The second category of waste for which a repository now exists in France is very low-level waste (VLLW).
In August 2002, ANDRA opened a VLLW waste repository named CIRES (Centre Industiel de Regroupement, d'Entreposage et de Stockage). This disposal facility is located in Morvilliers, a straight-line distance of 2 km from the Aube repository (CSA), which handles low- and intermediate-level waste.
The new facility is designed to accommodate 650,000 cubic metres of waste. The first waste was delivered on 1 October 2003. In 2011, the waste inventory by volume stood at 360,000 m3, of which 203,000 m3 had already been disposed of at the Morvilliers repository. More than 30,000 cubic metres are disposed of there each year, and this figure is rising.
The principal sources of VLLW waste include nuclear installations, a few industries that use radioactive mineral ores, restoration work at previously contaminated sites, etc. Thanks to the CIRES facility in Morvilliers, some of the waste generated by dismantling operations can now also be disposed of at a special-purpose repository in France.
ANDRA video about CIRES, the VLLW waste repository in Morvilliers
Approximately 30% of waste is compacted – to reduce its volume – or solidified, in the case of sludge, which is chemically stabilised and then mixed with a hydraulic binder.
After being conditioned, the waste – in the form of metal containers, big bags of rubble, metal drums and solid metal components – is placed into disposal cells excavated into the clay. An opening roof is erected over disposal cells while they are being filled, to protect against rain. The clay soil's retaining properties ensure that any residual long-lived radioactive atoms will be durably contained. Water quality is monitored while the site is filled. This monitoring will continue during the subsequent monitoring period, pending the return to natural background radioactivity levels.
The VLLW waste repository in Morvilliers is filling up more rapidly than originally planned. Current predictions point to a volume of 762,000 m3 by 2020 and 1,300,000 m3 by 2030. This increase is partially attributable to the dismantling of decommissioned basic nuclear installations, such as the Siloe and Melusine research reactors in Grenoble.
Several options for increasing waste disposal capacity are possible: expanding capacity at the facilities in Morvilliers; creating a new VLLW repository; and creating in situ repositories for certain waste at dismantled facilities. Certain VLLW waste could also be recycled or managed differently, for example, by compacting crushed rubble in VLLW disposal cells.
ANDRA video To protect the planned disposal cells at the CIRES repository, ANDRA has developed the Prémorail opening roof, featuring a metal structure mounted on rails.