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density and size of vegetation is inverselyproportional to the steepness of the slopes and the <br /> presence of solid gypsum rock outcroppings. <br /> NRCS soil group boundaries correlate well with vegetation (Drawing 05. Section 5.8j)� Soil <br /> Group (high runoff and low infiltration) areas are typically devoid Of vegetation vvhika Soil <br /> Group B (fairly low runoff and higher infiltration)areas are more highly vegetated. Steeper slopes <br /> typically have little to no vegetetion, aa they typically consist ofgypsum outcrops orare crusted <br /> with gypoite. Based on aerial photography and site reconnaissance, the southern extent ofthe <br /> proposed Upper Pit expansion consists mostly ofgypsum outcrops orgypaite and little to no <br /> vegetation ie present. Similarly, the southern portion of the East Pit area is comprised ofgypsum <br /> outcrops or gypsite,while the northern portion shows signs of vegetation. There are also biological <br /> mOi| crusts (consisting of algae, fungi, and lichens) throughout the proposed disturbance area. <br /> Juniper and pinion trees cleared ahead of the active mining area would be utilized in the <br /> o8c|annodon process. Pinion and juniper slash o|88rad at the existing Mine have added success <br /> to revegetotiOn plots. The technique has consisted of placing slash over plots graded with volcanic <br /> ash growth medium and then seeding the plot. The slash has shown to aid r8veg6tahon by <br /> providing shade for the early aeed|inge, helping to stabilize and control erosion of the piote, and <br /> eventually adding organic nutrients heCk into the soil. <br /> 5'6-1 Relationship of Vegetation to Soil Types <br /> The steep slopes encrusted with gypaite support virtually no vegetation. Huvxever, flatter areas <br /> tend to be layered by o thin cruet of volcanic ash that varies from depths of 3 inches to several <br /> feet in some areas. This volcanic ash was apparently deposited over the area during the last <br /> active period of the Dotsero volcano.The volcanic ash essentially serves as the indigenous topsoil <br /> for the area and supports the growth of the pinion and juniper stands in the flatter area. Deposits <br /> of the volcanic ash tend to onour in basins that intermingle with hummocks of gypsum <br /> outcroppings. Hummock units vary from 4 to 20 haat in noaxinnunn dimension. <br /> Successful reclamation efforts at the existing operation have shown that the indigenous volcanic <br /> ash can be utilized asa growth medium. The procedure in that area has consisted Vfremoving <br /> volcanic ash basins ahead of the active mining area and stockpiling this material for later use in <br /> reclamation. There is enough organic content in the ash to support the growth Of dry land <br /> vegetation. Successful reclamation plots (located on the east side of the Lower Pit and northeast <br /> corner ofthe Upper Pit based on field observations) were previously realized at the existing <br /> operation with 8 seed mixture consisting Of Indian Rice Grass (Nezpar)' Crit8n8 ThiokSpik8 <br /> VVh8@tQraSG' SodarStraamo B8nkVVheatgnaoo. and Salina Wild Rye (Centex, 2001>. This Seed <br /> mixture was used historically but is not proposed as part of this Modification. <br /> 5,7 Fish and Wildlife <br /> There are no perennial streams or water bodies near the Mine, so there is no habitat for fish. The <br /> nearest perennial stream is Eagle River, south of 1-70. about a mile dovvns|ope from the Mine. <br /> Short-term runoff does occur during rare major storms and would be captured by mtornnvvater <br /> management systems. Beat management practices are in place at the Mine for the protection of <br /> surface water resources. <br /> 48 <br />