Kyushu Electric Power Co. has halted the No. 1 reactor at its Sendai nuclear power plant in southwestern Japan after failing to implement required anti-terrorism measures within the set time frame. The plant's No. 2 reactor is due to be taken offline for the same reason on May 20.
The threats to nuclear power plants are not restricted to earthquakes and tsunamis. The United States' Nuclear Regulatory Commission compiled anti-terrorism measures in the wake of the 9/11 terrorist attacks. Japan similarly compiled new safety standards that went into effect in 2013.
The new standards in Japan envisage such threats as an airliner crashing into a nuclear reactor building. They require plants to have an emergency control room at least 100 meters away from the nuclear reactor building, along with cooling pumps, so that the operator can continue to cool the nuclear reactor even if the adjacent control room is damaged.
In the disaster at the Fukushima Daiichi Nuclear Power Station triggered by the Great East Japan Earthquake and tsunami, a total loss of power prevented the cooling of nuclear reactors, leading to core meltdowns. Hydrogen explosions then occurred, releasing a massive amount of radioactive materials.
This month, Toyoshi Fuketa, chairman of Japan's Nuclear Regulation Authority, reflected, "We must not forget our deep regrets from that time. The regulations are in place to prepare for risks that could only occur once in a thousand years."
Terrorist acts that could result in major nuclear disasters are risks that must be taken into consideration at nuclear plants. Under ordinary circumstances, response facilities should be ready to operate at the time the nuclear reactor is restarted.
Originally the deadline for completing the construction of response facilities was "within five years of the enforcement of new regulatory standards." However, this deadline was extended due to delays in the screening of nuclear reactors that was required before they could be restarted. The revised deadline was within five years of the authorization of construction plans, including safety and other measures, after each nuclear power plant was judged to comply with new safety standards introduced after the Fukushima nuclear disaster.
The first reactor to be restarted after the Fukushima nuclear disaster was the No. 1 reactor at the Sendai plant, and now it has reached that five-year deadline. Yet in spite of being granted a five-year period of grace, it failed to meet the requirements. It can't be helped if the operator is seen as having made light of safety.
So far nine nuclear reactors operated by the Kansai, Shikoku and Kyushu power companies have been restarted -- and all of them are facing delays in the construction of response facilities. Kansai Electric Power Co. is due to halt the No. 3 and No. 4 reactors at its Takahama nuclear power plant this year.
Power companies will not be able to avoid a loss of revenue from taking their reactors offline, and if they have to supplement power shortages with thermal power generation, then it will incur additional fuel costs. Furthermore, the costs for safety measures besides those to counter terrorism are only increasing.
The former catchphrase that "nuclear energy is a cheap and stable source of power" is no longer applicable.
There is no "finish line" when it comes to safety. The latest nuclear reactor suspension is surely the result of officials making light of this fundamental principle.