Cooling the Cores Keeps Them from Burning, but Creates Radioactive Water
The Japanese Atomic Energy Agency has joined with the U.S. to develop the necessary new technology, which it hopes to begin using within a decade. The Japanese agency calls this collaboration the "world's first" attempt at such technology, since a similar U.S. initiative to measure the melted core from the 1979 Three Mile Island accident failed.
As long as Fukushima's owner, the Tokyo Electric Power Company (TEPCO), keeps the three melted cores and the fuel rods in three other storage pools sufficiently submerged in cooling water, the radioactive material will not overheat, burn, and spew radioactive debris as far as wind or water might take it.
Watertight fuel pools are used effectively at nuclear power plants around the world, including Fukushima before the March 2011 earthquake and tsunami. Now the reactor structures are no longer watertight and TEPCO has pumped millions of gallons of fresh and "least contaminated" into the structures since then, and continues to do so.
Radioactive Water Is Dangerous, And It Has To Go Somewhere
Water used to cool nuclear fuel and waste becomes radioactive itself, as does the groundwater that infiltrates the structures. This radioactive water continues to reach the Pacific Ocean in varying quantities, as TEPCO attempts to keep it in check.
As of May 7, the Japan Times reported that TEPCO had installed 290 huge storage talks at Fukushima to hold more than 78 million gallons (290,000 tons) of radioactive water, with another 25 million gallons still uncollected. Fukushima is generating an estimated 100,000-plus gallons (400 tons) of radioactive water every day
TEPCO estimates that groundwater is entering the complex at a rate of at least 54,000 gallons per day. In May 2012, the Japanese government ordered TEPCO to build a wall deep into the ground around the plant to keep groundwater out, a plan that might become operational by early 2015.