In 1979, a dam at a uranium mine collapsed. More than 90 million gallons of radioactive waste shot down the Rio Puerco.
It was the largest release of radioactive material in United States history. And it happened in Church Rock, on the Navajo reservation in northwestern New Mexico.
No comprehensive health studies were done to learn how the spill might have affected people living nearby.
Now, Reps. Ben Ray Luján, Edward J. Markey, Henry A. Waxman, and Frank Pallone are asking for a formal update on a study that Congress authorized four years ago.