Two Utah ski areas received a top 10 grade from a group that graded the environmental friendliness of more than 80 ski areas in the West.

The Ski Area Citizens' Coalition says that regionwide, 53 of the 83 resorts it reviewed this year boosted their scores, but seven received failing grades.

Sundance Resort and Park City Mountain Resort ranked No. 3 and 4, respectively, among the top 10 listed by the coalition. Aspen and Buttermilk resorts in Colorado ranked No. 1 and 2, respectively.

In its report, out of 100 possible percentage points, the coalition gave Sundance 82.2 percent for, among other things:

• Beginning a resortwide energy efficiency retrofit.

• Purchasing almost 200,000 kilowatt hours of renewable wind energy credits each month.

• Offering discounts to guests who car-pool.

As for Park City resort and its 79.1 percent grade, the coalition cited it for:

• Installing lighting timers and motion sensors in its energy efficiency retrofit.

• Purchasing renewable energy credits.

• Supporting "green" policies.

Other Utah resorts included in the report and their percentages were: Snowbird, 73.3 percent; Alta, 71.9 percent; Deer Valley, 67 percent; Brighton, 60.3 percent; Snowbasin, 59.7 percent; The Canyons, 59 percent; Solitude, 57.7 percent; and Brian Head, 45.8 percent.

The resort with the lowest score was Colorado's Copper Mountain, which ranked at 31.9 points for an "F," the coalition said.

Copper Mountain's score was almost entirely due to an expansion of terrain and real estate development, coalition research director Hunter Sykes said. Aspen was credited for trying to minimize impacts of development, Sykes said.

"The scorecard is weighted heavily against ski area and village development and doesn't credit resorts' sustainability initiatives or community involvement," Copper Mountain spokeswoman Lauren Pelletreau said.

She said Copper's "green" efforts include buying renewable energy credits, matching employee donations to an environmental fund, and installing a 4.2-kilowatt solar system on a transportation building. A new car-pooling initiative on certain Saturdays this season offers visitors who arrive in vehicles with at least four people a chance to win season ski passes for 2009-10.

Sykes insisted that new development doesn't automatically mean a low grade, although the financially crunched Tamarack Resort in Idaho received an "F" in its first year on the scorecard this year, largely because of its newness. Arizona Snowbowl — with plans to add snowmaking, lifts and trails — received an "F."

He said points awarded for using renewable energy and energy-efficient technologies, for example, can offset deductions for development. "We do give due credit to what resorts are doing," Sykes said.