Protesters want Colorado to 'stop clowning around' on clean air

Colorado air-quality regulators face pressure regarding renewal of a pollution permit for Denver's biggest coal-fired power plant – just as new studies from ASU show nitrogen- oxide emissions are turning once-clear mountain lakes cloudy. Researchers have found that nitrogen oxide – wafting from power plants, vehicles and agriculture – increased fourfold over the past 20 years in lakes above timberline at Rocky Mountain National Park, changing lake biology and threatening the long-term survival of fish.