Fukushima Daiichi NPS Prompt Report 2013

This is follow-up information on the latest situation concerning the detection of high densities of Tritium and Strontium in the observation hole at the east side of the Unit 1-4 Turbine Buildings of Fukushima Daiichi NPS.

Today (on July 2), as we have obtained measurement results for the γ nuclides and all-β from sampling performed yesterday (on July 1) in water of the groundwater observation holes No.1 and No. 2 and the groundwater observation hole No.1-1 (a new hole installed completely on June 27, on the east side (sea side) to the groundwater observation hole No.1) and in seawater inside the port, and measurement results for tritium in seawater sampled inside the port on June 25 and 26, we release those results.

No significant change was found with the γ nuclide and all-β densities in water of the groundwater observation holes No.1 and No.2 and in seawater inside the port, compared to the previous results. Water of the groundwater observation hole No.1-1 (on the east side (sea side) to the groundwater observation hole No.1) was found with nuclide densities about the same levels as the previous results, but was found with an all-β density of 4,300Bq/L, which increased from the previous result (3000Bq/L).

Upon obtaining the measurement results for tritium in these locations, we will release them likewise.

We are continuing to tackle this problem in such manners as to intensely bring forward implementation of contamination prevention measures such as foundation improvement work to the bank protection, and comprehensively intensify the monitoring by using the results of additional boring to drill additional locations, and the analyses results on seawater at such locations as the port interior and the water outlets.

<Groundwater observation hole No.1>
- Sampling on July 1:
Cesium-134 1.1Bq/L
Cesium-137 1.5Bq/L
All-β 1,300Bq/L
- Sampling on June 28 (previously announced):
Cesium-134 ND (0.40Bq/L)
Cesium-137 ND (0.43Bq/L)
All-β 1,400Bq/L

<Groundwater observation hole No.1-1>
- Sampling on July 1:
Cesium-134 ND (0.44Bq/L)
Cesium-137 0.98Bq/L
All-β 4,300Bq/L
- Sampling on June 28 (previously announced):
Cesium-134 ND (0.41Bq/L)
Cesium-137 ND (0.51Bq/L)
All-β 3,000Bq/L

<Groundwater observation hole No.2>
- Sampling on July 1:
Cesium-134 0.48Bq/L
Cesium-137 0.66Bq/L
All-β 260Bq/L
- Sampling on June 28 (previously announced):
Cesium-134 ND (0.40Bq/L)
Cesium-137 ND (0.48Bq/L)
All-β 170Bq/L

<Seawater in the Unit 1-4 water intake north side>
- Sampling on July 1:
Cesium-134 13Bq/L
Cesium-137 28Bq/L
All-β 420Bq/L
- Sampling on June 28 (previously announced):
Cesium-134 15Bq/L
Cesium-137 33Bq/L
All-β 230Bq/L

<Seawater between the water intakes of Units 1 and 2 (near the surface)>
- Sampling on July 1:
Cesium-134 4.9Bq/L
Cesium-137 11Bq/L
All-β 200Bq/L
- Sampling on June 28 (previously announced):
Cesium-134 8.5Bq/L
Cesium-137 19Bq/L
All-β 180Bq/L

<Seawater between the water intakes of Units 1 and 2 (near the bottom)>
- Sampling on July 1:
Cesium-134 5.7Bq/L
Cesium-137 14Bq/L
All-β 180Bq/L
- Sampling on June 28 (previously announced):
Cesium-134 7.5Bq/L
Cesium-137 17Bq/L
All-β 180Bq/L

For the past sampling results, please refer to the following page on our website.