More than 40,000 residents of Orange County, California, are under evacuation orders due to the risk of an explosion from a tank containing a toxic chemical.
Authorities have spent the last two days trying to prevent the tank, which contained MMA (methyl methacrylate), from exploding after it overheated. They issued the orders for a 23 square kilometer area around the facility.
MMA is used in the manufacture of plastics and can cause respiratory problems in humans, according to the EPA (Environmental Protection Agency).
The tank’s temperature is currently stabilized, which “gives us time to continue to analyze the situation,” Orange County Fire Division Chief and Unified Incident Commander Craig Covey said in a late afternoon update Friday. He added that there is a team working, both locally and across the country, to prevent the tank from exploding or leaking.
On Friday, police issued an emergency alert to warn people and posted information about the orders on social media, Garden Grove Police Chief Amir El-Farra said.
About 15% of people (about six thousand residents) in the area refused to leave, he said. Thirteen schools and two Garden Grove Unified School District facilities were also evacuated Friday morning.
The industrial site where the tank is situated is about five miles from and about six miles from Knott’s Berry Theme Park.
MMA is heavier than air, Covey said at Friday’s news conference, and air should be safe outside the region, Dr. Regina Chinsio-Kwong, Orange County health director, said in a later update.
“This is going to happen unless some genius behind me figures out how we can mitigate this incident,” Covey said, emphasizing the need for mobilization.
Exposure to MMA can cause serious respiratory problems, including “significant irritation” to the lungs and nasal passages, as well as dizziness and nausea, Chinsio-Kwong said.
There aren’t many documented cases of human interaction, so it’s unpredictable what the effects of a possible explosion would be on the population, she said, encouraging people to stay out of the region for that reason.
“We are living in unprecedented times and have limited information,” Chinsio-Kwong said.
The chemical, which is currently not detected in the air, can produce a fruity odor, although smelling it does not mean exposure was enough to cause symptoms, she said in another update.
Authorities initially responded to a vapor leak from the tank containing MMA at the Garden Grove facility on Thursday, Orange County Fire Department Interim Chief TJ McGovern said Friday.
One of three tanks at the site experienced a rise in temperature and triggered a relief valve and sprinklers to try to cool the tank, he said. The other two tanks were neutralized with a chemical agent or do not pose a risk.
Evacuation orders were issued for the area on Thursday, but were lifted that same night after steam conditions improved, McGovern said.
As crews attempted to remove and contain the product from one of the tanks, they noticed that the valve was damaged, preventing the chemical from being removed. This prompted local authorities to reinstate the , he explained.
“I was sleeping at home until this morning when they told us we had to leave,” resident Diane Chavira told the affiliate CNNKCAL, forcing her to pick up her four dogs and leave the area.
McGovern emphasized that there was no vapor coming from the tank on Friday and that officials continue to monitor air quality.
The manufacturer’s response team tried everything but was unable to mitigate the crisis, Covey said Friday. The only two options given to authorities were that the tank would rupture and leak the 26,500 liters of MMA into the surrounding parking lot, or that the container would explode, he said.
A CNN contacted GKN Aerospace Transparency, owner of the facility, for information about their efforts to manage the emergency.
“This product is highly volatile, highly toxic and highly flammable,” Covey said.
Authorities warned that there were many factors that could contribute to the tank’s rupture, which is why they expanded the orders to cover such a large area.
“People need to get out of their homes and get to a safe place because when that happens, depending on the wind direction, we can’t control the weather,” Covey said.
