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February 27, 1998 WQCD Letter Page 2 2. Under LA? of the draft WQCD permit (page Sj, it is stated that "The permittee has the burden of proof when requesting relief from total suspended solids (TSS), total iron and/or settleable solids limitations. Relief shall be granted only when necessary and shall not be granted when the permittee has control over the discharge...All manual dewatering of ponds that are equipped with automatic dewatering systems must meet TSS and total iron limitations. If a pond has only manual dewatering capability, relief available only to the extent required to regain necessary stability and capacity." In our January 12, 1998 letter, we stated that we supported this proposed language. On page 4 of its February 9, 1998 letter, Colowyo stated "Following the September 2 (1997) meeting with the WQCD (regarding altemate limitations for manual headgate dischazges), it was Colowyo's understanding that the WQCD was in agreement with Colowyo regarding this issue-that so long as the ponds were discharged to contain the 10-yeaz, 24-hour event, manual discharges as a result of precipitation events to maintain pond capacity would be entitled to the alternate limitations." This would seem somewhat contrary to the proposed WQCD permit. Our records indicate that all of Colowyo's ten sedimentation ponds have manual dewatering capability. All ten also have non-manual "emergency spillways" designed to safely pass the 25-year, 24-hour precipitation went without compromising the structural integrity of the pond. All but one of the ten ponds also have vertical riser pipes (automatic dewatering spillway inlets). The pond that does not have a vertical riser pipe is Outfall 003 (Gossazd Loadout Pond). In its February 20, 1998 letter DMG, WQCD indicated in its response to item A.12 of our January 12, 1998 letter that dischazges from ponds with both automatic and manual dewatering capability would need to meet primary limitations, regardless of precipitation, but that discharges from ponds with only manual dewatering capability could in certain cases be eligible for alternate limitations. We understand this to mean that at the Colowyo mine, manual dewatering from all ponds save Outfa11003 will under the new individual permit need to meet primary limitations, regardless of precipitation events, and that discharges from Outfal1003 under the new individual permit may in certain cases be eligible for alternate limitations. 3. No further comment from WQCD to DMG is necessary. Thank you. 4. No further comment from WQCD to DMG is necessary. Thank you. We.understand WQCD's statement in its February 20, 1998 letter to DMG to mean that discharges associated with precipitation or snowmelt are eligible for alternate limits for only [he first 48 hours after the "clock" starts (for rainfall events, the "clock" starts when the events end; for snowmelt, the "clock" starts when pond inflows cease), then must meet primary limits after that.