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Jonathan Welner

Jonathan Welner

also known as Jon Welner

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About Me

Jon Welner is a leading practitioner of environmental and natural resource law in California. Jon represents clients in all areas of environmental, natural resource, and land use law. His practice includes the regulation of air, water, hazardous substances, hazardous waste, radiological materials, development of contaminated properties (“Brownfields”), energy and water companies, coastal development, endangered species and other natural resources, as well as matters involving CEQA and NEPA (environmental impact reports/studies), the Williamson Act (farmland preservation), and Prop 65. He has special expertise in conducting legal audits and developing compliance systems, and in the early transfer and redevelopment of former military bases. Jon is frequently called upon by the media to comment on environmental and natural resource topics.

Jon is also the Chair of JMBM’s Prevailing Wage Practice Group. He is recognized as one of the foremost practitioners in the State, and is frequently involved in complex and groundbreaking cases on behalf of developers, contractors, and manufacturers. Jon has been featured in the California Lawyer as one of top prevailing wage lawyers in the State.

Jon represents clients in both administrative and judicial proceedings, including proceedings before California Air Districts, the State and Regional Water Boards, the California Department of Toxic Substances Control, the California Department of Public Health, the California Department of Conservation,the California Public Utilities Commission, the California Energy Commission, the Coastal Commission, the San Francisco Bay Area Conservation and Development Commission (BCDC), the State Lands Commission, the California Department of Industrial Relations, U.S. EPA, the U.S. Army Corps of Engineers, the U.S. Nuclear Regulatory Commission, the U.S. Department of Labor, local governments, and other agencies. He has previously served as a senior official at the California Natural Resources Agency.

Jon's clients include project developers, land owners, renewable energy companies, hospitality companies, water utilities, automobile manufacturers, chemical manufacturers, biotechnology companies, modular building manufacturers, scrap metal recyclers, hazardous waste and solid waste landfills, local governments, and nonprofit organizations.

Jon Welner is Chair of the Planning Commission of the Town of Tiburon, California.


Languages Spoken: English, Hebrew

Photos and Videos

245371 1329031603

Practice Areas


  1. Employment & Labor: 50%
    13 years, 30 cases
  2. Environmental and Natural Resources: 50%
    20 years, 100 cases

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Contact Info

Jeffer Mangels Butler & Mitchell LLP

Two Embarcadero Center
Fifth Floor
San Francisco, CA, 94111



Professional Misconduct

We have not found any instances of professional misconduct for this lawyer.
Avvo Contributions
Legal Answers
Award NameGrantorDate Granted
Best Lawyers in America, Environmental LitigationBest Lawyers in America2016
Martindale-Hubbell Peer Review, AV Preeminent, 5.0 out of 5.0Martindale-Hubbell2013
Associate EditorStanford Law Review1993
John Gardner FellowshipStanford University1989
MemberPhi Beta Kappa1988
Harry S. Truman ScholarshipHarry S. Truman Scholarship Foundation1987
Work Experience
TitleCompany NameDuration
PartnerJeffer Mangels Butler & Mitchell LLP2012 - Present
PartnerDowney Brand LLP2010 - 2012
Of CounselPaul Hastings Janofksy & Walker, LLP2002 - 2010
ConsultantMcKinsey & Company2000 - 2002
AttorneyBeveridge & Diamond, PC1996 - 1999
ClerkU.S. District Court (N.D. Cal.)1995 - 1996
Association NamePosition NameDuration
State Bar of California, Environmental Law SectionMember, Executive Committee2014 - Present
Planning Commission, Town of TiburonChair2012 - Present
Bar Association of San Francisco, Environmental Law SectionImmediate Past Chair2010 - Present
Legal Cases
Case NameOutcome
Prevailing wage lawsuitVery favorable settlement
McClellan Air Force Base "Early Transfer"Successful transfer
See all Legal Cases 
School NameMajorDegreeGraduated
Stanford Univ Law SchoolN/AJ.D.1995
Stanford UnivPolitical ScienceA.B.1989
Speaking Engagements
Conference NameTitleDate
Prevailing Wage in California (Santa Rosa)Prevailing Wage in California2014
Prevailing Wage in California (San Francisco)Prevailing Wage in California2014
Prevailing Wage in California (Sacramento)Prevailing Wage in California2014
Prevailing Wage in California (Milpitas)Prevailing Wage in California2014
Prevailing Wage in California (Sacramento)Prevailing Wage in California2013
Bar Association of San Francisco PanelWhat the Frack? The Growth and Regulation of Hydraulic Fracturing in California2013
Bar Association of San Francisco PanelSolar & Wind Power vs. Farmland: The New Battleground?2012
Prevailing Wage in California (San Jose)Prevailing Wage in California2011
Prevailing Wage in California (Oakland)Prevailing Wage in California2011
Prevailing Wage in California (Monterey)Prevailing Wage in California2011
Bar Association of San Francisco PanelBCDC’s Climate Change Proposal: Good Policy or “Power Grab”?2011