Hayward company dumps chemicals in Alameda County creek

A Hayward painting company admitted Thursday that at least one of its workers dumped sealcoating liquid into a creek in an unincorporated area of Alameda County, angering residents who demanded the county clean the water.

Black Diamond Paving & Concrete spilled “a very small amount of sealcoat” into Sulphur Creek just east of Hayward, said Dawn Launer, a spokeswoman for the company.

Less than three gallons of the substance — a liquid mixture applied to asphalt for preservation — washed into the creek from brooms used to apply it, Launer said.

A neighbor spotted a worker opening a fire hydrant to wash off equipment Wednesday afternoon, he said.

Higgins said he called authorities but it took hours to get a response, saying unincorporated regions of Alameda County are often overlooked.