Reactor #4 Spent Fuel Pool

SUBHEAD: This damaged pool high in an unstable structure contains enough fiery poison to damage the northern hemisphere.

By Juan Wilson on 16 September 2013 for Island Breath -
(http://islandbreath.blogspot.com/2013/09/fukushima-reactor-4-fuel-pond.html)


Image above: Top of one of 1,533 fuel rods in Spent Fuel Pool in Reactor Building #4 at Fukushima Daiichi Nucleat Power Plant on 25 march 2012. Loop on top is for hook to pull fuel rod from cooling pool assembly. Still image from video below.

The talk show pundidiots focus on who got the best of who in Syria. Was it Putin or Obama? The squabble about getting control of and dispensing with some containers of sarin gas takes center stage in a world where the largest living environment on the planet - namely the Pacific Ocean - is threatened by increasing withering radiation poisoning that may already be out of human capacity to control.

Getting the Priorities Straight
It's time to recognize that this disaster in Japan as the great immediate threat to the United States, China and Russia. The Security Council of the United Nations needs to identify this. It should become the highest security priority in the world. All resources available need to be provided to handle what is the possibly the worst single man made event in human history.

In the meantime typhoon Man-Yi is throttling Japan. Fukushima Daiichi workers are using large weights to try and prevent large work cranes from toppling over in high winds. They also attached guy ropes to stabilize external piping and pumps, which are used to circulate cooling water to and from the reactors.

Ongoing Concerns
There are three main areas of threat to the world at the Fukushima site.  These threats will increase and as the site is further contaminated, will be harder and harder to deal with. The threats are:
  1. COOLING WATER: Massive radioactive contamination of cooling and ground water. This water has not successfully been contained onsite. Countless tons of radioactive water are entering the Pacific Ocean everyday with no end in sight.

  2. MELTED CORES: Reactor buildings 1, 2 and 3 had meltdowns of their cores that consisted of several hundred tons each. Each core has burned through its reactor vessel. It is not known if any or all have burned through the foundation of their containment building.  Any interruption in the flow of cooling water threatens to drive the melted nuclear cores into an uncontrolled nuclear chain reaction with unpredictable devastating results.

  3. COOLING POOLS: Each of the six site reactor buildings have elevated spent fuel cooling pools to store spent and replacement fuel rods. Reactor #4 was offline at the time of the 3/11/11 earthquake and tsunami. All its fuel rods and used rods were in its elevated cooling pool. The earthquake and subsequent catastrophe structurally damaged the building and left the precarious cooling pools subject to collapse. If the pool structure fails the fuel rod cladding will melt off and the fuel will ignite. A resulting nuclear explosion is possible that would dwarf the Hiroshima atomic bomb.Many tons of highly radioactive heavy particles would be lofted into the jet-stream and heading our way.
These three threats are real and present dangers to all life in the Pacific region (half the planet). The most immediate and possibly most widely dispersed may well be #3. Widespread fallout from a nuclear explosion resulting in the world-wide distribution of long-lived cancer producing radioactive uranium/plutonium particles pose a lethal danger to anyone in their path.

 I hope this convinces Stewart Brand, James Lovelock, James Hansen and Bill Gates that its not worth keeping the grid up for our civilization if it means depending on nuclear power.

Fuel Rod Removal Woes
Adding to the structural damage to reactor #4 is the likelihood that cooling water used to keep fuel rods from igniting has saturated the ground and liquified the soil. Parts of the Reactor 4 complex has sunk unevenly as much as 30 inches. 

The fuel rods must be removed from unit #4 before it collapses. The plan is to begin removing fuel rods in November. That task is planned to take four years. It is apparent from inspections that the reactor #4 spent fuel pool had its water boil after the plant power system failed following the tsunami. Fuel rod cladding was probably compromised weakening the rod integrity.

More over, the building went through a structurally damaging earthquake. The concrete roof of the containment building collapsed onto the pool structure. The frame was distorted by the earthquake and uneven settling is adding to problems of the integrity and alignment of the fuel rod rack structure.

Normally the structure that makes up the fuel rod cooling pool is plumb and true. The rack system supporting the fuel is intact. The fuel rods sealed are undamaged. Even in this normal situation the fuel rods are removed or added to the pools with computer assisted crane movements. In the task at hand there will be no computer assist. Even the cranes themselves may be compromised by the spraying of cooling salt water onto the top of the building.

Each of the 1,533 fuel rods, weighing 660 pounds and 15 feet long, will have to be extracted straight out with manual control by a person on the crane. Each without error, without disintegration, and without getting caught up in the fuel rod assembly rack. A daunting task.

Consequences are real
This is a commentary by Micael Cllins on 19 June 2012 for Enviironmental Reporter:
"Japan courts a potential country‑killing catastrophe as it literally puts the lid on any chance of saving a nuclear reactor's spent fuel pool before further disaster strikes.

In the process, the situation has gravely worsened and is far more likely to precipitate the very calamity the Japanese government and Fukushima‑Daiichi owners purport to be trying to stop ‑ an uncontrollable and never‑ending nuclear fire which could take over a hundred years to burn through over 3 million pounds of hot goo.

But not just any nuclear fire, an unquenchable fission‑fed fire water can't cure. It would release so much gamma radiation that Fukushima would have to be abandoned ‑ those flimsy white suits seen in photos of Fukushima workers provide minimal protection only against alpha and beta radiation.

Abandoned, the entire site's spent fuel pools would eventually dry up and ignite with an uncontrollable nuclear conflagration that would burn for hundreds of years. Just Unit 4's spent fuel pool alone would release more than 85 times the amount of cesium‑1 37 let loose by the 1986 Chernobyl meltdown."


The Real Fukushima Dangers

By Stall of 14 September 2013 for the Washington Blog - 
(http://www.washingtonsblog.com/2013/09/the-real-fukushima-danger.html)


Video above: One minute from underwater survey of Fukushima #4Spent Fuel Rod Pool on 8 May 2011. From (http://youtu.be/QVqfPCsl2AA).

[IB Publisher's note: Below are portions from an overview of the Reactor #4 spent fuel cooling pool dangers.]

If one of the pools collapsed or caught fire, it could have severe adverse impacts not only on Japan … but the rest of the world, including the United States.   Indeed, a Senator called it a national security concern for the U.S.:
The radiation caused by the failure of the spent fuel pools in the event of another earthquake could reach the West Coast within days. That absolutely makes the safe containment and protection of this spent fuel a security issue for the United States.
Nuclear expert Arnie Gundersen and physician Helen Caldicott have both said that people should evacuate the Northern Hemisphere if one of the Fukushima fuel pools collapses. Gundersen said:
Move south of the equator if that ever happened, I think that’s probably the lesson there.
Former U.N. adviser Akio Matsumura calls removing the radioactive materials from the Fukushima fuel pools “an issue of human survival”.

So the stakes in decommissioning the fuel pools are high, indeed.

But in 2 months, Tepco – the knuckleheads who caused the accident – are going to start doing this very difficult operation on their own.

The New York Times reports:
Thousands of workers and a small fleet of cranes are preparing for one of the latest efforts to avoid a deepening environmental disaster that has China and other neighbors increasingly worried: removing spent fuel rods from the damaged No. 4 reactor building and storing them in a safer place.
The Telegraph notes:
Tom Snitch, a senior professor at the University of Maryland and with more than 30 years’ experience in nuclear issues, said  “[Japan officials] need to address the real problems, the spent fuel rods in Unit 4 and the leaking pressure vessels,” he said. “There has been too much work done wiping down walls and duct work in the reactors for any other reason then to do something….  This is a critical global issue and Japan must step up.”
The Japan Times writes:
In November, Tepco plans to begin the delicate operation of removing spent fuel from Reactor No. 4 [with] radiation equivalent to 14,000 times the amount released by the Hiroshima atomic bomb. …. It remains vulnerable to any further shocks, and is also at risk from ground liquefaction. Removing its spent fuel, which contains deadly plutonium, is an urgent task…. The consequences could be far more severe than any nuclear accident the world has ever seen. If a fuel rod is dropped, breaks or becomes entangled while being removed, possible worst case scenarios include a big explosion, a meltdown in the pool, or a large fire. Any of these situations could lead to massive releases of deadly radionuclides into the atmosphere, putting much of Japan — including Tokyo and Yokohama — and even neighboring countries at serious risk.
CNBC points out:
The radioactive leak at Japan’s Fukushima nuclear plant is far from under control and could get a lot worse, a nuclear energy expert, who compiles the annual “World Nuclear Industry Status Report” warned.

The big danger – and it was identified by Japan’s atomic energy commission – is if you lose water in one of the spent fuel pools and you get a spent fuel fire.
CNN reports:
[Mycle Schneider, nuclear consultant:]  The situation could still get a lot worse. A massive spent fuel fire would likely dwarf the current dimensions of the catastrophe and could exceed the radioactivity releases of Chernobyl dozens of times. First, the pool walls could leak beyond the capacity to deliver cooling water or a reactor building could collapse following one of the hundred  of aftershocks. Then, the fuel cladding could ignite spontaneously releasing its entire radioactive inventory.
Reuters notes:
The operator of Japan’s crippled Fukushima nuclear plant is preparing to remove 400 tons of highly irradiated spent fuel from a damaged reactor building, a dangerous operation that has never been attempted before on this scale.

Containing radiation equivalent to 14,000 times the amount released in the atomic bomb attack on Hiroshima 68 years ago, more than 1,300 used fuel rod assemblies packed tightly together need to be removed from a building that is vulnerable to collapse, should another large earthquake hit the area.

Tokyo Electric Power Co (Tepco) is already in a losing battle to stop radioactive water overflowing from another part of the facility, and experts question whether it will be able to pull off the removal of all the assemblies successfully.

“They are going to have difficulty in removing a significant number of the rods,” said Arnie Gundersen, a veteran U.S. nuclear engineer and director of Fairewinds Energy Education, who used to build fuel assemblies.

The operation, beginning this November at the plant’s Reactor No. 4, is fraught with danger, including the possibility of a large release of radiation if a fuel assembly breaks, gets stuck or gets too close to an adjacent bundle, said Gundersen and other nuclear experts.

That could lead to a worse disaster than the March 2011 nuclear crisis at the Fukushima plant, the world’s most serious since Chernobyl in 1986.

No one knows how bad it can get, but independent consultants Mycle Schneider and Antony Froggatt said recently in their World Nuclear Industry Status Report 2013: “Full release from the Unit-4 spent fuel pool, without any containment or control, could cause by far the most serious radiological disaster to date.”The utility says it recognizes the operation will be difficult but believes it can carry it out safely.
Nonetheless, Tepco inspires little confidence. Sharply criticized for failing to protect the Fukushima plant against natural disasters, its handling of the crisis since then has also been lambasted...

The process will begin in November and Tepco expects to take about a year removing the assemblies, spokesman Yoshikazu Nagai told Reuters by e-mail. It’s just one installment in the decommissioning process for the plant forecast to take about 40 years and cost $11 billion.
Each fuel rod assembly weighs about 300 kilograms (660 pounds) and is 4.5 meters (15 feet) long. There are 1,331 of the spent fuel assemblies and a further 202 unused assemblies are also stored in the pool, Nagai said...
Spent fuel rods also contain plutonium, one of the most toxic substances in the universe, that gets formed during the later stages of a reactor core’s operation...
“There is a risk of an inadvertent criticality if the bundles are distorted and get too close to each other,” Gundersen said.
He was referring to an atomic chain reaction that left unchecked could result in a large release of radiation and heat that the fuel pool cooling system isn’t designed to absorb.
“The problem with a fuel pool criticality is that you can’t stop it. There are no control rods to control it,” Gundersen said. “The spent fuel pool cooling system is designed only to remove decay heat, not heat from an ongoing nuclear reaction.”
The rods are also vulnerable to fire should they be exposed to air, Gundersen said. [The pools have already boiled due to exposure to air.]


Video above: More debris in Spent Fuel Pool #4. A 7:45 minute from underwater survey of Fukushima #4 Fuel Rod Cooling Pool in 25 March 2012. From (http://youtu.be/5Pk_K8lJ55c).

See also:
Ea O Ka Aina: Fukushima Not Going Away 9/9/13
Ea O Ka Aina: Fukushima Out of Control 9/1/13
Ea O Ka Aina: Fukushima House of Horrors 8/21/13
Ea O Ka Aina: Fukushima Radioactive Dust 8/19/13
Ea O KA Aina: Fukushima Apocalypse 8/17/13
Ea O Ka Aina: Cocooning Fukushima 8/15/13
Ea O Ka Aina: Fukushima Radiation Coverup 8/12/13
Ea O Ka Aina: G20 Agenda Item #1 - Fix Fukushima 8/7/13
Ea O Ka Aina: Fukushima & Hyperthyroid in Hawaii 4/1/13
.

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