Eric Waeckerlin

Eric Waeckerlin



Accomplished lawyer providing legal guidance across numerous state and federal environmental, air quality, public lands and natural resource issues. At the forefront of emerging federal and state methane and climate change regulatory efforts affecting the energy and industrial sectors. Pairs technical knowledge with deep understanding of clients’ businesses to find pragmatic solutions to complex problems. 

A widely respected environmental lawyer, Eric Waeckerlin employs a solution-oriented approach in resolving all stages of complex environmental permitting, enforcement, policy and regulatory matters. He represents clients in major litigation in federal and state courts, and before administrative agencies over critical air quality and other environmental and natural resource issues affecting numerous industries. He routinely advises clients on a range of environmental issues arising during transactional due diligence.

Eric represents energy infrastructure companies including oil and natural gas operators and pipeline companies, as well as mining interests, defense contractors, steel manufacturers, engine and other mobile source manufacturers, and industry trade associations on numerous issues under the Clean Air Act, Clean Water Act, Resource Conservation and Recovery Act, National Environmental Policy Act, CERCLA and their state equivalents. At the forefront of emerging federal and state methane, carbon capture and climate change regulatory efforts affecting the oil and natural gas sector. Eric is frequently called upon to represent companies in high-stakes policy and regulatory matters before the Environmental Protection Agency and the Bureau of Land Management as well as state environmental agencies and oil and gas conservation commissions across the Rocky Mountain West.

Prior to Brownstein, Eric practiced in Denver and in Washington, D.C., advising energy, manufacturing and industrial clients.

Representative Matters

Recent Experience

  • Regulatory counsel to upstream and midstream oil and gas entities on methane emission reduction innovation and monitoring efforts, including the Inflation Reduction Act’s (IRA) Methane Emissions Reduction Program (MERP).

  • Environmental counsel to the largest construction company in the United States, advising on all aspects of environmental compliance at a major chemical demilitarization facility in Colorado.

  • Counsel to major emerging developer of domestic energy and clean energy projects, advising on federal and state air quality, hydrogen, carbon capture and sequestration, and alternative and clean fuel regulatory policy.

  • Counsel to Fortune 500, international oil and gas company, providing advice on a variety of groundbreaking air quality and climate change regulatory and legislative matters.

  • Lead counsel for national oil and gas trade associations in successful nationwide challenge to the United States Bureau of Land Management’s Waste Prevention rule governing oil and gas operations on federal and Indian lands.

  • Lead counsel for multiple E&P and midstream oil and natural gas companies defending against multi-million dollar air quality enforcement matters brought by the United States Environmental Protection Agency and equivalent state air quality agencies.

  • Work with multiple E&P companies on legacy liability related to plugging and abandonment (P&A), structural well integrity, and complex technical investigations into potential soil and groundwater contamination from conventional and unconventional operations including hydraulic fracturing.

  • Lead defense counsel  for one of the largest private producers of onshore crude oil and natural gas against a significant enforcement action related to federal New Source Performance Standards.

  • Defense counsel to multiple midstream oil and natural gas companies related to information requests and pending enforcement matters associated with federal environmental laws.

Insights & Publications



  • J.D., 2005, University of Montana School of Law
  • M.S., 2001, Duke University
  • B.S., 1998, University of Wyoming


  • Wyoming
  • District of Columbia
  • Montana
  • Colorado


American Bar Association

  • Climate Change, Sustainable Development, and Ecosystems Committee, Vice Chair
  • Superfund and Natural Resources Damages Litigation Committee, Vice Chair



"Eric is extremely responsive, with expertise in air emissions and dealing with the EPA and other agencies." "An excellent attorney that does excellent work." Chambers USA, 2022

"He has a very deep knowledge base and technical expertise when it comes to environmental regulations." "He's a very good attorney and well known for the quality of his work." Chambers USA, 2021

5280 Top Lawyers, 2021-2024

Chambers USA, 2020-2023

Best Lawyers in America, 2018-2024

Denver Business Journal, Who's Who in Energy, 2017