No other industrial clean-up project is as big, complex and expensive as that of the Fukushima Daiichi nuclear power plant. 30 to 40 years are considered to be the minimum time required to successfully complete such projects, which are expected to cost hundreds of billions of dollars.
As recently as October 2014, Japan's nuclear energy operator Tokyo Electric Power Company (TEPCO) had to push back the restart date of the reactors by five years to 2025. TEPCO consultant Dale Klein, a former chairman of the US Nuclear Regulatory Commission and the chairman of a third-party panel commissioned by Tokyo Electric to oversee the reform of its nuclear division, said the restart is unlikely as long as the required technology has not been developed. The operator, for instance, will try to find the melted fuel - corium - in reactor 1 for the fist time in April with the help of a new robot.
Since the nuclear disaster, experts from the Vienna-based International Atomic Energy Agency (IAEA) had twice conducted on-site assessments of TEPCO's long-term closure plan. And the third visit of the 15-member IAEA team ended on Tuesday, February 17, with the experts expressing satisfaction with Japan's efforts. "Japan has made significant progress since our previous missions in 2013," the head of the delegation, Juan Carlos Lentijo, said in the IAEA's provisional report to the Japanese government.
The clean-up operation has led to a considerable reduction in radiation levels in many areas in the plant's vicinity. Lentijo also praised the complete recovery of the spent fuel from reactor 4 as well as the partial success achieved in the diversion of groundwater around the reactor building.
Delays in water clean-up
The IAEA team made more than a dozen suggestions for improvement but was also diplomatically cautious in formulating their recommendations: "The situation remains very complex and the extraction of the fuel represents a huge long-term challenge," stressed the Spanish IAEA expert.
The team recommended that TEPCO should develop an integrated plan for decommissioning the reactors as well as for waste management. The IAEA alluded to the fact that Japan has developed neither interim nor final disposal repositories for highly radioactive waste. Such facilities would, however, be needed for the radioactive waste coming from the decommissioning of Fukushima.
In addition, the IAEA is pushing for a sustainable solution to the water problem. Every day, Fukushima accumulates between 300 and 400 tons of contaminated ground and cooling water. A filter system that became operational in the fall cleans about 2,000 tons of water a day, ridding it of all radioactive isotopes except for tritium.
In May, two months later than planned, TEPCO wants to have cleaned all the water on site. The IAEA experts re-emphasized their earlier proposal to direct the cleaned water into the Pacific Ocean. "Of course, this would have to be accepted by all the parties involved and the general public," said Lentijo.
Fishermen, in particular, in the Fukushima region are opposed to any water dumping. Therefore, TEPCO wants to save the water for years to come on site. Hope remains for a new technical solution to dispose of tritium, so that fishermen will no longer reject the proposal.
The Japanese Nuclear Regulation Authority (NRA) also sees the introduction of water into the sea as the best solution. IAEA team leader Lentijo also supports this view: "Tritium has a very low level of toxicity and the potential impact on the safety of the people and the environment is very low."
The purified water in storage poses only a small risk, but slowly TEPCO will need more space for new tanks. Also the monitoring of reservoirs depletes resources. The discharge of treated cooling water into the surrounding area is a common practice with nuclear power plants, emphasized Lentijo.
Evacuees want to return
The IAEA team also called for better living conditions in the vicinity of the nuclear plant as well as for the safe return of evacuees. More than 72,500 people who used to live within the former 20-kilometer exclusion zone still live in container housing units.
In the meantime, the decontamination of streets and fields in the former exclusion zone continues. Many of the 7,500 inhabitants of the small town of Naraha - located 18 kilometers south of the plant - want to return to their homes, despite the fact that radiation there is still 20 times higher than the average 1 millisievert per year.
The railway line to Naraha which was damaged by the earthquake has been repaired and is currently in operation. A public bus also once again crosses the former restricted zone. In the rest of Japan, the fate of the evacuees seems to have already been forgotten. A survey conducted over the weekend by the "Asahi" newspaper found that 73 percent of respondents said their interest in the Fukushima disaster had lessened.