"As a result there was some black smoke that came off," Duazo said. "It appears that some odors came off, so we have some air monitors downwind from the refinery."
The Department of Health Services says the smoke, which was rapidly dispersed by brisk northerly winds, should not pose a hazard to most people in the area.
Just after 2 p.m., Tesoro issued a statement on the incident:
At approximately 11:47 PST this morning, Tesoro Martinez experienced a loss of our primary steam generation unit that caused upsets in several process units. These upsets resulted in flaring with visible smoke. A Community Warning System Level 2 was activated per procedure, due to the smoke drifting offsite.
There were no injuries as a result of this event. We do not expect any adverse health effects. We are working closely with Contra Costa County health personnel and other regulatory agencies.
At this time, the steam generation unit is back on-line, and the refinery is currently in stable condition at reduced rates. The refinery is no longer flaring.
Our main priority is to safely return the refinery to normal operations and to minimize the impact to the community and the environment.
As of 1400, the event has been downgraded to a CWS Level 0. Additional information will be provided as it becomes available.