The Kashiwazaki-Kariwa Nuclear Power Station Unit 7 (ABWR: 1,356MW) had been
shut down since the Niigata-Chuetsu-Oki Earthquake occurred on July 16, 2007.
On November 15, 2007, we have started the 8th regular maintenance.
After the Earthquake, we conducted inspections for equipments, soundness verification
works, restoration, and seismic reinforcement works. And we also conducted regular
inspections.
On May 9, 2009, we restarted the nuclear reactor. Subsequently, we resumed generation
on May 20, 2009, and the unit continued pre-conditioning operation. However, as
leaking assembly was confirmed, we shut down the reactor on September 26, 2009.
After conducted detailed inspections relating to leaking assembly, we replaced the
identified leaking assembly as well as about 100 other assemblies that were not
equipped with a debris filter with a new type of fuel assembly with a debris filter.*
We resumed generation on November 10, 2009, and the unit is continuing pre-conditioning
operation. METI's general integration inspection was completed at 4:45 p.m. on
December 28, 2009, and thus the unit resumed commercial operation.
We express our appreciation again for valuable comments, assistances and guidance
from local residents and many people after the Niigata-Chuetsu-Oki Earthquake.
We will continue to operate Unit 7 with safety as the first priority. We will
also strive to make a safe and disaster-tolerant nuclear power station including
other units.
* New type of fuel assembly with a debris filter
A fuel assembly equipped with the filtration function at its bottom in order to
further reduce the influence of foreign matter on the fuel.
(Reference) Operation Status of the Kashiwazaki-Kariwa Nuclear Power Station
Unit 1 (1,100MW) Regular maintenance
Unit 2 (1,100MW) Regular maintenance
Unit 3 (1,100MW) Regular maintenance
Unit 4 (1,100MW) Regular maintenance
Unit 5 (1,100MW) Regular maintenance
Unit 6 (1,356MW) Shut-down
Unit 7 (1,356MW) Operation
