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<br />-3- <br />B. Soils and Revegetation - Rule 4.15 <br />There appears to be some discrepancies and uncertainties regarding <br />disturbed area "soil" analyses, and as a result the suitability of <br />on-site material to serve as a plant growth medium after final <br />grading of pre-law disturbance areas is somewhat in question. <br />Two separate groups of analyses are included in the permit. <br />Composite samples collected in June, 1980, indicate potentially <br />toxic levels of boron, lead, and nickel. Other metals for which <br />pant toxicity levels are not well defined also appear inordinately <br />high, for either soil or overburden material. Sodium adsorption <br />rations (SARs) and electroconductivity (EC) levels are quite low, <br />however, and would indicate no potential restrictions to plant <br />growth. <br />Analysis of soil samples from the same area obtained in May, 1983, <br />show similarly low SARs, but extremely high electroconductivities <br />(over 100 mmhos/cm). Based on relatively low calcium, magnesium <br />and sodium levels in the 1983 analyses, however, it would appear <br />that conductivity readings were in micromhos, and were mistakenly <br />labeled as millimhos. <br />There is a statement in the application indicating that heavy metal <br />concentrations in the 1980 analyses appeared high due to the acid <br />extraction technique employed, and that subsequent analyses using <br />standard extraction techniques indicated significantly lowered <br />metal concentrations. However, with the exception of boron, metal <br />analyses were not provided with the 1983 data in the permit. The <br />1983 data show boron levels to be well below published suspect <br />levels. <br />The following requirements are necessary to resolve this issue and <br />ensure the feasibility of reclamation: <br />1. The permittee should submit the referenced data on metals which <br />was analyzed by standard procedures, if that data is <br />available. Extraction method should be noted. <br />2. If the above data is not available, composite samples from the <br />same areas sampled previously should be obtained and analyzed <br />for zinc, copper, iron, manganese, lead, molybdenum and <br />nickel. AB-DTPA extract should be employed. <br />3. The permittee should review the 1983 data, and if conductivity <br />levels were actually expressed as micromhos rather than <br />millimhos corrected tables should be submitted for insertion in <br />the permit. <br />