TEPCO testing new ways to stop radioactive pollution from Fukushima

March 31, 2011

Special resin designed to stop the spread of radiation from the stricken Fukushima No. 1 nuclear power plant is due to be tested by the facility’s operator, Tokyo Electric Power Co., as it searches for new ways to prevent the poisoning of land and sea near the plant.

The March 11 Great East Japan Earthquake and subsequent explosions scattered radioactive dust and rubble throughout the plant. If that dust gets into the atmosphere, it would interfere with work to restore the damaged reactors’ cooling mechanisms.

Substantial rainfall would increase the threat of the radioactive material flowing into the sea.

TEPCO officials were preparing March 31 to test a water-soluble synthetic resin for use as a dust suppressant. The resin is usually employed in landfills and other civil engineering projects.

Once sprayed on an area, the resin forms a film that TEPCO hopes will stop the spread of radioactive material. After it dries, the resin can prevent dust from spreading for six months to a year.

An official with a major water-processing company, which has been contacted by TEPCO officials, said the synthetic resins would be sprayed using hoses equipped with special nozzles.

A two-week test will be conducted at a number of areas at the Fukushima site, including a water-filled basement at the No. 4 reactor and an area to the north of the No. 5 and No. 6 reactors.

A sprinkler truck with a 2,000-liter capacity will be used to spray about 60,000 liters of a solution containing 15-percent synthetic resin.

Another measure being looked at is covering the damaged reactor buildings with specially coated canvas sheets.

TEPCO is also continuing to search for ways to deal with the large volume of radioactive water in the basements of the reactors’ turbine buildings and in trenches extending from the reactors.

Workers are trying to shift the contaminated water from condensers, condensate storage tanks and suppression pool storage tanks. If all of those tanks are filled, new containers will have to be found.

TEPCO officials say they are looking at using other containers within the plant’s grounds, but they may be forced to install temporary pools on the site if capacity is used up. Government officials are considering using empty tankers to take the contaminated water, but another possibility being actively considered is digging a reservoir.

That reservoir would have to have a waterproof lining to prevent radioactive water from leaking into the ground. It would probably have to be located away from the nuclear plant, because the high levels of radiation from the reservoir would make it difficult for workers trying to stabilize the reactors.

An official at the Nuclear Safety Commission of Japan said the cooling of the reactor cores “would not be done in a matter of months, but in a matter of years.”

Even in a normal situation, it takes between 20 and 30 years to close down and restore a nuclear plant site for other uses.

TEPCO officials said March 31 that water collected March 30 afternoon about 330 meters south of outlets from the Fukushima No. 1 plant had levels of iodine-131 that were 4,385 times the acceptable limit. Water collected the same day about 30 meters north of the outlets from the No. 5 and No. 6 reactors had iodine-131 levels of 1,425 times the acceptable level.

With contaminated water apparently continuously leaking from the facility, TEPCO officials are preparing to measure radiation levels 15 kilometers off the coast.

Work continued March 31 to remove the highly radioactive water in the basements of the turbine buildings.

Workers in the No. 1 reactor filled the condenser in that building and were looking for another tank to pump contaminated water into. The water level in the trench connected to the turbine building of the No. 1 reactor had dropped by 1 meter after pumping began on March 31.

At the No. 2 and No. 3 reactors, workers were trying to shift water from the condensers to other tanks, so contaminated water could be pumped into the condensers. That process was completed at the No. 3 reactor condenser on the morning of March 31.

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(c) The Asahi Shimbun

(c) The Asahi Shimbun

  • (c) The Asahi Shimbun

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