(CBS) RICHMOND - East Bay residents used a town hall meeting Tuesday to sound off at Chevron executives over a massive fire at a refinery in Richmond Monday. Hundreds of residents sought medical treatment for respiratory problems, but experts concluded Tuesday it was "not a significant health concern."
A two-hour meeting was held to address those concerns a day after the 3-alarm fire broke out at the refinery, burning through the night, reports CBS San Francisco.
Several hundred residents packed Richmond's Civic Center Auditorium for the meeting to demand answers from company and local officials about the fire that sent thick smoke, soot and other toxins into the air and prompted the county to issue a shelter-in-place warning, urging Richmond, North Richmond and San Pablo residents to stay inside their homes.
Nigel Hearne, the refinery's manager, apologized to community.
"Hopefully this is seen as a first right step to doing the right thing in the community," Hearne said. "Our goal is to be incident-free, and frankly, last night, we did not meet that expectation."
Hearne said Chevron's top priorities now are determining the root cause of the fire and ensuring safe access to the site for the refinery's workers as well as preventing future incidents.
"If we can get to the root cause of the incident, we can prevent it from happening again," he said.
Many of the meeting's attendees expressed fear over the fire's impact on their short-term and long-term health and safety as well as anger at Chevron and the county's handling of the incident.
Several dozen carried signs with messages such as "People's Health, Not Corporate Wealth" or "Chevron out of Richmond." Some wore gas masks.
Several speakers who addressed Hearne and the rest of the panel Tuesday said they suffered irritation, sore throats, shortness of breath and headaches.
"I saw a plume of smoke about 60 feet high ... with dirty air for me to breathe," said North Richmond resident the Rev. Kenneth Davis, of North Richmond Missionary Baptist Church. "How long can I hold my breath? What about our dogs, our cats, our horses--what about our children?"
But inspectors with the Bay Area Air Quality Management District said test results received from a lab on Tuesday showed pollution levels during the incident were well below the federal health standards.
Meanwhile, Chevron officials on Tuesday said the fire at the refinery's No. 4 crude unit was caused by a minor hydrocarbon leak that later grew larger.
Chevron's head of emergency services, Mark Ayers, said the leak was first detected at about 4:30 p.m. Monday, but county health officials weren't notified because there were "no thoughts it would impact the community."
As workers tried to stop leak, it grew larger - eventually forcing them to leave the area due to the safety risk, Ayers said. As the leak expanded, it created a "big vapor release and ignition." What actually caused the leak remained under investigation on Tuesday.
Residents in the area claimed to hear explosions around the time the fire started, but Chevron has maintained there was no explosion.
Contra Costa Health Services officials said about 18,800 calls went out over the agency's automated emergency phone alert system to residents after they received notice of the blaze at 6:40 p.m., although some residents in the path of the smoke expressed concern that they received no notification.
The 3-alarm fire, battled by roughly 80 firefighters, was contained just before 11 p.m. and the shelter-in-place order was lifted shortly thereafter.
Throughout the day on Tuesday, officials said more fluid from the leak was safely being burned off to ensure there was no threat of another ignition. That small fire was described by authorities as being about the size of a basketball.
With the damage assessment and repairs to the refinery's crude unit expected to take some time to complete, it remained completely shut down. The company declined to comment about the impact on the region's gas prices, which spiked on Tuesday due to an anticipated production shortage.
Despite the mayor's concerns, investigators with California's Division of Occupational Safety and Health have described Chevron's emergency response as "excellent."
A similar fire occurred at the refinery in 2007, but the company noted that it was located in a different processing unit than the one where the fire erupted on Monday