Wall St. Journal, Aug 7, 2014 (emphasis added): [Shunichi Tanaka, chairman of the Nuclear Regulation Authority] said [Tepco] needs to get its priorities straight when it comes to work to decommission [...] Fukushima Daiichi [...] “The biggest risk is the trench water. Until that matter is addressed, it will be difficult to proceed with other decommissioning work,” [Tanaka] said on Wednesday at his weekly news conference. “It appears that they are getting off track,” he told reporters. Tepco has been trying to remove some 11,000 metric tons of water that contains dangerous radioactive materials such as uranium and plutonium from a trench that runs from the Fukushima Daiichi plant’s No.2 reactor building. […] “What if another tsunami hits the plant and the highly contaminated water in the trench is discharged… ?” Mr. Tanaka asked reporters.
NHK, July, 30, 2014: TEPCO initially planned to freeze radioactive wastewater that’s been flowing into underground utility tunnels [trenches] at the plant. It hoped the measure would prevent the wastewater from mixing with groundwater and flowing out to sea. But 3 months into the project, the water hasn’t frozen as planned.
Nuclear Engineering International, August 7, 2014: TEPCO has admitted that it has having problems with freezing contaminated water flowing in trenches [...] The water in the trenches is [...] coming into contact with nuclear material [...] because the water flows in and out of the trenches because of water pumping operations, it has proved ‘exceptionally difficult’ to freeze, TEPCO said. This was despite increasing the flow of coolant, adding ice and dry ice to the trench water [...]
Kyodo, Aug. 5, 2014: Tepco is racing to stop the buildup of radioactive cooling water in the trenches. […] Tepco inserted refrigeration rods in the trenches to try to freeze the water but abandoned the effort after more than three frustrating months. […] Though [Tepco has now put] 58 tons of ice in the trenches, the utility has “yet to see” whether it will work [...] The new method was introduced after an increasingly alarmed Nuclear Regulation Authority urged the company last month to take additional steps as soon as possible [...]
World Nuclear News, July 24, 2014: New approaches to removing the contaminated water from trenches [...] after attempts to freeze it failed. [...] The trenches contain highly-contaminated water that has flowed from the main power plant buildings [...] Tepco said that, despite the success of early experiments, “it has proved exceptionally difficult” to freeze the trench water. This, it said, is due to the constant flow of water into and out of the trench [...]
See also: TV: Nuclear waste “flowing out to sea” from underground tunnels at Fukushima — 950 Billion Bq/m³ of cesium in Unit 2 shaft next to ocean — 11,000 tons estimated in tunnels — Gov’t regulators ‘urgently assessing’ problems (VIDEO)
Published: August 7th, 2014 at 11:02 pm ET