Nuclear and Radiological Regulatory Authority Egypt - ENRRA Egypt Research and Reactors Design Safety Approach

Technical Meeting on the Evaluation of Design Safety In the Aftermath of the Fukushima Daiichi Accident

26-29 August 2013 Vienna, Austria

EL-MESSIRY Ahmed Egypt Nuclear and Radiological Regulatory Authority ENRRA [email protected]

29 August 2013 1 Nuclear and Radiological Regulatory Authority Egypt - ENRRA AUTHER RESUME  B.Sc., M.SC., Ph. D. in ,  Prof. of nuclear installation safety,  Board Member of Egypt Nuclear and Radiological Regulatory Authority ,(2012- now),  Sharing in editing Egypt nuclear law and its executive regulation,  Member of Review & Assessment of nuclear installations committee, and Nuclear installation Operators licensing committees,  Reactor operator of Egypt Test and Research Reactor # 1, (1969-1982).

29 August 2013 2 Nuclear and Radiological PAPER OUTLINE: Regulatory Authority Egypt - ENRRA 1- INTRODUCTION

2- EGYPT NUCLEAR SAFETY APPROACH OF NUCLEAR REACTORS

3- GENERAL DESIGN SAFETY ASPECTS OF NUCLEAR REACTORS

4-FUKUSHIMA ACCIDENT ANALYSES

5- DIFFERENT IMPOVMENTS IN PLANT SYSTEM AS A RESULT OF FUKUSHIMA ACCIDENT

6- FEEDBACK OF FUKUSHIMA ACCIDENT ON SAFETY OF NUCLEAR REACTORS IN EGYPT 29 August 2013 3 Nuclear and Radiological 1. INTRODUCTION Regulatory Authority Egypt - ENRRA

The main articles relating to the nuclear platform (infrastructures) of Egypt are:

1.1 Nuclear Organizations, 1.2 Regulatory Body, 1.3 Nuclear power program, 1.4 Nuclear reactors, 1.5 Regulation used in licensing nuclear reactors.

29 August 2013 4 Nuclear and Radiological 1. INTRODUCTION Regulatory Authority Egypt - ENRRA

1.1. Nuclear Organizations in Egypt i. Atomic Energy Authority AEA (Operates two research reactors), ii. Nuclear Power Plant Authority NPPA (Responsible for establishing nuclear power program), iii. Nuclear Material Authority NMA (milling and mining of nuclear materials), iv. Nuclear and Radiological Regulatory Authority NRRA ( Regulate all nuclear and radiation facilities and activities inside the country).

29 August 2013 5 Nuclear and Radiological 1. INTRODUCTION Regulatory Authority Egypt - ENRRA 1.2. Regulatory Body o In 1983, a national center for nuclear safety and radiation control NC-NSRC was established under the umbrella of EAEA – ministry of electricity, it worked under the law 59 of year 1960, hence it was dependent, o In March 2010, A new nuclear law 7 of year 2010 was issued, it replaced the law 59 of year 1960, it stated a necessity of establishing independent regulatory body, o in November 2011, an executive regulation of the nuclear law 7 of year 2010 was issued, o On 5/3/2012, an independent regulatory body was established which replaced the old NC-NSRC, it had the name ENRRA, it reported directly to the prime minister,

29 August 2013 6 Nuclear and Radiological 1. INTRODUCTION Regulatory Authority Egypt - ENRRA 1.3. Nuclear power program o In 1979, Egypt planned a nuclear power program, of 4 nuclear power plant, each of two units, o In 1980, NPPA was established to take over the program, o In 1986, the plan stopped due to Chernobyl accident, o In 2008 the program reinitiated and the site was selected on the seashore of Middetrainian sea, west of Alexandria city, o In 2009, ENRRA submitted a site design requirements and environmental impact assessment report contents to NPPA, which in turn sent the site safety analysis report, it reviewed and assessed,

29 August 2013 7 Nuclear and Radiological 1. INTRODUCTION Regulatory Authority Egypt - ENRRA 1.3. Nuclear power program o In 2011, and due to Fukushima accident, the site design requirements were modified to cope with the resistance of the plant to high earthquakes and flooding , o In 2012 and due to Fukushima accident, safety design requirements of the plant were modified and sent to NPPA, it included addition of a portable emergency power supply, hydrogen re-combination, and cooling water tanks. o In 2012 NPPA prepared a plant technical specifications with the new modification for international bid , o The proposed plant will compose of two units of light water pressurized reactors PWR, with electric power output in the range 1200 : 1600 MWe for each unit ,

29 August 2013 8 Nuclear and Radiological 1. INTRODUCTION Regulatory Authority Egypt - ENRRA

1.4. Nuclear reactors EAEA operates two Reactors: i- Egypt Test and Research Reactor #2 ,ETRR#2, This an MPR used for:  Isotopes production Mo, TC, Ir, I, Cr,  Co 60 production,  activation analysis,  Radiotherapy by thermal neutron capture,  Material irradiation,  Research, o It was built By Argentina, went critical on 1997, o 22 Mw, 20% U235 enrichment, plate type fuel , water cooled and moderated, Beryllium reflector, o Two safety shutdown system, o Open pool type.

29 August 2013 9 Nuclear and Radiological 1. INTRODUCTION Regulatory Authority Egypt - ENRRA

1.4. Nuclear reactors ii- Egypt Test and Research Reactor # 1, ETRR#1, This an Russian type reactor used for:  Neutron irradiations,  Radioisotope production,  Research, o It is an turn key project, went critical on 1963, o 2 Mw, 10% U235 enrichment, rod type fuel , water cooled and moderated, Graphite reflector o One safety shutdown system, o Closed tank type.

29 August 2013 10 Nuclear and Radiological 1. INTRODUCTION Regulatory Authority Egypt - ENRRA

1.5. Regulation used in licensing nuclear reactors  Due to the incomplete national regulatory documents framework, ENRRA do review and assessment and licensing of nuclear reactors as follows:

A- For power plant we used: i. Up to date versions of IAEA standards as SF-1, GSR part 1 : 6, SSR 2-1 , SSR-2-2, GS-R-3, SSG-2, SSG-12, SSG-16, SSG-22, SSG-25, INSAG series No 10,12, 16,17, 22, 46, ii. US-NRC standards as NUREG 1.7, iii. National regulations.

29 August 2013 11 Nuclear and Radiological 1. INTRODUCTION Regulatory Authority Egypt - ENRRA

1.5. Regulation used in licensing nuclear reactors B- For Research Reactors we used: i. IAEA safety standards as safety series SS- 35 S1,S2, G1, G2 , Service series 1 and 2 , INSAG 3 and recently NS-R-4 with its guides NS-G-4.1:4.6, SSG-20, ii. International standards as US-NRC regulatory guides NUREG 1537 I and II, iii. The vendor country standards (Argentina), iv. Egyptian regulations.

29 August 2013 12 2. EGYPT NUCLEAR Nuclear and radiological SAFETY APPROACH OF Regulatory Authority NUCLEAR REACTORS Egypt - ENRRA 2.1. Safety Fundamentals and principles

Safety fundamentals

Objectives Principles

General specific

Management Strategy of Defense in Technical depth

29 August 2013 13 2- EGYPT NUCLEAR Nuclear and radiological SAFETY APPROACH OF Regulatory Authority NUCLEAR REACTORS Egypt - ENRRA 2.2. Methodology  The review and assessment R&A Methodology follows basically the concept of defense in depth and placing most emphasis on accident prevention,  Safety analysis remains an important part in R&A, it basically follow a deterministic approach with support of probabilistic analysis,  Many unexpected accident with very low probabilities should be analyzed,  International cooperation should be considered, especially in technology transfer in all aspects of nuclear safety. 29 August 2013 14 2- EGYPT NUCLEAR Nuclear and Radiological SAFETY APPROACH OF Regulatory Authority NUCLEAR REACTORS Egypt - ENRRA 2.3. Principles The main principle is strategy of Defence in Depth Multiple levels of protection is the central feature of defence in depth.

This principle states " "To compensate for potential human and mechanical failures, a defence in depth concept is implemented, centered on several levels of protection including successive barriers preventing the release of radioactive material to the environment. The concept includes protection of barriers by averting damage to the plant and to the barriers themselves. It includes further measures to protect the public and the environment from harm in case these barriers are not fully effective".

29 August 2013 15 2- EGYPT NUCLEAR Nuclear and Radiological SAFETY APPROACH OF Regulatory Authority NUCLEAR REACTORS Egypt - ENRRA 2.4. Adopted Rules in safety assessment (a) The effect of single, random failures; (b) System qualification (or lack of qualification) under accident conditions; (c) Safety and protection systems, including reliability in quantitative terms; (d) Support systems, such as normal and emergency electric power and the cooling water; (e) Redundant trip parameters; (f) Actions of systems that are independent; (g) Operator action (e.g. response time, display of information on a console); and (h) Carrying out of frequency or probability evaluations to assess the system response,

29 August 2013 16 3. GENERAL DESIGN Nuclear and Radiological SAFETY ASEPCTS OF Regulatory Authority NUCLEAR REACTORS Egypt - ENRRA

3.1. Passive Nuclear Safety  It does not require operator actions in order to carry out its safety function,  IAEA classifies the degree of "passive safety" of components from category A to D depending on what the system does not make use of:  no moving working fluid,  no moving mechanical part,  no signal inputs of 'intelligence‘,  no external power input or forces.

29 August 2013 17 3. GENERAL DESIGN Nuclear and Radiological SAFETY ASEPCTS OF Regulatory Authority NUCLEAR REACTORS Egypt - ENRRA 3.1. Passive Nuclear Safety Example of a safety system with 'passively safe' components are:  The concrete walls and the steel liner of the containment,  The fuel cladding,  The surge line which connects the hot leg with the pressurizer,  The accumulator, which does not need signal input or external power,  The valves open and water is injected into the primary circuit by compressed nitrogen,  SCRAM which utilizes moving working fluids, and signal inputs but not external power or forces,  Control rods drop driven by gravity.

29 August 2013 18 3. GENERAL DESIGN Nuclear and radiological SAFETY ASEPCTS OF Regulatory Authority NUCLEAR REACTORS Egypt - ENRRA 3.2. Inherent Safety  Negative Temperature,  of reactivity,  The “AP 1100 standing for "Advanced Passive") uses passive safety components. In the event of an accident, no operator action is required for 72 hours,  Recent version of the Russian VVER have added a passive heat removal system to the existing active systems, utilising a cooling system and water tanks built on top of the containment dome.

29 August 2013 19 3. GENERAL DESIGN Nuclear and Radiological SAFETY ASEPCTS OF Regulatory Authority NUCLEAR REACTORS Egypt - ENRRA 3.3. Hydrogen Explosion  Hydrogen is formed by radiolytic decomposition of water,  This needs to be dealt with to avoid the explosion with oxygen present,  Reactors have been retrofitted with passive autocatalytic hydrogen recombiners in their containment,  In early boiling water types, the containment is rendered inert by injection of nitrogen,  At Fukushima the fuel became very hot, a lot of hydrogen is formed by the oxidation of zirconium fuel cladding in steam at about 1300°C,  This is beyond the capability of the normal hydrogen recombiners to deal with, and operators must rely on venting to atmosphere or inerting the containment29 August 2013 with nitrogen. 20 3. GENERAL DESIGN Nuclear and Radiological SAFETY ASEPCTS OF Regulatory Authority NUCLEAR REACTORS Egypt - ENRRA

3.4. Limits the Consequence of Accidents

 Timely detection of any Incident and Accident,  Provision of appropriate Engineered Safety Features and supporting systems to limit the consequences of an Incident or Accident,  Application of ergonomics principles and techniques to the design of the man-machine interface,  Provision of suitable procedures to enable the operators to act as required for nuclear safety and, to reinforce automatic actions relevant to safety,

29 August 2013 21 3. GENERAL DESIGN Nuclear and Radiological SAFETY ASEPCTS OF Regulatory Authority NUCLEAR REACTORS Egypt - ENRRA

3.4. Limits the Consequence of Accidents  Provision of preventive and mitigatory features for severe accidents, the management of safety, plant ageing and wearing out effects, computer based safety systems, external and internal hazards, human factors, feedback of operating experience, and safety assessment and verification,  Provision of Barriers against fission-product release,  Periodic Safety Review should be implemented to an existing nuclear power plant of all important aspects of safety, carried out at regular intervals, typically every ten years.

29 August 2013 22 4. SAFETY ANALYSIS OF Nuclear and Radiological FUKUSHIMA ACCIDENT Regulatory Authority Egypt - ENRRA 4.1. Accident Sequence 1. Earthquake, 2. Reactor Auto Trip & Loss of Site Power, 3. Emergency D/G Start up, 4. EDG Stop by Tsunami, 5. Station Black Out, 6. Fuel Heated by Cooling Failure, 7. Hydrogen Explosion.

29 August 2013 23 4. SAFETY ANALYSIS OF Nuclear and Radiological FUKUSHIMA ACCIDENT Regulatory Authority Egypt - ENRRA

4.2. Design safety Analysis . The reactors shutdown safely due to Earthquake, . The emergency core cooling system starts effectively, and operated for about 40 minutes, until it stopped by Tsunami, . The design basis Tsunami height was 5.7 m, but it comes with ashore height of 14 meters, . Therefore a high wall must be constructed to stop tsunami, . Another method must be relied upon as gravity, in case of failure of EDG, . Cooling requires water circulation and an external heat sink Station,

29 August 2013 24 4. SAFETY ANALYSIS OF Nuclear and radiological FUKUSHIMA ACCIDENT Regulatory Authority Egypt - ENRRA 4.2. Design safety Analysis . Hence there is provision for relieving pressure, sometimes with a vent system, but this must work and be controlled without power, . The venting system need to be such that they do not block due to solids being carried, e.g. using filters or scrubbers, . Ideally any vent system should deal with any large amounts of hydrogen, and have minimum potential to spread radioactivity outside the plant.

29 August 2013 25 4. SAFETY ANALYSIS OF Nuclear and Radiological Regulatory Authority FUKUSHIMA ACCIDENT Egypt - ENRRA 4.3. Results from the safety Analysis  Possibility for combination of two initiating events. earthquake and flooding,  Combined consequences: loss of electrical power and station blackout, loss of ultimate heat sink,  Provisions in the plant design basis for those events and the strength of the plant beyond its design basis, . Provision of the "design margins, diversity, redundancy, structural protection and physical separation of the safety relevant systems, . Effectiveness of the defence-in-depth concept,  Focus on 'cliff-edge' effects, e.g. when back-up batteries are exhausted and station blackout is inevitable.

29 August 2013 26 4. SAFETY ANALYSIS OF Nuclear and Radiological Regulatory Authority FUKUSHIMA ACCIDENT Egypt - ENRRA 4.3. Results from the safety Analysis  Identify the time before fuel damage is unavoidable and the time before water begins boiling in used fuel ponds and before fuel damage occurs,  Measures to prevent hydrogen explosions and fires should be part of this,  Assessing natural hazards and margins beyond design basis,  Importance to periodic safety reviews and evaluation of natural hazards, 29 August 2013 27 4. SAFETY ANALYSIS OF Nuclear and Radiological Regulatory Authority FUKUSHIMA ACCIDENT Egypt - ENRRA 4.3. Results from the safety Analysis  Measures to protect containment integrity,  Measures to prevent and mitigate accidents resulting from extreme natural hazards,  Addition of equipment to help respond to the loss of all electrical power and the loss of the ultimate heat sink for cooling,  Improved water level and temperature instrumentation on used fuel ponds.

29 August 2013 28 4. SAFETY ANALYSIS OF Nuclear and Radiological FUKUSHIMA ACCIDENT Regulatory Authority Egypt - ENRRA

4.3. Main Results from Fukushima safety Analysis Attention being given to:  Sitting criteria,  Design of back-up power,  Post-shutdown cooling,  Provision for venting the containment of that kind of reactor,  Provision of emergency management procedures.

29 August 2013 29 5. Improvement of plant Nuclear and Radiological system as a result of Regulatory Authority Fukushima Egypt - ENRRA Main Improvements  Incorporate automatic reactor shutdown system for earthquakes exceeding a certain seismic level (0.18g),  Reinforce the seismic capacity of the safe shutdown cooling system to the design earthquake level of advanced nuclear power plants (0.3g),  Raise the Sea Wall height of NPP to the height level of other NPP sites (10m),  Install waterproof gates and waterproof drainage pumps in major structures to prevent possible inundation,

29 August 2013 30 5. Improvement of plant Nuclear and Radiological system as a result of Regulatory Authority Fukushima Egypt - ENRRA Main Improvements  Equip one vehicle-mounted emergency generator per site in a safe place and Secure separate DC control power for flooding,  Expand the fuel supply capacity of alternative emergency diesel generator by considering multi-unit failure,  Install the Passive Hydrogen Removal Equipment (PHR) that can operate without any power supply,  Install filtered venting or depressurizing facility within the containment building.

29 August 2013 31 6. FEEDBACK OF FUKUSHIMA Nuclear and Radiological ACCIDENT ON UCLEAR Regulatory Authority SAFETY IN EGYPT Egypt - ENRRA

Nuclear reactors in Egypt: 1. Proposed nuclear power program, PWR Plant with two unit, 2. Egypt Test and research Reactor No 2 ETRR-2 , 3. Egypt Test and research Reactor No 1 ETRR-1 .

29 August 2013 32 6. FEEDBACK OF FUKUSHIMA Nuclear and Radiological ACCIDENT ON REACTOR Regulatory Authority SAFETY DESIGN IN EGYPT Egypt - ENRRA

6.1. Proposed nuclear power program,

 The site specific, free-field zero-period horizontal acceleration at ground level of the SL-2 increased from 0.27 to 0.3 g,

 Datum are at the coast +6.4 m, The main plant site elevation will be set at a minimum Elevation of 10 m to protect against flooding to elevation 8 m from the tsunami seawater level of 7 m plus an increased sea water level of 1 m due to tide,

 The sea water cooling system pumps shall be designed to accommodate the expected sea level fluctuation,

29 August 2013 33 6. FEEDBACK OF FUKUSHIMA Nuclear and Radiological ACCIDENT ON REACTOR Regulatory Authority SAFETY DESIGN IN EGYPT Egypt - ENRRA

6.1. Proposed nuclear power program,  The Operator shall identify the aircraft impact design basis for which the NPP is designed to accommodate. He shall demonstrate that the structures are adequate for: 1- Stability, 2- Scabbing of concrete surfaces, 3- Perforation,  The plant design shall take into account any man- made hazards in the proximity of the plant site that may occur as a result of development in the future,  The plant design shall incorporate protection against sabotage,

29 August 2013 34 6. FEEDBACK OF FUKUSHIMA Nuclear and Radiological ACCIDENT ON REACTOR Regulatory Authority SAFETY DESIGN IN EGYPT Egypt - ENRRA 6.2. ETRR#2  According to safety standards NS R 4 and NS G 4.1,2,3 , the new experiment with major safety significance should be approved by the regulatory body ENRRA,  ETRR-2 follows these regulations and submit to the regulatory body all the documents and updated safety analysis report,  Reactor core design changes due to implementing an project with major safety significance ( replacing two target of U plate inside the reactor core),  ENRRA review and assess the safety of the design changed neutronic and thermal-hydraulics ,  ENRRA issued a commissioning permit , and followed by operation license. 29 August 2013 35 6. FEEDBACK OF FUKUSHIMA Nuclear and Radiological ACCIDENT ON UCLEAR Regulatory Authority SAFETY IN EGYPT Egypt - ENRRA 6.3. ETRR#1  ETRR#1 is an 50 years old, WWR-C Russian type reactor,  In the past three years the reactor subjected to different accidents: water leak from the main heat exchangers, reduction of pool water level, pump failure leading to loss of coolant,  The reactor become old and need to repair, upgrade or decommissioned,  Now it is at extended shutdown,  Due to the risk on safety of maintaining the reactor at the new state, We require a mission of IAEA to assess its safety, April 2013.

29 August 2013 36 6. FEEDBACK OF FUKUSHIMA Nuclear and Radiological ACCIDENT ON UCLEAR Regulatory Authority SAFETY IN EGYPT Egypt - ENRRA 6.3. ETRR#1 IAEA expert mission advice:  Development of a feasibility study for a decision making concerning the future of this reactor, either to implement the necessary safety improvements or to proceed with its decommissioning,  Recommended improvements at the organizational level, including the human resources and their training and qualification ,  Considered that maintaining the current situation of the ETRR-1 is not satisfactory from the safety point of view. 29 August 2013 37 6. FEEDBACK OF FUKUSHIMA Nuclear and Radiological ACCIDENT ON UCLEAR Regulatory Authority SAFETY IN EGYPT Egypt - ENRRA 6.3. ETRR#1 ENRRA Activities  On Tune 2013, ENRRA inspects the reactor systems and analyze water samples from the reactor and storage pools,  The analyses showed a presence of Cs 134 and 137, higher than the permissible level, indicating a presence of failure in fuel clad,  ENRRA required from ETRR-1 to do an extended shutdown plan and resolve the problem of high radioactivity in the water pools.

29 August 2013 38 6. FEEDBACK OF FUKUSHIMA Nuclear and Radiological ACCIDENT ON UCLEAR Regulatory Authority SAFETY IN EGYPT Egypt - ENRRA 6.4. Others Issues AEA Side  stress in the training course of reactor operator on how to response, behave, interact with reactor systems in case of severe accidents,  Update the management system of both the two reactors to cope with the situation of unexpected accidents,  Carry out new safety review of both reactors, and put a schedule of periodic safety.

29 August 2013 39 6. FEEDBACK OF FUKUSHIMA Nuclear and Radiological ACCIDENT ON UCLEAR Regulatory Authority SAFETY IN EGYPT Egypt - ENRRA 6.4. OTHERS ISSUES ENRRA Side :  Stress in operator licensing examinations on the bases and response to severe accident,  Prepare an inspection plan of the safety systems of the two reactors, and others nuclear facilities,  Arrange seminars of Fukushima accident,  Shares in national and international meeting and workshops dealing with Fukushima accident,  Carry out its duties as the organizer of "The national committee of nuclear and radiation emergency", incase of accident,

29 August 2013 40 Nuclear and radiological REFERENCES Regulatory Authority Egypt - ENRRA

1. IAEA, "Fundamental Safety Principles", SSS , Safety Fundamentals, No. SF-1, 2006, 2. IAEA, "Basic Safety Principles for Nuclear Power Plant", INSAG 12, supersedes INSAG No. 75-INSAG-3 rev1,Vienna, 1999; 3. IAEA, "Safety of NPP design and construction", SSS , Specific safety requirements, SSR 2/1, Vienna 2012, 4. IAEA, "Safety of NPP operation and commissioning", SSS specific safety requirements, SSR 2/2, Vienna 2011, 5. IAEA, "Deterministic Safety Analysis for NPP", SSS , Specific safety guide, SSG-2, Vienna 2009, 6. IAEA, "Periodic Safety Review for NPP", SSS , Specific safety guide, SSG-25, Vienna 2013, 7. IAEA, "defence in depth in nuclear safety", INSAG 10, Vienna, 1996, 8. IAEA, "Nuclear safety infrastructures for national nuclear power program" INSAG 22, Vienna, 2008. 9. IAEA, "Establishing the safety infrastructures for nuclear power program", SSS, Specific safety guides, SSG-16, Vienna,

29 August 2013 41 Nuclear and radiological Regulatory Authority Egypt - ENRRA THANK YOU FOR YOUR ATTENTION

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