The operator of the Fukushima Daiichi nuclear power plant has begun dismantling the cover of a reactor building to remove debris as part of preparations for removing the nuclear fuel from a spent fuel storage pool.Tokyo Electric Power Company started the work on Wednesday at the No. 1 reactor building. The cover was installed after the 2011 accident to prevent the dispersal of radioactive materials.Using a remote-controlled crane, workers made holes in the ceiling and sprayed chemicals to prevent dust from spreading. The utility plans to make a total of 48 holes and to spray chemicals for about a week.Then, starting around October 30th, they will remove part of the ceiling to see whether any dust comes off.The operator hopes to begin full-scale dismantling of the cover in March and complete the task in about a year.It expects to start clearing the debris in 2016.The operator says it will monitor the possible spread of radioactive materials and post the data on its website.The dismantling of the cover was initially due to start in July of this year. But the utility deferred the work to come up with ways to ensure that radioactive materials do not spread.When debris from another reactor building was removed last year, some feared that radioactive materials might have dispersed and contaminated nearby rice paddies.The operator hopes to begin taking the fuel out of the storage pool at the No. 1 reactor building in fiscal 2017.