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CGRS,Inc. • <br /> ' much less than those resulting from the SELP testing, which was a more aggressive test. Boron, <br /> fluoride and manganese appeared to be the most leachable analytes in this test. <br /> ' 3.3 "Synthetic Ground Water Leaching Procedure"(SGLP) <br /> Analytical results for the SUP are presented in Table 4. Water was obtained from the gravel <br /> ' quarry pond immediately adjacent from the proposed study area (Figure 3) and was used as the <br /> leaching fluid. This water is considered to be representative of local groundwater quality and was <br /> analyzed to determine background water quality of the leaching medium. A review of Table 4 <br /> shows that the only analytes that were in excess of any standards were boron, manganese, <br /> selenium, fluoride, sulfate and nitrite. The water obtained from the quarry had sulfate and fluoride <br /> ' concentrations of 2,900 and 4 m(, respectively. These concentrations are considered high enough <br /> to inhibit leaching of these analytes to the surrounding groundwater regime. <br /> 1 <br /> 3.4 "Synthetic Groundwater Column Leaching Procedure" (SGCLP) <br /> ' The results for the SGCLP are presented in Table 5. A review of Table 5 shows that boron is the <br /> most leachable element with fluoride and sulfate being the most prevalent nonmetal constituents in <br /> ' excess of applicable standards. With the exception of aluminum and barium all constituents of <br /> concern decreased dramatically with respect to increasing pore volumes. It appears that variations <br /> ' in pH may have had a slight affect on leachability of different coal ash samples. <br /> ' 3.5 Overview of Laboratory Data <br /> The various testing regimes document hydraulic and leaching characteristics of coal ash. <br /> ' Permeabilities of coal ash varied over three orders of magnitude. The hydraulic conductivity of <br /> bottom ash closely approximated recycled concrete and recycled asphalt and is comparable to <br /> ' permeabilities associated with medium and coarse-grained sands. Fly ash samples were three <br /> orders of magnitude less permeable than bottom ash and non-ash samples and have permeabilities <br /> comparable with silt and clay. <br /> ' In general, the most prevalent elements or compounds detected in the leaching studies coincide with <br /> the general composition of coal ash (aluminum, barium, boron, iron and manganese). The intent of <br /> ' SELP study was to determine the maximum leachability of coal ash under different saturated <br /> environments — namely different pH values. Fluctuations in pH did seem to have ap at''ert on the <br /> l/ <br /> 8 <br />