Fukushima Daini is a four-unit boiling water reactor plant about 11km south of Fukushima Daiichi. The units entered commercial operation between 1982 and 1987. Although they experienced an emergency, the units were not damaged by the March 2011 earthquake and tsunami that caused the nuclear accident at the neighbouring Fukushima Daiichi plant. The four reactors have since been maintained in cold shutdown.
Tepco said its board of directors made the official decision at a meeting today to decommission Fukushima Daini. "The decision was made following a thorough consideration of various issues affecting both Fukushima Daiichi and Daini, including the securing of the necessary human resources, the safe decommissioning of the two power stations and the impact on our business," the company said in a statement. "We also took into account the wishes of local residents for decommissioning of the entire plant.
"Going forward, Tepco will explain to local communities how it plans to process the decommissioning work of Fukushima Daini in an easily understood way, aiming to proceed with their full understanding. Tepco will continue to make sincere efforts to safeguard the wellbeing of everyone in the region with regard to both Fukushima Daini and Fukushima Daiichi."
In an outline plan, Tepco said that decommissioning of nuclear power plants usually takes about 30 years to complete. "However, as the decommissioning of Fukushima Daiichi will be implemented at the same time, the allocation of human resources must be thoroughly considered," it added. "It is estimated it will take more than 40 years to complete decommissioning of all four units at Fukushima Daini."
The utility plans to remove all the used fuel stored at the Daini plant - which amounts to about 10,000 fuel assemblies - as quickly as possible, "at the latest by the end of the decommissioning process". Tepco is planning an on-site dry cask storage facility "to systematically progress fuel removal from the spent fuel pool".
Tepco said safety is its top priority and that it will implement the decommissioning work "steadily and in compliance with all relevant laws and regulations".
Tepco plans to offer local companies opportunities to participate in the decommissioning of the plant, including the procurement of materials and equipment, such as storage containers for dismantled materials, and will promote the effective reuse of materials. "In this way, Tepco will also strive to contribute to the revitalisation of the region."
The company will now develop a detailed decommissioning plan for Fukushima Daini, in conjunction with the decommissioning of Fukushima Daiichi, and will brief local communities throughout the process.
Tepco's decision to decommission the Daini plant along with the Daiichi plant means that all ten of its reactors in Fukushima prefecture will be scrapped.
The utility also owns the Kashiwazaki-Kariwa nuclear power plant in Niigata prefecture. It has applied to restart units 6 and 7 of that plant.