“Environmental Vanguard” is a quarterly newsletter from McGuireWoods, sharing key insights from our leading environmental attorneys and consultants at the forefront of regulatory, litigation, and policy developments. This issue covers EPA’s focus on “cooperative federalism” under the Trump Administration; the start of the process for a new “waters of the United States” rule; the Pipeline & Hazardous Materials Safety Administration’s (PHMSA’s) new advisory bulletin on pipeline safety management systems; EPA’s announcement that it plans to reconsider the Endangerment Finding; President Donald Trump’s executive memorandum freezing federal wind project approvals; and a recommendation for McGuireWoods’ sister newsletter, “Contaminants Compass,” which provides timely updates and analysis on evolving legal challenges involving per- and polyfluoroalkyl substances (PFAS).
Look for new editions every quarter, and feel free to reach out to the McGuireWoods team with questions about litigation, regulatory, enforcement, or other issues in environmental law.
EPA’s “Cooperative Federalism” Focus
EPA’s new deregulatory agenda under the Trump Administration aims to reduce regulatory burdens, promote domestic energy production, and shift decision-making authority back to state governments. One pillar of that agenda is the “Advancing Cooperative Federalism” initiative. The U.S. Supreme Court has described “cooperative federalism” as an arrangement that “offer[s] States the choice of regulating [an] activity according to federal standards or having state law pre-empted by federal regulation”—it envisions States and the Federal Government partnering on common goals. New York v. United States, 505 U.S. 144, 167 (1992). The Court has identified the Clean Water Act, the Resource Conservation and Recovery Act, and the Alaska National Interest Lands Conservation Act as examples of environmental laws that embody cooperative federalism. See id. at 167–68. For example, the Court has described the Clean Water Act as “anticipat[ing] a partnership between the States and the Federal Government, animated by a shared objective.” Arkansas v. Oklahoma, 503 U.S. 91, 101 (1992). The Advancing Cooperative Federalism initiative includes withdrawing the “Good Neighbor Plan,” resolving a backlog of state plans to regulate air emissions, and other goals.
In an address to the Environmental Council of the States, EPA Administrator Lee Zeldin described his understanding of cooperative federalism: “In developing our nation’s environmental statutes, Congress recognized the important role of states and their co-equal authority with EPA. Our legislators understood that states are best positioned to work with unique communities and implement laws. However, in too many instances and across too many Administrations, EPA has retained control of implementing many laws from its perch in the nation’s capital. It’s this kind of commonsense reform I want to partner with states to achieve.” Zeldin’s summary echoes the core idea of cooperative federalism as a partnership between States and the Federal Government.
EPA has taken several steps to begin implementing its vision of cooperative federalism. For example, on April 7, 2025, EPA announced that it was rescinding Guidance on the Preparation of Clean Air Act Section 179B Demonstrations for Nonattainment Areas Affected by International Transport of Emissions. According to EPA’s announcement, the guidance made it difficult for States to demonstrate that foreign air pollution is harming their citizens. EPA rescinded the guidance so that it can “work with state and local air agencies to develop the evidence necessary to grant regulatory relief under CAA Section 179b.” EPA acknowledged that this change responds to concerns voiced by local leaders, including by Arizona officials and business leaders during Zeldin’s recent trip to the State. The press release expressly tied the rescission of this guidance to EPA’s focus on cooperative federalism.
To take another example, Administrator Zeldin signed a final rule that approved West Virginia’s bid for Class VI Primacy under the Safe Drinking Water Act, which allows West Virginia to regulate certain underground CO2 injections. While the State’s request predated the Trump Administration, Zeldin’s approval was the fourth time a State successfully requested primacy of Class VI wells, and the third time during a Trump administration. Other approvals may be coming, as Administrator Zeldin has directed the Office of Water to more expeditiously review and approve other requests for state primacy under the Safe Drinking Water Act.
EPA’s focus on cooperative federalism may open additional possibilities for shifts in the regulatory landscape between federal and state regulation. Regulated entities will want to monitor these shifts to ensure ongoing compliance with both federal and state law.
EPA and Army Corps of Engineers Announce Listening Sessions for WOTUS Rule
EPA and the Army Corps of Engineers recently announced their intent to hold listening sessions to solicit input related to the development of a new “waters of the United States” (WOTUS) rule that complies with Sackett v. Environmental Protection Agency, 598 U.S. 651 (2023).
In 2023, the Supreme Court handed down the Sackett decision, which restricted federal jurisdiction over wetlands under the Clean Water Act. Under a previous plurality decision, wetlands qualified as WOTUS if those wetlands met one of two tests, as laid out in Rapanos v. United States, 547 U.S. 715 (2006). One test determined that wetlands could qualify as WOTUS if they maintained a “significant nexus” with traditionally navigable waters. Id. at 547 U.S. at 782 (Kennedy, J., concurring). The other, stricter test required that the wetland itself contain WOTUS, “i.e., a relatively permanent body of water connected to traditional interstate navigable waters,” and maintained a “continuous surface connection with that [WOTUS], making it difficult to determine where the ‘water’ ends and the ‘wetland’ begins.” Id. at 742 (Scalia, J., plurality opinion).
In Sackett, the Supreme Court unanimously adopted the stricter plurality test. In doing so, the Supreme Court greatly restricted jurisdiction over wetlands under the Clean Water Act and, more generally, the reach of the Clean Water Act and other statutes invoking jurisdiction over WOTUS. In the wake of the decision, the Biden Administration issued a conforming rule attempting to comply with Sackett, but litigation over EPA’s and the Corps’ definition of WOTUS continued.
Accordingly, EPA and the Corps announced their intention to issue a revised WOTUS rule. In the announcement—dubbed “The Final Response to SCOTUS”—EPA and the Corps implicitly acknowledged that its previous definitions and guidance were less than clear, stating that the agencies’ goal is to “provide clear and transparent direction.” Moving forward, EPA and the Corps would “prioritize practical implementation approaches” and “provide for durability and stability.” The goal is to create “more effective and efficient jurisdictional determinations, permitting actions, and other actions” that conform with Sackett and other Supreme Court precedent.
The announcement is in line with other stated priorities of the Trump Administration. Those potentially impacted have the opportunity to voice any concerns as the proposed rule works its way through the administrative process.
PHMSA Issues Advisory Bulletin on Pipeline Safety Management Systems
On March 25, 2025, PHMSA issued an advisory bulletin encouraging pipeline owners and operators to implement a pipeline safety management system (PSMS). As the advisory bulletin’s preamble explains, efforts by regulators and industry to promote adoption of PSMSs date back to 2010. After investigating a spill of more than 800,000 gallons of crude oil into the Kalamazoo River, the National Transportation Safety Board advised the American Petroleum Institute (API) to develop a safety management system standard specific to the pipeline industry. The resulting standard, API RP 1173: Pipeline Safety Management Systems, was first issued in July 2015. Many in the industry embraced the standard, as a report by the PSMS Industry Team shows that about 85% of total pipeline industry mileage is now covered by a PSMS. But many operators, and particularly smaller operators, have not yet implemented a system, though API RP 1173 is intended to be scalable.
PHMSA’s new advisory bulletin continues to encourage regulated pipeline owners and operators to implement a PSMS such as API RP 1173 and emphasizes that the standard’s essential elements and core principles can be tailored to create an effective program for operators of any size. According to the bulletin, a “PSMS, underpinned by a strong safety culture, makes safety programs and processes more effective to help prevent pipeline accidents.” Advisory bulletins do not carry the force of law and do not bind regulated entities. But this new bulletin carries forward a years-long trend toward implementation of safety management systems in the pipeline industry, both to encourage their creation as well as promote the evolution and improvement of existing systems.
EPA Plans to Reconsider Its 2009 Endangerment Finding
On March 12, 2025, EPA announced that it will begin a formal reconsideration of its 2009 Endangerment Finding. The Endangerment Finding determined that current and projected concentrations of six greenhouse gases threaten public health and welfare. EPA issued the Endangerment Finding two years after the Supreme Court held in Massachusetts v. EPA, 549 U.S. 497 (2007), that greenhouse gases fall under the Clean Air Act’s definition of “air pollutant” and were thus covered by that statute. When EPA first considered and made the Endangerment Finding, it received more than 380,000 public comments. EPA now says that it plans to reconsider this finding in light of the Supreme Court’s current administrative law jurisprudence, which has evolved since 2009, and “developments in innovative technologies, science, economics, and mitigation.” EPA plans to undertake the reconsideration in coordination with other federal agencies. As before, the reconsideration process will likely involve a period for public comment, and the result may engender litigation.
If EPA follows through on reconsidering the Endangerment Finding, the public comment period will be an important window of opportunity for parties to address the Endangerment Finding, whether and how EPA should reconsider it, and how a change in the Endangerment Finding would impact their industry.
Trump Issues Executive Memorandum Freezing Federal Wind Project Approvals
On January 20, 2025, President Trump issued an Executive Memorandum titled “Temporary Withdrawal of all Areas on the Outer Continental Shelf from Offshore Wind Leasing and Review of the Federal Government’s Leasing and Permitting Practices for Wind Projects” concerning the permitting and approvals required for wind projects. Although the title of the memorandum only mentions offshore projects, Section 2 addresses all wind projects, offshore and onshore. The memorandum halts federal wind energy leasing and directs federal agencies to cease issuing new or renewed permits and approvals for wind projects. As a result, many agency actions required for wind projects remain frozen at the federal level, pending agency reviews by administration officials as prescribed in the memorandum.
A review of typical agency consultations (such as with the U.S. Fish and Wildlife Service and State Historic Preservation Offices), determinations (such as Determinations of No Hazard to Air Navigation from the Federal Aviation Administration or Preliminary Jurisdictional Determinations from the U.S. Army Corps of Engineers), agreements with federal agencies, and permits that are issued for wind projects shows that a number of federal agency actions might not constitute permits or approvals affected by the memorandum. Thus, it is possible that a project could proceed without agency actions, possibly with some risk. While agreements between project proponents and federal agencies and non-issued permits are not yet clear, developers may still pursue satisfaction of consultation and determination requirements for projects.
The memorandum will likely have a significant impact on wind projects that are earlier in their stage of development. Projects that already have federal permits and approvals may be more likely to continue to development. In addition, developers may still pursue certain regulatory steps, such as consultations and determinations, and proceed to development. Consultations and determinations do not grant final approvals or permits necessary to proceed with full development and therefore might not be considered “permits or approvals” that are prohibited under the memorandum. If a developer proceeds with a project without agency consultation or determinations, the developer should ensure that it has detailed studies for species, air navigations, wetlands, etc., to make informed decisions about risk.
Keeping Up With Evolving PFAS Legal Challenges
The legal landscape concerning PFAS continues to evolve. Administrator Zeldin confirmed that PFAS are a priority for the Trump Administration, the proposed 2026 NPDES Multi-Sector General Permit contains new sampling procedures for evaluating PFAS in stormwater discharges, discussions over the designation of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) as hazardous substances under CERCLA continues to evolve, and PFAS-related litigation continues. For example, the U.S. Court of Appeals for the Fourth Circuit recently granted en banc review of a decision keeping open the possibility for 3M to remove PFAS cases from state court to federal court under the federal officer removal doctrine. McGuireWoods’ newsletter “Contaminants Compass” addresses evolving PFAS issues such as these on a monthly basis. If you face legal challenges involving PFAS and are not yet receiving Contaminants Compass, ask your McGuireWoods contact to add you to the distribution list.
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