs will have five years following the final rule’s promulgation to comply with the standards and notify the public of violations.

Compliance deadline extended

The five-year compliance deadline is one of the key differences between the final rule and the proposed rule, which the EPA released in March 2023. The EPA’s decision to add two years to the compliance window is a positive step, Thompson says. “It's really going to help a lot of utilities,” he says. In particular, water providers requiring custom-made treatment systems, rather than simply the more readily available prefabricated versions, stand to benefit from the compliance window extension, Thompson notes. “That kind of infrastructure takes a long time to build.”

Moreover, the additional two years for achieving compliance offers water providers more time to engage in enhanced public communications. Thompson highlights the opportunity for utilities, who will start reporting PFAS exceedances three years from now, to leverage the growing public awareness about these chemicals. “With ample scientific knowledge and data on PFAS, utilities are in a prime position to offer proactive, community-specific communications to their customers regarding PFAS levels and viable treatment options,” he says.

Although it does not specify the type of treatment systems that water providers must use, the EPA has identified four “best available technologies” for achieving the PFAS-related MCLs: granular activated carbon, anion exchange, reverse osmosis, and nanofiltration.

Thompson points to the promising prospect of emerging technology to separate or destroy PFAS. Nonetheless, in the short term, “there’s going to be unprecedented demand for the established PFAS treatment materials,” he says. This demand could lead to acquisition delays and increasing costs, he notes.

With this in mind, water providers may benefit greatly by identifying the sources of PFAS in their water and working to reduce the contamination at its origins, Thompson says. “It's a really good idea before getting started on treatment to try to assess and understand the PFAS sources,” he says. “That raises a lot of options for solutions that may be more cost-effective or more fair than doing the kind of conventional centralized treatment at the utility.”

Benefits and costs

The final rule “will prevent thousands of deaths and reduce tens of thousands of serious illnesses that would be attributable to long-term exposure to these PFAS,” according to an EPA fact sheet regarding the benefits and costs associated with the rule. The agency estimates that such benefits will amount to approximately $1.549 billion annually.

The EPA estimates that the costs associated with the final rule will total roughly $1.548 billion per year, most of which will result from water system treatment and disposal. However, water industry representatives maintain that the agency has failed to adequately estimate the true costs of the rule.

For example, the American Water Works Association “is concerned that the rule’s health and financial impacts are not accurately characterized,” according to an April 10 statement from the association. “AWWA estimates the cost of the rule is more than three times higher than the agency’s calculations. The magnitude of these additional costs will lead to affordability challenges in many communities.”

The National Rural Water Association highlighted the potential burden that the final rule will place on smaller water providers. “NRWA applauds EPA for providing utilities with time and flexibility to comply with the new PFAS National Primary Drinking Water Regulation, but we recognize that the requirements will have disproportionate impacts on small, disadvantaged, and rural communities that lack the financial and managerial capacity to make upgrades,” the association said in an April 10 news release. “Federal funding dedicated to rural communities must serve as a lifeline, providing essential support for the development, improvement, and maintenance of vital infrastructure.”

Signed into law in November 2021, the bipartisan infrastructure law provided $9 billion for addressing PFAS in drinking water. However, this federal funding will not suffice, according to the Association of Metropolitan Water Agencies.

“While we appreciate that there is some bipartisan infrastructure law funding available for utilities, the money will not cover the billions of dollars in operations and management costs that will be required as long as these chemicals are present in our nation’s drinking water sources due to the manufacture and use of PFAS broadly in commerce,” said AMWA CEO Tom Dobbins in an April 10 news release.

Settlements offer potential funding

Recent settlements involving PFAS manufacturers and water utilities offer another source of funding.

After hundreds of water utilities and other entities began filing claims for damages against certain PFAS manufacturers, the cases were consolidated, in 2018, into a single proceeding to be overseen by the U.S. District Court for the District of South Carolina. Known as the Aqueous Film-Forming Foam Product Liability Litigation, the multidistrict litigation represents several categories of claims, including public water providers seeking damages associated with the costs of testing and remediating drinking water.

As of late April, the AFFF litigation had resulted in three settlements involving drinking water systems and PFAS manufacturers. In September, chemical giants DuPont and 3M entered into separate settlements in which DuPont agreed to pay nearly $1.2 billion and 3M agreed to pay up to $12.5 billion to public water systems affected by PFAS. The court approved the settlements earlier this year.

On April 12, a law firm representing plaintiffs in the AFFF litigation announced a $750 million settlement agreement with Tyco Fire Products, a subsidiary of Johnson Controls. The Tyco settlement still must be approved by the court.

In determining the amounts of payments that participating water providers will receive, the AFFF settlements “use an allocation methodology that assigns a score to every PFAS-impacted source,” says Ken Sansone, a senior partner at SL Environmental Law Group PC, one of a group of law firms representing various plaintiffs in the AFFF litigation.

This score is the “product of two sets of factors,” Sansone notes. The first set involves the “severity of the impact measured as the highest concentrations of PFOA and PFOS that have ever been detected in the source,” he explains. “The other set of factors depend on the size of the source, both in terms of its maximum production capacity and its historical record of production.” In addition, the settlement includes various “multiplication factors” that can be used to increase payments further, he says.

Although supportive of the settlements, AMWA views them as insufficient to address the extent of PFAS contamination in drinking water. “While AMWA appreciates that 3M and other chemical companies are being held accountable for their role in contaminating drinking water sources with PFAS contamination, the overall amount of the settlement is a fraction of what community water systems and ultimately their ratepayers will pay to remove these chemicals from our drinking water,” Dobbins said in an April 5 release. “We look forward to working with Congress to develop additional funding sources to help communities offset the remaining costs of addressing PFAS in their water supplies.”

Residual concerns

As the EPA prepared to finalize its rule designating PFOA and PFOS as hazardous substances under CERCLA, water and wastewater groups repeatedly warned that such a designation could harm their members by holding them liable for PFAS contamination that they receive from other sources. Of particular concern is the disposal of treatment residuals containing PFOA or PFOS.

In announcing the release of its new final rule, the EPA emphasized that it has no plans to target water and wastewater utilities and certain other groups as part of PFAS-related actions under CERCLA. “EPA’s enforcement policy, consistent with EPA’s past practice over decades of implementing the law, will provide additional clarity on the agency’s intent not to pursue certain parties such as farmers, municipal landfills, water utilities, municipal airports, and local fire departments, where equitable factors do not support seeking CERCLA cleanup or costs,” according to the agency’s April 19 news release. On the same day, the EPA released a memorandum, titled “PFAS Enforcement Discretion and Settlement Policy under CERCLA,” spelling out the details of its new enforcement discretion policy.

However, the water sector derived little reassurance from the EPA’s promise of enforcement discretion. “The final rule from EPA puts water systems at risk, will translate to higher costs for ratepayers, and opens water systems up to costly litigation,” according to a statement issued April 19 by AWWA on behalf of the Water Coalition against PFAS. Besides AWWA, the coalition comprises AMWA, the National Association of Clean Water Agencies, the National Association of Water Companies, NRWA, and the Water Environment Federation.

“The ‘enforcement discretion’ memo simultaneously released by the EPA shows that the agency does not believe that water systems are the problem, but the reality of this final rule means that utilities will face increased operational costs and uncertainties and, most worrisome, will be the target of endless litigation from the manufacturers of PFAS,” according to the statement. “Even if specific legal action from polluters fails, the litigation costs alone will be enough to financially strain water systems and result in increasing costs for customers.

“With the rule now finalized, Congress must act immediately to uphold CERCLA’s ‘polluter pays’ principle and provide a statutory liability shield for water systems related to PFAS cleanups.”

As it happens, legislation to do just that was introduced in the House on April 11 by Rep. John Curtis, R-Utah. Titled the Water Systems PFAS Liability Protection Act (H.R. 7944), the bill would exempt from CERCLA liability related to PFAS releases the following entities: public water systems, publicly or privately owned or operated treatment works, municipalities operating under Clean Water Act permits for stormwater discharges, wholesale water agencies, and contractors for any of those four groups.

H.R. 7944 enjoys the support of the Water Coalition against PFAS, according to an April 18 news release from NAWC. The bill is a companion to a measure having the same name that was introduced in the Senate in May 2023 by Sen. Cynthia Lummis, R-Wyo. Part of a suite of bills introduced by Lummis to protect certain industries from CERCLA liability pertaining to PFAS, S. 1430 also is supported by the Water Coalition against PFAS.

Meanwhile, technological advancements could help the water sector address the current “uncertainty” regarding the legal implications of PFAS-laden treatment residuals, says Chad Seidel, Ph.D., P.E., the president of Corona Environmental Consulting LLC. Currently, standard approaches for addressing PFAS in drinking water simply remove the contaminants rather than destroying them, Seidel notes. “You're just moving the PFAS from water to a different phase.”

Fortunately, an ongoing “gold rush” of research and development is expected to devise new methods for destroying PFAS once they have been removed from drinking water, Seidel says. Potential solutions include electrochemical oxidation, supercritical oxidation, and plasma-based destructive approaches. “I do think our community is up for the task,” he says. “We'll address this and do so as effectively and efficiently as possible and hopefully innovate our way to some better solutions along the way.”

This article is published by Civil Engineering Online.