In better mass transit news, Yellowstone National Park is in the early stages of launching a public-transportation plan designed to cut down on air and noise pollution. Harkening back to its past, the park has reacquired a small fleet of yellow tour buses that were phased out of service in the 1950s. The park plans to refurbish the buses and use them as shuttles between some of Yellowstone’s most popular destinations. Park officials envision a future of multiple mass-transit options to help reduce the traffic snarls caused by private vehicles. Environmentalists are giving the thumbs up to the plan. Jon Catton, a spokesperson for the Greater Yellowstone Coalition, said, “We’re adding several million people to our country’s population each year and we’re not making any more Yellowstones.”