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ROCKCASTLE COMPANY <br />Grassy Gap Mine <br />Sediment Pond Inspection <br />INTRODUCTION <br />On Friday, June 28, 1991 Thomas Leidich and Robert Peterson visited the Grassy <br />Gap Mine and completed a thorough inspection of Sedimentation Ponds 2, 3, 4, and <br />5/6. The ponds were inspected for structural weakness, erosion, and other <br />hazardous conditions. The inspection also included sediment level surveys. Surveys <br />of sediment levels were executed utilizing a hand level and survey rod. Following are <br />the results of the pond inspections. <br />POND 2 <br />Pond 2 is an incised pond located on the west side of reclaimed Pit 2. Pond 2 has <br />two primary inlets and one outlet, an incised trapezoidal channel, which serves as an <br />emergency spillway. The entire pond was inspected. There is limited vegetation on <br />the pond side slopes but no significant erosion was observed. The side slopes <br />appeared stable with no signs of cracks, slides or seepage. There was no standing <br />water in the pond but the bottom was muddy. The riprapped outlet structure appears <br />stable with no evidence of recent discharge. <br />The sediment level was approximately 10 feet below the invert of the spillway. The <br />accumulated amount of sediment is negligible compared to the capacity of the pond. <br />POND 3 <br />Pond 3 is an incised pond located on the west side of reclaimed Pit 3. Pond 3 has <br />two primary inlets and one outlet, an incised trapezoidal channel, which serves as an <br />emergency spillway. The entire pond was inspected. There is limited vegetation on <br />the pond side slopes however, no significant erosion was observed, The side slopes <br />appeared stable with no signs of cracks, slides or seepage. There was approximately <br />