NPP Safety in the aftermath of the Fukushima Accident. UK Response August 2013

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1 Health and Safety Executive NPP Safety in the aftermath of the Fukushima Accident Dr. Gary Cook UK Response August 2013

2 Overview ONR response to Fukushima ENSREG stress tests Specification and process Sizewell B PWR Sizewell B plant Outcome of stress tests Safety improvements AGRs AGR plant Outcome of stress tests Safety improvements National Action Plans and current status

3 ONR Response to Fukushima (1) UK nationals in Japan - securing the protection of people and society Incident Suite set up ran for two weeks sometimes 24hrs Advice to UK Chief Scientist Advisory Group and Highest levels of UK Government Prompt assurance of UK fleet Leading IAEA Mission to Japan & Fukushima Dai-ichi Chief Inspector s Interim Report to Secretary of State May 2011 Chief Inspector s Final Report to Secretary of State September 2011

4 ONR Response to Fukushima (2) Stress Tests NPP Final Report December 2011 Stress Tests Non Power Generating Nuclear Facilities May 2012 Stress Tests Peer Reviews Convention on Nuclear Safety May 2012 Implementation Report October 2012 National Action Plan December 2012

5 UK NPPs NPP / Defuelling site Reactor type Status Number of reactors Thermal power per reactor Date of start of construction Wylfa Magnox Operating MW 1963 Dungeness B AGR Operating MW 1965 Hinkley Point B AGR Operating MW Hunterston B AGR Operating MW Heysham 1 AGR Operating MW 1970 Hartlepool AGR Operating MW 1965 Torness AGR Operating MW 1979 Heysham 2 AGR Operating MW 1980 Sizewell B Westinghouse SNUPP PWR Operating MW 1988

6 UK Stress Tests (1) EDF Energy Nuclear Generation and Magnox Ltd issued Stress Test Reports one per station in October 2011 Raised Considerations items to be considered further and taken forward as appropriate Wide ranging: Site resilience Back-up equipment Emergency response Also took into account Chief Inspector s Recommendations

7 UK Stress Tests (2) ONR issued European Council Stress Tests for UK Nuclear Power Plants National Final Report, December 2011 Raised 19 Stress Test Findings (STFs) either reinforce or extend licensees Considerations or are additional to those identified by licensees Most STFs are applicable to all licensees/sites Some site specific eg STF 18 specific to Sizewell B concerns potential installation of filtered containment venting and passive autocatalytic hydrogen recombiners

8 Sizewell B Stress Tests - Overall Outcome Sizewell B response to Stress Tests generally good Margins evident in both seismic and flooding safety cases Appropriate levels of diversity and redundancy Some key improvements to increase on site resilience identified Focus on provision of backup equipment stored offsite

9 Key Safety Improvements Installation of Passive Autocatalytic Hydrogen Recombiners (PARs) commenced in 2013 outage, completion due in 2014 outage Installation of Filtered Containment Ventilation design options/feasibility studies in progress Sizewell B Emergency Response Centre (ERC)

10 Sizewell ERC Situated approximately 2 km off-site Will contain backup emergency control centre, filtered positive air pressure system, decontamination and welfare facilities, and storage of back-up equipment Construction started, planned completion end of 2013

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12 ERC - Backup Equipment (1) Secondary Circuit High pressure water pump (SG feed) Low pressure water pump (condensate storage tanks) Air compressor (clean air train system) Pond top-up Low pressure water pump Containment cooling Low pressure water pump

13 ERC - Backup Equipment (2) General response equipment Dewatering pumps Electrical generation sets Waste water management Damage repair equipment General logistics equipment Vehicles People movers All terrain vehicle haulage Debris removal Communications etc

14 Safety Improvements at Sizewell B (1) Mechanical Connection points Primary coolant Water tanks Clean air train system Auxiliary cooling Containment water injection penetration & pipe route

15 Safety Improvements at Sizewell B (2) Electrical Connection points Low Voltage Battery charging diesel generators Civil/Seismic Seismic qualification of fire station Securing of tanks within fixed jet fire pump building Control & Instrumentation (C&I) Emergency Response Monitoring System (C&I interfaces feasibility study)

16 Safety Improvements at Sizewell B (3) Flood protection Dam boards Building penetrations Remote inspection and cleaning of site drainage

17 AGRs Graphite moderated Coolant CO2, ~ 40 bar Fuel - uranium dioxide (UO2) pellets clad in stainless steel Pre-stressed concrete pressure vessel typically 30m diameter x 30m high, wall thickness 5-7m Low power density AGR~ 2.5 MWt/m3 PWR~ 100 MWt/m3 High thermal capacity ~ 1600 tonnes graphite Long timescale to core damage

18 AGR Stress Test Outcome AGR s response to stress tests good In most cases margins evident in both seismic and flooding safety cases Appropriate levels of diversity and redundancy High thermal inertia provides long timescale for operator action Some improvements to increase on site resilience identified Focus on provision of backup equipment stored offsite

19 EDF NGL Storage Strategy Local Depot 2 Location: Heysham (HEF) Provision: Partial (first wave) response for HY1 Regional Depot 3 Location: Fleet* Provision: 1 AGR response set (HPB / DNB); plus partial (second wave) response for SZB HNB HY1/HY2 HPB TOR Regional Depot 1 Location: Glasgow Provision: 1 AGR response set (HNB/TOR) HRA Regional Depot 2 Location: Carlisle Provision: 2 AGR response sets (HY1 + HY2 / HRA); plus national response SZB Local Depot 1 Location: Sizewell (ERC) Provision: 1 PWR response set 3 Regional AGR depots Containing 4 full response sets plus national equipment 2 Local depots SZB (deployment timescales) Heysham (station access, noting the timescales for HY1) The location of each regional facility considers: Driver resilience Deployment timescales Road access DNB

20 Recognised areas of good practice Examples of the back up equipment that will be demonstrated include:

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23 UK National Action Plan (UK NAcP) UK National Action Plan issued December 2012 provides update on progress made and has a structure consistent with ENSREG recommendations. ONR obtained data from licensees via: Technical, topic specific meetings Weekly update teleconferences Monthly project overview meetings Technical reports aligned to ONR recommendations and findings

24 Monitoring deliverables from the UK NAcP The Licensees will produce close-out reports as evidence that all technical aspects described in the UK NAcP have been completed. ONR will assess these reports and produce it s own final close-out report that will again be published on the ONR website. The current schedule is that work across the NPP s will be completed by mid The exceptions to this are on-going training programmes or work tied to plant outages.

25 Recognised areas of good practice The future nuclear emergency exercise program to test the on-site, off-site and central government responses for extended periods The multi site exercise planned for March This will also serve as a proof of concept exercise for back up equipment and associated arrangements.

26 Openness and Transparency All reports to date are available on the ONR website: Chief Inspector Interim Report Chief Inspector Final Report UK Stress Test Report Chief Inspector Interim Report UK National Action Plan

27 Conclusions Licensees have made good progress in addressing recommendations and findings from Fukushima work The majority of work will be complete by the 3 rd Anniversary of events at Fukushima There is alignment of strategy between ONR and licensees that centres around: Year 1 Assessing requirements Year 2 Procuring equipment Year 3 Delivery, installation, commissioning and demonstration