| Date |
Facility |
Brief Description of Event |
| Jan 15 |
Fukushima II-1 |
Reactor manually shutdown due to rupture of coolant flow measurement housing tube at jet pump. |
| Mar 4 |
Takahama-2 |
Power reduction due to steam leak into high pressure fead-water heater drain line. |
| Apr 5 |
Kashiwazaki-Kariwa-5 |
Control rod manual operation system failed due to integrated circuit abnormality. |
| Apr 19 |
Takahama-1 |
Reactor power manually lowered due to coolant leak caused by 2 heat exchange tube ruptures in high pressure feed water heater. |
| May 7 |
Fukushima II-2 |
Reactor manually shutdown due to failure of shutting check valve during residual heat removal system inpection. |
| May 23 |
Fugen |
Reactor manually shutdown due to tritium leak at helium circular system piping. |
| May 24 |
Fukushima I-6 |
Radioactivity leak found at fuel assembly during intermediate periodic inspection. |
| June 18 |
Kashiwazaki-Kariwa-6 |
Reactor manually shutdown due to coolant leak at reactor auxiliary cooling system valve. |
| July 6 |
Takahama-3 |
Damage to 17 steam generator tubes found during periodic inspection. |
| July 6 |
Fukushima II-3 |
Cracks found on core shroud lower ring during periodic inspection. |
| July 8 |
Kashiwazaki-Kariwa-5 |
Control rod manual operation system failed due to integrated circuit abnormality. |
| July 13 |
Kashiwazaki-Kariwa-5 |
Control rod manual operation system failed due to integrated circuit abnormality. |
| July 21 |
Kashiwazaki-Kariwa-7 |
Radioactivity leak found in fuel assembly. |
| July 27 |
Kashiwazaki-Kariwa-6 |
Control rod manual operation system failed due to integrated circuit abnormality. |
| Aug 10 |
Rokkasho repro. |
1.6 tons of coolant leak from pool coolant system heat exchanger outlet valve at spent fuel storage pool. |
| Sep 8 |
Ikata-2 |
145 cracks found on reactor core monitor housing tubes due to chloride induced stress corrosion cracking during periodic inspection. |
| Sep 10 |
Kashiwazaki-Kariwa-4 |
Ruptures and cracks found on regenerated heat exchanger tubes during periodic inspection. |
| Sep 19 |
Kashiwazaki-Kariwa-5 |
Control rod manual operation system failed due to integrated circuit abnormality. |
| Sep 25 |
Onagawa-2 |
Reactor manually shutdown due to coolant leak from degraded recirculation pump mechanical sealing. |
| Oct 31 |
Joyo |
Fire at maintenance building during sodium cleaning operation. |
| Nov 1 |
Fukushima II-2 |
Reactor automatically shutdown due to high signal of reactor neutron flux during reactor start up operation. |
| Nov 7 |
Hamaoka-1 |
Reactor manually shutdown due to pipe rupture in residual heat removal system steam condense mode line caused by detonation of radiolysis gases during start-up test at high pressure core injection system pump. |
| Nov 9 |
Hamaoka-1 |
Reactor coolant leak due to crack of stub tube welding attached to control rod drive mechanism housing. |
| Dec 10 |
Tokai II |
Reactor power reduced to 65 % of full capacity due to lowered reactor water level caused by abnormality of water flow control integrated circuit during maintenance in feed water pump system. |
| Dec 28 |
Rokkasho repro. |
Coolant leak from PWR spent fuel storage pool. |
