Fukushima Daiichi NPS Prompt Report 2013

This is follow-up information on the "water leak at a tank in the H4 area in Fukushima Daiichi Nuclear Power Station" found on August 19.

During a patrol yesterday (on September 3), we detected high does equivalent rates at the 2 locations in the H3 area which we previously announced as having showed high dose equivalent rates (β and γ rays (70μm dose equivalent rate^*1)). We conducted dose measurement at these locations using a high-range measuring device also.
*1: 70μm dose equivalent rate = dose equivalent rate to the skin, etc.

In addition, on Tank No.7 in Group A in the H6 area around which a high dose equivalent rate (β and γ rays (70μm dose equivalent rate^*1)) was detected on September 2, we conducted dose measurement using a high-range measuring device also. The dose rate detected at the 50-cm distance today was 5.5mSv/h and did not exceed 10mSv/h.

· Tank No.4 (north side) in Group B in the H3 area: 40mSv/h (at the 50-cm distance)^*2, 2,200mSv/h (at the 5-cm distance)^*2
· Tank No.4 (south side) in Group B in the H3 area: 10mSv/h (at the 50-cm distance)^*2, 400mSv/h (at the 5-cm distance)^*2
· Tank No.7 in Group A in the H6 area: 5.5mSv/h (at the 50-cm distance)^*2, 300mSv/h (at the 5-cm distance)^*2
*2: Values of 70μm dose equivalent rates (β ray).
(Values of 1cm dose equivalent rates (γ ray) were less than 1mSv/h.)

Further, we have confirmed that the water levels of the tanks in the group including Tank No.7 in Group A in the H6 area have been unchanged.