6 October, 2015
TEPCO Releases Decontaminated Groundwater Five Times into the Sea from Fukushima Daiichi
On October 1, the Tokyo Electric Power Co. (TEPCO) released a progress report on its decommissioning work at the Fukushima Daiichi Nuclear Power Plants.
At the specialized water facility treating contaminated groundwater pumped up from subdrains (a group of wells in the vicinity of the reactor and turbine buildings), the power company started the release of treated groundwater on September 14, carrying it out five times by September 28. So far, a total of 4,025 cubic meters of water has been released, including what was pumped up starting on September 3.
After the groundwater is treated at the facility, TEPCO and a third-party organization confirm that the concentrations of radioactive materials are below the operational targets before releasing it. The power company said that it would adhere to the operational targets and try to improve water quality in the port and prevent the sea from becoming contaminated.
On September 15, TECPO completed the installation of the three of the landside shielding walls that surround Units 1 to 4 on the mountain side. Those will be frozen first before the entire freezing takes place.
As for the remaining shielding wall facing the ocean, TEPCO installed steel sheet piles at the unfinished portion on September 22 to prevent contaminated groundwater from overflowing into the sea. After treating the joints to improve the wall’s water-tightness, it will reclaim the area inside the seaward shielding wall. The goal is to complete the wall by the end of October.
Meanwhile, TECPO began removing the roof panels of the reactor cover in July before removing spent fu
el from Unit 1. Five of the six panels had been removed by the end of last month. Dust monitoring and other readings at monitoring posts showed no significant changes. The sixth panel was removed on October 5 (see photo).