Click on image to view larger version.
Fig. 1. (A) Site location of the Roberts–Dawson mine. (B) Each ground water sampling site contains a cluster of three wells; one in the upper Freeport Sandstone, one in the middle coal layer, and one in the lower Clarion Sandstone. (C) Surface water and ground water sampling locations relative to known mine voids at the Roberts–Dawson mine site. Shaded regions represent areas in the mine voids where high-strength stabilized flue gas desulfurization (FGD) was placed. Low-strength stabilized FGD was injected into the unshaded regions of the mine voids. The direction of flow in the receiving stream is indicated by a Q.
