Michelle N. O'Brien

Michelle O'Brien handles environmental and land use permitting and related litigation for various types of developments including residential homes, commercial buildings, waterfront properties, and solid waste facilities. She has more than 30 years of experience in public and private practice. Michelle frequently defends companies in environmental enforcement matters at the federal, state, and local levels, bringing her experience as a government lawyer to bear. She represents private parties in cost recovery and property damage claims involving releases of oil and hazardous materials, and assists companies with regulatory compliance under cleanup laws. Michelle also assists clients with real estate transactions involving contaminated properties and other environmental issues. She often conducts environmental due diligence for real estate and business transactions, including the financing and development of renewable energy facilities such as battery energy storage systems and solar farms.

An accomplished litigator, Michelle obtained one of Massachusetts' highest trial verdicts in 2005. She has also appeared before the Massachusetts Appeals Court several times, and in 2014 obtained a victory before the Supreme Judicial Court in a case of first impression.

Before joining Pierce Atwood, Michelle practiced 15 years at the boutique environmental law firm Mackie Shea O’Brien, PC (formerly known as Moehrke ,Mackie & Shea). Prior to that she was a Massachusetts Assistant Attorney General in the Environmental Protection Division, where she brought cost recovery and enforcement actions under M.G.L. Chapter 21E, and the Trial Division, where she represented state agencies and employees in state and federal court litigation. She was a law clerk to the Justices of the Massachusetts Superior Court and a legislative aide to the Chair of the Massachusetts Legislature's Committee on Natural Resources and Agriculture.

Chambers USA, publishers of America’s Leading Lawyers for Business, quoted one impressed commentator as saying, "She has lots of professional judgment, is well connected, and handles landmark environmental cases - she's an excellent professional."

Honors & Distinctions
  • Recognized for Environmental Law by  Lexology's "Who's Who Legal" (2023-present)
  • Recognized by Super Lawyers as one of the Top 50 Women Attorneys in Massachusetts (2019)
  • Named to Massachusetts Lawyers Weekly "Top Women of Law" List (2015)
  • Included in the Bar Register of Preeminent Women Lawyers (2011-present)
  • Recognized by Chambers USA for Environmental Law (2007-present)
  • Recognized by The Best Lawyers in America® for Environmental Law and Litigation - Environmental (2006–present)
  • Recognized as a "Massachusetts Super Lawyer" in environmental law (2006–present)
  • Received the LSP Association Member Award for contributions to the practice (2007)
  • Received the Lesley University Alumni Achievement Award (2004)
Professional Activities
  • Member, New England Women in Energy and Environment (2016-present)
  • Member, NAIOP Massachusetts (2018-present)
  • Member, Board of Directors, Environmental Business Council of New England (EBC) (2016-present)
  • Leadership team, EBC Site Remediation & Redevelopment Committee (2016-present)
  • Clerk, EBC (2022-present)
  • Member (selected by the Boston Bar Association executive director), Supreme Judicial Court’s Lawyer Mentoring Program Working Group (2019)
  • Appointed member, MassDEP’s Waste Site Cleanup Advisory Committee (2008-present)
  • Elected member, Boston Bar Association (BBA) Council (2009-2012)
  • Co-chair, BBA Environmental Sustainability Task Force (2011-2012)
  • Co-chair, BBA Environmental Law Section (2006-2008)
  • Associate member, LSP Association (2002-present)
  • Member, CREW Boston (formerly known as New England Women in Real Estate) (2011-2018)
  • Founding member, Massachusetts Chapter of the Society for Women Environmental Professionals
Civic Activities
  • Member, Lesley University Board of Trustees (2010-2022)
  • President, Lesley University Alumni Association (1998-2002)
  • Chair, Lesley University Presidential Search Committee (2018-2019)
  • Co-chair, Lesley University Centennial Steering Committee (2009-2010)
  • Former Planning Board Vice-Chair

Practice Areas

Representative Experience
  • Representing potentially responsible party for Massachusetts Superfund site
  • Advised solid waste company in local and state permitting processes and business considerations for potential development of new Massachusetts facilities
  • Represented small business owner in defense and resolution of federal and state cost recovery and enforcement actions involving asbestos in demolition material at proposed residential development site
  • Assisting owner of large brownfields site with regulatory compliance and development considerations for addressing newly-discovered contamination
  • Represented owner of solid waste facility in local permitting for major landfill expansion
  • Assisting successor company to munitions manufacturer with regulatory compliance and cleanup cost allocation for large site involving buried munitions and mercury contamination primarily in sediments
  • Defended national company and resolved enforcement action brought by the U.S. Environmental Protection Agency under the Emergency Planning and Community Right-to-Know Act concerning two New England facilities
  • Representing property owner in pursuit of final cleanup and cost recovery for commercial and residential properties affected by volatile organic compound contamination in groundwater and indoor air
  • Represented client in enforcement action brought by state environmental agency alleging violations of odor regulations at the client’s petroleum bulk storage and distribution facility
  • Represented client in successful termination of 30-year-old consent decree with state and federal environmental agencies
  • Assisting owner of commercial shopping plaza with regulatory compliance in connection with groundwater contamination from a former dry cleaning operation located in the plaza
  • Assisted technology-leading specialty color supplier to plastics processors with compliance evaluation and modification of air pollution control permit for a manufacturing facility in Massachusetts
  • Representing owners of closed landfills with regulatory compliance and potential post-closure uses, including ground-mounted solar
Representative Experience
  • Advised client with regard to water rights in river abutting residential property
  • Represented developer of oceanfront residential property in appeals of denial of permits under state and local wetlands laws for construction of a replacement home and new septic system
  • Assisted company with environmental diligence prior to the acquisition of a former landfill and surrounding property, including evaluation of available environmental insurance products
  • Represented developer of small residential subdivision in permitting and appeals under state and local wetlands laws
  • Assisted developer of suburban residential subdivision with completion of remediation of historic contamination and securing permit to traverse state-owned land
Representative Experience
  • Representing residential property owner in lawsuit seeking cost recovery, property damages, and tort damages in connection with fuel oil spill in basement of building
  • Represented municipality in successful defense of waterfront property owner’s claim for regulatory taking, including trial and appeals in state court and owner’s unsuccessful request for U.S. Supreme Court review
  • Successfully represented developer/buyer of vacant land for proposed residential subdivision in decade-long litigation with sellers regarding their failure to comply with purchase and sale agreement, including state court trial, appeals to Massachusetts Appeals Court and Supreme Judicial Court, additional state court proceedings, and successful second appeal to Massachusetts Appeals Court
  • Defended federal enforcement action alleging violations of the Clean Water Act at a cranberry farm, including jury trial and negotiation of consent decree governing mitigation
Representative Experience
  • Assisting financiers of portfolios of proposed battery energy storage system projects with environmental and permitting diligence
  • Assisted multiple developers of proposed battery energy storage system projects with environmental, land use, and permitting diligence on potential project sites
  • Assisted potential investors and project teams in conducting environmental and land use due diligence for development of ground-mounted solar projects
  • Represented owner of closed landfill in negotiation of agreements for solar development