Uranium is a naturally occurring radioactive element found in small amounts in geological formations as mineral. On Navajo Nation, the uranium found in these formations is significantly more concentrated. In a natural state, the ore is not harmful, because rock acts as a barrier to block the effects of the uranium. Uranium impacts on health primarily through inhalation, ingestion, and direct radiation exposure.

Because uranium has such a long life, the overall quantity of uranium in the earth remains almost the same, but transfers geographically through natural or human actions. When rocks are broken up, uranium integrates into the soil and can be washed into rivers or lakes.

From the 1940’s on, extensive mining and milling of uranium ore for defense and energy led to a legacy of abandoned uranium mines (AUMs). Usable uranium is extracted from the sandstone in which it is usually found by grinding it fine and leaching it with sulfuric acid. The acid carries off the desired isotopes. But the leftover waste sands or "tailings" still contain 85 percent of the ore's original radioactivity, and 99.9 percent of its original volume. There are now some 140 million tons of them scattered around the West. The acid milling liquids or liquor, also dissolve dangerous traces of thorium 230, radium 222, lead 210, and other isotopes. Because of their high radioactivity the tailings and liquor both must be isolated from the environment, but this has yet been achieved with any degree of long-term success.

Uranium-238 and its decay products, and their relational decay products, emit new radioactive elements during the decay process, including radium, radon, alpha particles, beta particles, and gamma radiation.

Health concerns associated with Alpha particles are inhaling dusts that are Alpha emitters. Once Alpha emitting dusts are inhaled, they can become lodged in the lungs and cause damage to lung tissue. Health concerns associated with Beta particles are related to the proximity to Beta sources that causes damage to living cells and tissue. Gamma rays travel great distances through air at the speed of light, and pass through several inches of tissue. They can be be inhaled, ingested, or received externally, and cause damage to internal organs.

Video

Carl Holiday, Health Physicist for Navajo AML explains the basic equipment used to detect radiation levels.

Audio

Western States Uranium Mines