spoil bank
n.β Β«In the rolling hills just a few miles outside town, a forest of black locust, black cherry and young sugar maple grows from what the locals call spoil banks, mounds of dirt and rock tossed aside by years of strip-mining.Β» ββQuoth the raven: βIβm backβ” by Kevin Mayhood in Wintersville, Ohio Columbus Dispatch (Ohio) May 20, 2008. (source: Double-Tongued Dictionary)