2016-09-09_PERMIT FILE - M2016026

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EXHIBIT L WORST CASE RECLAMATION SCENARIO The worst case reclamation scenario at the 5 Mile Pit will be when the greatest backfill is required and the greatest dewatering is necessary to install said backfill. This will be at some point during the mining of Phase 1. The backfill quantity is limited by a combination of the county permit(no more than 1000 feet of unbackfilled mining slope) and the maximum depth of the final lake. This can be found in Phase 1. The lake area at this point will be 7.3 acres. Option 1 -Exposing Groundwater 1. Dewatering 7.3 acre lake that is 12 feet deep on average. 87.6 ac-ft @$75/ac-ft= $6,570 2. Backfill to the lake level to close off exposed groundwater. 87.6 ac-ft= 141,328 CY. 141,328 CY @ $1.50/CY to haul and place= $211,992 3. Backfilling 1000 feet of 1.5H:1 V mining slope to 3H:1 V for a highwall height of 10 feet. 2,700 CY at$1.50/CY to haul and place= $4,050 4. Backfill and grade detention pond. 6,200 CY @ $1.50/CY to haul and place=$9,300 5. Rip road areas in preparation for topsoiling.4 acres @ $250/ac. =$1,000 6. Replace topsoil on all disturbed areas. Assuming all areas disturbed except for Phases 2 and 3. 25.6 acres to a depth of 12 inches. 41,301 CY @ $1.50 CY to haul and place=$61,952 7. Remove all facilities and equipment. $5,000 8. Seeding and mulching all areas above water line. 25.6 acres @$700/acre= $17,920 Based on these costs, and a 28%DRMS cost factor,the total bond for the 5 Mile Pit should be $424,620. Option 2-Exposing Groundwater 1. Dewatering 7.3 acre lake that is 12 feet deep on average. 87.6 ac-ft @ $75/ac-ft=$6,570 2. Backfilling 1000 feet of 1.5H:1 V mining slope to 3H:1 V for a highwall height of 2 feet. 2,700 CY at $1.50/CY to haul and place= $4,050 3. Backfill and grade detention pond. 6,200 CY @ $1.50/CY to haul and place= $9,300 4. Rip road areas in preparation for topsoiling. 4 acres @ $250/ac. = $1,000 5 Mile Pit March 2016 L-1