By Leslie Jorgensen and Dena Zocher The purity of untracked snow. The silence and majesty of the backcountry in winter. The joy and adventure of experiencing nature on its own terms. These things and more are luring growing numbers of skiers in Colorado to venture outside the groomed, mechanized boundaries of ski areas. But behind the sheer exhilaration, underneath all that unequalled beauty, lies a serious, life-threatening risk: Avalanche. For ski resorts, customer safety is essential, and these properties are carefully mitigated for avalanche risk. But in the backcountry, even the most experienced trekkers need to take the potential of ...