It was a tense scene Wednesday in Torrance, California, as ExxonMobil officials responded to allegations that last February's refinery explosion could have resulted in a poisonous — and potentially deadly — chemical cloud, traveling for miles through neighborhoods near the facility.
"It's absolutely unacceptable that the residents of Torrance were blanketed with ash last year," Michelle Kinman, a Torrance resident, said.
ExxonMobil official Kenneth Dilley also said he believed safety systems protected the workers.
"Nothing is more important to ExxonMobil than the safety of our employees, of our contractors and of our neighbors," said Brian Ablett, of ExxonMobil.
The comment was met by applause at the overflowing auditorium, but the U.S. Chemical Safety Board and Congressman Ted Lieu said Exxon was not fully cooperating with the federal agency's investigation.
"We want to know what ExxonMobil is hiding. About half the document requests that the Chemical Safety Board has issued, these subpoenas, Exxon Mobil has refused to respond to," Congressman Ted Lieu.
A series of systematic breakdowns began six days before the Feb. 18, 2015 explosion, according to the U.S. Chemical Safety Board.
The Board said an "expander" forced the plant's "fluid catalytic cracking" unit to be shut down. The shutdown forced steam into a reactor.
When a worker reduced the flow of steams, it caused hydrocarbons to flow into another piece of equipment in the plant, which then caused the explosion.
The Chemical Board was alleging that because Exxon deviated from standard procedures, which contributed to the explosion.
ExxonMobil has handed over about 80 percent of the documents that have been requested.
"We've provided everything that we think will help them lead to the potential cause of the February 18th incident," Ablett of Exxon Mobil said.
When asked why Exxon has not handed over 100 percent of the documents, Abeltt said:
"Again, we mentioned earlier, there are questions about jurisdiction and agency overreach."
State regulators issued 19 citations against ExxonMobil and proposed penalties totaling $566,600 in response to the explosion.
City News Service contributed to this article.