Evidence of mountain top mining in the Appalachian Mountains. Photo: Library of CongressYou worry that the proposed mountaintop mining activities on Blair might have an impact on the quality of these water supplies. If the top of Blair is removed to uncover the low-sulfur coal at its center, rocks and debris will be dumped in the valley. This would fill in at least part of the river, eliminating it as a water source and destroying any aquatic life that is present.