Japan's disaster as bad as or worse than Chernobyl

VANCOUVER - The severity of Japan's Fukushima nuclear disaster may be as bad as or worse than Chernobyl, an American nuclear expert warned Sunday.

Arnold Gundersen, a former nuclear power industry executive, said it was clear to him within two days of the Japan earthquake and tsunami that "Fukushima was as bad as or worse than Chernobyl."

"We call that a level 7, which is as high as the scale goes," he said from his Vermont base via teleconference to delegates of a seminar entitled "The Fukushima Nuclear Disaster -- One Year Later."

Gundersen has publicly questioned the safety in a number of nuclear reactors around the globe and was an expert witness in the investigation of the Three Mile Island nuclear reactor disaster in the US state of Pennsylvania in 1979.

Gundersen, now chief engineer of the energy consulting company Fairewinds Associates, said he believed that Fukushima was 10 times worse than the 1986 Chernobyl meltdown in the former Soviet Union. Now it is in Ukraine.

Chernobyl was a single reactor running at about 7 percent capacity when ruptured, while Fukushima, about 275 km north of Tokyo, had three reactors running at 100 percent capacity and seven other reactors with spent fuel pools that were crippled, said Gundersen.

In addition, the battery-powered diesel generators along the ocean that cooled the reactors and were supposed to kick in during an emergency were destroyed, he added.

"Even if the diesels had survived (the quake and tsunami), there was no way to keep the (reactor) core cool. This is known as Loss of Ultimate Heat Sync (UHS), the most serious global issue relating to this incident, he said.

UHS is effectively the unlimited amount of water that is needed by nuclear power plants to cool down vital systems to contain them in the worst accidents.

Chernobyl stopped releasing radioactive material after about two weeks, said Gundersen, but this is not the case at Fukushima one year on.

If there were any positives to the Fukushima disaster, he said, the wind was mostly blowing out to sea at the time of the accident.

The bad news is large quantities of cesium 137, a radioactive material, has been found in abnormal amounts in the cedar trees of the surrounding mountains of the plant and "revolatalized into the atmosphere".

"Also, the cesium is being washed into rivers and the rivers, of course, are heading toward the ocean. But we are seeing contamination in freshwater fish as well as ocean fish as a result of all the run-off," he said.

"Large cesium deposits (are also being found) on the bottom of the river bed that gets picked up by weeds and seaweed in the ocean that then gets eaten by other fish and mollusks and work their way up the food chain,"  Gundersen added.

Although there have been no deaths related to the Fukushima meltdown to date, over the next 20 years there would be about 1 million additional cancers and other health problems from the accident, said Gundersen.

"The further you get away from Fukushima, the less people think their lives are affected," he said.

"But even in Tokyo most people think it is over and they survived it. But with the latency periods of these cancers it's going to pop up 20 years out and people will wonder where it came from," said Gundersen.