Friday, 22 April 2011

Nuclear Installations: Accidents: 8 Mar 2011: Written answers and statements (

Photo of Charles Hendry

Charles Hendry (Minister of State (Renewable Energy), Energy and Climate Change; Wealden, Conservative)

The Nuclear Installations Inspectorate of the Health and Safety Executive (HSE/NII) screens incident reports made by licensees to identify those which have had the potential to challenge a nuclear safety system. A search of the raw input data for such screening from January 2005 to the end of December 2010 has been undertaken for details of leaks and fires at nuclear installations.

A 'coolant leak' has been interpreted as being a loss of coolant, including clean coolant, from an item of plant into the working environment of the licensed site. Coolant itself has been interpreted as being water, carbon dioxide or hydrogen on a power station, and water elsewhere.

A 'fire' has been interpreted as being a situation where ignition of material has taken place on the licensed site or instances of smouldering where such ignition could not reasonably be ruled out given the information in the record.

Coolant leaks
Date Installation Incident
1 January Heysham 2 Steam leak on Turbine Generator 7
5 February Hinkley Point B Carbon dioxide leak from tank
19 February Hinkley Point B Carbon dioxide leak from tank
25 February Torness Carbon dioxide leak through in-service inspection penetration
15 March Torness Carbon dioxide leak from ring main
25 June Dungeness A Carbon dioxide leak from main CO2 plant
4 July Sellafield Damp patch discovered adjacent to B30 pond wall
25 July Oldbury Steam leak through thermocouple pocket of Boiler 4 on Reactor 1
4 August Hinkley Point B Carbon dioxide leak from vaporiser valve
30 October Dungeness A Carbon dioxide leak through failed isolation valve to pressure gauge
30 January Sellafield Leak of dosed cooling water from B832 cooling tower
18 February Sellafield Leak of pond water through expansion joint above the stainless steel seal in B310 AGR storage pond
24 March Hunterston B Carbon dioxide leak in pipe trench
11 September Hinkley point B Carbon dioxide leak from supply pump
23 September Hartlepool Alternator hydrogen coolant leak
26 September Hartlepool Fracture of emergency cooling water main
2 October Dungeness B Auxiliary cooling water pipe work leak
15 October Sizewell A Steam leak from Turbine Alternator 1
18 November Heysham 2 Steam leak from Reactor 7
7 January Sizewell A Fracture of pond recirculating water system pipe work
18 January Sellafield Waste Vitrification Plant electrical inductor cooling water leak
1 March Hinkley Point B Carbon dioxide leak outside plant room
26 March Dungeness B Carbon dioxide leak in reactor basement
1 June Hunterston B Leak from condensate booster pump
2 June Heysham 2 Leak in low pressure feed heater pipe work
18 July Dungeness B Leak of tritiated water identified
19 September Hartlepool Leak of pressure vessel cooling water identified on boiler closure unit
26 September Dungeness B Carbon dioxide leak from storage tank
28 September Hunterston B Steam leaks in high pressure gland pipe work
27 October Oldbury Carbon dioxide leak from fuelling machine
19 February Oldbury Carbon dioxide leak from storage tank
20 February Torness Carbon dioxide leak from gas bypass plant
26 June Heysham 2 Steam leak in gland steam drain line
26 July Heysham 1 Carbon dioxide leak from storage tank
7 October Wylfa Carbon dioxide leak from storage tank
23 December Torness Carbon dioxide leak from valve in the fuel machine standby CO2 coolant supply.
24 April Hartlepool Hydrogen leak from Unit 2 alternator frame
26 May Heysham 1 Turbine cooling water leak
28 May Hinkley Point B Pressure vessel cooling water leak from Reactor 4 sump
25 June Heysham 2 Loss of Hydrogen from turbo alternator
8 July Torness Leak from spent fuel pond cooling water system
9 December Sellafield Fuel pond chiller water leakage
21 December Heysham 1 Back up cooling water leak soon after start up
22 January Sellafield Leakage of cooling water to active storage tanks
7 June Dungeness B Gland steam leak after start up
26 October Heysham 1 Small water leak from buffer store drain line
8 November Heysham 1 Emergency cooling water pipe failure and leak
Date Site Incident
4 February Heysham 1 Smouldering lagging on turbine
8 March Heysham 2 Fire on reactor basement sump pump
22 April Harwell Capacitor fire in building 459
22 June Torness Variable frequency output transformer fire
30 June Barrow Portacabin fire
14 July Heysham 2 Fire in bearing of fuel handling plant extract fan
16 September Torness Fire in purge air compressor no. 2
31 October Dungeness A Fire in bulk group 4 LF power supply
23 January Sellafield Smoking bitumen seal around pipe on Combined Heat and Power Plant turbine
24 March Dounreay Hydrogen ignition during waste cutting operation in Prototype Fast Reactor
21 April Springfields Uranium shredder fire in building 338
23 October Heysham 2 Smouldering leak management tray beside hot turbine reheat pipe work
23 December Burghfield Smouldering cable in plant room
1 February Hinkley Point B Fire in bund of gas circulator lube system
2 June Hunterston B Bearing fire on turbo generator 7
12 August Heysham 2 Bearing fire in cooling water pump
7 January Dounreay Fire in office suite of D1208
13 March GE Healthcare Fire in inactive recycling plant
15 June Rolls Royce Manufacturing Fire in glove box
2 December Hartlepool Aerosol can fire
3 December Trawsfynydd convector heater fire in ponds office
12 March Heysham 1 Lagging smoke/fire
15 March GE Healthcare Fire in services spine duct
31 March Barrow Fire on the casing of Astute Boat 2 during welding/grinding operations
18 April Barrow Fire on the bridge fin of Astute Boat I
29 April Oldbury Smoking air circuit breaker
18 May Wylfa Fire in Turbine alternator
22 July Sellafield Extract fan bearing fire
23November Dungeness B Boiler annex hydraulic fluid caught fire
28 May Dounreay Small in cell fire of sodium residues
2 July Sizewell B Fire in ductwork in heating and ventilation building
4 July Aldermaston Solvent fire minor bums to one person
2 August Oldbury Lagging fire near turbo alternator
22 September Sizewell B Condensate pump fire
30 September Wylfa Smouldering electrical contactor in Turbine Hall
25 October Hinkley Point B Fire in circulator workshop
8 December Heysham 2 Bearing failure causing smoke in services building