In her new book "Yellow Dirt," Judy Pasternak writes of a harrowing tale from Navajo country: how the U.S. government allowed uranium companies to walk away from hundreds of radioactive mines across the reservation. Not told of the danger, Navajos built their homes from the leftover ore and tailings. As Pasternak tells LOE's Steve Curwood, four generations of people were sickened and are still being buried.