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.79)
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 20) morning are as follows.
The results of sampling performed yesterday (April 20) in the observation holes of the underground reservoir (at 3 locations) are also provided below.
No significant change was found with the analysis results compared to the previous day (April 20).
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 5:35 AM on April 20
Chloride concentration: 16ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.9×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.5×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.8×10-2Bq/cm3)
All β: 2.3×101Bq/cm3
- Drain hole (southwest) of the underground reservoir No.1
Sampling performed at 5:30 AM on April 20
Chloride concentration: 6ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 3.0×10-2Bq/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: 3.1×10-2Bq/cm3
- Drain hole (northeast) of the underground reservoir No.2
Sampling performed at 5:45 AM on April 20
Chloride concentration: 10ppm (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: 6.5×10-2Bq/cm3)
All β: 1.7×101Bq/cm3
- Drain hole (southwest) of the underground reservoir No.2
Sampling performed at 5:40 AM on April 20
Chloride concentration: 7ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 3.0×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.3×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.7×10-2Bq/cm3)
All β: 2.7×10-1Bq/cm3
- Drain hole (northeast) of the underground reservoir No.3
Sampling performed at 5:50 AM on April 20
Chloride concentration: 8ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.8×10-2Bq/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: 2.0×10-1Bq/cm3
- Drain hole (southwest) of the underground reservoir No.3
Sampling performed at 5:50 AM on April 20
Chloride concentration: 8ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.4×10-2Bq/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: 1.1×100Bq/cm3
- Drain hole (northeast) of the underground reservoir No.4
Sampling performed at 6:00 AM on April 20
Chloride concentration: 9ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 3.0×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.1×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.6×10-2Bq/cm3)
All β: 4.8×10-2Bq/cm3
- Drain hole (southwest) of the underground reservoir No.4
Sampling performed at 5:55 AM on April 20
Chloride concentration: 8ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 3.0×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 4.8×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.7×10-2Bq/cm3)
All β: 4.3×10-2Bq/cm3
- Drain hole (northeast) of the underground reservoir No.5
Sampling performed at 6:30 AM on April 20
Chloride concentration: 13ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.1×10-2Bq/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: 3.1×10-1Bq/cm3
- Drain hole (southwest) of the underground reservoir No.5
Sampling performed at 6:25 AM on April 20
Chloride concentration: 8ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 3.0×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 4.8×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.7×10-2Bq/cm3)
All β: 8.0×10-2Bq/cm3
- Drain hole (northeast) of the underground reservoir No.6
Sampling performed at 6:20 AM on April 20
Chloride concentration: 11ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.4×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.3×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.6×10-2Bq/cm3)
All β: 5.2×10-2Bq/cm3
- Drain hole (southwest) of the underground reservoir No.6
Sampling performed at 6:15 AM on April 20
Chloride concentration: 9ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.8×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.3×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 7.1×10-2Bq/cm3)
All β: 2.3×10-1Bq/cm3
- Drain hole (northeast) of the underground reservoir No.7
Sampling performed at 6:35 AM on April 20
Chloride concentration: 7ppm (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: 6.6×10-2Bq/cm3)
All β: 8.7×10-2Bq/cm3
- Drain hole (southwest) of the underground reservoir No.7
Sampling performed at 6:40 AM on April 20
Chloride concentration: 8ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.8×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.1×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.6×10-2Bq/cm3)
All β: Below the detection limit (3.1×10-2Bq/cm3)
- Leakage detection hole (northeast) of the underground reservoir No.1
Sampling performed at 8:27 AM on April 20
Chloride concentration: 1150ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 1.8×10-1Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 2.4×10-1Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 1.2×10-1Bq/cm3)
Antimony 125: 2.9×101Bq/cm3
Ruthenium 106: 1.9×100Bq/cm3
All β: 3.5×104Bq/cm3
- Leakage detection hole (southwest) of the underground reservoir No.1
Sampling performed at 8:30 AM on April 20
Chloride concentration: 8ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.2×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.3×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.8×10-2Bq/cm3)
All β: 5.5×10-1Bq/cm3
- Leakage detection hole (northeast) of the underground reservoir No.2
Sampling performed at 8:42 AM on April 20
Chloride concentration: 18ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 3.3×10-2Bq/cm3)
Cesium 134: Below the detection limit (Detection limit: 5.2×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.8×10-2Bq/cm3)
All β: 6.2×102Bq/cm3
- Leakage detection hole (southwest) of the underground reservoir No.2
Sampling performed at 8:43 AM on April 20
Chloride concentration: 9ppm (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: 6.7×10-2Bq/cm3)
All β: 8.7×10-1Bq/cm3
- Leakage detection hole (northeast) of the underground reservoir No.3
Sampling performed at 8:53 AM on April 20
Chloride concentration: 10ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 2.6×10-2Bq/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: 1.0×100Bq/cm3
- Leakage detection hole (southwest) of the underground reservoir No.3
Sampling performed at 8:55 AM on April 20
Chloride concentration: 23ppm (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: 7.0×10-2Bq/cm3)
All β: 1.1×102Bq/cm3
- Leakage detection hole (northeast) of the underground reservoir No.4
Sampling performed at 9:09 AM on April 20
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: 5.0×10-2Bq/cm3)
Cesium 137: Below the detection limit (Detection limit: 6.6×10-2Bq/cm3)
All β: 2.6×10-1Bq/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 9:23 AM on April 20
Chloride concentration: 7ppm (Previously announced)
Iodine 131: Below the detection limit (Detection limit: 3.0×10-2Bq/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: 1.2×10-1Bq/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 12:46 PM on April 20
Chloride concentration: 8ppm
All β: Below the detection limit (Detection limit: 2.8×10-2Bq/cm3)
- Observation hole (near the underground reservoirs No.1-3) A11
Sampling performed at 3:01 PM on April 20
Chloride concentration: 30ppm
All β: Below the detection limit (Detection limit: 2.8×10-2Bq/cm3)
- Observation hole (near the underground reservoirs No.1-3) A18
Sampling performed at 11:14 AM on April 20
Chloride concentration: 8ppm
All β: Below the detection limit (Detection limit: 2.8×10-2Bq/cm3)
The observation holes (near the underground reservoirs No.1-3) A2, A3, A4, A5, A9, A10, A12, A13, A14, A15, A16 and A19 are currently being drilled.
The observation holes (near the underground reservoir No.6) B1, B2 and B3 are currently being drilled.
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