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 | 12 and compaction. Overall slopes will range from 10H:1V to 2H:1V slopes, depending on target location and reclamation requirements discussed in AM07. For purposes of estimating these costs, it is assumed one (1) drilling and blasting operation, using a Atlas Copco D65-T4F or equivalent, will be conducted to generate and load the material for transport to the Satellite South Pit. Based on current drill and blast production rates at the quarry, it is assumed that blasting will occur one to two-days per week and will generate approximately 40,000 tons (29,412 LCY). The rest of the week will be used to load and transport material (discussed in Item 2.2 below). Based on the 29,412 LCY per week production rate and 1,854.183 LCY needed for backfill, drilling and blasting will take up to 16 months to complete. Item 2.2 Mined Area Earthwork: Fill and Compaction The average haul distance to the Satellite South Pit from the drilling and blasting location is up to 0.25 miles. Material will be loaded from the blast area using one (1) front-end wheel loader (Caterpillar 992 or equivalent) and transported to the Satellite South Pit using three (3) rigid 100-ton haul trucks (Caterpillar 777 or equivalent). All fill material will be placed and compacted using one (1) CAT D9 bulldozer as follows: · Placed in loose, horizontal lifts not to exceed 30-inches thick, assuming maximum rock sizes are limited to two-thirds of the lift thickness · Compacted to achieve greater than 80% of the maximum dry density determined in accordance with ASTM D698 · Placed in a manner that allows for a moisture content within 3% of optimum based on ASTM D698 Based on an estimated backfill requirement of 1,854,182 LCY, 6 days per week of operation and 12 hour work days, it is assumed that it will take up to 16 months to complete fill and compaction activities. Item 2.3 Compaction Testing Throughout backfill and compaction activities, quality assurance and quality control testing shall be performed. Testing for in-place density and moisture content will be performed in accordance with ASTM D6938, using nuclear testing methodology, and it is assumed this testing will be done once per lift and each lift will take approximately 1 day to complete. Costs for QA/QC testing assume a unit rate for each lift for reclamation of the Satellite South Pit. For purposes of cost estimating, it is assumed up to 48 days (based on 48 anticipated lifts) will be needed to complete compaction testing. Item 3.0 Dewatering During backfill operations, groundwater and surface water will be collected in sumps constructed within the pit where water will collect and be pumped using an electric dewatering pump to Outfall 006 for discharge. As discussed in Section 2.3, a dewatering rate of 5 gallons per minute is anticipated in the Satellite South Pit. Dewatering will also be needed to address any precipitation of stormwater inflow (similar to current dewatering completed in the South Quarry as part of the mining operations). For purposes of cost estimated, it is assumed that two (2) dewatering pumps (6”