The groundwater radiation level at the No. 2 reactor of the Fukushima No. 1 nuclear power plant is 17 times higher than it was a week ago, Tokyo Electric Power Co. announced Thursday.
The groundwater radiation level at the No. 2 reactor of the Fukushima No. 1 nuclear power plant is 17 times higher than it was a week ago, Tokyo Electric Power Co. announced Thursday.
There are concerns that highly contaminated water in the basement of the turbine building and in a tunnel outside the building has leaked into the environment.
Following instructions issued by the Nuclear and Industrial Safety Agency (NISA), the utility increased the number of radiation checks from once a week to three times a week to more closely monitor radiation levels of groundwater at the reactor.
On Wednesday, TEPCO collected and analyzed samples of water in wells built near the No. 1 through No. 6 reactors. The results show that the radiation level of iodine-131 in groundwater at the No. 2 reactor is 610 becquerels per cubic centimeter, a figure 17 times the value of 36 becquerels detected April 6.
The radiation level at the No. 1 reactor, which stood at 400 becquerels per cubic centimeter, has also increased by 6 times from a week earlier, showing a significant jump compared to the levels at other reactors.
High levels of radiation of 1,000 millisieverts or more per hour were detected in water in the tunnel outside reactor No. 2. It was determined the water had leaked into the sea through cracks found near an intake outlet.
The leak was plugged April 6, and while some of the water has been pumped out, most of it is still in the tunnel. TEPCO alluded to the possibility that this water, with its passage to the sea blocked, has seeped into the soil.
Radiation levels of groundwater at the other reactors, which either remain static or have dropped slightly, range from less than one becquerel to slightly more than 10 becquerels. These radiation levels at the other reactors raised the possibility that rainfall containing radiation has soaked into the ground.
Meanwhile, the U.S. Embassy in Tokyo said Thursday that the U.S. government has sent Japan five large stainless steel tanks for storing radiation-contaminated water and dedicated trailer trucks with special tanks for holding contaminated water.
The equipment is now on the way to Japan, the embassy said.
Storing and transporting radiation-contaminated water is essential to restoring reactor cooling systems at the Fukushima No. 1 nuclear plant. The U.S. government provided the tanks and trucks at the request of the Japanese government.
The United States has also shipped to Japan special robots and radiation-resistant cameras to videotape areas around the plant and create radiation dispersion maps, according to the embassy.