An endoscope has revealed low water and extremely high radiation inside unit 2 at the Fukushima Daiichi nuclear plant in Japan.
Among the news over the last week from the Tokyo Electric Power Co. nuclear plant blacked out following last year’s earthquake and tsunami:
72.9 Sv/h Recorded Inside Unit 2
On Monday, workers threaded an endoscope into unit 2 to gain a better understanding of its condition. According to a TEPCO release, they found water levels just 60 cm from the bottom of the primary containment vessel. The water temperature ranged from 48.5 C to 50 C.
The next day, they inserted a dosimeter into the PCV and recorded ambient dose rates of between 31.1 sieverts per hour and 72.9 Sv/h. (That is equivalent to 7,290 rem – exposure to which would be fatal within minutes). A TEPCO executive quoted by the Asahi Shimbun newspaper said the high dose was believed to be a consequence of melted fuel, and he acknowledged equipment would need to be developed that can withstand high radiation levels to clean up the unit.
TEPCO Proposes Reactor Mockup for Robot Development
On Wednesday, TEPCO and the Japanese government presented a proposal to build research facilities near the plant that would include a partial life-sized model of the reactors used at Fukushima. The model would be used to help researchers develop robots that can repair water leaks in high-dose areas. A research center would also be built to analyze waste from the plant’s decommissioning, including melted fuel, the Asahi reported.
120,000 Liters Leak from Water Treatment Hose
On Monday morning, a contractor found a sizable leak from a hose connected to the complex treatment system engineered to handle the water cooling reactors and flooding the plant’s lower floors. According to a TEPCO release, the hose transferred condensed water from desalination equipment to tanks; and the leak was promptly stopped when pumps were turned off. An estimated 120,000 liters (120 m3) of treated water containing radioactive material leaked. Of that, TEPCO estimated a maximum of 80 liters drained into the sea.