On May 16, 2011, we received an instruction* from Nuclear and Industrial
Safety Agency (NISA) of Ministry of Economy, Trade and Industry titled
"Countermeasures based on a report on records of damage situation of
power facilities inside and outside of Fukushima Daiichi Nuclear Power
Station (instruction)"
(Previously announced on May 17, 2011)
Thereafter we put together the contents in a report on the result of
investigation of causes that brought about damage situation of power
facilities inside and outside of Fukushima Daiichi Nuclear Power Station
and those why protective devices of transmission lines worked and
electric transmission was suspended (Countermeasures in the future are
included in the result). We announce we submitted the report to NISA
yesterday on May 23.
END
○ Attachment
·Our report on "Countermeasures based on a report on records of damages
to power facilities inside and outside of Fukushima Daiichi Nuclear
Power Station (instruction)"
* Countermeasures based on a report on records of damage to power
facilities inside and outside of Fukushima Daiichi Nuclear Power
Station (NPS) (instruction)
2011.05.16 NISA no. 7
Today on May 16, with regard to collection of a report pursuant to the
provisions of Article106, paragraph 3 of the Electricity Business Act
(Act No. 170 of 1964), we received a report from your company on damage
situation of power facilities, electric transmission to NPS and
restoration situation of off-site power by urgent measures inside and
outside of NPS since the occurrence of the Tohoku-Chihou-Taiheiyou-Oki
Earthquake (Earthquake).
We, Nuclear and Industrial Safety Agency (NISA), determine we have to
make clear causes that brought about damage situation of power facilities
inside and outside of NPS in the report and those why protective device
of transmission lines worked and electric transmission was suspended in
order to utilize study to further enhance reliability of power supply
to nuclear power stations.
Hence, we request that you report the following items to us by May 23,
2011.
Required Items
1. Results of determination why the following items and other electric
facilities inside and outside of NPS have caused damage situation
since Earthquake occurred; especially, you should analyze whether
damage situation was caused by Earthquake or the tsunami by operation
records including those just after the earthquake occurred and accident
records in nuclear reactor facilities stipulated in paragraph 1 of
Article 7 of Order on Installation and Operation of Nuclear Reactors
for Commercial Power Generation (Order No.77 of Ministry of
International Trade and Industry of 1978) regarding the current
accident at NPS in accordance with the provisions of Article 67,
paragraph 1 of Act on Regulation of Nuclear Source Material, Nuclear
Fuel Material and Reactors (Act No. 166 of 1957) by records in the
report and Nuclear No.1 on April 24, 2011 dated on April 25, 2011.
○Fukushima Daiichi Nuclear Power Station
·Causes why power receiving circuit breakers and disconnecting
switches were damaged
·Causes of troubles on electric wires connecting Toden Genshiryoku
Line
·Causes of collapse of a high tension tower of Yonomori Line No.27
·Causes why regular and emergent power distribution panels were
damaged
○Shin Fukushima Electric Power Substation
·Causes why major transformers were damaged
·Causes why circuit breakers were damaged
·Causes why disconnecting switches were damaged
·Causes why instrument transformers were damaged
·Causes why current transformers were damaged
2. Results of determination why protective devices of the following
transmission lines worked and electric transmission was suspended
○Fukushima Daiichi Nuclear Power Station
·Okuma Line No.1
○Shin Fukushima Electric Power Substation
·Okuma Line No.2, 3 and 4
·Yonomori Line No. 1 and 2
