Environment

Pacific Ocean headed for normal radiation levels five years on from Fukushima

How to stop the spread of radioactive material from the Fukushima site is a problem that continues to plague the containment effort even now
How to stop the spread of radioactive material from the Fukushima site is a problem that continues to plague the containment effort even now
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How to stop the spread of radioactive material from the Fukushima site is a problem that continues to plague the containment effort even now
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How to stop the spread of radioactive material from the Fukushima site is a problem that continues to plague the containment effort even now

It's already been more than five years since three reactors melted down at Japan's Fukushima Daiichi Nuclear Power Plant, but the consequences of the disaster will linger for a while yet. Those monitoring the situation have received some good news, however, with scientists reporting that after suffering the largest ever release of radioactive material into the world's oceans, radiation levels across the Pacific are fast returning to normal.

How to stop the spread of radioactive material from the Fukushima site is a problem that continues to plague the containment effort even now. Tons of groundwater still flows into the reactor basements each day, with some of that then spilling into the sea after mixing with the radioactive material. Signs of contamination have been detected as far away as sites off the US West Coast.

Japan has sought to stem the bleeding by activating an underground ice wall around the facility, which is designed to seal away the nuclear waste. But according to researchers at Australia's Edith Cowan University (ECU), the material continues to seep out into the waters off Japan's east coast.

The ECU scientists partnered with international researchers as part of the Scientific Committee on Oceanic Research to conduct a major review assessing the radioactive caesium levels right across the Pacific, between Japan's coast to North America. Caesium lends itself particularly well to the task of monitoring radiation levels as it is a by-product of nuclear power and is highly soluble in water.

In the immediate aftermath of the nuclear disaster, radiation levels off the coast of Japan were tens of millions of times higher than normal. But after assessing data from 20 studies of radioactivity associated with the Fukushima disaster, the researchers are reporting that these levels are now fast returning to normal.

"Oceanic currents have dispersed the radioactive material across the Pacific Ocean as far away as North America,"says ECU Professor of Environmental Radiochemistry, Pere Masqué. "Radiation levels across the ocean are likely to return to levels associated with background nuclear weapon testing over the next four to five years. As an example, in 2011 about half of fish samples in coastal waters off Fukushima contained unsafe levels of radioactive material, however by 2015 that number had dropped to less than one per cent above the limit. However, the seafloor and harbor near the Fukushima plant are still highly contaminated and monitoring of radioactivity levels and sea life in that area must continue."

Source: Edith Cowan University

4 comments
Mirmillion
A little bit of hope for a contaminated Pacific? Scientists and naturalists are still pretending that the floor of the pacific is probably OK here in North America. Yet, the greatest sea star die-off in history is still going strong and unexplained mass deaths all the way up the food chain are being reported (and then explained away with nonsense and "official interpretation" one and the same really). No different than mercury but ever more harmful to body and environment. Environment Canada is pretty clear about the concept: "the solution to pollution is not dilution" but, for some reason Canada blindly followed along with the nuclear power lobby's idea that we should raise the maximum safe limit for this type of radiation (cesium) while quietly removing our coastal radiation monitoring stations - even in the wake of alarming increases detected in inner harbours and in kelp harvested on our shores. It is said that a dime-sized amount of cesium-137 can contaminate 800 acres of land and make it unsafe for human habitation for 100 years. Its a giant cover up.
prothopectore
Most “Background Radiation” Didn’t Exist Before Nuclear Weapons Testing and Nuclear Reactors Nuclear apologists also pretend that we get a higher exposure from background radiation (when we fly, for example) or x-rays then we get from nuclear accidents. In fact, there was exactly zero background radioactive cesium or iodine before above-ground nuclear testing and nuclear accidents started. Wikipedia provides some details on the distribution of cesium-137 due to human activities: Small amounts of caesium-134 and caesium-137 were released into the environment during nearly all nuclear weapon tests and some nuclear accidents, most notably the Chernobyl disaster. Caesium-137 is unique in that it is totally anthropogenic. Unlike most other radioisotopes, caesium-137 is not produced from its non-radioactive isotope, but from uranium. It did not occur in nature before nuclear weapons testing began. By observing the characteristic gamma rays emitted by this isotope, it is possible to determine whether the contents of a given sealed container were made before or after the advent of atomic bomb explosions. This procedure has been used by researchers to check the authenticity of certain rare wines, most notably the purported “Jefferson bottles”. As the EPA notes: Cesium-133 is the only naturally occurring isotope and is non-radioactive; all other isotopes, including cesium-137, are produced by human activity. Similarly, iodine-131 is not a naturally occurring isotope. As the Encyclopedia Britannica notes: The only naturally occurring isotope of iodine is stable iodine-127. An exceptionally useful radioactive isotope is iodine-131… (Fukushima has spewed much more radioactive cesium and iodine than Chernobyl. The amount of radioactive cesium released by Fukushima was some 20-30 times higher than initially admitted. Japanese experts say that Fukushima is currently releasing up to 93 billion becquerels of radioactive cesium into the ocean each day. And the cesium levels hitting the west coast of North America will keep increasing for several years. Fukushima is still spewing radiation into the environment, and the amount of radioactive fuel at Fukushima dwarfs Chernobyl.) As such, the concept of “background radiation” is largely a misnomer. Most of the radiation we encounter today – especially the most dangerous types – did not even exist in nature before we started tinkering with nuclear weapons and reactors. In a sense, we are all guinea pigs.
sgdeluxedoc
Just how much "hopefulness" does it take to also remove the increased levels from 5 years of contaminated water streaming in from the fuel rods that melted into the rock beneath the four affected reactors, or the contaminated water table, or the irradiated water gushing into the Pacific every single day? Perhaps they "hope" that "four out of five" neasurements will avoid hitting any "hot particles".. by pretending radiation instead "dissolves like sugar" in the ocean...
thaitoff
Some questions from the back of the class. The report speaks of "assessing the radioactive caesium levels", does this mean no other isotope activity was covered? If so, I would like to ask what happens to the rest of the ingredients in the MOX fuel used at Fukushima. Furthermore, given that radioactive isotopes can only be decreased in concentration through radioactive decay and secondly, such decay is modified in sea water, even if to-date never researched, it would be relevant to know the extent of the testing by “those monitoring the situation” and their exact coordinates so we can go and fish there!
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