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 and April 1,
2011)
TEPCO continue measuring exhaust air from each building with filters for
a week and today detected the maximum of 9.8 x 10-9 Bq/cm3 of iodine 131
at the exhaust stacks of all units except Unit 3 and the exhaust vents of
service buildings of Unit 3, 5 and 6. 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 8.00KB)
Attachment-2: Detected location of trace amounts of radioactive materials
by regular monitoring in Kashiwazaki-Kariwa Nuclear Power
Station (PDF 35.6KB)
* 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.