Table Talk Robert H. McMahon, assistant secretary of defense for sustainment, presides over the first meeting of the PFAS task force in Washington, Aug. 9, 2019. SHARE IMAGE: Download Image: Full Size (0.87 MB) Tags: pfas Photo By: Air Force Staff Sgt. Andrew L. Carroll, DOD VIRIN: 190809-D-UO644-0012Y.JPG Photo Gallery