Groundwater level plunges near Fukushima reactor

The reason they didn’t divert the groundwater around Daiichi is because they need it to keep all the missing stuff cool & contained, relatively speaking …

“A sharp fall in the groundwater level just outside reactor buildings could cause contaminated water to leak from inside the buildings.”

 

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The operator of the Fukushima Daiichi nuclear power plant says the groundwater level briefly plummeted near a building that houses one of the crippled reactors.

Tokyo Electric Power Company, or TEPCO, says the fall was observed in a monitoring well about 11 meters southwest of the No.4 reactor building on Wednesday.

The utility says the groundwater level temporarily sank roughly 1 meter below the level of contaminated water inside the reactor building.

The firm says the groundwater rose above the usual level 23 minutes later.

A sharp fall in the groundwater level just outside reactor buildings could cause contaminated water to leak from inside the buildings.

TEPCO says it assessed the density of radioactive substances in the well water on Thursday and has confirmed no leak of contaminated water took place.

TEPCO stopped pumping out water from the well and reported the case to relevant local governments and the Nuclear Regulation Authority.

The company says it is conducting an investigation, suspecting that improvement work on another well 6 meters away may have caused the drop.

The utility publicized the drop on Thursday, one day after the phenomenon was recorded. The firm apologized for the delay in disclosure, saying it initially decided a problem had developed with the well’s water gauge as the water level in a nearby well remained unchanged.

The No.4 reactor building experienced a hydrogen explosion, but not a meltdown, during the 2011 accident.

https://www3.nhk.or.jp/nhkworld/en/news/20170804_06/

Ice wall at Fukushima plant to be examined

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Japanese government officials and the operator of the crippled Fukushima Daiichi nuclear plant say they plan to dig and check the ground around reactors. They want to see if an ice wall installed there is working as intended.

The underground ice wall is meant to prevent groundwater from getting into the damaged reactor buildings and becoming contaminated.

Tokyo Electric Power Company has been creating a 1.5 kilometer-long barrier of frozen earth since March. The ice wall is formed by circulating coolant in pipes buried around the reactor site.

Engineers believe that except for an area on the plant’s hillside, the freezing work has been completed.

Government and TEPCO officials have relied on thermometers in the ground to determine if the soil is frozen. But Japan’s nuclear regulator has urged them to more precisely check the conditions underground and the ice wall’s effectiveness.

This month, workers will dig several meters into the ground south of the Number 4 reactor to directly check the condition of the frozen wall. The area was chosen due to its relatively low radiation level.

Later this month, officials from a government task-force will inspect the site.

TEPCO’s decommissioning roadmap calls for most of the contaminated water to be removed from the reactor buildings in 2018. To achieve this, the ice wall needs to be completed and effectively preventing groundwater from flowing into the reactor buildings.

http://www3.nhk.or.jp/nhkworld/en/news/20161102_27/

Fukushima Untreated Bypass Groundwater Dumped into the sea

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Up to October 14, 2016, Tepco has discarded 137 times Fukushima Daiichi untreated groundwater from the bypass into the sea, all totalling now 222,816 tons (58,861,760 gallons).

That not including the 300+ tons a day of untreated groundwater flowing through the plant and into the ocean 24/7 for 5.6 years now.
http://www.tepco.co.jp/nu/fukushima-np/info/baypassold-j.html

Fukushima Daiichi Contaminated Groundwater Pouring into the Sea

 

Fukushima Daiichi Groundwater Rises from Typhoon N°16 Sept. 21, 2016

« Groundwater level rises in the aftermath of Typhoon 16, due to its heavy rain the groundwater now reaches now the surface.

It is unclear as whether or not the groundwater has been contaminated with radioactive material as it poured out into the sea, To be determined later, Tepco says. »

http://www.news24.jp/sp/articles/2016/09/21/07341567.html

 

Tepco pumping groundwater from Fukushima plant.

The operator of the Fukushima Daiichi nuclear power station says it is pumping groundwater from under the plant to prevent contaminated water from leaking into the adjacent port.

Tokyo Electric Power Company says the heavy rains brought by Typhoon Malakas have raised the underground water levels around the plant’s embankments.

TEPCO officials say they added pumps to prevent the groundwater from rising further. They say the water rose nearly to the surface shortly before 10 PM on Tuesday.

The officials say this has prevented rain from permeating the ground and increased the risk that the rainwater could become contaminated and flow into the port.
The utility says that while it is pumping the groundwater to prevent leakage, it will measure the radioactive substances in the water.
http://www3.nhk.or.jp/nhkworld/en/news/20160921_09/

Groundwater to be released into the sea on Monday

The operator of the Fukushima Daiichi nuclear plant plans to start releasing groundwater from around reactor buildings into the sea next Monday.

The government and the operator, Tokyo Electric Power Company, are to formally decide on the discharge date on Wednesday. The water has already been decontaminated.

Officials hope the move will help to curb the accumulation of radioactive wastewater in the reactor buildings. The contaminated water is increasing at a rate of 300 tons a day as the groundwater flows in.

The officials plan to first release some 4,000 tons of water pumped up from the wells around the buildings on a trial basis since August last year.

They say they will continue to pump up water and release it after removing radioactive materials.

Later this week, the utility also plans to resume the construction of steel walls along the coast to stop the groundwater seeping directly into the sea.

The construction work has been suspended until the release of the groundwater becomes possible. 

Source: NHK 

http://www3.nhk.or.jp/nhkworld/english/news/20150909_05.html

31,000,000 Bq/m3 of Strontium-90 measured at the nearest boring well to Reactor 2

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January 27, 2015

On 1/27/2015, Tepco announced they measured high density of Strontium-90 from groundwater in the seaside of Reactor 2.

It was 31,000,000 Bq/m3. The sampling point was the boring well, which is the closest to Reactor 2.

This is the highest density measured from this boring well, which is 10% more than the previous highest record.

The sampling date was last December. No Sr-90 data of January has been published.

http://www.tepco.co.jp/nu/fukushima-np/f1/smp/2015/images/2tb-east_15012701-j.pdf

Source: Fukushima Daiichi

http://fukushima-diary.com/2015/01/31000000-bqm3-strontium-90-measured-nearest-boring-well-reactor-2/

After failures, TEPCO to use special cement to prevent contaminated water leaks

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November 22, 2014

The operator of the crippled Fukushima nuclear plant plans to fill in trenches on the coastline in yet another attempt to prevent highly contaminated water from pouring into the sea.

Under the plan, approved by the Nuclear Regulation Authority on Nov. 21, Tokyo Electric Power Co. will inject a special cement mixture into the seaside trenches of the No. 2 and No. 3 reactors while pumping up radioactive water accumulating in them.

The special mixture does not absorb water so it can spread more easily along the bottom of the trenches, displacing the tainted water.

The new method will allow radioactive materials to remain in the surrounding soil, but TEPCO decided to employ the technique because it puts high priority on preventing massive amounts of highly contaminated water from leaking into the ocean.

This spring, TEPCO tried to stop the water influx at the trench for the No. 2 reactor by freezing the junction of the turbine building and the trench, but the operation was tough-going.

The company then attempted to stop the water inflow with a cement mixture, but was unable to do so completely.

Source: Asahi Shimbun

http://ajw.asahi.com/article/0311disaster/fukushima/AJ201411220029