Japan needs to find or build storage facilities for 90 million cubic metres of radioactive waste in the wake of the nation\'s worst nuclear accident, dpa quoted local media as reporting Thursday. The volume is equivalent 72 domed baseball stadiums, Deputy Environment Minister Hideki Minamikawa was quoted as saying by local newspaper Fukushima Minpo. Since the Fukushima Daiichi Nuclear Power Station was struck by a magnitude-9 earthquake and tsunami on March 11, the plant has been leaking radioactive material into the environment. The government has been urged to start decontamination immediately in the north-eastern prefecture. But this requires Tokyo to find sites for the radioactive waste, Minamikawa said. The environment ministry said it would build sites to temporarily store radioactive waste generated by decontamination in Tokyo and six prefectures in eastern and northern Japan in addition to Fukushima. The waste consists of water, earth and rubble from the damaged buildings, which have been contaminated by radioactive material leaking from the reactor cores.