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<br />. <br /> <br />to loosen sediment material, pump it into a discharge line and transport the dredged <br />slurry to a sedimentation basin where it can be settled and decanted. The disposal site <br />must be sufficiently flat and large enough to allow for local permanent disposal of the <br />dewatered sediment. <br />e. Hydro-Suction - This option is similar in concept to mechanical dredging except <br />that the removal of the sediment from the reservoir basin is done with out a pump. The <br />sediment is lifted from the bottom of the reservoir and transported downstream from the <br />dam based on the difference in elevation between the reservoir level and the downstream <br />disposal site. Both mechanical dredging and hydro-suction require a disposal site and, <br />therefore, the Phase One work will include identification of potential sites. <br />f. Reduction of Basin Sediment Yield - Although experience has shown that <br />catchment management is not generally an economically feasible approach to reservoir <br />sedimentation management, information from long-time local residents suggests that a <br />large source, if not the primary source, of sediment consists of a landslide, or series of <br />landslides, located within a very limited stretch of one of the tributaries to Paonia <br />Reservoir. This part of the study will include a detailed field examination of the <br />drainage basin, selected sampling and testing of grab samples from any suspect source <br />areas, review of aerial photography, research existing sediment yield information <br />(including regional data), identification of both human and natural disturbances and <br />characterization of any channel degradation. <br /> <br />5. The evaluation of alternatives will include conceptual designs as appropriate and <br />associated cost estimates. <br /> <br />. 6. Investigate Regulatory Constraints - The cost and/or feasibility of some mitigation <br />options may be significantly impacted by the necessity to satisfy federal, state and local <br />legislative and regulatory agency rules and standards. Additionally, some of the methods <br />normally used for sediment control may not be commonly used in the State of Colorado and <br />rules and regulations may need to be clarified, expanded or revised to address these methods. <br />Therefore, it will be important to adequately identify and define the limitations that will <br />constrain these methods. <br /> <br />7. The Phase One study findings will be presented in a report. The report will identify the <br />technical feasibility of the alternative sediment management techniques and will select the most <br />economical sediment management options. Additionally, the report will provide the engineers' <br />opinions regarding the likely degree of success that can be anticipated using the techniques <br />evaluated. The report will be followed by discussions between the project sponsors and the <br />engineers. The objective of the discussions will be to agree on two or three selected sediment <br />management techniques that should be investigated in more detail in Phase Two. <br /> <br />. <br /> <br />Phase Two work will consist of refining the selected option( s) by obtaining more comprehensive <br />supporting data, performing more detailed engineering analyses, refining cost estimates and <br />pursuing needed permits. The actual scope of the Phase Two work will be somewhat dependent <br />on the results of the Phase One analyses. The current application for funding is based on the <br />anticipated scope of work described below. The cost estimate includes a not-to-exceed amount <br />for investigation of the selected option(s). A contingency factor has been applied to the <br />estimated study cost to account for any needed modifications to the Phase Two scope of work: <br /> <br />1. Detailed Evaluation of the Selected Option( s) - Depending on the selected option( s) the <br />3 <br />