Tuesday, May 15, 2012

Fukushima Crisis is Over After One Year: NOT!

[Fukushima NukeBlog Index]

This piece from the World Nuclear Association, which is a platform for apologists of the Nuclear Power Industry is unbelievable in the extent they present the opposite of the MASS NUCLEAR DEATH scenario, which is EVERYTHING IS COMPLETELY UNDER CONTROL scenario which isn't exactly spot on either. i am reposting their piece with my comments.There is no mention of the massive damage to reactor buildings by explosions at units 1,3 and 4 which destroyed

Starting with the unbelievable conclusion: 


While by any measure the accident at Fukushima Daiichi has been severe and has negatively impacted the lives of a lot of people – particularly those who have had to evacuate {MORE LIKE RUINED THE LIVES OF 200,000 PEOPLE COMPLETELY AND LEFT A BIG HOLE IN THE GOVERNMENT WHICH IS PAYING FOR CLEANUP AND BAILOUT OF TEPCO}– the reactors are now properly under control (UNDER CONTROL? CRANES AND SYSTEMS TO REMOVE SPENT FUEL FROM POOLS WERE ALL DESTROYED AND NO KNOWN WAY TO REMOVE MELTED FUEL IN CONTAINMENT FLOOR??) and the situation at the site and in the surrounding areas is continuously improving due to the efforts of the site workers, decontamination experts and the Japanese people.


Fukushima Nuclear Accident: One Year On

 One year after an extreme natural disaster led to fuel melting at the Fukushima Daiichi nuclear power plant the situation is under control and the accident is officially over. {ARE YOU KIDDING?} Plant operator TEPCO is now focussed on decommissioning activities while the various levels of Japanese government are now concentrating on decontamination efforts, so that people evacuated in the early days of the accident can return home. {RETURN HOME TO AN ECONOMIC WASTELAND? YOU CAN'T SELL ANYTHING FROM 100 MILES FROM THE PLANT} This document summarises what has so far been accomplished in dealing with the accident, as well as listing the challenges that remain. {CHALLENGES? MORE LIKE IGNORING THE HUGE PROBLEMS THAT RE}

How the accident developed

On the 11 March 2011 a powerful earthquake brought down power lines in the northeast of Japan. About an hour later a devastating tsunami flooded the coast, inundating the Fukushima Daiichi nuclear power plant where it disabled backup generators at the site. {AND DESTROYED ALL OF THE CRITICAL COOLING SYSTEMS NEAR THE SHORE EVEN IF THE GENERATORS WERE NOT FLOODED} This started a chain of events that eventually caused fuel to melt at three of the six units (units 1-3) and caused serious structural damage to one more (unit 4). {PICTURE SHOWS THAT UNITS 5 AND 6 WHICH WERE HIEVEN HIGHER UP ON THE HILL WERE ALSO INUNDATED}This was the first time ever that a natural disaster has led to a serious nuclear accident {THAT WAS NEVER EVEN FORSEEN BY TEPCO OR INDUSTRY EXCEPT BY NUCLEAR ALARMISTS WHO HAPPENED TO BE RIGHT FOR ONCE}.  
Fukushima flooding
Fig 1: Satellite picture with estimation of tsunami inundation at the Fukushima site Source: TEPCO
The accident developed frenetically over the course of about a week and reached its worst point when several major {MAJOR???} airborne radioactive releases occurred beginning 15 March. A more thorough description of the early stages of the accident progression can be found in the Fukushima Accident Info Paper.

Core and fuel pool cooling

For months after the accident began, the primary challenge was that of trying to cool the cores of units 1-3. Even when no longer critical, the fuel in a nuclear reactor continues to produce a lot of heat after the reaction is shut down, and this must be removed to prevent it from heating up and melting. With the loss of normal systems, cooling was carried out by injecting water into the reactors using external pumps. Initially seawater was used – a step that effectively signified the writing-off of the reactors – but as a fresh water became available once more TEPCO switched to this. Later, all of the units recovered the use of their core-spray systems and used these along with the external pumps.
The emergency cooling effort could not prevent core melt from occurring in units 1-3. However it has prevented worse damage and no doubt prevented greater radioactive release. {THE GOOD NEWS IS THAT IT MIGHT HAVE BEEN WORSE?}  Most of the fuel, including all the uranium and plutonium, is thought to have slumped to the bottom of reactor pressure vessel in units 2 and 3, and to have fallen into the containment vessel of unit 1.  {BTW, THAT'S REALLY, REALLY BAD AND IMPOSSIBLE TO CLEAN UP WITH ANY KNOWN TECHNOLOGY} Only some of the volatile and water soluble elements have managed to escape containment.{JUST ENOUGH IN STEAM PLUME AND EXPLOSIONS 1 AND 3 TO CONTAMINATE SURROUNDING LAND TO CHERNOBYL LEVELS AND RUIN ALL AGRICULTURAL AND FOREST AND FISHING INDUSTRY AND MESS WITH TRASH AND SEWAGE AND CONTAMINATE RIVERS, ANIMALS AND FISH AND CONTAMINATE MILK AND RAINWATER ACROSS THE PLANET TO DETECTABLE LEVELS}
Another important objective was to make sure that the fuel in the spent fuel pools stayed covered and cool. In the early stages it was necessary to inject water into the fuel pool of units 3 and 4 but before long external cooling loops were set up making this unnecessary. Though at one time of great concern, subsequent monitoring confirmed that no radioactive material has escaped from this fuel. Unit 4 has now been reinforced {MORE LIKE PROPPED UP} against the possibility of another seismic event.
 Fukushima Reactor and Spent Fuel Pool
Fig 2: Schematic of reactor and spent fuel pool and the systems set up to prevent core melting and the spread of radioactive materials Source: TEPCO {YES THEY HAD TO USE FIRE ENGINES AS EMERGENCY PUMPS WHICH WERE DAMAGED BY EXPLOSIONS AT UNIT 1 AND 3}

Accident over

The aim of cooling was to get the reactors into ‘cold shutdown’; a state reached when temperatures in the core fall beneath 100C (the boiling point of water) and the pressure reaches equilibrium with the atmosphere. In the case of the accident affected Fukushima Daiichi units, this state represents a relative degree of stability. {WHICH MEANS YOU HAVE 3 REACTORS WHICH ARE A MELTED DOWN UNFIXABLE MESS LEAKING CESIUM CONTAMINATED WATER WHICH IS ACCUMULATING IN HUNDREDS OF HUGE TANKS ALL OVER THE SITE} The Japanese government officially declared this objective as being met on 16 December 2011, although temperature readings show that all three units had achieved this point by October.
RPV Temperatures
Fig 3: Temperatures declining over five months in the reactor pressure vessel (RPV) and the Primary Containment Vessel (PCV).The bottom axis states the date of measurement. Source: TEPCO

Water treatment

As water was being pumped in, it soon became clear that this was quickly leaking out of the pressure vessels and primary containment. Having been in contact with the damaged core this water was now highly radioactive and it was filling the reactor building basements, the turbine building basement and nearby tunnels (already partially filled by the tsunami). This water was preventing access to these areas and risked contaminating the wider environment. In April and June several major leaks occurred to sea.
Initially this water was pumped into storage tanks, but in June the first of three water purification facilities were set up to treat this water and to pump it back into the reactors. This ‘loop’ minimised the amount of fresh water required for cooling operations and has helped to capture a great deal of the total radioactive material released by the accident.{AND WHAT ARE THEY GOING TO DO WITH ACRES OF TANKS OF CONTAMINATED WATER?}
Water Treatment Programme at Fukushima
Fig 4: simplified picture of water treatment program. R/B = reactor building. T/B = turbine building. Source: TEPCO

Other accomplishments in stabilisation

Myths and misconceptions
While the path to reactor stabilisation has mostly been a linear one, with things consistently improving at the site day by day, there have been a few surprising occurrences which have in several cases been seized upon by some as proof of a sudden new deterioration. In truth they have been nothing of the sort.
Claims of re-criticality 
In September of last year TEPCO detected trace amounts of a short-lived radioactive isotope of xenon in unit 2 when they conducted measurements of gas in the reactor. This sparked fears of a recriticality. However, after performing various checks this xenon was confirmed as being due to very low level of spontaneous fission – a process that takes place naturally in certain heavy elements and is one of the pathways by which they decay.
Claims of a sudden temperature rise in February 
At the beginning of February 2012 TEPCO reported that following a change in water injection rates, a sudden temperature increase was being measured by one of the thermometers at the bottom of the unit 2 RPV. However the other two thermometers were not backing this up, and as TEPCO responded by altering flow rates these indicated falling temperatures. Further testing revealed no evidence of re-criticality but did show an increased electrical resistance in the thermometers circuit, leading TEPCO to conclude it was malfunctioning.
Cooling and water treatment activities at the Fukushima Daiichi site remain ongoing. Other work has focussed on keeping radiation levels down or reinforcing damaged structures, including:
  • Radioactive rubble has been mapped and a substantial amount has been cleared to improve site access. A special inhibitor has been sprayed on soil at the site to prevent further emissions to the atmosphere{THEY HAVEN'T MADE A DENT ON CLEANING UP THE MESS OF RADIOACTIVE RUBBLE?}
  • A cover has been built over the unit 1 reactor building to prevent emissions. Covers are due to be installed over units 3 and 4 in 2012.
  • An additional  support structure has been put in place under the unit 4 fuel pool
  • Barriers have been erected in the sea next to the units to prevent contaminated water from escaping
In addition to the above, temporary living facilities have been constructed to house the many workers present on site and substantial efforts have been made to improve radiation monitoring and reduce worker doses. While six workers ended up exceeding the government set emergency worker dose limit during the emergency, none received doses that would threaten their health and controls are now much tighter.{A HANDFUL OF HEALTHY WORKERS DIED SUDDENLY WITH ACUTE LUKEMIA SYMPTOMS WITH NO EXPLANATION}
The unique challenges surrounding the Fukushima Daiichi nuclear accident have given rise to many innovative solutions such as:
  • The use of concrete pump trucks to direct water into the fuel pools in the early days of the accident
  • Employing a floating platform as a water storage tank
  • Sending prototype robots into the reactor buildings and PCVs to determine radiation levels and the location of nuclear fuel
  • The setting up of first-of-a-kind filtration systems capable of separating large amounts of radioactive material
There have also been many setbacks also on the path to stabilisation, but with persistence each one has been overcome.

Today – at the site

For the 3000 workers currently employed at the site there is a lot of work left to do. With steps 1 and 2 of their accident recovery roadmap now officially finished, TEPCO has moved onto phase 1 of its long term strategy for decommissioning. This may take up to 40 years, {WILL PROBABLY TAKE MORE LIKE FOREVER, NOT 40 YEARS}but this long timescale is not in itself unusual for the decommissioning of a nuclear power plant. {WHICH IS WHY IT IS UNREALISTIC AS A MELTED DOWN REACTOR WILL TAKE MUCH, MUCH LONGER THAN AN UNDAMAGED PLANT ASSUMING IT CAN BE DISMANTLED AT ALL SAFELY} The greatest challenge lies in researching the techniques {RESEARCHING = THEY HAVE NO IDEA OF HOW SAFELY FIX OR DISMANTLE IT}required to safely remove and dispose of the fuel debris and other radioactive waste created by the accident.
 Tepco Fukushima Roadmap
Fig 5: TEPCO’s mid to long term roadmap strategy summary

Radioactive releases

The accident caused a large amount of radioactive material, mainly radioactive caesium and iodine, to be released which contaminated the local region. {MASSIVE UNDERSTATEMENT} Contamination of the sea also occurred and though this has now greatly diluted, some radioactive material has accumulated on the seafloor. The highest contamination occurred close to the plant though high radiation levels were also detected about 50 kilometres out to the northwest and in some small self-contained spots dotted throughout the countryside.
The threat of radioactive release caused the government to order a 20 kilometre evacuation zone to be set up around the stricken plant on Saturday 12 March. A further zone extending from 20-30 kilometres was declared an emergency preparedness evacuation zone in which people were instructed to stay indoors, or to leave and head for the nearest evacuation centres. This restriction was lifted on 30 September 2011. In April a deliberate evacuation zone was set up in the area stretching to the northwest were dose rates to the local population might conceivably exceed 20 milliSieverts per year.
About 100,000 people have been evacuated in total. It is worth noting that so far nobody has died or received a life-threatening dose as a result of radiation from the Fukushima Daiichi nuclear accident and no one is expected to.{HUNDREDS OF DIED AS A RESULT OF EVACUATION, AND SUICIDE CAUSED BY DESTRUCTION OF JOBS AND LIVELIHOODS, MORE THAN CHERNOBYL. TEPCO AND GOVERNMENT HAVE NOT INVESTIGATED "MYSTERIOUS" SUDDEN DEATHS THAT MAY WELL HAVE BEEN DUE TO RADIATION EXPOSURE POORLY DOCUMENTED}
Fukushima Evacuation Zones
 Fig 7: A map of the evacuated areas. The red area was originally evacuated as a precaution against radiation doses which might cause immediate health effects, however it remains evacuated to this day. The orange band to the northwest contains areas where doses to individuals may possibly exceed the government-set restriction of 20 milliSieverts in one year. The yellow zone, now no longer in effect, was set for residents to evacuate if conditions at the Fukushima plant deteriorated further.  Source: IAEA.
It should be noted that the radiation levels have greatly decreased since the early days of the accident due to several reasons. Firstly the radioactive element iodine 131, which was the single largest contributor to radiation levels for some weeks after the accident has completely decayed leaving mostly caesium 137 – a longer-lived but less harmful radioisotope. {HOT SPOTS CAUSED BY CESIUM CONCENTRATION IS MUCH MORE DANGEROUS THAN IODINE - IT CAN KILL ABOVE 1000 MSV} Secondly, weather effects such as rainfall and snow have also acted to reduce levels.{BUT CONTAMINATE RIVERS AND GROUND WATER}
Almost all the airborne emissions from the plant took place within the first couple of weeks. Within a month the rate of emission had fallen by a factor of 10,000. By August the amount of radioactive material being emitted to the atmosphere was within the levels acceptable for an operating nuclear power plant. {WHICH IS PRETTY GOOD CONSIDERING THAT ALL LEVELS OF SAFETY CONTAINMENT HAVE BEEN BREACHED AND ROOFS AND WALLS HAVE BEEN BLOWN OUT AND BASEMENTS ARE STILL FULL OF RADIOACTIVE WATER}
Fukushima emissions rate
Fig 8: A graph showing the estimate rate of emission (Becquerels per hour) over nine months from the accident stricken plant. Each step down on the vertical scale represents a 10-fold reduction. Source: TEPCO
The government set evacuation criteria of 20 milliSieverts per annum is widely acknowledged as being very conservative. There are several places on where the background radiation levels due to natural sources result in a much higher dose to local populations without any negative health effects. In areas in India, Brazil and Iran this background radiation can and does result in doses to people which exceed 100 milliSieverts per year.

Decontamination effort

The central government has set demanding targets for decontamination of the environment before residents can be allowed to return. They aim to initially reduce the level of extra exposure to less than 20 milliSieverts per year in all areas; and in areas frequented by children, such as schools and kindergartens, to less than 1 milliSieverts per year. The long term target is for all areas to be reduced to less than 1 milliSievert per year.  To achieve this, local and regional authorities have begun organising clean-up tasks such as removing five centimetres of top soil from park areas, pressure-washing buildings and roadways, and clearing drains gutters and ditches.
Fig 9: Decontamination efforts in the local area. Source: Ministry of Economy Trade and Industry
This decontamination effort (particularly removing so much soil) could well cause greater environmental damage than the radiation. An IAEA mission to the region in October urged a pragmatic clean-up, noting that the current strategy would succeed in creating a very large amount of low-level radioactive waste with very little meaningful gain in terms of reducing dose. The government has itself acknowledged that a 40% reduction of radiation levels is expected to take place naturally over two years as a result of weathering effects and natural decay. Nevertheless, they remain committed to their targets.
Many ordinary civilians are participating in this work, hoping to rebuild the communities that have been disturbed as a result of the evacuation.

Other Japanese nuclear plants

In deference to the understandably heightened public anxiety about the safety of nuclear power, from March through to June last year plant operators all over Japan decided not to restart reactors shut down for maintenance and periodic inspection. To address concerns, the central government announced in June that each idled plant would have to pass the first stage of a two-stage ‘stress test’ process before being allowed to restart. This means that as of the time of writing only two of the country's 50 operable reactors are generating electricity as more plants have shut for maintenance. Many operators have now submitted ther first stage stress test results to the regulator, but no authorisation has yet been given to restart.
This situation has in fact brought parts of the country perilously close to blackouts at times of peak demand and resulted in approximate $50 billion of increased fossil fuel imports to the nation for the year. It has also completely destroyed any hope Japan had of meeting its greenhouse gas reduction targets, and somewhat ironically as a result of increased levels of volatile organic compounds and particulate matter from burning fossil may result in an increased incidence of cancer and other health complaints. A World Health Organisation report release in September estimated that globally about 1 million preventable premature deaths took place in 2008 as a result of excessive air pollution – much of which was due to the burning of fossil fuels for transport and energy.


While by any measure the accident at Fukushima Daiichi has been severe and has negatively impacted the lives of a lot of people – particularly those who have had to evacuate – the reactors are now properly under control and the situation at the site and in the surrounding areas is continuously improving due to the efforts of the site workers, decontamination experts and the Japanese people.

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