EUGENE, Ore. — A federal judge said environmental advocates face “an uphill battle” in their attempt to block commercial thinning on 29,000 acres in Oregon’s Fremont-Winema National Forest.

The Oregon Wild and Wildearth Guardians nonprofits asked U.S. District Judge Michael McShane to halt three thinning projects, arguing the U.S. Forest Service didn’t analyze their environmental consequences as required by the National Environmental Policy Act.

The plaintiffs claimed the scale of these projects — which intend to restore forest health and wildlife habitat — exceeds what’s permissible under a “categorical exclusion” that exempts certain federal activities from NEPA environmental studies.

“NEPA doesn’t go to the purposes of a project, it goes to its impacts. Commercial thinning comes with some trade-offs. It comes with significant negative impacts,” said Erin Hogan, attorney for the environmental groups, during oral arguments July 20 in Eugene, Ore.

If the Forest Service properly approved the South Warner, Bear Wallow and Baby Bear thinning projects under “categorical exclusion 6,” which applies to restoration activities, then the agency’s exemption itself is unlawfully broad, she said.

Commercial logging of such a magnitude cannot proceed without at least a NEPA assessment of environmental effects on which the public can weigh in, Hogan said.

“It has to make those findings and it has to support them. In this case, the Forest Service did not make the requisite findings,” she said.

However, the judge said it’s an “uphill battle” to argue three projects don’t pass muster under NEPA, citing a legal precedent in the 9th U.S. Circuit Court of Appeals for the same type of exemption.

“You’re still stuck with a 9th Circuit decision that commercial logging is appropriate under CE 6,” McShane said.

A formal ruling could possibly be issued next month.

The plaintiffs claimed that case law pertains to thinning on 600 acres, while the challenged projects entail much more extensive logging, but the judge appeared skeptical of this argument.

“Is it really the court’s role to step in and decide the scope of a thinning project?” asked McShane, adding that he was an English major while the projects were developed by agency scientists.

Attorneys for the federal government and timber industry argued it’d be inappropriate to impose a specific size limit on thinning projects approved under the exemption.

However, categorical exclusion 6 does place constraints on thinning projects, which must involve forest stand or habitat improvement and cannot use herbicides or build more than a mile of road, said Sean Martin, attorney for the Forest Service.

“It’s not limitless. It has to be a restoration project,” he said.

The projects in question involve dry forests that don’t include threatened or endangered species, such as the spotted owl or sage grouse, Martin said.

“The Forest Service would run into problems if it relied on CE 6 in a different ecological landscape. It depends on the contours of a specific project,” he said.

Thinning can make a “striking” difference when wildfire spreads onto overcrowded stands, which can end up “toasted” without restoration treatments, Martin said.

“We want to get ahead of a fire rather than deal with the aftermath,” he said. “I don’t think it’s arbitrary to want to get ahead of that.”

While the plaintiffs only oppose the commercial aspects of the three projects, thinning is done in conjunction with prescribed burning and other treatments, Martin said.

“If you were to just set aside commercial thinning, that would pretty much gut this project,” he said.

The government’s position was bolstered by the American Forest Resource Council, which is involved in the litigation as an “amicus” or “friend of the court.”

“Each project here is carefully designed to improve timber stand health and wildlife habitat,” said Sarah Melton, AFRC’s attorney.