TEPCO erects coastal wall around No.1 nuclear reactor

It’s been one step forward and two steps back for officials trying to restore the Fukushima Daiichi site. Although it will take decades to clean up the power plant, the Tokyo Electric Power Company (TEPCO) has finally completed erecting a coastal wall around the Fukushima No. 1 nuclear reactor.

The coastal wall spans 780-meters and is intended to decrease the amount of contaminated water that continues to flood the Pacific Ocean. A massive tsunami decimated the power plant in 2011. Since then, hundreds of tons of radioactive material have contaminated both the air and sea. (1)

Some regions of the wall descend 30 meters into the ground. TEPCO says the underground wall will decrease the amount of tainted water flowing into the Pacific Ocean from 400 tons a day to 10 tons a day.

Until Monday, approximately 400 tons of contaminated groundwater had been leaking from both sides of the building and spilling into the sea. Nearly 150 tons of underground water continues to flood the basement of the reactor everyday.(1)

Unstable equilibrium

Much of the water has been shot into the plant in an effort to keep the nuclear fuel cool. Some water stuck inside the building is a consequence of pressure exerted by higher underground water levels outside the power plant.

TEPCO has been storing contaminated water from the nuclear power plant. They finally received the consent of local fishermen to dump the tainted water into the sea after it had been decontaminated. This agreement put pressure on TEPCO to fill in the wall’s ten meter opening on Monday.

TEPCO states the wall will reduce the amount of radioactive cesium and strontium contaminating the Pacific Ocean by one-fortieth and reduce the amount of tritium contaminating the sea by one-fifteenth.

Plant workers finished sealing the gap in the coastal wall around 10:00 A.M. They drove nine 30-meter steel pipes into the ground and infused mortar to plug the gaps, which closed the wall and should thwart slightly contaminated water from flowing into the sea, according to TEPCO.(1)

Tests taken from water samples in the nearby ocean detected radioactive substances like cesium-137 and strontium-90. Scientists claim that the density levels are to low to be a threat to human health.(1)

Nevertheless, there are no safe levels of radiation. Constant exposure to radiation, even in small amounts, has an accumulative effect over time and can lead to a host of health problems. In fact, a recent groundbreaking study found that children inside the Fukushima Prefecture were 20 to 50 percent more at risk for thyroid cancer than children outside the Fukushima Prefecture.(2)

Reducing water flow

The constant flow of tainted water into the ocean has given local fisherman and the general public anxiety. Many countries have issued bans on seafood exported from the Fukushima site. TEPCO states that it will continue to measure the nearby ocean’s radioactive density over November.(1)

TEPCO is also in the process of completing a frozen ice wall in an effort to isolate the nuclear reactors. The wall is made of frozen soil and is intended to prevent groundwater from entering the four damaged reactors. Officials hope to have the ice wall completed by the end of the year, though no one is sure whether the ice wall will work on a large scale. They hope to have it complete by the end of the year.

In order to meet this goal, TEPCO wants to freeze the soil with coolant equipment that is already underground. The Nuclear Regulation Authority has yet to give the company permission on the grounds that freezing the soil could drastically change the underground water level around the plant. If the water level outside the plant is lower than the water level inside the plant, the tainted water could easily spill into the surrounding region.(1)

Sources include:

(1) JapanTimes.Co.Jp
(2) FukushimaWatch.com