_GENERAL DOCUMENTS - C1981017 (249)

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first two bolts. Due to the severity of the gully, a gap of about twelve inches existed between the base of the third (horizontal) roof bolt and the base of the gully. This space was choked with large rock wedged between the ground and the roof bolt. The entire concavity formed immediately uphill of the three roof bolts and rock was then filled with straw. The first trap was constructed about ten feet above the second trap. The concept behind the traps was to construct a shelf within the gully where water rushing down slope would lose velocity and deposit sediment scoured from the base of the gully above. This would decrease the overall slope gradient, and allow for areas in which vegetation could become established, which in turn would help to stabilize the gully. Unfortunately, the sediment traps were covered by spray-on erosion control matting during the subsequent Soil Guard test. The value of the traps without the use of other erosion control treatments cannot be measured. However, it is thought that the relative effectiveness of the traps may still be evaluated, and conclusions regarding additional construction of sediment traps of this nature may be made. RECOMMENDATIONS FOR FUTURE RECLAMATION EFFORTS Old Refuse Pile Drainage Currently, drainage from the Old Refuse Pile flows to sediment ponds located on the north side (one at Dutch Creek Level, and one at the mid-elevation of the pile) and one at mid-elevation on the east side. After vegetation has become sufficiently established to control erosion, permanent drainage channels should be constructed so that the ponds may be decommissioned. It is currently thought that the best way to do this is to build the drainages along the existing roads on the facility. The drainage construction effort may be undertaken at the time of the facilities area reclamation. Revegetation Bid For Outslopes The bids for Mines 3 , 4, and 1/2 contemplated revegetation of the adjacent mine bench outslopes as part of the bid package. Experience gained this year indicates that the conventional hydro seeding which was envisioned may not be successful at these areas. This is due to three factors: the steepness of the slopes, the length of the slopes and the high volume of runoff from thunder showers and snow melt. At this point, I would recommend that the revegetation requirement 17