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2. Construction Alternative 1 - Repair with Riprap <br />This alternative considered the following action to repair and rehabilitate the damaged face of the <br />dam as follows; 1) Removing the existing riprap from the upstream face of the dam and stockpiling <br />the riprap for future use. 2) Borrowing soil from the reservoir bottom to flatten the existing slope <br />from a 2H: 1V to a 3H: 1V. 3) Grading the crest of the dam to a constant elevation of 5673 feet <br />and placing 4 inches of roadbase on the dam crest for erosion protection. 4) Installing 24 inches <br />riprap and 6 inches of bedding material on the flattened slope to prevent further erosion due to <br />wave action. 5) Adjust the height of the intake structure walls to allow for the flattening of the <br />slope. A depiction of the existing and proposed cross - sections of the Allen Lake dam is shown on <br />Figure 4. <br />The complete breakdown of the work proposed and the cost of the work proposed for Alternative 1 <br />for Allen Lake is shown in Table 3. <br />TABLE 3 <br />ALLEN LAKE REHABILITATION <br />ALTERNATIVE 1 - REPAIR WITH RIPRAP <br />ITEM <br />DESCRIPTION <br />QUANTITY <br />UNITS <br />UNIT <br />PRICE <br />AMOUNT <br />1 <br />Insurance, Bonds <br />1 <br />L.S. <br />$ 7,800.00 <br />$ 7,800 <br />2 <br />Mobilization, Demobilization <br />1 <br />L.S. <br />$ 15,500.00 <br />$ 15,500 <br />3 <br />Surveying Construction Staking <br />1 <br />Each <br />$ 3,500.00 <br />$ 3,500 <br />4 <br />Dewatering /Erosion Control <br />10 <br />Days <br />$ 500.00 <br />$ 5,000 <br />5 <br />Earthwork <br />Stripping <br />1 <br />L.S. <br />$ 2,000.00 <br />$ 2,000 <br />Borrow <br />10800 <br />C.Y. <br />$ 3.00 <br />$ 32,400 <br />Fill <br />10000 <br />C.Y. <br />$ 4.00 <br />$ 40,000 <br />6 <br />Staff Gage <br />1 <br />L.S. <br />$ 5,000.00 <br />$ 5,000 <br />7 <br />Inlet Stucture Walls <br />18 <br />C.Y. <br />$ 625.00 <br />$ 11,300 <br />8 <br />Remove & Stockpile & Place Existing Riprap <br />3000 <br />Tons <br />$ 15.00 <br />$ 45,000 <br />9 <br />Furnish & Place Imported Riprap <br />5000 <br />Tons <br />$ 34.00 <br />$ 170,000 <br />10 <br />Furnish & Place Imported Riprap Bedding <br />1875 <br />1 Tons <br />1 $ 32.00 <br />$ 60,000 <br />11 <br />Furnish & Place Class 5 Roadbase <br />400 <br />Tons <br />$ 26.001 <br />$ 10,400 <br />12 <br />Place Topsoil & Seeding <br />1 <br />Acres <br />1 $ 2,500.001 <br />$ 2,500 <br />TOTAL CONSTRUCTION COST $ 411,000 <br />CONTTNGENCY(20 %) $ 83,000 <br />ENGINEERING /LEGAUSURVEYING $ 83,000 <br />TOTAL 1 $ 577,000 <br />Allen Lake and Lake Isabelle — 12.012 <br />Left Hand Ditch Company Page 11 <br />