You homies on Van. Isl. are gonna' take a direct hit! Best not make any babies in the meanwhile.
OK … so the most shocking thing about that map is that there are regions of the Pacific Ocean with almost zero radioactivity.
Oh, wait, that map is trying to show radiation levels above the background.
So what is the (natural) background radiation in the ocean? Mmmmm … I'm no Radionucleotide Oceanographer, but these guys
http://www.umich.edu/~radinfo/introduction/natural.htm
say Potassium 40, the main source of radiation in the earth's crust and in your body, on average emits 11 Bq/L in the oceans. The chart shows readings in Bq/m3.
1m3 = 1000 L
So the ocean's background radiation from natural Potassium-40 alone is 11,000 Bq/m3. The entire Pacific ocean should be coloured a deeper red than the top end of their scale (10,000 Bq/m3).
The logaritmic scale is ridiculous, because the water in the yellow plume is between 1/100-1/1000th more radioactive than the ocean average. It is lower than the deviation in radioactivity from place to place in the ocean.
The WHO recommends radiation levels from natural radon gas in drinking water not exceed 300,000 Bq/m3 (300 Bq/l - or 300,000% more radiation than the Fuk-U-Finger of Radiation from Fukushima).