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sulfide gas will be collected with a hood and fan. The hydro- gen sulfide and entrained air will then be bubbled through a " sparger in the first tank, mixing in this tank and reusing the hydrogen sulfide which redissolves. The sludge which will come out of the bottom of the settling tank will be pumped into a filter press which will squeeze out the excess water to produce a 308 to 408 solid sludge, which can be sent to a processing mill to reclaim the metals it will contain, The squeezed out water will go back to the first compartment of the settling tank. This system has been designed with a 30 gallons per minute flow restricting valve at the front so flow surges will be eliminated. The system will be able to handle up to 500 ppm metal concentration and safely treat any sudden increase in the metal contaminant concentration of the incoming water. The water which will be discharged to the environment in Cash Gulch will have the following characteristics: Element Found Total suspended solids Copper Zinc Lead Mercury pH Water Discharged from Treatment Plant <10,0000 <0,0100 <0.0100 <0.0100 <0,0001 6.9 A comparison of the analyses of the mine water and the receiv- ing water shows that the treated waters and, in some cases, the raw mine waters are better than the receiving waters. Vegetation No rare, threatened, or endangered plant species have been identified in the Gold Hill area or on the proposed mine site. The existing vegetation has been classified as a coniferous forest consisting of mixed cone-bearing trees of the Pine fam- ily including pines (Pinus), spruces (Picea), and Douglas-fir (PSeudotsuga). These trees are resinous evergreens, with a straight axis and a narrow crown and are characteristic of acidic soils, often sprouting after fire. The coniferous for- est is widespread and extensive throughout the general area, and can be found at altitudes between 6,000 feet and 10,000 feet. It encompasses the lower and upper montane zones which includes Lodgepole and Ponderosa pine, Engelmann and Blue spruce, Douglas-fir, and thickets of broad-leaved trees and shrubs along streambanks. These zones are often referred to as the transitional zone between the foothill and subalpine zones. These zones overlap and telescope into each other, and one zone may be present on a south slope while another will be found across the valley on the north slope at the same alti- tude. Plants which are characteristically found in one zone, can sometimes be found in favorable areas in the neighboring zone above or below their usual habitat. Douglas-fir, Lodgepole pine, and Engelmann spruce are found at higher elevations and Ponderosa pine at lower elevations scat- tered in stands of pure and mixed trees. Douglas-fir is con- sidered the climax, or original, forest type in this area be- fore the boom days of mining in the 1800's, when these trees were cut or destroyed by forest fires. The present stands of Ponderosa and Lodgpole pine and Engelmann spruce came in after 1900, L.imbex~ pine and Blue spruce are also present as isolated trees and in small stands, Rocky Mountain juniper and Quaking aspen can be found in the area between the Hazel A mine portal and tt~e Cash and Who Do mine portals, Quaking aspen, Narrowleaf -9-