The U.S. Park Service is now listing damage from a fire early Monday in the Timpanogos Cave National Monument information center at $1 million.

Officials from the Park Service's Rocky Mountain regional office in Denver arrived in American Fork on Tuesday to decide whether the center can be salvaged and rebuilt or should be replaced.It probably would take two years to rebuild or replace the visitors center. Despite the loss of the building, the Park Service plans to open the Timpanogos Cave trail and begin cave tours on May 4 as scheduled, said Mike Tranel, chief ranger at the monument.

The Park Service will set up a temporary ticket booth and information center at the base of the trail to serve visitors.

The fire, which started in an extension cord plugged into heating tape on the building's roof, consumed 90 percent of the building, Tranel said. The fire apparently smoldered for several hours, filling the building with smoke. A motion sensor alarm in the building went off at 2:47 a.m., apparently activated by the smoke.

Firefighters from Pleasant Grove and Alpine fought the blaze from 3:15 a.m. to 8:30 a.m., Tranel said. Pleasant Grove used 100,000 gallons of water fighting the fire, according to City Council member Lloyd Ash.

"The fire was hot enough in places to disfigure metal," Tranel said.

However, Park Service personnel were able to save 90 percent of the artifacts on display at the center, as well as historical photos, about half of their written records, half of the books for sale at the center and some audiovisual equipment.

The biggest loss in the blaze was the center's computer system, which contained "a lot of research data, management information and reservation data," Tranel said.

Many groups had already scheduled cave tours for the upcoming season.

"We're going to have to piece it together as best we can," he said. "We do have some written evidence of who scheduled. It's going to take a lot of work to put the thing back together."

The Park Service has re-established its telephone line at the cave (756-5238) but Tranel is asking that people wait until March before trying to schedule tours or verify reservations.

Last year, 130,000 people stopped in at the cave's information center; 85,000 to 90,000 people hiked to Timpanogos Cave.