Tokyo Electric Power Corporation (Tepco) says significant progress is being made on several fronts at the Fukushima-Daiichi nuclear power station, including the safe removal of nuclear fuel from the spent fuel pool at Unit 4.
Of the 202 fresh fuel and 1,331 spent fuel assemblies in the fuel pool when the removal process began in November 2013, 22 fresh fuel and 110 spent fuel assemblies have been removed, all without incident, Tepco said. The process will be completed by the end of 2014.
Unit 4 at Fukushima-Daiichi was shut down for a regular inspection when the plant was hit by an earthquake and tsunami in March 2011 and all spent fuel assemblies had been transferred to the spent fuel pool. The unused assemblies were being prepared to be inserted into the reactor when the disaster happened.
In its most recent progress report on remediation work being carried out at Fukushima-Daiichi, Tepco also said many steps were taken during the last quarter to improve the management of contaminated water, including improvements to storage tanks, some of which had been found to be leaking.
Dale Klein, chairman of the Nuclear Reform Monitoring Committee, said the progress report describes “two great milestones” for Fukushima-Daiichi: the very successful beginning of fuel removal work from Unit 4, and the adoption of a plan to concentrate responsibility for decommissioning in a new entity, the Decommissioning Company.
Mr Klein, former head of the US Nuclear Regulatory Commission, said Tepco is making “steady progress” in implementing the Nuclear Reform Plan, but he would like to see the pace of progress accelerate. “I am optimistic that this will happen as the achievements of the last two quarters generate momentum,” he said.
The progress report said Units 5 and 6 at Fukushima-Daiichi, which were undamaged by the earthquake and tsunami, are being converted into research centres to support decontamination efforts at the four damaged units.
Efforts intended to lead to the restart of Tepco’s Kashiwazaki Kariwa nuclear station are progressing, including a detailed review of a wide variety of safety features related to earthquakes, tsunamis, fire and flooding.
The seven-unit Kashiwazaki Kariwa station was not directly affected by the 2011 earthquake and tsunami, but it was struck by an earthquake in July 2007 leading to the automatic, safe shutdown of units 3, 4 and 7. Units 1, 5 and 6 were already shut down at the time of the earthquake for periodic inspections.
In November 2013, Japan’s nuclear regulator began examinations into whether units 6 and 7 at the station comply with new regulatory standards and are ready to be restarted.