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Lyons Quarry �` <br /> 112d Reclamation Permit Operations <br /> Technical Revision7 <br /> Item 7.0—Ground Control <br /> After the Fountain Formation sandstone at the crest of the highwall has been excavated, the dacite <br /> highwall in Quarry 1 (northeast facing) as well as the dacite highwall between Quarry 1 and Quarry 2 <br /> (northwest facing), will be scaled to remove any loose rock that accumulated on the highwall <br /> naturally or is deposited during excavation of the Fountain Formation. Attachment B —Grading Pan, <br /> Sheet 01 C-03, Details C, D and E show the proposed final configuration of the dacite highwalls <br /> along the northwest and northeast faces of Quarry 1. Ground Control work will be performed <br /> according to Technical Specifications Section 31 72 16 included in Attachment G. This work <br /> includes: <br /> • Rock slope scaling: The work consists of removing loose rock and debris in areas shown on the <br /> plans prior to placement of Rock Reinforcement(Number 10) or as directed by the Engineer. <br /> • Rock bolt installation: This Work consists of furnishing and installing Rock Reinforcement <br /> (Number 10) as shown in the Plans. <br /> Submittals for the Ground Control will include a qualifications statement, Scaling Work Plan, <br /> Construction Materials submittals, Rock Reinforcement Shop Drawings, a narrative of the testing <br /> procedures and application of anchoring materials, and drilling forms. <br /> The crew performing Rock Scaling shall remove or stabilize loose, hanging, or potentially dangerous <br /> or unstable rocks and soil debris on rock cut slopes using manual scaling techniques. The crew shall <br /> scale by hand methods using a standard steel mine-scaling rod or similar device, or by mechanical <br /> tools that can be hand operated (i.e. jack hammers). In addition to hand scaling techniques other <br /> measures such as hydraulic wedges, air pillow, or other mechanical means may be used if <br /> demonstrated to be effective and approved in writing by the Engineer. <br /> Rock Reinforcement may be needed for stabilization where large blocks are evident in the bedrock. <br /> Locations for Rock Reinforcement will be determined by on-site engineer after scaling operations are <br /> complete. Based on these field observations, the Engineer may increase, reduce, delete, or <br /> otherwise alter the Rock Reinforcement as necessary to address actual field conditions. For the <br /> costs estimated on the Ground Control task, the most conservative unit rates from the CDOT 2018 <br /> US Hwy 24 Rockfall Mitigation project were used (CDOT, 2018). For Lyons Quarry it is assumed that <br /> up to 144 hours of rock scaling will be required at a cost of$500 per hour due to the complexity of <br /> the highwall configuration. An assumed 20 rock bolts each with a drilled length of 30 feet will be <br /> needed for reclamation at a cost of$7,000 per bolt location. <br /> Item 9.0—Restoration -Test Plots, Soil Conditioning and Revegetation <br /> Reclamation areas will be restored depending on their proximity to the current channel alignment <br /> and whether backfill material is required as shown on Exhibit F- Reclamation Plan Map, Attachment <br /> C. <br /> 9.1 —Test Plots <br /> The final reclamation topsoil/growth medium, seeding, fertilization, and revegetation will be <br /> determined based on the results of Test Plots developed during the Quarry reclamation work using <br /> the soil types and slopes planned for reclamation to assist in determining the appropriate types and <br /> methods for reclamation. <br /> March 2021 1 18 <br />