This bill requires the Department of Defense to take action against PFAS contamination, which are harmful "forever chemicals" used in products like firefighting foam that accumulate in soil and water near military installations. Within two years of the bill becoming law, the Secretary of Defense must start cleanup efforts at a minimum of 100 military sites where PFAS remediation has fallen behind schedule, and must complete any ongoing cleanup work already underway. The bill identifies roughly 727 Defense Department installations that have been assessed for PFAS contamination, and targets those where cleanup timelines have slipped since late 2024. The Secretary must also brief Congress within 30 days on the status of PFAS cleanup efforts across all affected military facilities. The bill allows the Defense Department to clean up fewer than 100 sites only if it cannot find enough sites that meet specific contamination criteria, and requires the department to report to Congress if it uses this exception.