Emergency crews are working to stabilize a 34,000-gallon tank of methyl methacrylate at a GKN Aerospace facility after internal temperatures reached critical levels.Governor Gavin Newsom declared a state of emergency for Orange County as the risk of a thermal runaway reaction prompted the evacuation of 40,000 local residents.Firefighters continue to cool the tank externally while specialists attempt to resolve a clogged valve that currently prevents the injection of neutralizing agents.