Cernavoda, Iunie 2011 OVERVIEW ON PERFORMANCE & PERSPECTIVE IONEL BUCUR, Ph.D. CERNAVODA NPP SITE DIRECTOR & SNN SA CNO JUNE 2011 NUCLEARELECTRICA S.A

Cernavoda, Iunie 2011

OVERVIEWON PERFORMANCE &

PERSPECTIVE

IONEL BUCUR, Ph.D.CERNAVODA NPP SITE DIRECTOR

& SNN SA CNO

JUNE 2011

NUCLEARELECTRICA S.A.


NUCLEARELECTRICA

NUCLEARELECTRICA HEADQUARTERS

CNE CERNAVODA BRANCH

FCN PITESTI BRANCH


OUR MISSION

CNE CERNAVODA

TO PRODUCE “CLEAN” ELECTRICAL AND THERMAL POWER IN RESPECT OF NUCLEAR SAFETY CONDITIONS AND ECONOMICAL EFFICIENCY;

TO CONSTANTLY TRANSFORM THE WORKING ENVIRONMENT SUCH AS THE PLANT PERSONNEL FEEL THE PRIDE AND THE PRIVILEGE TO BE PART OF CERNAVODA NPP.


OUR VISION

CERNAVODA NPP – A PLANT AMONG THE FIRST 25 NUCLEAR POWER PLANT IN THE WORLD BY THE END OF 2013;

MEET ALL REQUIREMENTS & CONDITIONS IMPOSED BY EUROPEAN COMMUNITY FOR NUCLEAR INDUSTRY;

MANAGEMENT OF RADIOACTIVE WASTE AND DECOMMISIONIG ACCORDING TO LEGAL PROVISIONS AND EUROPEAN PRACTICES;

BE INVOLVED IN U3 & U4 COMPLETION & OPERATION;

SUPPORT THE DEVELOPMENT OF LOCAL COMMUNITY AND MAINTAIN A PERMANENT DIALOGUE WITH LOCAL COMMUNITY IN ORDER TO INCREASE THE ACCEPTANCE OF NUCLEAR ENERGY;


PLANT PERFORMANCE PRODUCTION OF ELECTRICAL POWER DELIVERED TO THE NATIONAL GRID U1&U2 (MWh)

SINCE COMMERCIAL PRODUCED DELIVERED U1 79508542 73369583 U2 20687243 19080491 Total 100195785 92450074

0

1000000

2000000

3000000

4000000

5000000

6000000

Produced U1 5400856 5307181 5198083 5455751 5445900 5513410 4905663 5548082 5554959 5631510 6005176 5227976 6158677 5622273 2533045

Deliv ered U1 4968837 4918951 4813027 5053355 5049871 5106225 4541418 5142305 5114677 5177957 5518346 4805476 5661617 5167231 2330290

Produced U2 961986 5997832 5593082 6001219 2133124

Deliv ered U2 887240 5528108 5158248 5537520 1969375

Produced U1+U2 11623492

Deliv ered U1+U2 10704751

1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 20105 months

2011


ELECTRICAL POWER PRODUCTION IN 2010 – BREAKDOWN BY RESOURCE TYPE

19.4

35.710.20.9

33.8

Nuclear Hydro Gas Oil Coal


GROSS CAPACITY FACTOR U1&U2 (%)

0

20

40

60

80

100

GCF U1 87,27 86,19 84,51 88,30 88,25 89,37 79,52 89,71 90,08 91,37 97,62 84,83 100,10 91,53 99,82

GCF U2 93,12 96,92 90,62 97,24 84,13

1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 20105

months 2011


COMPARED WITH OTHER SIMILAR CANDU UNITS, THE CAPACITY FACTOR SIS, AT THE END OF MARCH 2011 WAS:

SINCE IN SERVICE

1. CERNAVODA 2 95,3%2. WOLSONG 3 94,9%3. WOLSONG 4 94,9%4. WOLSONG 2 93,8%5. QINSHAN 5 91,3%6. QINSHAN 4 90.2%

7. CERNAVODA 1 89,4%8. DARLINGTON 3 86.3%9. DARLINGTON 4 85,7%10. EMBALSE 84,9%……………………………………………………………………………………..

AT THE END OF MARCH 2011, CERNAVODA 1 WAS SITUATED ON 7TH PLACE SIS OUT OF 27 PHWR OPERATING UNITS AND UNIT 2 ON 1ST PLACE SIS.


IMPACT ON PEOPLE & ENVIRONMENT CUMMULATED RELEASES OF RADIOACTIVE EFFLUENTS U1&U2 (μ Sv)

LEGAL DOSE FOR POPULATION 1000 Sv AUTHORISATION CONSTRAINT 100 Sv THE AVERAGE ANNUAL DOSE 0,57% FROM THE LEGAL DOSE (14 YEAR ROLLING)

0

2

4

6

8

10

12

14

Radioactive eff luents U1 5,51 5,68 4,49 7,22 7,27 8,3 6,11 9,94 8,18 13,27 10,45 4,82 7,07 3,98 0,90

Radioactive eff luents U2 0,15 0,88 1,44 1,75 0,54

Total 10,6 5,7 8,51 5,73 1,44

1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 20105

months 2011


VOLUME OF RADIOACTIVE WASTE U1&U2 (mm33) TOTAL: 429.55

AVERAGE ANNUAL DESIGN VALUE: 30 m3/ unit

0

10

20

30

40

50

60

Radioactive Waste U1 11,86 16,28 21,35 16,54 24,22 29,39 26,41 29,78 28,47 25,76 24,06 44,47 21,4 31,52 14,12

Radioactive Waste U2 10,86 19,43 18,32 15,31

Total 55,33 40,83 49,84 29,43

1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 20105

months 2011


COLLECTIVE RADIATION EXPOSURE U1&U2 (man·mSv/ unit)

0

200

400

600

800

1000

1200

1400

1600

1800

2000

Cernav oda NPP 248,3 257,6 456,5 466,2 574,8 550,5 818,3 656,7 731,6 561,1 278,8 344,5 242,5 395 130

CANDU-6 mean v alue 1317 1324 1508 1530 1130 1734 1882 1122 1368 674 1058 1816

1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 20105 months

2011


INTERNATIONAL COOPERATION

In 2007 – 2011 CERNAVODA NPP PARTICIPATED ACTIVELY IN OUTSIDE ORGANIZATION MISSIONS, PROVIDING EXPERTS FOR:

5 OSART MISSIONS ORGANIZED BY IAEA IN BELGIUM, GERMANY, JAPAN, SWEDEN, AND CZECH REPUBLIC;

17 WANO PEER REVIEWS AT CANADIAN (2 – BRUCE, GENTILLY, 2 - DARLINGTON), SPAIN (TRILLO) AND USA (THREE MILES ISLAND, CATAWBA, PALISADES, COOPER, RIVER BEND, SEEBROOK, DIABLO CANYON, SEQUOYAH, AND BRUNSWICK) NUCLEAR POWER PLANTS.

THE SMOOTH TRANSFER OF KNOWLEDGE AND EXPERIENCE BETWEEN TEAM MEMBERS AND STAFF OF THE EVALUATED PLANT IS ENSURED FOLLOWING THESE MISSIONS, ALLOWING EACH PERSON TO LEARN FROM THE EXPERIENCE OF THE OTHERS AND TO ALIGN TO THE BEST INTERNATIONAL PRACTICE IN THE FIELD. THE FINAL GOAL IS TO OBTAIN A SAFE AND RELIABLE OPERATION OF THE NUCLEAR POWER PLANTS.


MAJOR OBJECTIVES FOR 2011

PLANT GROSS CAPACITY FACTOR 95% (CONTINUOUS OPERATION BETWEEN

PLANNED OUTAGES);

NUMBER OF REPORTABLE EVENTS 8;

DECREASE OF INTERNAL DOSE WEIGHT IN THE TOTAL DOSE (20%);

CONSOLIDATION OF THE ORGANIZATION & LEADERSHIP (“ALL THAT IS GOOD”);

EFFICIENT UTILIZATION OF HUMAN RESOURCES AND OPTIMIZATION OF THE

NUMBER OF EMPLOYEES IN THE ORGANIZATION;

OPTIMIZATION OF O&M COSTS & WAREHOUSE STOCKS;

SUCCESSFULLY PASS THE “STRESS TESTS”.


WANO PEER REVIEW – NOVEMBER 2010

PERFORMANCE HAS IMPROVED IN MANY AREAS BECAUSE OF STATION

LEADERSHIP PROVIDING CLEAR VISION AND DIRECTION;

IDENTIFIED PROBLEMS ARE SYSTEMATICALLY RESOLVED AND IN SEVERAL

CASES PREVIOUS WEAKNESSES HAVE BECOME AREAS WORTHY OF INDUSTRY

EMULATION;

THE NUCLEAR AND INDUSTRIAL SAFETY CULTURES ARE HEALTHY;

THE WORKFORCE CLEARLY UNDERSTANDS THAT NUCLEAR SAFETY TAKES

PRIORITY OVER PRODUCTION AND HAS DEMONSTRATED AN EXEMPLARY

INDUSTRIAL SAFETY ACCIDENT RATE OVER THE REVIEW PERIOD;

.EQUIPMENT PERFORMANCE AND A CULTURE INTOLERANT OF EQUIPMENT

FAILURES HAVE IMPROVED OVER THE REVIEW PERIOD.


PROVIDE AROUND 1675 JOBS AS SNN EMPLOYEES AND, ON THE LONG TERM, AROUND

800 JOBS FOR CONTRACTOR COMPANIES;

PROVIDE HEATING FOR MORE THAN 60% OF CERNAVODA HABITANTS (APPROX. 50000

Gcal/2010) AT THE LOWEST PRICE IN THE COUNTRY;

PROVIDE A CONSTANT INCOME TO THE LOCAL BUDGET, WHICH CONTINUOUSLY

INCREASED. ONLY IN 2010 A TOTAL AMOUNT OF 12,9 MIL LEI REPRESENTING TAXES,

DUTIES, AND OTHER OBLIGATION WERE PAID;

MORE THAN 600 LODGINGS WERE PROVIDED TO ACCOMMODATE 725 EMPLOYEES;

SOCIAL & ECONOMICAL EFFECTS

STARTING 1992 AN IMPORTANT PROGRAM IS BEING DEVELOPED “EMERGENCY SOCIAL

PROGRAM FOR IMPROVING LIFE CONDITIONS IN CERNAVODA”;


11 MAJOR PROJECTS WERE FINALIZED AT THE END OF 2010, IN AMOUNT OF 50 MILLION EURO:

MINIMARKET (“FOISOR”);

KINDERGARTEN;

DOMESTIC WATER STATION (PUMPING & TREATMENT);

ROAD CONNECTIONS AND FIRST TRAFFIC LIGHTS IN INTERSECTIONS;

HEATING SYSTEM AND THERMAL STATIONS; “ST. MARIA” BRIDGE WHICH ASSURES ROAD ACCESS TO CERNAVODA RAILWAY STATION AND TO FETESTI – CERNAVODA HIGHWAY;

THEORETICAL HIGHSCHOOLS;

HOSPITAL WITH 100 BEDS AND DISPENSARY;

SEWAGE TREATMENT PLANT;

A POTABLE WATER WELL.

PRESENTLY TWO PROJECTS ARE ON GOING:

YOUTH RECREATION CENTER;

EXTENSION OF HEATING SYSTEM FOR CERNAVODA TOWN.


FURTHER SUPPORT WAS PROVIDED TO LOCAL COMMUNITY FOR PEOPLE AFFECTED BY JULY 2010 FLOODS:

WATER DISCHARGE AND SLUDGE CLEANING FROM THE STREETS;

BUILDING AND EQUIPPING A COMPLEX OF TEMPORARY LODGINGS (588064 LEI);

CLOTHING AND BEDDING (36119 LEI).

BEDDING THE BOARDING OF CERNAVODA HIGH SCHOOL (29514 LEI).


Cernavoda NPP Units 3&4 ProjectMotivation/Necessity/Opportunity of the Project

THE MAIN CHALLENGES FOR THE NATIONAL ENERGY SYSTEM ARE THE INCREASE OF DEMAND, THE REPLACEMENT OF NONPERFORMANT AND OUTDATED CAPACITIES, THE INTEGRATION OF AN INCREASING LARGER QUANTITY OF RENEWABLE ENERGY, THE SECURITY OF SUPPLY AND THE POSITIONING ON THE EUROPEAN REGIONAL MARKET.

ROMANIA’S ENERGY STRATEGY FOR THE PERIOD 2011-2035 – OBJECTIVES :– ENERGY SAFETY– COMPETITIVENESS ON THE INTERNAL AND REGIONAL MARKET– SUSTAINABLE DEVELOPMENT – ENVIRONMENT PROTECTION AND CLIMATE CHANGE CONTROL– NECESSARY CAPITAL FOR MODERNIZATION AND SECTOR DEVELOPMENT– THE FURHTER DEVELOPMENT OF A COMPETITIONAL MARKET CHARACTERIZED BY

COMPETITION, TRANSPARENCY AND LIQUIDITY

CERNAVODA NPP UNITS 3&4 REPRESENT A PART OF THE FORESEEN ENERGY MIX AND ENSURE ANNUAL SUPPLEMENTARY ENERGY QUANTITY OF 11 TWH INTO THE NATIONAL ENERGY SYSTEM


Cernavoda NPP Units 3&4 Project Project objective

Calandria Vassel

Pressure tubes

Fuelling machine

• PRODUCTION CAPACITY 2X720 MWE• ANNUAL ENERGY OUTPUT 11 TWH• CANDU TYPE REACTORS,

– NATURAL URANIUM AS FUEL– HEAVY WATER AS MODERATOR AND

COOLING AGENT

• USE OF NATIONAL INFRASTRUCTURE –EXISTING CAPACITIES FOR NUCLEAR FUEL MANUFACTURING AND HEAVY WATER–OPERATION EXPERIENCE OF UNITS 1 & 2–ENGINEERING KNOWLEDGE OF DESIGN ORGANIZATIONS–ENTREPRENEURIAL EXPERIENCE–AVAILABILITY IN THE MANUFACTURING OF EQUIPMENTS AND MATERIALS–EXPERTISE OF THE REGULATORY BODY–CAPITALIZATION OF SITE AND EXISTING CONSTRUCTIONS


Cernavoda NPP Units 3&4 ProjectProject responsibility

• S.C. ENERGONUCLEAR S.A. – ESTABLISHED BY GD 1565/2008 AS A JOINT STOCK COMPANY REGISTERED IN ROMANIA

IN COMPLIANCE WITH THE LAW OF COMMERCIAL COMPANIES (LAW 31/1990) – HAVING THE OBJECTIVE TO DEVELOP, CONSTRUCT AND OPERATE CERNAVODA NPP

UNITS 3&4• ADDITIONAL ACT NR.3 TO THE INVESTORS AGREEMENT – SHAREHOLDING STRUCTURE OF

S.C. ENERGONUCLEAR S.A– ARCELORMITTAL GALATI S.A.,– ENEL INVESTMENT HOLDING B.V. – S.N. NUCLEARELECTRICA S.A.

• PROJECT DEVELOPMENT IN 2 PHASES – PRE-PROJECT AND PROJECT• PRE-PROJECT PHASE – PREPARATORY ACTIVITIES UP TO INVESTMENT DECISION MAKING

– SELECTION OF THE MAIN CONTRACTOR (EPC)– DRAFTING OF NUCLEAR SAFETY AND AUTHORIZATION RELATED DOCUMENTATION– ESTABLISHMENT OF THE ECONOMICAL AND FINANCIAL MODEL, PROJECT FEASIBILITY

ASSESSMENT, IDENTIFICATION OF FINANCIAL RESOURCES– CONTRACT DRAFTING FOR THE OPERATION AND MAINTENANCE OF THE GROUPS,

HEAVY WATER AND NUCLEAR FUEL SUPPLY THROUGHOUT OPERATION PERIOD. – DRAFTING OF AGREEMENTS FOR ENERGY OFF-TAKE


Cernavoda NPP Units 3&4 ProjectEstimated value

• THE PROJECT IS ESTIMATED AT 4 BILLION EUROS (ESTIMATIONS DONE IN 2008);

• WITHIN THE SELECTION PROCEDURE OF THE MAIN CONTRACTOR, THERE ARE SEVERAL PHASES:

– QUALIFICATION OF BIDDERS – NEGOTIATION OF PRELIMINARY BIDS– NEGOTIATION OF FINAL OFFERS AND CONTRACT AWARDING

THE INVESTMENT COSTS WILL BE DETERMINED BASED ON THE PRELIMINARY OFFERS RECEIVED FORM POTENTIAL CONTRACTORS.


Cernavoda NPP Units 3&4 ProjectFinancing resources

• FINANCIAL CONSULTANT – FINANCING STRUCTURE

– INTERNAL RESOURCES AND LOANS OF THE SHAREHOLDERS

– “PROJECT FINANCING” LOAN TYPE

– SHAREHOLDERS’ GUARANTIES


Cernavoda NPP Units 3&4 ProjectCurrent status

•APPROVAL OF THE PROJECT BY THE EUROPEAN COMMISSION;

•COMPLETION OF EXISTING BUILDING INSPECTION AND CONFIRMATION BY AECL OF THE CONFORMITY WITH THE FUNCTIONS THET THEY WERE INITIALLY DESIGNED FOR.

•DEFINING OF HIGHER AUTHORIZATION STANDARDS–TARGET VALUES FOR NUCLEAR SAFETY–SIZING OF STRUCTURES AND EQUIPMENTS IN CASE OF EARTHQUAKE

•PROJECT DEFINITION – IDENTIFICATION AT CONCEPT LEVEL OF PROJECT IMPROVEMENTS

AND MODIFICATIONS.


CERNAVODA NPP SAFETY READINESS

- FUKUSHIMA PERSPECTIVE -


FUKUSHIMA DAIICHI UNIT 1 - PRELIMINARY REMARKS

TYPICAL BWR 3 AND 4 REACTOR DESIGN TYPICAL BWR 3 AND 4 REACTOR DESIGN



AFFECTED BWR UNITS WERE BROUGHT INTO SERVICE IN THE EARLY

1970’s, BEFORE MORE RECENT CHANGES WERE INTRODUCED IN NPP

SAFETY REQUIREMENTS;

LIMITED CONTAINMENT VOLUME WHICH ENABLE HYDROGEN TO REACH

QUICKLY A RELATIVELY HIGH CONCENTRATION;

A RELATIVELY SMALL RESERVE OF WATER IN AND AROUND REACTOR

CORE;


INTERIM SPENT FUEL BAY LOCATED MUCH HIGHER THAN GROUND LEVEL;

THE FUKUSHIMA EVENT WAS INITIATED BY AN EARTHQUAKE & TSUNAMI, BOTH BEYOND DESIGN BASIS;

THE EVENT CONSEQUENCES (DAMAGE OF THE NUCLEAR FUEL RESULTED IN RADIOLOGICAL RELEASES) WERE DUE TO A COMBINATION OF A SEVERE COMBINED EXTERNAL EVENT AND THE PARTICULAR CHARACTERISTICS OF THE NUCLEAR PLANT DESIGN.


CERNAVODA NPP CANDU 6 SAFETY READINESS OVERVIEW

KEY BACKGROUND POINTS:

CANDU 6 REACTORS HAVE TWO SEPARATE, REDUNDANT FAIL-SAFE SHUTDOWN

SYSTEMS, (ONE SEISMICALLY QUALIFIED) WHICH WILL SHUT THE REACTOR DOWN IN

ANY SEISMIC EVENT THAT CAUSES OPERATING PARAMETERS TO DEVIATE

(SECONDARY CONTROL ROOM SEISMICALLY QUALIFIED);

LARGE VOLUME OF COOLING WATER IS CONTAINED IN THE DOUGING TANK OF THE

REACTOR BUILDING (APPROX. 3000 Mg) READY TO SUPPRES THE PRESURE OR TO

COOL BY GRAVITY THE REACTOR CORE;

THE CANDU 6 REACTOR CORE INCLUDES A LARGE VOLUME OF LOW-TEMPERATURE,

LOW PRESSURE MODERATOR WATER (APPROX 260Mg) WHICH PROVIDES AN

INHERENT BACKUP HEAT SINK. THE LARGE THERMAL CAPACITY OF THIS WATER,

AND THE SURROUNDING SHIELDING VAULT WATER (APPROX 600Mg), PROVIDES AN

INTERIM HEAT SINK, WITH PASSIVE CAPABILITY FOR MANY HOURS;


CANDU 6 UNITS HAVE A LARGE CONTAINMENT BUILDING (IN COMPARISON TO

THE FUKUSHIMA UNITS) WHICH LIMITS THE IMPACT OF STEAM DISCHARGE OR

HYDROGEN RELEASE INTO CONTAINMENT. OVERALL HYDROGEN

CONCENTRATIONS ARE LOW, AND HYDROGEN IS MIXED IN CONTAINMENT BY

ACTION OF LOCAL AIR COOLERS AND ALSO BY NATURAL CONVECTION.

MITIGATION SYSTEMS (IGNITERS OR RECOMBINERS) ARE DEPLOYED TO

MANAGE HYDROGEN FOR CANDU 6;

CERNAVODA NPP CANDU 6 UNITS ARE DESIGNED FOR APPROPRIATE SEISMIC

CONDITIONS BASED ON THE CHARACTERISTICS OF CERNAVODA SITE.


CONTAINMENT SYSTEM


BASIC BLUEPRINT OF CANDU 6 UNIT


SHUTDOWN SYSTEMS 1 & 2


EMERGENCY CORE COOLING SYSTEM


ROBUSTNESS TO DESIGN-BASIS AND BEYOND-DESIGN-BASIS EARTHQUAKES

CERNAVODA NPP CANDU 6 UNITS, LIKE OTHER NUCLEAR PLANTS, ARE DESIGNED TO

WITHSTAND EARTHQUAKES BASED ON A “DESIGN BASIS EARTHQUAKE” GROUND

MOTION FOR THE CERNAVODA SITE CHARACTERISTICS;

BASED ON APPROVED STUDIES DEVELOPED BY THE ROMANIAN CENTER FOR EARTH

PHYSICS THAT TOOK INTO ACCOUNT THE CONSERVATIVE HISTORY OF THE ENTIRE

REGION, INCLUDING THE CLOSEST SEISMIC AREAS, VRANCEA AND SHABLA (BALKAN

MOUNTAINS), CERNAVODA NPP WAS DESIGNED TO RESIST EFFECTS OF EARTHQUAKES.

THE ABOVE-MENTIONED STUDIES HAVE SHOWN THAT, HISTORICALLY, THE TWO

OUTBREAKS LOCATED AT OVER 100KM FROM SITE NEVER HELD AN EARTHQUAKE

GREATER THAN 7.5 DEGREES. IN THIS CONTEXT, CERNAVODA NPP PROJECT

CONSERVATIVELY CONSIDERED A MAXIMUM POSSIBLE EARTHQUAKE OF MORE THAN 8

DEGREES;

THE INITIAL PROJECT, WHICH CONSIDERED A DESIGN BASIS EARTHQUAKE THAT MIGHT

OCCUR EVERY MORE THAN 1000 YEARS AND MIGHT PRODUCE A MAXIMUM PEAK

ACCELERATION OF 0.2G AT GROUND LEVEL, WAS CONFIRMED BY SUBSEQUENT STUDIES

AUDITED BY IAEA EXPERTS.

THESE STUDIES HAVE EXAMINED IN DETAIL THE PLANT RESPONSE CONCLUDING THAT

THERE ARE SIGNIFICANT DESIGN MARGINS (>0.35G) FOR SEISMIC EVENTS BEYOND THE

DESIGN BASIS, AN EARTHQUAKE THAT MIGHT OCCUR EVERY 10.000 YEARS.


SEISMIC CAPACITY AFTER SEISMIC FRAGILITY ANALYSIS FOR THE NUCLEAR BUILDINGS AND GENERATORS

NO. SUBJECT MAXIMUM GROUND

ACCELERATION

DESIGN GROUND

ACCELERATION

RECCURENCE PERIOD (YEARS)

1 R/B – internal structures 0.45g 0.204g >1/10000

2 R/B – containment wall 0.45g 0.204g >1/10000

3 S/B - block walls 0.35g 0.204g >1/10000

4 T/B 0.30g 0.204g >1/10000

5 D2O-Tower, EPS/SCR, HPECC, EWS

>0.45g 0.204g >1/10000

6 Pump House 0.30g 0.204g >1/10000

7 StandBy Diesels 0.45g 0.204 >1/10000

8 Generators 3.20g 0.204g >1/10000

Nota: PGA value for a recurrence period of 1/10000 years is 0.291g according to preliminary results Rizzo & Associates studies. PGA value for current DBE (period of 1/1000 years) is 0.204g.


BEYOND DESIGN-BASIS FLOODING

CERNAVODA NPP CANDU 6 PLANT IS ASSESSED FOR ITS CAPABILITY TO

WITHSTAND BOTH INTERNALLY-CAUSED (e.g. PIPING RUPTURE) OR EXTERNALLY-

CAUSED FLOODS;

ANY EXTERNALLY-CAUSED FLOOD WOULD NOT AFFECT THE SYSTEMS AND

STRUCTURES INSIDE THE CONTAINMENT, WHICH IS DESIGNED TO BE SEALED

OFF FROM THE OUTSIDE;

THE REALITY SHOWS THAT CERNAVODA NPP SITE IS LOCATED AT 15.8M ABOVE

THE BLACK SEA LEVEL AND 2M ABOVE THE MAXIMUM POSSIBLE LEVEL OF

DANUBE WATERS, WHICH MAY OCCUR IN 10,000 YEARS;

THE DRAINAGE SYSTEMS OF CERNAVODA NPP SITE CAN ACCOMMODATE MORE

THAN 100l/ h/ m2 AND IS SURROUNDED BY A WATER COLLECTION NETWORK

DESIGNED TO WITHSTAND A SEVERE QUICK RAINFALL. IN ROMANIA, THE MORE

SEVERE QUICK RAINFALL THAT CAUSED EXTREME FLOODS HAS NEVER

EXCEEDED 75l/ h/ m2.


RESPONSE TO PROLONGED STATION BLACKOUT

AFTER THE REACTOR IS SHUTDOWN, BY DESIGN, CERNAVODA NPP CANDU 6

HAS A NUMBER OF SYSTEMS TO REMOVE DECAY HEAT, SUCH AS THE

FEEDWATER SYSTEM, SHUTDOWN COOLING SYSTEM, MODERATOR SYSTEM AND

EMERGENCY WATER SUPPLY;

FEEDWATER SHUTDOWN COOLING AND MODERATOR SYSTEMS OPERATE

UNDER CLASS IV AND CLASS III POWER (INDEPENDENT DIESEL GENERATORS);

IF CLASS IV AND CLASS III POWER ARE UNAVAILABLE, SEISMICALLY QUALIFIED

EPS WILL BE STARTED. IN THIS CASE, PUMPED EMERGENCY WATER SUPPLY

(EWS) OPERATING UNDER EPS CAN ENSURE LONG TERM FUEL COOLING;

FOLLOWING TOTAL LOSS OF OFF-SITE AND ON-SITE POWER, THE STEAM

GENERATOR HEAT SINK IS MAINTAINED BY MAKE-UP TO STEAM GENERATORS BY

GRAVITY FROM THE DOUDING TANK, AFTER STEAM GENERATOR RAPID

COOLDOWN.


ABILITY TO RESTORE AND MAINTAIN LONG TERM COOLING TO CORE

AS NOTED ABOVE, EVEN IN THE ABSENCE OF ALL ELECTRICAL POWER, NATURAL

CIRCULATION FLOW IN THE HEAT TRANSPORT SYSTEM COUPLED WITH PASSIVE

GRAVITY-FED SUPPLY OF WATER TO THE STEAM GENERATORS, PROVIDES COOLING FOR

SEVERAL DAYS;

IN THE LONGER TERM, ARRANGEMENTS CAN BE MADE TO REPLENISH WATER IN THE

DOUSING TANK VIA EITHER THE FIREWATER SYSTEM OR WATER TANKER TRUCKS;

BY DESIGN, THE CANDU 6 CORE IS SUBDIVIDED INTO FUEL CHANNELS, EACH

SURROUNDED BY LOW-PRESSURE, LOW-TEMPERATURE MODERATOR HEAVY WATER.

THIS MEANS THAT, OVERALL THERE IS A RELATIVELY LARGE AMOUNT OF WATER

AVAILABLE FOR EMERGENCY FUEL COOLING;


ABILITY TO RESTORE AND MAINTAIN LONG TERM COOLING TO CORE (CON’T)

THE LARGE QUANTITIES OF WATER IN THE MODERATOR AND SHIELD TANK MEAN THAT,

EVEN IN THE PROLONGED ABSENCE OF ELECTRIC POWER, AND ASSUMING THE FAILURE

OF NATURAL CIRCULATION COOLING, MANY HOURS OF TIME WOULD ELAPSE BEFORE

THE WATER NEEDS TO BE REPLENISHED;

IN ADDITION, TWO VERY IMPORTANT FEATURES HAVE BEEN PROVIDED:

TWO WATER WELLS HAVE BEEN DRILLED FOR PROVIDING COOLING WATER, WITH

A CAPACITY OF 190m³/h;

TWO MOBILE DIESEL GENERATORS HAVE BEEN BROUGHT ON SITE AS OUTSIDE

ALTERNATIVE ELECTRICAL SOURCE FOR EWS & SCR.


ROBUSTNESS OF SPENT FUEL MANAGEMENT SYSTEMS

THE RISK OF FUEL UNCOVERING AND OVERHEATING IN CANDU 6 SPENT FUEL

BAYS (SFB) IS EXTREMELY LOW DUE TO THE REDUNDANT POWER SUPPLY

OPTIONS, THE MODEST FUEL HEAT LOAD, AND THE LARGE INVENTORY OF

WATER WHICH ENSURES A LONG PERIOD OF TIME AVAILABLE TO RESTORE

COOLING;

THE SFBs ARE REINFORCED CONCRETE VESSELS LOCATED BELOW GRADE

LEVEL. THE BAYS ARE DESIGNED TO WITHSTAND A DESIGN BASIS EARTHQUAKE

(DBE);

ASSESSMENTS HAVE SHOWN THAT THERE IS SUFFICIENT SEISMIC MARGIN IN

THE SFB DESIGN TO SURVIVE AN EARTHQUAKE GREATER THAN THE DBE

WITHOUT THE WALL RUPTURING;

THE PIPING LAYOUT FOR THE BAY COOLING SYSTEM IS DESIGNED TO PROHIBIT

DRAINING OF THE BAY IN THE EVENT OF A PIPE RUPTURE;

DECAY HEAT FROM THE SPENT FUEL IN THE SFB IS REMOVED BY RE-

CIRCULATING THE BAY WATER THROUGH A HEAT EXCHANGER, WITH PUMPS

POWERED BY OFF-SITE CLASS IV AND BACKUP CLASS III POWER;


ROBUSTNESS OF SPENT FUEL MANAGEMENT SYSTEMS (CON’T)

CERNAVODA NPP CANDU 6 NATURAL URANIUM FUEL BUNDLES ARE GRADUALLY

DISCHARGED DURING REACTOR OPERATION AND ARE STORED IN THE BAY FOR

ABOUT 6 YEARS BEFORE THEY CAN BE MOVED TO PASSIVE AIR-COOLED DRY

STORAGE (WHICH DOES NOT NEED ANY EXTERNAL SOURCE OF POWER OR

OTHER SERVICES);

ALTERNATIVE METHODS TO COOL THE SPENT FUEL BAY ARE AVAILABLE FROM

FIREWATER OR AN EXTERNAL SOURCE (WELL WATER & FIRE TRUCK);

EVEN IN THE CASE IN WHICH THE MAXIMUM FUEL LOAD IS IN THE BAY AND THE

COOLING CIRCUIT IS NOT AVAILABLE DUE TO LOSS OF ALL AVAILABLE POWER

SUPPLIES, IT WOULD TAKE APPROXIMATELY 13 DAYS BEFORE THE TOP ROW OF

THE FUEL BUNDLES BECOME UNCOVERED, AND EVEN LONGER BEFORE ANY

SIGNIFICANT FUEL OVERHEATING OCCURS;



Documents

Cernavoda, Iunie 2011 OVERVIEW ON PERFORMANCE & PERSPECTIVE IONEL BUCUR, Ph.D. CERNAVODA NPP SITE DIRECTOR & SNN SA CNO JUNE 2011 NUCLEARELECTRICA S.A