COLLBRAN, Colo. —Crews are searching the bottom edge of a massive mudslide in western Colorado for three men who went missing after checking on damage from an initial slide.The men haven’t been heard from since a half-mile wide piece of ridge, saturated by heavy rain, collapsed Sunday and sent mud sliding for 3 miles.Sheriff Stan Hilkey said the search has been hampered because only the lower third of the slide is stable. At the edges there, the mud is 20 to 30 feet deep. It’s believed to be several hundred feet deep in some places.Hilkey says everyone is praying for a miracle but said no signs of the men or their truck have been found.He has consulted with the sheriff who responded to March’s mudslide in Washington state for advice on how to handle the search.Authorities said no structures or major roads were affected by the large mudslide. It hit Sunday near the town of Collbran, about 40 miles east of Grand Junction and near the edge of Grand Mesa, one of the world’s largest flat topped mountains. Deputies estimate that the entire ridge had been moving for most of Sunday before someone called to report the slide at 6:15 p.m., describing it as sounding like a freight train.“This slide is unbelievably big,” said Mesa County Lt. Phil Stratton said.Authorities said the unidentified men were possibly caught in the slide but haven’t released any other details.Bill Clark, a cousin of one of the missing men, said the three went to check for problems in the area Sunday after a rancher reported that his irrigation ditch had stopped flowing. Clark visited the canyon where the slide struck and said it was filled with about 700 feet of mud. He said it struck with so much force that some also spilled over into the neighboring draw too.