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the Application. Groundwater seeps from the reclaimed area are collected in the West Pit Pond, • and the pond has a NPDES outfall permit (Outfa11008). NPDES monitoring reports for 1996 and 1997 described a number of self-reported discharges at this outfall in excess of permitted discharge limits; however, the Colorado Department of Public Health and Environment (CDPHE) has not determined these exceedances to be violations. The Division finds that there were 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 West Pit areas claimed for release of liability. The greater portion of the bond release area is associated with reclamation of portions of the East Pit. The area occupies the entire SEl/a, and portions of the N'/z and SW'/a, of Section 3; the SWI/4 of Section 2; a small part of the NWl/< of Section 11; and NEl/< of Section 10. It is bound by state plane coordinates N341200 to N347600 and E13530300 to 1360100. There is no ground water monitoring requirement within the areas described in the Application. Ground water monitoring in the vicinity is limited to water level measurements in a piezometer placed in an excess spoil fill known as the Streeter Fill, and, combined with surface runoff, at NPDES permit outfalls at the Streeter Pond (Outfall 001) and Gulch A Pond (Outfa11004). Construction characteristics of the Streeter Fill are found in Exhibit 6 of the Permit. Ground water within the 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 northern edge of the fill. Groundwater levels are monitored quarterly in a piezometer located in the vicinity of state plane coordinates N346200 E11360500. The steep fill slopes and well developed surface drainage system lower the quantity of water available for development of a shallow water table within the fill. The underdrain and free-draining characteristics of the spoil fill inhibit [he 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 or at the toe of the fill, or in the vicinity of the underdrain outlet (1996 AHR). Although seepage below the toe of the fill may drain to the Streeter Sedimentation Pond, dye tests have not confirmed this theory. The Streeter Fill is a valley fill. The former valley, a steep ravine, provided little opportunity for ground water recharge of formations down-dip. No aquifers were identified in the Permit that would be affected by the fill. There is no requirement in the Permit to directly monitor groundwater quality in the vicinity of this reclaimed area of the Application. The Streeter Sedimentation Pond has a NPDES outfall permit (Outfall 001). Thus groundwater seepage may be, in combination with surface drainage, monitored for quality. NPDES monitoring reports for 1996 and 1997 described a number of discharges at this outfall that exceeded the permitted discharge limits; however, none have been the subject of enforcement action by the 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 East Pit areas claimed for release of liability. 20 Apri127, 1998 This page revised May 11, 1998