The amount of Cesium-137 leaked from the Fukushima nuclear power plant could be worse than expected, a Japanese research team has concluded. They believe 50 percent more of the radioactive material could have escaped into the atmosphere and seawater.
The original estimate of 13,600 terabecquerels was made by Tokyo Electric Power Co. (TEPCO), the operator of the power station. However, a new report by Japanese researchers estimates that between 17,500 and 20,500 terabecquerels have been released, which is 50 percent higher than originally thought.
Michio Aoyama, a professor at Fukushima University’s Institute of Environmental Radioactivity who is part of the team, told Kyodo News that TEPCO is “underestimating” the amount of Cesium-137 that was released into the atmosphere and later fell into the sea.
Cesium-137 is a radioactive isotope produced by nuclear fission. However, it is problematic due to its ability to spread easily as it is highly soluble. It is also very harmful to humans and can cause cancer, while it has a half-life of around 30 years.
The team announced its findings at a conference in Vienna and it will come as another blow concerning their handling of the accident, which happened in 2011 after being triggered by a tsunami, following an earthquake in the Pacific Ocean off the Japanese coast.
Three weeks ago, the manager of the plant, Akira Ono, said attempts to plug the leaks of radioactive water had failed.
“It’s embarrassing to admit, but there are certain parts of the site where we don’t have full control,” Ono told Reuters. Last year, Japanese PM Shinzo Abe attempted to assure the world that the situation at the stricken nuclear power plant was under control.
The Fukushima plant contains radiation equivalent to 14,000 times the amount released in the atomic bomb attack on Hiroshima 68 years ago. The main task now is to try and limit the fallout from the disaster, with Aoyama saying, “the release of radioactive cesium-137 has a big impact on the ocean,” since the Fukushima nuclear complex is near the coast.
TEPCO has consistently faced contaminated water leaks at the Fukushima plant. Water has to be pumped over the facilities’ stricken reactors to keep them from overheating, but this process creates large quantities of contaminated water which has to be stored in tanks on the site.
Ono acknowledged to the media that in TEPCO’s rush to deal with the stricken facility following the earthquake-triggered tsunami in 2011, the company may have made mistakes.
“It may sound odd, but this is the bill we have to pay for what we have done in the past three years,” he said. “But we were pressed to build tanks in a rush and may have not paid enough attention to quality. We need to improve quality from here.”
TEPCO will have to improve the quality of the tanks so the plant can survive the next 30 to 40 years of the decommissioning process, Ono said.