Recent Projects – EPA

In 2023, EPA updated its emissions standards for heavy-duty engines and vehicles, but the agency now seeks to weaken many provisions of the 2023 Rule and spurns decades of agency practice and an enormous scientific record by declining to incorporate in its analysis any estimates of the impact of increased concentrations of particulate matter and ozone on human health. We submitted comments to EPA, along with our partners at Clean Air Task Force, Environmental Defense Fund, Montana Environmental Information Center, Natural Resources Defense Council, Sierra Club, and Union of Concerned Scientists, explaining that the agency’s new claim that these estimates are too uncertain is flawed for numerous reasons.

In 2024, the Environmental Protection Agency (EPA) set Maximum Contaminant Levels for six types of per- and polyfluoroalkyl substances (PFAS) under the Safe Drinking Water Act. Policy Integrity submitted a comment letter regarding EPA’s proposal to allow certain public water systems to request an additional two years to meet the standards for perfluorooctanoic acid and perfluorooctane sulfonic acid.

In 2024, EPA promulgated a final rule, Phasedown of Hydrofluorocarbons: Management of Certain Hydrofluorocarbons and Substitutes Under the American Innovation and Manufacturing Act of 2020. The 2024 Rule instituted leak-repair requirements for certain refrigerant-containing appliances containing hydrofluorocarbons (HFCs) or equivalents. HFCs are potent greenhouse gases (GHGs). EPA now apparently seeks to categorically exempt 360,000 road and intermodal container transport refrigeration units from the 2024 Rule’s leak-repair requirements. This letter identifies three legal flaws in the Proposed Rule.

In April 2026, the Environmental Protection Agency (EPA) proposed to rescind its 2024 risk-based standards for emissions of ethylene oxide from commercial sterilizer facilities. In doing so, EPA asserts that it lacks the necessary statutory authority under Section 112 of the Clean Air Act to update its residual risk review for these sources. We submitted comments to EPA explaining the agency's authority to update its residual risk review and associated standards. As we detail, Section 112(f) imposes no explicit limit on revising such findings, and both case law and statutory purpose support EPA's implicit authority to update its findings on the basis of new science.

For nearly thirty years, EPA has quantified and monetized the harmful effects of particulate matter and ozone, two lethal pollutants that threaten human health. The Trump Administration has abandoned these estimates, rejecting decades of research and instead claiming without support that the estimates are too uncertain. In February, EPA finalized a rule rescinding key updates to protections for hazardous air pollutants from coal- and oil-fired electric utility steam generating units. Several groups filed a Petition for Reconsideration urging EPA to reconsider the rule. We submitted comments supporting the petition, which explain the extensive scientific record undergirding EPA's estimates and demonstrate that EPA's arguments for abandoning these estimates are flawed and arbitrary.

For nearly thirty years, EPA has quantified and monetized the harmful effects of particulate matter and ozone, two lethal pollutants that threaten human health. This administration has abandoned these estimates, rejecting decades of research and instead claiming without support that the estimates are too uncertain. Several groups filed a Petition for Reconsideration urging EPA to reconsider the rule. We submitted comments supporting the petition, which explain the extensive scientific record undergirding EPA's estimates and demonstrate that EPA's arguments for abandoning these estimates are flawed and arbitrary.

For nearly thirty years, EPA has quantified and monetized the harmful effects of particulate matter and ozone, two lethal pollutants that threaten human health. Claiming the effects of these pollutants are too uncertain, EPA has recently announced that it is abandoning these estimates. In effect, EPA now values the health effects of these pollutants at zero. Jointly with other environmental and scientific organizations, we submitted comments on a recent proceeding regarding pollution from marine tank vessel loading operations where EPA failed to quantify or monetize these harms.

Section 401 of the Clean Water Act requires applicants for federal permits to conduct activities that “may result in any discharge into the navigable waters” to obtain a certification from the state where the discharge will originate. In January 2026, EPA proposed a rule that would restrict states’ ability to protect their water quality by narrowing states’ certification review to cover only projects’ discharges and not other water-quality impacts. Policy Integrity submitted a comment letter arguing that EPA’s proposed rule misapplies several Supreme Court precedents and mischaracterizes Section 401’s legislative history. In particular, the proposed rule is inconsistent with PUD No. 1 of Jefferson County v. Washington Department of Ecology, which upheld Section 401 conditions unrelated to discharges based on the Supreme Court's best reading of Section 401.

In December 2025, the Environmental Protection Agency (EPA) published a memorandum proposing to revise its final risk evaluation for formaldehyde. We submitted comments to EPA urging it to withdraw the memorandum, explaining that the agency’s assumptions are not supported by the best available science and run contrary to decades of cancer assessment guidelines and EPA’s own peer-reviewed findings.

The Environmental Protection Agency (EPA) has proposed to delay closure deadlines by three years for certain coal combustion residual surface impoundments. We submitted comments urging EPA to withdraw the proposal and explaining that the agency failed in its proposal to consider the costs of increased air pollution and to analyze other important forgone benefits.