The State Line Generating Station is a hulking coal-fired power plant that sits just off Lake Michigan, along the Indiana-Illinois border. Even people who don’t know the structure’s name or its purpose may recall its most recognizable feature: the red and white building that towers close to the Chicago Skyway. It’s produced power and air pollution for decades, but no more. The plant was finally shuttered in April 2012. It's future use is uncertain at this time.