A clearing in the Carson National Forest, about twenty-five miles south-west of Dulce, is marked with a small plaque reading:
SITE OF THE FIRST UNITED STATES UNDERGROUND NUCLEAR EXPERIMENT FOR THE STIMULATION OF LOW-PRODUCTIVITY GAS RESERVOIRS. A 29 KILOTON NUCLEAR EXPLOSIVE WAS DETONATED AT A DEPTH OF 4227 FEET BELOW THIS SURFACE LOCATION ON DECEMBER 10, 1967.
The detonation, part of the ‘Plowshare Program’ for the peaceful use of nuclear explosions, did succeed in part, creating an eighty-foot wide, 335-foot high, natural gas-filled cavity. Unfortunately the gas was rendered dangerously radioactive by the explosion and had no commercial value, so the site was sealed up for eternity.
Mirage Men A Journey into Disinformation, Paranoia and UFOs (Mark Pilkington)