Fed board issues written report on deadly Sierra Chemical blast

Sandra Chereb

Saturday, Sept. 26, 1998 | 10:13 a.m.

RENO, Nev. - Better training and safety procedures could have prevented a deadly blast at an explosives plant east of Reno, a federal safety board said.

A 102-page report issued Friday by the U.S. Chemical Safety and Hazard Investigation Board concluded that poor worker training, safety programs, operating procedures and regulatory oversight led to the Jan. 7 blast at the Sierra Chemical Co. plant in Mustang that killed four workers and injured six.

"Workers at the plant had little formal training in safely handling material used to manufacture explosives," the board said.

But Sierra Chemical attorney Bruce Laxalt condemned the report, calling it an affront to immigrant workers.

Most of the workers were Hispanic and spoke little if any English. The report cited Sierra Chemical's failure to provide training and procedure manuals in their native language as contributing factors.

Laxalt denounced the finding.

"This report is an insult to Hispanic workers everywhere," he said at a news conference shortly after the report was issued. "We highly dispute the board's conclusion that just because they don't speak English they are unskilled and untrained."

Laxalt said the 11-person crew was a "highly-skilled production team" and received regular safety and procedural training in their native language.

The safety board concluded that the initial blast occurred in Booster Room 2, where volatile brews of substances, including TNT and PETN, were mixed to make explosives used in the mining industry.

Seismic data from the University of Nevada, Reno also determined the location of the initial blast, the board said.

Sierra Chemical has said its own experts determined from blast patterns that the initial explosion occurred in the PETN storage room.

While it was difficult to pinpoint the exact cause of the first explosion, the report said evidence suggests it was most likely triggered when a worker who left early the day before left 50-100 pounds of base mixture in a large mixing pot.

Investigators believe the mixture stratified and hardened overnight. The next morning, when the same worker turned the mixer's motor on, the mixing blade that was embedded in the mixture likely detonated the explosives through impact, shearing or friction, the report said.

The shock wave detonated thousands of pounds of explosives, destroying that room, the report said, adding that burning or flying debris then triggered a second explosion 3.5 seconds later at building not far away where PETN was stored.

That finding contradicted Sierra Chemical's argument that the initial explosion occurred in the storage room and might have been the work of saboteurs.

"All the safety board has come up with is possible scenarios," Laxalt said, adding that the exact cause may never be known.

But Laxalt said the explosions could not have happened as the board described.

He said the last worker to leave the night before said the mixture left in the mixing pot was 1-1 1/2 inches below the mixing blade.

Laxalt added that mixing pots were routinely left on overnight to prevent materials from solidifying, and that each was equipped "so even if that happened, a trip-switch would have activated."

Friday's report was the first written finding by the board that began operations two days before the Sierra Chemical explosion.

Laxalt said the board's investigators were inexperienced and their investigation flawed.

"The board ... has refused all industry expert input, despite the acknowledged inexperience of their own investigators," Laxalt said. "We look forward to going to court on this matter on an even playing field, with cross examination, where the truth will come out."

Board spokesman Bill Riley refuted Laxalt's claims that board investigators are inexperienced and that industry experts were left out.

"The idea that we're dealing with a bunch of inexperienced people is just not true," he said from his Washington D.C. office.

"If anything, although we're a new board, our investigators are very experienced and our report was developed not only by those very experienced investigators, but reviewed by a whole host of experts, including from NASA, the Department of Defense, the U.S. Postal Service and some of the national laboratories," Riley said.

He added that the Institute of Manufacturers off Explosives helped develop recommendations contained in the report and met with the board on numerous occasions.

"We have not by any means closed industry out from trying to contribute to this report," Riley said.

The report also recommended more frequent inspections by state regulators, something Gov. Bob Miller has already ordered. It also called on the explosives industry to develop standard training guidelines.

Nevada regulators levied $1 million in fines against the company following the explosion. The company is appealing through an administrative process.

Two lawsuits filed against Sierra Chemical by victims' families and others have been consolidated into one case, Laxalt said.