Sadly you are a product of the endless anti-nuclear hype. Radiation is invisible and sometimes dangerous, therefore it's scary! You actually have to run the numbers to understand the risks or lack thereof from Fukushima or other radiation spills.
The #1 fact you (and everyone else that thinks that Fukushima is a wide-ranging radiation poisoning disaster) need to absorb is that in the days of above-ground nuclear testing FAR more radioactive substances went into the Pacific Ocean than have from Fukushima. At Bikini Atoll between 1946 and 1958 the US detonated 67 nuclear weapons with a total explosive force of 108 megatons of TNT (that is, 108 MILLION TONS equivalent). ALL of them deposited radioactive materials in the Pacific. Even the smallest surface or underwater bursts deposited far more radioactive matter in the ocean than Fukushima. These types of weapons produce (among others) the exact same radioisotopes as the two most of concern from Fukushima.
The first thermonuclear shot, Mike is described thusly: "Experimental thermonuclear device, produced a crater 6,240 feet in diameter and 164 feet deep. Device itself weighed 164,000 lbs." Almost the entire device, and virtually all of the crater volume became highly radioactive fallout that entered the Pacific.
The biggest shot, Bravo, was a 15 megaton blast (it had been designed to be in the 4-8 MT range, but they were still learning) and had these results: "Largest nuclear test explosion conducted by the United States, produced a crater 6,000 feet in diameter and 240 feet deep. Expected yield 6 megatons (presumed range 4 to 8 megatons). Cloud top 114,000 feet." Again, most of the device and the entire crater volume ended up in the Pacific as highly radioactive material. This was the shot that deposited fallout on a Japanese fishing boat, a famous incident.
If this nuclear testing didn't leave the Pacific "a gigantic dead zone with no life", Fukushima certainly won't. Fukushima has probably resulted in (far) less than 0.1% of the radioactive material going into the ocean as the Marshall Islands test series.
We all remember the enormous impact all those nuclear explosions had on the Pacific fisheries, right? Oh yeah, there weren't any.
I hope this helps cool the vastly overblown hype surrounding Fukushima and it's radioactive output. How many people have died due to Fukushima radiation? Exactly zero. Say a prayer for the 17,000 that died during the earthquake and tsunami instead.
It is estimated that there are 180 + quintillion gallons of water in the pacific ocean. Just for chuckles and giggles, let’s say an Olympic size pool holds 684,000 gallons of water.
2 billion gallons of water would be about 1500 swimming pools. In the big picture and using Rush’s estimates for the gulf oil spill, this would be the equivalent of less than 1 drop of an eye dropper of ink in a full bathtub.
Note: This is not intended as a math lesson as the numbers are just estimates to show the sheer size of the ocean.