Daniel W. Nelson Washington, D.C.
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Peter E. Seley Washington, D.C.
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The Environmental Litigation and Mass Tort Practice Group has been at the forefront of administrative law for almost two decades.  Our group has handled some of the most important environmental rulemaking challenges at the U.S. federal and state levels. 

The group's lawyers develop sophisticated comments to proposed rulemakings at the inception of regulatory action.  We are also deeply skilled in postpublication rulemaking challenges.   


The Environmental Litigation and Mass Tort group has handled some of the most important environmental rulemaking challenges at the U.S. federal and state levels. 

Recent representations include: 

  • Represented a coalition of automakers, engine manufacturers and auto dealers before the U.S. Supreme Court in the seminal case involving the EPA's authority to regulate greenhouse gas emissions from automobiles.  
  • Acted as lead counsel in the Cluster Rule litigation on behalf of several companies in the pulp and paper industry in the Ninth Circuit and the D.C. Circuit.  We were successful in transferring the case from the Ninth Circuit to the D.C. Circuit over the objections of the environmental petitioners and were successful in protecting the confidential business information submitted by the industry during development of the Cluster Rules.
  • Acted as lead trial counsel for a major wood products company in a regulatory challenge to the Clinton administration's 58.5 million-acre Roadless Initiative.  Successfully secured preliminary injunction in the District of Idaho halting the Roadless Rule.  Then, defended the injunction before the Ninth Circuit.
  • Representing automobile manufacturers in multiple challenges to state regulations limiting greenhouse gas emissions from motor vehicles. 
  • Submitted comments to the EPA on behalf of automobile manufacturer in opposition to the State of California's request for a pre-emption waiver under Section 209(b) of the Clean Air Act for its motor vehicle greenhouse gas regulations.  After the EPA denied the request and the State brought a challenge, Gibson Dunn successfully moved to intervene.
  • Represented an oil production facility in negotiating New Source Review terms and accomplishing a rule change from the South Coast Air Quality Management District for access to PM10 credits for use in permitting new electrical generating facility.
  • Represented a major oil company in a successful temporary restraining order proceeding in Santa Barbara County Superior Court to halt the implementation of a proposed rulemaking by the Santa Barbara County Air Pollution Control District.
  • Represented a public interest group in a federal suit that successfully forced the listing of the Atlantic salmon as an endangered species under the U.S. Endangered Species Act.
  • Represented an agricultural coalition in Endangered Species Act litigation.  The Center for Biological Diversity sued the Fish and Wildlife Service of the U.S. Department of the Interior to force the listing of the California tiger salamander under the U.S. Endangered Species Act.  Gibson Dunn intervened in this litigation on behalf of a coalition of interests that oppose the listing of this species in the absence of sound science indicating a listing is required.