Publication Laka-library:
Review of UK and Overseas Depleted, Natural Low Enriched Uranium Management
Author | S.Doudou, E.J.Harvey |
6-01-5-50-95.pdf | |
Date | May 2014 |
Classification | 6.01.5.50/95 (WASTE - RADIOACTIVE WASTE GENERAL) |
Front |
From the publication:
Review of UK and Overseas Depleted, Natural Low Enriched Uranium Management S. Doudou and E.J. Harvey 19 May 2014 1207-INT-6-1 Version 1.3 Integrated Project Team on Uranium: Phase 2 [Task INT-6] Executive Summary An Integrated Project Team (IPT) comprising Nuclear Decommissioning Authority (NDA) Radioactive Waste Management Directorate (RWMD) staff and members of the supporting contractor base has been formed, to work collaboratively on the topic of depleted, natural and low-enriched uranium (DNLEU), focusing on the disposability and associated full lifecycle implications of managing the UK inventory of these materials through geological disposal (the “uranium IPT”). This document reports the outcomes of an international review of DNLEU management practices. The review collates information on current and planned activities in the UK and overseas, in order to inform work undertaken elsewhere by the uranium IPT. Worldwide DNLEU stocks arise mainly from uranium enrichment operations for nuclear fuel, with significant quantities also arising from reprocessing spent nuclear fuel (RepU), particularly in France and the UK. Russia, the US and France hold by far the largest stocks of depleted uranium (DU). DNLEU stocks held by these countries significantly exceed UK stocks. In most countries, including the UK, France, Russia, Japan and South Korea, DNLEU is considered to be a potential (or current) resource, and it is held in storage with this in mind. Some countries, notably France, reuse RepU within fuel rods for nuclear power plants, either as conventional uranium oxide (UOX) fuel, or within mixed-oxide (MOX) fuel. Approaches to package DNLEU for storage are similar across different countries. Depleted uranium hexafluoride (UF6) is typically stored in steel cylinders, as in the UK. Triuranium octoxide (U3O8) is regarded as the preferred chemical form for long-term storage and/or disposal in most countries. In the UK, deconverted U3O8 will be stored in DV-70 containers, as is also done in France, Germany, and the Netherlands. Transport of DNLEU stocks in a variety of chemical forms (including UF6, liquid uranyl nitrate, U3O8 and uranium trioxide (UO3) powders) is routinely undertaken in many countries. The materials are usually classified as Low Specific Activity (LSA) and industrial packages (IP) are used for their transport. The US is the only country that currently regards at least some DNLEU as a waste. The regulator classifies it as low-level waste (LLW), and regulatory policy provides for disposal of DNLEU in near-surface facilities. However, to date only relatively small quantities have been disposed of in this way at the existing sites. Japan has examined the possibility of near-surface disposal of some uranium-bearing wastes of low activity concentration in a trench-type facility. Germany is the only country that has assessed the performance of a geological disposal facility (GDF) for significant quantities of DU (in a salt dome at Gorleben). Some consideration has been given in US research projects to alternative (beneficial)uses of DU in a GDF. However, overall, there is relatively little transferable experience from overseas that is specifically relevant to geological disposal concept development for DNLEU in the UK.