13 Août 2015
August 12, 2015
The No. 1 reactor at the Sendai Nuclear Power Plant in Kagoshima Prefecture operated by Kyushu Electric Power Co. was reactivated on Aug. 11, in a hasty decision made without consideration for massive volcanic eruptions or evacuation drills for local residents.
The reactor, the first to be reactivated under new regulatory standards introduced in the wake of the Fukushima No. 1 nuclear plant crisis, was offline for approximately four years and three months. Its reactivation marked the end of a two-year stretch of no nuclear power generation in Japan, since the last nuclear reactors to be operated -- the No. 3 and No. 4 reactors at Kansai Electric Power Co.'s Oi Nuclear Power Plant in Fukui Prefecture -- went offline in September 2013.
At 10:30 a.m. on Aug. 11, Kyushu Electric pulled out the Sendai No. 1 reactor's control rods to start up the reactor, which reached criticality at 11 p.m. After confirming that the reactor's operation can safely be brought to a halt, on Aug. 14, it will begin generating and transmitting power. Output will be brought up to full capacity in stages, and commercial operations will begin in early September following Nuclear Regulation Authority (NRA) inspections.
The reactor had been stopped for regular inspections since May 2011, and concerns remain about possible problems resulting from deteriorating pipes and instruments. The NRA has called on Kyushu Electric to take all possible safety measures, the latter of which has said it will immediately notify the public of any problems with its facility.
At a press conference on Aug. 11, Chief Cabinet Secretary Yoshihide Suga said, "We will go forward with reactivation of other reactors once they meet the new criteria." Meanwhile, Economy, Trade and Industry Minister Yoichi Miyazawa said, "In the event of an accident, the central government will deal with it with responsibility."
Although the Sendai reactor met new regulatory criteria, problems remain. There are five caldera, shown to have caused massive eruptions in the past, in the neighboring areas. This is the largest number of any nuclear reactor in the country. Kyushu Electric argued during its safety assessment by the NRA that the possibility of a massive eruption while the reactor is in operation was sufficiently low, and indicated that it would stop the reactor and transport nuclear fuel out if any signs of an eruption were detected. Where the nuclear fuel would be transported, however, has not been decided.
Although the NRA determined that Kyushu Electric's measures were valid, many volcanologists have pointed out the difficulty of detecting signs of volcanic eruptions, since almost no observational records of massive eruptions exist. In response, the NRA decided to establish an expert panel that would advise the NRA on volcano-related measures, but the panel is not expected to meet -- at the earliest -- until this fall, when commercial operation of the Sendai No. 1 reactor is set to begin.
The reactor restart lacks consistency with Japan's nuclear fuel cycle as well. There are some 17,000 tons of spent nuclear fuel in storage pools at nuclear power plants nationwide, nearing full capacity of such storage facilities. The government plans to operate a nuclear reprocessing facility in Aomori Prefecture to deal with the issue of spent nuclear fuel, but the prospects of that happening are unclear. Storage pools at Genkai Nuclear Power Plant in Saga Prefecture, another facility that Kyushu Electric is intent on rebooting, are expected to fill up within around three years after its reactors are reactivated. A final disposal site for high-level radioactive waste that is generated when spent nuclear fuel is reprocessed has yet to be established.
Evacuation plans for residents in the event of an accident is not subject to NRA evaluation, and is left up to local municipal governments. In September 2014, the government approved an evacuation plan in the case of a Sendai plant incident drawn up by the Kagoshima Prefectural Government, but evacuation drills based on this plan have not yet been carried out.