Investigation and Remediation of Pesticide Contaminated Soils

In 2008, during development of a parcel and construction of a retail building for lease, stained and discolored soils were encountered in the building footprint and stormwater detention pond excavations. The civil engineer recommended that investigation and remediation be completed by an environmental consultant and recommended that the developer consider using Fulcrum.

Fulcrum’s initial site assessment was completed on the same day as the initial phone inquiry of our office. Initial impression of the site was consistent with two primary concerns, the presence of a large area of buried white granular material, later shown to be primary spent lime and excavated due to structural instability concerns, and an area of yellow, green, and orange discolored soils. Fulcrum was directed to proceed with soil sample collection during our initial site assessment. Laboratory results, received on a rush turn-around-time, confirmed the presence of DDT, dieldrin, aldrin, and others in the area of discolored soils.

To minimize the disruption to continued site development, Fulcrum completed a series of test pits across the site to develop a general understanding of the extent of contaminated soils. With an understanding of the extent of contamination, Fulcrum directed the excavation and stockpiling of discolored soils. Waste characterization, and the understanding that the contaminated soil could not reasonably have resulted from an onsite spill, but rather as a result of imported soils, enabled the contaminated soil to be regulated as a non-hazardous waste. At one point nearly 25% of the parcel was covered by stockpiled soils. However, the stockpiled soils were strategically placed near an access road allowed for easy loading and transport of the contaminated soils to the Roosevelt Regional Landfill in Roosevelt, Washington.    

Laboratory analysis also demonstrated that the area of spent lime did not require remediation. However, the civil engineer to be insufficient to support the building weight. Following a complete waste characterization, the spent lime was shown to be an inert solid waste, and was excavated from the site for offsite disposal.  

At the conclusion of site investigation, more than 50 soil samples for laboratory analysis and excavation of approximately 25% of the site was required. More than 1,100 tons of contaminated soil was excavated and disposed. Although delays in the construction schedule did occur, the developers decisive decisions and Fulcrum’s effective communications with local Ecology staff allowed for the prompt removal of contaminated soils from the site. Following a review under the Voluntary Cleanup Program, the site received a No Further Action determination.    

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207 West Boone Avenue
Spokane, WA 99201
p: 509.459.9220

406 North 2nd Street
Yakima, WA 98901
p: 509.574.0839