Chemical Cloud Forces Key Street Closures

A thick, pale yellow cloud of a nontoxic chemical from Mobil Oil’s Torrance refinery wafted over the eastern part of that city Tuesday afternoon, forcing fire officials to close off two major thoroughfares at the peak of rush hour, but causing no injuries.

Mobil officials said the material, called silica alumina, was released shortly after 5 p.m. during an accidental reversal of operations in the refinery. Fire officials, who initially believed the cloud was composed of sulfur dioxide, advised people to remain inside as the cloud passed over, but they did not order any evacuations, Torrance Fire Department spokesman Jim Swing said.

Air Quality Management District inspectors were en route from Long Beach Tuesday evening to investigate the cause of the accident and determine how much of the gas had been released, spokesman Bill Kelley said.