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models run by the NOAA project that Colorado will warm by 2.5 °F by 2025 and 4 °F by 2050, relative <br />to the 1950 -1999 baseline (Ray et al, 2008). On the other hand, no consistent long -term trends in <br />Colorado for precipitation are present. Changes in Colorado's water cycle are projected to be the <br />source of many impacts of climate change. For example, in Colorado, between 1978 and 2004, the <br />spring streamflow pulse has shifted earlier by about two weeks with strongest shifts occurring in <br />western and southern Colorado (Clow 2007). Shifts in timing of spring runoff due to rising late - winter <br />and early spring temperatures may be augmented by changes in water flows. <br />Environmental Effects <br />Under the proposed action and all action alternatives there will be a minimal net contribution of <br />GHG emissions from BLM lands as a direct impact of fossil fuel combustion from a stationary diesel <br />engine at mine operations. <br />GEOLOGIC AND MINERAL RESOURCES <br />Affected Environment: <br />A major authority on gold placers in Colorado was,prepared by Dr. Ben H. Parker, Jr. and is <br />documented in the October 1974 Colorado School of Mines Quarterly. Much of the information <br />provided below originates from this publication. <br />The area in which the project is being proposed consists of glacial outwash from the Pleistocene, most <br />likely pre -Bull Lake in age. This material is classified as the Fairplay Placer, which directly overlies <br />the proposed mining site. The Fairplay placer is located immediately northwest of the town of Fairplay <br />and extends downstream about four miles, as shown in Figure 8. The area is about 1,500 acres in size, <br />or a little more than two square miles. <br />Gold in these placers was derived from all the centers of mineralization in the South Platte watershed <br />above Fairplay. These placers are alluvial deposits derived from glacial debris and include both <br />meltwater channel and outwash plain deposits formed during Bull Lake and Pinedale times and <br />modern stream deposits formed by post - Fairplay reworking of outwash gravels. The gold basically <br />came to be here through a series of weathering and transport and deposition by advancing of glaciers, <br />meltwater distribution and alluvial processes. These processes were centered along the course of the <br />South Platte River, which maintains a similar course today. It is concentrated in the lateral and terminal <br />moraines, as well as the outwash plain below Fairplay. <br />The upper part of this placer was discovered in 1859. Small scale work continued into 1869, when it <br />was reported that each man was taking out $5 to $10 per day. Dredging work continued in the upper <br />part of this placer on and off through 1994. <br />Considerable historic placer mining has occurred in the Fairplay mining district. Figure 8 shows some <br />of the un- reclaimed historic mining disturbances in the vicinity of this project. The Fairplay placer has <br />also been extensively tested in the outwash plain below the moraine, which covers the subject area. <br />This testing was documented in an older report prepared by Parker in 1961 and was used as the basis <br />for developing the maps shown in the Parker report. The gold concentration map was scanned, geo- <br />referenced and is shown in Figure 9. <br />20 <br />