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hydrogeologic conditions are suitable. Ground water occurs in both bedrock and alluvial deposits in the vicinity of the proposed mining operation. The potential for groundwater within the area of the mine is greatly limited by the extreme dip of the rock strata which results in prohibitive drilling depths within a short distance. Al] water from the three sandstone zones is of asodium-bicarbonate water type. Total dissolved solids range from 575 to 1,340 mgl1. This water type and range of concentrations are very similar to analyses from the same geologic units taken from other locations along this structure and stratigraphy sequence. Climatoloey The climate is semi-arid with an annual precipitation of 16 inches. Average monthly precipitation vazies little throughout the year. Precipitation varies little seasonally, averaging one to two inches per month. Snowfall can reach up to 60 inches in higher elevations. Summers are hot, marked by very low humidity and cool nights. Winters are cold, generally snow- free, but with frequent blizzard conditions. The mine site has a typical alpine climate, experiencing long, cold winters, averaging from low teens at night to 30 degrees Fahrenheit in the day, and moderate summers. "Mountain top" air flow of cold night air drains from the mountain sides down to the Colorado River Valley. Prevailing winds blow from west and northwest to the southeast with an average velocity of 5.3 mph. Soils Soils in the area are characterized as moderately deep to deep, well-drained loamy with a dark colored surface layer. Variability in the characteristics of the soil in the area is primarily due to slope and topography. Deeper soils are located in the valley bottoms and at the foot of slopes while the shallower soils occupy the steeper side slopes. Two soil types have been identified at the mine site. These are the Heldt silty clay, found on the lower slopes, and the Nihi] stony loam found on the steeper slopes. The Heldt silty clay occurs on alluvial fans and side slopes of the mountain valleys. The clay is fine, slightly montmorillic and is grayish-brown in color. It varies from 10 to 60 inches in depth and is well drained. The Nihil stony loam (a loamy-skeletal mixture of sand and clay) occurs in alluvial fans and side slopes of the mountain valleys. It is very pale brown in color. It is a deep (60 inches), well drained soil with rapid permeability and low water retention capability. Vegetation Vegetation baseline information is contained on PAP pages 3-124 through 3-142 of Volume I, Appendices 3.6-1 in Volume II, and 3.6-2 and 3.6-3 in Volume VI. The revegetation plan is contained on pages 4-68 and 69, and 4-71 through 74 in Volume I. July 25, 2001