Fukushima Daiichi NPS Prompt Report 2013

At around 7:40 AM today, a TEPCO employee found, via webcam, water overflowing from the top of a temporary notch tank for receiving groundwater pumped up at the well points and water collection pits that have been installed east of Units 1 and 2.

Accordingly, at around 7:43 AM, we stopped pumping up groundwater at the well points and water collection pits.

Regarding water that overflowed from the top of the temporary notch tank for receiving groundwater pumped up at the well points and water collection pits, we investigated the site. The water is remaining inside the dike covered with a protective sheet provided around the foot of the notch tank. Further, we have a line formed so as to enable water that overflows to return to the well points. For these reasons, we were able to rule out the possibility of the water that overflowed having seeped into the surrounding soil and the sea.

The overflow from the top of the temporary notch tank stopped as we stopped pumping up groundwater at the well points and water collection pits.

No significant change has been found in the monitoring post readings.