According to the Bowling Green Daily News, plans to widen three highways in Mammoth Cave National Park must be approved by 30 regulators. The planning process takes four to five years. The projects will reconstruct park routes 10 and 15 and widen park route 110 to the Maple Springs Research Center.

More information: National Park Service: Draft Environment Assessment -- Reconstruct Routes 10, 15, and 110 , Daily News: Roads go through miles of red tape (June 29, 2002)