Plans to demolish outdated Brigham Young University dormitories are causing a dust-up.

The university, which wants to implode two of the Deseret Towers residence buildings, heads to the state Air Quality Board today to request a variance from regulations that limit dust.

Its request pits the Provo-based university against air-quality staff who say the implosion would send a thick cloud of powdered rubble into the air - a cloud dense enough to exceed state standards. The request also puts the Air Quality Board in the uneasy spot of being asked to grant an exception to the university that it generally denies to businesses and other institutions.

BYU spokeswoman Carri Jenkins said the university wants to begin demolition as soon as students go on Christmas break Dec. 22, and clean up the site by their return on Jan. 8. Using specially mixed explosives to collapse a building in on itself costs about the same as using a wrecking ball, but it would mean less disruption, she said.

"It was determined this would be the most efficient way to demolish these buildings," Jenkins said.

Both seven-floor buildings, casualties of the switch to apartment-style housing, have been empty all fall. Each holds 264 students.

The Division of Air Quality has discussed the plan with BYU at several meetings, said Robert W. Ford, manager of the state air division's hazardous air pollutants section. Staff analysis suggests implosion will mean too much dust at the site and off the university boundaries.

"From our perspective, we cannot support the variance based on the information that as been submitted so far," he said.

Meanwhile, an environmental group, the Wasatch Clean Air Coalition, has voiced concern that lead from old paint and asbestos from old insulation, flooring and ceiling tiles might drift into surrounding neighborhoods.