Federal agency says fatal Fremont explosion was preventable

A federal agency on Wednesday called the fatal July explosion at a Fremont industrial facility, “a terrible tragedy,” that it said was completely preventable.

The U.S. Chemical Safety and Hazard Investigation Board said the July 29 explosion and fire at Horizon Biofuels, which resulted in the death of a worker and his two young daughters, was caused by a “completely avoidable hazard.”

“This terrible tragedy should not have happened,” CSB Chairperson Steve Owens said in a news release. “Preliminary evidence points to a combustible wood dust explosion, a well-known – and completely avoidable – hazard in wood processing.”

The agency, an independent, nonregulatory federal agency charged with investigating incidents and hazards involving the catastrophic release of extremely hazardous substances, provided an update on its investigation, which has not gotten very far because it still has been unable to access the building.

“At the time of this update, the Horizon Biofuels facility remains unsafe and officials have advised that people maintain a safe distance from the facility due to the potential for the structurally compromised building to collapse, preventing the CSB from approaching the building so far,” the agency said in a preliminary report.

It did, however, provide some details about what happened that day.

The explosion occurred shortly before noon, “following a sudden release of dust or smoke from the tower, quickly followed by flames and a much-larger, major blast that caused significant structural damage,” the report said.

32-year-old Dylan Danielson was working in the plant at the time and was killed in the explosion, as were his 8- and 12-year-old daughters, who were at the plant waiting for their dad to get off work to take them to a medical appointment.

According to the CSB report, Danielson initially survived the blast but was trapped. He spoke via phone to both the plant manager, who was working from home, and his wife.

Workers from neighboring businesses reported that they heard Danielson calling for help and entered the building to attempt to rescue him but were prevented from doing so because of the condition of the facility.

Once emergency personnel arrived, they evacuated everyone from the scene because of the continuing fire and risk of collapse. They were not able to access the structure until the following day, at which point they retrieved the three bodies.

The CSB said its investigation will focus on the operations and conditions at the Horizon Biofuels facility, as well as dust-control systems, industry guidance for safe dust operation and regulatory oversight. A combustible dust explosion can occur when certain conditions align at a facility, including dust accumulation, dispersion and ignition within a confined space, potentially triggering a powerful secondary explosion, like the one that occurred at the Horizon Biofuels facility.

The CSB previously has investigated a number of combustible dust incidents across industries. Additionally, in 2006 it issued a major study of combustible dust incidents involving 281 dust explosions that resulted in 119 deaths and 718 injuries.

According to Occupational Safety and Health Administration records, Horizon was cited in 2012 for four violations that were deemed "serious," and was fined a total of $6,000.

The Nebraska State Fire Marshal’s Office, which is leading the state-level investigation, also attributed the blast to an “accidental dust explosion” in a preliminary report. The office could not immediately be reached for comment Wednesday afternoon.