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Fifty-five samples were analyzed for Uranium, Ra 226, gross alpha, and gross beta. <br />Additionally, ten percent of the samples were analyzed for thorium (Th) 230 and lead (Pb) 210. <br />2.6 Subsurface Soil <br />To obtain a radiological profile of subsurface soils in the project areas, RG 4.14 suggests <br />subsurface soil samples be obtained at the center of operations and at 750 meters in four cardinal <br />compass directions and three samples should be obtained at each location one time, prior to <br />construction, to a depth of one meter. In addition, NRC's NUREG 1569 suggests that a general <br />description of the site soils and their properties be provided to support an evaluation of the <br />environmental effects of potential construction and operation erosion. <br />Twenty-one soil profiles were collected at the locations shown in Plates 1 and 2. To locate the <br />samples, a virtual axis was constructed through a plan view of the ore bodies, around which a <br />grid was drawn 750 m from the axis. The number of sample locations in each 750 m radius of <br />the traditional circular/polar grid was used to establish a basis of sample location density <br />(m2/sample) for each radial segment. It was then translated mathematically to an equivalent <br />sample location density for the grid around the axis. The resultant number of samples per <br />segment was then used to determine spacing of samples along the perimeters of each grid <br />segment and along the central axis. Finally, in consultation with CDPHE, sample density was <br />increased at ore body locations and decreased in area away from the orebodies. <br />Sample locations were established via a hand-held GPS unit. At each location, a profile was <br />obtained by collecting three soil samples at the following depth intervals: <br />• 0-30 cm <br />• 30-60 cm <br />• 60-100 cm or at refusal <br />The samples were shipped in glass containers within an ice chest with packing materials to guard <br />against breakage. Samples were shipped via overnight delivery with proper chain of custody to <br />ELI for analysis. The samples were analyzed for the parameters listed in Table 2.4. <br />2.7 Direct Radiation Measurements <br />RG 4.14 suggests direct radiation measurements be obtained at 150 m intervals out to 1,500 m in <br />eight cardinal compass directions from the center of the milling area, plus at air particulate <br />stations one time to determine average exposure rate. A program was designed which utilized <br />GPS-based scanning technologies capable of providing much higher measurement density and <br />more uniform gamma measurements over large areas. <br />April 2009 11 Site Characterization Plan