The U.S. Forest Service has backed off claims about the effectiveness of the huge red plumes of fire retardant that big airplanes drop on wildfires, but the agency does not expect to cut back on using it.
Acting under a court order, the agency Friday posted on its website the final environmental impact statement laying out how it plans to use fire retardant without harming threatened and endangered fish, wildlife and plants on national forests and grasslands covering 193 million acres in 44 states.
The Forest Service chief must sign the statement before it goes into effect, and the court timetable gives him until the end of December.
Forest Service analyst Glen Stein said that after it was pointed out the agency has no hard data showing fire retardant is effective, his team "softened" earlier claims about its effectiveness. But officials know from experience that it works and plan to keep using it, while taking steps not to harm endangered species.
The new plan slightly increases the amount of land designated as off-limits to retardant drops to protect the environment. It only allows drops in those buffer zones to protect human life and eliminates past exemptions to protect property.
"This is going to be more about where we may or may not use it," Stein said. "It's not really about quantity of use."
"We have a word for that: faith-based firefighting," said Andy Stahl, director of Forest Service employees for Environmental Ethics. The watchdog group prompted the analysis through federal lawsuits dating back to 2003 challenging the use of chemical fire retardant, primarily because it kills fish when it lands in streams and lakes.
Stahl said it was immoral to ask pilots to risk their lives dropping retardant from big planes if there was no scientific evidence it was effective.
"It's also bad for the environment, gets into creeks and critical habitat, kills fish and threatened and endangered species. Third, it is expensive," he said.
The agency reports that fire retardant is only used on 5 percent of the wildfires that start each year, costing $24 million to $36 million a year of the nearly $1 billion spent annually fighting wildfires. There were 36,000 retardant drops from 2000 through 2010, using more than 90 million gallons of the substance.
Stein said a study in the 1980s tried to quantify how effective fire retardant was when used to attack small fires, keep fires from growing, and protecting homes, but researchers determined there were too many variables to consider to make any conclusions.
Since 2000, about 30 percent of the national forest land base has been designated as buffer zones to protect rivers and lakes. New buffer zones to protect endangered plants and animals on land, such as butterflies, add less than 1 percent.
The Forest Service has just finished new maps for all national forests laying out the buffer zones so firefighters can see whether an area is open to retardant drops before calling for them.
In 2008, the analysis said, 11 accidental drops were made in excluded zones, and one under an exemption. There were 22 accidental drops and two under exemptions in 2009, and there were 16 accidental drops and 51 under exemptions last year.