EPA Issues Drinking Water Contaminant List


Earlier this week, the U.S. Environmental Protection Agency published its Final Fifth Drinking Water Contaminant Candidate List (CCL 5), including an expansion of per- and polyfluoroalkyl substances (PFAS). This list will serve as the basis for the EPA’s regulatory considerations over the next five-year cycle under the Safe Drinking Water Act. 

“Following public engagement and robust scientific review, the final contaminant candidate list is the latest milestone in our regulatory efforts to ensure safe, clean drinking water for all communities,” said EPA Assistant Administrator for Water Radhika Fox

“As EPA takes action to protect public health and the environment from PFAS, including proposing the first nationwide drinking water standards later this year, today’s final CCL 5 looks further forward to consider additional protective steps for these forever chemicals.”

The EPA reports that the update is an important first step towards identifying additional PFAS that may require regulation under the Safe Drinking Water Act since publishing the PFAS Strategic Roadmap a year ago. Additionally, the announcement strengthens its commitment to protect public health from impacts of PFAS and support the Agency’s decision-making for potential future regulations of PFAS.

The Final CCL 5 includes 66 chemicals, three chemical groups (PFAS, cyanotoxins and disinfection byproducts [DBPs]), and 12 microbes, which were selected from a universe of chemicals used in commerce, pesticides, biological toxins, disinfection byproducts and waterborne pathogens.

According to the release, in developing the Final CCL 5, the EPA requested public nominations, providing an opportunity for people to make recommendations to the Agency about specific contaminants of concern that may disproportionally affect their local community. 

The process was then enhanced based on the comments received by prioritizing data most relevant to drinking water exposure, improving considerations of sensitive populations including children, and considering the recommendations included in the Review of the EPA’s Draft Fifth CCL 5 report from the Science Advisory Board. 

A full list of chemical contaminants in the CCL 5 can be found here.

PFAS Strategic Roadmap

A year ago, EPA Administrator Michael S. Regan announced the creation of the Agency’s PFAS Strategic Roadmap to address contamination regarding per- and polyfluoroalkyl substances.

The PFAS Strategic Roadmap officially sets a series of timelines for the EPA to take specific actions and set bolder policies regarding PFAS. In addition, the plan also pledges to conduct more research and testing on hundreds of other PFAS, potentially listing additional compounds as hazardous substances in the future to better safeguard public health, protect the environment and hold polluters accountable.

By 2023, the roadmap aims to set a final rule for PFOS and PFOA regulation in drinking water and will designate two compounds as hazardous substances. That same year, the Agency intends to provide updated research on the available methods for disposing of or destroying PFAS through landfills, thermal treatment and deep-well injection.

EPA’s integrated approach to PFAS is focused on three central directives:

  • Research - Invest in research, development and innovation to increase understanding of PFAS exposures and toxicities, human health and ecological effects, and effective interventions that incorporate the best available science;
  • Restrict - Pursue a comprehensive approach to proactively prevent PFAS from entering air, land and water at levels that can adversely impact human health and the environment; and
  • Remediate - Broaden and accelerate the human health and ecological systems.

A full copy of the PFAS Strategic Roadmap can be viewed here.

Later that month, the EPA asked its Science Advisory Board to review draft documents regarding health effects of per- and polyfluoroalkyl substances. The request for review was a result of recent scientific data regarding the negative health effects of lower levels of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) than previously understood and that PFOA is likely a carcinogen.

The four draft documents include:

  • Proposed Approaches to the Derivation of a Draft Maximum Contaminant Level Goal for PFOA in Drinking Water;
  • Proposed Approaches to the Derivation of a Draft Maximum Contaminant Level Goal for PFOS in Drinking Water;
  • Draft Framework for Estimating Noncancer Health Risks Associated with Mixtures of PFAS; and
  • Analysis of Cardiovascular Disease Risk Reduction as a Result of Reduced PFOA and PFOS Exposure in Drinking Water.

According to the EPA, following peer review, this information will be used to develop Maximum Contaminant Level Goals and a National Primary Drinking Water Regulation for PFOA and PFOS. The agency is also seeking independent scientific review of these documents.

“EPA will not wait to take action to protect the public from PFAS exposure. The agency will be actively engaging with its partners regarding PFOA and PFOS in drinking water, including supporting their monitoring and remediation efforts,” stated the press release, also citing the recent Bipartisan Infrastructure Law, which invests $10 billion to help communities test for and clean up PFAS and other emerging contaminants in drinking water and wastewater

The EPA plans to develop a proposed PFAS National Primary Drinking Water Regulation for fall 2022.

State PFAS Drinking Water Rules

In March, the Pennsylvania Department of Environmental Protection proposed a new regulation to set maximum containment levels (MCLs) in drinking water for two forms of per- and poly-fluoroalkyl substances, perfluorooctane sulfonic acid and perfluorooctanoic acid.

Currently, there are no state or federal MCLs for PFOA and PFOS. Per the Pennsylvania Safe Drinking Water Act, the Environmental Quality Board (EQB) can adopt MCLs or treatment technique requirements without federal standards.

The proposed state rule would set an MCL of 14 parts per trillion for PFOA and an MCL of 18 parts per trillion for PFOS, which are reportedly stricter limits compared to the Environmental Protection Agency’s lifetime Health Advisory Level of 70 parts per trillion for both substances combined.

According to the rule, the proposed MCLS will applied to all 3,117 water systems in the state. 1,905 of those systems are reportedly community water systems, serving 11.4 million residents, and 1,096 of these are nontransient noncommunity water systems that serve 507,000 people.

Once in effect, initial compliance monitoring will begin as follows:

  • For community and nontransient noncommunity water systems serving a population of greater than 350 persons and all bottled, vended, retail and bulk systems begins January 1, 2024; and
  • For community and nontransient noncommunity water systems serving a population of less than or equal to 350 persons begins January 1, 2025.

The proposed rule, published at the end of last month in the Pennsylvania Bulletin, can be found here. The public comment period for the rule closed April 27.


Tagged categories: Construction chemicals; Environmental Protection Agency (EPA); Government; Hazards; Health & Safety; Health and safety; NA; North America; potable water; Program/Project Management; Regulations; Water/Wastewater

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