Reagan's path was blocked by a fire engine parked on a dirt road, so he guided his dozer onto a roadway that ran parallel to and above the first one. His new path required him to drive down a steep embankment to get back to the lower road and reach his assignment. Although he had identified a spot he felt would be safe, the report said, he instead steered his machine onto the lip of an 81 percent slope and started down.
A firefighter stationed at the engine on the lower road told investigators he saw Reagan's dozer slide down the slope. The bulldozer's blade struck the edge of the embankment, he said, causing the machine to roll onto its left side. The dozer eventually came into contact with the fire engine's rear bumper.
Reagan "was ejected from the cab and was pinned beneath the left sweep," the report states. Sweeps are sets of heavy bars meant to protect the operator's cab.
A paramedic who was nearby at the time pronounced Reagan dead.
The preliminary report on Reagan's death is not final. Cal Fire emphasizes that it was published in a short time frame and is subject to changes stemming from further investigation.
Cal Fire has pulled Reagan's employer from its rotation of as-needed contractors after learning that it may not have been providing workers' compensation insurance to its workers.
His death is believed to be the first of a bulldozer operator working a wildfire in California in nearly nine years. That last fatality, on Oct. 8, 2007, occurred within a mile or so of Reagan's accident.
Matthew Will, a Cal Fire heavy fire equipment operator, died of a head injury suffered when his bulldozer slipped off the side of a hill and rolled over at least twice. That incident, during a blaze dubbed the Colorado Fire, led to a lawsuit against the bulldozer manufacturer, Caterpillar Inc. Will's family alleged the vehicle was defectively and negligently designed. A jury awarded the plaintiffs $6.7 million in damages.
Reagan's employer, Czirban Concrete Construction, is one of hundreds of firms Cal Fire contracts with to provide bulldozers, water tenders and other equipment and services the agency needs each year.
The Contractors State License Board, which has suspended Czirban's license eight times in the last four years, launched a new investigation into the company this week after learning of Reagan's apparent employment there.
The firm has told the board that it had no employees and therefore did not need to provide worker's compensation, an agency spokesman said.
Cal Fire's contract with Czirban includes an insurance policy with the State Compensation Insurance Fund that expired in January 2015.
Cal Fire says it relies on its vendors to make sure their paperwork is up to date. If the agency learns that one of its as-needed contractors is not providing workers' comp, it can cancel its contract, an agency official said.
"The obligation remains with the contractor to comply with these requirements," Cal Fire spokeswoman Janet Upton said in an email. "We are currently investigating, and in the meantime, this vendor has been pulled from our rotation."