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April 2014 16 10381640A <br />4.2.1 Bulk Testing <br />Solid -phase chemical analysis was performed on the soil and rock samples collected during the 2012 field <br />program. The chemical analysis was performed in a two -step process including digestion of the sample in <br />acid to release the elements into the solution phase (EPA Method M3010A) followed by analysis of the <br />elements in the resulting digestion by inductively coupled plasma mass spectrometry (ICP -MS; EPA <br />Method M6020). The results from solid -phase chemical analysis were used to make an inference <br />regarding elements of potential environmental concern, although it should be understood that a high <br />concentration of a particular element does not necessarily imply that this element will indeed be mobilized <br />in concentrations that may lead to environmental impacts. The elemental compound concentrations from <br />the solid -phase analysis are detailed in Table 10 and the laboratory summaries are in Appendix E. <br />Schoeller diagrams are provided in Figure 5 through Figure 8. <br />Additionally, samples of the CKD materials were analyzed for total metals once in 1991 and then quarterly <br />beginning in the first quarter of 1993 through the first quarter of 2002, with the exception of 1994. These <br />results are provided in Appendix E and summary statistics are provided in Table 11. <br />Concentrations reported for the CKD testing conducted by Golder and the quarterly testing by Holcim are <br />within the same range of values. The CKD material has elemental compounds that are higher than the <br />native materials, including: boron, calcium, lead, potassium, selenium, thallium, and zinc. The lead, <br />selenium and thallium concentrations are elevated by at least a full order of magnitude. The CKD <br />materials exhibited concentrations of arsenic, barium, chromium, and manganese that were similar to or <br />less than the native materials. The concentrations of arsenic, barium, copper, manganese, thallium, <br />uranium and zinc are greater in the CKD and native materials than in published concentrations for <br />carbonates and sandstones (Price 1997). <br />4.2.2 Synthetic Precipitation Leaching Procedure <br />The SPLP is a test where material such as soil or rock is saturated with a solution designed to mimic <br />meteoric water or natural weathering solutions. The materials undergo grain size reduction such that all <br />components pass a 0.375" sieve. The solution to rock ratio is 20 to 1, and the test concludes after <br />18 hours, at which point the leachate is collected. The chemical composition of the leachate is analyzed <br />for the constituents of interest. Metals are generally analyzed by US EPA Methods 200.7 or 200.8 by ICP <br />or ICP -MS, respectively. The leachate solution has a weakly acidic pH of 5.0 to approximate rainfall <br />(extraction fluid #2 in US EPA Method 1312). The test is not designed to definitively predict long term <br />water quality associated a material, as this is complicated by a number of variables such as surface area <br />exposure, weathering rates, flow rates, and actual water to rock ratios. <br />`' Golder <br />is \10 \81640a\ 0400 \gwcharwellinstallfieldrep_fnl 30apr14 \10381640a gwcharrp[_holcim boettcher_fnl 28apr14 with holcim edits.docx <br />Associates <br />