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(Page 3) MINE ID # OR PROSPECTING ID # M-77-300 INSPECTION DATE 9/22/99 INSPECTOR'S INITIALS ACS per day. There was no ore shipment during mine shutdown from 1989 to 1996. Road maintenance is conducted as needed. During this inspection a front-end loader was observed grading the road and a water truck was spraying the road. Ln some locations, the road is immediately adjacent Co the creek where sloughing of road fill could occur during grading operations. However, no evidence of any sloughing into the creek was observed. • The Ralston Creek canyon is widens considerably north of the guard shack and through the mine reach. Larger streambed material was observed where the canyon pinches in below the mine. Essentially, the mine reach is in a wider and lower gradient alluvial valley than is present i.n the canyon above and below the mine. • Numerous relatively deep pools were observed in the stream through the mine reack~. A semi-periodic step-pool configuration was observed. • There is a stream ford to an abandoned adit across from the former ore sorter location. Once the old adit is properly sealed and reclaimed, the stream banks at the ford location will require revegetation. • At the parking lot location the stream is channelized between bedrock control on the left bank and parking lot fill on [he right bank. The parking lot fill forms a steep bank with very little vegetation established. • A three culvert concrete bridge has been installed just above the water treatme:.~t plan[ location. This bridge is used to access a bone yard, helipad, and sludge evaporaticn trenches. The evaporation trenches are no longer a component of the sludge management system and have not been used for a number of years. Once the disturbances on the left bank are reclaimed, the bridge must be removed, as it serves no purpose under the approved post mining land use. A cost factor for removal of the bridge was not included in the 1996 Yeclamation cost estimate and bond adjustment for the Schwartzwalder Mine reclamation permit. A cost for bridge removal musC be included in the next bond adjustment. • Gabions have been installed on the right bank of Ralston Creek adjacent to the water treatment plant to prevent bank cutting during a 100-year flood. Flood protection for the wa tear treatmenC plant provided by the gabions is a requirement of the Radioactive Materials License. It is the Division's understanding that the gabions will remain in place after water treatment plant. removal and site reclamation. • The stream bank immediately to the south of the east waste dump was inspected. In 1963, a waste pile stability analysis that was a component of permit amendment AM-O1 demonstra=ed that the south end of the east dump may be unstable and had to be removed. The area under the .: emoved section of the dump has been revegetaCed and is showing a good cover of herbaceous species. • The reach of Ralston Creek immediately down gradient of the waste dumps (from approximately station 32+00 to 36+00 on the TR-04 survey) shows very dense riparian vegetation of wil Lows. • The streambed above the dumps includes channel bars and finer grained bed materi.a is than observed in other locations. The riparian vegetation is mature and includes large trees. Based on the data and description provided in technical revision TR-04, and on the observations of the streambed and bank condition made during this inspection, the Division approves the proposal in TR-04 to eliminate the eleven in stream riprap check dam structures from the reclamation pl.sn. The following two reclamation measures related to the improvement of the Ralston Creek corridor wer~=_ discussed during the inspection, and agreement was reached that these measures would be incorporated :.nto the technical revision prior to approval: 1. The section of the stream bank composed Of parking loC fill must be pulled back to form a 2:1 slope and revegetated. This project should be completed when there is minimal flow in the creek or measures implemented to prevent sedimentation to the creek. Application of topsoil and mulch ~~r erosion control fabric will aid in the establishment of vegetation. Alternating layers of compacted soil and live cut willow stems would also be useful to revegetate the regraded bank. There was discussion during the inspection that a general reclamation standard in the permit is grading of slopes to 2:1 and that specifically addressing the parking lot fill in the technical revision may be unnecessary. However, review of the permit yields the following statements: r The employee parking lot along with the rest of the area will be regraded to a flat contour, which conforms to the surrounding terrain, seeded and fertilized. i The employee parking lot area is presently a flat surface area. Once covered with approximately