nuclear-news

Long lasting radioactive contamination of the sea, from Fukushima disaster

for all the focus on land-based contamination, the continuing flood of radioactive materials into the ocean at Fukushima could have the most problematic long-term impacts. ….for centuries to come, at least some radioactive materials dumped into the sea at Fukushima will find their way into the creatures of the sea and the humans that depend on them. …… 

Is Fukushima Now Ten Chernobyls into the Sea? | Common Dreams, May 26, 2011  by Harvey Wasserman New readings show levels of radioisotopes found up to 30 kilometers offshore from the on-going crisis at Fukushima are ten times higher than those measured in the Baltic and Black Seas during Chernobyl.

“When it comes to the oceans, says Ken Buesseler, a chemical oceonographer at the Woods Hole Oceanographic Institution, “the impact of Fukushima exceeds Chernobyl.” 

for all the focus on land-based contamination, the continuing flood of radioactive materials into the ocean at Fukushima could have the most problematic long-term impacts.  Long-term studies of radiological impacts on the seas are few and far between.  Though some heavy isotopes may drop to the sea bottom, others could travel long distances through their lengthy half-lives.  Some also worry that those contaminants that do fall to the bottom could be washed back on land by future tsunamis.

Tokyo Electric has now admitted that on May 10-11, at least 250 tons of radioactive liquid leaked into the sea from a pit near the intake at Unit 3, whose fuel was spiked with plutonium.  According to the Japanese government, the leak contained about 100 times the annual allowable contamination.

About 500 tons leaked from Unit 2 from April 1 to April 6.  Other leaks have been steady and virtually impossible to trace.  “After Chernobyl, fallout was measured,” says Buesseler, “from as far afield as the north Pacific Ocean.”

A quarter-century later the international community is still trying to install a massive, hugely expensive containment structure to suppress further radiation releases in the wake of Chernobyl’s explosion.

Such a containment would be extremely difficult to  sustain at seaside Fukushima, which is still vulnerable to earthquakes and tsunamis.  To be of any real use, all six reactors and all seven spent fuel pools would have to be covered.
But avenues to the sea would also have to be contained.  Fukushima is much closer to the ocean than Chernobyl, so more intense contamination might be expected.  But the high radiation levels being measured indicate Fukushima’s most important impacts may be on marine life.

The US has ceased measuring contamination in Pacific seafood.  But for centuries to come, at least some radioactive materials dumped into the sea at Fukushima will find their way into the creatures of the sea and the humans that depend on them. ……
Is Fukushima Now Ten Chernobyls into the Sea? | Common Dreams

May 27, 2011 - Posted by Christina Macpherson | environment, Japan