BOULDER, Colo. — The most destructive wildfire in Colorado history started with a dormant blaze burning on a religious group’s property and was fed by a second fire believed to have been sparked by Xcel Energy equipment, according to a report released Thursday by the Boulder County Sheriff's Office and District Attorney's Office.
Boulder County Sheriff Curtis Johnson and District Attorney Michael Dougherty announced the results of the nearly 18-month investigation into the cause and origin of the Marshall Fire during a news conference Thursday morning.
No criminal charges will be filed in the fire, which destroyed more than 1,000 homes and killed two people. The wildfire erupted late the morning of Dec. 30, 2021, and was fueled by hurricane-force winds as it raced across the county.
"With every home that burned that day, people lost everything," Johnson said at the news conference. "All their possessions, family heirlooms turned to trash. I share that loss because I lost my home to the Marshall Fire. And if you give me a little grace, I get emotional still about the impact that has had on my family."
The investigation did not find that a long-smoldering underground coal fire, burning in the area since the 1860s, played a significant role in the fire’s eruption. Johnson said the coal fire's involvement cannot be completely ruled out as a source of the second fire, which started near the Marshall Mesa Trailhead.
"If we were to tell you today we were filing charges, it would be wrong and unethical," Dougherty said. "We can only file charges when there's evidence of a crime having been committed. [...] A judge would dismiss this prosecution for lack of evidence."
Although no criminal charges will be filed, the investigation could spark civil litigation.
> Watch the full news conference below:
The investigation concluded that an intentionally set trash fire on property owned by a religious group known as Twelve Tribes was the initial point of origin for the Marshall Fire.
That fire, reported a little before noon Dec. 24, 2021, included the burning of railroad ties. A passer-by reported the fire, and both Mountain View Fire Rescue firefighters and Boulder County Sheriff's Office deputies responded. Because people from Twelve Tribes had water and a tractor on scene, firefighters were not concerned and left.
One Boulder County Sheriff's deputy told people tending the fire that they should cover it with dirt when they were finished burning. However, it appears that embers from the fire smoldered until hurricane-force winds roared through the area six days later and re-ignited the fire, according to the investigation.
That occurred around 11:20 a.m. Dec. 30, 2021.
WATCH: Marshall Fire caused in part by reignited fire on religious land
"A high-wind event uncovered the previously covered fire, and the embers were exposed to oxygen and blown into the nearby dry vegetation," Johnson said. "The vegetation caught fire and began to quickly spread through the property."
"The residents of that property were initially unaware of the fire that began, and once they realize there was a fire and that it was spreading, they attempted to put it out, but the winds were quickly spreading the flames faster than they could keep up," Johnson said.
Johnson said that a shed on the property that was widely seen in videos that captured it burning was not on fire when first responders arrived.
"That shed was initially investigated as a potential location for where the fire started," Johnson said. "But after our investigators exhumed and re-created the remains of the shed, we learned there was no electrical service to the shed and no indication the fire started at that location."
Photos: Marshall Fire investigation
Dougherty said there's no indication the residents at that property created a substantial or unjustifiable risk when they lit the fire on Dec. 24 and that firefighters who responded to reports of the fire did not find any issues.
"They determined, Mountain View Fire did, that the fire, the way it had been set and their plan to extinguish it was reasonable and responsible," Dougherty said.
Dougherty also said there's no evidence the residents set a fire on Dec. 30.
Roughly 40 minutes after that fire ignited, a second blaze began nearby, sparked by hot particles discharged from an Xcel Energy power line at the Marshall Mesa Trailhead, the investigation found.
"A close examination of the power lines in the area revealed that one of the power lines had become unmoored from a cross-arm and was hanging low enough to come into contact with a support brace," Johnson said.
An outside electrical engineer and wildfire expert determined that the power lines showed evidence of a significant amount of arcing.
"The arcing of the power lines produced hot aluminum particles, which were then discharged into the receptive fuels below the powerline," Johnson said.
The expert determined it was more likely than not that the second fire was caused by the discharged particles, according to the investigation.
The unmoored power line was not recognized during the initial inspection by investigators because it was quickly reattached to the cross-arm by Xcel in an effort to restore power to the area.
Dougherty said Xcel won't face charges because investigators did not find any evidence of criminally negligent system design or maintenance with the equipment and wiring in that area.
Dougherty also said there's no evidence Xcel tried to cover up the power line's role in starting the fire when it repaired the line.
"The snow was coming down, it was freezing cold, people were without power, pipes were freezing, people were concerned they would be driven out of the homes that were still standing," Dougherty said. "There were demands that the power be put back on, including from law enforcement."
"There's no evidence at all that they repaired the line in an effort to impede the investigation or hide something from criminal or civil proceedings," Dougherty said.
Johnson said investigators looked into the possibility that embers from the first fire started the second fire, but they ruled it out due to its location.
"Given the fact that the second fire was approximately 2,000 feet south and west of the first fire, investigators determined it was not likely embers moved that far against the wind and started the second fire," Johnson said.
WATCH: Xcel Energy disagrees its power line could be cause of Marshall Fire
Xcel released the following statement after the investigation's conclusions were announced:
"Our thoughts are with the families and communities impacted by the devastating wildfire in Boulder County. We agree with the Boulder County Sheriff’s Office report that the Marshall Fire started as a result of an ignition on a property (5325 Eldorado Springs Drive) previously reported to be affiliated with an entity called the Twelve Tribes, and that this ignition had nothing to do with Xcel Energy’s powerlines.
"The Sheriff’s report cites several potential causes for a second ignition near the Marshall Mesa Trailhead that started roughly an hour after the first fire. We believe the second fire burned into an area already burned by the fire from the first ignition, and did not cause damage to any homes or businesses. We strongly disagree with any suggestion that Xcel Energy’s powerlines caused the second ignition, which according to the report started 80 to 110 feet away from Xcel Energy’s powerlines in an area with underground coal fire activity.
"Xcel Energy did not have the opportunity to review and comment on the analyses relied on by the Sheriff’s Office and believes those analyses are flawed and their conclusions are incorrect. We have reviewed our maintenance records and believe the system was properly maintained. We operate and maintain our electric system consistent with leading energy service practices and we’re proud of our employees and the work they do to deliver safe, reliable and clean energy to our communities. As members of the Boulder community, we will continue to support our neighbors in this recovery."
> Contact 9Wants to Know investigator Kevin Vaughan with tips about this or any story: kevin.vaughan@9news.com or 303-871-1862.
SUGGESTED VIDEOS: Marshall Fire Coverage
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