China’s Xinhua news agency reported today:
Tokyo Electric Power Co. (TEPCO) on Monday detected radiation levels in the building housing the faltering No. 1 reactor that far exceeded expected levels, reaching as high as 700 millisieverts per hour, the utility firm said.
This is problematic for repair work, as the Japanese yearly radiation exposure is 250 millisievers. Prior to the Fukushima disaster, the yearly allowable exposure was 100 millisieverts.
Actions taken by TEPCO may have resulted in the increased raidation levels:
TEPCO said that as 10 to 70 millisieverts per hour were detected in areas where workers would be expected to spend prolonged periods of time inside of the No. 1 reactor, restoration work is possible.
But the utility firm opened the main access points to the reactor and in doing do freely released 500 million becquerels of radioactive substances into the atmosphere, where it had gathered in the upper part of the reactor following a massive hydrogen explosion on March 12.
The initial exploratory readings may suggest the kinds of exposure repair workers may expect:
Seven TEPCO representatives and two from the nuclear agency entered the reactor in the early hours of Monday morning and measured radiation, working and safety conditions inside the reactor for roughly 30 minutes.
Following the reconnaissance mission, the nine people involved were exposed to radiation ranging from between levels of 2.7 millisieverts and 10.56 millisieverts, according the Nuclear and Industrial Safety Agency.
TEPCO plans to place radiation shielding in some areas:
The installation of such cooling equipment is likely to be hampered by high radiation, as the group found several radiation ” hot spots,” especially around pipes suspected to be clogged with highly radioactive material.
And, lest you think that the radiation problems are only inside the reactor building, Xinhua reported:
The nuclear agency and the Environment Ministry on Monday also began taking readings from highly contaminated rubble from the vicinity of the stricken No. 1 nuclear plant and remove some of the debris and bring it back to laboratories in Tokyo for further tests.
The radioactive rubble continues to emit radiation into the atmosphere, the ministry said.