At least 170 residents were ordered to leave the area near Harvill and Oleander avenues in Perris, where a rail car that was parked on the tracks and carrying a chemical substance overheated, leading to a hazardous spill on August 11. Two days later on August 13, the evac order was lifted.
While no big explosion occurred, authorities from the Riverside County Fire Department, one of the agencies leading the response effort, ended up issuing a second evacuation order to an expanded area the day after the spill.
The train car was “red hot” and too dangerous for officials to approach, said John Crater, Cal Fire Riverside County division chief.
By the afternoon on August 12, crews were using drones with infrared technology to monitor the tank’s temperature to ensure it did not reach hazardous levels, said Cal Fire Riverside County Battalion Chief Mark Scoville.
“Currently what we have going on is a very dynamic situation,” Scoville said at the time. “The tank car in question off-gassed last night. We have not had any further off-gasses from it.”
Oscar Torres, a fire captain working on the incident, said the temperature readings were “trending in a positive direction” but had not dropped enough to allow further action.
The Riverside County Fire Department responded to reports of large plumes of smoke coming from a rail car parked on the tracks in Perris around 7:40 p.m. August 11, Crater said. A HazMat team was sent to the scene.
Officials discovered a rail car had dangerously overheated and spilled styrene, a highly volatile liquid typically used in plastic and rubber products. The train was stopped at the time of the reported incident.
Residents and businesses within about a half-mile of the affected area were ordered to evacuate, and parts of the 215 were shut down.
Styrene typically stays at 85 degrees; the chemical in the rail car had reached at least 323 degrees. If things had gotten worse with the spill, the situation could have had serious implications on the area’s infrastructure, Crater said.
Officials throughout the day monitored outside temperatures, which could have affected the chemical activity within the rail car.
The South Coast Air Quality Management District was on the scene to assist with the investigation and conduct air monitoring efforts.
Crater spoke with experts across the country who said it could take up to three days for the situation to cool down.
“It could get worse before it gets better,” he said at the time, adding if heat and pressure built up in the car, it could lead to some “sort of violent explosion.”