HEALDSBURG (CBS SF) – The mystery of who left two 55-gallon drums containing a toxic and deadly acid on the side of the two roads in northern Sonoma County remains unsolved, Healdsburg’s fire marshal said Thursday.

The first drum was found June 4 on Kinley Drive on the edge of a vineyard property in Healdsburg and the second was found June 6 on the side of Old Redwood Highway in unincorporated Sonoma County in the Sonoma County Fire Protection District based in Windsor, Fire Marshal Linda Collister said.

The label on the first drum indicated it contained fluorozirconic acid used to clean metal, glass etching and for optical glass production, Collister said.

Test strips dipped in the first drum indicated the contents had a zero pH value, the strongest of acids, Collister said. The second drum had no label but it also contained a strong acid.

A hazardous materials team with Permit Sonoma responded and the state Department of Toxic Substances Control removed the drums.

The drums weighed hundreds of pounds, and whoever left them there probably used a vehicle with a lift gate to unload them and place them upright, Collister said.

It’s possible the owner of the drums hired a company to dispose of them and that second party abandoned then, Collister said.

“The original owner is still responsible for their proper disposal,” she said.

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