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Permit Number ~~ ~ j , ~ ~//~ Class and SectioniExhibit : ~__~~~~^ ' Class ^ Revision •-- -~-•---•-•---•---•-•-----•---•-•-•-•---. ~ TYPeJSeq ~ Class: O Report O Hydro OGeneral- - - - - - - -"- - - - - - - - --- -~ Doc T ype: Environmental Pry long before Earth Day awakened a new public sentiment. Company ex- perience with government and especially with the public indicate that the decision was a wise one. 300 Million tan deposit The orebody for which the Hender- son complex was developed is lo- cated about 3000 ft beneath the sur- face of Red Mountain. The deposit is approximately 3000 ft long, 2200 ft wide and from 400 to 800 feet thick. It is believed to contain 300 million tons of ore assaying 0.49% MoS~, about equal to the remaining de- posit in the Climax Mine. An impor- tantdifference is that the Climax ore yields only 0.3% MoS.. The Hender- son deposit will thus nearly double AMAX's production, with 50 million pounds of molybdenum per year coming from Henderson and 60 mil- lion from the older Climax Mine. The new deposit will increase the AMAX share of free world production of molybdenum from the present 35 to orebody occurs as molybdenite (MoS..) deposited with quartz, and to a lesser extent with quartz-fluorite, in fine and closely-spaced veinlets. The ore averages 0.49% MoS,, but high-grade samples assay over 0.8 per cent. The physical characteris- tics of the ore, as indicated by its response to core drilling, led to the selection of caving as a mining method. Further, this method will produce the quantities of ore (even- tually 30,000 tons per day) required for high production levels at the mill. Three shafts have been sunk to the orebody, the largest of which- at 28 ft diameter-is the largest mine shaft in North America. Depths are between 2440 and 3103 ft, and all shafts are lined with a minimum of 12 in of concrete. Ore is eventually collected at the rail haulage level, about 600 ft below the production level, where it is loaded onto ore trains for the 15- mile journey to the mill. nel under the Great Divide As mentioned above, the decision to locate the mill at a considerable dis- tance from the mine was based en- tirely on environmental consider- ations. The main problems in this regard were associated with tailing disposal and the avoidance of local stream pollution. These would have proven difficult if not insurmounta- ble had a mill site at the mine mouth been selected. A topographically suitable site was, however, located approximately 14 miles west of the minesite. To connect this site with the mine required the construction of a 9.6 mile long railroad tunnel and an additional 4.8 mile surface rail line. The tunnel is approximately 15 ft high by 16 ft wide, large enough to accomodate a double track, 42 in railway system. The tunnel was dri- ven from both the mine's haulage level and the exit point to the west. At holing-through, on July 15, 1975, misalignment was only five inches Semi-autogenous mills at Henderson Application (Coal only) ^ Bond ^ Enforcement ^ Inspection i ~~~~~~ ~~~~~ ~~~~~ iiui i~~~~ i~~~ ~~~~ ^1F7a