We conduct periodic measurement of exhaust air collected with filters for 
a week from each building of Kashiwazaki-Kariwa Nuclear Power Station. 
Since March 24, 2011, we have detected slightly above the minimum 
detectable amount of iodine 131 at the exhaust stacks of all units, the 
exhaust vents of service buildings of Unit 3, 5 and 6 and the exhaust 
stack of the auxiliary building of the Arahama-side. 
It is presumed that iodine 131 released into the air due to the accident 
at Fukushima Daiichi Nuclear Power Station was collected and detected, 
because no abnormality has been found in Kashiwazaki-Kariwa Nuclear Power 
Station.
The detected amount of iodine 131 does not have significant impact to the 
surrounding environment. (Previously announced on March 24, April 1 and 
April 19, 2011)

TEPCO continue measuring exhaust air from each building with filters for 
a week and detected the maximum of 9.8 x 10-9 Bq/cm3 of iodine 131 at the 
exhaust stacks of all Unit 2, 4, 5 and 6, the exhaust vents of service 
buildings of Unit 5 and the exhaust vents of auxiliary buildings at 
Arehama-side on April 26th. The detected amount of iodine 131 does not 
exceed 2.4 x 10-8 Bq/cm3 of iodine that had been already detected in the 
maximum. 
It is also similarly presumed that iodine 131 released into the air due to 
the accident at Fukushima Daiichi Nuclear Power Station was collected and 
detected, because iodine 131 was simultaneously detected at exhaust stacks 
of multiple units and no abnormality has been found in the status of units 
in operation and the density of iodine 131 in the water inside reactors.

Readings of monitoring posts and dust radiation monitors* are within the 
normal range and the detected amount of iodine 131 does not have 
environmental impact. The monitoring posts are located at boundary of the 
station site and the dust radiation monitors are located beside the 
monitoring posts.

Attachment-1:Monitoring result of iodine 131 in Kashiwazaki-Kariwa
             Nuclear Power Station(PDF 8.03KB)
Attachment-2:Detected location of trace amounts of radioactive materials 
             by regular monitoring in Kashiwazaki-Kariwa Nuclear Power 
             Station(PDF 35.5KB)

* Dust radiation monitor
   Measurement equipment to continuously collect the dust in the air in 
   the adjacent area of Power Station and measure radioactivity contained. 
   The equipments are installed nearby 3 monitoring posts.