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Section 6.2.1, Proposed Cover Design for the Sunday Mine Low-Grade Stockpile: <br /> Figure 6-1 shows the approximate location where average surficial uranium <br /> concentrations above 500 ppm were identified at the Sunday Low-Grade Stockpile. As <br /> discussed below, this area will be resurveyed using XRF analyses to provide a clear on- <br /> the-ground delineation of the area to be covered with development rock. Figure 6-2 <br /> shows the location of the development rock that will be excavated for use in the cover <br /> material and the proposed transportation route to the low-grade stockpile. A random <br /> XRF survey of this development rock found that uranium concentrations were <br /> substantially less than 500 ppm. PRM's plan for placing the rock cover is as follows. <br /> 1. Provide both the DRMS and the Bureau of Land Management (BLM) with verbal <br /> notification of the construction schedule prior to the start of construction. <br /> 2. Construct a temporary access road to the top of the low-grade stockpile at the <br /> southwest corner of the stockpile. <br /> 3. Grade down safety berms and fill in drainage ditches located on the north end of the <br /> top of the stockpile to allow for truck access to the area and the uniform placement <br /> of the cover material. The drainage ditches should be filled in with development rock <br /> containing less than 500 ppm uranium. <br /> 4. Establish a 40-foot by 40-foot grid pattern in the north end of the stockpile where <br /> elevated uranium concentrations were recorded. This grid pattern should include the <br /> area defined in Figure 6-1 and the immediate surrounding areas. Each grid is to be <br /> assigned an alpha-numeric ID to simplify field reporting during cover placement. <br /> Wooden stakes, pin flags and/or spray paint can be used to identify the grid points. <br /> 5. Survey each grid with the XRF instrument, taking 5 random measurements in each <br /> and averaging the results to determine if the grid is below or above the 500-ppm <br /> uranium concentration. If there a wide variance in ppm values within a grid, the grid <br /> may be divided into four 20-foot by 20-foot sub-grids with 5 additional random points <br /> measured and averaged in each sub-grid to obtain a more accurate uranium <br /> concentration for these areas. Each random measurement is to be recorded in a <br /> notebook along with the grid or sub-grid ID. <br /> 6. Install wooden stakes offset from the identified perimeter of the 500-ppm-and-above <br /> readings. Offset stakes should be about 15 to 20 feet from the edge of the cover <br /> perimeter and spray painted or flagged for ease of identification with the off-set <br /> distance marked on the stake. <br /> 7. Prepare a sketch of the area to be covered using the base map from Figure 6-1 and <br /> a tape measure. This sketch can be given to the equipment operators and also be <br /> used later in compliance reporting with the DRMS and BLM. <br /> 8. Install wooden 2-inch by 2-inch stakes within the cover area at a height of 12 inches. <br /> These stakes are to be spray painted a bright color and used as visual aids for the <br /> equipment operators to facilitate placement of a minimum of 12 inches of loose <br /> cover material. <br /> 9. Excavate and transport development rock from the development rock stockpile to <br /> the top of the low-grade stockpile where it will be graded to form a 12 to 18-inch <br /> 9 <br />