Former U.S. EPA Senior Legal Counsel Zach Pilchen Rejoins Beveridge & Diamond, Strengthening Firm’s Air Capabilities

Beveridge & Diamond (B&D) is pleased to announce that Zach Pilchen has rejoined the firm as a Principal in our Washington, DC office. Zach brings significant government and private sector experience advising on complex environmental regulatory matters, with a particular focus on permitting, project development, enforcement, rulemaking, and administrative and appellate litigation arising under the federal Clean Air Act (CAA), American Innovation & Manufacturing (AIM) Act, and analogous state laws. 

Zach returns at a time when B&D’s robust air practice continues to grow as clients nationwide embark on energy, industrial, and data center infrastructure projects and face increasingly complex emission requirements. Zach left B&D in 2022 to accept an appointment as Senior Legal Counsel in the U.S. Environmental Protection Agency’s (EPA) Office of General Counsel, where he advised senior agency officials on high-profile regulatory initiatives and congressional oversight matters touching every major EPA program office.

Earlier in his career, Zach served at EPA as a career attorney focused on air and climate regulation, advising on dozens of CAA rulemakings involving federal-state regulatory issues. He also spent two years detailed to the U.S. Senate Committee on Environment & Public Works, where he helped draft and negotiate bipartisan environmental legislation, including the AIM Act, which established the federal program to phase down hydrofluorocarbons (HFCs).

“We are very excited to welcome Zach back to B&D,” said Firmwide Managing Principal Marc Goldstein. “His deep knowledge of EPA, particularly on air and climate change issues, combined with his understanding of how environmental policy and regulation are developed across the executive and legislative branches, will be tremendously valuable to our clients.”

Zach joins B&D’s robust air practice, counseling major corporations, trade associations, and public-sector clients across a range of industries on complex air quality and emissions matters. His practice includes stationary-source regulation and permitting, air and climate issues affecting energy, industrial, and data center projects, federal and state rulemakings, enforcement and compliance, mobile-source emission requirements, and regulation under the AIM Act and EPA’s Significant New Alternatives Policy (SNAP) program.  

Zach’s private sector experience includes:

• Advising clients on complex air permitting and project-development matters, including New Source Review (NSR) issues such as Prevention of Significant Deterioration (PSD) permitting, as well as Title V operating permits, source determinations, and project aggregation.
• Representing companies, trade associations, and municipalities in major EPA air and climate rulemakings under the CAA and AIM Act.
• Counseling automotive and transportation companies on evolving federal and state mobile-source emissions requirements.
• Defending companies in state air-enforcement matters and advising on voluntary disclosures under EPA’s Audit Policy and analogous state programs.
• Advising on transactions and project financing involving significant or novel air regulatory issues that could materially affect project feasibility, valuation, or liability.

“B&D is where I learned how to translate complex environmental law and policy into practical, strategic advice for clients, and I’m excited to return,” Zach said. “What’s always set B&D apart for me is its laser-like focus on environmental law and the collective depth of experience its lawyers bring to their work. It’s an invaluable combination for clients confronting complex, high-stakes, and increasingly interconnected environmental challenges.  I’m thrilled to be home.”

Beveridge & Diamond’s Air and Climate Change practice group helps private and municipal clients navigate all aspects of compliance and enforcement with Clean Air Act regulations. We frequently assist clients in commenting on and bringing administrative challenges to EPA rulemakings. Combining forces with our deep regulatory teams, our litigators represent clients in administrative rulemakings and appellate matters in numerous state and federal courts, including the D.C. Circuit and U.S. Supreme Court. Earlier this year, Chambers USA selected B&D as Environment Firm of the Year for 2026.