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 23), we obtained measurement results for the following substances in the following locations:
・γ nuclides and all-β in the groundwater observation hole No.3-1 (a sample taken on July 23), which has been newly installed.
・γ nuclides and all-β in the groundwater observation holes No.1, No.1-2, No.1-3, No.1-4, and No.2 (samples taken on July 22)
・Tritium in the groundwater observation holes No.1, No.1-2, No.1-3, No.1-4, No.2 and No.3 (samples taken on July 18 and 19)
・γ nuclides and all-β in seawater inside the port (other than seawater in the Unit 1-4 water intake north side and seawater between the water intakes of Units 1 and 2 (near the surface and near the bottom)) (samples taken on July 22)
・γ nuclides in the groundwater observation hole No.1-2 after filtering (a sample taken on July 22)

The measured γ nuclide and all-β radioactivity densities in the groundwater observation hole No.3-1 were at the same levels as those in the groundwater observation hole No.3.

With regards the measured densities in the groundwater observation hole No.1-3 (west of the groundwater observation hole No.1), all-β was detected at 150,000Bq/L, which is higher than the past highest density (120,000Bq/L in the sample taken on July 18).

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.3-1 (new)>
- Sampling on July 23:
Cesium-134 1.1Bq/L
Cesium-137 2.2Bq/L
All-β     ND

<Groundwater observation hole No.3> (previously announced)
- Sampling on July 18:
Cesium-134 1.2Bq/L
Cesium-137 3.1Bq/L
All-β     76Bq/L

<Groundwater observation hole No.1-3>
- Sampling on July 22:
Cesium-134 ND
Cesium-137 ND
All-β     150,000Bq/L

<Groundwater observation hole No.1-3> (previously announced)
- Sampling on July 18:
Cesium-134 ND
Cesium-137 0.53Bq/L
All-β     120,000Bq/L

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