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regrading work has been covered in other sections of the Special Conditions. A tracezoidal shaped drainage channel shall be constructed beginning at the approximate crest of the portal bench cut slope immediately above the bypass culvert inlet and extending downsloce to the base of the portal bench fill slope in the area where the bypass culvert access manway is located (see dwg. sheet 20 of 30). The channel shall be constructed to tie in to the portion of the bypass culvert passing beneath the highway by constructing a new inlet for the bypass culvert. Anew outlet end to the by pass culvert shall be constructed on the south side of the highway by excavating down to the base of the existing culvert, removing or collapsing a portion of the lower segment, and grading around the new outlet end sufficiently to tie in with and provide a smooth transition for runoff into the second drainage channel segment. The second channel segment shall be constructed beginning at the new culvert outlet end on the south side of the highway and extending downsloce to the point where the existing bypass culvert passes beneath the rail line. The lower portion of this channel shall be constructed to tie in to a second culvert inlet constructed on the existing bypass culvert by excavating down to the base of the culvert, removing a portion of the upper segment, and grading around the new inlet end sufficiently to provide a smooth transition for runoff into the new inlet. Both drainage channel segments shall be constructed by grading the hillsloce to form a trapezoidal shaped drainage channel 3 ft. deep and 4 ft. wide (bottom width) with 2h:ly side slopes as shown on Exhibit 6D. The channel bottom and sides shall oe lined with minimum 1 ft. diameter durable rock riprap. The specified channel depth and width are the finished dimensions wit11 riprap in place; excavated dimensions will be greater in order to provide space for riprap. The finished channel bottom elevations at all culvert inlet and outlet ends shall be aligned with the bottom elevations of the culverts. The longitudinal center line of the channels shall be aligned with the longi tudinal center 1 ine of the culverts at the inlet and outlet ends. B. Highway and Rail Line Drainage Ditches All portions of the highway and rail line drainage ditches which nave been affected by regrading work, ripping work, or other construction activities associated with this project shall be re-established to a configuration that provides adequate drainage control and that is consistent with the configuration of the ditches located outside of the project area. 7.3 Measurement and Payment No measurement for payment shall be made for this bid item. Payment shall be made for the lump sum bid price. The price bid shall include all of the CONTRACTOR'S cost of whatever nature to complete the above described work in accordance with the specifications. -21-