DuPont Works Site Remediation/Redevelopment

Dupont, Washington
Project Overview

The former DuPont Works Site in DuPont, Washington was used by the DuPont Chemical Company to manufacture explosives for over 70 years.  Explosive manufacturing, support, and storage activities resulted in contaminated soil throughout the 841-acre property, which was one of the largest MTCA sites in the state.  The site contained over 200 buildings, magazines for storing explosives, oil pipelines, narrow-gauge and standard-gauge railroad tracks, waste landfills, and numerous areas impacted by explosives, metals, and petroleum compounds.

PIONEER, in conjunction with Pacific Environmental and Redevelopment Corporation (which is one of several companies with which PIONEER has a unilateral contract agreement), served as the day-to-day project managers for all aspects of the hazardous waste site cleanup project.  We successfully completed or directed the MTCA remedial investigation, risk assessment, feasibility study, cleanup action plan, cultural resources protection plan, public participation and community outreach programs, remedial design, remedial action, and no further action documentation.  

Our Solution

The selected site remedy included the following remedial-action components:

  • Highly-contaminated soil was disposed of off site
  • Soil with high constituent concentrations and the “right” soil properties was washed 
  • Over one million cubic yards of soil were excavated and placed in designated areas (referred to as placement areas)
  • An 18-hole golf course was constructed over placement areas as an engineered cap
  • The remaining portions of the property were prepared for redevelopment

The selected remedy ultimately resulted in 92 percent of the impacted soil either being cleaned and recycled, or used as construction materials capped on-site.  The remaining eight percent of impacted soil was disposed of at an approved landfill.  Once remediation was complete, the 18-hole championship golf course was sold to the Pacific Northwest Golf Association, 330 acres of commercial property were sold to a large commercial real estate company, and 400 acres of industrial property were sold to a gravel producer. 


The transformation of this brownfield to a greenfield was a remarkable achievement due to the size of the project, changing MTCA regulations, significant cultural and historical resources present at the site (including over 40 Native American graves, an ancient Native American shell midden site, and the original Hudson Bay Fort in Puget Sound), and the variety of stakeholders that were actively involved in the project.  

Once completed, the remediated property was put up for sale resulting in selling:

  • an 18-hole championship golf course to the Pacific Northwest Golf Association;
  • 330 acres of commercial property to a large commercial real estate REIT; and
  • 400 acres of industrial property to a gravel producer.


Other Projects

PIONEER has managed numerous environmental projects throughout the United States and abroad.  We have conducted investigations at large, complex sites as well as small, simple sites.  Our project managers provide the same high level of customer service and attention to detail regardless of the size of the project.  The projects highlighted on our website are generally representative of our work.  For additional project examples, please contact us.

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