This bill clarifies the Department of Energy's (DOE) authority to dispose of specific foreign-origin fissile or radiological materials at the Waste Isolation Pilot Plant (WIPP), addressing a current limitation where U.S.-origin americium-241 (Am-241) is accepted but Russian-origin Am-241 is not, despite their identical properties. The legislation aims to resolve this discrepancy by expanding the types of materials WIPP can accept to enhance nuclear nonproliferation efforts. The bill amends existing law to include the collection, storage, and safe disposal of certain proliferation-attractive fissile or radiological materials as "atomic energy defense activities." These newly eligible materials must contain foreign-origin transuranic elements and be similar to other proliferation-attractive materials already covered, but for their foreign origin. This change facilitates the disposal of substances like Russian-origin Am-241, which pose a risk of being used in radiological dispersal devices, and is expected to have a negligible impact on WIPP operations. By codifying a clear disposition pathway, the National Nuclear Security Administration (NNSA) can accelerate the removal of these dangerous materials from international facilities. This action is crucial for reducing the availability of substances that could be used in a "dirty bomb," thereby strengthening global security.