To mining engineers, oil shale had presented an as yet unsolved and completely unambiguous problem: how to remove the shale without destroying the face of the earth. So far, three principal methods had been considered. One was to strip-mine it, crush it, separate the oil, then smooth out the tailings-a process that could result in the absolute rearrangement of twenty-five thousand square miles. Another was to go underground, excavate a percentage of the rock, and refill the caverns with tailings. That was known as the “modified in situ” approach. And finally someone thought of drilling a hole, pumping in propane, and starting a fire. The heat would cause liquid oil to run out of the shale. The oil could be forced up through zakelijke energie vergelijken another well before the fire destroyed it. A bum would not, like a clinker fire, continue indefinitely. If oxygen was not fed to the flames, they would die. This was known as “true in situ” mining; and there in White Mountain, a few miles away, the federal government had been perfecting the technique. The experiments thus far had brought down the recovery cost to a million dollars a barrel. In Cheyenne one time, I saw a Peter Pan Crunchy Peanut Butter jar filled with such oil. It looked and smelled like the contents of a long unemptied spittoon. The one-and-a-half-trillion-barrel estimate was somewhat extravagant, because it included every last drop-referring, as it did, to all shale with any content of kerogen. In the richer rock-in the shales that contained from twenty-five to sixty-five gallons of oil per ton-were no more than six hundred billion barrels. That would do. That was more petroleum in place than all the petroleum produced in zakelijke energie the world to date. Love remarked that oil shale had been “trumpeted to the skies” but, with the energy crisis in pe1igee, both government and industry were losing interest and pulling out. Temporarily pulling out. Sooner or later, people were going to want that shale.