The McCormick & Baxter site is a former wood treatment facility located on the banks of the Willamette River in Portland, Oregon. Chemicals used on the site had penetrated into soils and were making their way to the Willamette River. This site was listed as a Superfund Clean-up Site by the U.S. Environmental Protection Agency in June of 1994.
Clean-up activities at this site were divided into three areas: upland soils, groundwater, and river sediments. Armortec® hard armor was used in the third and final phase of site rehabilitation and provided approximately 300,000 sf of ArmorFlex articulating concrete block mats for erosion control on the river bank. In this phase of clean-up, existing non-aqueous phase liquid seeps were covered with organophyllic clays, a material designed to absorb these compounds, and then a silt cap was placed over the entire upland soil interface.
ArmorFlex Class 40L and 70L mats were used in conjunction with a woven geotextile fabric and a layer of crushed stone to armor the silt cap and protect it from wave action. Even though this site is located on the banks of the Willamette River, the design criterion was centered on stern waves from large ships heading up the river to the Port of Portland. After installation of the ArmorFlex mattress system, upland areas were re-graded with clean fill materials and topsoil to facilitate vegetative growth.
This previously industrial site on the banks of the Willamette River is now in the final stages of completion resulting in a clean, safe site that is ready for re-use. Previous impacts to water quality, wildlife, fisheries and the Willamette River basin have been mitigated through the cooperation of the U.S. Environmental Protection Agency, Oregon Department of Environmental Quality, Ecology and Environmental Inc. and Remtech.