Loren R. Dunn,





Loren is a senior member of the Environmental Law practice group. He practices in the environmental law and litigation fields, and represents regional and national companies at locations throughout the country.

Loren’s environmental projects have involved hazardous waste and large multi-party toxics cleanup sites, including marine and fresh water sediment sites, landfills, and natural resource damages claims. He has also conducted extensive work obtaining permits for key facility operations. He has particularly deep knowledge of the following industries: manufactured gas facilities, regulated utilities, smelters and metals refineries, pesticide sites, and large area contamination sites.

Before entering private practice, Loren worked for the U.S. Environmental Protection Agency headquarters office as a senior policy economist. He received an agency merit award for excellent work on the development of the Agency’s hazardous waste program and its regulations.

Loren has been repeatedly recognized as one of the leading environmental lawyers in the Northwest. He is a respected leader in handling complex environmental litigation, and remediation and restoration projects under CERCLA and state “little Superfund” statutes. He helped to pioneer the successful use of technical, large-group mediation to secure more efficient resolution and cleanup of large sites impaired by hazardous substance releases. He is co-chair of the ADR process of Portland Harbor – the largest Superfund site west of the Mississippi. He also has played a significant role in the development of Washington’s environmental regulatory system.

Representative Matters – Environmental Projects

  • Counsel to international nuclear engineering and construction firm. Provided advice and assistance regarding design, construction, and permitting of proposed nuclear waste treatment facility, including clean air and waste management permits.
  • Counsel to Fortune 500 investor-owned utility. Provided advice and assistance, including litigation defense, concerning remediation of multiple hazardous waste sites. Work has included lead role in organizing, developing, and managing multi-party arbitration and follow-up mediation for dividing clean-up costs at an 80+ party urban Superfund sediment site. Negotiated performance consent decree settlement with EPA. Assisted in development and implementation of innovative, cost-effective remedy for aquatic sediment site. Negotiated cash-out settlement with 80+ responsible parties, and cost-sharing settlements with other major performing parties. Pursuing ongoing cost recovery actions against recalcitrant parties. Assisted in securing orphan status designation for chemical manufacturing site wrongfully attributed to client. Prompted grant of public funding for cost of clean-up of site.
  • Represented major municipality in a variety of environmental matters, including defense and enforcement of hazardous substance cleanup actions and land use and boundary adjustment matters.
  • Counsel to major international paper company. Provided advice and assistance regarding property acquisition, leasing, and due diligence advice, clean water act permitting, compliance, and enforcement actions, defense of citizen suits, hazardous waste and asbestos compliance assistance, remediation of contaminated sediments, air emissions permitting, landfill permitting, and advice regarding potential natural resource damages claims.
  • Counsel to nation’s largest producer of building and packaging materials made from polystyrene insulating foam. Representation has included providing assistance in negotiating air quality emissions permits and settlement of local and regional air authority enforcement actions, pursuit of cost recovery litigation involving the failure of purchased air quality control and process efficiency equipment, and defense of cleanup cost recovery and contribution actions and natural resource damages cost recovery claims at Superfund sediment mega-site.
  • Counsel to international nuclear engineering and construction firm. Provided advice and assistance regarding design, construction, and permitting of proposed nuclear waste treatment facility, including clean air and waste management permits.
  • Counsel to Fortune 500 metals manufacturing company on hazardous waste compliance issues, including handling citizens’ suit regarding waste disposal practices, clean air act permitting, and federal litigation challenging hazardous waste disposal and recycling regulations.
  • Assisted with site review, facility siting and acquisition, site remediation, and permitting of new brewery facility for national specialty beer brewer.
  • Counsel to leading cooperatively owned manufacturer of fine wooden building and construction materials. Assisted with site cleanup, shoreline permitting, site development activities, and defense of federal contaminated sediment cleanup and cost recovery claims at Superfund mega-site. Lead negotiator for securing consent decree for 25+ cash-out parties for major multi-party federal Superfund site. Lead negotiator in responding to multi-party natural resources damages recovery claims brought by federal, state, and tribal trustees. Responsible for design and management of multi-party mediation process for resolving trustees’ claims.
  • Counsel to family held regional machine manufacturing company. Provided assistance regarding hazardous waste compliance issues, storm water discharge permitting, sale of manufacturing facilities, defense of multi-party contribution and cost recovery claims relating to on-site and maritime sediment contamination cleanup, settlement of natural resource damages liabilities, consent decree negotiations with federal regulatory agencies, and insurance recovery negotiations.
  • Counsel to small municipality in pursuing cost recovery and replacement of critical drinking water wells contaminated by releases of hazardous substances to groundwater from regional landfill.
  • Counsel to one of largest national parking service companies in defense of multi-million-dollar hazardous substance contribution claims resulting from contamination releases affecting two high-rise office towers.
  • Counsel to northwest’s largest manufacturer of brick and concrete building materials.
  • Representation included clean air act permitting and defense of air quality enforcement actions, assistance with hazardous substance remediation activities and defense of related enforcement actions, and defense of litigation involving property adversely affected by hazardous substance releases.
  • Assisted with environmental analysis and site cleanup for regional casting and machining plant for Fortune 500 international tool and die, casting, and machining company.
  • General counsel to one of nation’s leading environmental toxicology consulting firms. Provide advice on environmental contracting and regulations. Prosecuted claims involving employee termination, unfair competition, and embezzlement.
  • Represented EPA remedial action construction contractor in defending claims by property owner for contribution for costs of conducting EPA emergency removal action at pesticide-contaminated hop farm.
  • Represented owner of wood treatment facility in defense of claims by EPA for recovery of costs incurred by EPA in performing time-critical emergency removal action. Negotiated advantageous site clean-up performance consent decree with EPA.
  • Counsel to major regional electric utility in preparing defense to contribution, cost recovery, and natural resource damages claims at Superfund sediment mega-site.
  • Counsel to leading northwest automotive distributor and automotive services provider.
  • Assisted with hazardous waste management, clean water permitting, EPA and FAA enforcement matters, and environmental cleanup contribution litigation.
  • Provided representation for major clothing manufacturer in defending clean water act enforcement action and in negotiating for issuance of clean water permit.
  • Represented national food manufacturer in defending enforcement action for exceedances of waste water discharge permit.
  • Served as lead environmental counsel in defense of toxic tort class action brought by residents of mobile home park against multiple parties responsible for past and currently operating landfill.
  • Assisted local specialty coffee roaster in resolving claims related to air emissions from nearby metals coating and spray painting operation.
  • Counsel to Fortune 500 chemical manufacturing company in resolving multi-party cost recovery litigation relating to the cleanup of historic explosives manufacturing facility.
  • Represented regional landfill owner and operator in regulatory agency negotiations for closure plan and remedial implementation.
  • Counsel to nation’s leading photo safari touring company in seeking to recover for damages to property due to illegal disposal of waste materials, and in responding to slanderous Internet communications from world-wide environmental organization relating to company’s business practices.
  • Defended multiple owners/operators of past automotive service stations in cost recovery contribution actions arising from underground storage tank releases.
  • Lead environmental counsel in multiple large class actions against international metals smelters and metals manufacturing facilities.
  • Represented major oil company in defense of multi-party hazardous substance cleanup contribution action involving releases from metal mining and smelting operation in British Columbia.
  • Provided permitting assistance for facility siting of experimental design and testing facility for electrical generation company, including air emissions and local development permits.
  • Represented numerous multi-family residential complexes in cases involving environmental hazards and contamination caused by federal Superfund site. Cases involved issues of trespass, nuisance, inverse condemnation, groundwater contamination, underground migration of landfill gases, and land use and landfill permitting and compliance issues. Successfully overturned proposed federal consent decree that inadequately protected adjacent property owners.
  • Provided environmental regulatory compliance assistance to international manufacturer of clothing and footwear.
  • Defended past private landowner against $50 million claim for costs of site remediation due to releases of petroleum contamination from series of oil pipelines.

Representative Matters – Commercial and Technology Litigation Projects

  • Represented international manufacturer of enterprise resource planning software in defense of multiple cases alleging sale of defective software and/or misrepresentation in the sale of software.
  • Assisted west coast package delivery company in resolving claims for loses due to failed installation of integrated billing, invoicing, and accounting software system.
  • Represented regional communications company in technology/software failure claim against major manufacturing of communications technology.
  • Counsel to computer hardware seller in case against software manufacturer for cost recovery due to failure of integrated accounting, billing, and inventory management software system.
  • Counsel to fixed wireless broadband network company in pursuing claims for recovery of costs involved in purchase of defective software.
  • Counsel to leading regional developer in pursuing partnership dissolution involving ownership of construction business, building materials company, and over 40 multi-family apartment complexes.
  • Representation of small software/technology company in case against big 4 accounting firm for a failed initial public offering resulting from professional negligence.
  • Represented Internet community development company in suit against former company official for breach of contract, fraud, and embezzlement.
  • Defended Internet company against claims of securities violations and breach of contract for failed joint venture in development of for-profit internet community web site.
  • Assisted national manufacturer of industrial materials for the construction industry in negotiation and purchase of major integrated, multi-site software system for project design, ordering, invoicing, and inventory control

Loren regularly publishes in professional journals, and provides seminars before bar and other professional associations.



Co-Author of “Riddell Williams Environmental Team Helps Secure Washington Supreme Court Victory” (January 2017) (PDF)


Riddell Williams client briefing, July 2016, “Scope of CERCLA ‘Arranger’ Liability Significantly Narrowed.” (PDF)


Bloomberg BNA Daily Environmental Report, March 2016, “PCB Lawsuits Against Monsanto Part of ‘Emerging Trend’.”


Bloomberg BNA Toxics Law Reporter, May 2016, “New Mantra For NW Plaintiffs’ Attorneys: ‘Follow the Moss’. ”


American Gas Association, August 2004 (Panel Chair), “Complex Multiparty Mediation for a Sediment Site.”


U.S. Environmental Protection Agency, March 2004, “Using Alternative Dispute Resolution Systems for Passaic River Clean Up.


Washington State Bar Association, May 2003, “Report on Area-Wide Contamination.”


University of Washington ADR Conference, April 2003, “Cleaning Up A Waterway Using Alternative Dispute Resolution.”


National Business Institute, September 2002, “Conducting Effective Environmental Due Diligence.”


National Business Institute, September 2002, “Key Issues in Wetlands Development.”


Washington State Bar Association, 1995-2002 Board of Editors, Washington Real Property Deskbook, Environmental Volumes.


Washington State Bar Association, 1995-2002, Washington Real Property Deskbook, “Washington’s Clean Air Act.”


Vashon Island CLE Seminar, June 1999, “Ethical Considerations in Environmental Litigation.”


Washington State Bar Association, May 1999, “Environmental Legislation Update.”


11th World Clean Air and Environmental Congress (South Africa), Fall 1998, “Comparison of the Use of Risk Assessment for Human Health and Ecological Assessments in the Developed and Developing Countries.”


Washington State Bar Association, Spring 1997, “Report on Land Use Study Commission.”


National Business Institute, Spring 1996, “Risk Assessment Under the Model Toxics Control Act.”


Vashon Island CLE Seminar, June 1995, “Smelter Site Cleanup.”


University of Washington, Winter 1995, “Federal Clean Air Act Regulations and Their Effect on Land Use.”


Washington State Bar Association, 1991-95, Board of Editors and Regulatory Update Columnist, Environmental and Land Use Law Section Newsletter.


Northwestern School of Law, Spring 1993, “The Model Toxics Control Act’s Implications for Lenders.”


Washington State Bar Association, May 1993, “Washington’s Air Permitting Regulations.”


Executive Enterprises Idaho Seminar, Winter 1993, “The Federal Clean Air Act Operating Permits Program.”


Executive Enterprises Idaho Seminar, Winter 1993, “Hazardous Waste and Underground Storage Tank Regulations.”


Northwestern School of Law, Spring 1992, “Changes to Washington’s Model Toxics Control Act.”


Washington State Bar Association, Winter 1989 (Co-Chair), “Hazardous Substances at a Complex Aquatic Site.”


General Litigation and Technology

Lexis Law Publishing, 1990-2004, Washington Corporate Forms, principal contributor of various corporate, employment, and transactional documentation forms.


Riddell Williams Client Briefing, Spring 2002, “Controlling Runaway Technology Projects.”


Washington CEO Magazine, Technology Roundtable, March 2002 (Moderator), “Making Technology Work.”


Riddell Williams Client Briefing, Fall 2001, “Buying New Technology.”


Riddell Williams Client Briefing, Fall 2001, “Litigating Technology Disputes.”


Mealys Publications, March 2001 (Program Co-Chair), “IT Systems Failure Conference 2001.”


King County Bar Association, November 2000, “Software Licensing Agreements – Form and Enforceability.”


University of Washington, School of Business, Spring 2000, Adjunct Faculty, “Managing Legal Issues.”


King County Bar Association, Spring 2000, “Software Licensing.”


Washington State Bar Association, Fall 1997, “Effective Use of Experts in Litigation.”


Washington State Bar Association, 1992-95, Civil Procedure Desk Book, author of section on discovery matters.

Selected as one of the “75 Top Business Lawyers” in the Seattle Region by Seattle Business Monthly magazine, and as one of “The Best Lawyers in America” by Best Lawyers®.


Chosen as one of the “Best 150 Attorneys” in the Puget Sound Region by Seattle Magazine.


Ranked as one of “America’s Leading Business Lawyers” by Chambers USA.


Designated as a Washington Super Lawyer®.


Achieved the peer reviewed rating of AV Preeminent® by LexisNexis® Martindale-Hubbell®.





Loren has an extensive history of professional and community activities.


Washington Environmental Council, 1989-present

Board member and counsel to State’s leading environmental organization. Served as corporate secretary, vice president for legislative affairs, and chair of legal committee. Acted as WEC’s representative in numerous Department of Ecology negotiated rulemaking projects.


Washington State Regulatory Development Work Groups, 1989-2003

Served, at the request of the Washington Department of Ecology, as key participant in the development of Washington state’s environmental regulatory system. Worked as a member of numerous state-sponsored negotiated rulemaking work groups. These groups have included:

  • Area-Wide Contamination Task Force, 2001-03
  • Model Toxics Control Act Policy Advisory Committee, 1995-97
  • State Environmental Policy Act Advisory Committee, 1994-95
  • Underground Storage Tank Regulations Committee, 1992-93
  • Clean Air Act Operating Permit Regulations Committee, 1992-93
  • Sediment Management Standards Regulations Committee, 1992
  • Model Toxics Control Act Regulatory Work Group, 1989-92


Washington’s Land Use Study Commission, 1995-98

Governor’s appointee to Washington Land Use Study Commission, which was charged with making revisions to the state’s Growth Management Act and with revising and consolidating Washington’s land use and environmental statutes into a unified body of law.


Washington State Boundary Review Board for King County, 1993-97

Governor’s appointee to quasi-judicial body which rules on proposed annexations and incorporation into existing cities of land in unincorporated portions of King County. Resolved disputes among cities regarding annexations.


Washington State Bar Association, 1995-96

Member of the executive board of directors of the Environmental and Land Use Law Section of WSBA.


1000 Friends of Washington, 1992-93

Founding corporate secretary and drafter of corporate bylaws for 1000 Friends of Washington, which is Washington’s leading nonprofit organization devoted to effective growth management and land use planning.

Stanford University Law School, J.D., 1987. Editor of the Stanford Journal of Environmental Law

Oxford University, Nuffield College, postgraduate study, 1984

Harvard University, Kennedy School of Government, M.P.P., 1980

Bowdoin College, A.B., magna cum laude, with high honors in Government, 1978


Environmental Practice Group Celebrates Washington Supreme Court Victory

  The Coalition of Coastal Fisheries held a celebratory “crab feed” in Chinook, Washington this past weekend to thank our Environmental Practice Group for its pro bono representation … read more

Riddell Williams Environmental Team Helps Secure Washington Supreme Court Victory

On January 12, the Riddell Williams Environmental Practice Group obtained a significant victory on behalf of its client, the Coalition of Coastal Fisheries (CCF), at the Washington Supreme … read more

Scope of CERCLA “Arranger” Liability Significantly Narrowed

Airborne discharges of hazardous substances do not give rise to liability under CERCLA, according to a new ruling issued by the Ninth Circuit.  See Pakootas v. Teck Cominco … read more

Chambers USA Recognizes Four Practice Areas and Eight Attorneys from Riddell Williams

The 2016 Chambers and Partners rankings were recently published online for the USA rankings and HNW rankings. Riddell Williams has achieved rankings in both the USA Guide and … read more

Riddell Williams Attorneys Named Super Lawyers, Rising Stars, Top Women Attorneys, and Top 100

Riddell Williams congratulates the following individuals who have been designated 2016 Super Lawyers, Rising Stars, Top Women Attorneys and Top 100 Super Lawyers: 2016 Super Lawyers Bruce J. … read more

PCB Lawsuits Against Monsanto Part of ‘Emerging Trend’

Riddell Williams attorney Loren Dunn is quoted in a recent BNA article, “PCB Lawsuits Against Monsanto Part of ‘Emerging Trend’“. As plaintiffs in six cities move to consolidate … read more

Best Lawyers at Riddell Williams

Of course we think our attorneys at Riddell Williams are the best, now it’s official.  Several Riddell Williams attorneys have been recognized by Best Lawyers for outstanding work. … read more

Washington’s Proposed Water Quality Assessment: New Data, New Techniques May Trigger New Discharge Requirements

Washington State has proposed an updated water quality assessment that identifies state waters that do not meet water quality standards.  Failure to meet the standards can trigger more … read more

Chambers USA Recognizes Four Practice Areas and Six Attorneys from Riddell Williams

The highly regarded Chambers USA recently released its rankings of practice areas and attorneys.  Riddell Williams is pleased to announce that the following practice areas and attorneys were … read more

Municipal Discharger of Stormwater Runoff Liable under CERCLA: Ruling affirms arranger liability for stormwater contamination

June 9, 2010 Newsletter (PDF). Each year billions of gallons of municipal stormwater runoff are discharged to the Nation’s waters. Those discharges often contain significant loadings of key … read more