We periodically measure radioactivity of the seawater near the power 
station, environment samples such as the soil and pine needles as 
analyses of environment samples*1. We have detected slight amounts of 
radioactive materials such as cesium and iodine emitted into the air 
by the accident at Fukushima Daiichi Nuclear Power Station, however, 
they are below the level to give significant effects on the surroundings.
                   (Previously announced on April 13, May 13, and 26)

We measured and evaluated the samples of milk (law milk) collected on 
May 12 at 2pots near the power station as periodic sampling, and 
detected radioactive cesium 134 from the sample at 1 spot, and cesium 
137 from the samples at 2 spots. Both are small amounts, slightly
above detection limits.
(Please refer to the attachment for the measurement results)

Since we haven't found any abnormality in the operation status, 
exhaust stack monitors, or measurement results of seawater monitor, 
we assume the cesium was emitted into the air by the accident at 
Fukushima Daiichi Nuclear Power Station.

The total amount of radioactive cesium 134 and 137 at a single spot 
(0.046Bq/l) is approximately 1/4,000 of the intake limit*2 defined in 
the guideline to prevent nuclear disasters (200Bq/l), considerably low.

Even if you continue to take it in for one year, the radiation dose 
received from the total radioactive materials detected this time is 
approximately 0.0002 mSv/year. This is approximately 1/10,000 of 
radiation dose received from nature in a year (2.4 mSv), and 
is considerably lower than radiation dose received from X-ray at the 
chest (0.05 mSv, one time).

We will continue to measure radioactivity of the environment sample 
periodically.


*1: Analyses of the environment samples
 We periodically conduct surveys on radioactive materials contained 
such as in seawater near the power station, the soil, pine needles, 
and milk in accordance with the "Agreement regarding ensuring
security of the area surrounding the nuclear power station" 
(known as "Security Agreement").

*2: Intake limit defined by the guideline to prevent nuclear disasters
This is the index Nuclear Safety Commission of Japan stipulates in 
"Regarding countermeasures to prevent disasters at nuclear 
facilities" to limit the intake of radioactively contaminated food.

 
 
Appendix: Periodic measurement and the evaluation results of radioactive 
          materials at Kashiwazaki Kariwa Nuclear Power Station (PDF 29.4KB)