Highly radioactive water removal continues, water level drops by 1 cm

TOKYO, April 20 Kyodo -
The operator of the crippled Fukushima nuclear plant said Wednesday the level of highly radioactive water filling one of the underground tunnels at the site has dropped by 1 centimeter, a day after work to pump out the water started toward restoring the key cooling functions of the plant's troubled reactors.
But the level did not drop further in the morning even as workers continued to transfer the water building up around the No. 2 reactor turbine building of the coastal Fukushima Daiichi plant and the so-called trench connected to it, the government's nuclear agency said.
Hidehiko Nishiyama, the agency's spokesman, said he was not surprised by the outcome because the whole picture of the flow of water at the site is not completely clear, stressing the need to swiftly transfer 10,000 tons of the contaminated water into a storage facility as planned and to create a system to clean it.
The operation to remove part of the water in and around the No. 2 reactor turbine building, which is expected to continue until May, has been a priority to enable engineers to engage in restoration work and to prevent the water from further spilling into the Pacific Ocean.
While it is expected to take at least six months for the country's worst nuclear crisis to be resolved, sources said the same day that the government is expected to impose an order prohibiting people from entering areas within a 20-kilometer radius of the radiation-leaking plant.
As part of efforts to stably cool the troubled reactors, Tokyo Electric Power Co., the operator of the plant, plans to create a system by June to clean up the stored water to some extent. It is also hoping to eventually recycle some of the water so that it can be injected into the reactor core as coolant.
The reactors and spent nuclear fuel pools of the Nos. 1 to 4 units need to be periodically injected with water from outside because they lost their cooling functions after the March 11 quake and tsunami.
But the stopgap measure is creating vast pools of contaminated water inside the six-reactor nuclear complex, now estimated to total around 70,000 tons.
As of 7 a.m. Wednesday, the surface of the water filling up the vertical part of the trench connected to the No. 2 reactor turbine building was 81 cm below ground level, meaning that the water level dropped 1 cm since the water-removal work started.
But at 11 a.m., the water level did not change, Nishiyama of the Nuclear and Industrial Safety Agency told a press conference in the afternoon.
''This means that there may be some water flowing (toward the trench), although the possible route is not known,'' he added.
While workers focused on transferring the dangerous water around the No. 2 unit, which has an extremely high level of radiation exceeding 1,000 millisieverts per hour, the water level of another trench connected to the No. 3 reactor turbine building is edging up, the nuclear agency said.
The surface of the water as of 11 a.m. Wednesday was 108 cm below ground level, up 3 cm compared to the day before, according to Nishiyama.
The utility firm is also hoping to remove the contaminated water around the No. 3 reactor turbine building, but workers have not been able to empty an area inside the building that the firm wants to use to store some of the water.
''The condenser (where we want to store water) is already full and water appears to be flowing in. We don't know the reason,'' Nishiyama said in a press conference in the morning.
A condenser is an area where during normal operations steam created from the reactor is converted into water.
Tokyo Electric, known as TEPCO, also continued to inject nitrogen, an inert gas, into the primary vessel containing the No. 1 reactor to reduce the risk of further hydrogen explosions. The amount of nitrogen injected had totaled around 8,700 cubic meters by Wednesday evening.
With the crisis continuing to force many to evacuate from around the plant, TEPCO on Wednesday started distributing papers for provisional compensation claims at evacuation centers and elsewhere.
Around 50,000 households within 30 kilometers of the plant are eligible for the compensation. Each household composed of more than one member will receive 1 million yen, while single-person households will receive 750,000 yen each.