РОССИЙСКАЯ АКАДЕМИЯ НАУКИнститут проблем безопасного развития атомной энергетики

RUSSIAN ACADEMY OF SCIENCES
Nuclear Safety Institute (IBRAE)

Russia’s efforts to improve safety following
Russia’s
the Chernobyl and the Fukushima accidents
Leonid Bolshov

Post Chernobyl efforts
SU/Russia changed attitude to SA:
 Science based approach Internationalization
 Studies of DiD phenomena and models
 Scenario analysis
 Harmonization of regulations (INSAG-3)
 Modernization of all NPPs
 Upgrade of the Russian emergency response
system and Rosatom emergency system2

Basic Safety Principles

LEGISLATIVE BLOCK

SAFETY CULTUREPriority ranking
Human factor

Federal laws
(principles ofresponsibilities)
System of norms
and regulations
Availability ofstate licensing
system(independentregulation)

3

TECHNOLOGICAL
BLOCK(Technicalprovision of safety)

PRINCIPLE OF
DEFENSE-IN-DEPTH

BASE ofKNOWLEDGE
about processes
andphenomena

Multiple safetybarriers
Diverse levels ofsafety barriers
accidents to beprevented
mitigation of accident
consequences(emergencymanagement)Reactivity accidents

variousvarious types
types ofof fuelfuel rodrod destructions
destructions

CLAD BREACH
Clad cogging overfuel pellet boundary

Fuel rod withhigh burn-up (left)
and with fresh
fuel (right)

FUEL ROD FRAGMENTATION

Lower plugwith sow melt

Cross-section offuel rod withmaximal
deformation
Specific swellingwith clad breach
Fuel pellet fragments withmelted-out central cavity

4Loss of coolant accidents
RASPLAVIn vessel melt retention
 Database on thermal physical properties of corium
contains data for temperatures up to 3100 К Database of crucial parameters describing themolten pool behavior was created A tool for analysis was developed

5MASCAChange of Russian Safety Concept (INSAG-3)
 OLD SAFETY CONCEPT

6

 NEW SAFETY CONCEPT

1. In-depth analysis: designbasis accidents andpostulated initiating events

1. Analysis of beyond-designbasis accidents withpossible severe damage ofreactor core up to its fullmelting

2. Number of registeredfailures during evolution ofdesign-basis accidents islimited to the principle of asingle failure

2. A principle of a single
failure is withdrawn while
analyzing the beyonddesign-basis accidents

Development of safety requirements Toughening the requirement of various defense levels
independence, minimization of possibility of accident
development at next stages
 Radiation risk in all conditions and modes should becomparable with the risk from other industrial
installations used for similar purposes There should not be a necessity in evacuation out of theplant site
 Requirements on placing the nuclear installations
should not contain additional restrictions in comparison
with other industrial facilities

7

Post Chernobyl efforts

Adoption of safety culture principles: Priority of safety in design, construction andoperation in general and day-to-day management
 Education and training programs
 Full scope simulators at every plant

8Post Chernobyl efforts

Cleaning and remediation
 Cleaning of contaminated areas after Chernobyl
 Medical screening
 1990 Extraordinary protection measures 1994 Conversion of federal programs from saving
lives to social rehabilitation

9

Efficiency
Efficiency ofof water
water protection
protection measures
measures at
at thetheChernobyl
Chernobyl NPP
NPP andand their
their environmental
environmental effects
effects

Cost,
Localized
106
Countermeasure l37Cs activity,
TBq
dollars

Individuals

Specific cost,dollars/MBq

Environmental
effects

Filtering damsystem

3000

420-620

Forest flood in 4000 hc

0.074-0.11

46

Wells inriverbed

0.44-0.7450

50068-114Pond-cooler
isolation< 0.037> 100> 1000

> 27004.5 mln. m3 sandcapture, which sandcould cover ooze
sediments in Kiev
reservoir
Elevation of groundwaters in the Chernobyl
NPP siteComparative
Comparative efficiency
efficiency ofof protective
protective measures
measuresrelatedrelated toto reduction
reduction ofof radiation
radiation exposure
exposureCostsCosts ofof countermeasurescountermeasures after
after thethe Chernobyl
Chernobyl NPP
NPP
accident
accident

Range of reduced costs,Experience (year, place,dollars per 1 man Sv, man Gy
contingent)
Iodine prophylaxis
0.02-0.1
1986, Pripyt population
Sanitary treatment
25-5001986, Chernobyl NPP area
1986 Children of
One week refusal of milk
contaminated areas of the1-15
consumption (children)
UkraineRestriction of consumption
2,800-25,000
1986, Bryansk region
and control of local
8,600-68,000
1987, Bryansk region
foodstuff
13,800-120,000
1989, Bryansk region
CountermeasureChernobyl experience
Contamination density Average dose, mSvArea, km2Population, thous.

> 15 Ci/km2(555 kBq/m2)

101100085> 40 Ci/km2(1480 kBq/m2)

4036207

In accord with the “Chernobyl Law” in 1991, the territories contaminated with Cs
above 1 Ci/km2 were assigned with the affected lands. The total area comprised
160 thous. km2 with the population of about 3 million.
As the Chernobyl experience showed, the excessive and radiologically unjustified
protective measures (primarily evacuation) could lead to a sharp amplification ofnegative psychological, social and economic consequences.

Legacy issues
During restructuring of economy after SU
disintegration, a number of back-end and legacy
issues are being solved:
 Since 2008, a large-scale Federal Program
addressing legacy and back-end issues is inprogress Safety of waste and SNF storage improved Centralized dry storage of SNF built
 2011 Federal Law on Radioactive Waste
Management had set a limit for temporary storageand necessitated ultimate disposal of all wastes

14

Russian nuclear program Large scale domestic construction of VVER1200 (Kaliningrad, Leningrad-2, Rostov,Novovoronezh-2, Nizhniy Novgorod, Kursk…)
 VVER-1200 foreign constructions (China, India,Turkey, Vietnam,…) Fast reactors with closed fuel cycle R&D
program (Beloyarskaya BN-1200, BREST,…)
 SMRs (floating, SVBR, VBR, VVER-640…)

15

Operating Russian nuclear plants
10 NPPs, 33 units, Ninst.=25242 MW

16

NPP
NPP Operator
Operator -- JSC
JSC “Concern“Concern Rosenergoatom”
Rosenergoatom”
Rosenergoatom was established on 07.09.1992 as NPP
Operator by the RF President’s Decree

33

17- number of existing power units

25242

MWt- the installed capacity

177.3

bln kW-h- generated in 201235

thous. pers.

- Rosenergoatom’s employees

18
Leningrad-II
NPP
Unit 1

NV-II NPP
Unit 2

Leningrad-II
NPP
Unit 3
Nizhny Novgorod
NPP
Unit 1

Leningrad-II
NPP
Unit 4

Baltic NPP
Unit 2Beloyarsk NPP
Unit 5
Kursk-II NPP
Unit 1

Central NPP
Unit 1Кola-II NPP
Unit 2Beloyarsk NPP
Unit 6

Seversk NPP
Unit 1(BN-1200)(BN-1200)

Kursk-II NPP
Unit 2

Nizhny Novgorod
NPP
Unit 2(BN-1200)

Rostov NPP
Unit 4

Baltic NPP
Unit 1

Leningrad-II
NPP
Unit 2(BN-800)

NV-II NPP
Unit 1

Beloyarsk NPP
Unit 4

Unit 4

Kalinin NPP

Кola-II NPP
Unit 1

Rostov NPP
Unit 3

RussianRussian nuclear
nuclear power
power roadmap
roadmap

The Number of Deaths and Early Effects of Radiation Accidents
Based on published data(except for malicious acts and nuclear weapon tests)

Type of accident

1945-1965

1966-1986

1987-2007

46 earlyeffects

227 early
effects *2 early
effects

275 early
effects

16 deaths

40 deaths*

3 deaths

59 deaths

8 earlyeffects
0 deaths5 early
effects
7 deaths
1 early effectno data

109 early
effects
20 deaths
60 earlyeffects
10 deaths
21 earlyeffects
0 deaths
470 early
effects
3 deaths

49 earlyeffects
5 deaths
204 early
effects
16 deaths
5 earlyeffects
0 deaths
143 early
effects
42 deaths

166 early
effects
25 deaths
269 early
effects
33 deaths
27 earlyeffects
0 deaths
613 early
effects
45 deaths

Early effects

60

887

403

1350

Deaths

23

73

66

162

Accidents at nuclear
facilities

Occupational accidents

Incidents with orphan IRS

Accidents during research
projects
Accidents during medicaluse

0 deaths
no data

Total

Opinion of the Committee
regarding the Reportcompleteness
Most of the deaths and manyinjuries were likely reported.

A number of deaths and injuries
were not likely reported.
A number of deaths and injuries
were not likely reported.
A number of deaths and injuries
were not likely reported.
It is evident that many deaths and asignificant number of injuries werenot reported.

TOTAL

Table 10 p.52 of Appendix R.671 to the UNSCEAR 2008 Report

19Summary
Summary Data
Data forfor Major
Major (>(> 55 Victims)
Victims) Accidents
Accidents ininthethe Energy
Energy Sector
Sector inin 1969-2000
1969-2000
OECD countries

Non-OECD countries

TypeAccidents

Victims

Victim/GW

Accidents

Victims

Victim/GW

Coal75

2259

0.157

1044

18 0170.597

Coal (data for
China, 19941999)

819

11 334

6.169

Coal (excludingChina)

102

4831

0.597

Oil165

3713

0.132

232

16 5050.897

Natural gas

90

1043

0.085

4510000.111

Oil & gas

59

1905

1.957

46

2016

14.896

Hydropower

1140.003

1029 924

10.285

Nuclear power

00-1

31*0.048

Total390

8934

1480

72 324* Instant deaths only

20

What
What waswas wrong?
wrong?

 Main safety objective: the protection of thepublic from excessive exposure, is not accurate.
 Core melt accidents with low or no radiation
effects used to have large scale consequences
because of public illiteracy, contradictory healthregulations, bad communication…

21

General outcomeof the Fukushima Daiichi accident
1.

It is now clear that many factors contributing to theFukushima accident were identified prior to theaccident:
 poor severe accident management planningstructure; lack of safety improvements;
 inadequate evaluation of external hazards;
 weak regulatory system; lack of training of personnel on emergency
preparedness.

2.
22

The necessary measures to address theseshortcomings were not put in place.

TestsTests ofof defense-in-depth
defense-in-depth efficiency
efficiency have
have been
been done:
done:- for each power unit in operationin Russia- taking into account allcredible extreme impacts on
NPP that are specific for theplacement region- taking into account various
combinations of the extreme
impacts23Results of the in-depth assessment

1
UpgradingUpgrading
works
worksaimed
aimed
at safety
at safety
improvement
improvementofofNPPs
NPPshave
have
beenbeen
implemented
implemented
duringduringlast
last10
10– 15– 15years
years

24

2

Vulnerabilities
and initial
events havebeen revealed
for each NPP

3Implementationofsupplementarymeasuresaimed atenhancementof NPProbustness isneeded4

Not all BDBA
initial eventswereconsidered indesigns of theoperating
NPPs

 Total loss ofheat removalfrom the reactorcore Complete anddurable (over 10days) loss ofNPP
connections toexternal powersources Combinationof 2 or more
independent
initiating events

Additional measures to improvesafety of Russian NPPs
Near-term actions
 Purchasing and equipping the plants with portableengineering means to be used for elimination ofsevere BDBAs:
 Diesel generators,
 Diesel-driven pumps,
 Motor-driven pumps, etc.

Medium- and long-term actions
 Analysis and development of specific supplementary
design solutions to be implemented at each NPP

25

Introduction of mobile emergency
equipment at NPPs
In 2012, the following equipment was delivered
to 10 Russian NPPs:

31 units

36 units

35 units

80 units

182 units
26

ScaleScale ofof thethe Problem
Problem

What
What dodo youyou know
know about
about thethe victims
victims ofof military
military andand peacefulpeaceful atom?
atom?

Students
EventHiroshima

Chernobyl
27

Real number of victims

Students’evaluations

Immediate and quick death of 210 000 people

About
300 000 people

Remote consequences among
86572 hibakushas– 421 people

750 000 people

Immediate and quick death of 31 people

40 000 people

Remote consequences(liquidators and population)  60 people

250 000 people

Software and hardware systems (SHS)• SHS for rescue units of
the State Corporation"Rosatom" to assess theconsequences of radiation
accidents to theenvironment (air, water)
and the population• SHS with 3-D models toassess the effects ofradiation accidents incomplex industrial
environment

28

Systems of emergency response andradiation monitoring in the RF regions
Territorial systems are created in the RF regions, whereoperational NPPs and NPPs under construction arelocated, to support local authorities functioning and todemonstrate safety of the NPP’s operation(system of emergency preparedness and independentradiation monitoring)
Scope of work:•Establishment of crisis centers;•Creation of territorial automated system of radiation
monitoring;•Development and equipment of software & technicalsystems;•Creation of mobile laboratory facilities;•Conduct of exercises and training.

29

Incident analysis for Fukushima-1 units 1-3
and spent fuel pool 4 (SOCRAT)
Without water cooling taken into account30

Reactor BWR/3 calculation
model for SOCRAT code

Atmosphere transfer modeling withaccount of detailed weather data in Japan
Modeling results and monitoring data■■ -- Model
Model▲▲ -- ARMS
ARMS measurement
measurement●● -- DOE
DOE monitoring
monitoring

31

Fukushima
Fukushima experience
experience
Territories and population in the areas with expected annual
dose for population above 20 and 100 mSv
after the Fukushima NPP accident
Expected annual dose,mSv/yearTotal
In 20-km Area, km2
Populatedzone
Population, individuals
Total
Out 20- Area, km2
Populated
km zonePopulation, individuals
Total
Area, km2
Total
Populated
Population, individuals
32> 20327
109
43 700368
84
16 300695
19360 000> 100101
248750531140001543512 550

Fukushima
Fukushima experience
experience
Recommendations on protective measures For major part of the Japanese territory, the total radiation exposure doses
for population for 20 days after the accident did not exceed 0.1 mSv. No
protective measures are required.
 The total dose for population for 20 days in the most contaminatedprefecture Ibaraki reached 0.6-1.0 mSv. Such prevention measure ascontrol of milk and vegetable contamination for the first month isrecommended.
 In the north-west trace out the boundary of 20-km area, the maximal
doses for 20 days could reach 50 mSv. The expected dose for the firstyear without protection measure could reach total 150 mSv. Population
evacuation is not justified. Deactivation, regular control over food andwater contamination and some other measures are recommended.

In April 2012, WANO MC’s Board of Governors adopted theidea proposed by Operating organizations to establish
WANO MC Regional Crisis Center (RCC)

34

RCC

1. Early notification and exchange ofcredible information between WANO
MC Members in case of an accident ora safety important event occurred atNPP.
2. Establishing the Expert Community
to provide real-time consultations andearly engineering and technicalsupport on request of an emergency
NPP.
3. Establishing mechanisms for earlyprovision of materials and technicalresources as assistance of WANO MCMembers on request of an emergency
NPP.

35

What to do Detailed safety analysis of low probable scenarioswith severe consequences.
 A global consensus on a set of accidents that should
be considered and could be ignored.
 For severe, although low-probable accidents,
protective measures should be included.
 The 100 times gap between radiation effect andregulation should be bridged.
 Public information should be an essential part of theatomic energy use.
 National technical centers should support emergency
response to radiological incidents.
36

Conclusion

 Include into consideration the unlikely, thoughsevere, accidents and eliminate them bydeterministic methods;
 Be fully prepared for emergency response; Clear the rules for radiation protection;
 Provide the public involvement in the issuesof radiation and nuclear technology safety.

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