It’s a sunny October day on the outskirts of the west German town of Bottrop. A quiet, two-lane road leads me through farm pasture to a cluster of anonymous, low-lying buildings set among the trees. The highway hums in the distance. Looming above everything else is a green A-frame structure with four great pulley wheels to carry men and equipment into a mine shaft. It’s the only visible sign that, almost three quarters of a mile below, Germany’s last hard coal lies beneath this spot.