According to a U.S. Occupational Safety and Health Administration document, a 2-inch metal pipe fitting blew off a valve and hit an employee in the head, killing him.
The Weld County Sheriff's Office identified the worker who died as Matthew Smith, 36, of Broomfield. Two other workers, Thomas Sedlmayr, 48, and Grant Casey, 28, were injured during the explosion at the fracking site at Highway 66 and Weld County Road 9 1/2. The workers were employees of Halliburton.
In the citation issued on May 12, 2015, OSHA said, "[Halliburton] did not furnish employment and a place of employment which were free from recognized hazards that were causing or likely to cause death or serious physical harm to employees in that employees were exposed to struck-by hazards associated with working in the red zone of the [gas] well."
"Red zones" are hazardous areas that have to be clear of workers when fracking pumps are operating, according to the industry publication, EnergyTrendsInsider.com.
"The employer did not ensure employees were protected from struck-by hazards associated with the removal of an ice plug from within" an assembly of valves, known as a "Christmas tree," the OSHA document said.
"Employees remained in the red zone while equipment was pressurized up to 3500 psi [pounds per square inch]. This condition exposed employees working in the red zone to struck-by hazards as a result of an explosion," the OSHA report said.
In "abatement notes" on how Halliburton should reduce well-site hazards, OSHA said, "Frozen plugs should be allowed to thaw at a normal rate. Steam or hot water should not be used to thaw plugs…Freezing operations should be under the direct supervision of a qualified person."
OSHA also said "proper steps should be taken to remove pressure" in the pipeline.