(CN) - The 9th Circuit on Tuesday refused to take another look at its decision to require logging companies to get permits for the mud and sediment that washes off logging roads and into forests and rivers.
Last year, a three-judge panel in Portland, Ore., had reversed a federal judge's that said storm runoff is exempt from federal regulations on water pollution.
The Portland-based Northwest Environmental Defense Center sued a group of Oregon timber companies for not having permits for storm water that runs off logging roads and into a system of ditches and culverts, ultimately getting dumped into the Tillamook State Forest and its rivers and streams.
U.S. District Judge Garr King dismissed the challenge, deeming the runoff exempt from the national permit process by 1987 amendments to the Clean Water Act.
In its reversal, the 9th Circuit panel explained that the logging roads constitute a pollution "point source," thus triggering the Clean Water Act's permit requirements.
"We therefore hold that the 1987 amendments to the CWA do not exempt from the [national] permitting process stormwater runoff from logging roads that is collected in a system of ditches, culverts, and channels, and is then discharged into streams and rivers," Circuit Judge William Fletcher wrote for the three-judge panel.
"This collected runoff constitutes a point source discharge of stormwater 'associated with industrial activity,'" as defined by Congress, the court concluded.
The ruling applies to Oregon, Washington, Arizona, California, Nevada, Idaho and Montana.
Tuesday's order denies the petition for rehearing and rehearing en banc by timber companies and members of the Oregon Board of Forestry.
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