Plans to build a chairlift in the Aspen Mountain sidecountry terrain known as Pandora have been put on hold as the Aspen Skiing Co. sorts out a complex patchwork of mining claims in the area.

Clearing up the web of privately and publicly owned land behind the Sundeck on the backside of the ski area has delayed the SkiCo in submitting its scoping letter to the U.S. Forest Service that will seek permission to begin updating the Aspen Mountain Master Plan, said Rich Burkley, SkiCo’s vice president of mountain operations.

The master plan update also includes other capital projects, such as a new chairlift in the Back of Bell area that would make intermediate terrain at the top of Ajax more accessible.

“We are making sure that we have clean title to the land back there,” Burkley said of the Pandora area. “Ajax is a web of mining claims, private land and Forest Service land.

“What we didn’t anticipate is the complexity.”

The area in question is behind the Sundeck on Richmond Ridge, which is where the terminal of a new chairlift would go that would serve the currently out-of-bounds Pandora area. The steep slopes, popular with expert skiers, are mostly on U.S. Forest Service land and are accessible through a backcountry gate on the east side of the mountain, but ski patrol does not perform avalanche control work there.

The SkiCo was aiming to submit the scoping letter to the Forest Service in February or March, but because officials have discovered a patchwork of historic mining claims that aren’t patented, SkiCo’s legal team is trying to sort it out.

“We don’t want to build a lift on land we don’t own,” Burkley said.

As a result, plans are on an indefinite hold and “we certainly have lost a year,” Burkley said.

SkiCo sent the White River National Forest a letter informing the agency that no plans will be pursued this summer.

The scoping letter is for entitlements — permission from government agencies — to proceed with planning capital projects, which in this case could take a decade.

A Pandora chairlift was put in the 1997 Aspen Mountain Master Plan. That plan was approved by the Forest Service, and any update to it would require a review and subsequent approval.

The SkiCo held a community meeting last fall to lay out its updated plans, which are mostly geared toward making the expert-oriented ski area more accessible to intermediates by giving them more ways to stay on the gentler slopes near the top. However, advanced skiers would get the bonus of a new chairlift in the Pandora area.

As presented last fall, a new Pandora lift would add an additional 160 acres to the mountain, in an area that is currently considered the sidecountry, which refers to terrain that has backcountry characteristics but is accessible from the ski area. The Pandora lift also would add about 400 vertical feet of skiing below the current egress for Walsh’s and Pandora, and would end on Richmond Ridge behind the Sundeck. Altogether, the new fixed-grip triple chair would have a vertical rise of about 1,200 feet with a ride time of nine minutes. Three new trails would be cut, and an additional area to the east around what’s known as Powerline would be gladed.

The proposed terrain expansion in Pandora is within the existing permit area but currently outside of the operating boundary.

The crux of the plan on the front side of Aspen Mountain would see the removal of the Gentleman’s Ridge chair — also known as the Couch or Chair 7 — and the Bell Mountain chair. A new Back of Bell chair would be built that takes skiers from the top of Copper Bowl to the summit of Bell Mountain — a ride of about 570 vertical feet in just over four minutes.

Extending snowmaking to the top of the mountain also is part of the plan. Currently, snowmaking ends at the top of the Deer Park run, leaving the very top of the mountain without snowmaking ability.

All elements in the plan are subject to change before the SkiCo submits its scoping letter to the Forest Service, officials noted.

sack@aspendailynews.com [1]