October 25, 2013
Early in 2014, Tokyo Electric Company intends to begin the full-scale operation of their Advanced Liquid Processing System (ALPS) at Fukushima Daiichi. It will remove 60+ radioactive isotopes remaining in the currently-stored wastewater that has been run through the Cesium absorber system. It seems ALPS will use high-efficiency resin beds to strip the materials from the liquids flowing through them. http://www.tepco.co.jp/en/nu/fukushima-np/handouts/2013/images/handouts_130329_01-e.pdf
The resulting water will be so pure that it will not conduct electricity very well, if at all. Only one radioactive isotope will remain – Tritium. The ultimate question will be whether or not Tepco’s allowed to release the ultra-clean Tritiated water into the sea, mitigating their wastewater buildup problem. Any detectible radioactivity makes millions of Japanese fear for their lives, and the mere thought of eating seafood that might contain something radioactive makes many consumers shun fish caught off the Fukushima coast. The Fisheries of Fukushima have already declared that they will never agree to allow Tritiated water releases to the sea, no matter what.
Tritium is the radioactive isotope of Hydrogen and one of the numerous radioactive isotopes produced by Mother Nature, in this case caused by upper-atmospheric collisions between energetic molecules and cosmic rays. Tritium has one proton in its nucleus, which makes it Hydrogen. But, it also has two neutrons attached to the proton, which is why it is symbolized as H-3. The two neutrons cause the nucleus to be a bit unstable. The resulting radioactive process goes like this – one of the neutrons spits out an electron, turns into a proton, and the Tritium instantly becomes non-radioactive Helium (He-3). The freed electron is called a Beta particle, incorrectly dubbed a “beta ray” by the Press. Gamma and X-ray radiations are “rays” because they are a continual flow of energy. Betas are negatively-charged sub-atomic particles…not rays.
Betas are about the weakest of the various forms of ionizing radiation. The most energetic Beta’s known to man (~7 Mev and up) cannot penetrate heavy-duty aluminum foil. Tritium’s Betas are among the weakest of the lot (~6 KeV) – a thousand times weaker than the just-mentioned high-power Betas. As a result, Tritium’s Betas can be stopped by cheap, thin cellophane, and are completely attenuated by our skin.
Because it is hydrogen, Tritium is part of the water molecule. This is why it cannot be removed by Fukushima’s Cesium absorption units, reverse osmosis system (to reduce salt concentration), or ALPS resin beds. Water cannot be removed from water, if you will. Separating Tritium from non-radioactive water is possible, but a slow and expensive process. There are international markets for Tritium including biomedical research and some glow-in-the-dark technologies such as emergency exit signs and remote-location airport runway lights. In all cases, the technologies produce less radiation exposure than household smoke detectors. The advantage is that the Tritium-based equipment needs no power to operate and never stops working.
While building a Tritium removal facility at F. Daiichi for international marketing might seem a reasonable solution, the financial investment would be massive and the demand is limited. Tepco doesn’t have the money for it. Further, all Tritium removal technologies only reduce concentrations, but cannot get all of it out. To Japan’s radiophobic demographic, this will not be good enough. To them, the only acceptable release will be no release.
Tepco cannot build more and more wastewater tanks ad infinitum. At some point, the stored-water buildup must stop. Inevitably, the Tritiated waters will have to be released into the ocean. There is no other option, as recently stated by expert consultants Lake Barrett, Dale Klein, and Lady Barbara Judge. When the inevitable happens, it will surely become a major issue producing a huge amount of negative Press around the world, along with apocalyptic what-if scenarios from the prophets of nuclear energy doom.
And, for what?
Tritium has never been found to actually cause death to any human being…ever…anywhere in the world. There is one case of a woman accidently ingesting 37 billion Becquerels of Tritium, resulting in detectible chromosomal aberrations for 11 years – all were repaired by her body’s natural mechanisms. (NCRP, 1979) Other than this, no negative health effects to humans due to Tritium have ever actually happened. Because of this, both the US EPA and NRC assume that because Tritium is radioactive at very low every levels, and all radiation causes damage to living cells, exposure via ingestion necessarily places people at an extremely low level of risk.
In 2006, the state of California ran an intensive study on the Tritium issue and found that the EPA and NRC-imposed limits on Tritium in water are based on carcinogenic assumptions. http://oehha.ca.gov/water/phg/pdf/phgtritium030306.pdf In addition, they found that the only evidence for any negative health effects comes from exposing lab mice to enormous levels of Tritium, in excess of 37,000,000 Bq/liter! While some of the specimens grew excess tumors, none of them were fatal. The report says, “Apparently, animals were not dying from tumors associated with tritium exposure.” In the very next paragraph, the report states, “We have found no human data that specifically addresses the carcinogenic effects of tritium.” Why? Because there is none! Regardless, the California state limit on Tritium in water was adopted directly from the US national standard of 20,000 Bq/liter. Drinking two liters per day at this level would result in an assumed annual internal exposure of 0.3 millisieverts per year. No fatal cancers have ever been documented below 1500 millisieverts per year in humans due to any form of ionizing radiation. It should be noted that Japan’s limit for release is 60,000 Bq/liter. Unquestionably, the US and California limits on Tritium are ultra-ultra-conservative. We might even judge them to be absurd…but that’s another issue for another time.
Using the above facts as background, we can look at the Tritium levels in the wastewaters at F. Daiichi and reasonably evaluate whether or not it will be worth getting upset about after ALPS does its job. The highest Tritium activity level at F. Daiichi is 630,000 Bq/liter in samples taken from the untreated turbine building basements. There’s no reason to think the waters inside any of the storage tanks at F. Daiichi have higher concentrations. Thus, after ALPS does its job, around 630,000 Bq/liter of Tritium will remain. Although it is a little more than 30 times higher than America’s standard for release, dumping it directly into the sea wouldn’t harm a mouse, let alone a fish or anyone eating the fish. But, Tepco and the government will probably not do that. Instead, it seems they will dilute the ALPS-cleansed waters with non-tritiated freshwater, well-below whatever limit they will ultimately set, before releasing it to the sea.
Along the way, the Press will make a mountain out of this virtual mole-hill, Japan’s antinuclear demographic will scream bloody-murder, and the international prophets of nuclear energy doom will guarantee widespread cancer epidemics along the Pacific Rim. All because of a low energy form of radiation that couldn’t hurt a mouse!