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Transit Mix Concrete Co. <br /> The culverts in the major drainages will be located along the current creek alignment and will <br /> match the existing channel grade. The length of the culverts to be installed will be minimized to <br /> reduce the area of the channel that will be affected. Figures G-16 and G-17 show the profile and <br /> cross-section for the crossings of Little Turkey and Deadman Creeks, respectively. <br /> The sediment detention basin outlets will be CMP culverts. These culverts will need to be <br /> excavated through the unmined blocks of bedrock to allow the pipes to be placed at grade. <br /> Therefore, a notch will be excavated to allow the installation of the culverts based on the <br /> maximum depth required for drainage over the life of the pit development. These areas will then <br /> be filled to ensure the disturbed area drainage is detained prior to release. For reclamation, the <br /> fill will be removed and the bedrock cut exposed to allow a positive drainage from the reclaimed <br /> pit areas. Two specific areas are shown on the north pit area with drainage for NP-SP-2 and <br /> NP-SP-3 areas. <br /> Culvert CWC-1 is the only culvert that is not a road crossing or outlet structure. This culvert will <br /> be constructed under a portion of the fines pile fill to allow placement of the fill on the upper <br /> portions of the pile. Once the fines pile is completed, the culvert will be removed and the area <br /> reclaimed. Due to the length concerns have been raised with how to provide maintenance. As <br /> this culvert will be a large diameter and will have a constant slope, it is unlikely that small debris <br /> will be a problem. It is planned that the culvert will have a trash rack at the inlet end that will <br /> protect against large debris plugging the culvert inlet and allow for maintenance during and after <br /> large storms to ensure debris can be removed from the inlet end of the culvert. In the event that <br /> debris bypasses the trash rack and becomes lodged in the culvert, the culvert is large enough <br /> that men and small equipment can enter the culvert for maintenance. The culvert backfill <br /> material will be fines, and Transit Mix has committed to measuring the strength parameters for <br /> this material. Once the strength parameters are known, Transit Mix will provide to CDRMS prior <br /> to installing the culvert loading calculations that demonstrate sufficient wall strength for the depth <br /> of cover. <br /> d. Best Management Practices for Sediment Control <br /> In addition to the primary water management structures, secondary sediment control measures <br /> should be installed to reduce water and sediment loads on the primary ponds. <br /> Best Management Practices (BMPs)for sediment control are standard practices on construction <br /> sites. Unlike the primary water management structures which are designed to remove silt-sized <br /> particles from the runoff, BMPs are most effective for settling out fine sand and coarser material. <br /> Some examples of BMP sediment barriers include: <br /> • Sediment barriers (bales, silt fences, and earthen berms), and <br /> • Check structures. <br /> Hitch Rack Ranch Quarry Permit Application M-2016-010 <br /> September 26, 2016 G-20 <br />