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data collected at RS-3 show the effects of natural geologic influences on the concentration of manganese. The naturally elevated concentrations of manganese recorded at RS-3 are consistent with elevated concentrations of manganese recorded in groundwater monitoring wells that have not been affected by the historic flow of groundwater from the West Pit. A seepage face located along the south bank of the Rito Seco, downgradient from the historic ESI heap leach azea, was not sampled during a recent (June 8, 2000) USEPA NPDES site inspection because the EPA personnel determined that the pooled water associated with the seepage face did nomconstitute a representative sampling location. Although, a sample from the location was subsequently collected during a site visit by an EPA representative of the Emergency Response Program, the sample was collected with reservations regarding the ability to collectG~l~a representative sample noting similaz conditions as were identified by the NPDES sampling team. Comment: II-Baseline Hazdness Value: Response: As noted above, the low hazdness at RS-1 reflects the fact that the water quality in the Rito Seco, as it flows through metamorphic bedrock, is not the same as the baseline water quality found naturally in the Rito Seco as it flows through alluvium in the downstream reach that aze more chazacteristic of flows in the vicinity of the West Pit. The issue of representative water quality collected at RS- 1, as affected by the fundamentally different geological environment, was addressed in the previous response. In addition, BMRI is surprised that the EPA would a single data point as more representative than a history of data that reflects the natural variations that would be expected from a natural environmental system, regazdless of a particulaz sampling point location. Mountain Resources, Inc. list GeoTrans 3 .rury zr, zooo