Relocation of a Research Reactor

The research reactor RA-8 is placed in Pilcaniyeu Technological Centre (PTC) in the province of Rio Negro, approximately 70 km east from San Carlos de Bariloche city. The first time the reactor went critical was in June 1997 and it is out of operation since March 1999. Due to the intention to relocate the reactor in Bariloche Atomic Centre (BAC) a study has been done in order to assess the technical and economical feasibility. The scope of this study covers the disassembly and transport from PTC to BAC. Relocation of the reactor will reduce costs, time and difficulties in the transport of personnel (operators, researcher, and students) to Pilcaniyeu allowing the performance of nuclear research as well as academic application. The RA-8 is basically a critical facility of enriched uranium with light water as moderator. It is a pool type reactor with low thermal power, maximum 100 W and nominal 10 W. The principal assembly and the associated systems are placed in the reactor hall: consisting of a core, tanks, block, nuclear and conventional instrumentation, moderator system and the neutron source system. Also there is a control room with computers for monitoring together with the safety and control systems. The core is inside two stainless steel concentric tanks communicated with each other that contain water during the operation. The technical feasibility consists in: radiological characterization of the facility, visual inspection of the systems, structures and components, dismantling engineering, mass estimation for disassembly, packing, transport and storage. Economical feasibility has been done in order to evaluate time and costs necessaries for the disassembly and transport from Pilcaniyeu to Bariloche. Regulatory aspects that must be fulfilled were considered in this study. Nothing detectable was found in water samples from pipes of the pumps' well. The systems, structures and components of the RA-8 present in general a good condition of preservation that would allow and justify its operation in another site. The inspected components presented no external degradation and those that were assayed worked correctly. Absence of contamination and activation facilitates to a great extent the disassembly of the reactor. The total mass was calculated in approximately 34 t that could be transported in 5 trips from PTC to the BAC. A minimum period of 9 months was estimated for the accomplishment of the project. Around a million U.S. dollar was the total cost evaluated for the disassembly and transports the RA-8 from PTC to BAC. (author)