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source for the early stages of the planned VRI processing operations. As a point of reference, <br /> Exhibit T— Environmental Protection Plan (within DRMS Permit No. M2009-076), in addressing <br /> Rule 6.4.20(6)(c), establishes that there are an estimated "8,000 tons of pre-existing abandoned <br /> mine waste rock currently contained within the proposed tailing impoundment area". <br /> Prior analysis of a representative composite sample of these waste rock materials (comprising a <br /> total of 1,079 lbs, or approximately Y.—ton) [refer also to Exhibit C (Appendix Item #1) of DRMS <br /> Permit No. M2009-076] demonstrates that the waste rock materials, particularly if isolated and <br /> maintained within the designated EPF area, do not pose an environmental concern. <br /> This prior analysis included Synthetic Precipitation Leach Procedure (SPLP)testing on the waste <br /> rock materials (carried out in August 2009), in the following manner (see DRMS Permit No. <br /> M2009-076-Exhibit C: "Waste Stream Characterization"—Pilot Plant Sampling Test Description): <br /> "This particular (waste rock) sample was collected by filling 20 five-gallon buckets with <br /> waste rock from the surface and subsurface of the abandoned mine waste rock dump <br /> located within the Tailings Impoundment area (see Exhibit Q. Each bucket is(was) filled <br /> on a grid pattem of approximately 20 yards, representing an average of the contents of <br /> the dump. <br /> The material was then run through a two-stage dry crushing process consisting of- 10"x <br /> 20"jaw crusher that dresses the material down to-314 inches and a 24"x 14"roll crusher <br /> that further dresses the material to -118". The crushed material is (was) then weighed. <br /> This sample yielded 1,079 pounds of dry crushed material, with a density of approximately <br /> 1.5 tons✓cubic yard. <br /> Each bucket is (was) then fed into the hopper of a variable speed screw conveyer that <br /> feeds into a 2' diameter x 4' ball mill. Municipal water is (was) then added at a rate of <br /> approximately 0.5 gpm to achieve 60% to 70% solids by weight. The output of the ball <br /> mill averages 35 mesh, but some coarser material is present. A 1-liter sample of this <br /> slung, referred to as "Raw-Before Treatment'; was collected in a clean plastic bottle at the <br /> ball mill discharge. Some coarser material is (was) captured in a screen box at the ball <br /> mill discharge, and is (was) manually collected and fed back into the ball mill for <br /> regrinding". <br /> The"raw solids"sample(i.e.,the crushed and milled waste rock)obtained in the foregoing manner <br /> was then submitted to Evergreen Analytical, Inc. of Wheat Ridge, Colorado for SPLP analyses <br /> for arsenic, barium, cadmium, chromium, copper, lead, manganese, selenium, silver and zinc <br /> (Method SW1 31 2/601 013) and mercury(Method SW1312/7470A), respectively. All analytes, with <br /> the exception of barium, manganese, and zinc returned results of"U" (i.e., compound analyzed <br /> for but not detected). <br /> VRI subsequently completed a pilot-scale gravity separation process which produced both a solid <br /> tailing matrix and a tailing water component. With respect to the solid matrix portion of the tailing, <br /> 5 <br />