Pacific Ocean, contaminated by leaking Fukushima!

I refer to the news report on July 23, of Radioactive wastewater from Fukushima power plant leaking into the Pacific ocean,  and I wonder if such contaminated water will eventually affect the lives of all those who live around the great ocean. Some questions need to be asked, and answers given:

• How far will the contaminated water travel from Fukushima? How dilute will the ocean need to be before the radiation will not pose any danger to those who are exposed directly and indirectly to it.
• Will the fish and other aquatic animals living in the Pacific Ocean be contaminated by it? Will eating of those fish cause cancer to the consumers? Will there be dangerous mutations of these animals exposed to the radiation?
  
• Can anything be done at all to prevent the contaminated water from reaching t he ocean? How long will the radiation 'stay' in the waters and affect our lives?

Are the various Governments trying to hide this fact from its citizens?