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Cleanup of nonhazardous biosolids spill in Kittitas County completed within 24 hours

Summary

Cleanup of a nonhazardous biosolids spill near Blewett Pass was completed within 24 hours thanks to a prompt, coordinated response by King County’s Wastewater Treatment Division, the Washington State Department of Ecology and Kittitas County Public Health.

Story

Cleanup of a nonhazardous biosolids spill near Blewett Pass was completed within 24 hours thanks to a prompt, coordinated response by King County’s Wastewater Treatment Division, the Washington State Department of Ecology and Kittitas County Public Health.

The spill occurred at about 5:15 a.m. Monday when a semi-truck operated by a King County contractor, Skagit Transportation, hit an icy patch on Highway 97. The trailer overturned at Milepost 157 near Mineral Springs, spilling about 15 tons of nonhazardous Class B biosolids in Swauk Creek.

Crews used two vactor trucks to vacuum up spilled material and completed cleanup about 3:30 a.m. on Tuesday. 

King County’s Class B biosolids are a treated, nutrient-rich by-product of the wastewater treatment process used to enrich soils and stimulate plant growth. Biosolids naturally return carbon and nutrients to soils, and reduce wind erosion. The treatment and usage of biosolids is strictly regulated by the state, and the product is consistently monitored for safety and quality. Biosolids are nontoxic.

Because a very small percentage of pathogens may still be present in treated biosolids, the public is advised to keep themselves and any pets away from the area until the Kittitas County Public Health Department is able to rule out any potential health risks.

Over the next week, employees with King County’s environmental lab will continue coordinating with health and regulatory agencies to monitor water quality in Swauk Creek.

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