For the last year and a half, workers at the Fukushima Daiichi nuclear power plant have been working to clear debris from atop the decimated reactor building. After an explosion ripped the building apart, twisted metal trusses, rubble and debris prevented clear access and visibility of the spent fuel pool.
By March of this year, workers had been able to remove large amounts of debris, but results have been spotty and during the course of the work there were multiple instances where operators moving cranes via remote control knocked debris into the spent fuel pool or dislodged other materials on the roof.
As of April 22nd, TEPCO has installed a cover over the Unit 3 spent fuel pool similar to Unit 4. The utility hopes that the new protection will aid workers in removing debris from the top of the reactor building, but the plant has repeatedly suffered mishaps which have shaken public confidence in the utility and regulators ability to manage a long-term decommissioning project.