SANTA CLARITA, Calif.--Petty Officer 1st Class Jonathan Davis and Petty Officer 2nd Class Cody Tedeschi of the Pacific Strike Team work to stop a leak in a chlorine cylinder at an emergency response drill at the Del Valle Regional Training Facility in Santa Clarita, Calif., Feb. 2, 2012. Teams with the National Strike Force annually conduct exercises to safely train new members in the challenging conditions often encountered at actual responses. U.S. Coast Guard photo by Chief Warrant Officer Shane Barrington.