Utah, Arches National Park
On March 7, a large rockfall occurred during a technical rock rescue training session being conducted in the Park. Seventeen people were attending the training. The rock, estimated to be between 30 and 40 feet long and weighing over one ton, fell nearly 300 feet from the top of a sandstone cliff. It struck a small protrusion near the beginning of its fall, causing a loud noise, then broke up on its way down. The noise alerted six people who were directly below, sitting down to take a lunch break. They scattered just before the rock hit the ground a few yards behind the lunch location and exploded. Two park employees were injured. Andrew Fitzgerald was knocked to the ground by flying debris and suffered a head injury and multiple lacerations; Lee Kaiser, who was not among the six, injured his leg slightly while trying to get away from the flying rock. Fitzgerald was treated for his injuries, secured to a litter, lowered over the side of a 100-foot cliff to a second team, then transported a quarter-mile cross country to a waiting ambulance. His injuries turned out to be relatively minor, and he was released from the hospital later that afternoon.
Rain had fallen off and on for several days prior to the training session. Examination of the release site at the top of the cliff revealed that a large sandstone flake had simply let go of the surrounding rock. The rain-weakened condition of the sandstone, an existing crack in the rock, and freeze-thaw conditions typical of late winter in the area are thought to have been the primary reasons for the natural release. The high-angle rock rescue training is a joint NPS and Grand County SAR session conducted annually before the visitor season begins. Those who were directly below the falling rock with Fitzgerald, and therefore had a “near death experience,” were Murray Shoemaker and Nathan Plants from Arches National Park, Dan Habig from Canyonlands National Park, and Bego Gerhart and Frank Mendonca of Grand County SAR. (Source: Jim Webster, Ranger, Arches National Park)
(Editor's Note: Engaging in “area security” helps to determine conditions that may have changed for many venues. In climbing, routes may change as a result of freeze/ thaw cycles—both for rock and ice. Knowing the history of the snow pack is critical for understanding potential avalanche conditions.)