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<br />Erosion control methods to be utilized throughout the project include gabions, <br />waterbars, sediment barriers, mulch, and erosion control fabric and riprap, as <br />applicable, as well as restriction of access. These methods are described below. <br />• Gabions: In smaller intermittent channels, gabions (wire baskets filled with <br />large cobbles and rocks) would be placed downstream of the channel to slow scour <br />action and trap sediment. In larger channels, a downstream gabion structure would be <br />installed, the eroded area backfilled, and another gabion structure placed upstream of <br />the backfilled area to slow scour action and trap sediment. <br />• Waterbars: Waterbars will be constructed on pipeline ascent/decent slopes and <br />in areas of erodible soils to direct runoff from the disturbed areas to adjacent vegetation <br />or rock, thereby minimizing erosional channels and sediment transport prior to the <br />reestablishment of vegetation. Waterbars will be of sufficient size to last at least 5 years <br />and will be constructed at spacing intervals indicated in the table below. <br />Table 1 Spacing Intervals for Waterbars <br />,Grade of Slope Spacinglntervals <br />Less than 1 percent 400 feet <br />1 - 5 percent 300 feet <br />5 -15 percent 200 feet <br />15 - 25 percent 100 feet <br />Exceptions to this will be as follows: If the ROW has a side slope greater than or equal <br />to one-third of the slope along the length of the ROW, waterbars will not be <br />constructed. For example, if a ROW slope were 6 percent along its length and less than <br />2 percent across its width, waterbars would not be necessary. However, if the side <br />slope were 2 percent or more, the pipeline trench berm would be cut to ground level at <br />50-yard intervals and at each drainage crossing. <br />Waterbars will also be installed at the entrance and exit of all stream and wetland <br />crossings. Topsoil will not be used in the construction of waterbars. <br />• Sediment Barriers: Sediment barriers will be installed at the entrance and exit of <br />streams and wetlands to minimize sediment transport into these sensitive areas. <br />Certified weed-free straw bales or similar manufactured products will be used for these <br />installations. <br />• Mulch: Site-specific applications of mulch will be made to control erosion. The <br />mulch will be spread across the ROW, temporary use areas, and laydown areas as <br />needed. Mulch may include: <br />PipeLne Reclamation Plan <br />YaNree GWch:4ium Minerals Proven <br />American Sofa. L.L.P. <br />