the fukushima nuclear accident - european parliament · 2011-06-30 · european clearinghouse on oe...

European Clearinghouse on OE – Presentation to the EP STOA on the Fukushima nuclear accident – 09/06/2011 - Strasbourg 1

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The Fukushima nuclear accident

What happened? Consequences? JRC involvement?

Marc NoëlJoint Research Center – Institute for Energy

[email protected]://clearinghouse-oef.jrc.ec.europa.eu/


Initiating event : magnitude 9,0 earthquake

What happened at the Fukushima Daiichi Nuclear Power Plant on 11 March 2011?


NPP affected by the earthquake


Tsunami generated by the earthquake


Many significant aftershocks


The Fukushima Daiichi site

Source: AREVA.


Before / after tsunami Tank displaced?

Many structures facing the bay are destroyed

Missing tanks

Shared spent fuel storage


« GE Mark I » design


Event sequence (1)

• Diesel generators start.• Plant is in a stable state.


Event sequence (2)

• Reactors 1-3 are cut-off from any kind of heat removal.


Event sequence (5)

• Core starts to be exposed


• Cladding temperature rises• At 900°C: balooning, cladding breaking• At 1200°C: exothermic reaction Zr+2H2OZrO2+2H2• At 1800°C: melting of fuel cladding and steel structures.• At 2500°C: breaking of the fuel rods, debris bed inside the core.

• Pressure increase inside containment up to 8b->venting• Supply of seawater to the reactor stops the core melt

H2

H2

>900°C >1200°C >2500°C

N2

Event sequence (6)


Event sequence – Units 1&3


Service floor (top of the reactor building)


Event sequence – Unit 2


After the Hydrogen detonations


Unit 4

Unit 3

After the Hydrogen detonations


Fuel storage issue? (units 1 to 4)

Unit 3: Fuel stored in the pond not visible beneath a mass of steel beams, concrete, dust and rebar from the explosive destruction of the reactor building roof. Concrete dust appeared thick on the surface of flat objects and specks of dust were circulating in the warm water of the pond. [WNN]

Unit 4: a visual inspection by remote controlled camera has shown no significant damage to the spent fuel pond.


Example of recovery actions (1)



Water spray SFP4 using mobile truck

Temporary shelter (unit1, in project)


Summary of the situation

Unit 1 2 3 4 5 6Core and fuel integrity (loaded fuel assemblies)

Damaged most part

Damaged most part

Damaged most part

No fuel in the reactor

Not Damaged

Not Damaged

Reactor Pressure Vessel Integrity

Damage and leakage

estimated

Damage and leakage

estimated

Damage and leakage

estimated

Not Damaged

Not Damaged

Not Damaged

Containment IntegrityDamage and

leakage estimated

Damage and leakage

suspected

Damage and leakage

suspected

Not Damaged

Not Damaged

Not Damaged

Reactor building integrity Severely Damaged

Slightly Damaged

Severely Damaged

Severely Damaged

Vent hole opened on the rooftop for avoiding hydrogen explosion

Water injection to core Continuing (Freshwater)

Continuing (Freshwater)

Continuing (Freshwater)

Not necessary

Not necessary

Not necessary

Water injection to Containment Vessel Feed water Feed water

(planned)Feed water (planned)

Not necessary

Not necessary

Not necessary

Fuel integrity in the spent fuel pool (Stored fuel assemblies)

Unknown(292)

Unknown(587)

Damage suspected

(514)

Damage suspected

(1331)

Not damaged

(946)

Not damaged

(876)

Electric power supply off-site grid available

off-site grid available






What are the radiological consequences?


• 11/03: evacuation inside 3km. • 12/03 (increase RCV pressure

venting): evacuation inside 10km. • 13/03 (explosion @ unit1): evacuation

inside 20km (170000 residents) + iodine prophylaxis. 25 detected contaminated and decontaminated.

• 15/03: sheltering 30km + no fly zone.• 31/03: significant radioactivity level

detected in a village at 40km• CIPR recommends to “take protective

measures” when the yearly estimated dose is > 20-100 mSv.

• Based on local monitoring, extension of the evacuation zone decided. The new evacuation zone match +- the 20mSv yearly dose zone.


• blabla


Example of food bans


High Level EC Task Force for the follow-up of the EU answer to the nuclear accident in Japan

• Created on 30/05/2011 (SEC(2011) 706)Main objectives :• To oversee the implementation of the stress tests, with a view to reporting on

the process to the next European Council meeting of 9/12/2011.• To analyse the radiation protection measures taken so far and propose

corrective measures if needed.Membership:• Chair: the DG of DG ENER. Vice-Chair: the DG of DG JRC• ENER, JRC, SANCO, TAXUD, MOVE, RTD, DEVCO, SG, others…Key milestones:• KoM of the High Level EC Task Force yesterday.• 15 Sep: national progress reports from the national Regulators sent to EC • 15 Nov: EC viewpoint on the process – draft report for the European Council• 9 Dec: European Council• End of 2011: final national reports – opening the door for the peer reviews• 30 April 2012: completion of peer reviews.• June 2012: consolidated EC report to the Council.


The European Clearinghouse on Operational Experience Feedback for NPP

The European Clearinghouse for NPP OEF :a centralized initiative aiming at strenghtening OEF in the EU,to the benefit of the participating EU Safety Authorities,

in close collaboration with and their Technical Support Organisations (TSOs).

EU NPP safety assessments: JRC role?

Main role: support to the EC High Level Task Force(expertise in nuclear safety)


Role of the JRC in the EU NPP « stress tests »

• Expertise of the JRC in the field:• JRC has a long tradition of providing technical support in nuclear safety

(TACIS-INSC, PHARE-IPA, EURATOM art.41-45 for new NPPs, OSART missions, design review in Ukraine, …)

• JRC has expertise on the different types of power reactors being operated in the EU (PWR including VVERs, BWRs, CANDU, ...).

• Through the European Clearinghouse, JRC has the expertise of the analysis of nuclear events and accidents. In full cooperation with the EUMS nuclear Safety Authorities and TSOs.

• The JRC has expertise in the assessment of seismic and flooding hazards.


Role of the JRC in the EU NPP « stress tests »

• JRC gives its full support to the stress tests

• JRC has contributed to the definition of the scope and methodology for the stress tests and will further contribute to:

• the definition of common criteria• the peer-reviews. (reminder: 1 peer review team per EU MS operating NPP; 7

experts per team: 6 from MS safety authorities + 1 from EC-JRC).

• JRC will collect all the national reports for the EC

• JRC will contribute to the report of the EC to the European Council (see conclusions of the European Council of 24-25th March 2011)

• The JRC can/will support any international safety and risk analysis in neighboring countries, in partnership with the IAEA.


SOURCES: GRS, IRSN, TEPCO, NISA, MEXT, AREVA, ASN, IAEA, VGB, US-NRC,JAIF.

the fukushima nuclear accident - european parliament · 2011-06-30 · european clearinghouse on oe...

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