Office for Nuclear Regulation

Annual figures for holdings of civil unirradiated plutonium as of 31 December 2017

National totals as of 31 December 2017 (Previous year’s figures in brackets) Rounded to 100 kg plutonium with quantities less than 50 kg reported as such
Tonnes
1. Unirradiated separated plutonium in product stores at reprocessing plants 132.0 (129.3)
2. Unirradiated separated plutonium in the course of manufacture or fabrication and plutonium contained in unirradiated semi-fabricated or unfinished products at fuel or other fabricating plants or elsewhere 0.7 (0.8)
3. Plutonium contained in unirradiated MOX fuel or other fabricated products at reactor sites or elsewhere 2.0 (1.9)
4. Unirradiated separated plutonium held elsewhere. 1.4 (1.5)
Total 136.1 (133.5)
Note:
1. Plutonium included in lines 1-4 above belonging to foreign bodies. 23.1 (23.2)
2. Plutonium in any of the forms in lines 1-4 above held in locations in other countries and therefore not included above 0.0 (0.0)
3. Plutonium included in lines 1-4 above which is in international shipment prior to its arrival in the recipient State. 0.0 (0.0)

Estimated amounts of plutonium contained in spent civil reactor fuel - United Kingdom

National totals as of 31 December 2017 (Previous year’s figures in brackets) Rounded to 1000 kg plutonium with quantities less than 500 kg reported as such
Tonnes
1. Plutonium contained in spent fuel at civil reactor sites 10 (11)
2. Plutonium contained in spent fuel at reprocessing plants. 17 (18)
3. Plutonium contained in spent fuel held elsewhere. Less than 500 kg
(Less than 500 kg)
Total 27 (26)

Note

The treatment of material sent for direct disposal will need further consideration when specific plans for direct disposal have taken concrete form.

Definitions

Annual figures for holdings of civil high enriched uranium (HEU)* - United Kingdom

National totals As of 31 December 2017 (Previous year’s figures in brackets)
1. HEU stored at enrichment plants 2 kg (2 kg)
2. HEU at fabricating plants or at other reprocessing facilities 329 kg (372 kg)
3. HEU at civil reactor sites Less than 500 kg
(Less than 500 kg)
4. HEU at locations other than civil reactor sites, enrichment fabricating and reprocessing plants (e.g. laboratories, research centres) 772 kg (858 kg)
5. Irradiated HEU at civil reactor sites 5 kg (5 kg)
6. Irradiated HEU at locations other than civil reactor sites 132 kg (132 kg)
Total 1,241 kg (1,370 kg)

* The definition of high enriched uranium (HEU) is uranium enriched to 20% or more in uranium 235

Annual figures for holdings of civil depleted, natural and low enriched uranium (DNLEU) in the nuclear fuel cycle - United Kingdom

National total As of 31 December 2017 (Previous year’s figures in brackets)
DNLEU 119000 tonnes** (126700 tonnes)**

** To nearest 100 tonnes