In 2010, Amtrak (the current owners of the Chicago Union Station Company) announced plans to air-condition the Great Hall for the first time since the 1960s. That year a "Chicago Tribune" investigation revealed high levels of diesel soot on the underground platforms of Union Station. Metra established an "Emissions Task Force" to study this problem and recommend solutions to improve air quality in the underground areas. In 2011, its lighting system was replaced with more energy-efficient light bulbs and motion sensors, reducing the station's annual carbon emissions by 4 million tons. Custom steel lighting covers were added to top these safety/light towers, helping them blend in with the overall neoclassical style of the station.