Saturday 16 November 2013

Fukushima News - 11/15/2013

There seems to be absolutely no confirmation of the story below from a mainstream TV network. They do, however, identify why the operation should not happen.  The NHK report below,  is from about the morning of the 15th (GMT)

Japan postpones removal of Fukushima atomic fuel rods



15 October, 2013, 14:40 CET

The operators of the crippled Fukushima nuclear plant have postponed the extremely complicated and difficult task of removing damaged atomic rods.

New video footage from a robot has revealed new leaks within the damaged reactors meaning the rods now can’t be taken out as planned.

One of the fuel assemblies was damaged as far back as 1982 when it was mishandled during a transfer and is bent out of shape.

Kazuaki Matsui, the executive director of Japan’s Institute of Applied Energy said: “It’s very difficult to remove a spent rod because parts of the wall and the bottom of the reactor are all melted. We’ve never had to deal with this before so that adds to the complication.”

Meanwhile, decontamination workers say mismanagement is to blame for the delay of radiation removal work.

The inital plan called for the clean-up in the affected towns to be finished by March this year but the government now says the work will be delayed by as much as three years.


Fuel rod removal set to start at Fukushima plant
The operator of the Fukushima Daiichi nuclear power plant plans to take the first step in decommissioning the facility next week, more than 2 and a half years after its triple meltdown.

NHK,
Nov. 15, 2013 - Updated 10:33 UTC


Tokyo Electric Power Company, or TEPCO, said on Friday that workers will start removing nuclear fuel rod units from a storage pool at the plant's Number 4 reactor on Monday.

The pool holds more than 1,500 units, including some that are extremely radioactive and spent and others that are unused. The reactor holds the most units of any at the plant.

In March 2011, a hydrogen explosion severely damaged the building of the reactor. But unlike 3 other reactors at the plant, it did not suffer a meltdown as its pressure vessel was empty.

TEPCO officials say nuclear regulators and outside experts have found no problems with the firm's preparation to cover the damaged building and install a crane to remove the fuel.

Workers plan to transfer the units into a cask in the pool, use the crane to lift out the cask, and transfer the fuel to an outside storage pool about 100 meters away.

TEPCO has 2 casks that can each hold up to 22 units. Workers are to fill the first cask with less radioactive unused fuel. Removal of all the rods is expected to take until late next year.

Safety is a major concern in the project -- the first milestone in an unprecedented decommissioning process that could span 4 decades.

The reactor pool is still littered with small debris that could hamper smooth removal of the units.

The job will require extreme caution, as any damage to the fuel or casks could unleash high-level radiation.

If trouble occurs, workers' exposure could reach the safety limit, seriously setting back the removal process


To see video GO HERE



Gundersen: Fuel already “very close to going critical” at Unit 4
Must be extraordinarily careful about starting chain reaction



15 November, 2013

Fairewinds Chief Engineer Arnie Gundersen, Coast to Coast AM with John B. Wells, Nov. 9, 2013 (at 31:30 in):


Sources have told me — within Tokyo Electric — that they have no confidence that there’s any boron left between these fuel bundles. And they need boron to prevent the nuclear fuel from becoming a self-sustaining chain reaction, a criticality. So without boron in the plates — there are plates between these fuel bundles — but they got extraordinarily hot from not being cooled off the better part of a couple weeks, and they also were exposed to salt water. So that combination likely stripped out the boron. So the only thing Tokyo Electric can do is throw all sorts of boron into the water. Then pull the fuel. […]
I ran a division that built fuel racks, and these high density fuel racks like they have a Fuksuhima are very close to going critical anyway. […] Normally its .95, as high as .99, that means there’s a 1% margin before a self-sustaining chain reaction can occur. The problem there is that the fuel pool doesn’t have the ability to remove the heat if these nuclear fuel bundles turn back.— a criticality means they turn back on outside of the nuclear reactor. So they have to be extraordinarily careful that they don’t start a chain reaction in the fuel pool […] If they get close together you can cause a chain reaction, and what will happen then is the water will begin to boil violently. Hopefully Tokyo Electric is going to be monitoring this really closely and the first indication of water bubbling, they push the rods back in. The problem though is that the rack is distorted and as you pull it, you’re pulling way more friction than it was designed to handle. It’s a real problem.





Reactor no. 1 - 


Fukushima Watch: Remote-Controlled Boat Gives Glimpse of Damaged Reactor Building


WSJ,
15 November, 2013


The operator of the stricken Fukushima Daiichi nuclear power plant has for the first time confirmed that water is indeed leaking from the badly damaged No. 1 reactor vessel to the building that houses the unit by using a small remote-controlled boat.

While the upcoming removal of fuel rods from the No. 4 reactor building has received global attention in recent weeks, much more difficult tasks lay far ahead: Cleaning up the melted down No.1-3 reactors.

The job will be a huge challenge because these units are so highly contaminated that no one, even in a protective suit, can enter the building.

Given that almost all work in and around the Nos. 1-3 reactors would have to be done by remote controlled robots, the success in using the camera-equipped boat “is a big step forward,” said a spokesman for Tokyo Electric Power Co.

It has long been assumed that the No. 1 reactor vessel has been leaking since 400 metric tons of water is needed daily to keep the core from being exposed. But there had been no direct confirmation until the latest remote-controlled inspection.

The water in the reactor buildings, which becomes highly radioactive due to the high level of damage to the nuclear fuel, is currently being pumped out of the building and processed. Part is reused to cool the reactors, while the rest goes through another process to remove most radioactive materials and stored in tanks.

One of the difficulties in using robots in the complex decommissioning project is that one robot can generally undertake one specific task. Since there are numerous challenges, each step may require development of a new technology.

For example, Tepco plans to search the off-limits No. 2 and No. 3 reactor buildings, but the spokesman said the company is not sure if the same boat can do the job.

The Japanese government has so far provided about ¥94 billion ($939 million) for development of new decommissioning technologies including remote-controlled robots. The current boat was made by Hitachi Ltd., one of the makers of the Daiichi plant’s reactors.

There are many technologies not yet developed,” said Lake Barrett, a U.S.-based nuclear consultant who was the senior regulatory official in charge of the cleanup of the Three Mile Island nuclear plant in Pennsylvania. “But I don’t think they are undevelopable,” said Mr. Barrett, who is currently advising Tepco in relation to the decommissioning.



Nuclear Engineer: New
footage shows Reactor 1 has
“ruptured” containment
structure, most likely from
the explosion
Water to cool “what’s left of core” flowing into environment (VIDEO)


15 November, 2013


The Japan Times, Nov. 14, 2013: One leak came from a rupture in a sand-cushioned drain pipe installed at the bottom of the containment vessel.


Chris Harris, former licensed Senior Reactor Operator and engineer, Nutrimedical Report, Nov. 14, 2013 (at 29:00 in): They did indeed find water pouring out of several locations in Reactor 1′s containment structure and basically this shows that it was ruptured, most likely during the explosion that happened [...] As we discussed before, all the water that gets pumped in to cool what’s left of the core [...] it goes in and it’s falling back out again and goes right into the secondary side, which is basicallly the reactor building [...] Because the water level’s not going up into that part of the building, it’s flowing out into the environment. That’s not really good news.



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