The safety of EDF Energy’s nuclear plants

1. The safety of EDF Energy’s nuclear plants 1 Version 2, 06 April 2011 NOT PROTECTIVELY MARKED

2. Key events at Fukushima • March 11: • North Eastern coast of Japan hit by a large earthquake measuring 9 on the Richter scale. The Fukushima Daiichi plant stopped automatically when the earthquake occurred and all post shut down systems started to operate normally. • The site was then hit by a tsunami measuring over 12m high that flooded the site and caused the loss of plant cooling capacity at the station. • March 12 • Explosion in reactor 1 • March 14 • Double explosion of hydrogen in reactor 3 • March 15 • Another explosion in reactor 2 and fire in reactor 4 Fukushima Daiichi has six boiling water reactors (BWR)

3. Support for Japan Support from EDF Energy has been given and offered through a number of means: • EDF Group is monitoring the situation closely. We are preparing to send experts as required through the World Association of Nuclear Operators. We are also providing nuclear expertise to the Foreign and Commonwealth Office and other official bodies • We have made available • 95 tonnes of boric acid to Japan. Boric acid is a neutron absorbing substance that stops criticality taking place • robots • detection systems • radioprotection equipment • In total 130 tonnes of equipment made available by EDF and Areva has been flown out to Japan, with the required accompanying personnel. • EDF Group is providing support to TEPCO to get power networks back up and running as soon as possible. ERDF (the networks division of EDF) is fully involved with these efforts. • EDF Energy has also provided iodine tablets for the British and Commonwealth Foreign Office (FCO) • We remain on standby to supply other support as required

4. Review of our position • Special meeting of the British Energy Generation Licensee Board was called • It was agreed that the plants are safe to operate as normal given the low earthquake risk in the UK, the plants being designed to withstand credible earthquakes and tsunamis, and the design enhancements at Sizewell B compared to earlier PWRs • Agreed to cooperate fully and proactively with the review of UK nuclear stations (ordered by Chris Huhne, Secretary of State) to be conducted by the UK regulator, the NII • Placed an action to thoroughly review all systems and processes and to check that all back-up systems are in good physical condition • Company emergency response centre established to co-ordinate communications and support • A number of actions were agreed at our plants in the light of information from Japan.

5. Our nuclear plants in the UK • We own and run eight nuclear power stations (15 reactors) in the UK with a combined capacity of almost 10,000 megawatts • We operate two types of nuclear reactor: advanced gas-cooled reactor (AGR) and a pressurised water reactor (PWR) • Seven of our nuclear power stations (14 of our reactors) are of the AGR design, whilst the remaining station (one reactor), Sizewell, is a PWR • None of the UK plants are of the Fukushima BWR type.

6. Safety is our number one priority It is our duty to ensure the safety of the public, our employees, our power stations and the environment In the nuclear industry we ensure the safety of our plant and aim to achieve a high standard of performance from our people through: • Safety in design – built-in multiple safety systems • Regulation – nuclear power is a very highly-regulated industry and Existing Nuclear places great emphasis on a ‘safety first’ culture. • Training – continuous improvement leads to organisational excellence. We want our staff to be inspired and engaged, to raise their own standards and those of others, and to continually improve on personal performance.

7. Key safety principles • Our power stations are designed under the principles of ‘strength in depth’ – this means we are never reliant on a single protection system • In our approach we use three concepts: • Diversity – different designs of protection systems to avoid common mode failure • Redundancy – having multiple systems available where only one is required • Segregation – housing your systems in multiple locations so that you never lose them all in one event • For example: • At Heysham 2 (AGR) there are four diesel houses, each containing multiple generators of different designs, located at the four corners of the reactor building. Each generator can support the required supply of electricity for the reactor. • At Sizewell B (PWR) there are four separate buildings housing multiple generators and battery charging diesels to support the required supply of electricity for the reactor. • In both situations if we were to lose national grid power to the station and should we lose the electricity supply from one generator, there would be alternative generators that would provide the required power according to the principles described above.

8. Advanced gas-cooled reactor (AGR) • This is the type of reactor operated by Existing Nuclear at seven sites and is unique to the UK • The reactor and steam generators are housed within a steel reinforced concrete pressure vessel, the walls of which are several metres thick

9. Pressurised water reactor (PWR) • This is the most common type of commercial reactor - nearly 60% of the world's commercial reactors are PWRs, including the Sizewell 'B' plant in the UK • The reactor is encased in a concrete biological shield within a secondary containment building.

10. Boiling water reactor (BWR) • BWR is the second most common type of electricity-generating nuclear reactor after the pressurized water reactor (PWR) • In the UK none of our plants are of the Fukushima BWR type.

11. Flood and seismic protection Flood protection • All the plants are protected against credible storm surge and tsunami events for the UK • If they were hit by the worst storm or tsunami or flood that could be expected in the UK in 10,000 years, our plants would be safe. Seismic protection • An earthquake the size of the one in Japan is not credible in the UK. Earthquakes of the size of the Japanese earthquake can only occur in zones where tectonic plates collide - the UK is located in the middle of a tectonic plate • All our plants are protected against the effects of a 1 in 10,000 years earthquake. That means even if they were hit by the worst earthquake or tsunami that could be expected in 10,000 years, our plants would be safe • These measures are detailed in approved safety cases which are tested and agreed with the independent safety regulator (NII).

12. Independent regulation • The UK nuclear industry is regulated by the Nuclear Installations Inspectorate (NII) in England (part of the Health & Safety Executive) and the Environment Agency (SEPA in Scotland) • They ensure that every nuclear plant has access to emergency power supplies should connection to the grid fail - and that back-up plans are robust • The regulator (NII) has said that it is confident that the UK’s fleet of nuclear power reactors and operators are prepared appropriately for any seismic activity that could be anticipated in the UK • Preparedness for seismic activity is examined and inspected by UK regulators during 10-yearly periodic safety reviews (PSR) and continuously through the year as required • Our older plants have been subject to various modifications and enhancements via this PSR process over the years.

13. Open reporting culture EDF Energy has an open reporting culture and works closely with the safety, environmental and security regulators, and the communities around our sites, to ensure we are meeting all our commitments in respect of openness and transparency    This culture of open reporting is the bedrock of our organisation, it is the foundation upon which we base all our operations We encourage our staff to flag up any issues that may impact on our operations, no matter how minor or trivial they may appear. We have a specific programme that exists to ensure these issues are captured and dealt with effectively The nuclear industry is very unusual in the way that it openly shares information across the globe. Through international organisations such as the World Association of Nuclear Operators we share information so that we can learn from the experience of others Every site holds regular community liaison meetings and proactively brief the community on any events that have taken place on the sites.

14. Protecting the public Part of our emergency arrangements is to inform local residents of actions that should be taken should a nuclear emergency arise at one of the power stations The Radiation (Emergency Preparedness & Public Information) Regulations 2001 (REPPIR) requires us to warn and inform local residents of the risks and required action in an emergency To do this we produce calendars each year for residents living within 3km of the power station. These have the emergency advice on the reverse so it can be easily located  All our stations operate a telephone warning system for local people The aim is to give as much information as possible, including the local radio stations and television channels to tune in to, and advice on action to take in an emergency

15. Emergency planning zones Routine monitoring of foodstuffs Planning Zone Outline Emergency planning zone 40km Detailed Emergency Planning Zone 15km • Up to 3km from site: • Detailed plans developed • Emergency calendars distributed • Potassium iodine tablets distributed • Station telephone warning system in operation • Up to 15km from site • Arrangements in place if required • Mobile radiation monitoring vehicles available • Up to 40km from site • Routine monitoring of foodstuffs and the environment. 15

16. Emergency exercises Every power station has fully developed emergency plans that are agreed with our regulators Demonstration exercises take place on each site annually Full scale demonstration exercises involving the emergency services, local authorities and government departments take place every three years Exercises are independently audited by our regulator

17. What is radiation? Radiation is an entirely natural phenomenon, something we all live with safely every day. Radiation comes from the earth, outer space, the sun; and it occurs naturally in food and drink Around 84% of the radiation we routinely receive comes from natural sources; the rest is artificial and arises mostly from medical treatment According to a 2005 review by the Health Protection Agency, on average, employees at nuclear power stations could actually receive a lower typical annual radiation dose than some airline pilots and crew How much you receive depends on how you live and work, for example Cornwall is naturally more radioactive than, say, Norfolk because of the type of rock there Extremely low levels of radioactive iodine have been detected in the air in the UK by the Health Protection Agency.

18. Radiation facts and figures How much radiation are people exposed to in everyday life? (in millisieverts, which is the standard unit for measuring radiation) 0,002 Annual dose received when in the vicinity of a nuclear power plant 0,006 Dose received during a dental panoramic radiograph 0,03 Dose received during a flight from London to New York 0,3 Dose received during a lung/chest radiograph/x-ray 0,3 Annual dose received due to radioactivity in food and water 8 Average annual background dose in areas of Cornwall due to the granite rock At what level does radiation become harmful (in millisieverts)? 100 Dose at which the first biological effects appear 500 Dose causing long term effects 1 000 Dose causing immediate clinical effects 4 000 Dose that is lethal if not treated in 50% of cases 7 000 Dose that is lethal in a few hours

19. Radiation exposure Average radiation dose exposures across different industries Annual radiation exposure from all sources (natural and artificial) Natural, 84% Artificial, 16% Radiation from the nuclear industry These figures are in addition to the average dose received by a member of the public which is 2.7 mSv/year. 19

20. Where to find more information • A special ‘Japan Update’ intranet site has been set up with: • Letters from Vincent de Rivaz • Company statements • Media statements and cuttings • Question and answer briefs • Follow the links on the intranet to find the site