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including specific inspection criteria under Rule 4.05.9(15). A copy of completed inspection forms will be provided to the CDRMS, and a copy will be retained on-site and will be available for inspection and review by authorized persons. If observations during an inspection indicate that a potential hazazd exists, the CDRMS will be promptly notified of the potential hazard and of any appropriate emergency procedures formulated and/or implemented to protect public safety and remediate the potential hazard. On completion of operations, it is anticipated that the Area 1 Basin will be reclaimed, as described under Section 2.05.4(2)(c) of the PAP. Reclamation will involve backfilling the basin area with either coal waste or spoils, placement of a minimum of 4 feet of suitable spoil (if used for coal waste only), topsoil replacement, and revegetation. Spoil Spring Discharge, Ground Water Movement, and Ouality Considerations The Area 1 Basin is designated as a coal waste disposal site, has been used for coal waste disposal in the past, and may be utilized for this purpose in the future. When the coal preparation plant was constructed and commissioned, however, all coal waste previously placed in the Area 1 Pit was removed and run through the wal preparation plant to recover the associated coal. The Area 1 Pit is an open excavation with a bedrock highwall on the north and west sides and a spoil slope on the south and east sides. The bedrock on the highwall side contains a sequence of saturated sandstone and siltstone units referred to as the "overburden aquifer". The chazacteristics of the overburden aquifer aze fully described in the PAP text under Section 2.04.7. The permeability and storativity of the overburden aquifer have been determined by conducting pump tests at several locations in the permit area. At the Energy No. 1 Mine, average horizontal permeability is 2.9 gallons per day per square foot, vertical permeability is 0.1 gpd/ftz, and storativity is 1.7 x 10-4 (unit-less). The average yield of wells penetrating the overburden aquifer is 17.6 gpm. Hydraulic conductivities in the overburden aquifer are, therefore, very low, except in localized areas where the aquifer has been extensively fractured by joints and faults. The reclaimed spoil material up-dip from the pit forms an unconfined aquifer which serves to recharge the local ground water system. Water from snowmelt and rainfall infiltrates into the spoils to the floor of the former mine pit and then moves down-dip along the pit floor where it tends to pool against the highwall. Based both on calculated values and previous monitoring of this area, inflows to the Area 1 Basin from spoil spring discharge aze estimated at a maximum of approximately 35 gpm, with peak spoil spring discharge occurring during a brief period (a few days to a maximum of two months) during late spring. Since the Area I Basin is at the final highwall, the limited volume of water resulting from infiltration through the spoils water tends to collect and accumulate in the pit. The head of any spoil water accumulation in the pit normally exceeds the elevation of the piezometric surface in the adjacent overburden aquifer, consequently spoil water accumulations infiltrate into the highwall, providing rechazge to the overburden aquifer. From this azea, ground water flows to the north under the gradient of piezometric surface as shown on Map 13, Twentymile Pazk Hydrology. Strip mining operations at the Energy No. 1 Mine ceased in 1980. During the mining operations, groundwater inflow from the overburden in the highwall was minimal. Since that time, infiltration of water from rainfall and snowmelt into the reclaimed spoils has ceased leaching of the spoil materials, and this leachate has accumulated in the final pit at the bottom of the dip-slope. The chemistry of the leachate water, as well as the water level and chemistry of ground water in the overburden aquifer, were monitored on a monthly basis during afive-yeaz period from 1979 through 1983. Monitoring records are listed in Table 50, Energy Mine No. 1 Pit Water Quality, of the PAP. As shown below, actual concentrations of TDS fluctuate, due to seasonal variations in snowmelt and precipitation: TR07-59 Ex8V-2 02/27/07