At the Unit 7 of the Station, the reactor and adjacent pools have been filled 
with water on Oct.8th.  At 12:00pm on Oct. 8th, a shift operator found water 
in the level gauge of pipes connected to the reactor well-liner. 
(Announced on Oct.9th, 2007)
Subsequently, we detected some radioactive materials (cobalt-60 and cesium-137) 
at around 10:27am on Oct.21th, by analyzing sample water taken from a minute 
crack on the reinforced concrete wall near the elevator of the 2nd floor of 
the reactor building (controlled area).  
The total amount of water leakage from yesterday amounted to about 6.5 liters 
with a radioactivity of 250Bq, which is equivalent to that of 30cm3 of radon spa.  
The water has been wiped off. 
We will examine the crack and investigate the cause of the water leakage. 
(Announced on Oct.21th, 2007)

(Water ooze from the reinforced concrete joint)
Today, at around 1:00pm, we found a very slight amount of water ooze on the 
floor concrete joint (about 1cm) of the 3rd floor of the reactor building 
and detected a slight amount of radioactive material (cobalt-60) in the water.  
The total amount of leakage was about 0.2 liters with a radioactivity of about 
0.8bq, which is equivalent to that of about 0.1cm3 of radon spa.  The water 
has been wiped off. 
The leakage is contained within the controlled area and hence there is no 
radioactive impact to the environment.  

(Water leakage into the flow glass of liner detection pipes)
As part of the survey of water leakage from the reactor well liner, we collected 
and analyzed water in the flow glasses of detection pipes of the reactor well-liner 
and the spent fuel pool liner, and found a slight amount of radioactive 
materials (cobalt-60 and cesium-137, etc.).  The amount of the water in the 
flow glasses is very small and is properly processed via the liquid waste 
treatment system, therefore it would not leak out from the pipes.

No abnormality indicating a leakage has been found in the water level of the 
spent fuel pool or in the level gauge of pipes connected to the pool liner.

(Our activities and observation)
Since a minute amount of leakages is continuing, we will continue our investigation 
on the causes and relevance with other events.  We will immediately make an 
announcement if any similar event were to be confirmed during the course of 
the investigation.

The leakages are contained within the controlled area and hence there is no 
radioactive impact to the environment.  

Furthermore, the crack in the concrete wall does not pose any safety issues 
to the plant since the relevant concrete wall does not require air- or water-tightness 
and since the crack is a minor one that does not affect the structural integrity 
of the building.