Feasibility studies of one-piece removal method for large reactor. Methods of removal, transportation and disposal of reactor pressure vessel with reactor internals

This report describes one-piece reactor removal feasibility study of the large BWR or PWR type reactor which has 40 years operation, followed by 3 or 10 years cooling time before actual removal/transport work with or without 40 years storage in the site. The scope of the study for the future decommissioning planning includes: Developing alternates for prompt or deferred removal of Reactor Pressure Vessel (RPV) intact with reactor internals, biological shield and RPV intact with reactor internals etc. Estimation of schedule duration, workload and personal radiation exposure for several one-piece reactor removal methods. Transport methods from reactor site to repository by transporter and barge. Tunnel disposal concepts for RPV package at 50 m deep underground access route by inclined shaft or vertical shaft. Cost estimation for removal methods of RPV intact with reactor internals, transportation and tunnel disposal for RPV package. Those alternate methods are highly effective at reducting waste disposal volume, cost and radiation exposure as compared to conventional methods of both RPV and reactor internals segmentation methods. (author)