1. Niigataken Chuetsu-oki Earthquake and its Influences on the Kashiwazaki-Kariwa NPP

2. Summary of the Earthquake and Situation of the Kashiwazaki-Kariwa NPP
Occurrence: July 16, 2007 at 10:13 am JST
Earthquake Source:
17km below the seabed off Jo-chuetsu area in Niigata prefecture (37°33.4′North、138°36.5′East）
Epicenter Distance: 16km from the NPP
Magnitude: 6.8
Situation of the NPP
When the earthquake occurred:
Unit 2 was in start-up
Unit 3, 4 and 7 were in normal operation
Unit 1, 5 and 6 were out of operation for the periodic inspections
Units 2, 3, 4 and 7 were automatically shut down following the high seismic acceleration trip signals
Kashiwazaki-Kariwa NPP
Niigata city
Epicenter

3. Rx. Coolant Temp. Rx. Water Level Unit 2 under Stat up
19:40 <100℃
Unit 3 100% Power
23:07 <100℃
Unit 4 100% Power
7/17 6:54 <100℃
Unit 7 100% Power
7/17 1:15 <100℃

4. Unit 1 RPV Inspection Schedule
August
September
October
November
December
Phase 1
Phase 2
Phase 3
8/21
8/23
Visual inspection using under water TV camera

5. Unit 1 : Phase 1 Inspection
Flange
Upper Grid
Guide Rod
Feed Water Sparger
Core Shroud
Core Spray Pipe
Core Spray Sparger
As a result of phase 1 inspection, the abnormality such as the damage / transformation / the falling off was not confirmed.

6. Unit 1 : Flange
Guide Rod
Flange

7. Unit 1 :Guide Rod
Guide Rod
FW Sparger
Core Spray Pipe

8. Unit 1 :Feed Water Sparger

9. Unit 1 :Core Spray Pipe

10. Unit 1 :Core Spray Sparger
Core Shroud(upper ring)
Core Spray Sparger

11. Unit 1 :Upper Grid
LPRM

12. Unit 1 : RPV base bolts(A,As)

13. Unit 1 : Leakage of water into B5 floor
Break of Fire Extinguishing Pipe (B,C)
B1 Floor
B2 Floor
B3 Floor
B4 Floor
B5 Floor
Sump
Duct
Reactor Combination Building
Pene
Water Flow-in
Leakage of water into B5 floor of
the reactor combination building (Unit 1)

14. Unit 1 : Oil Tank (B,C)
Land Subsidence

15. Unit 3 :Fire of House Transformer(1/3)
(B,C)
As for the duct, cm dropped

16. Unit 3 :Fire of House Transformer(2/3)
Bedrock
House Transformer
Bus Duct
1 – 3 cm dropped
20 – 25 cm dropped

17. Unit 3 :Fire of House Transformer(3/3)
Unit 3 Main Transformer
Unit 3 Main Generator
House Transformer
Start-up Transformer
Emergency Bus
Normal Bus
Fire of House Trans. was not safety related problem

18. Unit 3 : DG(A,As)
Upside
Downside

19. Unit 3 : HCU (A,As)( Hydraulic Control System (CRD))

20. Unit 3 : MSIV (A,As)

21. Unit 3 : PLR Pump (A,As)

22. Unit 3 : RHR Pump (A,As)

23. Unit 3 : Blow-out Panel came off
(B,C)

24. Unit 3 : Displacement of the main exhaust duct
(B,C)

25. Unit 6 : Leakage of water including radioactive materials
(B,C)
Leakage of water including radioactive materials into non-controlled area in the reactor building

26. Unit 6 : Leakage of water including radioactive materials
Leakage of water including radioactive materials into non-controlled area in the reactor building

27. Unit 6 : Damage of the reactor building overhead crane
Motor
Damaged
Damage found on the coupling of the drive axis
of the reactor building overhead crane

28. Unit 7 : Detection of radioactive materials in the main exhaust duct
Duct Monitoring
House
Main Exhaust Duct
Filter
Reactor Building
Turbine
Building
Reactor
Conden-ser
Rare Gas Hold
-up Equipment
Turbine Gland
Steam Exhauster
Building Ventilation
Still Working
after Plant Shutdown
Detection of radioactive materials in the main exhaust duct resulting from loss of the steam seal inside the turbine

29. Other (B,C)

30. Solid waste storage warehouse