<http://www.globalresearch.ca/why-tepco-is-risking-the-removal-of-fukushima-fuel-rods-the-dangers-of-uncontrolled-global-nuclear-radiation/5359188>
Why TEPCO is Risking the Removal of Fukushima Fuel Rods. The Dangers
of Uncontrolled Global Nuclear Radiation
By Yoichi Shimatsu
Global Research, November 24, 2013
After repeated delays since the summer of 2011, the Tokyo Electric
Power Company has launched a high-risk operation to empty the
spent-fuel pool atop Reactor 4 at the Dai-ichi (No.1) Fukushima
Nuclear Power Plant.
The urgency attached to this particular site, as compared with
reactors damaged in meltdowns, arises from several factors:
- over 400 tons of nuclear material in the pool could reignite
- the fire-damaged tank is tilting badly and may topple over sooner than later
- collapse of the structure could trigger a chain reaction and
nuclear blast, and
- consequent radioactive releases would heavily contaminate much of the world.
The potential for disaster at the Unit 4 SFP is probably of a higher
magnitude than suspected due to the presence of fresh fuel rods,
which were delivered during the technical upgrade of Reactor 4 under
completion at the time of the March 11, 2011 earthquake and tsunami.
The details of that reactor overhaul by GE and Hitachi have yet to be
disclosed by TEPCO and the Economy Ministry and continue to be
treated as a national-security matter. Here, the few clues from
whistleblowers will be pieced together to decipher the nature of the
clandestine activity at Fukushima No.1.
Accidents happen
The delicate rod-removal procedure requires the lowering of a steel
cylinder, called a transfer cask, into a corner of the pool and then
using the crane to lift the 300-kilogram fuel assemblies
(4.5-meter-tall bundle of fuel rods held inside a metal cage) one at
a time from the vertical array of rods up and then down into the
cask. The container can hold 22 assemblies for transfer to a
temporary cooling unit built next to Reactor 4 before these are moved
to a storage building.(1)
Lifting the 1,533 fuel bundles out of the pool is fraught with
danger. If an assembly breaks away and falls, the impact could
shatter other rods below, triggering an uncontrolled nuclear
reaction. Compounding the threat, many rods are not intact but were
fragmented into loose shards by a collapsing crane. In addition, many
of the rods likely lost their protective cladding during the two
fires that engulfed the spent-fuel pool on March 14 and 15, 2011.
The urgency of this transfer operation is prompted by the warping of
the supporting steel frame by the twin fires that followed the March
11 quake. The pool is also tilting. If the unbalanced structure
topples, the collapse would trigger nuclear reactions. A cascade of
neutrons could then ignite the nearby common fuel pool for Reactors 1
through 6. The common pool contains 6,735 used assemblies.(2)
The Reactor 4 spent fuel pool contains an estimated 400 tons of
uranium and plutonium oxide, compared with just 6.2 kilograms of
plutonium inside Fat Man, the hydrogen bomb that obliterated Nagasaki
in 1945. (While predictions are bandied about by experts and
bloggers, there exists no reliable method for calculating the
potential sum or flow rate of radiation releases, measured in
becquerel or sievert units, after an accident. The tonnage involved,
however, indicates only that a large-scale event is likely and a
cataclysm cannot be ruled out.)
More than 1,700 tons of nuclear materials are reported to be on site
inside Fukushima No.1 plant. (My investigative visits into the
exclusion zone indicate the existence of undocumented and illegal
large-scale storage sites in the Fukushima nuclear complex of
undetermined tonnage.) By comparison Chernobyl 's reactors contained
180 tons of fuel not all of which melted down.
Despite the looming threat to residents in Fukushima, surrounding
provinces and the capital Tokyo, the office of Prime Minister Shinzo
Abe along with TEPCO hews to the tradition of risk denial and
blackout of vital information. No contingency plan has been issued to
Fukushima residents or to the municipalities of the Tohoku and Kanto
region in event of a nuclear disaster during the SFP clearance
effort. A concurrent drive to impose a draconian law against
whistleblowers on grounds of national security is reinforcing the
cover-up of data and testimony related to nuclear power plants,
including the Fukushima complex.
Mystery of MOX super-fuel
A Mainichi Shimbun editorial mentions in passing that the Reactor 4
pool contains 202 fresh fuel assemblies.(3) The presence of new fuel
rods was confirmed in the TEPCO press release, which described the
first assembly lifted into the transfer cask as an "un-irradiated
fuel rod." Why were new rods being stored inside a spent-fuel pool,
which is designed to hold expended rods? What threat of criticality
do these fresh rods pose if the steel frame collapses or if crane
operators drop one by accident onto other assemblies, as opposed to a
spent rod?
Against the official silence and disinformation, a few whistleblowers
have come forward with clues to answer these questions. Former GE
nuclear worker Kei Sugaoka disclosed in a video interview that a
joint team from Hitachi and General Electric was inside Reactor 4 at
the time of the March 11, 2011 earthquake. By that fateful afternoon,
the GE contractors were finishing the job of installing a new shroud,
the heat-resistant metal shield lining the reactor interior.(4)
TEPCO inadvertently admitted to the presence of foreign contractors
at Fukushima No.1 up until March 12, 2012, when the management
ordered their evacuation in event of a massive explosion during the
rapid meltdown of Reactor 2. So far, leaks indicate the presence of
the GE team and of an Israeli nuclear security team with Magna BSP, a
company based in Dimona.(5)
Another break came in April 2012, when a Japanese humor magazine
published a brief interview of a Fukushima worker who disclosed that
radioactive pieces of a broken shroud were left inside a
device-storage pool at rooftop level behind the Reactor 4 spent-fuel
pool.(6) This undoubtedly is the used shroud removed by the GE-H
workers in February-March 2011.
A curious point here is that the previous shroud had been in use for
only 15 months. Why would TEPCO and the Japanese government expend an
enormous sum on a new lining when the existing one was still good for
many years of service?
Obviously, the installation of a new shroud was not a mere
replacement of a worn predecessor. It was an upgrade. The refit of
Reactor 4 was, therefore, similar to the 2010 conversion of Reactor 3
to pluthermal or MOX fuel. The same model of GE Mark 1 reactor was
being revamped to burn MOX fuel (mixed oxide of uranium and
plutonium).
The un-irradiated rods inside the Unit 4 spent-fuel pool are, in all
probability, made of a new type of MOX fuel containing highly
enriched plutonium. If the frame collapses, triggering fire or
explosion inside the spent-fuel pool, the plutonium would pulse
powerful neutron bursts that may well possibly ignite distant nuclear
power plants, starting with the Fukushima No.2 plant, 10 kilometers
to the south.
The scenario of a serial chain reaction blasting apart nuclear plants
along the Pacific Coast, is what compelled Naoto Kan, prime minister
at the time of the 3/11 disaster, to contemplate the mass evacuation
of 50 million residents (a third of the national population) from the
Tohoku region and the Greater Tokyo metropolitan region to distant
points southwest.(7) Evacuation would be impeded by the scale and
intensity of multiple reactor explosions, which would shut down all
transport systems, telecommunications and trap most residents. Tens
of millions would die horribly in numbers topping all disasters of
history combined.
Fires last time
The rod-transfer operation from Unit 4 is scheduled for completion by
the end of 2014. That estimate is optimistic since it does not take
into account the obstruction posed by fragments of shattered fuel
rods that were overheated in the two fires that swept through Unit 4
spent-fuel pool on March 13 and 15, 2011, according to NHK television
news.(8) Another factor for uncertainty is the impact of the
explosion that rocked the roofline of the reactor building.
Basing its analysis on corporate information releases thus far, the
Simply Info website states:
"TEPCO has changed their story on Unit 4 multiple times but
eventually admitted to a very obvious explosion occurring at Unit 4
(on March 15). No video of Unit 4 exploding exists to date and it is
assumed the explosion took place before dawn. One of TEPCO's later
admissions regarding unit 4 is that they think hydrogen leaked into
unit 4 from unit 3 via the venting pipes and a faulty valve. No
reason was given as to why unit 4 did not then ignite when Unit 3
exploded."(9)
Soon after the Reactor 3 blast, an explosion occurred on the roofline
of Reactor 4, blowing two 8-meter-wide holes through the outer wall.
Although tattered, the spent-fuel pool survived the nearby explosion
along with the device-storage pool containing the shroud. Photos of
the building show holes and damage to a large section of walls and
roof slabs on the northeast side of the upper structure (opposite the
spent-fuel pool). Hydrogen gas, despite its high combustive energy
per kilogram, lacks sufficient density to inflict such damage to
reinforced concrete, as would a carbon-bonded gas like acetylene. A
logical deduction then is that a cask of new fuel rods left on the
roof during the GE-H refit was ignited by neutrons emitted from the
SPF fire.
As for the spent-fuel pool, the first blaze broke out on March 14 and
died down after several hours. On the following day, the pool
reignited and had to be extinguished by firefighters. The nagging
question is why the raging fires burned so long, since much of the
hydrogen was dissolved in the remaining water at the bottom of the
pool or would have burned off within a few seconds. While TEPCO
conjectured that hydrogen gas pumped from Reactor 3 to 4, that
scenario is a long stretch since most of the volatile gas would have
dissipated before arrival or ignited along the way.
An alternative possibility is of a tritium-plutonium reaction
creating gas plasma inside the spent fuel pool. The condition of the
cladding on the rods, which would have been melted by plasma, can
indicate the heat source during those two fires. None dare mention a
tritium-plutonium inter-reaction because that is the formula for a
thermonuclear bomb, that is, the H-bomb. MOX fuel does have the
potential to generate sufficient tritium for a thermonuclear
reaction, and that is what so rattled Naoto Kan by March 12, 2011.
A Puzzled Civil Engineer
In July 2012, inside the exclusion zone about 14 kilometers south of
Fukushima No.1 plant, I had a discussion with a manager with a major
construction contractor, whose large team was working at the damaged
nuclear facilities. The civil engineer said that the Reactor 4
building was of serious concern because the structure was split, with
the halves leaning onto each other. He added that the tilt indicates
"structural damage" to the ferroconcrete foundation. Even a 9.0
earthquake could not cleave the strong footing, he stressed.
When asked about what then could crack the foundation, the manager
responded: "I am a civil engineer, not a nuclear expert." Nudged a
bit more, he implied that a meltdown of nuclear fuel may have seared
through the concrete. The intense heat can reconvert concrete into
loose hydrated lime powder and sand, while cutting through rebar
steel like a hot knife through butter.
The upgrade of the Reactor 4 shroud may well have involved the
test-fitting of some MOX rods, which were abandoned on the floor next
to the reactor when the tsunami reached shore. In other words, in
early March 2011 crane operators completely filled the space inside
the spent-fuel pool with new MOX rods and then simply left casks of
assemblies on the roof and lowered more into the basement. That is
the simplest explanation for the damage to the structural integrity
of the reactor building. GE is not about to disclose its role in this
disaster.
Yoichi Shimatsu, former editor of the Japan Times Weekly in Tokyo,
conducts independent radiation measurements and dispenses herbal
therapy to local residents on his 10 journeys since May 2011 into the
20-kilometer Fukushima exclusion zone.
Notes
1. Tokyo Electric Power Company, press release, 18 November 2013
2. Former Ambassador Mitsuhei Murata, quoted by the Asahi Shimbun,
"Doomsday scenarios spread about No.4 Reactor at Fukushima plant" 10
May 2012.
3. The Mainichi Shimbun, editorial "TEPCO must put safety above all
else in Fukushima atomic fuel removal project."
4. "GE Nuclear Plant Inspector/Whistleblower Kei Sugaoko Speaks"
youtube.com, 40 minutes
5. Israeli surveillance at Fukushima plant, Sarah Press, Israel21c,
March 20, 2011
http://israel21c.org/news/israeli-surveillance-at-fukushima-plant/
6. Datsutte-miru magazine, Interview of a Fukushima worker by
Oshidori Mako, April 15, 2012.
7. This writer attended the June 2013 seminar at the San Diego Board
of Supervisors and issuedthe most detailed news report on Naoto
Kan's remarks, "Japan's leader during Fukushima meltdown opposes
nuclear power", posted at http://rense.com/general96/jpleader.html
8. NHK World news broadcast, 15 March 2011, reported by Platts ( Sydney )
9. SimplyInfo, "Reactor 4", www.fukuleaks.org
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