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1. Inspect and ensure that the dewatering system is operating properly. Check <br />and take necessary measures to protect all in place piezometers. <br />2. Carefully remove and dispose of the concrete structures protecting the <br />outlet of the horizontal drains. <br />' 3. Remove and salvage the downslope retaining walls. <br />4. Remove the top portion of the upslope retaining wall below the proposed top <br />soil depth. (Full wall may be removed at Owner's option) <br />5. Backfill to the approximate original contours minus topsoil depth in uniform <br />8" lifts.. Backfill shall be compacted to at least 85% of maximum standard <br />proctor density. <br />6. Spread topsoil to an even depth of 12" to 18" as called for by the MbcR plan. <br />t 7. Seed and mulch as called for by the MdcR plan. <br />8. Leave all areas free draining and provide erosion protection for seed on <br />steep slopes as required by the MdtR plan. <br />' E. Reclamation Alternatives -Cross Section at and above the Portal Bench Turnout - <br />Access Road Station 65+00: <br />' The portal bench turnout is within the landslide area and, as such, a dewatering <br />system has been designated for this area. The portal turnout is characterized by a <br />large cut and a steep slope above the cut. Exhibit 3 illustrates the results of the <br />stability analyses conducted for the proposed road geometry with the dewatering <br />system in operation. Five (5) possible alternativees were analyzed for the <br />reclamation of this cross section and these are summarized in Tables 2 and 3 below. <br />Table 2 summarizes the analyses for the steep slope above the Portal Turnout, <br />while Table 3 summarizes the analyses for the failure surfaces through the Portal <br />Bench Turnout. <br /> TABLE 2 <br /> <br /> Reclamation Alternatives for the Steep Slope Above the Portal Bench <br />' Turnout with Corresponding Factors of Safety <br />' Refer Dewatering Degree Upslope <br />Case to Exhibit System left of Retaining wall Minimum <br />Factor of <br /> Number Number !n Place Compaction Left in place Safety <br /> <br /> <br /> 7 3 Proposed Road Cross Section 1.319 <br /> 8 4 No S5% No .818 <br /> 9 5 See note 85% No .876 <br />' 10 6 Yes 85% No 1.319 <br /> 11 6 Yes 95% No 1.319 <br />' 12 6 Yes 85% Yes 1.319 <br /> Note: Case 9 retained the dewatering system down slope from the cut, but allowed the <br /> dewatering system upslope oP the cut to become inoperable. Cases 10, it and 12 assume <br /> all of the system is operable. <br /> <br /> 7 <br />' <br />