The high levels of radiation that are being discussed are WITHIN the reactor containment. Of coarse they are high. Nobody ever enters the reactor containment. This is no surprise. These levels of radiation are NOT being released into the environment. Everybody needs to get the correct information.
The most reliable agency with respect to the Pacific Ocean is the National Oceanic and Atmospheric Agency (NOAA). To get an understanding of exactly what is being released from Fukushima into the ocean the reader is referred to the NOAA website. NOAA has modelled the radiation entering the Pacific Ocean from Fukushima using its sea tracers of Cesium-137. If you click on the link below, you will be taken to the NOAA website where you can run the model of radiation entering the ocean from the time just after the leak (April 2011 to April 2013). Running the model gives you a very good picture of the radiation that has been released and how ocean currents affect the distribution of radiation in the Pacific Ocean. NOAA Model
You can see, initially in April 2011, that there is a very concentrated release of Cesium-137 into the ocean. The darkest colours are the highest concentrations of Cs-137. You can see that release of radioactive contaminated water into the ocean continues until December 2011. However by December 31, 2011 you can see that there is no longer a release of highly contaminated water from the Japan mainland. This is evidenced by the lack of dark colours near Japan at this time. Therefore, Japan WAS successful at containing the disaster in the short-term.
However, there are still some major concerns. Despite best efforts, the Japanese still don't know how deep the highly radioactive melted core has advanced downward or if it has breached the outer containment structure. They are trying to detect the location of the melted core with robots and monitors that detect nutrinos but they have not succeeded yet. So they have no idea if the melted cores have passed through the containment.
They tried to freeze the area surrounding the plant to reduce the groundwater entering the radioactive contaminated area but they are still getting low level radioactive groundwater leaving the plant (this is evident in the NOAA model). They are collecting the most highly radioactive water and storing it on-site in tanks. There are thousands of gallons of highly radioactive water stored on-site and more is added every day.
However, there are still thousands of gallons of low level radiation leaking into the ocean daily, indicating that the ground freezing is not 100 % efficient at preventing groundwater from becoming contaminated.
If the highly radioactive core has melted through the containment vessel into the underlying rock then this still could be disastrous as deep groundwater could become highly contaminated. This deep groundwater may not be recoverable and still get into the ocean from greater depths.
The unkown location of the melted core is a serious problem and could pose a serious threat in the future, but it appears that Japan has succeeded in containing the most serious release.
Maddalena Environmental Inc.