SALT LAKE CITY — Utah regulators set lax pollution standards for a strip mine near a national park, an expert witness testified Friday.

The Sierra Club and three other environmental groups are challenging a permit for the coal mine, saying the operation would pollute waterways and kick up dust 10 miles from Bryce Canyon National Park, which is known for its views, pristine air and sparkling night skies.

Bryce Canyon's superintendent also has objected.

Opponents contend Utah set a low threshold for sediment that would run off the strip mine into mountain lakes, streams and the wild and scenic Virgin River.

"There's a lot of water that runs onto the mine site," said Charles H. Norris, chief executive of the Denver consulting firm Geo-Hydro Inc. He said Utah's standards weren't tough enough to prevent muddying of waterways that already carry a high natural sediment load.

Norris testified before a citizens board for the Utah Division of Oil, Gas and Mining, the agency that approved the state's first coal strip mine, about 200 miles south of Salt Lake City.

The hearings were to resume Saturday.

The director of Utah's mining agency defended its decision to approve the strip mine.

"There's a difference in technical opinion," said John Baza during a break in the hearing. He said opponents "want us to step farther" to set stricter standards for tolerating salts and dissolved solids in mining discharge water.

Regulators don't have to do that, and they met all of Utah's legal requirements when they gave approval in October to Alton Coal Development LLC to strip 440 acres of private lands near the isolated Kane County town of Alton, he said.

The company is seeking federal approval to expand the strip mine onto thousands of acres of surrounding public lands, where the shallow coal seam continues. It has not revealed a buyer for the coal, but Utah has several coal-fired power plants.

Residents of nearby Panguitch are upset that the operation would dispatch coal trucks as often as 300 times a day, six days a week, through their town.

Much of Friday's hearing was taken up by Walton D. Morris, who grilled state regulators on their standards for tolerating dissolved solids and salts in mining discharge water.

Morris was a federal Office of Surface Mining attorney who has gained a national reputation for fighting coal mining. He tried to stop a reporter from asking Norris — his expert witness — to sum up his highly technical testimony during a break in the proceedings.

Norris spoke anyway, saying Utah's permit standards were ineffective in stopping water pollution from the strip mine. He said runoff from the mine would exceed a maximum allowed sediment load in area lakes, streams and the Virgin River.

"They're opening a dangerous door, the way the permit is written," he said.

Alton Coal Development LLC is a group of investors who have yet to obtain their permit, which is contingent on the company securing a multimillion-dollar reclamation bond.

James J. Wayland of Naples, Fla., a 50 percent owner of Alton, declined comment when reached Friday by The Associated Press.

The investors got fast-track approval after complaining in a meeting with Utah Gov. Gary Herbert that regulators were taking too long to make their decision. Alton opened its application for a permit in 2005.

A company representative sat down with Herbert on Sept. 17, the same day the governor's campaign was depositing a $10,000 contribution from the coal company.

Environmental activists and Panguitch business owners assert the donation influenced the Herbert administration's decision, but the governor's office has said he never ordered regulators to give their approval and wasn't aware of the donation.

A 33-page memo from the Utah Division of Oil, Gas and Mining said the result of the coal company's September meeting with the Republican governor was to fast-track a decision by regulators.

Priscilla Burton, a chief environmental scientist for the agency who wrote the memo, noted regulators had a full year left to make a decision but agreed to wrap things up Oct. 15. Approval came four days later.

Douglas E. Johnson, the chairman of the Utah Board of Oil, Gas and Mining, said the board would not make an immediate ruling in the case, but he declined to say how long that would take. The next step in the contest is expected to be at the Utah Court of Appeals, further delaying the project.

The company's permit is being challenged by the Utah Chapter of the Sierra Club, the Southern Utah Wilderness Alliance, the Natural Resources Defense Council and the National Parks Conservation Association.