Fukushima Daiichi NPS Prompt Report 2013

This is follow-up information on disconnection of a silt fence at a water intake for Unit 5 and 6 at Fukushima Daiichi NPS.

We would like to announce measurement results of sampling analyses performed in inner area of port, on the basis of the disconnection of the silt fence^* installed near the water intake for Unit 5 and 6.

< North of Unit 5-6 discharge channel >
Cesium-134: 1.7Bq/L
Cesium-137: 4.7Bq/L

< In front of Unit 6 intake canal >
Cesium-134: Below the detection limit value (the detection limit value: 2.1Bq/L)
Cesium-137: 3.0bq/L

(Reference: Fluctuating range in the past 6 months)
- North of Unit 5-6 discharge channel
Cesium-134: From below the detection limit value to 3.1 Bq/L
Cesium-137: From below the detection limit value to 7.5 Bq/L

- In front of Unit 6 intake canal
Cesium-134: From below the detection limit value to 2.4 Bq/L
Cesium-137: From below the detection limit value to 4.7 Bq/L

*The silt fence near the water intake for Unit 5 and 6 was installed for the purpose of preventing undersea sand in inner port area from flowing into the water intake for Unit 5 and 6 when water is taken into.

The measurement results of cesium 134 and 137 obtained at the north of Unit 5-6 discharge channel and in front of Unit 6 intake canal are within the fluctuating range of the measurement results obtained in the past 6 months. No influence by the disconnection of silt fence was found.

The disconnected silt fence will be replaced with a preliminary silt fence.

For the past sampling results, please refer to the following page on our website:
http://www.tepco.co.jp/en/nu/fukushima-np/f1/smp/index-e.html