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Inspection Report <br />Page 4 of 4 <br />(see attached photograph 2). See also photograph 2.a in Attachment C (SJBHD inspection report), and <br />photograph 1 in Attachment D (DRMS inspection report);. <br />ii. Disturbed access road to May Day Level 1-at the approach to the Level 1 facility (see attached <br />photographs 4 and 5); <br />iii. Disturbed access road to Chief portal and May Day Lamb-along the approach to the Chief portal and <br />the May Day Lamb facilities (see attached photographs 6, 7, and 8). <br />In locations where BMPs had been implemented for cut and fill slopes, they were not installed in accordance with <br />good engineering practices or publically available installation specifications, and were not properly maintained to <br />function as intended. Specific locations identified during the inspection include: <br />New access road off County Road 12 <br />a) Silt fence BMPs implemented at the upper portion of the new access road before the switchback (see <br />attached photograph 9) and the upper portion of the road adjacent to the La Plata River after the <br />switchback (see attached photogrraph 10) were not trenched in and not maintained (had pulled off <br />stakes; fencing material lying on ground). Standard installation details for silt fence require <br />entrenchment and maintenance. Additional photographs of silt fence BMPs requiring maintenance <br />(photographs 2.b through 2.f, and 2.h) are provided in Attachment C (SJBHD inspection report), and <br />in photographs 2, 3, 6 and 7 in Attachment D (DRMS inspection report); <br />b) The straw mulch BMP implemented on fill slopes of the road adjacent to the La Plata River (see <br />attached photograph 11) was not crimped in or uniformly distributed across the fill slope. Standard <br />installation details for straw mulch require crimping and uniform distribution to provide immediate <br />protection against raindrop erosion. Additional photographs of inadequate application of straw <br />mulch are provided in photographs 2, 3, and 7 in Attachment D (DRMS inspection report for the <br />Idaho Mill and Idaho Mine) <br />As a result, there was a potential for erosion of the cut and fill slopes and transport of sediment from these slopes <br />to Little Deadwood Gulch (State waters and tributary to the La Plata River) and the La Plata River and wetlands <br />area located downgradient of the roads (State waters). Adequate BMPs must be implemented for cut slopes to <br />control water run-on to the slope and to stabilize the disturbed slope itself to prevent erosion and the <br />discharge of sediment from the disturbed slope area. Adequate BMPs must be implemented for fill slopes <br />for slope stabilization, and perimeter control as appropriate, to prevent erosion and the discharge of <br />sediment from the disturbed slope area. All BMPs must be installed and maintained to function as <br />intended. <br />c. Road crossings of drainages: It was noted during the inspection that inadequate BMPs were implemented to <br />manage stormwater runoff from disturbed areas associated with the culvert used in the road crossing of an <br />unnamed drainage to the La Plata River. The road crossing was located on the portion of the new access road <br />adjacent to the La Plata River and wetlands area. Specifically, the cribbing BMP used to stabilize the disturbed <br />area around the culvert crossing was in disrepair and had fallen down the downgradient slope of the crossing, and <br />the disturbed area around the culvert was not stabilized to prevent the discharge of sediment from the disturbed <br />slope area to the drainage way (see attached photographs 12, 13, and 14). As a result, there was a potential for <br />discharge of sediment from the disturbed area to the adjacent La Plata River and wetlands area (State waters). <br />Culverts used in road crossings must be sized appropriately to accommodate the upslope drainage volume, <br />and designed and installed to prevent upgradient and downgradient scouring of the drainage (energy <br />dissipation BMPs). In addition, adequate BMPs must be implemented for disturbed areas adjacent to the <br />installed culvert to prevent erosion and sediment discharge from these areas into the drainage and culvert.