 On the Colorado side of the monument, at one point, the raft became pinned on a rock, according to officials, and Harp went missing. Now, it's not clear how Harp had fallen off of the raft, but members of the group believe that he became pinned under the boat. Now, when the dislodged boat was pulled out of the water, they told monument officials that Harp became dislodged and drifted down the river. They said he somehow lost his life jacket.