Found the following article on msnbc.com from The Associated Press dated 3/4/08.
Dozens flee acid fumes after train derails
Toxic vapors from tanker car blaze close highway in Southern California
MECCA, Calif. - A freight train derailed in the Southern California desert and four tanker cars were leaking hydrochloric and phosphoric acid, forcing home evacuations, authorities said.
No one was injured when nearly 30 of the Union Pacific train’s 65 cars derailed Monday night about 140 miles southeast of Los Angeles. It was headed from West Colton to El Centro.
Initial reports that two tankers were ablaze were incorrect, said James Barnes, director of media information for Union Pacific, adding that only wooden railroad ties were on fire.
About 40 homes remained evacuated Tuesday because of the potentially hazardous fumes, fire officials said.
The four tankers were leaking unknown quantities of hydrochloric acid phosphoric acid, officials said.
Hydrochloric is highly corrosive and can cause burns if it comes into direct contact with skin or eyes. It is used in the production of fertilizers and dyes, and in photographic, textile and rubber industries.
Phosphoric acid is milder and used for rust removal and for the preparation of steel surfaces for painting.
It was not immediately clear why the train derailed, Barnes said.
The acid sent up a 25-foot plume Monday night, Riverside County fire Capt. Julie Hutchinson said.
A smaller cloud, caused by acid reacting with organic material at the scene, still hovered Tuesday morning although it did not represent an immediate public health threat, Hutchinson said.
Barnes said the phosphoric acid was reacting with soil.
“It’s kind of like a smoldering,” Barnes said.
People were being kept out of the area around the derailment site until the acid leaks were stopped and cleanup crews could begin their work.
About 2,000 feet of track suffered damage and 25 trains were delayed, Barnes said, with some rerouted along a route through Salt Lake City.