First off, I agree with OUTLAW that it's not a good idea. Dilution is a very poor solution for pollution. It's not something you would plan to do ahead of time and say, "Hey, no biggie, it's a great big ocean out there."
But to help show just how big the numbers are, visualize it this way. (If I've messed up on my conversions or calcs, someone will surely jump in.)
Think of the 11,500 tons of slightly (sure wish we knew what "slightly" meant) radioactive water as a cube. How big? 71 feet per side. Now dump it in the ocean and assume it gets fairly well mixed within a short period of time. How big of a cube of ocean water would it take to dilute the 71 foot cube down to one part per million (ppm)? 2.7 cubic miles. That's not a very big piece of the Pacific Ocean. BTW, I'm not saying that there's anything magical about 1 ppm. It's just a fairly common reference point when looking at environmental pollution.
Please don't take what I say lightly either.
I've read the Awake! magazine for decades.
(Insert OUTLAW's dog here.)
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