Woods Cross » A pipe with hundreds of pounds of pressurized hydrogen suffered a "catastrophic failure" that started Wednesday's explosion at the Silver Eagle Refinery, a federal investigator said Saturday.
When the 10-inch pipe separated, hydrogen spewed to a furnace and ignited, said Donald Holmstrom, an investigations supervisor with the U.S. Chemical Safety Board. The force of a resulting fireball, combined with the 630 pounds of pressurized hydrogen, burst east toward homes in a Woods Cross neighborhood.
There were no injuries, but 10 homes suffered severe damage. At least one was blown from its foundation.
Holmstrom said investigators don't know why the pipe suffered what he called a "catastrophic failure." He told reporters Saturday the Safety Board will test what's left of the pipe to determine such possibilities as wearing, or if it was made of the correct materials.
Refineries are supposed to monitor the integrity of piping, and Holmstrom said his agency also will inquire whether that monitoring occurred at Silver Eagle.
"I can assure the people who live around this area that we will do a thorough investigation," Holmstrom said.
A spokeswoman for Silver Eagle said the company was unaware of the Safety Board news conference and could not provide comment.
The pipe was attached to a reactor that removes waxes from diesel fuel. The pipe normally carries diesel and hydrogen, but the Silver Eagle was performing maintenance at the time of the failure and only hydrogen was in the pipe, Holmstrom said.
The pipe is vertical then bends horizontally. Holmstrom said the failure occurred near the elbow on the horizontal section and spewed the 800-degree hydrogen east toward the neighborhood.