(351.3489) WISE Amsterdam - Nuclear power plants can't operate without regular, deliberate releases of radio-active water and gases. The releases from the reactor building are needed to control the pressure, temperature, and humidity and to keep radioactivity from exceeding government limits for workers.
Think of water boiling in a kettle. The escape of steam relieves pressure inside. A nuclear power plant operates in much the same way: hot, radioactive gases inside the reactor building must be vented into the atmosphere. This is done through the vents that are built into the building. The vents have filters to stop some of the radio-active gases from being released. However, no filtering technology exists for some gases, like xenon-135, which decays into cesium-135, an isotope with a three-million-year half-life.
The kettle analogy also helps explain routine releases of radioactivity into the river, lake, or ocean that supplies a reactor's cooling water. As the water in the kettle boils, minerals build up on the interior. Likewise, radioactive corrosion products stick to the interior surfaces of the reactor vessel. Some of this radioactive "crud", as it is called, sloughs off into the reactor's cooling water. Fission products also enter the cooling water from leaks in the fuel rods, which contain the equivalent long-lived radioactivity of 1000 Hiroshima bombs.
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How does this contaminated water make its way into the environment? Given the maze of more than 50 miles of piping through which cooling water circulates, leaks are bound to occur. In fact, the US Nuclear Regulatory Commission allows leaks of up to 10 gallons a minute. And as a nuclear plant ages, the leaks generally increase.
Some contaminated water is intentionally removed from the reactor to reduce the level of radioactive and corrosive chemicals that damages valves and pipes. This radioactive water is "cleaned up" and either recycled back into the cooling system or released into the environment.
As with the plant's gases, not all radioactive isotopes can be filtered from the water. No economically feasible technology exists to do so. Tritium, or radioactive hydrogen, for example, cannot be filtered. Just as water containing ordinary hydrogen and oxygen is a component of all living cells, tritiated water, a major byproduct of nuclear power plant operation, can also be incorporated into all cells of the body. Many laboratory studies have shown that long-term chronic exposure to low concentrations of tritium is more damaging than previously believed. Some of the hazards resulting from tritium uptake include mutations, tumors, and cell death.
Other radioactive isotopes are also released without being filtered when they are at a concentration below the level the plant monitors are set to detect -- a level the government has decreed "acceptable". But "acceptable" doesn't mean safe; it means "as low as reasonably achievable". In other words, as low as the industry claims it can afford to achieve.
So, no one really knows how much radioactivity is released.
The nuclear industry and the NRC say we should not be concerned about these routine releases. But in a report published in December 1989, a National Research Council committee of radiation experts states that well demonstrated health effects from low-level radiation "include the induction of cancer, genetically determined ill-health, developmental abnormalities, and some degenerative diseases..."
In a June 1990 statement recom-mending more stringent radiation exposure limits for workers, the International Commission on Radiological Protection says: "New data and new interpretation of earlier information now indicate with reasonable certainty that the risks associated with ionizing radiation are about three times higher than they were estimated to be a decade ago." In addition, Dr. John Gofman, who co-discovered uranium-233 and founded the Biomedical Research Division of the Lawrence Livermore Laboratory, states in his most recent report on low-dose radiation that there is no such thing as a "safe dose" of radiation, and that a low dose received slowly causes as many cancers as the same dose delivered all at once.
The nuclear industry often justifies its routine releases of radioactivity by asserting that humans are constantly exposed to natural back-ground radiation that has nothing to do with nuclear weapons or power plants. However, while we cannot lower the level of natural radiation, no one has the right to add (hu)man-made radiation on top of it. Any exposure to radiation increases the risk of genetic mutations, cancer, and other life-shortening diseases. The short-term benefits of nuclear-generated electricity do not justify the possible long-term consequences of radiation exposure.
Nuclear power plants don't have to blow up or melt down to release radioactive poisons into our air and water. All it takes is their routine, everyday operation. Government and industry have known this for decades. It's time the public knew, too.
Source: The above is an article by Kay Drey published in "Viewpoint", a Forum on Energy and Environmental Issues and a service provided by the Washington-based Safe Energy Communication Council (US), Dec.1990.
Contact: Kay Drey, 515 West Point Avenue, University city, MO 63130, USA.
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