Congress is voting on whether to cancel an EPA decision that had approved South Dakota's plan for reducing air pollution that clouds visibility in national parks and wilderness areas (this is part of a federal program requiring states to cut haze-causing pollution, mostly from industrial sources, so that scenic views stay clear). If this resolution passes, South Dakota's EPA-approved haze-reduction plan would be voided, meaning the state's specific approach to controlling this pollution would no longer be in effect and the state would likely need to submit a different plan. This mainly affects industries in South Dakota that emit haze-causing pollution, as well as anyone who visits or lives near the state's national parks and wilderness areas and cares about air clarity there.