Nuclear waste disposal in New Mexico and Nevada

The author describes the Waste Isolation Pilot Project (WIPP) for safely discarded nuclear wates is discussed. WIPP, now essentially complete, near Carlsbad, NM, and Yucca Mountain, in the early stages of construction northwest of Las Vegas, Nev. The WIPP was built to entomb the low-level radioactive wastes left over from US production of nuclear weapons. Yucca Mountain is envisioned as the final resting place for more highly radioactive spent fuel from nuclear power plants, but its destiny is still bitterly contested. The two projects differ in many other respects, as well. WIPP's vertical shaft plunges hundreds of meters down into ancient salt beds, where drums of trash contaminated with plutonium will be crushed and held in place by the slowly creeping salt rock. Its wastes, while a hazard if ingested or inhaled, do not emit penetrating radiation and therefore are relatively innocuous in the context of external exposure. Yucca Mountain, in contrast, has a horizontal tunnel that will lead into a repository to be mined out of the center of the mountain, only about 300 meters beneath the surface. It will be filled with highly radioactive spent fuel rods from reactors, plus "defense high level wastes". These wastes emit highly penetrating gamma radiation and must be scrupulously shielded from humans. And yet there is a case to be made that these wastes should be retrievable, at least in principle, and so plans for their repository call for the chambers holding them to be kept intact.