CONTRIBUTION OF SPENT FUEL SHIPPING CASK RESIDUAL CONTAMINATION TO THE TRANSPORTATION SOURCE TERM

The US code of Federal Regulations for packaging and transportation of radioactive material, 10 CFR Part 71, requires that all shipping packages used to transport irradiated reactor fuel in the US be designed, constructed, and prepared for shipment so that: "(1) under the tests specified in Section 71.71 (Normal Conditions of Transport), there be no loss or dispersal of radioactive contents as demonstrated to a sensitivity of 10/sup /minus/6/ A sub 2 per hour; and (2) under the tests specified in Section 71.73 (Hypothetical Accident Conditions), there be no escape of krypton-85 exceeding 10,000 Ci in one week and no escape of other radioactive material exceeding a total amount of A sub 2 in one week." The quantity A sub 2 is derived from dosimetric models and varies for each nuclide in accordance with its radiotoxicity.