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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. (Pull wall may be removed at Owner's option) <br />5. Bacldill to the approximate original contours minus topsoil depth in uniform <br /> B" lifts. Baclcfill 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 MdcR plan. <br />7. Seed and mulch as called for by the MdcR plan. <br />8. Leave .all areas tree draining and provide erosion protection for seed on <br /> steep slopes as required by the MdcR plan. <br />E. r2eclamation 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 sees 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. ~ Pive (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 !or the failure surfaces through the Portal <br />,;i Bench Turnout. <br />TABLE 2 <br />Reclamation Alternatives for the Steep Slope Above the Portal Bench <br />Turnout with Corresponding Factors of Safety <br />Refer Dewatering Degree Upslope Minimum <br />Case to Exhibit System left of Retaining wall Factor of <br />Number Number Tn Place Compaction Left in place Safety <br />T 3 Proposed Road Cross Section 1.319 <br />8 4 No 85% 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 of the cut to become inoperable. Cases 10, 11 and 12 assume <br />aIl of the system is operable. <br />.` <br />~,. <br />