GREEN RIVER - A federal judge has ruled that a controversial oil and gas seismic survey project will be allowed to proceed in the Adobe Town area of southwest Wyoming's scenic Red Desert.

Conservationists and Bureau of Land Management officials said a recent ruling by an administrative appeals judge lifted a previous halt of the Cherokee West 3D seismic survey project.

Tom Foertsch, a physical scientist with the Bureau of Land Management's Rawlins Field Office, said in a phone interview Monday the agency was pleased with the ruling. "We're happy … All the issues were resolved to our satisfaction," he said.

But conservationists decried the decision and said the project could threaten fragile desert landscapes.

"We'll be examining all the legal options to get a better solution to the problems posed by this projects," said Erik Molvar, a wildlife biologist with the Laramie-based Biodiversity Conservation Alliance.

The project was proposed by Kerr McGee Corp. along with contractor Veritas DGC Land Inc. in March 2005.

Foertsch said due to the court "stay," however, Veritas has since dropped out of the project. He said the Houston-based Global Geophysical Services Inc. will now conduct the project.

"They filled out a new notice of intent to start the project last week, and we're looking at it and checking to make sure their proposal is identical to what we analyzed in our previous environmental work," he said.

The two companies want to search for pockets of natural gas in a 164-square-mile area in the southern Red Desert, including the Kinney Rim area in Sweetwater County and the Powder Rim area on the Colorado border.

The companies plan to use vibroseis vehicles, sometimes called "thumper trucks," and the shot-hole method for the survey. Using data from the shock waves, the companies are able to determine oil and gas resources underground.

Shot-holes will be drilled from buggies and from helicopter portable drills when the terrain dictates. Receiver cables for the project will be laid across the Adobe Town wilderness study areas as part of the project, according to plans.

Operators plan to use existing roads and trails, but cross-country travel via ATVs will be required in some instances.

Conservationists last year challenged the BLM's environmental documents approving the project in an appeal with the Interior Board of Land Appeals, which is an administrative court within the U.S. Department of the Interior. The appeal alleged violations of the National Environmental Policy Act and said that the BLM has failed to take a hard look at the impacts to fossils and sensitive wildlife species.

Molvar said the Adobe Town area is internationally known for its fossils of such mammals as sloths and rhinoceros that lived during the Eocene period.

He said the court halt was lifted after Veritas committed to a complete survey of fossil resources before the onset of the project. He said the measures committed to by Veritas "should resolve" the paleontological issues.

Molvar criticized the planned use of thumper trucks in a statement. He said the 32-ton vehicles would bring "unnecessary impacts" as they run four abreast across fragile landscapes in potential wilderness areas of Adobe Town.

"We're very disappointed that Veritas was unwilling to agree to a settlement that would have permitted the project to move forward with shot-hole methods (only), which would have yielded the same seismic data with much less impacts on wilderness qualities," Molvar said.

Foertsch said there will be a number of shot-holes in addition to the vibroseis trucks employed during the project.

"The BLM feels shot-holes and vibroseis trucks are about equal in the disturbance caused out there, which isn't long-term and it's not significant," he said. "They're both very low-impact methods of exploration compared to bulldozing roads and drilling dry holes."

Foertsch said depending on the wildlife exceptions, Global could possibly start the project in late June and begin recording activities in August. He said the project is expected to take from 60 to 75 days to complete.

Southwest Wyoming bureau reporter Jeff Gearino can be reached at 307-875-5359 or at gearino@tribcsp.com.