Chairlifts at the Arizona Snowbowl near Flagstaff, Ariz., carry skiers uphill. The Navajo Nation has argued that snowmaking violates Navajos’ religious rights on a mountain they consider sacred and that using treated wastewater will make people sick. The Navajo Nation has turned to an human-rights commission that normally deals with death-penalty cases and international justice in its effort to block a sky resort from using treated wastewater to make artificial snow at the resort.