The FBI has executed a search warrant at the Southern California facility where an overheated chemical tank prompted the evacuation of roughly 50,000 residents last month amid fears of an explosion.
The warrant, signed by a federal judge last week, authorizes investigators to seize documents and records related to the storage, use, and disposal of methyl methacrylate, the highly flammable chemical contained in the damaged tank.
Investigators are also seeking samples from any tank, tote, drum, vessel, or other container believed to contain or previously have contained methyl methacrylate or other hazardous substances. The warrant further authorizes the seizure of records related to cooling systems and other equipment used to regulate the chemical’s temperature.
The search warrant marks an escalation in the investigation into the May 21 incident at the Orange County-based GKN facility, where an estimated 6,000 to 7,000 gallons of methyl methacrylate became unstable. The chemical is commonly used in the production of plastics and coatings, including Plexiglas and dental prosthetics.
Authorities ordered the evacuation of approximately 50,000 residents in Garden Grove and Stanton after concerns that the tank could either explode or release its toxic contents. Officials released a public blast-radius map showing the areas that could be affected by an explosion and toxic plume. The emergency stemmed from a malfunction involving a valve used to relieve pressure inside the tank. The crisis ended when a crack formed in the damaged vessel, allowing pressure to dissipate and enabling authorities to lift evacuation orders and allow residents to return home.
