Skip to Main Content
Person Photo
Person Photo

Thomas Sansonetti

Partner

6380 South Fiddlers Green Circle, Suite 500, Greenwood Village, CO 80111
P 303.290.1061
2515 Warren Avenue, Suite 450, Cheyenne, WY 82001
901 K Street NW, Suite 850, Washington, DC 20001
OVERVIEW

A longtime litigator and project team leader, Tom Sansonetti helps clients permit and develop projects with potential obstacles in mind.

Long before a lawsuit can threaten a project, he counsels clients on how to develop effective plans of action that will meet government environmental permitting requirements and stand up to judicial scrutiny when those clients' projects are challenged in court.

Tom joined Holland & Hart in 1993 and built a nationally recognized practice in natural resources and environmental law. Considered an expert in natural resources and environmental matters, Tom served as an Assistant Attorney General for the Environment and Natural Resources Division in the Department of Justice and also as the Solicitor at the Department of the Interior. He has argued before the U.S. Supreme Court and in six Federal Circuit Courts of Appeal, and served as a federal prosecutor in environmental crimes cases. Tom’s appellate experience highlights his ability to argue cases at all levels of the federal court system.

show more
EXPERIENCE

Experience

Experience in many areas of energy and natural resources law, including:

  • American Indian law
  • Appeals of adverse federal agency decisions before the Interior Board of Land Appeals and Interior Board of Indian Appeals
  • Clean Air Act and Clean Water Act issues
  • Development of renewable energy projects, including geothermal, solar, and wind projects
  • Endangered Species Act
  • Oil and natural gas permitting
  • Permitting of oil and natural gas pipelines and electric transmission, including right-of-ways
  • Public lands management
  • Surface mining development and reclamation
  • Water rights
CLIENT RESULTS

Client Results

Energy and Natural Resources Projects
  • Team leader for permitting natural gas pipeline through four states and 680 miles.
  • Represented a regional natural gas pipeline operator in negotiations with tribes to purchase a major natural gas pipeline.

  • Represented various companies in obtaining rights-of way over state, federal, and tribal lands.

  • Represented an international geothermal company in their negotiations to place a project on an American Indian reservation.
  • Represented a company in the negotiation with an American Indian tribe for the construction of a natural gas plant on an American Indian reservation.
  • Represented a major national resource company in obtaining the permit to construct a dam and hydropower facility.

  • Represented a public utility in the negotiations with an American Indian tribe to explore for coal on the Indian reservation.

Environmental Litigation
  • Defended the state and federal permits granted to a major U.S. natural gas company for the construction of a natural gas pipeline in the 9th Circuit Court of Appeals.
  • Represented a major U.S. natural gas pipeline operation in suing the federal government over the clean-up of uranium tailings on an American Indian reservation.
  • Represented a major U.S. natural gas pipeline operation in defending a class action lawsuit brought by individual tribal members claiming the amount of right-of-way lease payments were deficient.
  • Part of a litigation team that successfully represented Pennsylvania Power and Light before the United States Supreme Court in overturning a Montana Supreme Court decision concerning the ownership of riverbeds within the state.

  • Represented a public utility in negotiations with an American Indian tribe to explore for coal on the tribe’s reservation.

Representation of Clients before Federal and State Agencies and Congress

  • Represented a regional public utility before the EPA on issues relating to the Clean Air Act.

  • Represented trona and coal companies on regulatory matters before the Department of the Interior.
  • Represented various entities in dealing with the intricacies of the Indian Regulatory Gaming Act and the Bureau of Indian Affairs.
  • Represented both companies and ranchers on clarifying their water rights in western states.
  • Represented a large charitable trust health group in obtaining funding to improve and increase FDA inspections for imported foods.
PRACTICES

Practices

American Indian Law
Government Investigations and White Collar Defense
Endangered Species and Wildlife Regulation
Environmental and Natural Resources Litigation
Water Law
Environmental and Natural Resources
NEWS AND INSIGHTS

News

Speaking Engagements

"Clinton, Bush, and Obama: A Panel Discussion with the Justice Department's Environmental Leaders for Three Presidents," 2016-2017 University of Michigan Environmental Law and Policy Program Lecture Series, Panelist, September 2016
"Looking Ahead to the Next Administration: Who Will Decide Policy on Energy, Environment & Legal Issues?," EnviroFest 2016 - "The Political Economy of the Environment", October 2016
"Representing Clients Before Federal Agencies," Washington and Lee University School of Law, April 2014
"An Update on Energy/Natural Resource Issues of Interest," 2016 University of Wyoming Landscape Discussion on Energy Law & Policy in the Rockies, October 2016
"Looking Ahead to the Next Administration," Independent Petroleum Association of America Mid-Year Meeting, July 2016
"The legal and policy aspects of renewables project development in California," Federalist Society event at Stanford Law School, Panelist, January 14, 2015
EDUCATION AND ADMISSIONS

Education

Washington & Lee University
J.D., 1976
University of Virginia, Colgate Darden School
M.B.A., 1973
University of Virginia
B.A., 1971
  • Foreign Affairs, With Distinction

Bar Admissions

Colorado
District of Columbia
Wyoming

Court Admissions

U.S. Supreme Court
U.S. Circuit of Appeals for the D.C., Federal, First, Second, Eighth, Ninth, and Tenth Circuits
RECOGNITION

Recognition

  • Chambers USA: America’s Leading Lawyers for Business, Native American Law, Nationwide, 2012-2019
  • American College of Environmental Lawyers, Fellow, 2012-Present
  • The Best Lawyers in America© Lawyer of the Year, Environmental Law – Cheyenne, 2016
  • The Best Lawyers in America© Lawyer of the Year, Government Relations Practice – Cheyenne, 2012, 2015, 2017
  • The Best Lawyers in America© Environmental Law, Government Relations Practice, Native American Law, 2007-2020; Oil and Gas Law, 2018-2020
  • Mountain States Super Lawyers®, Energy & Resources, 2011-2019
  • Mountain States Super Lawyers®, "Top 100 Lawyers," 2018
  • Denver Business Journal, Who’s Who in Energy, 2012-2013
PROFESSIONAL AND CIVIC AFFILIATIONS

Professional and Civic Affiliations

  • Washington & Lee University School of Law, Member, Law Council, 2011-Present
  • University of Denver Sturm College of Law, Natural Resources Law, 2012 Practitioner in Residence
  • United States Commission on Civil Rights for the State of Wyoming, Chairman, 2008-2012
  • Republican National Committee, General Counsel, 2001
  • Wyoming's Republican National Committeeman, 1996-2001
  • Wyoming Republican Party, Chairman, 1983-1987
DISCLAIMER

Unless you are a current client of Holland & Hart LLP, please do not send any confidential information by email. If you are not a current client and send an email to an individual at Holland & Hart LLP, you acknowledge that we have no obligation to maintain the confidentiality of any information you submit to us, unless we have already agreed to represent you or we later agree to do so. Thus, we may represent a party adverse to you, even if the information you submit to us could be used against you in a matter, and even if you submitted it in a good faith effort to retain us.

Accept
Decline