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<br />SUMMARY OF TASKS <br /> <br />The objective of the Rio Grande Reservoir Multi-Use Enlargement and Rehabilitation <br />Preliminary Design is to further investigate the technical issues associated with <br />enlargement and rehabilitation of the Reservoir. In particular, additional geotechnical <br />issues related to spillway crest elevation will be examined as well as issues related to <br />flood hydrology and spillway sizing. Wetland/permitting, hydrologic, and legal analysis <br />will be conducted along with an evaluation of operational and storage agreements and <br />public/stakeholder outreach. A detailed description of each task is provided below. Also <br />attached separately is a detailed cost estimate for the study. <br /> <br />Task 1 - Geotechnical Analysis <br /> <br />In order to enlarge the Reservoir, the potential for future landslide movement in the <br />Reservoir and left abutment requires further evaluation. Deere & Ault Consultants, Inc <br />will lead this task. They will be supported by Mr. Robert Kirkham, a renowned Colorado <br />geologist. Mr. Kirkham is based in Alamosa and completed the landslide mapping on Rio <br />Grande Reservoir in 1983 and also co-authored a paper on the West Lost Creek Slide that <br />occurred near the Reservoir in the 1990s. Deere & Ault will conduct the field work <br />necessary to map the Reservoir Basin and West Lost Creek Basin to compare geology <br />and determine if a slide of this type could occur in the near future under existing climatic <br />conditions in the Reservoir Basin. A slope stability analysis of the Reservoir will be <br />conducted using the GeoSlope computer package. In addition to the landslide analysis, a <br />hydraulic analysis of the required outlet improvements under existing and proposed (i.e., <br />enlarged) conditions will be conducted using Flow Master software. <br /> <br />Upon completion of the landslide and outlet hydraulic analyses, Deere & Ault will <br />prepare the following deliverables: <br />D Preliminary design drawings of the proposed improvements to the dam and spillway; <br />D Detailed engineering cost estimates for both rehabilitation and enlargement of the dam; <br />D A preliminary design repOli summarizing all of the finding. <br />The total cost for this task is $92,680. <br /> <br />Task 2 - Wetlands Analysis <br /> <br />In the initial wetlands analysis, Sugnet Environmental, Inc. (Sugnet) identified 1,264 <br />acres of jurisdictional wetlands and other waters of the U.S., including two potential <br />"fens" areas. In this study, Sugnet will conduct a wetlands delineation per the U.S. Army <br />Corps of Engineers (USACE) 1987 Wetland Delineation Manllal and procure written <br />verification of wetland delineation from USACE staff. This written verification from the <br />USACE ofSugnet's final wetlands delineation map will be suitable for Clean Water Act <br />Section 404 permitting purposes for five years. Sugnet will also produce a suggested <br />wetlands mitigation and monitoring plan for the impacted wetlands that will be necessary <br />as pati of future NEP A processes. In addition to the wetlands delineation, Sugnet will <br />conduct other investigations that will also be needed to address future NEP A <br />requirements. These investigations include a cultural resources assessment of the project <br /> <br />2 <br />