Chapter 3—Containing Underground Nuclear Explosions © 33
Box 3-A—Baneberry
The exact cause of the 1970 Baneberry venting still remains a mystery. The original explanation postulated
the existence of an undetected water table. {t assumed that the high temperatures of the explosion produced steam
that vented to the surface. Later analysis, however, discredited this explanation and proposed an alternative scenario
based on three geologic featuresof the Baneberry site: water-saturated clay, a buried scarp of hard rock, and a nearby
fault. It is thoughtthat the weak, water-saturated clay was unable to support the containmentstructure: the hard scarp
strongly reflected back the energy of the explosion increasing its force: and the nearby fault provided a pathway
that gases could travel along. All three of these features seem to have contributed to the venting. Whateverits cause,
the Baneberry venting increased attention on containmentand, in doing so, marked the beginning of the present-day
containment practices.
Photo credit. Department of Energy
The venting of Baneberry, 1970.