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170.09 "L" TOPOGRAPHY CROSS SECTIONS. Cross sections shall be taken at <br /> right angles to tangents and normal to curves at every staked point in the <br /> "L" profile system. Hand levels, Rhodes arcs, or engineer's levels may `>e <br /> used to establish the Elevations at significant breaks in topography, at <br /> breaks in the designed roadway template, and at reference points. Ground <br /> shots for these cross sections shall be recorded in terms of plus or minus <br /> rods from ground at L-centerline and in terms of horizontal distances from <br /> L-centerline. Cross sections shall be measured and recorded to the nearest <br /> 0. 1 foot in elevation and, nearest. foot in horizontal distance, and shall <br /> 170 extend approximately 20 feet beyond the designed clearing and grubbing <br /> .09 limit on cut sections and approximately 20 feet beyond the toe of fill on <br /> fill sections. Reference point hubs shall be set at each end of the cross <br /> sections with guard stakes showing centerline station and the distance to <br /> the centerline. Reference stakes shall be marked as shown in Figure 170-1 . <br /> Each reference hub shall be marked with a 4-foot lath with painted top or <br /> plastic flagging. <br /> If the Contractor elects to set slope stakes during the "L" topography <br /> cross section phase of the work, these stakes may be subject to relocdtinn <br /> to adjust earthwork quantities. <br /> 170.10 SLOPE STAKES, CLEARING LIMITS, AND REFERENCE STAKES. Slope stakf•:; <br /> shall be established on one or both sides of the centerline, as SHOWN ON <br /> THE DRAWINGS, at each "L" station established. These stakes shall be -:et <br /> within the tolerances shown on Table 170-2. The position of these stakes <br /> shall be determined by hand level methods applied to the designed typical <br /> sections and the new ground elevations, or "catchpoint" printouts. If. t1-1- <br /> theoretical and actual points differ by more than 1 foot in horizontal or <br /> vertical distance , slope stake points shall be checked for error and c,>r- <br /> rected. The cut or fill and horizontal distance to centerline, to bottom <br /> of ditch, or to shoulder grade as DESIGNATED by the Forest Service, shall <br /> be recorded on the slope stakes and in the slope stake book as shown on <br /> Figure 170-2. <br /> Clearing limits shall be set on both sides of the centerline at each <br /> established "L" station within the tolerances shown on Table 170-2. The <br /> clearing limit shall be located on the ground to the dimensions SHOWN ON <br /> THE DRAWINGS. This point shall be marked on the ground by lath and flag- <br /> ging, or other approved methods. The total horizontal distance from the <br /> centerline to the clearing lath at each section shall be recorded to the <br /> nearest foot in the field book. <br /> After the slope staking is completed, the Contractor shall record on t.� • <br /> cross section reference guard stakes the vertical distance from the R. P. t <br /> the construction grade, at a minimum horizontal distance of 15 feet <br /> the clearing limits. The difference in elevation between the slope st -i' <br /> and the hub, or reference stake, shall be taken and the cut or fill •in : <br /> horizontal distance to either the centerline, the bottom of ditch, or the <br /> shoulder grade as DESIGNATED, shall be recorded on the guard stake ant :;. <br /> the slope stake book. (See Figure 170-2. ) <br /> 170. 11 STAKING CULVERTS. All culverts shall be staked with huhs driv. i, <br /> the centerline of the culverts approximately 10 feet from each emi . In <br /> addition, a guard stake shall be set at each hub and shall be marked wit ' <br /> the following : <br /> 30 <br />