REACTOR PRESSURE VESSEL REMOVAL AT A BOILING WATER REACTOR WITH SPENT FUEL IN THE ADJACENT FUEL POOL

A Reactor Pressure Vessel Removal Feasibility Study was prepared for use in the decommissioning planning for the Oyster Creek Nuclear Generating Station. The primary consideration of this study was to determine if the RPV could be safely removed from a boiling water reactor with spent fuel in the adjacent spent fuel storage pool. The scope of the study included: ∞ Developing alternates for prompt removal of the Reactor Pressure Vessel (RPV) intact (with or without internals), in sections (large pieces), and in segments (small pieces). ∞ Identifying applicable licensing requirements, heavy rigging equipment, cutting methods and tooling, building modifications, and engineering safety features for protection of the spent fuel pool and associated equipment. ∞ Providing schedules, comparative cost estimates, personnel radiation exposure estimates, and an occupational safety assessment for the feasible alternates. The study determined that there were several feasible methods of safely removing the RPV with spent fuel in the adjacent spent fuel storage pool. The best method for removal was judged to be intact removal by lowering the RPV along a path through the bottom of the Drywell rather than lifting the RPV above the Drywell. This method was selected because its dose, cost and schedule duration provide the best combination of these parameters while eliminating the risk to the spent fuel pool by employing a single failure proof rigging system. Further, this alternate retains the option of leaving the lower internals inside the RPV, which substantially reduces the dose, cost and schedule duration relative to other methods requiring removal of the internals. Of the intact alternates, the lower Drywell method also provides the best opportunity for regulatory acceptance. This paper provides a summary of the various considerations, inputs, characteristics, factors, and results from the study related to removing the RPV from the Reactor Building. This paper also provides the final conclusions of the study - that safe removal of the RPV can be accomplished from a BWR with spent fuel in the adjacent fuel pool in compliance with all NRC regulatory and license requirements.