UPDATE 1-Natural gas well burst kills one, injures three in Colorado

By Keith Coffman

DENVER Aug 15 (Reuters) - A high-pressure burst of natural gas at a well operated by Canadian energy giant Encana Corporation in Colorado killed one man and injured three other workers on Wednesday, the company and local authorities said.

The accident at the well in Platteville, Colorado, about 30 miles (48 km) northeast of Denver, apparently resulted from an equipment failure, said Weld County Sheriff's Office Sergeant Tim Schwartz.

"It appears to be an industrial accident and doesn't look like anything suspicious," he said, adding there was no explosion or fire.

A 60-year-old worker was killed and three other workers were hospitalized with non-life-threatening injuries, Schwartz said.

The precise cause of the "high-pressure gas release" is under investigation, said Wendy Wiedenbeck, a Denver-based spokeswoman for Encana.

Two of the three injured workers and the man who was killed were Encana contractors, Wiedenbeck said. The third injured victim was a company employee. Their names were not immediately disclosed.

The fatal burst of natural gas occurred after the drilling of a horizontal gas well had just been completed and workers were in the process of putting the well into production, Wiedenbeck said.

Additional circumstances of the accident were not immediately known, but no adjacent facilities were damaged, she said.

"The location and well are secure," she said. "Our thoughts and prayers go out to the families and friends of our colleagues."

The well is one of about 1,100 oil and gas wells operated by Encana in a fossil fuel-rich region of eastern Colorado known as the Denver-Julesburg Basin. Encana, headquartered in Calgary, is one of North America's leading producers of natural gas.

Wiedenbeck said Wednesday's accident marks the first fatality for Encana in the basin.

The accident comes amid heightened scrutiny of the oil and gas industry sparked by accelerated onshore energy development in recent years coinciding with the advent of hydraulic fracturing, or fracking.

The production-boosting technique involves the injection of large amounts of water, chemicals and sand into underground rock formations to force the extraction of hydrocarbon fuels that would otherwise be inaccessible.

The company typically employs fracking in its horizontal wells, but "this was not a hydraulic fracturing accident," Wiedenbeck said.

"That part of the operation (fracking) had already been completed" as part of the well-drilling work that was performed before the well was being placed into production, she added.