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• • Soils nformation After examination of all the soil test data and concluding that chemistry alone cannot explain the growth patterns seen on revegetation sites that aze two to four years old, it was decided that physical properties may be involved. Texture, in particular, is commonly related to growth in semi-trid vegetation. That is, the finer the soil texture the lower the growth rate. Texture influences moisture rel;ttions in the soil. Fine soils tend to allow faster runoff and therefore the available moisture is reduced. In more coarse soils, rainfall and snowmelt tends to sink into the soil more readily resulting in a higher moisture conservation. Examination of the sites showed that the lowest growth rates were in soils where the structural fill component of the growth medium was high. Soils with fewer fines and more coarse rock stow higher growth values, where time since seeding is equal. For example, the MZR1A and MZR3 sits were occupied by two year growth, but the growth value of MZR3 is much higher than MZR1A even though both have nearly identical slope aspects (south) and similar slope gradients. MZR1A is almost pure structural fill (a fine textured soil) while MZR3 has only a small amount of structural fill and a much larger component of native rock pebbles (a coarse soil texture). Both were judged by the testing lab as being sandy loam but this was because the larger pieces were removed from MZR3 prior u~ chemical testing. That is, only the fine component of MZR3 was provided to the lab for testing. Further examination is being done on this relationship between growth rates and soil texture. It appears there is a relatively narrow texture type that aids in growth acceleration. During revegetation work in Stage l of Phase 1 this texture relationship will be further defined so in later revegetation work that relationship can be used in creating the growth medium. For south facing slopes this relationship may }~e different than on north facing slopes. Therefore, examining existing south facing areas where growth is strong may not provide the kind of information needed to define what is needed on north facing slopes. Nevertheless, the texture of the growth medium in those existing areas where strong growth is currently present can provide at least a clue as to what is needed. Those areas will be thoroughly examined if this amendment is approved. Examining them now would cause disruption of the established reclamation and that would not be desirable in the event the amendment is not approved. If the amendment is approved existing reclaimed areas where strong growth is present will need to be destroyed, so examining those soils p:'ior to mining in those areas would be available without damaging the integrity of existing reclamation. Menzer Quarry Amendment Exhibit I Page 13