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A group of Army Reserve Soldiers from the 327th Chemical Company, 92nd Chemical Battalion, 415th Chemical Brigade, 76th Operational Response Command enter a tunnel to conduct reconnaissance of a suspected chemical weapons cache during a training exercise at Dugway Proving Ground, Utah, June 20. More than 500 Army Reserve Soldiers from around the country are conducting a variety of specialized training at the base, focused on honing Soldiers chemical, biological, radiological and nuclear (CBRN) skill sets and obtaining unit validation as part of a three-week annual exercise known as Operation Desert Dragon. The exercise is designed to be the premiere CBRN validation event for Army Reserve units, and serve as the culminating training event for premobilization and top tier priority units. (Official U.S. Army Reserve photo by Sgt. 1st Class Brent C. Powell)