PORTLAND, Ore. (CN) - Environmentalists are fighting the U.S. Forest Service's plan to spray herbicides on more than 22,000 acres of streams, wetlands and forests in the Hell's Canyon and Eagle Cap Wilderness areas. The League of Wilderness Defenders/Blue Mountains Biodiversity Project claims the chemical attack on invasive plants will pollute rivers in violation of the Clean Water Act.
The Wilderness Defenders also claims the federal agency did not properly evaluate the damage the chemicals will cause.
The Forest Service plans to spray 22,804 acres of the Wallowa-Whitman National Forest, which covers 2.3 million acres in northeastern Oregon and western Idaho.
Most of the aerial spraying will happen in Hell's Canyon. The Forest Service plans to spray nearly 23,000 acres, including 6,345 acres of riparian habitat, with 10 chemicals, according to the compliant.
Much of that wild land provides habitat for endangered, threatened or sensitive fish such as steelhead trout, sockeye salmon, Chinook salmon, bull trout, redband trout and westslope cutthroat trout, the environmentalists say.
They claim the Forest Service did not consider the impact of spraying toxic herbicides into wetland areas in its environmental impact statement, though it acknowledged that many streams in the area to be sprayed are in "impaired condition," due to their temperature.
The Forest Service admitted that "all modeling scenarios for this project indicate that herbicides will reach streams and waterways at some level of concentration through drift, runoff or leaching," the lawsuit states.
But the federal agency never evaluated whether its plan complies with the Wallowa-Whitman National Forest Plan and the Pacfish/Infish amendments to the plan, the lawsuit states.
The League of Wilderness Defenders wants the spraying barred as violating the Wallowa-Whitman National Forest Plan, the National Forest Management Act and the Clean Water Act.
It is represented by R. Scott Jerger with Field Jerger and Tom Buchele with the Pacific Environmental Advocacy Center.
Read the Top 8
Sign up for the Top 8, a roundup of the day's top stories delivered directly to your inbox Monday through Friday.