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.

We performed the analyses of water sampled on September 15 in the observation holes (E-1: in north of the tank No.5 in Group I in the H4 area (outside of a dike) where water leakage was found, E-2: in south of the tank No.5 in Group I in the H4 area (outside of a dike) where water leakage was found) around the H4 tank area.

The result of tritium obtained in E-1 (140,000Bq/L) has decreased compared with the result obtained on September 14 (170,000Bq/L).
No significant change was found on the result of tritium obtained in E-2 compared with the result obtained on September 14.

In addition, the result of all β obtained this time in a newly analyzed observation hole (E-4) around H4 tank area was below the detection limit value (detection limit value: 120 Bq/L).

<Observation hole: E-1>
- Sampled on September 15
 Tritium: 140,000 Bq/L
 All β: 1,100 Bq/L (previously announced)

- Sampled on September 14
 Tritium: 170,000 Bq/L (previously announced)
 All β: 1,100 Bq/L (previously announced)

- Sampled on September 13
 Tritium: 150,000 Bq/L (previously announced)
 All β: 1,300 Bq/L (previously announced)

- Sampled on September 12
 Tritium: 130,000 Bq/L (previously announced)
 All β: 1,600 Bq/L (previously announced)

- Sampled on September 11
 Tritium: 97,000 Bq/L (previously announced)
 All β: 1,500 Bq/L (previously announced)

- Sampled on September 10
 Tritium: 64,000 Bq/L (previously announced)
 All β: 2,000 Bq/L (previously announced)

<Observation hole: E-2>
- Sampled on September 15
 Tritium: 400 Bq/L
 All β: 35 Bq/L (previously announced)

- Sampled on September 14
 Tritium: 360 Bq/L (previously announced)
 All β: 21 Bq/L (previously announced)

- Sampled on September 13
 Tritium: 410 Bq/L (previously announced)
 All β: Below the detection limit value (detection limit value: 15 Bq/L)
(previously announced)

- Sampled on September 12
 Tritium: 290 Bq/L (previously announced)
 All β: 29 Bq/L (previously announced)

- Sampled on September 11
 Tritium: 300 Bq/L
 All β: Below the detection limit value (detection limit value: 20Bq/L)
(previously announced)

<Observation hole: E-4>
- Sampled on September 15
 Tritium: Below the detection limit value (detection limit value: 120Bq/L)
 All β: 1,300 Bq/L (previously announced)