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I I I I I I 'I' I I I I I I I I I I I I 0021'"'3 2.0 EROSION SURVEY METHODS 2.1 Erosion Survey Methodology In order to assess the extent and condition of eroded areas, the area within the FERC project boundary was evaluated by a pedestrian survey, Although the upland areas were assessed for signs of erosion, the survey focused primarily on the reservoir edge and the Williams Fork River. Based on the characteristics of the Williams Fork Project, it was anticipated that the greatest erosion potential would occur along the reservoir bank or the stream bank, The length of the reservoir edge was traversed on foot and assessed for evidence of erosion, Access to the reservoir edge was gained either via the beach (if present) or the top of the reservoir bank, Upon discovering an erosion site, the length of the reservoir bank affected by erosion was traversed on foot, and GPS data were collected using the methods described in Section 2.2. Each erosion site was given a unique numerical identifier and was assessed for the following characteristics, These data were entered into a field data form prepared specifically for this survey, Upon completion of the erosion survey, these data were transferred from the data forms into a Microsoft Excel spreadsheet (Appendix A) for inclusion into the GIS database. Photo documentation was also collected for each erosion site. Sile Type Based on initial site visits prior to conducting the survey, it was anticipated that three erosion site types had potential to occur within the FERC project boundary: reservoir bank, stream bank, and intermittent/overland drainage. Reservoir bank sites encompass erosion occurring along the Williams Fork Reservoir edge, and stream bank sites include erosion occurring along the Williams Fork River as it flows into the reservoir. Intermittent/Overland Drainage erosion was considered possible on upland areas and roads located within the FERC project boundary, Soil Composition Soil composition was assessed for each erosion site to aid in determining both cause of erosion and the potential for further erosion occurring at that site, Characteristics observed when assessing soil composition include substrate type (Sandy, Clay, etc.), presence and size of gravel, presence and size of cobble, and presence of vegetative materials (root systems), Sial us or Condition (Active or Inactive) Each erosion site was concluded to be either active or inactive. Active sites were determined by the presence of recently eroded soil and plant material, the observation of Williams Fork ReservOIr Hydroelectric Project Janutlry 2004 Srelgers Corporation Erosion Survey Repurt Page 2