Last January, Randy Yellowman died in an explosion while working at a natural gas well pad south of Durango, and one year later, it appears investigators will never know what ignited the flare-up that caused his death.

Yellowman, a 47-year-old Native American man who lived in a small community between Farmington and Shiprock, New Mexico, was working as a contracted truck driver and was alone at the time of the explosion. His body was found later in the day by ranchers.

According to pages of documents obtained in an open records request, investigating agencies have been stumped as to what ignited the explosion that day – Jan. 2, 2019. And what has further perplexed the investigation is that Yellowman had been working the job for 17 years.

So why, on this day, did things go so terribly wrong?

“It’s the craziest thing I’ve ever seen,” said an on-scene investigator, the day after the explosion.

Yellowman’s death, however, has not come without consequences.

This summer, the U.S. Department of Labor’s Occupational Safety and Health Administration fined Yellowman’s employer, Farmington-based Overright Trucking Inc., more than $10,000 for safety violations and procedural failings that likely led to his death.

In December, Colorado’s top oil and gas regulators issued a notice of violation to the Catamount Energy Partners LLC, the Denver-based company that owned the well pad, which could result in thousands of dollars in violations.

And, Yellowman’s family has brought a wrongful death lawsuit against the company that built the tank – American Manufacturing Equipment, based in Farmington – seeking compensatory and punitive damages.

The companies involved in Yellowman’s death either did not return calls or declined to comment.

Around 7:30 a.m. Jan. 2, 2019, Yellowman arrived at a well pad about 6 miles west of Ignacio, just off an unnamed road near County Road 318, which lies within the massive San Juan Basin natural gas field that extends from Southwest Colorado to northern New Mexico.

When natural gas is extracted from thousands of feet beneath the surface of the Earth, the process also brings up groundwater, which is stored on-site in tanks. The liquid – referred to as “produced water” – can contain oil, hydrocarbons and a range of potentially flammable compounds.

Yellowman’s job that day was to transfer the produced water from the storage tank to his truck, a routine procedure. He was nearly finished, investigators say, when the tank exploded.

Yellowman was launched from the tank and killed instantly, according to investigators, with his body found a few feet away near his truck. The water tank was strewn hundreds of feet away in a field.

Around 11 a.m., two local ranchers came upon the scene. They found Yellowman and called 911.

Because the well pad is on private land within the jurisdictional boundaries of the Southern Ute Indian Tribe, tribal police were first on the scene. But Lindsay Box, a spokeswoman for the tribe, said the explosion was not on tribal trust land and did not involve the tribe or a tribal member.

“For that reason, the tribe has not taken the lead in investigating the accident but has assisted state agencies when necessary,” Box said.

OSHA and the Colorado Oil and Gas Conservation Commission, which oversees oil and gas production in the state, took over the investigation.

In an open records request to OSHA, however, all of the Southern Ute tribe’s investigation, including an autopsy report, were redacted. Box did not respond to a request seeking these documents.

The day after the explosion, investigators with OSHA and COGCC scoured the scene, looking for clues.

The tank on Yellowman’s truck was nearly full, indicating he was almost done with the transfer. The truck itself appeared in good working order. And Yellowman, who was considered “very experienced” by his bosses, had visited the site on a daily basis.

Transferring produced water is inherently risky business, however. Tanks that store produced water hold the risk of exploding because of the vapors that exist inside the tank between the produced water and the top of the tank.

Investigators know why the explosion happened. What they don’t know is what ignited it.

“The scarcity of information as to the operator’s actions on-site were a contributing factor in the lack of a conclusion,” OSHA wrote in its report.

The only evidence found at the scene that was slightly out of the ordinary was a handheld torch that belonged to Yellowman. But according to Overright policy, no torch work is allowed at well pads, and if the need arises, say, to unfreeze a valve, employees are required to call in any non-routine work.

“A lot of things don’t add up to me,” Brad Smith, Yellowman’s supervisor with Overright, told investigators in June.

While an ignition source hasn’t been pinned down, investigators did find a number of failings with the companies that at least played a part leading up to Yellowman’s death.

OSHA, in fining Overright, said the company did not properly train its employees to protect themselves from potentially explosive situations, or even put up signage about the risks. Yellowman’s truck, too, was not grounded to dissipate the potential buildup of static electricity that happens during fluid transfers, something Smith told investigators is not company policy.

“It is inconclusive that these conditions were direct factors in the explosion, however, they are protections that would have offered protection to the employee,” OSHA wrote.

Overright, which has been in business since 1991, was fined $10,608.

The COGCC, in its investigation, which is pending, said Catamount Energy also failed to adhere to proper safety protocols. Tanks were not properly labeled with fire danger warnings, the site was strewn with debris and Yellowman should have been instructed he was not allowed to have a personal hand torch.

State regulators ordered Catamount Energy to completely re-evaluate its fire safety procedures. Yet investigators have expressed concern: By not knowing what ignited the blast, how can a similar situation be prevented in the future?

“At this point, all the agencies can do is make sure rules are in place to help prevent future occurrences,” said Megan Castle, a spokeswoman with COGCC.

Yellowman’s family declined to comment for this story.

His father, Gary, however, did retain the Albuquerque law firm Guebert Bruckner Gentile P.C., which filed a civil lawsuit against the company that made the tank, American Manufacturing Equipment, saying the tank failed to meet standard safety guidelines.

“The tank did not meet standards that would have allowed a release of a buildup of pressure,” said attorney Terry Guebert. “Had it been built properly, it would have released pressure. But instead, it shot off there like a rocket and killed him.”

The law firm maintains that because American Manufacturing Equipment’s tank was not properly built, the tanks venting system froze, and allowed for a dangerous buildup of combustible fumes. And, Guebert said there is still a chance to find the ignition source: Private investigators with the law firm are searching for clues.

OSHA did not provide data about how many oil and gas workers have died in Colorado in recent years. According to Herald archives, a blast at a BP American Production Co.-owned gas compression station near Bayfield in 2012 killed one worker, Mancos resident Randy Mathews, and injured two others.

Nationwide, a total of 1,422 workers died from injuries in the oil and gas industry from 2003 to 2015, according to federal data. In 2017, deaths in oil and gas and mining and quarrying increased 26% from the year before, totaling 112. Oil and gas accounted for more than 70% of those fatalities.

Yellowman was born in Shiprock, and most recently was living in Nenahnezad, a community on the Navajo Nation between Farmington and Shiprock. His family’s lawyers said any costs recouped in litigation would go to his two minor children, who now live with their grandfather.

jromeo@durangoherald.com