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.

On September 8, we performed the analyses of γ nuclide and all β for the first time in an observation hole (E-1: in north of a dike of the tank No.5 in I Group in the H4 area with water leakage) around H4 tank area. The results are as follows.

<Observation hole: E-1>
- Sampled on September 8
Tritium: 4200 Bq/L
Cesium-134: 2.5Bq/L (previously announced on September 9)
Cesium-137: 5.1bq/L (previously announced on September 9)
All β: 3200Bq/L (previously announced on September 9)

The result of tritium in groundwater (E-1) in H4 area (sampled on September 8 for the first time) was 4200Bq/L, and was higher than the radioactive concentration measured at the observation hole E-2, likewise the result of all β measured on the same day (on September 8).

We performed the analysis of tritium (sampled on September 8) in water in an observation hole (E-2: in south of a dike of the tank No.5 in I Group in the H4 area with water leakage) around H4 tank area. The results are as follows.

<Observation hole: E-2>
- Sampled on September 8
Tritium: 290 Bq/L
Cesium-134: 0.64Bq/L (previously announced on September 9)
Cesium-137: 0.74Bq/L (previously announced on September 9)
All β: 67Bq/L (previously announced on September 9)

- Sampled on September 7
Tritium: 300Bq/L (previously announced on September 9)

The result of tritium obtained on September 8 in an observation hole E-2 was 290Bq/L, and this is approximately the same as the result of tritium (300 Bq/L) at the same point sampled on September 7.

We are determined to continue analyses and to monitor the situation.