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_~ :~ .~ applied for in the following sequence after the approval of this application. Date of Application or Notification Boulder County Land Use Department land use permit concurrently Engineering Department road construction plans 6 months Building Department accessory building plans 6 months Health Department environmental health concurrently State of Colorado Colorado Division of Mines operator's notice of activity 1 month application to store, transport and 4 months use explosives Colorado Division of Wildlife wildlife statement concurrently Colorado Department of Health NPDES permit concurrently United States of America Mine Safety and Health Administration operator's notice of activity 1 month application to store, transport 4 months and use explosives Occupational Safety and Health Administration operator's notice of activity 1 month Geologic Summary The Boulder County, Colorado telluride belt is located at the northeastern end of the Front Range mineral belt and contains the Gold Hill, Central, Jamestown, Magnolia and Sugarloaf min- ing districts (see Map D1. The telluride belt is part of a broad, north-trending area of mineralization encompassing about 50 square miles. The predominant country rocks are Pre- cambrian granites, gneisses and schists which are bounded on the east by Paleozoic and Mesozoic sediments which form the foothills west of Boulder. The Precambrian rocks have been intruded by Early Tertiary stocks and dikes that range in com- position from diorite to sodic granite. The telluride ores apparently have a close genetic relationship to small, incon- spicuous dikes and intrusive breccias of biotite latite which • are both temporally and spatially related to the ores. The telluride belt is cut by a strong system of northwest- trending faults, locally called breccia reefs or dikes, which exerted a significant influence on the distribution of ore mineralization. Threc of these northwest-trending breccia reefs, the Maxwell, Hoosier and Livingston, are nearly paral- lel, spaced about 1~, to 2~ miles apart, and can be traced for 15 to 20 miles. Two other breccia reefs, the Poorman and fiortune, have a more westerly trend and cut across the Maxwell to the Hoosier. The veins of the telluride belt fill fault fissures that are nearly all younger than the chief movement and mineralization along the breccia reefs. Most of the productive veins strike northeast at almost right angles to the reefs and dip steeply to the northwest. They can be traced on the surface for more than half a mile, and are from 1 to 5 feet wide. While the gold-silver telluride veins have accounted for most of the production from the Boulder County telluride belt, lead-silver ~, veins and pyritic gold veins have contributed appreciable amounts of ore as well. -20-