ELLSWORTH AIR FORCE BASE, S.D. -- (Right to left) Senior Airman Hugh Blacketor, 28th Civil Engineer Squadron heating, ventilation and air-conditioning journeyman, simulates decontaminating Airman 1st Class Michael Mays, 28 CES structural apprentice, during a phase II operational readiness exercise, Aug. 24. The exercise tests Airmen and their abilities to operate in a simulated deployed environment. (U.S. Air Force photo/Airman 1st Class Anthony Sanchelli)