This story is from March 11, Six years after a giant tsunami destroyed the Fukushima nuclear power plant on Japan 's north-eastern coast efforts to get a grip over the lethal radiation originating from molten radioactive cores of three nuclear reactors are still in the preliminary stages. While radiation levels in the surrounding areas have come down, deadly radiation inside the buildings that housed the reactors is still preventing cleanup crews to even take a look at the situation.
Meanwhile , tons of contaminated water used for cooling the fuel rods has accumulated in tanks and scientists are unable to get rid of its toxic load. In January this year, a Toshiba-designed robot was sent in to the stricken reactor to survey the damage but it encountered radiation levels of sieverts, enough to fry it fast. A single dose of 10 sieverts is enough to kill a human within weeks. This robot was one in a series of devices designed by top firms to go into the basements of reactors where an estimated tons of molten radioactive fuel has burned through the massive concrete casings and lies smoldering.
The tsunami of March 11, was one of the deadliest ever and it knocked off the cooling systems of an ill-prepared nuclear plant complex at Fukushima. This led to a runaway heating up of highly radioactive fuel rods, explosions of radioactive gases and contamination of groundwater.
Some , people living in the vicinity of the complex were evacuated and most of them remain in camps away from the disaster site. The head of decommissioning at Tepco, Naohira Masuda said that decommissioning was making steadfast progress, radiation levels in the environs and the sea are down and about workers are able to work in the cleanup.
One tricky issue has been to control contamination of groundwater which naturally flows under the stricken plant and out to sea. A frozen wall has been built to prevent contamination and Masuda said that it had minimised the risk. The removal of radioactive Tritium, an isotope of hydrogen, from the stored water used to cool the fuel remains an intractable technical issue.
