What happened

A large fire erupted while workers processed tetrazole powder at Stericycle-Tacoma, operating as Burlington Environmental on the Tacoma Tideflats. The facility had accepted 510 drums of the reactive airbag-inflator chemical and was required to send them to a licensed incinerator. Instead, workers emptied several dozen drums in preparation for loading the waste into a railcar for landfill disposal. The material ignited during handling and damaged the processing building, but employees escaped without injury. Washington Department of Ecology investigators later found improper waste and fire-residue management, misleading or incomplete documentation, inadequate training and failures to follow facility procedures. A follow-up inspection found further compliance deficiencies, and a separate smaller shredder fire occurred on 22 November after residual liquid chemicals were allowed to mix. Ecology issued a $1.956 million penalty in October 2019 and gave the operator 30 days to comply or risk permit revocation. Stericycle subsequently agreed to pay $2.2 million to settle combined penalties issued in 2019; the settlement also imposed training, testing and operating commitments on the facility's new owner, Clean Earth.

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