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Revised Reclamation Plan for Eureka Gravel Pit M-1990-070 San Juan County is submitting this plan for revisions to the current gravel mining permit on the Eureka Gravel pit. The original plan was submitted with errors on the reclamation plan and the mining plan. San Juan County would like to submit this post mining plan for the Eureka Pit. j San Juan County has ceased all mining at the current pit and will only be ~ H conducting reclamation efforts on the current affected area. ~ ~, LL o ~ San Juan County has previously provided the Division of Minerals and Geology z with a copy of a stability study of the gravel pit conducted for San Juan County by - Lambert and Associates. This proposed revision implements the all ° recommendations in the report which are economically feasible. The specific changes which San Juan County requests be made to its existing permit are as follows: 1. The County proposes to correct the proposed final slope to 1 H:3V or 1 H:4V so that the final proposed slope for the affected area is similar to the slope of surrounding areas. This change is requested because the original permit proposed a final slope of " 3 or 4:1" intending to mean three or four feet of vertical distance to every foot of horizontal distance. 2. The County proposes to amend the permit to allow the county to place all of the remaining spoils piles of materials from past screening operations back into the excavated slope toe below the scarping and sloughing areas. There is approximately 3000 to 3500 yards of materials that can be backfilled in to the toe of the excavated slope. Once placed into the excavated area, the County proposes to bulldoze the material as far up the slope as possible (perhaps as much as 50' to 60') upslope at the maximum safe angle for operation of a bulldozer. The backfill will be placed along the excavated slope from the western edge of the pit area for approximately 130' to the northeastern edge of the permit area. The ball materials will be compacted by the equipment used to place the backfill. These backfill materials are from gravel screening and will not compact very well to any real densities. There will be no placement of top soils on the reclaimed areas since none where present of removed before or during any mining operations. Once the backfill material is placed in the excavated area, the County proposes to level off a narrow bench along the top of the backfill to help catch some of the finer materials from the scarping and slough and let these materials gradually fill in upslope to try and get the slope to stabilize. In addition, leveling a bench at the top of the ball may help slow down further scarping and erosion above the slope toe and may hold some of the materials above from sliding down since the spoils materials is a little larger. The county may have to use an excavator to place some of the materials in areas on the southern edge of the affected area to help stabilize the edge of the aspen trees.