Public can weigh in on Kaiser clean-up

Several documents are ready for public review that will guide the way 512- acre Kaiser Trentwood site is cleaned up. The site lies along the north bank of the Spokane River over the Spokane Valley-Rathdrum Prairie Aquifer. The site has been contaminated during historic aluminum production operations and current uses as an aluminum sheet and plate rolling mill. Kaiser has conducted cleanup operations, but some contaminants still exist there, including volatile organic compounds, polychlorinated biphenyls (PCBs), and metals such as lead, arsenic and chromium. A public meeting will be held at 7 p.m., Thursday, Jan, 26, 2012, at Trent Elementary School, 3303 N. Pines Road, Spokane Valley, to discuss the cleanup alternatives and documents that will guide cleanup at Kaiser. The public has from Jan. 5 through March 6, 2012, to submit comments. The documents describe the extent of soil and groundwater contamination and associated human health and ecological risks at the Kaiser site. They include documents detailing investigations done at the site and the options for cleaning up the remaining contamination. Among the documents is a Human Health and Ecological Risk Assessment, which evaluates risks to human health and the environment from possible exposure to contaminants from the Kaiser site. The assessment confirmed that additional cleanup actions are needed to reduce potential human exposure to the contaminants in soil and groundwater. Results also indicate there are no exposure risks to wildlife in the 25 areas studied within the site. “It’s important that we find out what the public thinks of the options available for cleaning up this site,” said Mike Hibbler, who manages Ecology’s Toxics Cleanup Program in Spokane. “The public’s comments can influence the cleanup options Ecology will select for the site. We don’t have our minds made up already.” The U.S. Government Defense Plant Corp. created the Trentwood facility in 1942 to produce aluminum for World War II aircraft. Kaiser leased the facility in 1946 and later purchased the property. The state’s voter approved Model Toxics Control Act says property owners are liable for cleanup costs. Investigations focused on the southern part of the property where the industrial buildings are located, including the oil house, the cold mill and finishing area, the industrial wastewater treatment area, the re-melt/hot line area, and the truck shop area. In some small areas, petroleum is present on the water table during late summer and fall when the groundwater levels are at their lowest. Kaiser recovered over 4,000 gallons of petroleum product as a result of actions the company took since 1994. The investigation identified three areas of groundwater contamination called plumes. The larger plume contains PCBs and originates in the re-melt area. The other two plumes are being contained with the current cleanup measures. These plumes contain total petroleum hydrocarbons (TPH), which are mostly diesel and heavy oil, along with PCBs. Carcinogenic polycyclic aromatic hydrocarbons (cPAHs) and metals also are found with the petroleum plumes. Currently, actions are being taken to contain the TPH plumes, some of which contain PCBs, and to recover petroleum product. Several contaminants in soil still exceed state standards. Determining which cleanup methods to use at the site is complex because there are multiple contaminants in different locations at various depths in soil as well as in groundwater. Additionally, different technologies have been identified to clean up different contaminants in each of the five main cleanup areas. Next, Ecology will write a Draft Cleanup Action Plan that selects the most appropriate cleanup alternative or alternatives for the site based on current proven scientific technologies, protection of human health and the environment, and public input.