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 2) are as follows.

No significant change was found with the chloride concentration analysis results compared to yesterday (May 1).

The results of tritium sampling analysis performed from April 22 to 24 (analysis performed once a week) are also announced.
- Groundwater bypass (Investigation holes a-c, pump wells 1-4)
- Observation holes on the sea side (1)-(4) (Analysis performed for the first time)
- Drain holes of the underground reservoirs No.1-4 and 6
- Leakage detection holes of the underground reservoirs No.1-4 and 6

As a result of tritium analysis, tritium was detected in the drain holes (northeast) of the underground reservoirs No.4 and 6 (similarly to the previous results) as well as in the observation holes on the sea side (3) and (4). In other locations, no significant change was found with the results compared to the previous results.

Though the time of sampling at the observation hole on the sea side (3) on April 23 was previously announced as 1:19 PM, it has been corrected to 11:19 AM. We apologize for the mistake.

Please refer to our web page for the tritium analysis results and the correction made on the time of sampling.
http://www.tepco.co.jp/en/nu/fukushima-np/f1/smp/index-e.html

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

[Chloride concentration analysis results on May 2]

- Drain hole (northeast) of the underground reservoir No.1
Sampling performed at 5:30 AM on May 2
Chloride concentration: 12ppm

- Drain hole (southwest) of the underground reservoir No.1
Sampling performed at 5:30 AM on May 2
Chloride concentration: 7ppm

- Drain hole (northeast) of the underground reservoir No.2
Sampling performed at 5:40 AM on May 2
Chloride concentration: 9ppm

- Drain hole (southwest) of the underground reservoir No.2
Sampling performed at 5:40 AM on May 2
Chloride concentration: 7ppm

- Drain hole (northeast) of the underground reservoir No.3
Sampling performed at 5:50 AM on May 2
Chloride concentration: 8ppm

- Drain hole (southwest) of the underground reservoir No.3
Sampling performed at 5:50 AM on May 2
Chloride concentration: 4ppm

- Drain hole (northeast) of the underground reservoir No.4
Sampling performed at 6:00 AM on May 2
Chloride concentration: 9ppm

- Drain hole (southwest) of the underground reservoir No.4
Sampling performed at 6:00 AM on May 2
Chloride concentration: 8ppm

- Drain hole (northeast) of the underground reservoir No.5
Sampling performed at 6:15 AM on May 2
Chloride concentration: 8ppm

- Drain hole (southwest) of the underground reservoir No.5
Sampling performed at 6:15 AM on May 2
Chloride concentration: 7ppm

- Drain hole (northeast) of the underground reservoir No.6
Sampling performed at 6:20 AM on May 2
Chloride concentration: 12ppm

- Drain hole (southwest) of the underground reservoir No.6
Sampling performed at 6:20 AM on May 2
Chloride concentration: 8ppm

- Drain hole (northeast) of the underground reservoir No.7
Sampling performed at 6:10 AM on May 2
Chloride concentration: 5ppm

- Drain hole (southwest) of the underground reservoir No.7
Sampling performed at 6:10 AM on May 2
Chloride concentration: 7ppm

- Leakage detection hole (northeast) of the underground reservoir No.1
Sampling performed at 7:55 AM on May 2
Chloride concentration: 180ppm

- Leakage detection hole (southwest) of the underground reservoir No.1
Sampling performed at 8:10 AM on May 2
Chloride concentration: 5ppm

- Leakage detection hole (northeast) of the underground reservoir No.2
Sampling performed at 8:05 AM on May 2
Chloride concentration: 10ppm

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

- Leakage detection hole (northeast) of the underground reservoir No.3
Sampling performed at 8:15 AM on May 2
Chloride concentration: 9ppm

- Leakage detection hole (southwest) of the underground reservoir No.3
Sampling performed at 8:30 AM on May 2
Chloride concentration: 12ppm

- Leakage detection hole (northeast) of the underground reservoir No.4
Sampling performed at 8:40 AM on May 2
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 8:50 AM on May 2
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.