2012-09-26_INSPECTION - C1981010 (2)

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September 19, 2012 C- 1981 - 010 /Trapper Mine MLT • Riprapped channels have been constructed along both sides of the fill (Photos 2 and 3). The channels appear to be stable and well maintained, although flow seems to have caused some shifting of the rocks lining the west channel. • The outer slope of the fill appeared to be stable, with no rills or gullies having developed. • Revegetation of the older (lower) portions of the slope has been accomplished. Those areas seeded more recently (upper slope) exhibited a high percentage of annual weeds, such as Lambsquarters, mustards and knotweed; the western portion of the upper half was dominated by Russian thistle. (Photo 4) • Individual first -year Houndstongue plants were scattered across the slope, and a few Musk thistle rosettes were observed. Control efforts on these noxious weed species should be continued. • The downstream end of the underdrain was visible, extending beyond the toe of the Horse Gulch Fill. Mr. Nicholson said a trickle of water perpetually flows from the underdrain, creating a small pool (Photo 5). EXPLOSIVES — Rule 4.08 Distance Prohibitions 4.08.4; Warnings 4.08.4; Control of Adverse Effects 4.08.4: At 2:30 p.m., we saw a crew preparing for a shot in K -Strike Pit, at K3 Road. The blast occurred at 3:25 p.m. (Photo 6). • Warning sirens were sounded prior to the blast, and the all -clear signal was given afterwards. FISH and WILDLIFE — Rule 4.18: • A herd of seven Pronghorns was sighted on the eastern side of the Horse Gulch Fill (Photo 7). The animals disappeared over the ridge to the north. Some bear scat, probably left by a cub, was seen near the western side of the Horse Gulch Fill. HYDROLOGIC BALANCE - Rule 4.05 Drainage Control 4.05.1, 4.05.2, 4.05.3; Siltation Structures 4.05.5, 4.05.6; Discharge Structures 4.05.7, 4.05.10; Diversions 4.05.4; Effluent Limits 4.05.2; Ground Water Monitoring 4.05.13; Surface Water Monitoring 4.05.13; Drainage — Acid and Toxic Materials 4.05.8; Impoundments 4.05.6, 4.05.9; Stream Buffer Zones 4.05.18: The West Pyeatt sediment pond was being mucked out by an excavator with a long boom (Photo 8). The muck was placed into a haul truck and then transported to the Ashmore pit for disposal. The East Pyeatt drainage was being reconstructed. Check dams constructed of larger rocks are set in place prior to smaller riprap being placed to line the channel (Photo 9). Mr. Nicholson explained that the check dams serve to trap the sediment as the runoff flows downstream. Number of Partial Inspection this Fiscal Year: 2 Number of Complete Inspections this Fiscal Year: 1 Page 3 of 10