Evacuation orders were rescinded Saturday morning in Riverside County after a chemical reaction in a railroad car parked on private property threatened to cause an explosion, forcing people from their homes two days earlier.
Both directions of the 215 Freeway in Perris were reopened Friday night, although Harley Knox exits remained closed Saturday, officials said.
Authorities continue to urge the public to avoid the area near Harvill and Oleander avenues, where the tanker truck carrying styrene, a highly volatile liquid commonly used in plastic and rubber products, overheated dangerously on Thursday.
Authorities were concerned that if heat and pressure continued to build inside the car, it could explode or create a chemical cloud that could spread over Perris and Moreno Valley, said Captain Richard Cordova of the California Department of Forestry and Fire. Protection in Riverside District.
When styrene is on its way, a stabilizing chemical is added to it to keep it safe, Cordova said. The stabilizer has a life of 45 days. For unknown reasons, the chemical sat in the train car for 55 days, so the stabilizer lost its effectiveness, resulting in the reaction, he said. The car was parked on tracks on private property where the contents of trains are unloaded, he said. He couldn’t say who owns the property or the chemicals, but said the train came from Texas.
Once the authorities were able to get key players involved, including the railcar and chemical manufacturers, they learned that it was possible to connect a fire hose to the train, which has built-in coils that allow water to flow through the train. tank, Cordova, lead. said. After setting up the system Friday night, they were able to lower the temperature in the car from 350 degrees to 230 degrees, he said. Styrene usually stays at about 85 degrees.
Crews had been monitoring the temperature using a drone, but as things cooled down, they were able to physically access the area and get more accurate readings using a thermal energy camera, Cordova said. They were also able to add more stabilizer to the styrene, he said.
The crew continued to work Saturday to get the car as cool as possible, after which a private hazmat team would unload the contents, Cordova said. No long-term effects from the leak are expected, he said.
Firefighters and personnel with hazardous materials first responded to large plumes of smoke coming from the train carriage around 7:40 p.m. on Thursday. Authorities ordered the evacuation of 170 homes and several businesses.
By Saturday, the danger had diminished to the point where people could return home, provided they steered clear of the area where the teams were still working, Cordova said.
Times staff writers Alexandra E. Petri and Gregory Yee contributed to this report.