Uranium is a natural, radioactive element that is mined from the earth. It is extracted from ore by a process called milling. Uranium tailings are the radioactive, sand-like materials left over from uranium milling.

 

Uranium tailings are placed in mounds called tailings piles, which are located close to uranium mills. There is one abandoned tailings pile in Pennsylvania. All the other tailings piles in the United States are in the West or Southwest.

 

Demand for uranium has declined due to a lack of demand for new nuclear power plants and increased uranium imports from other countries. Most of the 26 licensed U.S. uranium mills no longer process uranium, and another 24 sites are abandoned.

 

Uranium tailings and uranium waste contain radium, which stays radioactive for thousands of years. Many of the radioactive products in uranium tailings and waste produce gamma radiation. The radioactive decay products in tailings pose a health hazard to people in the immediate area of the tailings. Tailings can also contaminate surface water or groundwater that may be used for drinking water. Tailings can also contain selenium and thorium.

 

Radium decays to produce radon, an invisible and odorless radioactive gas. Radon is a carcinogen that can cause lung cancer. Radon from uranium tailings and uranium waste can threaten human health in several ways. People can be exposed to radon gas indoors if tailings are misused as construction material or backfill around homes or buildings. Piles of uranium tailings and uranium waste also can release radon gas into outdoor air or small particles from tailings can be blown into the air for people to inhale or ingest.

 

Because uranium occurs naturally, small amounts of uranium are found everywhere, including in air, food, and water. Some uranium is released from the erosion of uranium tailings.

 

People who live near uranium mines may have an increased risk of kidney disease. Large amounts of uranium in the drinking water can react with the tissues in the body and damage the kidneys.

Navajo lands in the Four Corners area (New Mexico, Arizona, Utah, and Colorado) of the Southwest are rich in uranium. From 1944 to 1986, uranium was extracted from these Navajo lands. Many Navajo people worked in the mines and lived nearby with their families. Some miners were exposed to high levels of radioactivity in uranium mines and mills.

Uranium mills on Navajo lands included the 230-acre Shiprock Mill in New Mexico. Private companies leased the site from the Navajo Nation from 1954 to 1968. In 1983, the Navajo Nation and the U.S. Department of Energy agreed to a cleanup plan for the site. The site met federal cleanup standards in 1991.

The largest accidental release of radioactive material in U.S. history occurred in 1979 at the Church Rock site on Navajo lands in New Mexico. A dam holding uranium tailings burst and sent tons of radioactive waste and contaminated liquid into the Rio Puerco River.

The Navajo still cannot use this water. The Northeast Church Rock Mine is the Environmental Protection Agency’s highest priority for cleaning up abandoned uranium mines.

This description is based on the information found in the Web links listed with this topic.