Three groups concerned about the impacts of increased drilling for natural gas near a fragile outdoor collection of ancient rock art filed a lawsuit Wednesday in U.S. District Court, asking a judge to consider whether the Bureau of Land Management is following the law in approving each new well.

"It's an issue of the BLM approving wells one by one, essentially through what's a loophole in federal law," said Stephen Bloch, attorney for the Southern Utah Wilderness Alliance.

At the center of the suit is Bill Barrett Corp., which has received numerous approvals for new wells near Nine Mile Canyon, valued for its collection of cultural resources.

"It's essentially Barrett is impatient and the BLM is caving in to those pressures by approving these wells," Bloch said over the phone. He said the BLM is taking an "act first, think later" approach.

The company wants to drill more than 800 additional natural gas wells as part of its West Tavaputs project, which critics say will also industrialize an area valued for its wilderness.

"It's not about stopping, it's about clarification of the law and application of the law," said Pam Miller of the Nine Mile Canyon Coalition. Miller stressed she is not against drilling for natural gas.

Barrett's Duane Zavadil said in an interview Thursday his company will defend itself vigorously and that his company is not going to disrupt cultural artifacts in the canyon.

"The mere act of driving by cultural artifacts is not going to disturb them," said Zavadil, vice president over government and regulatory affairs.

BLM officials on Thursday declined to answer questions about the pending litigation.

However, reacting to Bloch's harsh words Thursday for the BLM, spokeswoman Mary Wilson did say, "We act in accordance with our statutory obligations and authorities."

Miller wants the BLM to consider the cumulative effects of approving wells on an individual basis rather than part of a larger picture. She said the increased truck traffic and activity in the Nine Mile area has led to more dust in the air and a negative impact on air quality, more vibrations that could impact rock art in the area and more risk to tourists who visit the canyon.

Watchdogs say efforts so far to suppress the dust have either fallen short or are actually threatening some roadside petroglyphs in Nine Mile Canyon.

Zavadil said once their Tavaputs project is approved that resulting improvements to the road and ongoing suppression efforts will make roads through Nine Mile Canyon less dusty than today.