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r In regard to item A, the Division pointed out that we are concerned that water appazently had to be retained in Prospect Pond in July, 1995 for nearly three weeks. before it could be discharged and meet effluent limits. Obligating most of the pond's storage capacity for such an extended period of time does not adequately address the regulatory requirement to maintain ponds to contain or treat runoff to comply with CDPES effluent limits (Rule 4.05.6(3)). Colowyo indicated during our meeting that they preferred to rely on pond designs which are intended to contain, rather than treat, storm runoff. The regulations do offer the option of containing or treating runoff from the mine area. However, in order to maintain capacity to contain or treat runoff, Colowyo also needs to be able to manage the water level in the pond in a timely manner. The Division typically requires pond capacity be restored within 36-72 hours following inflow from a storm event or snowmelt. If pond inflow occurs while the pond is full of water Colowyo will have no option but to manually discharge water from the bottom of the pond or risk having dischazge through the emergency spillway. Either of these options is likely to result in noncompliance, as apparently occurred at the Gulch A pond in February. Please explain, in the permit application package, how the water level in sediment ponds will be will be lowered from the top of the primary riser in order to contain or treat runoff from a 10-year, 24-hour storm event, in compliance with Rule 4.05.6(3). In regard to item B, Colowyo re-submitted a portion of the SEDCAD run depicting the actual spillway elevations of the East Taylor Pond. The revised SEDCAD run, noting the change in spillway elevations, revealed that the peak stage of the 10-year, 24-hour storm event would discharge through the emergency spillway if the pond contained water to the elevation of the primary riser. The revised SEDCAD run does not comply with Rule 4.05.6(4), which states that there shall be no out-flow through the emergency spillway during the passage of runoff resulting from the 10- year 24-hour precipitation event. Please explain how water in the East Taylor Creek Pond will be managed to comply with Rule 4.05.6(4). 11. Question number 4 of the letter requested that Colowyo identify the use of trash racks on a number of ponds in the permit area. Please identify which ponds will contain a trash rack over the primary spillway. Miscellaneous 12. Well sampling procedures was another topic discussed at the meeting. It was noted by Colowyo personnel that wells have been sampled for total recoverable metals rather than total dissolved metals. Both the Division and Colowyo agree that a sampling procedure change to dissolved metals is warranted, and needs to be documented in the permit application and in the annual hydrology report (AHR).