Knows the hazardous waste law and regulations in California better than anyone.
The Legal 500 U.S.

Margaret Rosegay is a leading environmental lawyer with nearly four decades of experience addressing solid and hazardous waste regulations and water quality issues.

Meg advises on state and federal environmental regulations and compliance; provides guidance on upstream oil and gas exploration, refining and production issues; handles RCRA corrective actions, NPDES permitting and Clean Water Act matters; and conducts environmental impact analysis. Advising on environmental aspects of transactions, Meg oversees due diligence and drafts and negotiates environmental disclosures, representations and warranties. She also provides project planning counsel. A registered California lobbyist, Meg helps shape environmental laws and policies.

Representative Experience

  • Negotiated a favorable settlement for an environmental services company in a federal EPA administrative enforcement action regarding implementation of an RCRA land disposal restrictions program.
  • Defended an oil and gas industry trade association in litigation brought by NGOs challenging ongoing production operations, including underground injection, hydraulic fracturing and well permitting.
  • Represented an electrical generating entity in a multi-year process to decommission and remove a natural gas-fired power plant; work encompassed interpretation of contracts and all other environmental aspects of project.

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  • Resolution of significant contractual dispute relating to allocation of environmental liabilities associated with the sale of a petroleum refinery
  • Representation of major real estate developer in connection with former industrial complex undergoing "brownfields" redevelopment
  • Successful administrative challenge to NPDES permit conditions imposed by a regional water quality control board and the Environmental Protection Agency prior to the development of TMDLs
  • Defense of several major hazardous waste enforcement actions brought by the Department of Toxic Substances Control
  • Successful mediation and consummation of a cash-out settlement agreement in connection with one of the operable units within the San Gabriel Valley Superfund Site

Professional Highlights

  • Recognized by Chambers USA for Environment – California (2007–2019); Best Lawyers (published by BL Rankings LLC) for Environmental Law, Litigation – Environmental (2006–2020); and The Legal 500 U.S. for Energy – Renewable/Alternative (2016) and Environment (2016, 2018-2019).
  • Named to BTI’s “Client All-Stars” list in 2015 and 2016.
  • Authored California Hazardous Waste Management, published by California Environmental Publications.

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  • Honors & Awards
    • Who's Who Legal, Environment—San Francisco (2010)
    • Middle-Market M&A Award, Consumer and Retail Products—Finalist, M&A Advisor (2008)
  • Associations
    • American Bar Association (Natural Resources section)
    • Air and Waste Management Association
    • San Francisco Bar Association 


  • J.D., University of Colorado, School of Law, 1980
    Clerk, Colorado Court of Appeals

    A.B., University of California, Berkeley, 1972


  • California


  • Clerk, Colorado Court of Appeals