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JD -6 Mine Environmental Protection Plan 8 <br />Table 3. Samples Collected and Composited for Geochemical Testing <br />Northing _y <br />584,990 <br />585,095 <br />585,185 <br />Composite ID Samples <br />JD -6 -WRP 1 <br />JD -6 -WRP JD- 6 -WRP2 <br />JD- 6 -WRP3 <br />Notes: WRP = representative underground mine waste rock pile composite <br />Sample coordinates given in State Plane Colorado South NAD 27 ft <br />The individual samples were crushed to -3/4 inch using a jaw crusher in Whetstone's geochemistry <br />facilities in Gunnison, Colorado. The samples were subsequently split using a Versa Splitter (riffle -type <br />splitter) followed by a cone and quartering method and then composited to develop the representative <br />composite samples shown in Table 4 for the underground mine waste rock (JD -6 WRP). <br />Cone - and - quarter compositing and splitting were performed by gathering the sample into a pile (cone), <br />digging out the center of the cone and distributing the material around the edges of the pile in a ring, and <br />gathering the ring back into a center cone. The procedure homogenizes the sample and was repeated three <br />times. The cones were then split into equal quarters, and opposite quarters were combined to produce a <br />representative split. Sequential generations of splits were combined until the sample for the composite was <br />within the target weight. <br />The samples were then crushed further to approximately minus 10 Mesh in an impact mill and split using <br />the cone and quartering method to obtain the weights shown in Table 4. <br />The final splits were sent to Energy Laboratories for analysis, with a request to process and analyze them in <br />their entirety. These procedures were implemented to avoid potential sample bias related to shipping, <br />settlement, and unrepresentative splitting at the analytical lab. The resulting composited samples are <br />believed to be representative of the materials of interest. <br />Table 4. Mass of Composited Samples Submitted for SPLP, Whole Rock, and ABA <br />Analysis <br />Composite ID <br />JD -6 -WRP <br />Sample ID <br />JD -6 -WRP SPLP <br />JD -6 -WRP WR <br />JD -6 -WRP ABA <br />Easting_x <br />1,073,230 <br />1,073,315 <br />1,073,215 <br />Weight (g) <br />207.85 <br />112.32 <br />114.64 <br />Notes: WRP = representative underground waste pile composite <br />SPLP = sample designated for synthetic precipitation leaching procedure <br />WR = sample designated for whole rock analysis <br />ABA = sample designated for acid base accounting analysis <br />5.3.3.2 Acid Base Accounting Results <br />Acid -base accounting (ABA) tests were used to evaluate the potential for ore and waste rock material to <br />generate acid rock drainage. Acid -base accounting provides a theoretical estimate of the net acid - <br />producing potential of rock materials by comparing the total acid generating potential (AGP) to total acid <br />neutralizing potential (ANP). Test results are generally evaluated by calculating the net neutralizing <br />potential (NNP = ANP -AGP) or by the ratio of ANP to AGP (ANP /AGP). Samples with NNPs greater <br />than 20 and ANP /AGP ratios greater than 3 are considered to have low potential to produce acid. Samples <br />with NNP values between 0 and 20 and ANP /AGP ratios between 3 and 1 are indeterminate. Samples with <br />negative NNP values and ANP /AGP ratios below 1 are potentially acid generating (EPA, 1994). <br />4148A.120927 Whetstone Associates • <br />