A Japanese robot was sent Friday into a damaged rector building for the first time to reduce the radiation exposure of workers, operator Tokyo Electric Power Co (TEPCO) said, DPA reported.
The unmanned robot "Quince" developed by a team of researchers at Chiba Institute of Technology entered the building of reactor 2 at the Fukushima Daiichi Nuclear Power Station to install equipment to measure water levels inside.
The operator made a Japanese robot work inside a reactor for the first time while US-made robots have been already used.
Since the plant was hit by the March 11 earthquake and resulting tsunami, it has leaked radiation.
The use of the robot inside a reactor came at a time when nine workers were found to have received a cumulative dose of radiation higher than the official limit of 250 millisieverts. TEPCO has been criticized for its lax safety management.
Meanwhile, TEPCO also said it had treated some 2,489 tons of highly radioactive water through a newly-installed water-treatment system at the plant by Thursday, Jiji Press reported.
The system is designed to remove radioactive substances from highly contaminated water flooding reactor buildings at the plant and use that water to cool the reactors.
TEPCO said the system can decontaminate some 1,200 tons per day, but the operator suspended the system soon after the start of its full operation a week ago.
During ongoing test runs over the past week, the system has processed radioactive water for only some 52 hours, Jiji said.
TEPCO has continued to inject water to cool reactors, the contaminated water has inundated the reactor buildings, which prevents workers from restoring key cooling functions.