VIENNA - The United Nations nuclear watchdog said Thursday the management of radioactive waste and contaminated water at the tsunami-crippled Fukushima No. 1 nuclear power plant could be improved despite “good progress” in cleaning up the site.
Tokyo Electric Power Co. said in February it had found a pool of highly contaminated water on the roof of a plant building and that it had probably leaked into the sea through a gutter when it rained.
The finding comes four years after a massive earthquake and tsunami caused three meltdowns at Tepco’s Fukushima No. 1 plant.
Some of the leaks have been dealt with, the International Atomic Energy Agency said. Efforts have included filling and covering of gaps, recovering contaminated soil and treating surfaces to prevent rainwater from leaking.
“While acknowledging these efforts, the IAEA experts encourage Tepco to continue to focus on finding any other sources contaminating the channels,” the agency said in a report released on Thursday.
Tepco’s decision to create a new branch 2014 that focuses on decontamination and decommissioning work at the plant was a good step toward defining responsibility for the cleanup more clearly, the IAEA said.
Still, there was room for improvement in how the body handles radioactive waste, for example by employing more complete waste characterization and packaging, it added.
The cleanup entity “could better employ long-term radioactive waste management principles (beyond the segregation, relocation and dose reduction/shielding currently performed),” the agency said.
“While recognizing the usefulness of the large number of water treatment systems deployed by Tepco for decontaminating and thereby ensuring highly radioactive water . . . is not inappropriately released . . ., the IAEA team also notes that currently not all of these systems are operating to their full design capacity and performance,” it added.
The IAEA will send a team to Japan this month to collect water samples from the sea near the Fukushima plant to help Japanese authorities with radioactive data collection and analysis.