Fuskushima radiation from 2011 is popping up again from sands and groundwater 97 kilometers away from the nuclear power plant site.
An aerial view of the power plant in the aftermath of the 2011 earthquake and tsunami [Photo by Reuters]
Six years ago, a 9.0 magnitude earthquake struck off the coast of Tohoku in Japan, followed by a massive 50-foot-tall tsunami. This resulted in a severe natural disaster that also triggered one of the worst nuclear disasters in history. Now, scientists studying the Fukushima Daichi nuclear power plant have found a new and unexpected source of radiation nearly a hundred kilometers away from the site of the disaster.
According to these new findings, radioactive cesium from the power plant has appeared in sands and brackish groundwater in surprising areas. The radioactive waste is being slowly released into the ocean, though researchers say that the material won't be much of a health concern—as long as no one is exposed to the affected waters, that is. However, this discovery does bring to light the unexpected effects of nuclear disasters.
A beach near Fukushima
Apparently, the new-found source of Fukushima radiation contains the highest concentration of the isotope cesium-137 outside the Fukushima Daiichi power plant. However, researchers couldn't be sure if the cesium-137 isotopes came from the plant, or were remnants of nuclear weapons testing in the 1950s and 1960s. Researchers also found the isotope cesium-134, which could only have come from the plant.
The researchers used one- to two-meter-long tubes to pump up groundwater and test how much radioactive material was in the area. Their findings showed that cesium levels were 10 times higher in sand and groundwater than the cesium levels in the waters of the plant's harbor. It's possible that the cesium got stuck in the sand during transport along the coast. When the tides rose, it brought salt into the groundwater. This caused the cesium to disengage from the sand and flow out to the sea with the tides.
Blocked entry into the Fukushima Daichi nuclear power plant [Photo by Masaaki Tanaka/Getty]
“Only time will slowly remove the cesium from the sands as it naturally decays away and is washed out by seawater,” says Virginie Sanial, one of the researchers.
This, as mentioned before, is an unexpected effect of the nuclear disaster. Though there is no cause for concern over public health in this context, we may not always be so lucky. There are 440 operational nuclear reactors all over the world, and about half of them are located along the coast. The findings of the study on the unexpected effects of the Fukushima Daiichi power plant accident will be important to keep in mind when it comes to monitoring nuclear power plants and possible nuclear disasters in the future.
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