BISMARCK, N.D. (AP) – The Turtle Mountain Band of Chippewa has banned a contentious oil and gas recovery technique and wants to stop a federal auction that would open drilling on the north-central North Dakota reservation.

The Bureau of Indian Affairs’ Dec. 14 lease sale for 45,000 acres in Rolette County is outside North Dakota’s existing oil patch. State records show no oil has ever been produced in the county, but some tribal members believe advanced horizontal drilling techniques and hydraulic fracturing could spur development on Indian land and threaten water sources.

Eight council members representing the 30,000-member tribe unanimously passed a resolution last week that would forbid hydraulic fracturing on tribal land, which incorporates much of the county. The council later amended the resolution asking that the BIA halt its planned lease auction.

The BIA continued to advertise the lease sale on Friday.

“We have not received any official notice from the tribe regarding this matter,” agency spokeswoman Nedra Darling said in an email.

Hydraulic fracturing, or fracking, is a process that uses pressurized water, chemicals and grit to break open oil and gas bearing rock up to two miles underground. The technique is credited with allowing the development of the rich Bakken shale and Three Forks formations in western North Dakota. In other states, it’s been blamed for endangering water quality.

More than 500 tribal members have joined a group “No Fracking Way Turtle Mountain” to ban oil development on the reservation, said Cedar Gillette, a spokeswoman for the group.

“We believe fracking comes at too much of an environmental cost,” she said.

North Dakota has never had a case of hydraulic fracturing damaging water supplies, said Dave Glatt, the director of the state Health Department’s environmental health section.

More than half of the reservation’s 6,000 residents live in poverty, said Christa Monette, a tribal member. Oil development could bring in much-needed jobs to the reservation but at a cost, she said.

“It’s not that we don’t want economic development because we do – we just don’t want our environment harmed,” she said. “I’m not a tree-hugger. I just live here. This is my home.”

State geologist Ed Murphy said the rich Bakken and Three Forks extend into Rolette County, but contain only a fraction of the oil-bearing rock there that the formations hold in the western part of North Dakota.

“Rolette County is 60 miles east of where we think the Bakken and Three Forks is capable of generating oil,” Murphy said.

The closest producing oil wells to the county are 17 miles to the north in Canada and 30 miles to the west in neighboring Bottineau County, Murphy said. Those wells are aimed at a shallower formations and likely use traditional vertical drilling technology that does not require hydraulic fracturing, he said.

Stephan Nordeng, a Department of Mineral Resources geologist, said oil companies drilled test wells in Rolette County years ago with no success.

“They came up with quite a number of dry holes,” he said.

“There’s nothing out there right now,” Nordeng said of the prospect of oil in Rolette County. “But there is always somebody willing to gamble a little bit, because that’s what they would be doing.”

Ron Ness, president of the North Dakota Petroleum Council, said the tribe’s fears over hydraulic fracturing are unfounded. Ness, whose group represents more than 200 companies working in North Dakota’s oil patch, said he doubted if the BIA’s federal lease sale would have garnered much interest anyway. The tribe’s ban on hydraulic fracturing “puts them off-limits,” he said.

About 100 miles southwest of the Turtle Mountain Reservation is the Fort Berthold Indian Reservation in west-central North Dakota, home to the Mandan, Hidatsa and Arikara tribes, known as the Three Affiliated Tribes.

The tribes’ chairman, Tex Hall, said oil has brought promise but also problems to the reservation, which is home to half of the tribes’ 12,000 members.

A tax agreement between the state and the tribes that began in July 2008 has generated $66 million in oil tax revenue for the state and $31 million for the tribes, state Tax Department records show. The tribes also have collected more than $182 million in lease payments from oil companies for rights to drill on tribal land.

Unemployment has dropped from 50 percent on the reservation to about 25 percent with plentiful jobs in the oil patch and support industries, Hall said. At the same time, the influx of cash has spurred more crime, traffic, alcoholism and drug use, he said.

Carol Davis, a Turtle Mountain tribal elder, said she was proud of her tribe for banning hydraulic fracturing on the reservation.

“The tribe saw the potential for disaster and is really taking a bold stand,” she said.

Davis said she has relatives on the Fort Berthold reservation who have reaped financial benefits from oil development there.

“I’m basically telling my relatives to put that money in the bank, because they will be buying water from us,” she said.