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The fill and drain were proposed to be constructed by dragline utilizing a gravity segregation technique. Mine site personnel were experienced at this technique according to the revision application. The applicant had stated that the fill construction would be inspected by a registered engineer or other qualified specialist at least quarterly and during the required critical periods. However, because of the type of dragline technique that would be employed to construct the underdrain, the Division determined that inspections during the actual placement should be more frequent. the primary purpose of more frequent inspections during the time of construction was to assure that the sandstone material was sized according to the permit. These inspections would also assure that there was no contamination from shale, coal or clay, and that the drain was being constructed to function as designed. Therefore, a stipulation was attached to the revision approval requiring that "A QUALIFIED REGISTERED ENGINEER SHALL PERFORM INSPECTIONS AT LEAST BIMONTHLY DURING THE CONSTRUCTION AND PLACEMENT OF THE UNDERDRAIN. RECORDS OF THE INSPECTIONS ARE TO INCLUDE DATE, TIME, INSPECTOR AND OBSERVATION. COPIES SHALL BE RETAINED AT THE MINE SITE. AFTER COMPLETION OF THE UNDERDRAIN CONSTRUCTION, COPIES OF THESE INSPECTION REPORTS SHALL BE SEN7 TO THE DIVISION." The fill underdrain inspections were conducted on a bimonthly basis and inspection reports sent to the Division as required, thereby resolving the stipulation. The existing drainage in the area of the valley fill emptied into a closed basin. Upon reclamation, PCC proposed to re-establish drainage on the valley fill to flow to an existing channel and then into the Wadge Impoundment. This would improve surface water drainage and act to help eliminate seepage of water from the closed basin into adjacent spoils. The channel had been designed to adequately handle flows, however, velocities were determined to be high. Based upon erosion occurring in the existing channel and the Division's flow velocity calculations, erosion would be a problem in this channel. Therefore, a stipulation was attached to the revision approval requiring that "WITHIN 90 DAYS OF REVISION APPROVAL, THE APPLICANT MUST SUBMIT A DETAILED PLAN FOR EROSION CONTROL USING RIPRAP, EXCELSIOR MATTING OR OTHER MEASURES TO BE IMPLEMENTED DURING CHANNEL CONSTRUCTION." An acceptable erosion control plan was received by the Division within the required time frame, thereby resolving the stipulation. Wadge Area All areas affected by mining in the Wadge East pit, Wadge West pit, and "Left open" Wadge pit will be returned to approximate original contour as shown on Exhibit 12-g. The proposed post-mining contours shown on Exhibit 12-9 were approved by the Division at the time of issuance of the initial 5-year permit. The Division finds that the proposed topography depicted on Exhibit 12-9 meets the requirements for approximate original contour as defined by the Regulations for operations to be conducted during the second permit term.