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It is further stated in the second paragraph on Page 8 (Part V.B.1) that "the previous permit stated that all manual discharges must meet primary limitations. This was based on the presumption that manual discharges can be accomplished in such manner that primary limitations could always be met. While this may be true for facilities with automatic dewatering structures, it is not necessarily true for facilities such as this one that have no other option under normal circumstances than to manually empty a pond." It is further stated on Page 8 that "the permittee has reassessed their sedimentation pond system and proposed to convert most or all to the automatic dewatering mode." As mentioned earlier in our memorandum, Colowyo's ponds are currently designed to pass and treat the l0-year, 24-hour precipitation event. These ponds are thus currently designed for "automatic dewatering", in that the l0-year, 24-hour precipitation event is designed to discharge through the pond's primary spillway. These ponds additionally have a secondary spillway, which is designed to safely pass the 25-year, 24-hour event. These ponds may be additionally equipped with manually-operable discharge tubes: however, dischazges through manually-operated dewatering tubes are not currently designed to meet a~ effluent limitations. 2. We support WQCD's statement in the first paragraph on Page 10 of the Summary of Rationale that reads, "All manual dewatering of ponds that are equipped with automatic dewatering systems must meet TSS and total iron limitations." We strongly support additional language requiring Colowyo to sample every manual discharge for the purpose of demonstrating that the discharge meets the TSS and total iron limitations. C. Colowyo's September 30, 1997 "Comments on Draft CDPES Permit and Rationale" Colowyo, in their Subsection 1 under their Section "Rationale Document", states that "the numbers used in the table are subject to continuous revision and are, in fact, inaccurate for the containment scenario under which the ponds are currently operated". We repeat: Colowyo's ponds are currently designed to allow the ]0-year, 24-hour precipitation event to pass through [he pond's primary spillway and meet the settleable solids criteria. If Colowyo is operating these ponds under a different scenazio, discharges that occur from these ponds under that different scenario have not been designed to meet any effluent limitations. 2... On page 2 of the September 30, 1997 memo, Colowyo states in Section "4.IV.A.2., Sources to the Treatment Plant, Rationale Page 3" that "a significant portion of water at the Colowyo facility is surface runoff that flows by gravity into the pit and, in tum, out of the pit. No pumping is involved." Yet, immediately after this statement, Colowyo requests the WQCD permit Rationale language to read "Once water enters a pit and is subsequently pumped out, it is considered pit pumped water..." {Colowyo's emphasis).