EDF clears a contract hurdle before dismantling the first UNGG reactor
Serguey Asael Shinder2 min readEDF's subsidiary Cyclife reports that the Chinon A nuclear plant dismantling project has passed a milestone: the contractual strategy for taking apart the heat exchangers of Chinon A2 has been validated. The step followed more than three and a half years of joint study by Cyclife Engineering and EDF's Deconstruction and Waste Projects Department (DP2D), and it opens the first operational phase of dismantling what is described as the world's first UNGG reactor.
The context is a fleet, not a single unit. Six gas-cooled reactors of the Uranium Naturel Graphite Gaz design — at Bugey, Chinon and St Laurent-des-Eaux — are being decommissioned by EDF. They entered service between 1963 and 1972, and with the exception of Chinon A1, which shut in 1973, all ran for more than twenty years. Chinon A2 is the lead site for EDF's immediate-dismantling strategy for the whole fleet.
The first operation, subject to the dismantling decree coming into force, is to take apart in series the equipment in Chinon A2's four heat exchanger rooms. Those exchangers carried heat from carbon dioxide warmed in the reactor core to the water of the secondary circuit, where it became steam.
What it means
A validated contract is not a cut piece of steel, and the distinction is the whole story of UNGG. What has been achieved here is agreement on how the work will be procured and run. The regulatory instrument that authorises the work is still outstanding, and the announcement says so.
Three and a half years of study for the contracting strategy of one subsystem tells you the scale of the problem. Graphite-moderated, gas-cooled reactors were built before anyone had dismantled one, and there is no reference project to copy. France's immediate-dismantling choice for this fleet means the engineering, the waste routes and the contracts all have to be invented in the right order, and heat exchangers are the accessible end of that.
Watch the decree, not the press releases. For any reader tracking decommissioning schedules, the checkable date for Chinon A2 is when the dismantling decree enters into force. Everything announced so far is preparation for that moment.
⚠ This is an operator announcement relayed by a trade publication; the figures and the milestone are Cyclife's own account of its own project.
Source: https://www.world-nuclear-news.org/articles/france-prepares-to-start-dismantling-first-ungg-reactor