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• (Page 2) • MINE ID rt OR PROSPECTING ID # M- INSPECTION DATE /Ol INSPECTOR'S INITIALS RCO OBSERVATIONS This partial inspection was performed by the Division as part of its monitoring of Hard Rock and Metals 11012) permits and to assess the earthwork associated with waste rock stabilization recently performed under technical revision TR-01. The operator was contacted to arrange a time for the inspection. The operator and representative named on page one were present throughout the inspection. The site had about 3 inches of new snow, and was not active at the time of the inspection. The required permit ID sign was observed posted at the locked gate at the entrance to the site. Most of the permit boundary corner markers, consisting of green T-posts, were observed in their proper locations. All activities appeared to be within the permit boundary. The old shed on the site was still present and secured against unauthorized entry. The portal shed appeared to be in good condition, and the portal was secured with a locked grate. Tracks lead out of the portal past the shed to a small pit recently excavated to receive waste rock. There was no debris or equipment anywhere on the pad. No noxious weeds were observed anywhere. The waste rock pile has been reconfigured, and now fairly closely conforms to the new topography depicted on the TR-01 map, received on 11 /2/2000. This earthwork is not final reclamation, since the dump contains material which is approved for removal to an offsite processing facility; the earthwork is considered to be interim slope stabilization. An excavator was utilized to pull material off the steep, north face of the dump, resulting in a gentler dump slope gradient and more distance between the toe of the dump and Dexter Creek. There is native rock riprap along the dump slope toe. The overall slope gradient appears to be approximately 3:1 throughout. Newly exposed dump rock did not exhibit the staining which would have indicated mineralization. The surface of the dump slope is rough, not having been bladed by dozer, though it is expected that some roughness will mellow over time. This roughness does not appear as if it will adversely affect stability, but may enhance the ease of establishing permanent vegetation during future reclamation, by way of providing "mini-catchments" for precipitation, seed, or organic matter from the surrounding forest. Encroachment of native herbaceous and woody vegetation (mainly narrowleaf cottonwood, Douglas-fir, and white fir) from surrounding areas has occurred, in addition to transplanting the operator has done. The post-mining land uses include recreation, and the operator stated that grass and wildflower seed would be applied next seaon. The earthwork appears adequate at this time, but monitoring during over the next few years will be needed to assess the stability and success of this project. The earthwork performed also included the clean-out of the portal discharge ditch, which is aligned on the western edge of the permit area, near the interface of dump material and the native slope materials. The water appeared clear, and was flowing through the 2-foot wide ditch about 4 inches deep. Exposed on the floor of the ditch channel was the top of an old metal pipe (12-inch diamater7) which appeared to be non-functional. The operator stated that the discharge has existed at this old (1880's) mine for many years, that the old pipe has been present for many years, but that the water did not enter the creek as surface flow. The ditch has existed for numerous years also, but was only recently cleaned out. It is unknown at this time if that has changed whether this portal discharge water still goes subsurface before reaching Dexter Creek, within the permitted area boundary. The 1980 permit map does not depict any portal discharge conveyance. and Exhibit D from the 1980 application states that "no water has been encountered at this time." The permit file does not include reference to existence of the discharge, approval or permit for this discharge, nor analvsis of the water. This lack of documentation is noted as a problem on page one of this report under the topic of "records." If the water percolates into the ground prior to leaving the permit area, then it is not considered by the Colorado Dept of Public Health and Environment ICDPHEI to be a discharge and no permit is needed. However, as groundwater, DMG must be assured that groundwater guality is maintained. The correction of the problem may take one of several directions First the operator must determine if the water leaves the permit area as surface flow or as groundwater If it is surface water then the operator must provide evidence of the existence of a discharge permit from CDPHE or their express waiver of the need for such a permit An analvsis of the discharge water must be provided also. If the discharge becomes groundwater within the permit area which presumes that it enters Dexter Creek but not at a point source then a comparison of water guality both upstream and downstream of the mine must be documented. It is probably oast the season during which the site can be accessed or water is easily sampled so the corrective action date will be postponed until 2002 Please see the last page for the correction date