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4) Replace the upstream outlet gates and repair the outlet conduits <br />Analvsis of Alternatives <br />A/te~native No. 1- Do Nothing <br />One course of action considered was the Do Nothing Alternative. This alternative suggests performing <br />no repair work on either the outlet gates or the outlet conduits. No construction costs will be involved. <br />Given this alternative FRICO would continue to operate using the existing facilities. As both the gates and <br />outlet conduits have reached their useful life it is expected that in the near future the gates and/or the <br />outlet conduit will fail. Failure of the upstream gates would mean that FRICO would have to depend <br />solely on the downstream guard gates for safety and operations. This would create a potentially unsafe <br />condition; FRICO would then be forced to draindown the reservoir under emergency conditions and <br />replace the upstream gates. Failure of the outlet conduits could allow water from within the conduits to <br />exit into the adjoining soil, creating the potential for erosion of dam embankment material, known as <br />piping. Piping could result in sink holes developing in the dam or ultimate, if unattended, failure of the <br />dam. FRICO would therefore be forced to drain the reservoir in an emergency condition if the outlet <br />conduits were allowed to fail. <br />Failure of either the upstream gates or the outlet conduits would result in an emergency draining of the <br />lake, causing FRICO significant monetary losses, and could potentially lead to dam safety related issues. <br />A/ternative No. 2- Rep/ace the Upstream Out/et Gates On/y <br />The second alternative explored was to replace the upstream outlet gates while leaving the outlet <br />conduits in their current condition. In this alternative the reservoir would be drained down to facilitate <br />construction at the gates. The existing gates and operators would be removed. Two new slide gates <br />would be installed. The installation requires a connection to the outlet conduits, so the upstream most <br />segments of the existing conduits would be removed and replaced as part of the installation. This work <br />would include replacing the segment of conduit where the leak currently exists through the existing <br />fitting. New hydraulic operators would be installed along the upstream face of the dam. Operators would <br />10 <br />