Work to stabilize Japan’s stricken Fukushima nuclear plant started back up after officials suspended repair efforts because of a plume of black smoke seen coming from a reactor.
Japan’s nuclear safety authority said they took two employees to the hospital after they suffered from radiation exposure.
Earlier, more white smoke was coming from at least two of the site’s damaged reactors.
The battle to bring the plant under control and restart cooling systems almost two weeks after the massive earthquake is still critical — although officials said they have restored power to all the plant’s reactors.
Fears of radioactive contamination in Japan remain widespread. Levels of radiation considered above healthy limits were in Tokyo’s water supply causing a run on bottled water.
Japan’s chief cabinet secretary Yukio Edano explained what happened to the two workers suffering from exposure.
Edano said two of three men working together in the damaged Number 3 reactor’s turbine building slipped into water and did not realize they suffered exposure to high levels of radiation until they noticed a rash on their skin. They are suffering from beta ray burns.
Tokyo Electric Power Company Vice President Sakae Muto said the men were underground laying cable critical to restarting the cooling system for the reactor, which contains a mix of plutonium and uranium fuel.
Muto said all three of the workers suffered exposure of between 170 and 180 milliseverts of radiation. That is less than the government-set maximum of 250 millisieverts for workers at the plant.
There have been about 25 people injured at the nuclear plant since it began leaking radiation following damage on March 11 from the quake-triggered tsunami.
There is also fresh concern about the damaged Number 1 reactor, where pressure inside the reactor again increased. Crews are trying to maintain a delicate balance between spraying water on the radioactive fuel, which causes a rise in pressure, and reducing the water flow which could see temperatures increase to a dangerously high level.
Since the March 11 magnitude 9.0 earthquake, which triggered a destructive tsunami, the nuclear power complex has experienced a series of serious problems. These include hydrogen explosions in reactor buildings, radiation leaks, exposed and overheating fuel rods, damage reactor cores and shaking from powerful aftershocks.
James Symons, the director of the nuclear science division at the Lawrence Berkeley National Laboratory in California, said at this stage, the Fukushima disaster has more in common with the 1979 Three Mile Island partial meltdown in the United States than the 1986 Chernobyl catastrophe in Ukraine.
“All these things are different. But it’s closer. It’s certainly very unlike what happened at Chernobyl, where the entire reactor exploded, basically,” he said. “It’s certainly very serious, but – as far as we can tell – it’s also coming under control.”
Japan’s government says the detection of radioactive neutron beams 15 times near the plant following the destruction by the tsunami were natural events and there is no evidence any uranium and plutonium leaked from reactors.
A government spokesman in Tokyo, as well as Symons at the laboratory in Berkeley both reject assertions by some overseas in the industry that a critical nuclear reaction from a reactor or spent fuel rods likely emitted the neutron beams.
Japan’s government is now advising people beyond the 30-kilometer exclusion zone around the Fukushima plant to remain indoors. Officials said since the explosions, some infants theoretically may have accumulated 100 millisieverts of radiation in their thyroids.
Some scientists said those exposed to that total radiation dose should take potassium iodide, because an annual dose above 100 millisieverts could lead to an increased risk of cancer.
Japan’s science ministry said radiation levels detected in Tokyo have tripled, compared to those detected earlier in the week.
Compiled from wire reports.