Martinez Refinery Mishap Spews Black Smoke Into Air

MARTINEZ (CBS 5 / AP / BCN) -- Health officials in Contra Costa County issued a shelter-in-place warning for a couple hours Wednesday for residents in Avon, Clyde and North Concord after Tesoro's Golden Eagle refinery in nearby Martinez spewed black smoke into the sky.

A power outage caused excessive flaring - or the sending of smoke into the air - at the refinery around 4:15 p.m., prompting the warning for people downwind from the plant, Contra Costa County Hazardous Materials Program Director Randy Sawyer said.

Thick, black smoke and flames could be seen coming from five flares at the plant shortly after the incident occurred. Witnesses said they could see the huge flames and billowing smoke several miles away from the refinery.

Paul Andrews, a hazardous materials specialist with the county, described the "flares," which look like smokestacks, as emergency devices at the plant.

While the refinery is located on the outskirts of Martinez near North Concord, because of wind conditions most of the smoke moved toward Clyde and Bay Point.

The smoke contained "unburned hydrocarbons," according to Andrews, with "possible minor amounts of sulfur compounds."

Sawyer said the shelter-in place order issued shortly after the outage had required everyone in the affected areas to remain indoors and close their windows. It was lifted a little after 7 p.m.

"We don't expect it to get any worse," Sawyer said. "That's why we're able to lift the shelter-in-place."

However, a health advisory remained in effect after the shelter warning was lifted because officials said residents who had conditions such as asthma or emphysema were still vulnerable to the smoke.

An all-clear was given about 8:15 p.m.

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