NEDERLAND - Eldora Mountain Resort kicked off its 50th anniversary season today by touting its new, smoke-free environment.

Smoking is banned in lift lines, on the lifts and within 15 feet of decks and buildings around the Nederland ski area, resort officials said. The ski area has a 20-inch base of machine-made snow.

Eldora is in the middle of  a 72-acre expansion-plan request started in March 2011. The resort has plans for new, heavier six-person lifts and an expanded ski area boundary. Some neighbors and environmental groups have raised concerns about the impacts on water quality and wildlife.

Vail Mountain, managed by Vail Resorts Inc. in Broomfield (NYSE: MTN), also opened today for its 50th anniversary. The si resort plans to dedicate a new gondola that has cabins with heated seats and Wi-Fi access later this month.

Vail Resorts mountains Keystone and Breckenridge also opened recently. The company features a tobacco-free workplace.