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Kashiwazaki-Kariwa Technical Report

Impact of Chuetsu Oki Earthquake (16 July 2007) on Kashiwazaki-Kariwa Nuclear Power Plant

Extract from Tokyo Electric Power Company's (TEPCO) 10 August 2007 report
(Neutron Flux and Reactor Pressure Charts: CNIC Provisional Translation)

TEPCO's 10 August 2007 report included (1) a list of abbreviations, (2) the position of control rods, (3) computer print outs, (4) the following charts:

4-1 neutron flux
4-2 reactor pressure
4-3 reactor water level (upset range / narrow range)
4-4 reactor temperature
4-5 exhaust stack radiation monitor
4-6 reactor flow
4-7 main steam flow / feedwater flow

Citizens' Nuclear Information Center (CNIC) translated the following charts:

4-1 neutron flux (Word File 56KB)
4-2 reactor pressure (Word File 116KB)

TEPCO's original document is locked, so it was not possible to write the English onto the charts themselves. Instead we have listed the comments more or less in the order that they appear in the charts. We hope that enough will be discernable from the Japanese charts to enable trained readers to work out how the translation relates to the original charts. In some places we were not sure of the precise English translation, but we hope that our approximation is near enough to enable trained readers to interpret the charts.

The original Japanese charts can be found on TEPCO's web site at the following links:

Neutron Flux

Reactor Pressure

CNIC contacted TEPCO to find out if it intended to translate these charts into English. It said that it did not. Our purpose in translating the charts was twofold:

1) to give non-Japanese people an opportunity to make a technical analysis of some key data related to the behavior of the Kashiwazaki-Kariwa nuclear power plant during the 16 July 2007 Chuetsu-Oki Earthquake;
2) to encourage TEPCO to provide English translations of all relevant technical information.

In addition to full English translations of the 10 August report, we also call on TEPCO to provide full translations of the other technical reports relating to the Chuetsu-Oki Earthquake which have been published in Japanese, including reports released on 22 and 23 August 2007.

Abbreviations (including some not used in the translated charts) are as follows:

APRM Average Power Range Monitor
IRM Intermediate Range Monitor
SRM Source Range Monitor
SRNM Startup Range Neutron Monitor
MRBM Multi-channel Rod Block Monitor
RIP Reactor Internal Pump
PLR Primary Loop Recirculation System
MSIV Main Steam Isolation Valve
TBV Turbine Bypass Valve
SRV Safety Relief Valve
RHR Residual Heat Removal System
SHC Shut-down Cooling System
CUW Clean Up Water System
D/W Dry/Well
TGS Turbine Ground Steam Seal System
SJAE Steam Jet-Air Ejector
(S-SJAE) (Starting Steam Jet-Air Ejector)
(M-SJAE) (Main Steam Jet-Air Ejector)

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Citizens' Nuclear Information Center
Akebonobashi Co-op 2F-B, 8-5 Sumiyoshi-cho,
Shinjuku-ku, Tokyo, 162-0065, Japan