We are announcing the status of major inspections and restoration works and
nonconformances at TEPCO's Kashiwazaki-Kariwa Nuclear Power Station after
the Niigata-Chuetsu-Oki Earthquake.
1. Inspection/Restoration Status
○ Inspection and restoration completed between November 9th to November 15th, 2007
(Completed on the following date)
• Unit No.1 Refueling machine inspection:
Planned to be completed on November 15th
• Unit No.2 Reactor pressure vessel inspection (support structure):
November 14th
• Unit No.2 House transformers (2A) oil extraction and internal inspection:
November 13th
• Unit No.2 House transformers (2B) visual inspection:
Planned to be completed on November 15th
• Unit No.3 Reactor pressure vessel inspection (support structure):
November 12th
• Unit No.4 Reactor building ceiling crane inspection:
November 9th
• Unit No.4 Reactor pressure vessel inspection (support structure):
November 12th
• Unit No.6 Refueling machine inspection:
November 12th
• Unit No.6 Reactor head opening:
November 12th
• Unit No.6 Removal of spent fuel pool underwater work platform:
November 14th
• Unit No.7 Reactor-well inspection:
Planned to be completed on November 15th
• Unit No.7 House transformers (7A) oil extraction and internal inspection:
November 14th
• Unit No.7 House transformers (7B) oil extraction and internal inspection:
November 10th
• Unit No.7 Verification operation of feedwater pump and condensate pump:
November 12th
• Dismantling of Arahama-side arrestor steel tower:
November 12th
○ Inspection and restoration to be commenced between November 16h to November 22nd, 2007
(To be commenced on the following date)
• Unit No.1 Main transformer oil extraction and internal inspection:
November 19th
• Unit No.1 Inspection of skimmer surge tank:
November 19th
• Unit No.2 Preparation for reactor internal inspection (Phase3):
November 16th
• Unit No.2 House transformers (2B) oil extraction and internal inspection:
November 16th
• Unit No.2 Excitation transformers visual inspection and preparation for oil extraction
and internal inspection:
November 16th
• Unit No.3 Turbine internal inspection:
November 21st
• Unit No.5 Reactor pressure vessel inspection (nozzle parts etc):
November 13th*
• Unit No.5 Main transformer preparation for oil extraction and internal inspection:
November 16th
• Unit No.6 Reactor internal pump input transformer (transportation into the factory):
November 20th
• Unit No.7 Preparation for reactor internal inspection (Phase1 and 2):
November 20th
• Unit No.7 Fuel, control rod inspection:
November 17th
• Unit No.7 Reactor internal pump input transformer (transportation into the factory):
November 19th
• High-voltage start-up transformer No.1 preparation work for installation:
November 19th
*Work schedules that have been fixed after the weekly report announced last week.
○ Work Schedule for Major Inspection/Restoration from November 11th to December
8th, 2007
• Work Schedule of the Main Inspection/Restoration of Kashiwazaki-Kariwa Nuclear
Power Station in Response to the Niigata-Chuetsu-Oki Earthquake (during 4 Weeks)
•••Appendix
2. Nonconformances Found in the Inspection and Restoration Works Performed after
the Niigata-Chuetsu-Oki Earthquake
Based on the "Public Announcement Regarding Nonconformance Found in the Inspection
and Restoration Works Performed after the Niigata-Chuetsu-Oki Earthquake", the Tokyo
Electric Power Company, Incorporated (TEPCO) provides this announcement containing
incidents information reported from November 8th to November 14th, 2007.
○ Incidents Information (relating to the Chuetsu-Oki Earthquake)
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<Reports from Nov. 8 to Nov. 14, 2007>
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○ Other Findings
• Verification run of emergency core cooling systems (ECCSs) has been completed
except for those at unit No.1 which was during a regular outage at the time of
the earthquake. No abnormality was found in any of the ECCS (Nov. 9th).
• Unit No.7:
Reactor well inspection was completed on Nov. 14th. Two minor scratches
(approximately 3mm and 2mm long) that led to a leak were found. Temporary repair
of the scratches-covering the scratches with stainless steal plates to prevent
leakage-has been implemented on Nov. 14th. Root cause analyses will be carried
out by analyzing the seismic impact load of the concrete radiation shield block
and conducting a mock-up test of the weld at a factory.
• Unit No. 5:
A visual inspection of the fuel assembly, which could not be pulled out initially
while the in-core inspection, was conducted via an underwater camera. A misalignment
of a fuel assembly and its fuel support was found (Nov. 11th). There is no visual
abnormality such as deformation on either the fuel assembly or the fuel support in
question (announced on Nov. 14th). After the transfer of fuel assembly in question
to the spent fuel pool, the investigation will be continued.
• Unit No. 2:
Phase 1 and 2 of the in-core inspection, originally scheduled from Nov. 3rd to 14th
was extended until today since a filiform pattern was found on the exterior surface
of the shroud support cylinder.
Since all filiform pattern disappeared after polishing them with a rubber pallet,
crud deposition such as iron rust and other metal impurities is presumed to have
caused the pattern.
• Unit No. 6:
Minor scratches-three on the underwater work platform and three on the spent fuel
pool wall-were found during visual inspection of the spent fuel pool conducted
subsequent to the removal of the spent fuel pool underwater work platform
(both completed on Nov. 14th).
Appendix: Work Schedule of the Main Inspection/Restoration of Kashiwazaki-Kariwa Nuclear
Power Station in Response to the Niigata-Chuetsu-Oki Earthquake
(during 4 Weeks)(PDF 230KB)
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