880-Acre Manufacturing Area Contaminated with Heavy Metals & Residual Explosives

Safe, Effective Cleanup Beats Deadline & Saves $1.2 Million for Land Developer

Once part of an explosives manufacturing facility dating back to the early 1900s, the land had gone unused since the plant closed. Many decades later, Weyerhaeuser purchased the site as part of a 3,300-acre tract intended for a mixed-use real estate project. Before work on the real estate development could begin, the site required remediation to remove heavy metal and residual explosives that remained in the areas where numerous plant facilities had been located.

Spurred by an impending change in the Environmental Protection Agency’s land disposal restriction (LOR) for handling hazardous wastes, Weyerhaeuser and the Pacific Environmental Remediation Corporation (PERC), and Jeff King, owner of PERC and co-founder of I2M Associates, LLC, promptly developed a remediation plan that focused first efforts on areas of significant heavy-metal contamination. Site work was scheduled so that hazardous waste would be treated or disposed of within 60 days, the time remaining before the new LOR restrictions were to take effect. Had the project not been completed before the new LOR restrictions went into effect, 4,000 tons of contaminated material would have required stabilization prior to disposal at an estimated cost of $1.2 million. In addition to processing this volume of waste, remediation crews deliberately initiated more than 50 detonations to clear out residual explosives remaining in the old nitroglycerin manufacturing and transferring areas over much of the property designed to optimize safety controls of the day. These blasts averaged 30 to 40 pounds of dynamite each, with some detonations requiring up to 200 pounds. Sympathetic detonations of residual materials left craters in the area the size of large trucks.

The next phase of the project required the excavation of more than 80,000 cubic yards of material, which had to be screened, stockpiled, and covered or disposed offsite. More than 1,500 55-gallon drums without lids, and partly filled with a mixture of rain water and chemicals, were disposed offsite.

Remediation of the former DuPont plant site was completed and the large property incorporated into the Northwest landing project developed by Weyerhaeuser, which included a world class golf course, the construction of which was managed by Jeff King (PERC).