U.S. Air Force Staff Sgt. Michael LeMõn, 633rd Communication Squadron cable and antenna supervisor, and Airman 1st Class Austin Zudak, 633rd CS cable and antenna apprentice, unpack tubes to pump out a water-filled manhole at Joint Base Langley-Eustis, Va., Nov. 15, 2016. After pumping out the water, the technicians test the amount of gas in the manhole to ensure the safety of the Airmen entering the hole. Gas forms under the water due to its greater density. (U.S. Air Force photo by Kaylee Dubois)