What this suggests unfortunately is that radionuclides collected inthe sediments continue to be remobilized back into the food chain. This can continue for years and it suggests that it will becomenecessary to dredge the affected sea bottom. Since we are generallydealing with heavy metals, this could even be a practical solution.
This also implies that it remains largely localized and can be dealtwith.
The real problem of course is that our present solutions for handlingradioactive waste remain unsatisfactory. Reasonable solutions arepossible but naturally unproven.
I would dissolve the material at high temperature in a moltenrefractory to manufacture bricks. Those same bricks I would thenencase in a larger block to reduce the radiation effect to a safelevel. Best choices need to be determined but that is cheap andsimple. The blocks them selves could then be packed into a coal minewhich can be allowed to recompress. This surrounds the material witha natural sponge for errant atoms that might leak out.
That is about as practical a solution as I am able to devise. Onceit is set up and operating, special solutions can obviously be workedup also for irradiated hardware. If it gets down to it, we canoperate a coal mining front with simple concrete blocks containingirradiated hardware replacing the coal in the back space and simplyleaving no pillars.
Fishing for answersoff Fukushima
by Staff Writers
Cape Cod MA (SPX)Oct 31, 2012
WHOI senior scientist and marine chemist Ken Buesseler (foreground) checks a CTD sampler prior to deploying the instrument to collect data and water samples from the ocean off the coast of Fukushima, Japan. Credit: Ken Kostel, Woods Hole Oceanographic Institution.
http://www.terradaily.com/reports/Fishing_for_answers_off_Fukushima_999.html
Japan's"triple disaster," as it has become known, began on March11, 2011, and remains unprecedented in its scope and complexity. Tounderstand the lingering effects and potential public healthimplications of that chain of events, scientists are turning to adiverse and widespread sentinel in the world's ocean: fish.
Eventson March 11 began with a magnitude 9.0 earthquake, the fourthlargest ever recorded. The earthquake in turn spawned amassive 40-foot tsunami that inundated the northeast Japanese coastand resulted in an estimated 20,000 missing or dead. Finally, thewave caused catastrophic damage to the Fukushima Dai-ichi nuclearpower plant, resulting in the largest accidental release ofradiation to the ocean in history, 80 percent of which ended upin the Northwest Pacific Ocean.
Ina Perspectives article appearing in October 26, 2012, issue of thejournal Science, WHOI marine chemist Ken Buesseler analyzed data madepublicly available by the Japanese Ministry of Agriculture, Forestryand Fisheries (MAFF) on radiation levels in fish, shellfish andseaweed collected at ports and inland sites in and around FukushimaPrefecture. The picture he draws from the nearly 9,000 samplesdescribes the complex interplay between radionuclides released fromFukushima and the marine environment.
In it, Buesseler showsthat the vast majority of fish caught off the northeast coast ofJapan remain below limits for seafood consumption, even thoughthe Japanese government tightened those limits in April 2012.
Nevertheless, he alsofinds that the most highly contaminated fish continue to be caughtoff the coast of Fukushima Prefecture, as could be expected, andthat demersal, or bottom-dwelling fish, consistently show the highestlevel of contamination by a radioactive isotope of cesium from thedamaged nuclear power plant.
Healso points out that levels of contamination in almost allclassifications of fish are not declining, although notall types of fish are showing the same levels,and some are not showing any appreciable contamination.
As a result, Buesselerconcludes that there may be a continuing source of radionuclides intothe ocean, either in the form of low-level leaks from the reactorsite itself or contaminated sediment on the seafloor. In addition,the varying levels of contamination across fish types points tocomplex methods of uptake and release by different species, makingthe task of regulation and of communicating the reasons behinddecision-making to the fish-hungry Japanese public all the moredifficult.
"Topredict the how patterns of contamination will change over time willtake more than just studies of fish," said Buesseler, who led aninternationalresearch cruise in 2011 to study the spread ofradionuclides from Fukushima. "What we really need is a betterunderstanding of the sources and sinks of cesium and otherradionuclides that continue to drive what we're seeing in the oceanoff Fukushima."
Tohelp achieve this, Buesseler and his colleague Mitsuo Uematsu at theUniversity of Tokyo are organizing a scientific symposium in Tokyo onNovember 12 and 13 to present the most current findings availableabout how radionuclides from Fukushima Dai-ichi have affected theocean, marinelife, seafood, policy decisions, and media coverageto date.
The event will alsoinclude a free public colloquium in Tokyo on November 14 to helpspread information about the lessons learned to the broadest possibleaudience.
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