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-' • ( Page 2 ) • MINE ID # OR PROSPECTING ID # M-77-342 INSPECTION DATE 11/3/99 INSPECTOR'S INITIALS ACS OBSERVATIONS This inspection was conducted to follow up on certain issues identified :.n the Division's 5/24/99 inspection of the ore conveyor corridor. In particular, topsoil stockpile stabilization and storm water management practices in the conveyor corrido:c were inspected. The following observations were made. The largest pile of topsoil salvaged during construction of the ore conve~~or is located at the north end of the East Branch Reservoir and is adjacent to the County Road. This pile has been regraded and hydroseeded/mulched since the 5/24/99 inspection. "he steepest side slope observed on the pile is on the north side and was measured using an Dabney level to be very close to 3:1. Germination of grass over virtually the entire pile was observed. Signs identifying the stockpile as "reclamation soil" have been installed. Silt fence is in place along the down gradient north and east pile perimeters. Approxinately 10 percent of the silt fence was down and will require maintenance before winter. At the time of the 5/29/99 inspection there were two topsoil piles located on either side of the road at the south end of East Branch Reservoir. The topsoil pile on the west side of the road was wetlands soil and has been completely removed for use in the constructed wetlands. The pile on the east side of the road has been regraded, hyd:=oseeded/mulched, and had "reclamation soil" signs installed. The steepest slope measured cn the pile is on the back or east side and is very close to 3:1. Grass germination on the stockpile was observed. The 4-culvert fill slope crossing of the East Branch of Ute Creek was inspected. The silt fence and hay bale installations at this location were complete, properly installed and in good condition. The Operator has installed a catch basin and riprap run town at the south end of the drainage crossing fill. This structure will convey runoff from the conveyor alignment and the steep slope bypass road down onto the East Branch drainage. The runoff exiting the riprap rundown is passed through two small catch basins and a row of silt fence before it enters the East Branch drainage associated wetlands. The silt fE~nce may be under considerable pressure at this point during snowmelt, and must be inspected regularly. Similar riprap rundown structures have been placed on other fill slopes along the corridor where it has been observed that runoff concentration was causing erosion. In general, the storm water management practices observed along the conveyor corridor are well thought out and properly installed and maintained. In locations where storm water or runoff will be concentrated, best management practices such as hay bale installations are installed to filter the water prior to discharge to undisturbed areas. The down gradient perimeters of most disturbed areas are surrounded by silt fence. The steep roadside ditches near Station 124 have been provided with a series of rock check dams. Runoff from the steep slope between Stations 80 and 85 is routed into water bars with integrated perforated pipe subdrains. Discharge from the subdrains flows to a serifas of silt fence installations aligned perpendicular to the slope along the east side of the conveyor. All disturbed areas in the conveyor corridor other than the road surfaces have been seeded and mulched. It should be noted that the summer of 1999 exhibited much higher than normal precipitation at the Henderson Mill. By observing runoff patterns during heavy precipitation events, the Operator has been able to tailor the storm ~Nater management facilities to manage the runoff. The south access road was inspected. The upper part of the road has been incised to form a canyon. To manage runoff through this section, the road has been constru•=ted on a french