Quote:
>But the US Nuclear Regulatory Commission and other experts have said the seepage will not affect areas beyond the sea directly off the coast of Fukushima Daiichi. "Even 300 tonnes [a day] — that's still going to be diluted to an almost undetectable level before it would get to any US territory," said the commission's information officer Scott Burnell.
You have to remember that this water isn't pure radioactivity, it's itself already a dilution.
>The volume of the Atlantic with its adjacent seas is 354,700,000 cubic kilometers
1 cubic kilometer is 1 000 000 000 000 liters, so 354,700,000 cubic kilometers is 354,700,000,000,000,000,000 l.
1 ton of water is 907 l water, and Fukushima leaks 450 tons a day, that's 408,150 l.
Divided and multiplied by 100 that's 1.3*10^(-13)%.
Keep in mind, as I said above, that this water itself is a dilution of radioactivity.