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SAMPLE LOCATIONS AT WHIRLWIND MINE <br /> FOR BASELINE, MWMP, &SPLP ANALYSES <br /> The uranium-vanadium deposit to be produced from the Whirlwind Mine is hosted in the <br /> fluvial sandstones of the Salt Wash Member of the Morrison Formation. Almost all the <br /> ore in this mine, as well as the other older mines in the Beaver Mesa/John Brown district <br /> occurs in the upper sandstone sequence of the Salt Wash, referred to as the Top Rim. <br /> Smaller deposits occur in a lower sandstone, referred to as Middle Rim, separated from <br /> the Top Rim by some 30-70 feet of mudstone. The physical characteristics and mineral <br /> composition of the Top and Middle Rims are essentially the same. <br /> Sandstone sequences are composed of several individual sandstone beds deposited by <br /> meandering streams flowing across a large flood plain. Therefore, each sequence <br /> consists of numerous sandstone lenses (1-15 feet thick) interbedded with thin mudstone <br /> beds. Locally, the sandstone beds will be in contact with other sandstones yielding thick <br /> sandstone units of several tens of feet. Usually, though the Top Rim has a few lenticular <br /> mudstone beds of a few inches to several feet thick. <br /> Habit of the uranium-vanadium mineralization is variable. Commonly there is thin (4 <br /> inches to 2 feet) ore near the top or bottom, or both, of individual sandstone beds which <br /> may extend laterally to over a few hundred feet. Often there will be areas where the ore <br /> will "roll" from an upper layer through the center of the sandstone to join the lower layer, <br /> making ore several feet thick. The ore also tends to follow cross bedding in sandstones. <br /> The common method used to mine these thin, erratic deposits is random room-and-pillar. <br /> A technique called split-shooting is employed wherein ore and intervening waste rock are <br /> blasted separately to reduce dilution. <br /> Sample locations for the baseline, MWMP, and SPLP analyses were chosen to represent <br /> the varying materials to be encountered during production. Samples WW-01, WW-02, <br /> and WW-03 are samples of ore which represent a"roll" configuration, a sandstone <br /> bottom layer, and a sandstone top layer as would be expected in a normal split-shooting <br /> situation, respectively. The other three samples represent waste rock that will be <br /> removed in accessing the ore. Descriptions of the six samples follow: <br /> WW-01 Ore: Map Coordinates 108,790E 17,950N (north rib of drift). Composite sample <br /> over 5.5 ft interval, where ore is rolling from upper part of the sandstone to the lower <br /> part. Sample includes intervening waste rock that would result in dilution during mining. <br /> WW-02 Ore: Map Coordinates 108,810E 17,890N (south rib of stope). Sample of lower <br /> ore streak, only. Ore is 1.1 feet thick. Sample is two feet thick (minimum mining <br /> thickness) to include dilution during mining. <br />