New report provides insight into nuclear waste
The Nuclear Decommissioning Authority (NDA), the agency tasked with ‘managing nuclear waste generated through the clean-up of the UK’s civil nuclear legacy’, published a new report today (16 July) that aims to ‘help people understand activities that produce radioactive wastes in the UK’.
‘Understanding activities that produce radioactive wastes in the UK’ is split into two parts, the first of which provides an ‘introduction to radioactivity, an overview of key activities that produce radioactive waste, and information about how radioactive wastes are managed’.
The second part is comprised of a series of fact sheets, which provide additional detail ‘on the main activities and processes that create radioactive wastes’.
Nuclear waste origins
According to the NDA, radioactive waste is generated as a by-product of a number of UK industrial process such as: generating power; treating medical illnesses and conducting research; and via its utilisation in the defence sector.
For example, a typical commercial nuclear reactor in an energy facility contains around 100 tonnes of enriched uranium fuel, while spent fuel reprocessing produces a highly radioactive liquid that generates heat, alongside a number of other intermediate radioactive materials.
In all, 98 per cent of nuclear waste generated in the UK stems from the nuclear fuel cycle. The remaining two per cent is split evenly between the defence (through nuclear powered submarine fleet and nuclear weapons), medical (through radioactive isotope treatments), and industrial sectors (i.e. through biological sterilisation).
The report estimates that there is about 1,100 cubic metres (m³) of high-level waste (HLW) in the UK, 290,000m³ of intermediate-level waste (ILW), 1.4 million m³ of low-level waste (LLW), and 2.8 million m³ of very low-level waste (VLLW).
The majority of radioactive materials (91 per cent) are produced in England, six per cent in Scotland and three per cent in Wales. There are no major radioactive producers in Northern Ireland.
Disposal in the UK
LLW and VLLW is disposed in purpose built facilities, such as the LLW repository located south of Sellafield in Cumbria, and at a LLW repository at Dounreay in the north of Scotland.
Waste is typically mixed with cement and sealed in concrete-lined disposal ‘vaults’. In some cases, some LLW and VLLW can be disposed of at authorised landfill sites alongside other household, commercial and industrial wastes.
Currently there are no long-term facilities in the UK to dispose of ‘higher activity waste’, including HLW, ILW and a small amount of LLW that cannot be disposed in the LLWR.
Higher activity waste is currently converted into a stable form and then stored in ‘robust interim storage facilities’ until a long-term management solution is developed.
The government’s policy is to store the waste deep underground in a Geological Disposal Facility (GDF), with ‘multiple engineered barriers’ to prevent the material ever being released. However, the process to find a community willing to voluntarily host such a site has proved difficult, with government amending the law earlier this year so that it has final say on where a nuclear GDF can be sited.
Beth Ripper, NDA National Waste Inventory Manager, said that the report “will be helpful to people who are new to the nuclear sector, or who have a general interest in the topic”.