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<br />equipment (at a cost of $2.00 per cubic yard), that 30 percent would require ripping with a single <br />tooth dozer (at a cost of $3.00 per cubic yard), and that no blasting would be required. The cost of <br />this type of excavation alone would be approximately $2.30 per cubic yard leaving at most $1.05 <br />to $1.60 per cubic yard for placement of compacted fill in the berm, hauling the excess material to <br />waste and any other earthwork expenses. Ifblasting is required (at a typical cost in excess of $8.00 <br />per cubic yard) the excavation costs could increase tremendously beyond those estimated above. <br />Therefore, we believe that widening the existing spillway would be at least as costly as the Plan C <br />alternatives and could potentially be much more expensive. We believe that the social and financial <br />aspects of this alternative are each sufficient to make it infeasible and when combined are sufficient <br />to make this alternative not worthy of further consideration. <br /> <br />C. Plan C - Constructing a New Spillway <br />C.l General <br /> <br />For the following reasons, the best location for a new spillway is over the north dam of the <br /> <br />reservOIr. <br /> <br />. It can be located entirely on Company property, <br />. It is as far removed as possible from the residential subdivision, <br />. It is located as far back from the main road as possible, <br />. It is somewhat screened by trees, and <br />. It is located in the natural drainage where flood flows would proceed if there were no dam. <br /> <br />The new spillway can be built of formed concrete or roller compacted concrete. To reduce <br />the spillway crest width, and minimize the cost of the structure, the head on the spillway should be <br />maximized. This can be accomplished by raising the dams through the placement of additional fill, <br />construction of a parapet wall, or a combination of both. The spillway width can be minimized by <br />utilizing a fuse plug constructed on the concrete spillway floor. The lower the spillway floor <br />elevation the greater the head available and the narrower the required crest width. <br /> <br />The following three subsections of this report describe three options available when <br /> <br />considering the construction of a new spillway: I) the construction material, 2) the effect of raising <br /> <br />the dams (and therefore the maximum flood storage level) on the spillway width required, and 3) <br /> <br />the possible inclusion of a fuse plug in the new spillway. <br /> <br />27 <br /> <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />