Thls report was prepared a s nn account of Government sponsored work. Nelther the Unlted States, nor the Commlsslon, nor any persoa acting o; behalf of the Commlaston:A. Makes any warrnnty o r representation, expressed or implled. wlth respect to the accuracy, completeness, o r usefulness of the Informnuon contained In tbls report, or (hat the use of any InformaUon, apparatus, method, or process dlsclosed In tbls report may mot Infringe privately o w e d rlghts; o r II. A6@uiea tiny llabllltles wltb respect to ihe use of, o r for damages resulung from the use of any information, apparatus, method, o r process dlsclosed In (hls report. I' % 1 As used In the above, "Person a c t h g on behalf of the C o m m l s s l o n~~ Includes any em-' . . 4 ' + 1 ployee o r contrnctor of the Commlssfon, or employee of such contractor, to the extent Ulat , 7,' such employee o r contractor of the Commlsalon. or employee of such contractor prepares. i f dlesemlnntes, o r provldes access to. nny lnformat~bn pursuant to his employment o r contract { 4 w~t h the Commission, or h~s employment with such cbntractor. -t . -ABSTRACT A pilot-plant-s'cale facility, the Contamination-Decontamination Experiment, was built and operated t o produce mixtures of high-level, short-cooled (6-t o ' 10-hr) fission products under conditions simulating' an unperturbed loss-ofcoolant reactor accident. The mixtures were created by melting irradiated, zirconium-clad UO fuel pins in steam. The fission products released from the SUMMARY The C ontamination-Decontamination Experiment (CDE) is a pilot -plant facility for producing and sampling mixtures of high-level, 6-to 10-hr cooled fission products under conditions simulating an unperturbed loss-of-coolant accident for a water-cooled reactor. The fission product mixtures -produced by induction melting of irradiated, zirconium-clad UO2 fuel pins -a r e transported by air-free steam to an 86433 stainless steel containment vessel in which the environmental conditions ,of a loss-of-coolant accident a r e simulated, Successful completion of five high-level runs and numerous trace-level and nonradioactive runs has demonstrated the safe operability of the CDE.Although the CDE is primarily a test facility to evaluate decontamination problems and to test samplers and analysis methods for the Loss-of-Fluid Test (LOFT), considerable information on fission product behavior was obtained during its operation.The behavior of fission products in the integrated-accident-sequence, highlevel CDE runs generally confirms the pattern expected from the results (I€ low-level, separate-effects experiments conducted elsewhere. The fractional releases of fission products decreased in the order: krypton and xenon, iodine, tellurium, cesium, molybdenum, ruthenium, barium, strontium, cerium, and zirconium -a s expected. Approximately 100% of the xenon and krypton, 50% of the iodine, 10% of the tellurium, cesium, and molybdenum, and less than 1% of the less volatile fission products present inthe fuel were released in the CDE runs, in wh...