Darrin D. Gambelin

Darrin D. Gambelin


Darrin D. Gambelin


Darrin Gambelin draws on more than 20 years of experience with California and federal environmental laws to assist clients in resolving a range of permitting, compliance, and regulatory enforcement issues. 

He routinely works with clients to navigate complicated environmental regulatory schemes, including those created by the Clean Water Act, California Porter-Cologne Water Quality Control Act, Clean Air Act, and RCRA. Darrin has successfully advocated for the interests of his clients during the development of new environmental regulations and, when necessary has defended his clients in enforcement actions.

Prior to entering the field of law, Darrin had a productive career in the environmental compliance field, serving as an environmental, health, and safety professional in the manufacturing, waste management, and research industries. Using this hands-on experience, Darrin helps clients craft cost-effective and creative solutions to difficult environmental issues. He also prides himself on understanding the complex technical, scientific, and legal issues faced by clients.


EPA Clean Air Act Rulemakings 
  • Represented a large aerospace trade organization during EPA’s residual risk and technology review of the Aerospace Manufacturing and Rework NESHAP. Crafted detailed written comments in response to EPA’s proposed rule.
  • Represented an oil and gas trade association during the development of EPA’s oil and gas NSPS and NESHAP rulemaking. Successfully petitioned for reconsideration of the rule address client’s needs.
  • Represented a large auto manufacturer in the residual risk and technology review of the secondary aluminum NESHAP. Successfully advocated for several key changes to the rule.  
Compliance Counseling
  • Counseled large manufacturers regarding compliance issues with the Boiler MACT and emergency generator provisions of the RICE MACT.
  • Represented a large manufacturing company in permitting issues.
  • Advised a medical waste incineration company on permitting and compliance issues.
Enforcement Defense
  • Defended an oil and gas company against an enforcement action relating to crude loading at a marine terminal.
  • Assisted with the defense of a large energy company in the criminal enforcement of Clean Air Act violations.

Professional, Community And Pro Bono Involvement

  • Board Member, NatureBridge Yosemite 
  • Member, Air and Waste Management Association
  • Member, California Stormwater Quality Association
  • Member, Central Valley Clean Water Association
  • Member, American Bar Association 
  • Member, San Francisco Bar Association 

Honors And Rankings

  • Order of the Coif

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