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u <br />Soils Information <br />Existing Reclamation Soil Properties - Minesoils <br />Over the past several yeazs, reclamation has been done at this operation. The results of that <br />reclamation have been varied. In some places spectaculaz growth and vegetation development has <br />occurred, accompanied by strong invasion and growth of trees and shrubs. Interestingly, in other places the <br />growth has been very weak and stunted with virtually no natural invasion. It became clear that some factor <br />or combination of factors in the reclamation environment was determining these differences in growth rate <br />and developmental patterns of the vegetation. Differences in seed mixttrre, seeding method:;, or initial <br />fertilization were immediately ruled out. All sites had been treated the same way. Slope aspect was also <br />eliminated by noting that similarly weak growth occurred on level, east facing, and south facing sites. <br />Furthermore, the strongest growth was found on a south facing slope where the growth would be expected <br />to be the weakest. This interesting and puzzling pattern was investigated. It was reasoned that if the factor <br />or factors that were controlling this pattern could be identified it might be possible to control, to at least <br />some extent, the creation of the reclamation envirorunent. If that could be done then it would increase the <br />success potential in future revegetation efforts. <br />Soil samples were taken from each of these areas. Because stmctural fill (crusher fines) was involved <br />to differing degrees in the production of these growth media, a sample of that material wa< taken from the <br />structural fill stockpile. These samples were sent to the Soil Testing Laboratory at Colorado State <br />University. <br />Routine soil tests were requested on each of the samples. The numerical results of the tests are shown <br />in Table IT-l. Following that table are six bar graphs that correlate the results of these tests with the type <br />of growth found on each site where the soil samples were taken. The term "Growth" when used in these <br />graphs is a qualitative assessment. That is, cover, density, species composition, and overall appearances in <br />combination with invasion rates were mentally combined into a numerical value on a scale of 0 to 5 (zero <br />representing no growth such as on structural fill in the stockpile). This growth value is shown on the Y2 <br />axis (vertical axis on the right side} of each graph. The order of the samples along the X-axis is from <br />lowest growth to highest growth. This allows for an easier examination of any correlations between growth <br />and various soil parameters. Note that there is no growth value for sample MZRS as that sample came <br />from the structural fill stockpile. <br />Examination of the ntmerical data in Table IT-l and the graphs shows that growth is not well <br />correlated to any particular factor, but shows a relationship to some. For example, growth seems to be <br />somewhat inversely related to pH. [t is known that even small changes in pH can have dramatic effects on <br />growth rates. Therefore, it is possible that pH may be showing more influence than the grz.ph would <br />appear to indicate. <br />Growth is also related to organic matter. Unfortunately, organic matter is a complex factor and it <br />cannot be easily determined whether increasing organic matter is a cause or an effect of the growth. As <br />growth and development continues organic matter will naturally rise, even though it possit~ly had little to <br />do with the initiation of that growth. It is concluded, in this case, that the close relationship between <br />growth and organic matter is a consequence of the growth rather than a cause of the growth. <br />There appears to be a slight relationship between growth and potassium, but because potassium is not <br />limiting in these soils it is unlikely that is the cause of the growth differences. Iron shows a similar <br />pattern, but because it is not limiting it is unlikely to be a causal factor. <br />Menzer Quarry Amendment Exhibit I Page 8 <br />