Top > Releases ･ Announcements > Fukushima Daiichi NPS Prompt Report > 2013 > Water Leak from the Underground Reservoirs in Fukushima Daiichi Nuclear Power Station (Follow-up Information No.61)
This is follow-up information regarding the water leak from the underground reservoirs at Fukushima Daiichi NPS.
The results of sampling performed in the drain holes of the underground reservoirs No.1-7 (at 14 locations) and the leakage detection holes of the underground reservoirs No.1-4 and 6 (sampling could not be performed in 2 out of 10 locations) yesterday (April 15) morning are as follows.
Compared to the analysis results announced in the follow-up report No.57, the all β density in the leakage detection hole (northeast) of the underground reservoir No.3 has increased while the all β density in the leakage detection hole (southwest) of the underground reservoir No.3 and the leakage detection hole (northeast) of the underground reservoir No.6 have decreased. No significant change was found in other locations.
The sampling analysis results obtained in the observation hole A8 newly installed near the underground reservoirs No.1-3 are also announced.
The all β density in the observation hole A8 (near the underground reservoirs No.1-3) was below the detection limit.
The water level, etc. of the underground reservoirs will continue to be intensively monitored.
The following analysis results are also available on our web page.
URL: http://www.tepco.co.jp/en/nu/fukushima-np/f1/smp/index-e.html
- Drain hole (northeast) of the underground reservoir No.1
Sampling performed at 5:30 AM on April 15
Chloride concentration: 14ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 3.0×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.5×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.7×10-2Bq/cm3)
All β: 1.6×101Bq/cm3
- Drain hole (southwest) of the underground reservoir No.1
Sampling performed at 5:30 AM on April 15
Chloride concentration: 5ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 3.3×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.7×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.9×10-2Bq/cm3)
All β: 1.2×10-1Bq/cm3
- Drain hole (northeast) of the underground reservoir No.2
Sampling performed at 5:50 AM on April 15
Chloride concentration: 9ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.7×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 4.8×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.9×10-2Bq/cm3)
All β: 4.1×101Bq/cm3
- Drain hole (southwest) of the underground reservoir No.2
Sampling performed at 5:50 AM on April 15
Chloride concentration: 6ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.7×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.2×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.7×10-2Bq/cm3)
All β: 3.0×10-1Bq/cm3
- Drain hole (northeast) of the underground reservoir No.3
Sampling performed at 6:10 AM on April 15
Chloride concentration: 6ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.3×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.3×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.6×10-2Bq/cm3)
All β: 1.2×10-1Bq/cm3
- Drain hole (southwest) of the underground reservoir No.3
Sampling performed at 6:10 AM on April 15
Chloride concentration: 4ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.5×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.4×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.5×10-2Bq/cm3)
All β: 3.0×10-1Bq/cm3
- Drain hole (northeast) of the underground reservoir No.4
Sampling performed at 6:20 AM on April 15
Chloride concentration: 8ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.3×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.8×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.8×10-2Bq/cm3)
All β: 5.0×10-2Bq/cm3
- Drain hole (southwest) of the underground reservoir No.4
Sampling performed at 6:20 AM on April 15
Chloride concentration: 8ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.7×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.0×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.6×10-2Bq/cm3)
All β: 8.9×10-2Bq/cm3
- Drain hole (northeast) of the underground reservoir No.5
Sampling performed at 7:20 AM on April 15
Chloride concentration: 5ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 3.1×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.1×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.7×10-2Bq/cm3)
All β: 6.3×10-1Bq/cm3
- Drain hole (southwest) of the underground reservoir No.5
Sampling performed at 7:20 AM on April 15
Chloride concentration: 6ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 3.2×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.0×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.6×10-2Bq/cm3)
All β: 6.2×10-2Bq/cm3 (Detection limit: 3.3×10-2Bq/cm3)
- Drain hole (northeast) of the underground reservoir No.6
Sampling performed at 7:30 AM on April 15
Chloride concentration: 10ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.2×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 4.9×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.8×10-2Bq/cm3)
All β: 3.0×10-2Bq/cm3
- Drain hole (southwest) of the underground reservoir No.6
Sampling performed at 7:30 AM on April 15
Chloride concentration: 8ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.5×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.3×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.9×10-2Bq/cm3)
All β: 6.3×10-2Bq/cm3
- Drain hole (northeast) of the underground reservoir No.7
Sampling performed at 7:40 AM on April 15
Chloride concentration: 5ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.5×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.2×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.5×10-2Bq/cm3)
All β: 4.1×10-2Bq/cm3
- Drain hole (southwest) of the underground reservoir No.7
Sampling performed at 7:40 AM on April 15
Chloride concentration: 9ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.6×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 4.8×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.9×10-2Bq/cm3)
All β: 3.8×10-2Bq/cm3
- Leakage detection hole (northeast) of the underground reservoir No.1
Sampling performed at 8:30 AM on April 15
Chloride concentration: 1280ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.1×10-1Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 2.6×10-1Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 1.3×10-1Bq/cm3)
Antimony 125: 2.9×101Bq/cm3 Ruthenium 106: 2.1×100Bq/cm3 All β: 3.4×104Bq/cm3
- Leakage detection hole (southwest) of the underground reservoir No.1
Sampling performed at 8:30 AM on April 15
Chloride concentration: 7ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.4×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.2×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.6×10-2Bq/cm3)
All β: 7.3×10-2Bq/cm3
- Leakage detection hole (northeast) of the underground reservoir No.2
Sampling performed at 8:40 AM on April 15
Chloride concentration: 90ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 6.0×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.8×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 7.5×10-2Bq/cm3)
All β: 4.6×103Bq/cm3
- Leakage detection hole (southwest) of the underground reservoir No.2
Sampling performed at 8:40 AM on April 15
Chloride concentration: 9ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.9×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.2×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.9×10-2Bq/cm3)
All β: 1.6×100Bq/cm3
- Leakage detection hole (northeast) of the underground reservoir No.3
Sampling performed at 8:55 AM on April 15
Chloride concentration: 8ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.7×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.5×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.7×10-2Bq/cm3)
All β: 6.5×10-1Bq/cm3
- Leakage detection hole (southwest) of the underground reservoir No.3
Sampling performed at 8:50 AM on April 15
Chloride concentration: 24ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 3.4×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.3×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 7.2×10-2Bq/cm3)
All β: 2.5×102Bq/cm3
- Leakage detection hole (northeast) of the underground reservoir No.4
Sampling performed at 9:10 AM on April 15
Chloride concentration: 9ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.4×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.1×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.8×10-2Bq/cm3)
All β: 8.5×10-1Bq/cm3
- 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 9:30 AM on April 15
Chloride concentration: 6ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.5×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.0×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.5×10-2Bq/cm3)
All β: 1.8×10-1Bq/cm3
- 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.
- Observation hole (near the underground reservoirs No.1-3) A8
Sampling performed at 11:06 AM on April 15
Chloride concentration: 9ppm
All β: Below the detection limit (Detection limit: 1.0×10-2Bq/cm3)
- Observation holes (near the underground reservoirs No.1-3) A11 and A18 are currently being drilled.
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