Authorities battling the nuclear disaster at the Fukushima Daiichi power plant have doubled the number of workers on the site to 100 in an effort to continue cooling the three reactors and the spent fuel pools but have abandoned — at least temporarily — plans to use helicopters to dump water on the pools because of the radiation danger. Police may now use water cannons to spray the pools.
Workmen are also nearly finished stringing a new power line from the electrical grid to the power plant, which could ease the situation somewhat by providing a stable source of power for valves and controls at the plant and for pumps supplying water to the spent fuel pools.
It is too late for the electricity to do much good for the three endangered reactors, however, because their cooling systems all appear to have been damaged by the hydrogen explosions that have wracked the plants. Only external pumps can now be used for those reactors.
Officials are particularly concerned about reactor No. 3 because it is the only reactor at the facility that is fueled with what is known as a mixed oxide fuel. The pellets in mixed oxide fuel contain both plutonium and uranium. Plutonium is highly carcinogenic in small quantities, and its release into the environment would be very dangerous.
As the crisis at the power plant entered its sixth night, the situation appeared to be deteriorating. One sign was that the Japanese government increased the maximum radiation dose that workers could be exposed to from 100 millisieverts to 250 millisieverts, describing the move as "unavoidable due to the circumstances."
The good news is that the reactors should be undergoing a certain amount of cooling on their own. When an operating reactor is shut down, it continues to produce a large amount of heat, known as decay heat. Within the first week after a shutdown, that decay heat declines by about 50%, experts said, so that the reactors require less external cooling.
But can they keep it cool enough? If only they had the backup systems days ago, before the hydrogen explosions had damaged the cooling systems.
And who are the people doing this dangerous work?
Praise for 'heroes' working to avert Japan's nuclear catastrophe
(CNN) -- As the rest of the world waits with bated breath to see if Japan can avert a nuclear catastrophe, a small band of experts is putting their lives at risk to prevent the disaster.
Thousands of people living near the troubled Fukushima Daiichi nuclear power plant have been evacuated from their homes because of the risk of radiation leaks from reactors damaged by last week's devastating earthquake and tsunami.
But while most hurry in the opposite direction, about 180 plant workers are staying put -- despite the fact that doing so could result in serious illness or even death -- to battle the meltdown threat.
"The workers at this site are involved in a heroic endeavor," former U.S. Department of Energy Official Robert Alvarez told CNN.
"There is at least fragmentary evidence that in some places on this site there are life-threatening doses of radiation. I think they are doing enormously heroic work"
The workers left at the site are said to be highly trained and experienced nuclear operators, engineers and safety staff with highly specialized knowledge.
Professor Richard Wakeford, of the Dalton Nuclear Institute at the University of Manchester, said for many of them -- despite the highly unusual and potentially dangerous circumstances -- it will be just another day at the office.
"They see it as doing their job," he said. "The Japanese in particular are dedicated to duty, and they will see it as their duty to do what they are doing." [...]
Read the whole thing to see what these workers are facing. It's not as bad as the situation at Chernobyl was, but it's still fraught with many risks. Not just radiation, but hydrogen explosions as well.
I see they are now beginning to . They are working under very trying circumstances. Lets say our prayers that they can get through it, and that the situation can be brought under control.