Presentation at the National Western Mining Conference of the Colorado Mining Association, Denver, Colorado, February 7, 1959. Thank you for your invitation to discuss here today some of the aspects of nuclear explosions in mining and mineral industries. I should like this afternoon to dwell briefly upon: (1) The phenology of a nuclear explosion underground. What happens; with what energies are we concerned, and what may be the scientific and industrial results of such an explosion? (2) The safety or radiological hazards involved. If mining men hope someday to use this new and potentially useful source of packaged power, what are some of the problems we may face? First let me emphasize that the nine underground test explosions thus far have resulted in a wealth of data and interesting information which prove that radioactivity and radioactive fall-out can be completely controlled, that seismic effects are relatively minor, that appreciable amounts of heat and shock are generated, that this power might be utilized to serve a useful purpose and that the debris in an explosion area can be worked soon after the detonation.