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 in the agriculture, food processing, manufacturing, pipeline and energy sectors to navigate complicated state and federal environmental regulatory schemes, including those created by the Clean Air Act, Clean Water Act, California Porter-Cologne Water Quality Control Act, Oil Pollution Act, and RCRA. Darrin advises clients on compliance with environmental and safety rules affecting all phases of energy pipelines, from permitting and operation to emergency response planning. He closely tracks and advises clients on the latest developments in California and Federal efforts to regulate greenhouse gas emissions including the cap-and-trade program and measures to reduce methane emissions from oil and gas, waste, and dairy industries. Darrin has successfully advocated for the interests of his clients during the development of new environmental regulations, has advised his clients during the permit application process, 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.


Environmental Permitting

  • Advised agricultural, food processing, manufacturing, and energy clients on successful applications for air permits for new equipment including boilers, generators, pumps and other combustion sources; process equipment; compost operations and digesters; and coating booths. These complex permit applications include review of Best Available Control Technology, NSR and PSD requirements, modeling, emission reduction credits, and offsets.
  • Successfully negotiated favorable air permit terms and pursued appeals of unfavorable permit terms with several of the largest air districts in California including the San Joaquin Valley Air Pollution Control District, South Coast Air Quality Management District, Bay Area Air Quality Management District, and Sacramento Metropolitan Air Quality Management District. 
  • Negotiated the issuance of Coastal Development Permits in front of local agencies and the California Coastal Commission.
  • Guided clients through permitting and implementation of the complex California hazardous waste treatment program.

Pipeline Permitting, Operation, and Emergency Response

  • Assisted client in responding to reporting requirements and information requests from multiple federal and state agencies in the aftermath of an accidental release.
  • Managed technical experts retained to investigate potential damages in a Natural Resource Damage Assessment commenced under the Oil Polllution Act.
  • Advised clients on compliance with PHMSA and California State Fire Marshall pipeline safety and spill response planning requirements.
  • Assisted client in response to Corrective Action Orders issued by PHMSA regarding pipeline operations.

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

  • Advised energy and industrial clients on compliance with complex California Greenhouse Gas monitoring and reporting requirements.
  • Counseled clients in several industries regarding compliance issues with the Boiler MACT and emergency back-up generator provisions of the RICE MACT.
  • Represented large manufacturing companies in air permitting issues, including Title V compliance and deviation reporting.
  • 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.
  • Responded to requests for information from EPA  under the Clean Water Act and Clean Air Act.
  • Successfully negotiated reduced violations and penalties for alleged hazardous waste violations at a transportation business.

Professional, Community And Pro Bono Involvement

  • NatureBridge Yosemite, Board Member, 2016-present 
  • Western States Petroleum Association, 2018
  • Air and Waste Management Association
  • California Stormwater Quality Association
  • American Bar Association 
  • Bar Association of San Francisco 

Honors And Rankings

  • Order of the Coif

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