[IronJack]

I was working on the Western Slope when the shale boom hit the Parachute Valley in Colorado in the early 80s. It was a phenomenon. Cities literally sprang up overnight, and an army of heavy machinery moved in to turn mountains into molehills and open a path to "the rock that burns."

Then, one weekend, Exxon pulled the plug. Shut down the entire operation overnight. All that time and energy and material went for naught. Zilch. Bupkus. And the governor was afraid he'd have to call out the National Guard to suppress riots from the displaced workers (he didn't).

[Eric in the Ozarks]

The coarse reject material (shale after oil removed) becoming 55 percent larger was something no one expected. If Exxon had a couple of mining people on the payroll they could have predicted much of this.
I was mining coal in the early 80s. Drilling and blasting the overburden, stacking via dragline and then dozing with a D9L would result in a higher topography, even if 6 feet of coal had been removed.
This was hard to explain to the uninitiated.
If we mined into a hillside and the cover got deeper as we advanced, we could be out of fill at the top of the hill...