Massive amounts of radiation-contaminated water that has been processed and stored in hundreds of tanks at the plant are hindering decommissioning work and pose a safety risk in case another massive quake or tsunami strikes.
“TEPCO needs to release the water — which contains radioactive tritium that is not removable but considered not harmful in small amounts — into the Pacific Ocean”, de lared Tokyo Electric Power Co.’s new Chairman Takashi Kawamura during an interview at the TEPCO headquarters in Tokyo on Thursday, July 13, 2017.
The method is favored by experts at the International Atomic Energy Agency and Japan’s Nuclear Regulation Authority as the only realistic option. Earlier, TEPCO had balked at calls by NRA chairman Shunichi Tanaka for controlled release of the water, now exceeding 770,000 metric tons, into the sea, fearing a public backlash.
Tepco’s intention to release more than 770,000 metric tons of tritiated water into the sea was relayed by many media, the Japan Times adding to the volume number of 770,000 metric tons, that it was contained in 580 tanks. The volume number is right, to be precise it concerns 777,647 metric tons of tritiated water, but the 580 tanks number is wrong.
Knowing that those tanks have a capacity of 1000 metric tons each, 777,647 metric tons can only be stored in 780 tanks and not in 580 tanks only.
Of course in that 777,647 metric tons, are not included the other 202,565 metric tons of only partially decontaminated water, in which Cesium and Strontium are been already filtered out but the other 62 radionuclides have not been yet filtered by the Multi-nuclides Removal System (ALPS). Those 202,565 metric tons stored in some additional 202 tanks more in the Storing Tank Area.
Bringing the total of contaminated water, Cesium/Strontium partially decontaminated water plus the 62 radionuclides decontaminated water (Tritiated water) to a total of 980,212 metric tons stored in 980 tanks.
Of course it is not question to release the partially decontaminated water (202,565 metric tons) into the sea, only the fully decontaminated water (all radionuclides removed to the exception of tritium), the tritiated water, the 777,647 metric tons.
On the Tepco Press Release on Jul 10,2017, Tepco indicates quite clearly the actual volume of the 2 types of water stored in those tanks. Knowing that all those tanks have a capacity of 1000 metric tons each, the maths are easy.
Some media along the way, I suspect the Japan Times AGAIN, added the 580 tanks number into its article, maybe a typo from 5 to 7, then the error was copied on and on by the other media.
It is sad to see professionnal media not capable to get their numbers right.
Since that July 13, 2017 declaration from Tepco’s new chairman, Tepco is now backpedaling, saying that they have not yet reached that decision, fearing a public backlash and the ire of the local fishermen.
The radioactive half-life of Tritium is 12,3 years, its radioactive full life is 123 years to 184,5 years. Once inside the body, tritium can lead to internal exposure. Its biological half-life of 10 days, full life 100 to 150 days.
Tepco Press Release July 10, 2017 Nuclear Power Station (310th Release) Nuclear Power Station (310th Release): http://www.tepco.co.jp/en/press/corp-com/release/betu17_e/images/170710e0201.pdf