A criminal jury trial in Denver began on May 31 against Xcel Energy Inc., Minneapolis, and its local subsidiary Public Service Co. of Colorado, over a combined 10 federal safety violations that led to five worker deaths on Oct. 2, 2007.

Five painters, ranging in age from 19 to 52, died when they were overcome by carbon monoxide when a fire erupted while they were spraying an epoxy coating sealant inside a 12-ft-dia., 4,000-ft-long water drainage pipe, or penstock, at an Xcel facility. The accident occurred at the 44-year-old, 1.2-MW Cabin Creek hydroelectric plant, located 35 miles west of Denver.

A malfunctioning epoxy sprayer system had prompted crews to clean hoses using methyl ethyl ketone. Vapors from the flammable solvent, housed inside the sprayer base, ignited a chemical fire. Flames blocked the only viable exit inside the penstock at the lower end, leaving workers trapped 1,500-ft underground.

Gary Foster, Don DeJaynes, Dupree Holt, Anthony Aguirre, and James St. Peters survived for about one hour before dying of asphyxiation from carbon monoxide inhalation. Four additional workers on the opposite side of the fire escaped.

The nine-man crew worked for Santa Fe Springs, Calif.-based RPI Coating Inc., a 29-year-old firm with $20 to $50 million in estimated annual revenue. RPI and company executives Philippe Goutagny and James Thompson were also indicted. Their trial date has yet to be set.

In 2008, the U.S. Occupational Safety and Health Administration fined the contractor and owner $1 million for safety violations. About 82% of those penalties were assessed against RPI for using unsafe electrical equipment, improperly handling flammable liquids, providing inadequate ventilation and not having an emergency response system in place, among other things.

A 2009 grand jury decided that criminal charges were warranted, a rare occurrence for OSHA violations. If convicted, the firms could have to pay fines of up to $2.5 million each.

Unlike RPI, no Xcel or Public Service executives are being tried. However, criminal prosecution brings the possibility of strict post-conviction supervision and large penalties than a civil action.

Predictably, opening oral arguments have attorneys pointing fingers at each other. The prosecution, led by Jaime Pena of the Denver-based U.S. Attorney's Office’s Healthcare Fraud Task Force, claims Xcel picked the cheapest bid and ignored plant safety problems. The defense, represented by Cliff Stricklin of Holme Roberts & Owen LLP, counters that Xcel fulfilled its legal safety obligation and that RPI is responsible.

A 200-page report released last year by the U.S. Chemical Safety and Hazard Investigation Board levels blame at both owner and contractor, citing “a lack of planning for hazardous work, inadequate contractor selection and oversight, and insufficient regulatory standards.”

This is a longer version of the story originally posted on June 9, 2011.