It was December, 1961, in the desert just southeast of Carlsbad.
Tufts of dry grass bent low beneath a winter wind, sand swirled across a desert plain, and here and there a tumbleweed rocked against a juniper. Men with hardhats and clipboards walked around reading instruments, ducking into equipment sheds, and taking notes.
For several months, they had been digging.
The men had dug a deep shaft, ten feet wide and 1,184 feet deep. They had dug a horizontal tunnel from the bottom of the shaft, 1,116 feet through an ancient salt bed. And they had drilled a narrow hole, directly down to the tunnel’s end.
In the days approaching their final day in the desert, the men attached their reason for being there to a long, steel cable, and threaded the cable down to the bottom of the hole, until the hole met the end of the underground tunnel. After that, they sealed the hole shut with concrete and epoxy, and soon, they gave an order.
A signal then zipped down the cable, and at the cable’s end, a nuclear bomb exploded.
It was twelve p.m., December 10th, 1961.
The underground explosion contained the destructive equivalent of 3,100 tons of dynamite. It shook the earth above and collapsed the tunnel leading into it. Its blast should have been contained by the tunnel’s collapse, but the main shaft soon began venting dense smoke and radioactive steam, and the outpouring continued for over thirty minutes, only five miles from the much-traveled Highway 128.
Six months later — according to Gerry Taylor, a board member of Albuquerque’s National Atomic Museum — the blast’s most intense radiation had dissipated, and the men of the Atomic Energy Commission (AEC) returned to the site. They descended the main shaft, moved through the reopened tunnel, and found that the over-2,000˚ Fahrenheit nuclear blast had melted the rock salt around it in all directions and created an enormous, swelteringly hot, “molded glass” cave, 170 feet across and 80 feet high. The rock of the manmade cave had been altered in an unprecedented and instantaneous act of geologic metamorphism, the walls of the cave shone blue and green and violet and, the New York Times of March 8th, 1963 later noted, they were studded with newly made muscovite, a flaky mineral normally formed over millions of years.
The explosion was known as Project Gnome, and was the first step of America’s much larger Operation Plowshare — a bizarre attempt of the AEC’s to explore the peaceful purposes of underground nuclear explosions. Project Gnome was conducted in the hope that a nuclear explosion in a salt environment would result in stored heat that could be used to boil water to generate steam for electricity. Other ideas envisioned — but fortunately never attempted — as part of Operation Plowshare included using 300 hydrogen bombs to widen the Panama Canal, blasting an artificial harbor next to an Inupiat village in northwestern Alaska, and connecting underground aquifers in Arizona.
Yet another idea was to use an underground nuclear explosion to shatter subterranean rock and thereby stimulate the flow of natural gas. Named Project Gasbuggy, this idea was tested, on December 10th, 1967, in New Mexico. The explosion was about sixty miles east of Farmington and about fifty percent larger than the bomb dropped on Hiroshima, Japan.
“The bomb exploded,” Wade H. Nelson wrote in a 1999 Durango Herald article. “Closed circuit television cameras on site recorded a seven-foot ground wave — the ground and trees and everything in the vicinity rising and falling like an ocean wave.” The experiment produced unheard-of amounts of natural gas in the area, but all of it was radioactive, and no one would buy it. The blast also created another enormous cavern, although this one collapsed within seconds.
Project Gnome’s cave, however, is one of the few such caves to remain intact, and still lies dark and hot and empty beneath the desert above it. Also surviving, near Carlsbad and near Farmington, is an undying amount of toxic radiation.