Estimation of fission product activity in hull drum in spent fuel reprocessing plant

In fuel reprocessing plants during head end treatment, cladding material of spent fuel left over after dissolution in chopp-leach process is alpha bearing high active solid waste which is disposed in tile holes. It is necessary to estimate fission product activity in the drum containing hull. The paper describes different methods of hull monitoring in short and describes a simple method which is based on direct dose measurement and correlating dose with fission product activity based on MCNP model used along with the β:r activity ratio from laboratory analysis and isotopic composition of gamma emitters. (author)