Fukushima Update – October 2013
With the tsunami and loss of power, emergency control rods could not be lowered to stop the fissioning process of uranium in the fuel rods.
Three ongoing uncontrolled problems persist:
Each day, over 100,000 gallons of ground water from surrounding hills and mountains have become contaminated with radioactive nuclides. The Tokyo Electric Company has recently stated that most of this water has been draining into the Pacific Ocean. The resulting contamination has ben measured and verified by outside investigators.
143 tons of extremely radioactive spent fuel rods are in a cooling pool atop a six story very damaged reactor building. Some fires have occurred because of inadequate water for cooling could not be brought to the pool by helicopters or fire hoses. . The cooling has been stabilized thanks to employing a large machine with a long crane designed to deliver cement, imported from Germany. However, if the fragile building collapses and the rods tumble from the nest,, billions of curries of additional radiation would spread over the landscape.
The ultimate challenge is managing the source of the radiation. There are one hundred tons of highly radioactive uranium fuel in each of three reactors. Some cooling water is being pumped into and out of the reactors to lower the rate of fission. The outflow water is variably radioactive . It is being stored on site in very large tanks, waiting for a chemical process to clear the radioactive nuclides.
The fear of every expert, from the beginning, is that the huge radio active corium would breech through the steel walls of the reactor vessel, then through the six foot cement barrier and into the ground water below. This has now been verified as having happened at reactor number four.
In this case unfortunately, there is a large (“lake-size”) aquifer beneath all of the reactors. This water will be heavily contaminated. The extremely hot fuel reacts with water to make steam and to dissociate water molecules into an explosive mixture of hydrogen and oxygen. A large cavity is formed. With the high pressure, this gaseous mixture can penetrate the soil and find its way to the ground surface carrying radio active nuclides with it
The measured radio activity of the emitted gas is over 1000 REM, more than twice the lethal dose for any lingering onlooker. . A plant worker was asked what he would do on coming upon one of these steaming clefts in the ground. He responded, “I’d check the direction of the wind and run the other way."