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(Page 2) MINE ID # OR PROSPECTING ID # M-1978-107 INSPECTION DATE 2/20/03 OBSERVATIONS This inspection was performed by the Division as part of its monitoring of Constructio operator's representative was contacted about the inspection, and a time was arranged operator's representative named on page one was present throughout the inspection. INSPECTOR'S INITIALS RCO n Materials 112c permits. The to jointly inspect the site. The The permit ID sign was observed at the entrance, and numerous permit boundary markers, consisting of 10-foot tall PVC pipe, were also seen along the W and E boundary. Activities appear to be contained within the boundaries. There are berms across the northern end of the permit to shield the county road and nearby residents from the sight and noise of the operation. The berms are permanent and are being revegetated, most successfully with rabbitbrush. The lower pit floor (northern end of the site) was active at the time of the inspection. A loader and line of haul trucks were removing stockpiled gravel from the site. This end of the permit is used only for processing and stockpiling. Side slopes are generally graded and revegetated. No further mining will occur in this pit, and the slopes will not be redisturbed. The terminus of the overland conveyor system is located here on the floor. It was inactive but functional. A small stock of spare parts for it is also located here on the floor. A small amount of stockpiled topsoil exists along the access road to the upper (southern) pit. The topsoil will eventually be used for reclaiming the roadway. The upper pit is where excavation occurs and where the beginning of the conveyor is located. There was no excavation or processing being carried out at the time of the inspection. The northwest portion of the upper pit is fully mined out, and partially reclaimed. Earlier excavation resulted in a very deep pit and tall highwalls. Due to the high percentage of reject fines in this aggregate, a significant amount of material was available for backfilling. The floor was raised by about 20 feet or more, to about the elevation of the upper end of the conveyor. The north edge of this area blends into the native hillside, and will not be mined further. It has been graded and slash has been scattered on it. Reclamation of that slope is not finished since there is still no revegetation. The south edge of the backfilled area has been temporarily sloped for stability. Future mining will commence there and continue southward. Small stockpiles of sand were noted in a couple locations in the upper and lower pits. The southern end of the area to be affected by future mining was marked by a flagged lath about 100 feet north of the south boundary fence. Adequate marking of the limits of the affected area will be important, and the operator is encouraged to do so. As the aggregate is mined out on west side of the conveyor, operations are planned to move to the east side, to mine down the low ridge. This ridge is bounded on both sides by ephemeral drainages, so adequate stormwater control and sediment containment will be important. The current upper pit drains to the west. Most of the west side of the floor area contains a runoff control berm, though the berm is missing in one location. Though much of the precipitation likely percolates in to the deep fi(I material there, it appears that some surface runoff has occurred, which has left the pit floor and entered the natural drainage on the west. This recent runoff transported sediment down the slope and possibly into the drainageway. The stormwater control must be improved at this location. At the present time. this is noted as a problem for the operator to correct. Please see the correction date on the last Dane. (It should be noted that there is another location where improvements to the stormwater control should be examined: at the location where the tribal access road enters the upper pit from the north. A low berm which contains stormwater but allows vehicular passage may be needed. This is not a problem location at this time.) The upper end of the conveyor is in good condition also. Its upper and lower footers may be easily removed, as well as the sections of conveyor, which all lie on railroad ties. Minor repair to the ground at some of the ties is needed, due to minor erosion in the ephemeral gulch which the conveyor crosses. There are no noxious weeds on the roads, the sloped areas or the backfilled area, and none observed elsewhere on the site. The permit includes a noxious weed control plan. The operator is reminded that revegetation is most successful when carried out soon after reclamation earthwork is finished, due to generally optimal soil conditions. Prompt seeding also helps to impede the strong early establishment of weeds, improving future weed control.