A draft of a government report says moving air and space surveillance missions from Cheyenne Mountain to Peterson Air Force Base could cost more than 50 million dollars.
The Government Accountability Office draft report says no estimates were available on costs for fortifying the new location.
A draft of the report was obtained by The Gazette newspaper.
Admiral Timothy Keating wanted to move North American Aerospace Defense Command and Northern Command from inside the mountain "to improve operational efficiencies."
The GAO says no cost-benefit analysis was conducted for moving NORAD and NorthCom.
The full report is due in May.