ABLA/MEFE) on moist sites the habitat type is TSME/MEFE. 

 This habitat type is known to occur on the South Fork of 

 Ross Creek-South Branch of Dry Creek ridge and on the north- 

 east slopes of Mount Vernon. On drier sites where TSME is 

 successfully reproducing the habitat type is TSME/XETE and 

 where TSME is not present it is ABLA/XETE. The TSME/XETE 

 habitat type was found only on the northeast slope of Mount 

 Vernon. The ABLA/LUHI and TSME/LUHI habitat types are clas- 

 sified as upper subalpine habitat types. The ABLA/LUHI 

 habitat type is widely distributed on most ridges within the 

 study area above 1,700 m (5,600 feet). The TSME/LUHI habi- 

 tat type occurs adjacent to but in the same areas as the 

 TSME/MEFE habitat type. Although timberline habitat types 

 do occur in the Cabinet Mountains, they were not common on 

 the study area, and no observations of wildlife were noted 

 in these types. The Larix lyallii-Abies lasiooarpa (LALY-ABLA, 

 alpine larch-subalpine fir) habitat type occurred in the 

 few sites where granitic boulders formed the walls of cirque 

 basins or peak siimmits. 



D escription of Mine Project 



ASARCO plans to extract 4 8 million tons of copper and 

 silver ore over a 16-year period from the Mount Vernon mine, 

 making it the second largest silver mine in North America. 

 During the life of the mine, a total of 2,930,000 tons of 

 tailing and 60,000 tons of copper-silver concentrate will be 

 produced annually. Copper occurs at concentrations of 0.74 

 percent, while silver occurs at 1.54 ounces per ton of ore. 



A 3-year construction phase will preface the 16-year 

 production phase. Adits will be driven into the north side 

 of the mountain at the head of Stanley Creek to provide 

 access to the ore body which is located at the 1,340 m 

 (4,400 feet) elevation (Figure 4). The ore will be extracted 

 utilizing an underground room and pillar method whereby 

 76 percent of the ore can be removed. Ore will be fed to a 

 primary crushing mill where it will be reduced to less than 

 2 cm (0.75 inch) size, then moved via conveyor belt to the 

 secondary crushing mill located at the 1,040 ra (3,400 feet) 

 elevation on Mount Vernon. At that point it will be further 

 reduced to the consistency of fine granulated sugar and sub- 

 jected to a "froth floatation" process wherein the copper 

 and silver are mechanically and chemically separated from 

 the tailing. The mineral concentrate will be dried and then 

 transported by truck to Troy where it will be shipped via 

 railroad to a smelter in Tacoma, Washington. The tailing 

 will be moved to a tailing thickener where excess liquid is 

 removed. The thickened tailing will then be transported for 

 10.5 km (6.5 miles) in a slurry pipeline to the Lake Creek 

 Valley (700m or 2,300 ft below) where it will be distributed in 



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