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It is Holcim's intent to minimize the disturbance to those areas already reclaimed. <br /> It is anticipated that the quarry will mine approximately 70,000 to 100,000 metric tons of raw <br /> material to produce the 50K to 90K metric tons of gypsum product for the Portland Plant. <br /> Considering exploration at Titanium hill will be successful, re design of North East wall. <br /> Mining will require overburden removal and Life of Mine strip ratio is estimated at 2.3:1. <br /> It is planned that mining operations will be seasonal and occur four to six months during the <br /> year. Haulage from the quarry site to the plant site in Florence will occur five days a week <br /> throughout the year. <br /> Description of Mining Methods (see Exhibit C, maps) <br /> Mining will be conventional open pit mining utilizing drilling, blasting, loading, and hauling <br /> methods. A portable crushing and screening system will be brought on site where the <br /> gypsum will be crushed and screened for impurities. Final product will be stockpiled and <br /> then hauled by a third party service from Coaldale to the Portland Plant located <br /> approximately 5 miles east of Florence, Colorado. <br /> Development work will be performed via bulldozer, loader and trucks. The majority of <br /> development work will be to expose the gypsum beds by stripping out the approximately 12" <br /> of growing medium and stockpiling it in Topsoil Depositional Areas. <br /> Once the growing medium has been removed and the area has been leveled, the gypsum <br /> deposit will be penetrated with a rotary blast hole drill. Drill holes will be 3"to 4" in diameter <br /> and 30 feet deep. The material will be fragmented via non-electric blasting systems and <br /> blasting agents. It is estimated that there will no more than ten (10) blasts each year. The <br /> average size of blast will be approximately 32,000 metric tons. Blasting will comply with ATF <br /> regulations and will be monitored for seismic control. <br /> Mine design parameters. Per Rule 6.5, a Slope Stability Assessment(attached)was <br /> conducted with SRK (SRK Project, June 18. 2019); they used the probabilistic assessment <br /> and the Ritchie,1963 criteria. Next table and graph summarize parameters by regions. <br /> Design region Bench Height Bench Berm Probability of Failure% Spillage <br /> (ft) Slope (2) Width (ft) PL W Toppling (ft) <br /> Region 1 - Upper 30 65 20 21 35 6 18.0 <br /> Region 1 - Bottom 30 65 20 21 35 6 18.0 <br /> Region 2 30 75 20 1 27 9 12.3 <br /> Region 3 30 80 20 10 25 10 25.4 <br /> 60 75 30 10 23 10 23.7 <br /> Region 4 30 65 20 5 19 9 24.7 <br /> 60 60 30 4 15 8 24.7 <br /> Spillage. Total berm area occupied by a minor instability <br /> Source: SRK <br />