(Bloomberg) -- A Utah conservation group asked a judge to invalidate the sale of 43 oil and gas leases on land jam-packed with some of the nation’s most significant archaeological resources.

Friends of Cedar Mesa is challenging lease sales covering approximately 51,400 acres of public lands in San Juan County, according to a federal lawsuit filed Feb. 6 against the U.S. Bureau of Land Management.

The area includes so many sites it would take an “army of archaeologists decades to map them,” the group says in its complaint, quoting one expert. Some 1,346 ancient sites have been recorded, and cliff dwellings and pueblos show 9,000 years of inhabitants. The region is also a burgeoning tourist destination, with the Bears Ears and Canyons of the Ancients national monuments sitting on its doorstep, the group says.

“We’re talking about an area of America that has more archaeology per square mile than anywhere else in America,” Josh Ewing, executive director of the group, said in an interview.

The group says the Bureau of Land Management acted arbitrarily and failed to adequately study the impact of the lease sale on cultural and environmental resources, in violation of federal statutes.

The bureau, an arm of the U.S. Interior Department, declined to comment on the lawsuit.

Cultural Significance

The land has cultural significance to a variety of Native American peoples, like the Hopi Tribe, Ewing said.

“Litigation is our absolute last resort,” he said. The Bureau of Land Management “wasn’t willing to work with us at all. They weren’t willing to reduce the sale even by one acre.”

According to the complaint, only a small portion of the land has been surveyed for archaeological resources. Under the Obama administration, the Bureau of Land Management routinely refused to put the acres up for a lease sale.

“Oil and gas leasing will have significant, irreparable impacts,” according to the complaint. “Ground clearing and grading can disturb buried archaeological materials and wildlife habitat. Industrial traffic and ground clearing can increase dust particulates that degrade fragile rock art panels.”

The complaint went on: “Construction of new access roads can increase site visibility and accessibility, leading to increased vandalism, looting, and accidental disturbance of historic resources. The sights and sounds of drill rigs, pump jacks, compressor facilities, and pipelines also detract from the natural setting.”

Last year’s lease sale was the first of three. Three companies bought most of the parcels, with an average price of about $28 per acre, said Sarah Stellberg, a lawyer for the Friends of Cedar Mesa. The companies aren’t named as defendants.

The case is Friends of Cedar Mesa v. U.S. Department of the Interior, 4:19-cv-00013, U.S. District Court, District of Utah (Central Division).

To contact the reporter on this story: Carlyann Edwards in Washington at cedwards136@bloomberg.net

To contact the editors responsible for this story: David Glovin at dglovin@bloomberg.net, David S. Joachim

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