The number of active and former U.S. military installations found to be contaminated with chemical compounds found in firefighting foam is expected to rise as a Defense Department task force investigates the scope of the problem, the group's chairman said Sept. 12. Assistant Secretary of Defense for Sustainment Bob McMahon told reporters during a media roundtable that he "expects to see growth [in the number of bases contaminated with per- and polyfluoroalkyl substances, known as PFAS] as we begin to get a better understanding and better characterization of where we are." Read more on Military.com.