2024-02-01_REVISION - M1973021 (2)

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Ninth Technical Revision (TR09) to Permit M-1973-021, Holcim- WCR, Inc. Morrison Quarry January 2024 | 10 3 Exhibit E – Reclamation Plan 3.1 Rationale for Technical Revision Reclamation for the South Quarry and West Quarry above El. 6,600 remains unchanged from AM07. This section focuses on reclamation of the Satellite South Pit introduced in Exhibit D – Mining Plan. Holcim will be evaluating the possibility of leaving a portion of the pit areas currently slated for backfilling available for water storage during mining operations, but the reclamation and backfill called for herein and in AM07 will remain the reclamation plan unless modified and approved by DRMS. Exhibit F-1 shows reclamation within the South Quarry that is currently underway along the western slope, referred to as the South Quarry West Wall above El. 7,000. 3.2 Satellite South Pit Reclamation Overview Satellite South Pit reclamation will include backfilling the pit to El. 6,600 with materials generated on- site. Based on an initial 40H:40V bench configuration, the volume of the pit requiring backfill is approximately 2,648,832 yd3. With an assumed material swell factor of 70%, the volume of material needed to backfill the Satellite South Pit is 1,85,182 loose cubic yards (LCY). As was discussed in Exhibit D – Mining Plan, Section 2.3, mining will occur on two "fronts" simultaneously: one continues South Quarry development, and one develops the West Quarry. In early 2027, the timeframe when the Satellite South Pit is anticipated to reach its final base elevation (estimated at El. 6480), the West Quarry mine plan will have advanced to the El. 6944 bench. The current reserve analysis for the South Pit from El. 6944 to El. 6600, in the area below the West Quarry, is 11 million tons of mineable gneiss (~8.1 million LCY) and 2.5 million tons (~1.8 million LCY) of waste material. The remaining reserves in this area will provide adequate material for the Satellite South Pit backfill. If additional mining is not anticipated or approved in a permit modification, reclamation work will commence. Holcim intends to continue mining the South Quarry (below the West Quarry El. 6944 bench) in accordance with the approved mining plan and use material from this area to backfill the Satellite South Pit. As needed throughout backfill operations, stormwater will be managed in accordance with the Storm Water Management Plan (Rev. 6, June 2021). Once backfill has been completed to El. 6,600, final grading, restoration, and revegetation will be completed in accordance with the AM07 reclamation plan with one exception. The final grading of the South Quarry floor (El. 6,600) will be completed with a 3% slope (southwest or northeast) conveying stormwater to Outfall 003 and the main quarry access road which will remain per AM07. This final grading strategy combined with elevating the South Quarry floor to El. 6,600 removes the horizontal drain requirement recommended in AM07. Refer to Exhibit F for the reclamation map and three cross sections summarizing the key attributes of the modified South Quarry reclamation plan.