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3.2 Network and Configuration <br />3.2.1 Pre-Mining State <br />Runoff from the pre-mined AVF likely discharged in to Stollsteimer Creek along the entire <br />length of the western boarder. In this demonstration, flows are collected at the inlet of <br />Sedimentation Trap A via Ditches lA and 1B and direct flow for a comparison of pre-mined <br />and reclaimed conditions. <br />3.2.2 Reclaimed State <br />Runoff practically ponds on a hay field, and eventually migrates through shallow swales via <br />Ditches lA and 1B to Sediment Trap A. After reclamation of the Ditches and Sediment <br />Trap, runoff will migrate to Stollsteimer Creek along the western boarder of the area, similar <br />to pre-mining conditions. <br />3.3 Soils <br />Nunn soils are characteristic of the AVF area (see Paragraph 2.2). <br />3.4 Land Use Condition (LUC) <br />Reference is made to Paragraph 2.4. A LUC of 1 is used for the hay field. 6 for <br />concentrated flows across the hav field, and 8 in the diversion ditches. <br />3.5 Curve Number (CN) <br />3.5.1 Pre-mined State <br />A CN value of 74 was determined for the AVF Reference Area, and is used in one scenario <br />to consider the AVF in its pre-mined state (see Paragraph 2.7). Information in Appendix <br />IV, Permit Information for Irrigated Pasture, indicates that the pre-mining vegetative cover <br />of the alluvia] valley floor area was variab]e, probably due to uneven distribution of <br />irrigation, ranging from significantly drier (and sparse vegetation) to a much wetter (rushes) <br />depression area. The area is further described as overgrazed (consistently), and high <br />percentages of species such as dandelion, chicory, and bindweed were indications of poor <br />management practices. A second scenario is developed that recognizes this condition with <br />a CN of 75 to recognize pre-mining conditions (Permit Conditions). <br />3.5.2 Reclaimed State <br />Two areas of the 1996 Vegetation Survey (1990 and 1991 seedings) are combined to <br />represent the reclaimed AVF area in this demonstration. Ground cover is 87%. Located <br />Page 10 of 34, 7 Oct 96 <br />