Dean S. Sommer

phone (518) 438-9907 (Ext. 236)
fax (518) 438-9914
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Dean S. Sommer (Senior Partner) concentrates on the litigation and/or negotiation of environmental and toxic tort matters addressing the release of hazardous substances, hazardous waste, petroleum and solid waste into the environment. Mr. Sommer has been listed by Chambers USA in the top ten of New York environmental attorneys since 2003 and among the top six “Leading Individuals” in environmental law in New York since 2011.  Chambers USA, in its 2004 Guide, stated that Mr. Sommer is “a noted litigator” whose “expertise is on show in Superfund, RCRA and CWA issues.” In 2005 Chambers USA noted that “the first name on the lips of commentators was that of ‘innovative’ Dean Sommer, who stands out for his ‘completely refreshing approach.’”  Chambers USA, in its 2016 Guide notes Mr. Sommer as “a very smart guy” who is “known for his cleanup, brownfields and toxic tort work” and whose “experience encompasses petroleum spills, solid and hazardous waste and the release of hazardous substances.” In 2015, its Guide notes that Mr. Sommer is “a very bright and creative lawyer” and “is highly regarded for his litigation expertise.” In 2013, Chambers quotes clients as referring to Dean as “absolutely brilliant”. His clients include a mix of industry, municipalities and brownfield developers and he provides both defense and plaintiff litigation services. In its 2012, 2013, 2015 and 2016 Guides, Young/Sommer is also listed as one of the leading environmental firms (Bands 2 and 3) in New York State. Dean has been counsel for several brownfield projects throughout the Hudson Valley and Capitol District regions. He has significant “risk communication” and real estate due diligence experience. Dean served as Section Chief of the Toxics Enforcement Unit in the Albany office of the State Attorney General’s Office from 1983 until 1995. He served as a member of the transition team for Attorney General Eliot Spitzer in 1998. As an Assistant Attorney General, he was either the lead attorney or the supervising attorney on dozens of CERCLA, RCRA and CWA cases.

Bar Admissions

New York, 1979
U.S. District Court Northern District of New York, 1979
U.S. District Court Western District of New York, 1979
U.S. District Court Southern District of New York, 1995
U.S. District Court Eastern District of New York, 2004
U.S. Court of Appeals 2nd Circuit


Georgetown University Law Center, Washington, District of Columbia
Juris Doctor

Washington University, St. Louis, MO
Honors: Summa Cum Laude
Honors: Undergraduate Teaching Assistant
Major: Philosophy

Published Works

Article XIV Citizen’s Suits in Federal Court Recognized by Appellate Division, New York State Bar Association, The New York Environmental Lawyer, Spring/Summer, 2000

Emissions Trading Under the Clean Air Act, Capital District Business Review, Spring, 1999

Credibility and Cost Containment Through Communication, Environmental Business Association of New York State, Inc. Environmental Business Update, Second Quarter Issue, 1997

Working with Consultants, Environmental Due Diligence in Real Estate and Commercial Transactions, May 15, 1997

The Challenge of Contaminated Properties: Potential Liabilities and Creative Approaches to Problems They Pose, New York State Bar Association-Environmental Law Section and Municipal Law Section, September, 1996

Public Pollution/Public Resolution, National Environmental Enforcement Journal, August, 1995

Electro-Magnetic Fields: Public Concern, National Environmental Enforcement Journal, May, 1994

Beyond Compliance Enforcement, National Environmental Enforcement Journal, March, 1993

Using Federal Civil RICO Against Outlaw Waste Haulers, National Environmental Enforcement Journal, October, 1992

Classes/Seminars Taught

2013 New York State Department of Environmental Conservation Brownfield Cleanup Program Session

2011 New York State Department of Environmental Conservation Brownfield Cleanup Program Session

Moving the Process Along, New York State Brownfield Coalition Brownfield Seminar, October 2010

The Redevelopment of Contaminated Property: New York State’s Brownfield Program and Beyond, New York State Bar Association Seminar June 2009

Joint Prosecution Agreements Between the State and Indian Nations, Conference on the Environment and Native Americans in New York State, 2000

Legal Implications of EPA Inspections in the Academic Environment, Environment 2000 Summit SUNY Environmental Health and Safety Association, 2000

CERCLA Contribution Claims After Bedford Affiliates v. Sills, New York State Bar Association, Environmental Law CLE, 2000

Creative Approaches to Contaminated Property, New York State Bar Association, Environmental and Municipal Law Section, 1996

Land Use Environmental Mediation, 8th New York State National Conference on Dispute Resolution, Saratoga Springs, NY, 1996

Brownfields in the Greenway: Public Participation, Greenway Council, 1996

Hazardous Waste Clean-up in New York, Government Institutes – New York Environmental Law, 1996

Brownfields – Legal Requirements, Northern New York Associated Environmental Technologies Conference, 1996

Environmental Law for Engineers: Pollution & Risk Communication, Rensselaer Polytechnic Institute, 1995

Environmental Negotiation, Mediation and Enforcement, Bard College, 1995

Honors and Awards

Conservationist of the Year, Brewster Land Conservancy Trust, Brewster, MA, 1996
New York State Disaster Preparedness Commission, 1990
City of Cortland, New York, 1989
Appointment to transition Team for Eliot Spitzer, Attorney General, State of New York, 1998
Brownfield Working Group for 2006 Transition Team for Governor – Elect Eliot Spitzer, 2006
Listed as Top Environmental Lawyer in New York Super Lawyers – Upstate Edition, 2007, 2008 and 2009
Listed in The Best Lawyers in America®, 2007, 2008 and 2010
Listed in Cambridge Who’s Who of Executives and Professionals, 2011
Listed in Chambers USA as one of the top ten of New York environmental attorneys, 2003 – 2023
Listed in Chambers USA among the top four “Leading Individuals” in environmental law in New York, 2011 – 2023
Listed as a 2013 Top Rated Lawyer in Energy/Environmental by American Lawyer Media and Martindale-Hubbell™
Listed in Law Business Research Ltd. Who’s Who Legal Environment, 2017
Listed as Best Lawyer in America (Environmental Law) by U.S. News – Best Lawyers®, 2018-2023

Professional Associations and Memberships

New York State Bar Association, Environmental Law Section, 1999 – Present

Legal Assistant Information

Brittany Bardin, 518-438-9907 x. 277