Considering the situation of the damages at Fukushima Daiichi Nuclear
Power Station and Fukushima Daini Nuclear Power Station caused by the
Tohoku-Chihou-Taiheiyou-Oki Earthquake on March 11th, 2011, we have taken
measures to improve waterproof performance of each building in Kashiwazaki
Kariwa Nuclear Power Station after the earthquake.
Also on the assumption that tidal waves that are hard to expect cause the
blackout in the station (lose all alternating-current power), we have
installed facilities on the upland in the site for back-up power supply,
injection of water in reactors and spent fuel pools and securement of
cooling system. As stated above, we have taken measures to ensure cooling
function in case of water exposure due to tidal waves inside the buildings.
(Previously announced on March 30th, 2011)
Then we have been considering further safety measures against tidal waves
that are hard to expect, consulting with the Ministry of Economy, Trade
and Industry (METI) and we have determined that we will build new tide
barriers in the nuclear reactor buildings of Unit 1 to 4 in order to
prevent the buildings from being flooded.
We plan to prevent the waves from flooding inside the nuclear reactor
buildings where important facilities in terms of safety such as
power-supply facilities and emergency diesel electric power generator are
installed and to ensure the fundamental safety in the station.
We will design the details such as the height of the tide barriers and
begin the installation construction in a rapid manner.
We will organize and consider countermeasures regarding safety including
the ones implemented so far based on the instructions of METI and Nigta
Prefecture, and will report them.
Also we will further improve the safety in the station by analyzing and
evaluating the circumstances of the accident in Fukushima Daiichi Nuclear
Power Station hereafter.
Attachment: The image of installation of tide barriers in Kashiwazaki
Kariwa Nuclear Power Station (PDF 92.3KB)