The U.S. Forest Service released the results of investigations into 2022’s Cerro Pelado fire that indicates a winter slash pile burn reignited to cause the blaze that charred more than 45,000 acres in northern New Mexico near Jemez Springs.

The Cerro Pelado Lookout alerted the Santa Fe Interagency Dispatch Center of billowy blue-gray smoke moving east in the strong winds shortly after 3:30 p.m. on April 22, 2022. 

The high winds caused the fire to grow quickly and, within a matter of hours, the blaze had engulfed more than 400 acres.

Firefighters spent the next two weeks battling the wildfire, which destroyed three houses and several non-residential buildings while also damaging Jemez Mountains Electric Co-Op infrastructure. One of the firefighters received minor injuries in the effort.

Two investigations into the source of the Cerro Pelado Fire came back with the same conclusion: the fire originated at an ash pit from a slash pile burn.

A slash pile is where debris such as stumps, cut brush and other woody debris are stacked and then burned.

The investigations were performed by the Washington State Department of Natural Resources and the U.S. Department of Agriculture’s Forest Service Law Enforcement and Investigations criminal investigators.

In February of 2022, the Jemez Ranger District of the Santa Fe National Forest ignited piles of debris as part of a slash pile burn initiative. The investigator for Washington began searching for the cause on April 28, 2022.

On April 29, 2022, the investigator visited the slash piles and found one of the piles contained heat below its surface.

“I continued to excavate the slash pile by hand and uncovered about 10 shovels full of smoldering charcoal. When this material was exposed to the wind, it readily ignited and burned with open flame,” the investigator, whose name is redacted in the report, wrote.

The investigator found that the slash piles had recently been disturbed, but could not conclude whether fire crews had been working the slash piles prior to the Cerro Pelado starting or if that work was done after the blaze ignited.

The investigator then conducted interviews that revealed fire crews had checked the slash piles as recently as April 20, just two days before the Cerro Pelado fire ignited, as well as during the time when the crews were trying to suppress the wildfire.

The investigator also documents the efforts to rule out lightning, cigarettes and recreational campfire as potential causes.

“This investigation recommends a review of policy, procedure, and practices associated with RX burning, slash pile location, and subsequent slash pile inspections,” the investigator wrote.

The fire began following several days of red flag conditions and, the morning that the fire sparked, the Santa Fe National Forest implemented burning restrictions.

A Forest Service engine captain who was out with his crew hanging signs informing the public about the restrictions later told the Forest Service investigator that his vehicle was being pushed back and forth by the wind that day.

A firefighting crew from Bandelier National Monument was the first to arrive on scene and quickly made the decision to focus on evacuating people from the area due to the extreme fire conditions and the weather.

The investigator determined that the high winds likely exposed the ash berms and, once exposed, those smoldering materials within the berms reignited.

According to the investigation, slash burn piles can hold heat months after the prescribed burning occurs and, if exposed again, that heat can lead to fires.

The winds likely blew the embers from the reignited piles onto dry vegetation upslope.

Both U.S. Senators Ben Ray Luján and Martin Heinrich, Democrats representing New Mexico, decried the Forest Service’s role in the fire.

“Today’s news that yet another wildfire in NM was started by (the U.S. Forest Service) is unacceptable,” Luján said in a tweet on Monday. “The Cerro Pelado Fire endangered New Mexicans. This was extremely reckless. There’s technology to detect these mishaps from occurring and USFS must do better to ensure this never happens again.”

Heinrich expressed frustration at learning that Forest Service prescribed burning practices led to another fire.

The Forest Service has previously taken responsibility for last year’s Hermits Peak and Calf Canyon fires, which joined and formed the largest wildfire in state history. The Hermits Peak fire was started by controlled burns during the spring while the Calf Canyon fire was caused by reignition of slash burn piles.

Heinrich said in his statement that climate change makes these fires more likely to occur and said the federal agency should keep that reality in mind when doing prescribed burns.

“The warming climate is making our forests more vulnerable to catastrophic wildfires. That’s a reality that our Forest Service can and must urgently respond to when deciding when and how to do prescribed burns. We cannot catch up to this reality if it takes nearly a year to even make the findings on the Cerro Pelado Fire public,” he said.

Heinrich also said the Forest Service needs to take actions to regain the public’s trust.

“This will require more transparency and much more concerted and authentic engagement with New Mexicans than the Forest Service has shown up to this point,” he said.

The Forest Service’s role in the Hermits Peak/Calf Canyon fire led the state legislature to pass a law prohibiting spring burning under certain conditions.

“I am – again – outraged over the U.S. Forest Service’s negligence that caused this destruction,” Gov. Michelle Lujan Grisham said in a statement. “While climate change and extreme drought continue to plague the Southwest, the Forest Service must abandon their business-as-usual approach to prescribed burns and forest management in our state. I am relieved to hear that the Forest Service will now use technology to prevent this from occurring in the future. We will continue to hold the federal government accountable for each of the disastrous fires they caused in our state last summer.”