shipper of TRU waste to the WIPP. http://www.epa.gov/region8/superfund/co/rkyflatsindustrial/ The radioactivity of all nuclear waste diminishes with time. All radioisotopes contained in the waste have a half-life - the time it takes for any radionuclide to lose half of its radioactivity and eventually all radioactive waste decays into non-radioactive elements. Certain radioactive