Fukushima Daiichi NPS Prompt Report 2013

This is follow-up information regarding the water leak from the underground reservoirs at Fukushima Daiichi NPS.

The results of chloride concentration analysis performed in the drain holes of the underground reservoirs No.1-7 (14 locations) and the leakage detection holes of the underground reservoirs No.1-4 and 6 (sample could not be collected at 2 out of 10 locations) today (May 23) are as follows.

No significant change was found with the chloride concentration analysis results compared to yesterday (May 22).

In addition, we would like to announce the results of all β analysis performed in the observation holes at 2 locations (2-8 and 2-13) which was newly drilled today (May 23), and reanalysis performed in the observation hole 2-10 and 2-11 where all β was detected yesterday (May 22). (There will be 6 newly added observation holes from 2-8 to 2-13.)

The all β densities detected in the observation hole 2-10 was equivalent to those announced yesterday and the all β densities detected in the observation hole 2-8, 2-11 and 2-13 were below the detection limit.
- Underground reservoir observation hole 2-8: Below the detection limit (detection limit: 3.2 × 10^-2Bq/cm³)
- Underground reservoir observation hole 2-10: 7.1 × 10^-2Bq/cm³ (Analysis result as of May 22: 1.0 × 10^-1Bq/cm³)
- Underground reservoir observation hole 2-11: Below the detection limit (detection limit: 3.3 × 10^-2Bq/cm³)
- Underground reservoir observation hole 2-13: Below the detection limit (detection limit: 3.2 × 10^-2Bq/cm³)

Analysis of the observation hole 2-1 to 2-13 is scheduled tomorrow (May 24).

Please visit our web page for the sampling results.
http://www.tepco.co.jp/en/nu/fukushima-np/f1/smp/2013/images/chosui_13052303-e.pdf

The water level, etc. of the underground reservoirs will continue to be intensively monitored.

[Chloride concentration analysis results on May 23]

- Drain hole (northeast) of the underground reservoir No.1
Sampling performed at 9:02 AM on May 23
Chloride concentration: 12ppm

- Drain hole (southwest) of the underground reservoir No.1
Sampling performed at 9:10 AM on May 23
Chloride concentration: 7ppm

- Drain hole (northeast) of the underground reservoir No.2
Sampling performed at 8:55 AM on May 23
Chloride concentration: 10ppm

- Drain hole (southwest) of the underground reservoir No.2
Sampling performed at 9:01 AM on May 23
Chloride concentration: 7ppm

- Drain hole (northeast) of the underground reservoir No.3
Sampling performed at 8:47 AM on May 23
Chloride concentration: 9ppm

- Drain hole (southwest) of the underground reservoir No.3
Sampling performed at 8:54 AM on May 23
Chloride concentration: 5ppm

- Drain hole (northeast) of the underground reservoir No.4
Sampling performed at 8:39 AM on May 23
Chloride concentration: 10ppm

- Drain hole (southwest) of the underground reservoir No.4
Sampling performed at 8:44 AM on May 23
Chloride concentration: 9ppm

- Drain hole (northeast) of the underground reservoir No.5
Sampling performed at 8:25 AM on May 23
Chloride concentration: 9ppm

- Drain hole (southwest) of the underground reservoir No.5
Sampling performed at 8:20 AM on May 23
Chloride concentration: 9ppm

- Drain hole (northeast) of the underground reservoir No.6
Sampling performed at 8:38 AM on May 23
Chloride concentration: 10ppm

- Drain hole (southwest) of the underground reservoir No.6
Sampling performed at 8:29 AM on May 23
Chloride concentration: 10ppm

- Drain hole (northeast) of the underground reservoir No.7
Sampling performed at 8:45 AM on May 23
Chloride concentration: 6ppm

- Drain hole (southwest) of the underground reservoir No.7
Sampling performed at 8:49 AM on May 23
Chloride concentration: 9ppm

- Leakage detection hole (northeast) of the underground reservoir No.1
Sampling performed at 8:14 AM on May 23
Chloride concentration: 23ppm

- Leakage detection hole (southwest) of the underground reservoir No.1
Sampling performed at 8:16 AM on May 23
Chloride concentration: 6ppm

- Leakage detection hole (northeast) of the underground reservoir No.2
Sampling performed at 8:20 AM on May 23
Chloride concentration: 11ppm

- Leakage detection hole (southwest) of the underground reservoir No.2
Sampling performed at 8:26 AM on May 23
Chloride concentration: 13ppm

- Leakage detection hole (northeast) of the underground reservoir No.3
Sampling performed at 8:26 AM on May 23
Chloride concentration: 10ppm

- Leakage detection hole (southwest) of the underground reservoir No.3
Sampling performed at 8:34 AM on May 23
Chloride concentration: 10ppm

- Leakage detection hole (northeast) of the underground reservoir No.4
Sampling performed at 8:34 AM on May 23
Chloride concentration: 9ppm

- Leakage detection hole (southwest) of the underground reservoir No.4
*Sampling was not performed since the amount of sample necessary for analysis could not be obtained.

- Leakage detection hole (northeast) of the underground reservoir No.6
Sampling performed at 8:34 AM on May 23
Chloride concentration: 6ppm

- Leakage detection hole (southwest) of the underground reservoir No.6
*Sampling was not performed since the amount of sample necessary for analysis could not be obtained.