“Brilliant at understanding statutes and regulations and then applying them to the facts on the ground”Chambers USA 2020

Claudia M. O'Brien

Washington, D.C.
  • 555 Eleventh Street, NW
  • Suite 1000
  • Washington, D.C. 20004-1304
  • USA

Claudia O’Brien, a partner in the Washington, D.C. office, is Co-Chair of the firm’s Environmental Regulation & Transactions Practice, former Chair of the Air Quality & Climate Change Practice, and former Vice Chair of the Finance Committee. She represents clients in agency petitions, rulemaking proceedings and litigation, as well as on compliance and enforcement, in a full range federal environmental statutes. Ms. O’Brien has particular experience in all aspects of the Clean Air Act and the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), as well as the Clean Water Act, the Resource Conservation and Recovery Act (RCRA), and the Endangered Species Act (ESA). She also advises on regulations impacting genetically engineered plants. She possesses specific technical and business knowledge of power plants (both fossil-fueled and biomass-fueled) and the pesticide industry, as well as extensive experience in toxicology and risk assessment.

Watch this video to learn more about
the Air Quality & Climate Change Practice

Ms. O’Brien joined the firm in 1994 after six years at the Environmental Protection Agency (EPA), where she worked on issues involving water, air, and toxic substances. While working full time at EPA, Ms. O’Brien attended law school at the Georgetown University Law Center.

Ms. O’Brien was a member of the Utility MACT Working Group, a subcommittee of the Clean Air Act Advisory Committee and is currently Vice Chair of the ABA’s Committee on Pesticides, Chemicals, and Community Right-to-Know. She is a co-author of “Walking the Line Between the Clean Air Act and the Federal Power Act: Balancing Emission Reductions and Bulk Power Reliability,” published in The Electricity Journal.

Ms. O’Brien has consistently been ranked by Chambers USA in its District of Columbia, Environment category since 2012. In 2021, she was included on Lawdragon 500’s Leading US Environmental & Energy Lawyers. Ms. O'Brien has also been named by Benchmark Litigation as a Litigation Star in the District of Columbia and recognized as one of the Top 250 Women in Litigation in the US from 2012-2016. She is listed in the International Who’s Who of Environmental Lawyers 2012-2020 for her “‘sector-leading expertise’ in relation to all aspects of the Clean Air Act and Clean Water Act.” Ms. O’Brien has also been included in the 2014-2017 and 2020 Expert Guides’ Women in Business Law for Environment – United States.

Ms. O’Brien is admitted to the Third, Fourth, Sixth, Seventh, Ninth, Tenth, and D.C. Circuits, as well as the US Supreme Court.  

Thought Leadership

Ms. O’Brien is a frequent author and contributor to Latham subject matter publications, including numerous client alerts and webcasts. In addition, recent publications include: 

  • "President Trump Takes First Step on Long Road to Roll Back Climate Rules," Client Alert (April 2017)
  • “Reducing Ozone Regulation Costs Under the New Administration,” Client Alert (March 2017)
  • “US Environmental Regulations to Face Rollbacks, but Reform Likely to be Tempered by Legal Barriers,” Latham.London (March 2017)
  • “President Signs Executive Order Directing EPA and Army to Review and “Rescind or Revise” Clean Water Rule,” Latham’s Clean Energy Law Report (March 2017)
  • “Re-Evaluating The Clean Water Rule: A Long Road Ahead,” Law360 (March 2017)        
  • “EPA Targets Oil and Gas Sector with Suite of New Emissions Rules,” Latham's Clean Energy Law Report, (May 2016)
  • “Proposed Rule from U.S. Department of the Interior Increases Pressure on Coal Mining Industry,” Client Alert (November 2015)
  • “EPA Proposes New Methane and VOC Emissions Limits,” Client Alert (October 2015)
  • “EPA Expands Air Quality and Climate Change Regulations,” Client Alert (October 2015)
  • “EPA Finalizes Historic Greenhouse Gas Emission Reduction Program,” Client Alert (August 2015)
  • “Proposed Rule from US Department of the Interior Increases Pressure on Coal Mining Industry,” Latham's Clean Energy Law Report, (July 2015)    
  • “The Supreme Court Strikes Down the Mercury and Air Toxics Standards,” Client Alert (July 2015)
  • “EPA’s Fiscal Year 2014 Civil Enforcement Results Reveal Agency’s Shifting Focus,” Client Alert (February 2015)
  • “CARB Invalidates Offsets for Facility’s Alleged RCRA Noncompliance,” Latham's Clean Energy Law Report, (November 2014)
  • “EPA Proposes Unprecedented Greenhouse Gas Emission Reduction Program,” Client Alert (June 2014) 
  • “The Supreme Court Upholds EPA’s Cross-State Air Pollution Rule,” Client Alert (May 2014)
  • “EPA’s Proposed Rule for New Power Plants Could Trigger Excessive Title V Permit Fees,” Client Alert (April 2014)
  • “States Voice Strong Opposition to EPA Clean Air Act Rule,” Client Alert (June 2013)
  • “EPA Proposes New Effluent Limitation Guidelines for Power Plants,” Law 360 (May 2013) 
  • “Implementing Carbon Taxes: Considerations, Realities, and Lessons Learned,” BNA (May 2013) 
  • “Using Disjointed Global and Domestic Climate Change Policies to the Client’s Advantage,” The Legal Impact of Climate Change (April 2013) 
  • “Outlining the Attempts to Invalidate California’s First GHG Auction,” (November 2012) 
  • “Getting the Deal Through – Climate Regulation 2013: United States,” (November 2012) 
  • “Walking the Line Between the Clean Air Act and the Federal Power Act: Balancing Emission Reductions and Bulk Power Reliability,” The Electricity Journal (January/February 2012) 
  • “Principles Promoting,” Project Finance (November 2011)
Clean Air Act

Ms. O’Brien has been deeply involved in Clean Air Act matters for more than two decades, beginning with her work developing regulations under Title IV of the Act. Her work includes advocacy and litigation in the following areas: 

  • National Ambient Air Quality Standard development and implementation, including deep involvement in the NOx SIP call, the Clean Air Implementation Rule, the Transport Rule, regional haze rules, and ozone and PM standard development and implementation 
  • New Source Review/Prevention of Significant Deterioration and operating (Title V) permits 
  • Emissions trading and averaging 
  • Hazardous air pollutant technology (MACT) and risk-based regulation, including work on more than a dozen MACT standards, and a deep understanding of EPA’s “Non-Hazardous Secondary Materials Rule” and its implications for regulatory treatment of combustion sources
  • New Source Performance Standards 
  • Mobile source and mobile source fuels 
  • Representative clients: Edison International, ReCommunity, American Forest & Paper Association, Navistar, Cinergy, JELD-WEN
Endangered Species Act (ESA) and National Environmental Policy Act (NEPA)

Ms. O’Brien has extensive experience in NEPA and the Endangered Species Act, successfully litigating numerous suits under both statutes. She has worked with clients on extensive ESA assessments on a range of issues and species, conducted advocacy with the relevant agencies, drafted NEPA comments, and drafted an 800-page Environmental Impact Report. Her work includes the following: 

  • Representing large energy project and extensive high voltage transmission lines on American Indian lands, requiring numerous federal approvals, including Bureau of Indian Affairs, Office of Surface Mining Reclamation and Enforcement, Environmental Protection Agency, Bureau of Land Management, and US Fish and Wildlife Service under the National Environmental Policy Act and Endangered Species Act.
  • Defended against an ESA “Mega Suit” obtaining dismissal of approximately 330 claims. 
  • Defeated an attempt to obtain an order compelling EPA to initiate consultation for atrazine, and to enjoin atrazine use across the country as an interim measure. 
  • Worked with the DOJ to craft the strategy, ultimately filed by DOJ, to move to dismiss or to transfer venue in the alternative – a strategy which resulted in dismissal of claim. 
  • Intervened on behalf of a client and aggressively defended the use of biotechnology. As a result, the Ninth Circuit upheld the agency’s deregulation of the product and rejected plaintiffs’ ESA and NEPA claims. This is the first Circuit decision confirming that ESA obligations regarding herbicide use did not apply to the Animal and Health Inspection Service in biotech deregulation decisions.
  • Represented client in environmental regulatory matters related to development of new genetically engineered crops, including NEPA; Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA); ESA; and Plant Protection Act issues. 
  • Acted as lead on NEPA and ESA issues for several LNG projects (on behalf of lenders and equity investors). 
  • Representative clients include Monsanto, CropLife America, the Blackstone Group, Syngenta, and lenders to Cameron LNG.
Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and Pesticide-Related Issues

Ms. O’Brien represents pesticide manufacturers in a range of issues under the FIFRA, including:

  • Regulatory counseling, advocacy, and litigation related to the registration and reregistration of pesticides, including responding to state and environmental group petitions and litigation, and advocacy related to proposed pesticide cancellations 
  • Litigation related to the treatment of pesticide applications under the Clean Water Act, as well as pesticide-related Endangered Species Act cases 
  • Negotiating and arbitrating data compensation cases, counseling on FIFRA Section 6(a)(2) issues, and addressing inert ingredient issues 
  • Regulatory advocacy and litigation regarding genetically engineered plants 
  • Representative clients: CropLife America, FMC Corporation, Syngenta, and Monsanto
Clean Water Act

Ms. O’Brien has remained involved in Clean Water Act issues since her work for EPA developing stormwater regulations and training regional and State personnel on water quality-based permitting, including use of whole effluent toxicity tests and toxicity reduction evaluations (TRE). Her work includes: 

  • Representing the State of Florida in its Original Action before the Supreme Court challenging the State of Georgia’s water consumption and its effects on the Apalachicola ecosystem
  • Regulatory advocacy and litigation on development of effluent limitation guidelines, and assistance in identifying and addressing issues related to total maximum daily loads (TMDLs)
  • Regulatory and permitting advocacy on the impact of thermal discharge and entrainment/impingement requirements for power plant cooling water intake structures
  • Regulatory advocacy and litigation on the treatment of pesticide applications under the Clean Water Act
  • Industry representation on implementation of the Reduction of Lead in Drinking Water law
  • Representative clients: State of Florida, CropLife America, Watts Water Technologies, the Lead Free Manufacturers Coalition, the Pharmaceutical Research and Manufacturers of America, and National Energy Group
Climate Change

Ms. O’Brien represents various clients evaluating the strategic impacts of climate change developments in the US and internationally. Her work includes: 

  • Legislative and regulatory advocacy on climate change bills and regulations
  • Assisting clients in understanding regional and global carbon markets, including negotiating “emission reduction purchase agreements” (ERPAs) 
  • Assisting clients in renewable energy project development, including evaluating potential offset development opportunities 
  • Representative clients: LS Power, the National Climate Coalition, RecycleRewards, Energy Capital Partners, E.On, PG&E, Goldman Sachs, Air Liquide, and CES Clean Energy Sol
Chemical-related Issues

Ms. O’Brien represents manufacturers in a range of cutting-edge risk and risk assessment-related issues, including: 

  • Obtaining “non-waste fuel” determinations for a range of secondary materials
  • Representation of clients in risk assessment proceedings under numerous federal and State programs, including under TSCA, RCRA, and the Clean Air Act 
  • Successfully challenging EPA’s refusal to remove methyl ethyl ketone from Section 313 of EPCRA, as well as successfully invalidating half of the chemical listings that were specifically challenged in a lawsuit over EPA’s expansion of the Toxics Release Inventory 
  • Representative clients: ReCommunity, the American Chemistry Council, Navistar, and the American Forest & Paper Association
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