http://ex-skf.blogspot.com/2013/08/tritium-in-perspective-if-rokkasho-ever.html
( Why would Japan even consider this ? )
While the amount of tritium released from Fukushima I Nuclear Power Plant since May 2011, 20 to 40 trillion becquerels which TEPCO finally told Nuclear Regulatory Authority on August 2, 2013, could be an order of magnitude lower than the amount if April 2011 were included, it would pale in comparison to what Rokkasho Reprocessing Plant in Aomori Prefecture would be releasing if (big IF) it ever becomes operational (the October 2013 target has been moved yet again).
According to Wikipedia on Rokkasho Reprocessing Plant (in Japanese):
http://ajw.asahi.com/article/0311disaster/fukushima/AJ201308030046
http://fukushima-diary.com/2013/08/column-the-urging-matter-of-fukushima-nuclear-plant-rising-groundwater-level/
( Why would Japan even consider this ? )
FRIDAY, AUGUST 2, 2013
Tritium in Perspective: If Rokkasho Ever Becomes Operational, It Will Release 18,000 Trillion Becquerels of Tritium into the Pacific Ocean PER YEAR
While the amount of tritium released from Fukushima I Nuclear Power Plant since May 2011, 20 to 40 trillion becquerels which TEPCO finally told Nuclear Regulatory Authority on August 2, 2013, could be an order of magnitude lower than the amount if April 2011 were included, it would pale in comparison to what Rokkasho Reprocessing Plant in Aomori Prefecture would be releasing if (big IF) it ever becomes operational (the October 2013 target has been moved yet again).
According to Wikipedia on Rokkasho Reprocessing Plant (in Japanese):
Amount of tritium to be released to the Pacific Ocean in liquid:
- 18,000 trillion becquerels (terabequerels) per year
Amount of tritium to be released into the atmosphere:
- 1,900 trillion becquerels (terabequerels) per year
Bioconcentration of tritium is supposed to be non-existent. But my search found this paper titled "Bioaccumulation of tritiated water in phytoplankton and trophic transfer of organically bound tritium to the blue mussel, Mytilus edulis." Jaeschke BC, Bradshaw C (Department of Systems Ecology, Stockholm University, SE-106 91 Stockholm, Sweden), Journal of Environmental Radioactivity, January 2013.
18,000 trillion becquerels per year into the ocean which has 829,000 trillion becquerels of tritium (according to UNSCEAR 2000 report quoted by TEPCO). Rokkasho would be adding over 2% of the existing amount to the ocean every single year. That's rather big for comfort.
Doubts cast over TEPCO's plan to block radioactive water at Fukushima plant
After nearly 30 months of failure, Tokyo Electric Power Co. is still providing little reason for confidence in its ability to deal with the radioactive water leaking at its Fukushima No. 1 nuclear plant.
The utility continues to face criticism for its delay in releasing vital information about conditions at the crippled plant. Fishermen and residents have lost patience over the many setbacks in TEPCO’s preparations to decommission the reactors.
And now, the Nuclear Regulation Authority is raising doubts about the utility’s latest plan: constructing underground walls to prevent the contaminated water from reaching the Pacific Ocean.
The immediate concern is radioactive water seeping along the seaward side of the No. 1 to No. 3 reactors and spilling into the sea.
TEPCO is currently solidifying soil with chemicals near a levee to prepare the ground for the walls.
But as work has progressed, the water level in observation wells has risen sharply to about 1 meter from the ground’s surface, apparently due to the accumulation of groundwater blocked from the ocean.
Due to limitations in construction methods, the walls can only be built with their tops at 1.8 meters beneath the surface. That means the water levels in the observation wells have already risen above the top edges.
If such a situation continues, the completed barriers will be unable to prevent the water from reaching the ocean. In addition, calculations show that if the water levels continue to rise at the current pace, contaminated water will flood the surface in about three weeks.
One huge problem facing TEPCO in dealing with the water is the maze of pits constructed beneath the Fukushima No. 1 plant site for pipes and power cables.
Immediately after the nuclear accident started in March 2011, an estimated 11,000 tons of highly radioactive water spilled into the pits under the No. 2 and No. 3 reactors. Some of that water is believed to have leaked further underground from cracks in the pits caused by the magnitude-9.0 Great East Japan Earthquake.
The reactor buildings are still connected to the pits, making it difficult to shut off the flow of water that becomes contaminated in the cooling process of the melted nuclear fuel that remains in the reactors.
A working group of the NRA held its first meeting on Aug. 2 regarding the leaking of contaminated water at the Fukushima plant.
The nuclear watchdog raised concerns that TEPCO’s plan to construct walls to block the leakage would be insufficient, and proposed pumping up the contaminated groundwater.
However, a TEPCO official said installing a pump would have to wait until late August because of the continuing construction work on the walls.
According to one calculation, about 100 tons of groundwater would have to be pumped up daily to prevent the water from leaking into the ocean. But the plant is running out of storage space for the contaminated water.
TEPCO officials remain confident that the completion of the walls in October will alleviate the water problem.
“There should be considerable improvement once we complete the additional measures,” Masayuki Ono, acting general manager of TEPCO’s Nuclear Power and Plant Siting Division, said at an Aug. 2 news conference.
TEPCO has also floated a plan to pump up groundwater flowing from the mountain before it enters the damaged reactor buildings and becomes contaminated. This “clean” water would be released into the ocean, thereby reducing the volume of contaminated water at the site.
However, local fishermen oppose the move in part because of their anger at the latest leaks of contaminated water into the ocean. They have also steadily lost trust in TEPCO.
Water contaminated with extremely high levels of radiation reached the ocean from the pits in the No. 2 and No. 3 reactors in April and May 2011.
TEPCO implemented measures to stop the leaks, and officials said they believed they had properly dealt with the problem at that time.
But in reality, contaminated water continued to flow into the ocean. TEPCO officials did not admit to that problem until July 22.
On Aug. 2, TEPCO officials said between 20 trillion and 40 trillion becquerels of radioactive tritium had leaked into the ocean. That is about 10 to 100 times the volume emitted over a one-year period of operating the nuclear plant.
“There is only a minor effect on the environment because it is about the same level as the upper limits of emission standards during operating periods,” a TEPCO official said.
However, TEPCO officials noted an increase in the volume of contaminated groundwater reaching the ocean since May, when concentrations of tritium in the water within the port at the Fukushima No. 1 plant began rising.
The utility estimated that between 20 trillion and 40 trillion becquerels will have entered the ocean by the end of July.
The company will make estimates of the flow of strontium, which has greater effects on the environment and tends to accumulate in human bones.
http://fukushima-diary.com/2013/08/column-the-urging-matter-of-fukushima-nuclear-plant-rising-groundwater-level/
[Column] The urgent matter of Fukushima nuclear plant -Rising groundwater level
Posted by Mochizuki on August 3rd, 2013 · No Comments
The groundwater level is coming up. Now this is the urgent matter. Here I would like to summarize the situation.
Where is it in the plant ?
It’s on the seaside of reactor 2. The area looks like a ledge coming out to the port between the water intakes of reactor 1 and reactor 2. On the other side of the sea, it has the building called “Reactor 2 turbine building”.
Why and how it started ?
Tepco thought contaminated groundwater is flowing to the sea from the area, and they injected chemical material underground. It is to stop groundwater like a “wall” on the coastal line.
Now the area is almost separated from the sea. However, the area has the constant supply of groundwater. Because it has no outlet, the water keeps accumulated.
How bad is it now ?
Currently the groundwater level comes up by 3~5cm everyday. It’s only 80~100cm deep underground. An the soonest, the water comes up to the ground on 8/19/2013.
What could happen ?
There are 3 possibilities.
1) Bearing power of the soil becomes too weak to support the buildings on/in the ground. – In the area, no main buildings are situated but it’s full of underground structures such as tunnels and shafts. They are full of extremely contaminated water. Also, if it becomes too weak, it would be very difficult to install the pump or new trench to remove water. The water is also contaminated.
2) Contaminated groundwater spread to other areas of the plant. – The area is 4m above the sea level. If the water comes up to the ground, the newly supplied groundwater would spread to the other areas because the area is already full. if it comes back to the mountain side, it would pressure reactor 2 turbine building. If it comes to the seaside of reactor 3, the same thing would be repeated there like Domino effect.
3) Land subsidence – This may be caused when they try to remove the groundwater. The sandstone bed lies underground with a few meters thickness. Now that it’s already full of groundwater, the layer can be taken out as they remove groundwater. The ground surface would have the land subsidence. It would cause the same result as (1) above, but also it would endanger the turbine building on the mountain side. At about 65m from the seaside, there is a cliff of 6m height. The building is standing on it. If the supporting ground has a subsidence, the soundness of the cliff will be affected.
Either way, Tepco doesn’t have time. I can’t understand know why they hurried to build the wall without anticipating any side effect.
[Column] Summary of Fukushima nuclear plant situation -past, present and future
Posted by Mochizuki on August 3rd, 2013 · No Comments
It has been over 2 years since 311.
We are slowly slipping down on the muddy slope.
Here I would like to summarize the Fukushima plant situation in the past, present, and future.
So far -4 reactors were crippled
There are 4 reactors in Fukushima. They are all crippled. Nuclear fuel are in 3 of them, but can’t get taken out because they are molten and scattered.
Tepco doesn’t even know where they are, and there is even no technology to know it. Just give it water. This is all they could do.
Chernobyl nuclear plant was packed in the sarcophagus. However, they can’t do it to Fukushima because they still need to give water to those 3 reactors and 4 spent fuel pools, where they stock used nuclear fuel under water.
Tepco is preparing to remove the spent fuel from reactor 1. Reactor 2 is very radioactive but they don’t even know what happened there. Reactor 2 is very mysterious.
Reactor 3 is completely crippled. Now they are picking up the steel beams on the top, which is the only thing they could do, but still nobody can even stand on there. Reactor 4 is empty but there is a spent fuel pool “hung” in the crippled building. They are installing the crane to pick up the fuel.
Now -Contaminated water is getting out of control
Because they need to keep giving water, they must treat more and more contaminated water. They circulate it but still it’s rapidly increasing.
The reason is because they must let groundwater in otherwise the coolant water goes out backward.
The plant area is limited, they are running out of the storage capacity. Tepco tried to purify and discharge it to the sea, but the purifying system deteriorated due to the contaminated water. It already started leaking on the test operation. Also, it can’t remove all kinds of radiation. Fishery’s agency doesn’t give Tepco their approval to discharge it.
However, the bottom line is the plant is entirely crippled. Water comes out from somewhere, and the water is severely contaminated.
Last month, Tepco admitted the contamination is traveling to the Pacific. In order to stop it, they built a wall on the coastal line.
and it’s turning out to be worst countermeasures. It doesn’t stop the water, plus it’s making the land literally swamped. The groundwater level, which is surely contaminated, is rapidly rising.
It will come up to the ground by mid August. Tepco is planning to pump up the water but they may end up losing the coastal area of Fukushima nuclear plant.
In a few years from now -Contaminated water will be the tyrant of the plant
Tepco may end up having to spend all the resource on controlling the water.
There are 4 sources of contaminated water -reactors, tanks, underground tunnels, and natural groundwater.
Reactor water – This is the most contaminated. Tepco doesn’t want to admit it’s leaking to the sea, but it’s highly likely to contain the worst nuclide “Plutonium”.
Tanks – The storage facility of the mixture of the coolant water and the ground water. Most of the tanks were not welded. Contaminated water deteriorates steel. It’s only the mater of time to scatter the stocked water all over the plant area, but it keeps increasing by over 400 tones a day.
Underground tunnels – Just after 311, extremely radioactive water accumulated in there and still retained. Tepco doesn’t even know the volume or the radioactive density. It doesn’t have the water shielding properties. The retained water is assumed to be leaking to the sea. Tepco plans to pump it up but because it’s connected to the buildings, contaminated water keeps coming in if they don’t shut them out. To cut it out from the buildings, they are trying to build the wall by freezing water but it hasn’t been actually examined in human history. It’s an attempt without any example.
Natural groundwater – Naturally 800~900 tones of groundwater travels from the mountain to the sea via Fukushima nuclear plant every single day. After 311, they are contaminated. Tepco is planning to stop it by installing underground wall but they are being defeated and the land is becoming a swamp.
Contaminated water will be the primary issue of Fukushima nuclear plant. Foreign media would “drop out” if they don’t check this point out.
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