28 Juillet 2015
July 28, 2015
By HIROMI KUMAI/ Staff Writer
OKUMA, Fukushima Prefecture--Tokyo Electric Power Co. on July 28 started removing a canopy covering a damaged reactor building at the Fukushima No. 1 nuclear plant to prepare for the eventual extraction of spent nuclear fuel inside.
Around 7 a.m., workers using a giant crane lifted away the first of six canopy panels, each measuring 40 meters long and 7 meters wide, from the No. 1 reactor building.
The 30-minute removal of the panel left a large hole in the canopy through which steel beams on the damaged upper part of structure could be seen from above. Workers closely monitored radiation levels in the surrounding areas during the removal process.
The utility plans to remove the remaining five panels from next week.
The removal of the canopy will allow TEPCO to clear debris inside the building, possibly in the latter half of fiscal 2016. That process should pave the way for the removal of nuclear fuel rods from the spent fuel pool in the building.
Before removing the canopy panel, the utility sprayed the inside of the reactor building with liquid resin through holes drilled in the cover to prevent radioactive materials from being stirred up during the dismantling work.
TEPCO initially planned to start removing the canopy panels from the No. 1 reactor building in summer 2014, but the schedule was delayed because a large amount of radioactive substances was released into the environment when the utility removed debris from the No. 3 reactor building in August 2013.
Even after the anti-scattering resin was sprayed into the No. 1 reactor building in May, removal of the canopy panel was postponed by a problem inside the building.
TOKYO (Kyodo) -- The operator of the disaster-hit Fukushima Daiichi nuclear plant began Tuesday dismantling the cover shrouding the No. 1 reactor building, installed in the wake of the 2011 disaster to keep radioactive materials from dispersing.
Tokyo Electric Power Co. workers removed one of the six panels, each about 7 meters in width and about 42 meters in length, using a crane.
With the removal of the panel, the upper part of the reactor building, which was destroyed by a hydrogen explosion, became visible for the first time since last December, when part of the cover was temporarily removed.
The utility plans to complete the whole cover removal process in fiscal 2016, which begins next April, and clear debris and install equipment before beginning to take out the 392 spent fuel assemblies from the building's pool in fiscal 2020.
Takao Kikori, a senior nuclear safety official at the Fukushima prefectural government, called for care to be taken in conducting the dismantling work for the safety of local people.
The utility plans to remove the second panel in early August or later and complete the removal of all six panels by the end of this year. It also plans to later remove panels on the sides of the reactor building and install windbreaker sheets for debris clearing work.
The reactor building cover was installed in October 2011 as an emergency measure to keep radioactive dust from scattering. The utility initially planned to dismantle it in fiscal 2013 or 2014 but was forced to put off the work to take additional dust control and other measures.
Jul. 28, 2015 - Updated 00:38 UTC+2
The operator of the damaged nuclear power plant in Fukushima has begun work to remove the cover of the Number 1 reactor building, a step toward decommissioning the plant.
Workers are using a remote-controlled crane to remove one of the panels of the ceiling.
Tokyo Electric Power Company, or TEPCO, installed the cover after the 2011 accident to prevent the dispersal of radioactive materials. But the utility needs to remove it to allow the clearing of debris and removal of nuclear fuel in a spent fuel storage pool.
The operator plans to take several months to remove the 6 panels of the ceiling. It plans to then dismantle the cover while clearing debris.
The utility says it expects to complete the task around the winter of 2016.
The dismantling of the cover was originally due to start in July last year. But TEPCO delayed the operation after people living nearby expressed concerns over the possible spread of radioactive materials.
The utility postponed the work again in May this year as it found a problem with a device that controls the air flow in the building.
TEPCO has sprayed chemical agents on the debris in the building to prevent radioactive particles from being released into the air.
The operator says it will keep a closer watch on radiation levels and make information public during the work.