Аннотация:The paper focuses on the 14C, 36 C1, and 60Co radionuclide distribution in graphite stacks and blocks, whichplay a crucial role in the decommission of uranium-graphite reactors. The shutdown uranium-graphite reactorADE-5 provides an access to the graphite stack for the removal of graphite blocks. New interpretations aresuggested for the radionuclide distribution in bulk graphite stacks based on testing results of graphite blocksremoved from the uranium-graphite reactor ADE-5 in 2018.