Thursday, April 21, 2011

Futile Water Use For Cooling at Fukushima

The Center remains livid with Fukushima Daiichi nuclear power plant owner Tepco and the Japanese government for not entombing the entire site.  The facility cannot be salvaged and a 500 foot tall sarcophagus should be used to permanently seal the site.  Absent this solution, radiation is being needlessly spewed into the air and ocean.  This mismanagement of the disaster is also destroying any possibility of a renaissance in building new nuclear power plants.  Seat the site.  Seal it now.

Overwhelmed by the large amount of radioactive water it had to deal with, Tepco released some of the relatively less-contaminated water into the ocean, sparking complaints from neighboring countries such as South Korea and China.

Workers at the plant are pumping water that is flooding the basement of the turbine building for reactor No. 2, which contains more than 30 million times Japan's allowable level of Cesium-137, a radioactive isotope. At the current rate of pumping, it would take more than 100 days to remove the water. That doesn't take into account additional water that could enter—either through continuing operations to cool the reactor with water, or from other sources—or government plans to eventually pick up the pace of pumping.

This timeframe is entirely unacceptable.  Seal the site.

Click on Image to Enlarge
Image Courtesy WSJ

Workers have reported only slight progress in removing radioactive water from parts of the complex surrounding its No. 2 reactor. Water in a trench that carries pipes from the turbine building's flooded basement contains radioactive iodine-131 at levels million of times Japan's legal limit, as well as extreme levels of a cesium isotope.  Water in the trench stands two and a half feet below the level at which the contaminated water would spill over at the ocean-side plant. That is not a very large safety margin.

Workers removed about 240 metric tons of water from the No. 2 reactor's basement by the end of the first day of pumping. At that rate, it would take more than 10 days to pump the equivalent of an Olympic-sized swimming pool. The estimated 25,000 metric tons of water in the No. 2 turbine building's basement alone is enough to fill 10 Olympic pools.  So where are the workers pumping the water to? 

Nuclear and Industrial Safety Agency (NISA) has noted that it is unclear whether a new water source is behind the slow progress. Officials Wednesday found rising water at a trench near the No. 3 reactor, which isn't as radioactive as that at No. 2.

At Reactor No. 6, one of the two units that have survived the March 11 earthquake and tsunami, workers Tuesday pumped 100 tons of water from the basement of the turbine building into the reactor's condenser unit. NISA said underground streams are a possible source. Before the crisis, streams beneath reactors No. 5 and 6 were pumped to divert water, a process that hasn't been conducted since the quake. (WSJ, 4/21/2011)

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