Japan's Nuclear Regulation Authority (NRA) on 7 November approved an extension of operations for the 40-year-old unit II reactor at Japan Atomic Power Co’s (JAPC’s) Tokai NPP in Ibaraki Prefecture. Tokai II's current operating licence is due to expire on 28 November. The 1,060MWe unit is the first boiling water reactor (BWR) to be approved for a 20-year lifetime extension. JAPC, which is owned by the country's main utilities, is required to complete safety upgrades, including construction of a 1.7km coastal levee, providing protection against a potential tsunami up to 17.1 metres high. Costs for safety measures at the plant are estimated at some JPY180 billion ($1.6 billion).
The plant is not expected to restart until the 2020s. JAPC will also need the approval of the Ibaraki prefectural government, as well as six local municipalities, including the village of Tokai. There is some local opposition. In October, Mayor Toru Umino of Naka, one of the six municipalities, announced his opposition to the extension. The city assembly of Mito, another municipality, adopted a resolution against the extension in June. After the Fukushima disaster, municipalities in close proximity to a nuclear plant were required to draw up an evacuation plan to respond to a nuclear emergency. However, only three of the 14 municipalities around Tokai II within that range have done so because of the difficulty of arranging transportation for such a large number of people.
Tokai II plant is the first NPP damaged by the March 2011 earthquake and tsunami to pass the NRA’s safety screening. The earthquake left the plant without an external power source, and the tsunami incapacitated one of its three emergency power generators. However, the plant managed to cool down its reactor over three and a half days after the disaster because the two other power generators remained operational.
Tokai II is the 15th power reactor approved for restart by NRA and the third BWR to be approved, the other two BWRs being units 6 and 7 at Tokyo Electric Power Co’s (Tepco’s) Kashiwazaki-Kariwa NPP in Niigata Prefecture. The reactors that melted down at Fukushima Daiichi were also BWRs. Nine reactors have restarted, all of them pressurised water reactors (PWRs), while the stigma of Fukushima still hangs over use of the older BWR technology. So far, three PWRs have been approved for extended operation under the post Fukushima regulations. These are Kansai Electric Power Company’s Takahama units 1 and 2 and Mihama 3 in Fukui Prefecture.
JAPC is in financial difficulty as none of its reactors has been online since the 2011 disaster. Tepco and Tohoku Electric Power Co, which receive electricity from Tokai II, have offered financial support. Tokai II began commercial operation in November 1978. Another reactor at the site, the 137MWe Tokai I Magnox unit, Japan's first commercial power reactor, was permanently shut down in 1998 and has been undergoing decommissioning since 2001.
