Hazards at Nevada Plant Blamed for Explosion

An explosion that killed two people, injured 350 others and caused $73 million in damage at a southern Nevada rocket fuel plant last May resulted from hazardous working conditions that allowed a small fire to become a runaway blaze, according to a United Steelworkers Union report released Thursday.

The union report analyzing the May 4 explosion at the Pacific Engineering and Production Co. (PEPCON) plant in Henderson, Nev., places primary blame for the disaster on the company because it failed to install adequate fire-suppression systems, repair faulty electrical equipment, heed warnings from workers and observe basic safety codes.

The report, compiled by the union’s safety and health staff, also criticized the Nevada Division of Occupational Safety and Health (NDOSH) and the Clark County Fire Department for failing to bring the plant into compliance or conduct routine inspections that could have prevented the disaster.

Company officials disputed the claims in the union’s 53-page report and said a natural gas leak prompted the tragedy, which wiped out half of the nation’s production capacity for ammonium perchlorate, a key ingredient in solid-fuel rocket booster propellant.

“It is an uninformed, incompetent report compiled by people who know nothing about the plant, how it is operated or how materials are stored or handled there,” said Keith Rooker, executive vice president and general counsel for the company. “We think the evidence is clear that there had to be a pre-existing natural gas leak and gas fire.”

Clark County Fire Department Chief Roy Parrish has said the disaster was sparked by “spewing molten iron from an acetylene torch” being used by a worker hanging new siding on a building in which ammonium perchlorate was being processed.

But the union report, which was based on more than 40 hours of interviews with employees and hundreds of NDOSH documents, concluded that the explosion was triggered by a small fire that started in a batch dryer, which it described as a fiberglass-insulated machine used to dry newly crystallized ammonium perchlorate.

The fire soon spread to other flammable materials including several drums filled with a combustible mixture of ammonium perchlorate, ash and trash, the report said. Although only slightly flammable itself, the chemical will support rapid burning of nearly any combustible material.

Union Lists Factors

“The source of the fire is important to an understanding of the accident, but equally important are factors that caused the fire to spread, and allowed it to reach millions of pounds of explosive material,” the report said.

According to the report, those factors include improper storage of ammonium perchlorate, use of combustible materials in walls, roadways and insulation, lack of safety systems, poor maintenance, inadequate training of plant workers and lack of response to previous accidents.

“Chemical plant safety requires . . . measures that not only reduce the frequency of minor accidents, but confine those accidents to small areas of the plant where they can be brought under control,” the report said. Such measures “did not exist at PEPCON on May 4.”

“They are totally wrong,” said Charles Urban, a spokesman for the company. “The union knows zip-zero about ammonium perchlorate and zip-zero about manufacturing ammonium perchlorate.”

“In terms of us not knowing diddley-squat, it doesn’t take a mental giant to know they had a problem with storage of ammonium perchlorate,” argued James Valenti, a union safety expert who co-authored the report. “Our main concern was the lack of fire- suppression systems given the nature of the product the facility produced.”

Indeed, the plant had been inspected by NDOSH officials at least 11 times between 1980 and 1987. Four of those inspections resulted from accidents in the plant and five from worker complaints. Two others were follow-ups to previous inspections.

More recently, NDOSH cited the company for a host of safety violations and recommended a $36,455 fine in connection with the explosion that leveled the Henderson plant, said Mike Tyler, NDOSH administrator in Las Vegas.

The alleged violations include an absence of manufacturing controls, resulting in increased danger of fire, explosion or both; failure to develop emergency evacuation and response procedures, and failure to keep chemical storage areas free of combustible materials.

Tyler added, however, that a study conducted by an explosion expert from the U.S. Department of Labor, Mine Safety and Health Administration, was unable to pinpoint a cause for the explosion beyond a suggestion that “natural gas leaks may have existed in the plant.”

The plant, one of only two in the nation that processed solid rocket fuel, is being rebuilt at a 4,200-acre site in Cedar City, Utah. The company says it will resume production of ammonium perchlorate in June.