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The 136.9-acre Section 16 Pit reclaimed region of the bond release area is located primarily in the • E'/z of Section 16 and W'/z of Section 15, T3N R93W, in the vicinity of state plane coordinates N332500 to N336500 and E1349000 to E 1353400, and includes the Section 16 Pit Fill, an excess spoil fill. Construction characteristics of the Section 16 Pit Fill are found in Exhibit 19 of the Permit. The potential for ground water within the excess spoil Section 16 Pit Fill is minimized by construction characteristics of a fill underdrain, steep fill slopes (no greater than 3 horizontal to 1 vertical), and surface drainage terraces at approximately 100-foot intervals that lead to a perimeter relief drain on the southern edge of the fill. Groundwater levels in the excess spoil fill are monitored quarterly in a piezometer located in the vicinity of state plane coordinates N334600 E11351900. However, this monitoring is related to fill stability rather than to ground water quantity or quality. The steep fill slopes and well developed surface drainage system lower the quantity of water available for development of a shallow water table. The underdrain and free- draining characteristics of the spoil fill inhibit the development of an elevated water table. The results of piezometer monitoring indicate that the level of the ground water table is in the vicinity of undisturbed materials underlying the rock underdrain. No springs or seeps have developed on the face of the fill. No aquifers were identified in the Permit that would be affected by the fill. There is no requirement in the Permit to monitor groundwater quality in the vicinity of this reclaimed area of the Application. Any groundwater that might seep from the reclaimed area would be collected in the Section 16 Pond or Prospect Pond. Both ponds have NPDES outfall permits (outfall 009 at the Section 16 Pond and outfa11007 at Prospect Pond). Thus any seepage of groundwater would, in combination with surface drainage, be monitored for quality. NPDES monitoring reports for 1996 and 1997 described a number of self-reported discharges at outfa11007 that exceeded permitted discharge limits; however, none were subject to enforcement action by the Colorado Department of Public Health and Environment (CDPHE). The Division finds that there are no adverse effects of surface mining activities on the quantity and quality of water in ground water systems, on the recharge capacity or ground water systems, nor on the hydrologic balance from surface water discharges in the Section 16 Pit areas claimed for release of liability. Monitoring of surface water was evaluated to determine [Rule 4.05.13(2)] the impact on the hydrologic balance [Rule 2.05.6(3)(iv)]. All runoffs from disturbed areas are discharged from the Permit area at CDPHE (NPDES) outfalls as described above. Discharges were as previously discussed. The Division finds that there were no adverse impacts on the hydrologic balance with regards to surface waters. In addition to the NPDES discharge points, Colowyo monitors for potential effects of the mining operation on the adjacent surface waters of Goodspring Creek at the New Upper Goodspring Creek monitoring station to characterize conditions found upstream of mining activity. A Lower Goodspring Creek site is monitored to characterize conditions found downstream of mining activity. A Taylor Creek site is monitored to characterize conditions found downstream of the West Pit mining area and the Gossard Coal loadout facility. A review of Annual Hydrologic Reports up through 1997 found no changes in water quality due to mining activities. • 21 April 27, 1998