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1.
a.k.a. "Slag heap." A boney pile is a mound of coal waste, sometimes the size of a large hill and indistinguishable from rolling hills around it. "Boney" is the waste itself, also known as "slag."
"They've reduced the boney pile in Revloc and now you can see the town from the highway."
by Edenza February 27, 2008