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Ground Surface Radiometric Survey <br />On April 26 & 27, 2010, Nuvemco conducted a grid survey of surface gamma ray exposures on the <br />disturbed ground in the vicinity of the Last Chance Mine on Davis Mesa, Montrose County, <br />Colorado. The purpose was to establish background radiation measurements for post reclamation <br />comparisons. The Last Chance Mine was discovered based upon surface radiation and drilling <br />surveys and does exhibit generally high radiation anomalies in the outcrops of the Morrison Salt <br />Wash sandstone host rock. <br />Grid survey lines were established by Brunton compass and tape measure across the general <br />disturbed area and marked by stakes and paint on select rock outcrops. The grid was established at <br />25 foot centers over the loading area, haulage road, and temporary ore stockpile; and at 50 foot <br />centers in the adjacent area and waste rock dump site. GPS coordinates were established for general <br />location with a Garmin etrex Vista handheld unit, but the map was constructed using a photographic <br />base map with visible structures and the more accurate taped coordinates. <br />The posted gamma ray counts were taken with an RS-125 Scintillometer. Gross counts per second <br />(cps) were compared with CDPHE's instrument readings of microrems/hr as follows: <br />U-S mrems/hr <br />200 8 <br />1800 90 <br />5500 345 <br />6300 260 <br />Generally soil covered surface in the trees averaged about 300cps. The waste rock dump averaged <br />1454 cps and the loading area and exposed ore rock averaged 2946 cps.