7 Jun (NucNet): France’s nuclear operator EDF wants to change its decommissioning approach for the country’s six first-generation gas-cooled reactors from wet dismantling to dry dismantling. The company told nuclear safety authority ASN (Autorité de Sûreté Nucléaire) it will carry out the complete dismantling of one of the six reactors, at the St. Laurent, Chinon and Bugey nuclear station sites, before beginning the dismantling of the other five. This will allow it to benefit from the combined experience. EDF said the dismantling of all peripheral reactor equipment at the six units, which were all permanently shut down between 1973 and 1994, should be completed within 15 years. ASN had called for a review of EDF’s plans for the six units and will now examine the revised strategy. The six units are: St. Laurent A-1 (390 MW); St. Laurent A-2 (465 MW); Chinon A-1 (70 MW); Chinon A-2 (180 MW); Chinon A-3 (360 MW); and Bugey-1 (540 MW). The units are all UNGG (Uranium Naturel Graphite Gaz) plants, an obsolete reactor design developed by France. UNGG reactors were graphite moderated, cooled by carbon dioxide, and fuelled with natural uranium metal. The first generation of French nuclear power stations were UNGGs, as was Vandellos-1 in Spain, which was permanently shut down in 1990. There were also three similar UNGG reactors at the Marcoule nuclear site in southern France. They were owned and are being decommissioned by the French Alternative and Atomic Energy Commission (CEA).
