Fukushima Daiichi NPS Prompt Report 2013

This is follow-up information on the "water leak at a tank in the H4 area in Fukushima Daiichi Nuclear Power Station" found on August 19.

We would like to announce radioactivity density analysis results on seawater near the exit of the drainage channel of the south water outlet and water in the drainage channel B near Fureai Intersection (upstream in the drainage channel B), in the drainage channel C near the main gate (upstream in the drainage channel C), at the junction of the drainage channels B and C near the H4 area (previously referred to as "water of the side ditch in front of the core warehouse"), at 3 sampling points inside the drainage channel B, and at the drainage channel C OP. 30m exit (downstream of the junction of the drainage channels B and C), sampled yesterday (on September 2), as follows.

At the location near Fureai Intersection (B-0-1), the all-β density increased from 70Bq/L (in the sample taken on September 1) to 380Bq/L.

While this location is situated upstream of the tank area, no change was found in the densities at the locations downstream of the tank area. Therefore, we will closely keep track of analysis results.

With respect to the other locations, no remarkable change was found compared to the measurement results obtained from the sampling on September 1.

<Water in the drainage channel B near Fureai Intersection (sampled at 11:30 AM on September 2)>
Cesium-134: Below the detection limit value [the detection limit value: 20Bq/L (2.0×10^-2Bq/cm³)]
Cesium-137: 42Bq/L (4.2×10^-2Bq/cm³)]
All β: 380Bq/L (3.8×10^-1Bq/cm³)

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