(AP) - Uranium is the stuff of nuclear fuel for power plants and atom bombs.
It increasingly is showing in drinking water systems in major farming regions of the U.S. West - a natural though unexpected byproduct of irrigation, drought and the overpumping of natural underground water reserves.
An Associated Press investigation in California's central farm valleys - along with the U.S. Central Plains, among the areas most affected - found authorities are doing little to inform the public at large of the risk.
Government authorities say long-term exposure to uranium can damage kidneys and raise cancer risks.
Entities ranging from state agencies to tiny rural schools are scrambling to deal with hundreds of tainted public wells.