Calif. Fire Retardant Drop Likely Killed Utah Firefighter
Aug. 21—A 42-year-old Utah firefighter who died battling the Mendocino Complex Fire last week may have been killed after a massive retardant drop from an air tanker broke apart trees and he was struck by the debris, according to a preliminary Cal Fire report.
At about 5:35 p.m. on Aug. 13, a Very Large Air Tanker, one of Cal Fire's converted DC-10s or Boeing 747s, dropped a retardant load along Division C of the Mendocino Complex Fire in Mendocino County. Battalion Chief Matthew Burchett was killed by tree debris and three other firefighters received minor injuries, according to the report.
The incident was serious enough that Cal Fire issued recommendations for "immediate corrective actions."
"Fire line personnel must remain clear from areas being impacted by aircraft retardant/water drops with overhead hazards," the report stated.
The three-sentence preliminary report did not provide any more details on the event. Cal Fire spokesman Scott McLean said no further information could be released and a more thorough report would follow that likely would provide a more definitive cause of Burchett's death.
The retardant drop came from the big guns in Cal Fire's air fleet—either a DC-10, which carries up to 12,000 gallons of fire retardant, or a 747, which carries up to 24,000 gallons. Fire retardant is made up of water, fertilizer, or ammonia phosphate, and some type of chemical to give it the signature and highly visible red coloring.
Mark Grissom, a wildlands firefighter since the 1990s, said he's never seen a fire retardant-related injury, but he has seen the tops of trees explode as the heavier-than-water slurry hits the canopy.
"It was bound to happen," Grissom said. "If you drop a full load of retardant at a low drop point and it's still a solid mass it's gonna blow the (expletive) out of the tops of trees."
Many of the larger planes simply drop the retardant out of the belly of the plane and the liquid mixture falls to the ground at the same speed as the planes, which can be 250 to 300 mph. Add to the equation drought-weakened or dead trees and Grissom said it can be a hazard.
Planes must fly low to make sure the retardant hits the ground, adding wind from the aircraft to the trees and a thicker consistency to the retardant when it hits the foliage.
Some planes have drop systems that allow them to spray the retardant, which slows it down almost like a fine rain, but it's unknown if the aircraft that day had such a system.
Ground firefighters receive radio warning of an impending drop, Grissom said, before a lead plane makes a warning pass, and before returning for a second pass followed by the drop aircraft.
"The guys in the aircraft can't see people on the ground," the wildland firefighter veteran said. "But it's not uncommon. I've seen many limbs broken. It does not take a lot. It's best to get out of the way when the lead plane makes the first path."
What no one argues is the importance of retardant drops.
"It's used on the fire's edge to impede progress. To give a chance for the ground troops to catch up," McLean said. "Or it can be dropped on the fire to cool it down."
