George Glasier, a local rancher in Montrose County with experience in previous uranium businesses, announced that he was planning to open a new uranium mill near Naturita to supply the rapidly expanding overseas nuclear reactor markets. The new mill would be the basis for a major restart of uranium mining in Western Colorado. As expected, the local residents have expressed mixed reactions about a possible uranium business startup.
The Durango Herald published a series of four articles about the controversies surrounding the plan, providing much useful information (Aug. 9 to Aug. 12). But if the major concern is the possibility that the detrimental health effects from radiation exposure found in the previous uranium mining efforts will be repeated in any new startup, then the coverage was incomplete and, in certain cases, misleading.
Left out of the discussion was any reference to the extreme urgency that motivated both the development of a nuclear bomb, and the subsequent weapons race with the Soviet Union, that the early uranium mining was required to support. Historians have identified urgency as the cause of many of the previous health problems because it demanded action rather than caution when faced with radiation levels of undetermined lethality.
The urgency was driven by those scientists who had recently escaped from Germany and were intimately aware that those who remained behind knew as much about how to build a nuclear weapon as they did. They also understood, more than most, that the destructiveness of the weapon they were racing to develop would allow the first country that was successful to win the war. The fact that the Germans never fully implemented their knowledge was not discovered until after the war was over.
The urgency continued into the arms race because of the need to match Soviet production levels in order to maintain a deterrent against a surprise attack. It is important to acknowledge the role urgency played in causing radiation illnesses because that type of pressure will not be involved in mining and milling uranium to support generating electricity.
The most important omission from the Herald coverage, however, was the evidence about radiation health effects obtained by the National Academy of Sciences' Radiation Effects Research Foundation. The foundation studied 50 years of Hiroshima and Nagasaki survivors, and its final report was published in 1999.
The findings allowed the government, for the first time, to set specific and reliable safe levels for radiation exposure. By emphasizing past mistakes and oversights, and not how those mistakes could be prevented given new information about radiation risks, the Herald articles exaggerated the possibility that health problems of the past could happen again in any startup of uranium mining.
The foundation results showed indications of cancer are clear-cut only above 200,000 millirems lifetime exposure, although there is weaker evidence down to about 100,000 millirems. The Nuclear Regulatory Commission has set a safe level, over and above background levels, of 500 millirems per year. The background radiation in Colorado can reach 600 millirems per year in some locations. So, the safe level in the state would be 1,100 millirems per year. Dividing 1,100 millirems into 100,000 millirems lifetime limit (the lower boundary before any observed health damage from cancer would occur) shows it would take 91 years of continuous exposure in a mine or a mill for a worker to reach that unsafe level. These days, uranium workers are required to be equipped with radiation exposure meters to insure that safe levels are not exceeded.
One other finding about radiation protection, not well described in the articles, concerns the progress that has been made to reduce the incidences of lung cancer. When it was determined the major cause was breathing radon gas, the obvious protection was to reduce the levels of that gas through ventilation. Today, radon can be reduced in mines through improved ventilation systems to the level the NRC recommends safe for homes.
Finally, the Herald articles reported, "The Academy of Sciences says no level of radiation is completely safe. Even a small dose leads to a small increase in the risk for cancer". That interpretation of what the academy has reported is misleading. Virtually all the evidence of stochastic risks from very low radiation doses comes from straight-line extrapolations from much higher doses and not from direct observation of low-dose effects.
There have been many attempts to determine risk through direct observations by studying populations that receive dose rates moderately higher than normal. In no case have those studies shown unambiguous evidence of harmful effects. While the lack of harm found so far does not allow science to conclude that low-level radiation is safe under all conditions, it sends a warning to be skeptical of the risks from low-doses obtained from straight-line extrapolations from high doses.
There are undoubtedly many reasons why people wish to support or oppose current attempts to restart uranium mining in Western Colorado. But if anyone is planning to base their opposition on the fear that health effects like those experienced in the previous uranium boom will be repeated, the argument will be a hard sell. Specific information about the effects of radiation at different dose-levels, and new regulations and procedures to protect both uranium workers and the public from unsafe radiation exposure, can be used to demonstrate past harms need not be repeated.
Garth Buchanan holds a doctorate in applied science and has 35 years of experience in operations research.
Reach him at email@example.com.