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Martin Marietta Materials <br />Spec -Agg 2014 Annual Report <br />4.0 MINING PLAN AND PROGRESS <br />Mining activities have been focused in two distinct areas: the Main Pit and the Southern Expansion Area <br />(Figure 2). Minimal mining activity appears to have occurred in the Main Pit since the last report. The <br />sump location appears to look similar overall to the 2013 investigation; however, the pump was not <br />running at the time of our March 2014 site visit. Plant operation records show the daily pumping from the <br />main pit varied from 3 hours to several hours based on weather condition. In general, 80,000 to 100,000 <br />gallons per day of water were discharged (mainly from groundwater). <br />Significant mining activity has taken place in the Southern Expansion Area since our last annual report <br />and between our November 2013 and March 2014 site visits (Photos 1 and 2). The current temporary <br />benches are being advanced to approximately the 6,720 to 6750 ft elevation (Figure 2) with reclamation <br />occurring in stages following excavation along permanent bench. Three temporary benches were actively <br />being mined during our November 2013 and March 2013 site visits, including an upper bench near the <br />western margin of the Southern Expansion Area (see stations 14 -01 and 14 -04 in Figure 2). The next <br />lower bench is being mined starting from the eastern side of this level and working to the west (see <br />stations 14 -02 and 14 -05 in Figure 2). An additional area of recent mining was observed in the <br />northwestern portion of the Southern Expansion Area (see station 14 -03 and 14 -06 in Figure 2). This <br />area may represent the start of a new bench level for the next lower bench of the Southern Expansion <br />Area. <br />Based on the current mine plan developed by Martin Marietta (formerly Lafarge West, Inc.) in December, <br />2003 and the current Colorado Division of Minerals and Geology mine plan, we understand that the mine <br />will eventually be excavated to the topographic configuration shown in Figure 2, with an approximate final <br />mine floor elevation of approximately EL 6,200 ft. The orientation of the planned final mine high walls is <br />the basis for our rock slope stability assessment, as discussed in Section 6.0. <br />March 31, 2014 Page 5 Lachel & Associates, Inc. <br />Project 13364013 00 ®2014 All Rights Reserved <br />