On the heels of massive Chevron refinery fire on Monday, another small fire broke out at the Richmond plant on Wednesday, and hours earlier, a false alarm was sounded off at the Shell refinery in Martinez.
Chevron's Justin Higgs said about 11:30 a.m. Wednesday, there was a small fire related to Monday evening's refinery fire, which burned for hours, caused three injuries, and at least 600 people to be seen at hospitals for respiratory problems. The fire was put out in minutes, Higgs said, adding that he didn't know why it started.
About 7 a.m., a Contra Costa County level 3 shelter-in-place that was ordered, which turned out to be an accident sent from the Shell refinery in Martinez.
Shell spokeswoman Erin Hallisy said the plant was conducting a "level zero" operation, which had nothing to do with Chevron. During what is normally a low-risk procedure, Hallisy said there was a miscommunication, and somehow the level 3 alert was issued.
For all the alarms, real or not, it turns out, the county's state-of-the art warning system that was activated in the wake of Monday's fire at the Chevron refinery in Richmond worked as planned - for the most part.
However, records also show some residents waited up to three hours to receive an emergency telephone call that advised them to stay indoors.
The estimated 20,000 telephone calls sent out Monday may have jammed lines and caused delays to residents living in the smoke plume’s immediate path.
Katherine Hern, manager of the Contra Costa County Community Warning System, noted that the first wave of calls went to the 2,600 residents living closest to the fire at 6:40 p.m., two minutes after Chevron officials reported a "Level 3" incident at the refinery.
The Level 3 classification is the most serious. It calls for residents to go inside, close windows, turn off air conditioners and seal off doors with damp towels.
Six minutes later, a second round of automated calls went to more than 17,000 residents living downwind from the black plume that drifted east.
Hern said some of those residents did not receive the recorded warning until at least 9:30 p.m., possibly because the computer could only meter out 500 to 1,000 calls at a time.
Calls that went unanswered bounced back to the control center to be redialed and contributed to the backlog.
To see an earlier video on the investigation into the fire, click here.
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Lisa Fernandez and Christie Smith contributed to this report.