Given that the ICRP predicted excess cancers will probably appear in the next10 years, they will not be measurable above the normal rate unless they are rarecancers. Examples are leukaemia in children or thyroid cancer.The ECRR absolute risk method cannot be formally used unless we know theindividual radionuclide exposures. However it can be used if we approximate that 1/3of the dose is internal and that 1/3 of the internal dose carries a weighting of 300(which was the overall weighting factor obtained form the weapons test falloutspectrum of radionuclides epidemiology). Then the annual internal dose is 5.6mSvand 1/3 of this is 1.9mSv which we weight at 300. The total ECRR dose is thus575mSvECRR. The collective dose is then 3,338,900 x 575 x 10
-3
to give 1,919,867person Sieverts and a lifetime (50 year) cancer yield of 191,986 extra cancersassuming the ECRR risk factor of 0.1 per Sievert ECRR. Given the different timeframes, these numbers obtained from the Tondel et al 2004 regression and the ECRRabsolute model based on the atmospheric test cancer yields in Wales and England arein reasonable agreement.The three predictions are given in Table 5
Table 5
. The predicted cancer increases in the 100km zone near the Fukushima site
Sv/h for one yearECRR Tondel 103,329 In ten years following the catastrophe, based onsurface contamination onlyECRR absolute 191,986 In 50 years, based on collective doses atexposure of 2
µ
Sv/h for one year; probably halfof these expressed in the first ten years.
Cancer excess in 200km annulus population
The methods employed above may be extended to the 200km annulus if thecontamination levels are known. Presently no data is available of contamination inthese areas although dose rates are available. NOAAComputer modelling carried outby us and published on the internet (www.llrc.org) and elsewhere suggest that theplumes from the catastrophe have travelled south over the highly populated areasshown in Fig4. Dose rates have been published for these areas and from these doserates it can be assumed that significant exposures have occurred. From Table 4 andFig 3 we can assume that the exposures are of the order of 1
µ
Sv/h with associatedcontamination levels. Therefore the methods employed for the 100km area may beextended to the 200km area. The population is, however much greater at 7,874,600.The results
(HigginsBlog) – Despite countless reassurances that no harmful levels of radiation from the Japan nuclear fallout would hit the US from the EPA, the University of Berkley in California is now reporting that rainwater in San Francisco water has now been detected at levels 18,100% above federal drinking water standards.
Again, with just about all other news of the radiation hitting the US, the news is once again reported to the public over a week after it was first detected.
Plugging away: No highly radioactive water is seen leaking early Wednesday from the reactor 2 storage pit (top), where it was seen pouring from a crack Tuesday afternoon (bottom). KYODO PHOTO
Japanese workers have stopped the leak of radioactive water from the earthquake-damaged Fukushimanuclear power plant, but the situation is still far from under control, according to a confidential US Nuclear Regulatory report obtained by the New York Times. The report identifies a wide array of problems including build-ups of hydrogen gas that could cause explosions similar to those that crippled the plant soon after the earthquake. Workers have begun injecting nitrogen into a reactor to try to stabilize the hydrogen. Plant owners are also facing the problem of how to dispose of millions of gallons of radioactive wastewater – they’ve been dumping it into the ocean for several days now. Voice of America reports the dumping will continue until at least Friday.
(click link for audio/news.Also for Radio news USA)
Tokyo Electric Power Co. finally succeeded in stopping the main leak of highly radioactive water from the damaged Fukushima No. 1 nuclear plant into the ocean Wednesday morning and workers were preparing to inject nitrogen into at least one reactor in a bid to prevent another hydrogen explosion
Tepco said it confirmed at 5:38 a.m. that a crack in the No. 2 reactor storage pit had been plugged after workers injected 1,500 liters of sodium silicate and another agent to solidify a layer of small stones under a cable trench.
“I have been told that it is being thoroughly looked into whether the leak has completely stopped and whether there are other (cracks),” Chief Cabinet SecretaryYukio Edano said. “We have not stopped worrying just because the leak supposedly stopped.”
The highly radioactive water is believed to have come from the No. 2 reactor core, where fuel rods have partially melted, and ended up in the pit. The pit is connected to the No. 2 reactor turbine building and an underground trench connected to the building, both of which were found to be filled with high levels of contaminated water.
There have been many lab tests in the country where they contaminate the water 5 times higher than what EPA allows for consumption. Â They test this and distill water, retest and they find the residue that is left behind contains all the heavy metals, which are classed as radioactive.
Most of the heavy metals have a boiling point of 3092 degrees F, meaning the metals actually boil at that point. The boiling point of water is 212 F which is 2800 F below that. Heavy Metals are left behind as waste in the pot. Radiation is in the same family in the periodic chart as these heavy metals.
Does this mean you can take contaminated water and make it clean? Yes. The process is called thermo distillation which is heat. This can be very expensive to do for everyone’s supply but just for your own, this is very easy.
If you get an electric one, around $200, it distills a gallon of water overnight. There are distillers that can run on propane gas as well and wood fires for those who live OFF THE GRID.
Nor people are sure about dumping nuclear waste into the sea.
TOKYO – Workers discovered new pools of radioactive water leaking from Japan’s crippled nuclear complex, officials said Monday, as emergency crews struggled to pump out hundreds of tons of contaminated water and bring the plant back under control.
Officials believe the contaminated water has sent radioactivity levels soaring at the coastal complex, and caused more radiation to seep into soil and seawater.
The Fukushima Dai-ichi power plant, 140 miles (220 kilometers) northeast of Tokyo, was crippled March 11 when a tsunami spawned by a powerful earthquake slammed into Japan’s northeastern coast. The huge wave engulfed much of the complex, and destroyed the crucial power systems needed to cool the complex’s nuclear fuel rods.
Since then, three of the complex’s six units are believed to have partially melted down, and emergency crews have struggled with everything from malfunctioning pumps to dangerous spikes in radiation that have forced temporary evacuations.
Confusion at the plant has intensified fears that the nuclear crisis will last weeks, months or years amid alarms over radiation making its way into produce, raw milk and even tap water as far away as Tokyo.
The troubles at the Fukushima complex have eclipsed Pennsylvania‘s 1979 crisis at Three Mile Island, when a partial meltdown raised fears of widespread radiation release, but is still well short of the 1986 Chernobyl disaster, which killed at least 31 people with radiation sickness, raised long-term cancer rates, and spewed radiation for hundreds of miles (kilometers).
Photo Used With Permission of Joseph Gonyeau. Original Source: Virtual Nuclear Tourist
The spent fuel rods from a nuclear reactor are the most radioactive of all nuclear wastes. When all the radiation given off by nuclear waste is tallied, the fuel rods give off 99% of it, in spite of having relatively small volume. There is, as of now, no permanent storage site of spent fuel rods. Temporary storage is being used while a permanent site is searched for and prepared.
When the spent fuel rods are removed from the reactor core, they are extremely hot and must be cooled down. Most nuclear power plants have a temporary storage pool next to the reactor. The spent rods are placed in the pool, where they can cool down. The pool is not filled with ordinary water but with boric acid, which helps to absorb some of the radiation given off by the radioactive nuclei inside the spent rods. The spent fuel rods are supposed to stay in the pool for only about 6 months, but, because there is no permanent storage site, they often stay there for years. Many power plants have had to enlarge their pools to make room for more rods. As pools fill, there are major problems. If the rods are placed too close together, the remaining nuclear fuel could go critical, starting a nuclear chain reaction. Thus, the rods must be monitored and it is very important that the pools do not become too crowded. Also, as an additional safety measure, neutron-absorbing materials similar to those used in control rods are placed amongst the fuel rods. Permanent disposal of the spent fuel is becoming more important as the pools become more and more crowded.
Another method of temporary storage is now used because of the overcrowding of pools. This is called dry storage (as opposed to “wet” storage which we outlined above). Basically, this entails taking the waste and putting it in reinforced casks or entombing it in concrete bunkers. This is after the waste has already spent about 5 years cooling in a pool. The casks are also usually located close to the reactor site.
Permanent Fuel Storage/Disposal:
There are many ideas about what to do with nuclear waste. The low-level (not extremely radioactive) waste can often be buried near the surface of the earth. It is not very dangerous and usually will have lost most of its radioactivity in a couple hundred years. The high-level waste, comprised mostly of spent fuel rods, is harder to get rid of. There are still plans for its disposal, however. Some of these include burying the waste under the ocean floor, storing it underground, and shooting it into space. The most promising option so far is burying the waste in the ground. This is called “deep geological disposal”. Because a spent fuel rod contains material that takes thousands of years to become stable (and non-radioactive), it must be contained for a very long time. If it is not contained, it could come in contact with human population centers and wildlife, posing a great danger to them. Therefore, the waste must be sealed up tightly. Also, if the waste is being stored underground, it must be stored in an area where there is little groundwater flowing through. If ground water does flow through a waste storage site, it could erode the containment canisters and carry waste away into the environment. Additionally, a disposal site must be found with little geological activity. We don’t want to put a waste disposal site on top of a fault line, where 1000 years in the future an earthquake will occur, releasing the buried waste into the environment.
The waste will probably be encapsulated in large casks designed to withstand corrosion, impacts, radiation, and temperature extremes. Special casks will also have to be used to transfer fuel rods from their holding pools and dry storage areas next to the reactor to the permanent geological storage site.
Highly radioactive iodine seeping from Japan’s damaged nuclear complex may be making its way into seawater farther north of the plant than previously thought, officials say, adding to radiation concerns as the crisis stretches into a third week.
Mounting problems, including badly miscalculated radiation figures and no place to store dangerously contaminated water, have stymied emergency workers struggling to cool down the overheating plant and avert a disaster with global implications.
The coastal Fukushima Daiichi power plant, 220 kilometres northeast of Tokyo, has been leaking radiation since a magnitude-9.0 quake on March 11 triggered a tsunami that engulfed the complex. The wave knocked out power to the system that cools the dangerously hot nuclear fuel rods.
On Monday, workers resumed the laborious yet urgent task of pumping out the hundreds of tons of radioactive water inside several buildings at the six-unit plant. The water must be removed and safely stored before work can continue to power up the plant’s cooling system, nuclear safety officials said. That process alone could take weeks, experts say.
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