David J. Armstrong


Tel 602.798.5412
Fax 602.798.5595

David J. Armstrong counsels clients on environmental risks and liabilities in corporate and real estate transactions and regulatory compliance. David has significant experience assisting clients in the defense of administrative and civil proceedings involving permitting and environmental enforcement matters at the federal and state levels. He also has experience conducting environmental due diligence, negotiating environmental indemnity agreements and environmental insurance policies, and providing advice on environmental issues in a variety of transactions.

David regularly litigates environmental matters for industrial, manufacturing, and commercial clients across the country in federal and state courts, in administrative tribunals, and before arbitrators and mediators.

Representative Matters

Enforcement and Litigation

  • Represents a property owner in environmental litigation against a manufacturing tenant that caused substantial contamination of property near Reno, Nevada
  • Represents a regional convenience store chain in defense of a RCRA 7003 Order issued by the federal Environmental Protection Agency and federal, state, and tribal court litigation related to that order
  • Serves as lead counsel for an Arizona utility in the defense of a $40 million federal Superfund claim for alleged groundwater contamination in metropolitan Phoenix
  • Represented a pre-school in claims associated with the presence of environmental contaminants
  • Successfully defended a national nursery chain against federal Superfund claims associated with contaminated property located in Northern California
  • Successfully resolved two separate administrative proceedings initiated by the Arizona Department of Environmental Quality against a Utah-based convenience store chain concerning remediation of leaking underground storage tanks
  • Successfully represented a Fortune 100 company in defeating an environmental tariff proposed by the Colorado Public Utility Commission
  • Served as expert witness in Nevada state court action interpreting contract and Lincoln County regulations in terminated solar power deal
  • Won substantial damages (including past costs, attorneys' fees, pre-judgment interest, and future remedial costs) in an arbitration case against an environmental consultant for breach of contract and negligence
  • Won a full defense verdict for a major petroleum products distributor following a three-week jury trial in Arizona state court where the plaintiff was asking for $14 million in damages in connection with the alleged migration of petroleum hydrocarbons
  • Successfully represented an international mining client in several mediations concerning allocation of liability to resolve federal Superfund claims
  • Initiated and won a case against a client's tenant for causing significant environmental contamination of the client's property
  • Successfully settled a multimillion-dollar Oil Pollution Act and natural resource damage claim asserted by the Department of Interior against a national petroleum distributor
  • Represented clients in federal Superfund litigation matters in Arizona, California, Oregon, Missouri, New York, New Jersey, and Pennsylvania

Compliance and Permitting

  • Successfully assisted an Eastern Arizona biomass facility in connection with renewal of its Class I air quality permit
  • Assisted a Nevada company in effectuating environmental permit transfers in connection with the sale of the company
  • Prepared detailed comments on proposed water quality permit associated with a Mesa, Arizona, facility
  • Counseled a client in permitting issues associated with development of a potash mine in Utah
  • Assisted a national home builder in obtaining water quality permit and case closure for alleged discharge violations
  • Successfully represented a regional petroleum products distributor in obtaining renewal of air quality permit
  • Assisted wind-powered electric generating facility with securing permit to construct under Nevada Utility Environmental Protection Act
  • Successfully represented an international aviation company in avoiding significant penalties associated with its past hazardous waste disposal practices
  • Successfully resolved notices of violations issued to an Arizona biomass facility for alleged air quality permit violations
  • Successfully defended clients' hazardous waste and water quality permits in challenges by environmental groups before administrative tribunals and appellate courts
  • Successfully negotiated compliance orders, consent judgments, and decrees with state and federal environmental agencies on behalf of industrial clients
  • Successfully settled notices of violations for alleged air quality violations by a national home builder
  • Assisted an international aviation company in establishing an environmental compliance program
  • Successfully represented a regional pool company in obtaining "no further action" letter from the Arizona Department of Environmental Quality in connection with the cleanup of former leaking underground storage tank site
  • Represented a hazardous waste storage facility in connection with an order revoking the company's hazardous waste permit for alleged statutory and regulatory violations


  • Assisted an international aggregate company in performing environmental due diligence, including permit transfers, in connection with its purchase of 22 facilities in the Midwest and Southeast United States
  • Represented lender in foreclosing on contaminated parcel in Las Vegas
  • Assisted a major distributor of electronic components in performing environmental due diligence in connection with its purchase of electronic recycling facilities in Texas, Ohio, and Georgia
  • Provided environmental counsel to a major bond underwriting company on environmental risks and liabilities associated with underwriting bonds for Arizona Charter school
  • Assisted an international energy company in analyzing environmental risks associated with its purchase of oil and gas facilities in Texas and Louisiana
  • Routinely assists a national automobile dealership in performing environmental due diligence in connection with its purchase and sale of dealership facilities
  • Performed environmental due diligence and lead team effectuating permit transfers in connection with the purchase of a mine in Southeastern Utah
  • Assisted a major East Coast utility in performing environmental due diligence associated with its purchase of interests in Arizona and California solar facilities
  • Assisted a national solid waste collection company in performing environmental due diligence associated with its acquisitions and divestitures nationwide
  • Performed environmental due diligence for a private equity firm in connection with its purchase of a biomass facility in Arizona
  • Drafted and negotiated the environmental provisions of a purchase and sale agreement in a $312 million Arizona real estate deal on behalf of a national home builder
  • Provided environmental counsel and drafted and negotiated environmental provisions of sale or lease agreements on behalf of an international mining client in more than 50 real estate deals
  • Negotiated numerous environmental insurance policies for clients, including a $50 million cost cap and pollution legal liability policy

Professional Activities

State Bar of Arizona
Member, Environmental and Natural Resources Law Section

Arizona Forward, Member

Recognition & Accomplishments

Chambers USA, environment (including water rights), 2013-2020

The Best Lawyers in America, environmental law, 2013-2021

The Legal 500 US, energy – renewable/alternative, 2014-2015

Named to Who's Who Legal: Environment, 2012, 2014, 2015, 2019, 2020

Board Memberships

Association of Arizona Food Banks, Chairman of the Board

Arizona Petroleum Marketers Association, Member, Board of Directors

Temple University James E. Beasley School of Law (J.D. 1992)
Editor-in-Chief, Temple Environmental Law & Technology Journal; Recipient, Barrister Award for Trial Advocacy

College of Charleston (B.A. 1985)



U.S. District Court for the District of Arizona

U.S. District Court for the District of New Jersey

U.S. District Court for the Eastern District of Pennsylvania

U.S. Court of Appeals for the Ninth Circuit

Federal courts in Connecticut, Nevada, New York, and Oregon and the Navajo Nation Tribal Court (admitted pro hac vice)