Oct. 7, 2019 Expanded site investigation underway at 167th Airlift Wing Drilling began at the 167th Airlift Wing, Martinsburg, W.Va., as part of an Expanded Site Inspection the Air National Guard base and surrounding areas for perfluorooctane sulfanate (PFOS) and perfluorooctanoic acid (PFOA), together referred to as PFAS, Sept. 25.