Threat of explosion “off the table” for California chemical leak in Orange County, officials say

Orange County officials responding to a California chemical leak announced on Monday morning that the threat of a BLEVE, or Boiling Liquid Expanding Vapor Explosion, has been eliminated after an overnight operation.

“We are happy to report that the threat of a BLEVE is now off the table,” Orange County Fire Authority Interim Chief TJ McGovern said. “That threat has been eliminated.”

In a post on X, McGovern and OCFA Incident Commander and Division Chief Craig Covey said crews confirmed a crack on the tank, which led to a pressure release. The tank’s internal temperature has decreased from 100 degrees to 93 degrees.

“That is incredibly positive news as we turn the corner on this incident,” Covey said.

Tens of thousands of Orange County residents in the communities of Garden Grove, Buena Park, Anaheim, Stanton, Westminster and Cypress have been under mandatory evacuation orders since Friday afternoon as officials worked to mitigate the chemical incident emergency at GKN Aerospace. 

Nearly 10 shelters have been opened across the region, many of which have reached or are nearing capacity and straining the resources provided by Red Cross volunteers. Local officlas have worked to facilitate the opening of additional shelters as necessary, with two new sites opening on Sunday, including one at the Orange County Fairgrounds for evacuees in RVs. 

On Sunday, California State Parks officials advised those displaced from their homes that they cannot stay at state parks overnight, including at Bolsa Chica State Park in Huntington Beach. In a post to X, parks officials said that their parking lots and parks were not equipped to accommodate the needs of evacuees. 

California officials are awaiting a response from President Trump regarding Gov. Gavin Newsom’s request on Sunday for a federal emergency declaration. The request was backed by U.S. Sens. Alex Padilla and Adam Schiff of California, and Orange County Rep. Derek Tran. 

On Saturday, Newsom proclaimed a State of Emergency for the Orange County chemical incident, leading to the deployment of nearly 800 first responders and experts to assist local agencies in Garden Grove. Emergency personnel working to respond to the crisis include firefighters, law enforcement, hazmat teams, scientists, toxicologists, engineers, and public health and sheltering experts. 

Orange County Fire Authority Interim Chief TJ McGovern said in a post to X on Sunday evening that crews were preparing for an “all-night mission” to test the pressure of the tank at the center of the chemical leak, which contains methyl methacrylate, a highly flammable substance used in the production of plastics. McGovern said crews hoped to determine if a BLEVE threat, or Boiling Liquid Expanding Vapor Explosion, had been eliminated after a crack was discovered in the tank. 

“The BLEVE threat is the worst-case catastrophic event that we’ve been talking about,” McGovern said. “We are not there yet; we need to run this operation tonight.”

Earlier Sunday, McGovern said that he was hopeful additional tests would lead to the reduction of evacuation zones, but stipulated that such a decision would not be made until officials were absolutely certain that it was safe for the public to return to the area.