1997-07-14_REVISION - M1988112 - Laserfiche WebLink

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BATTLE MOUNTAIN RESOURCES Pagc 9-2 San Luis Protect Technical SpeciCcations maintain required gradients and flow line elevations. Side slopes depths in excess. of 5 feet shall extend to the surface a[ 3H:1 V. Ditches shall be lined with riprap Material Type `and underlain by a geotextile fabric, as shown in the Drawings. Relocation of ditches, changes in gradients, or changes cross-sections must be al+proved by the Designer. 9.1.2 Spillway e>r o ~- The tailings impoundment spillway is a composite 35-ft weir with a 10-ft wide trapezoidal discharge channel running through [he center. The composite control section is shown in the Drawings. The control section for the spillway is at elevation 8590. The channel c:ut through the control section shall have 2H:IV side slopes. Side slopes cut in [he embankment above the control elevation shall be at 3H:1V. The embankment slopes and ditch through the perimeter berm (Sta. 0+00 to ]+50) shall be protected with Material Type 6 riprap, as shown in the Drawings. An erodible berm shall be constructed to the [op of the channel, +~verlaying the riprap, along the centerline of the original crest of the perimeter berm. The erodible berm shall exist until reclamation of the seepage pool to serve as a spillway discharge pond is complete. The control will initially serve as an emergency spillway with an invert elevation o f 8590. The spillway discharge channel consists of a trapezoidal section with a 10-ft base and 2H:1V side slopes below a 35-ft wide channel. Minimum depths and the layout for each section are shown in the Drawings. The side slopes for the 35-foot channel shall be based on the material excavated as described in Section 5.1.3 of these Specifications. Special irovisions for excavation of the channel aze described in Section 2.10 of these Specifications. FI 11 sections are not anticipated, except after entering the discharge pond. Fill sections shall be completed in accordance with Section 6.11.2 of these Specifications. Side slopes for fill sections in the spillway channel, if required, shall be at 2.SH:1 V or flatter using Material Type 2 unless otherwise specified in the Drawings or approved by the Designer. The mild spillway section (Sta. 0+00 to 6+00) shall be at a 0.5 percent gradient and shall be protected by Material Type 4 riprap. The riprap is underlain by a geotextile fabric as shown in the Drawings and defined in Section 7.0. Erosion control in the steep spillway section (Sta. 6+00 to End) shall consist of a grouted riprap blanket, bedding, and geotextile fabric as defined in Section 8.0 of these Specifications. Channel alignment and special provisions are detailed in N:\DHALLMAN\SANLUIS~SANLUIS.DOC 9-Z SRK ProjectNo. 14772