Holcim Inc

Former cement manufacturing left two deposits of cement kiln dust (CKD) at the Holcim Inc site. Investigations showed the CKD had contaminated soil and groundwater.

The cleanup remedy was constructed from July through November 2016. A CKD deposit near the Spokane River was excavated and combined with the other CKD deposit further away from the river. The CKD was then covered with an engineered cap to keep people, wildlife, and precipitation from contacting the contamination.

The Holcim Inc site is 24 acres. The largest part of the site is owned by Holcim (US), Inc. The remaining parts, which are now clean, are owned by the City of Spokane Valley and the Neighborhood, Inc. Coyote Rock Development.  

The site was used for manufacturing cement from 1910 to 1967. During that time, CKD was deposited on the site. Soil sample results confirmed one CKD deposit about 109,100 cubic yards in volume on the Holcim property. Another CKD deposit in soil, about 12,300 cubic yards in volume, was on the city property.

The CKD contains various contaminants that exceed state standards, including arsenic, cadmium, and lead. In addition, some CKD deposits were very alkaline with a pH greater than 12.5, which is corrosive and considered dangerous waste if disturbed. 

Other areas of the site had soil contaminated with benzene, carcinogenic polycyclic aromatic hydrocarbons, and gasoline. 

In 2011, Ecology entered into an Agreed Order with Holcim (US), Inc., and the City of Spokane Valley. The order required these two property owners to conduct a Remedial Investigation and Feasibility Study at the Holcim Inc site to define the extent and location of contamination and evaluate cleanup options.

On February 13, 2014, during the public comment period for the draft Remedial Investigation and Feasibility Study, Ecology hosted a public meeting to provide an overview of the Holcim Inc site and results of the reports. We discussed soil and groundwater results, the cleanup options, and answered questions. Ecology published a response to comments following the comment period.

Ecology selected a modified alternative 4 in the Cleanup Action Plan, held a public comment period on the draft plan in late 2015, and received one comment. We published our response to comments and finalized the plan without revision.