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regular maintenance of road surfaces. Recent rains have resulted in wet (and in places, muddy) <br />roads. Care should be taken to ensure continued adequate drainage and surfacing in accordance <br />with Rule 4.03.1(4) and (5). <br />Active road paving activities were ongoing near the Gossard Loadout and the main mine entry. <br />Rule 4.02: Signs and Markers <br />The stream buffer zone around Good Spring Creek is marked on the interior side of the permit, <br />but not from the exterior / County Road 13 side at the Gulch A Pond access point. There is a bare <br />T -post which may indicate a sign used to be in place here. Both the buffer zone sign and the bare <br />t -post are well within the 100 -foot buffer zone. This is not a location where equipment operators <br />are likely to conduct unapproved activities because it is difficult to access. However, improved <br />stream buffer zone signage would be advisable in accordance with Rules 4.02.5 and 4.05.18. <br />Rule: 4.05.5: Sediment Control Measures / 4.05.6: Sedimentation Ponds <br />As noted in several recent DRMS inspection reports, the shut-off valve in Prospect Pond's <br />primary discharge structure has been leaking for some time. Although this leak is not severe and <br />the valve is mostly functional, the concern is that leaks may worsen over time and the permitted <br />designs indicate that the gate valve may seal the primary discharge structure thereby providing <br />adequate detention time to treat runoff if the pond were nearly full and a design event occurred. <br />The primary discharge structure is designed with weep holes, or perforations, in a riser pipe with <br />a gate shut-off valve. Due to the location of the valve (design elevation 6,741.6'), this leak <br />appears to be similar to having a lower discharge perforation (perforation design elevation <br />6,744'). Rule 4.05.6(3)(a) requires sedimentation ponds to have adequate capacity to contain or <br />treat runoff or inflow from a 10 year / 24 hour precipitation event. SEDCAD runs demonstrating <br />the adequacy of the pond's design indicate a 1.99 hour runoff detention time based on pond <br />capacity with primary discharge perforations beginning at an elevation of 6,744'. <br />By discharging at a lower surface water elevation, this leak could effectively decrease the pond's <br />ability to contain and treat the design event. It could also render the certified as -built for Prospect <br />Pond 007 incorrect. Although this leak is currently considered minor and discharge through it is <br />negligible, this valve must be repaired to conform with approved designs before it worsens. <br />Alternatively, CCC may demonstrate that discharging at an elevation of 6,741.6' provides <br />adequate detention time to contain and treat a 10 year / 24 hour precipitation event and that a <br />shut-off valve is unnecessary. <br />The Prospect Pond was discharging through the designed primary discharge perforations at the <br />time of inspection. The open channel rock / concrete emergency spillway was in good repair and <br />would function as designed. Minor herbaceous vegetation is establishing in the emergency <br />spillway but would not appreciably impede flow under an emergency discharge situation. CCC <br />reseeded the top of Prospect Pond's embankment in March and April. Although this area is still <br />notably bare, sprouts are beginning to emerge. Grasses are well-established on the downstream <br />face of the embankment. <br />The Gulch A Pond was dry at the time of inspection. This pond has a peninsula that functions as <br />2 Pace <br />