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Boron - The average boron concentration was found to be 0.6 ppm with a range of 0.2 to 1.2 ppm, and 0.014 to 0.049 <br />ppm with an average of 0.026 for the Wadge and Wolf Creek units, respectively. According to the guidelines used by <br />the Montana Department of State Lands, the suspect level of this parameter is 8ppm. Since all boron values are well <br />below this value, no potential concerns related to boron are anticipated. <br />Nitrate Nitrogen - The range of nitrate nitrogen content of the Wadge and Wolf Creek samples was found to be from <br />than 0.02 up to 6.35 ppm (Wolf Creek samples were all below detection limits). According to the guidelines of the <br />Montana Department of State Lands, the suspect level for nitrate nitrogen is a value greater than 20 ppm. None of the <br />values reached this level. <br />Nitrite Nitrogen - Only two of the twenty -six Wadge samples collected were above the laboratory detection limit of <br />0.1. Given the low nitrite nitrogen values, no reclamation concerns are anticipated. <br />Selenium - Only nine of the twenty -six samples Wadge samples analyzed were above the laboratory detection limit of <br />0.01 ppm, with the highest concentration being only 0.2 ppm (all Wolf Creek samples were below detection limits). <br />Due to the presence of such low selenium values, no reclamation or water quality concerns are anticipated relative to <br />selenium. <br />Textural Analysis - The average particle size of all fifteen Wadge samples analyzed was 58 percent sand, 28 percent <br />silt and 14 percent clay, which yielded an average texture of sandy loam. The Wolf Creek samples averaged 22 <br />percent sand, 60 percent silt, and 18 percent clay, with an average textural classification of silty loam. These textural <br />classifications, according to the Wyoming DEQ, are rated fair for revegetation suitability. This is little likelihood that <br />any adverse impacts on revegetation success or water quality can be expected due to texture. <br />Total Combustible Solids - The average total combustible solids of all twenty -six Wadge samples was 6.2 percent. <br />The range of the twenty -six samples is from 0.95 to 10.3 percent. For the Wolf Creek samples, total combustible <br />solids ranged from 0.95 to 8.48, averaging 4.39. The potential of these strata presenting a fire hazard remains remote. <br />Saturation Percentage - The average saturation percentage of the nine Wadge samples was 31 percent with a range <br />of 26 to 40 percent, and 32.4 to 51, averaging 37.3 for the Wolf Creek samples. According to the Wyoming <br />Guidelines, overburden with saturation percentages of 25 to 80 is considered to have a good to fair reclamation <br />suitability. <br />Sodium Adsorption Ratio - The average of the twenty -six Wadge samples analyzed was 15.7 with a range of 8.7 to <br />30. For the Wolf Creek samples, SAR ranged from 8.71 to 16. 1, averaging 11.8. At face value, these analysis results <br />appear to indicate an increased potential for SAR- related revegetation issues; however, this consideration is balanced <br />by the fact that the salinity hazard, as predicted by the electrical conductivity analysis results, is very low. Given the <br />apparent discrepancy between SAR values, and salinity potential, as measured by electrical conductivity, Dr. Sterling <br />Olsen, a Soils Scientist with the USDA Agricultural Research Service at Colorado State University, was consulted. <br />Results of the Dr. Olsen's data analysis and review indicate that application of sampling and analysis techniques <br />developed for surface agricultural soils to un- weathered overburden may give unreliable results relative to SAR and <br />salinity hazard. Specifically, the calcium values obtained from the analyses are abnormally lower than would be <br />expected. The average calcium concentration was found to be 158 meq /1 and, according to Dr. Olsen, the solubility of <br />calcium is correlated with the amount of carbon dioxide present in the atmosphere. The concentration of calcium <br />when it is in equilibrium with air, at a pH of 7, should equal 7 meq /1. Dr. Olsen stated that once the coal refuse <br />material is exposed to the atmosphere, the concentration of calcium will increase and SAR will decrease due to the <br />competition of the two cations for the same exchange sites. With an increase in calcium to a minimal concentration of <br />7 meq /1, average SAR values can be expected to decrease from 15.7 to around 6.6. Calcium in excess of 7 meq /1 will <br />result in even lower SAR values. SAR values for weathered overburden materials from overburden data collected in <br />this same area and previously discussed in the CYCC Permit Application No. 79 -177, support this evaluation and <br />conclusions. <br />TR13 -83 2.04 -17.1 11/03/14 <br />