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• (Page 2) • MINfi ID # OR PROS PfiCTING ID # M-97-084 INSPECTION DATS~/15/97 INSPECTOR'S INITIALS RCO OBSERVATIONS This was a pre-operation inspection performed by the Division, for this 110 Construction Materials permit application. The applicant was contacted about the inspection, but was unable to be present for it. The consultant who prepared the application represented the operator, and was present throughout the inspection. The "Notice" of permit application, required to be posted onsite during the time of permit application review, was observed to be present and visible from the highway. The southwest and southeast permit corner markers were observed. The west side of the permit abuts the right-of-way of Highway 550. The east edge o£ the permit is defined by the boundary of the Ouray city limit, and is in the approximate vicinity of the lowest cliff face. The north edge of the permit is also defined by the boundary of the Ouray city limit. This side is near the city's Rotary Park. The south edge of the permit is marked by an old barbed wire fence, and a pasture on the adjoining property. The site will be accessed on the west side, directly from the highway; there will be no access £rom the south or the north. The material to be removed during the mining of this site is unconsolidated alluvium and waste rock, presently lying in a steeply sloped fan at the base of a narrow gorge in the cliff face. Once the fan is removed the site will be nearly level, or will~~at most require minimal grading to be level. The fan and the mouth of the gorge are on the south half of the site. There are several isolated low areas on the remainder of the site, but impoundment of water does not seem to be significant here, due presumably to the permeability of the floor. Even so, the planned development of the site should consider drainage control. There is a series of cliff faces extending up the mountain above the permit area to the east. The narrow gorge is a £eature which cuts through all o£ them (as viewed from the west side of the valley floor). The gorge itself seems to be present because the rock there is more fractured or erodible, being a mineralized intrusive geologic feature. This is evidenced by the series of historic gold mine portals and surface structures still present along the gorge, above the permit area. The material in the fan appears to have been deposited in distinct layers and due to different factors. The surface is deeply incised by historically recent runoff in a single gully which is aligned somewhat with the fall line of the gorge. It seems to nearly disappear by the toe of the fan, the force or volume of flow apparently reduced by that point. The surface material consists of what appears to be new and old talus, plus some yellow-ocher mineralized material (limonite, according to the file). The topmost layer along the gully and toward the northern portion is where most of this mineralized material was seen. It is of an angular nature, ranging in size from fine-grained up to five inches, and contains a small amount of pyrite. It was agreed during onsite discussion with the operator's representative that it is most likely waste material that was disposed of from the upslope gold mines, during their active operation. (Additionally, there are numerous small items of historic mining-related debris scattered on the alluvial fan.) There do not appear to be piles of waste rock at the portals presently, which would contribute to significant amounts of mineralized rock falling into the permit area. Overall, the amount of this mine- related waste rock on the total fan material to be removed appears to be small. However, there are several steep benches of unconsolidated talus separating the individual cliffs in the series, which may contribute to the future material falling into the area, regardless of any conjunction with a precipitation event. There were, in addition to the smaller-sized pieces of rock described above, many large rocks lodged in the gorge or perched upon a shelf, ranging up to 10 to 20 feet in size. These often were supporting more material, and the .u.