Study on NUREG-2215 Regulatory Condition for Reflooding of the Previously Dried High Burnup Fuel Is Not Allowable During Dry Storage

Abstract This paper studies the regulatory condition for reflooding of the previously dried high burnup fuel is not allowable in the NUREG-2215 review guidance issued by the NRC, to evaluate the regulatory applicability of this condition to the retrieval operations in Taiwan’s indoor dry storage facilities. The discussion content firstly explains the research background and purpose of this paper, and then introduces NUREG-2215. And refer to NUREG CR-7198, Revision 1, NUREG-2224 and other research reports, as well as NRC’s response to public comments, to discuss the regulatory basis for reflooding of the previously dried high burnup fuel is not allowable. And from the NUREG-2224 evaluation results, it is known that intact high burnup fuel can withstand at least one thermal cycle exceeding 65°C without affecting the safety analysis of transportation or storage based on design basis accidents. The latest NRC review operation has also eliminated the restriction of reflooding, but high burnup fuel stored for more than 20 years needs to undergo additional supplementary analysis according to the recommended method. Subsequently, the feasibility of applying this regulatory condition to Taiwan is evaluated based on items such as the regulatory situation, characteristics of spent nuclear fuel cladding, retrieval facilities, and retrieval operations.