Decommissioning waste

The IAEA estimates that reprocessing would convert this 30 to 50 tons of SNF into 15 m³ of vitrified HLW.35 This conservative estimate of course does not include the vast amounts of reprocessed uranium, plutonium, intermediate-level waste, and spent mixed oxide fuel (MOX) that require extensive additional intermediate storage periods.36 In Europe, reprocessing is still part of the waste management concept in some countries (France, the Netherlands, Russia), while most countries have suspended or stopped it for mainly economic reasons (Belgium, Bulgaria, Germany, Hungary, Sweden, Switzerland, and most recently the UK). The latest European country to show interest in reprocessing is Ukraine, which signed a contract for a feasibility study with France’s Orano (formerly Areva). The initiative is part of Ukraine’s effort to diversify its nuclear fuel chain. An additional spent fuel interim storage facility is being constructed, and the country is cooperating with Westinghouse on fuel supply.37

DECOMMISSIONING WASTE

Once a nuclear power plant is closed, the spent fuel has to be removed, cooling systems and moderators drained. The process of defueling, deconstruction, and dismantling of a nuclear power plant is called decommissioning.38 The IAEA estimates the mass (rather than volume) of the decommissioning waste: a light-water reactor with 1 GW can be expected to produce 5,000 to 6,000 tons of LILW and 1,000 tons of long-lived LILW and HLW.39 This estimate has to be taken with caution as only one reactor as big as 1 GW has been decommissioned worldwide yet but this reactor (Trojan in the US) was only operational for 17 years. As of 2018, only 19 (smaller) nuclear power plants or about 6 GW have been decommissioned worldwide (see Table 1).40 Similar to operational waste, the quantity of decommissioning waste depends on various factors, such as the clearance level of waste, the decommissioning strategy (immediate dismantling or long-term enclosure), the operating time, and the specific reactor technology. The waste produced in the initial stages of decommissioning has the same characteristics as operational waste and can be characterized using the same approach, with one exception: it is generated in much larger quantities in a shorter period of time.41

35 IAEA 2019 36 Over 100 years compared to uranium fuels or much greater volume in disposal sites (about a factor of 3). For a detailed discussion of comparative volumes see Mycle Schneider and Yves Marignac, “Spent Nuclear Fuel Reprocessing in France”, IPFM, April 2008. 37 International Panel on Fissile Materials 2018, “Ukraine to explore reprocessing its spent fuel in France”, 3 May, viewed 12 June 2019, http://fissilematerials.org/blog/2018/05/ukraine_to_explore_reproc.html 38 Schneider et al. 2018, World Nuclear Industry Status Report 2018. 39 IAEA, Estimation of Global Inventories of Radioactive Waste and Other Radioactive Materials, pp.16. 40 Schneider et al. 2018, World Nuclear Industry Status Report 2018. 41 IAEA, 2007