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This sequence of operations will cycle across the well field as mining panels are developed and retired. Retirement and reclamation of mining panels is discussed in the Reclamation Section 5.0 of this document. Duting all phases of project development and operation, appropriate erosion and sediment control measures will be constructed and maintained. The principal BMPs that will be used during well Feld operation include silt fencing, channels and diversions, level spreaders, check dams, sediment traps, drop structures, water bars establishment of interim vegetation, vegetative filters, surface roughening, geotextile fabrics and mulching. These methods and structures may be used individually or in combination to effectively control erosion and sedimentation. Silt fencing will be placed as a temporary perimeter erosion and sedimentation control while solution wells are developed and placed into operation. Silt fencing will be used to treat water from disturbance associated with the construction of well pads, access roads, solution collector pipes and pumping stations. When concentrated drainages are encountered, diversions will be used to route runoff around the disturbed area. When it is not feasible to divert flows, runoff will be routed through disturbed areas via properly designed and constructed channels. Check dams with pervious outlets may be used to release water from disturbed area diversions, channels and silt fences. Channel linings will be provided as needed based upon flow velocities to ensure diversions and channels are erosionally stable and to prevent excessive sedimentation. Level spreaders may be placed at the outlets of minor diversions, channels and road ditches to disperse concentrated flows and provide irrigation for downslope vegetation. Level spreaders will work best for structures that are expected to cant' 10 cfs or less. In moderately sized channels it may be necessary to use sediment traps and drop structures to control erosion and sedimentation. Moderately sized channels typically cant' 10 to 250 cfs. In larger channels where peak Flows are expected to exceed 250 cfs, check dams may be placed to control channel gradients and cross sections, and prevent excessive erosion. These check dams may be constructed using v;vious materials depending upon the anticipated operational life of the structure and the estimated peak flow. Water bars may be used to collect and divert storm water runoff across and away from well pads, access roads, and solution collector pipelines during the operational life of a mining panel. Their successful use depends upon adequate construction at frequent intervals determined by slope (Tabled). After development disturbance is completed, silt fencing will be systematically replaced with more permanent, lower maintenance erosion trnd sediment control methods and structures. Cut and fill slopes may have their surfaces roughened using plowing, ripping, land imprinting or contour Furrowing operations. Roughening will provide erosion and sediment controls while longer-term measures, such as the establishment of interim revegetation and vegetative filters, are implemented. Interim vegetation may be established on disturbed areas outside of normal traffic ways. Mulch and surface amendments may be applied to promote vegetation establishment and growth. On disturbed slopes steeper than 2h:ly, geotextile fabrics may be used in conjunction with the establishment of interim revegetation seed mixtures to control erosion and sedimentation, while helping to promote vegetation growth and establishment. Interseedings to establish or enhance vegetative filters at the bottoms of disturbed outslopes may also be performed. American Sala. L.L.P. '1-~ Soil Conscrvatwn. FJOSIOn and Sediment Cantml. Reclamation, and Revegetatmn Plan ()ctobcr 28. 1998 Rcvtsed April 9, 1999