Skiers, in general, tend to be more environmentally aware than the rest of the population. Ski resorts are another matter entirely. Different resorts deal with the natural resources around them differently and some are more green than others. If you want to ski at a responsible resort you should check out Ski Area Citizens' Coalition (SACC) website.
SACC ranks the top ten as well as the ten worst environmentally-friendly ski resorts. You can select your area of the country and find out what resorts near you scored well on the environmental report card. The resorts were graded on how they impact roadless areas and if they purchase clean energy, participate in making new snow, are involved with logging old growth forest, among other criteria. Being green on a large scale is more than just having a recycling program.
I was surprised that Kirkwood, by Lake Tahoe in California, was given an F. It seems their land preservation policies just plain stink. On the other hand, family-friendly Alpine Meadows, also in the Tahoe area, is environmentally friendly.
Bring the color green to your Winter sports season that is usually covered with white. Ski Green!