After planning to reopen one lane of traffic on U.S. Highway 24 on Tuesday, the Colorado Dept. of Transportation reversed that decision and closed the highway for an indefinite period. The sink hole at mile marker 165, first estimated at 45 feet deep, was determined to be a collapsed railroad tunnel and was some 100 feet deep. CDOT has not determined how to make repairs or how long repairs will take. Updates at cotrip.org