30 Novembre 2014
October 30, 2014
The Japanese government and Tokyo Electric Power Company have pushed back the schedule for decommissioning the Fukushima Daiichi nuclear power plant. NHK WORLD's Noriko Okada explains why.
TEPCO engineers started removing spent fuel from the storage pool in the NO.4 reactor building a year ago. They plan the same operation at all four damaged reactor buildings.
But the work was delayed by 6 months when engineers realized they had to spray chemicals inside the building to prevent radioactive particles from contaminating the environment
The complex engineering challenges continue to grow. The plan put together by TEPCO and the government calls for first removing all the onsite spent fuel before targeting fuel that has melted and solidified inside three reactor vessels.
The current timetable calls for the work to remove highly toxic debris from the reactor buildings to begin in 2020. But TEPCO executives now say this will start 5 years later...in 2025.
One reason for the delay is that engineers believe they'll have to build new facilities, and bring in cranes. They still have not located the debris inside the reactor buildings. Nor do they even know its state.
The government and TEPCO are developing robots to look inside the highly contaminated reactor buildings. They say they need the support of other countries such as the US and the UK.
What does all this mean? Officials initially said decommissioning the plant would take 30 to 40 years. But experts now say it will probably take longer.