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<br />Y4 <br /> <br />Exhibit A <br />Grant for Proposed Feasibility Study of Long Hollow Reservoir and Red Mesa Reservoir Enlargement <br /> <br />. <br /> <br />. <br /> <br />~ <br /> <br />,..j <br /> <br />Subsurface Exploration Program & Exploration Observation <br /> <br />Feasibility level plans, designs, geotechnical analysis, yield analysis, cost estimates, and <br />general construction schedule will be prepared in this phase. The CWCB criteria for <br />feasibility level plans will be used to conduct the engineering analysis. <br /> <br />A subsurface exploration program will be conducted to define the subsurface profile, <br />obtain samples for laboratory testing and estimate the groundwater level at the axis of the <br />dam, the proposed spillway alignment, and borrow areas within the reservoir. <br /> <br />The subsurface exploration program will be conducted using test borings and test pits. <br />Drilling will be conducted to obtain relatively undisturbed soil samples using standard <br />penetration tests and rock coring. Test pits will be utilized in borrow areas to obtain bulk <br />samples. . <br /> <br />Three test borings will be drilled along the alignment ofthe proposed dam. One hole will <br />be drilled at each abutment to a depth of approximately 150 feet and one hole will be <br />drilled near the streambed to a depth of approximately 80 feet. These holes will be <br />drilled to determine the strength, permeability and compressibility of the materials <br />directly below the proposed embankment. Soil penetration tests will be taken every 5 <br />feet in the overburden soils and the rock beneath the site will be cored continuously to the <br />maximum hole depth. Packer tests will be conducted at 5 locations in the abutment holes <br />and 2 locations in the foundation hole to evaluate in situ permeability. A 2-inch plastic <br />pipe piezometer will be placed in each of the holes. The piezometer will be slotted at <br />appropriate depths based upon the conditions encountered and a protective cover will be <br />installed at the ground surface for subsequent water level readings. <br /> <br />Subsurface conditions in the valley bottom within the reservoir will be explored to <br />evaluate the suitability of this area as a borrow site and the ability of the reservoir to <br />retain water. Four test borings to a depth of 50 feet and 3 test pits to a depth of <br />approximately 15 feet are anticipated for this part of the study. Three additional test pits <br />will be required on the valley sides in the reservoir or above the proposed water surface <br />elevation to explore for suitable riprap and/or concrete aggregate. <br /> <br />Alternative spillway configurations on the right abutment will be evaluated by drilling <br />three 50-foot deep test holes to investigate the subsurface profile. Slotted PVC <br />monitoring wells with protective covers will be installed in the all test holes. <br /> <br />Specifications for subsurface investigations were prepared by and a proposal was <br />obtained from Western Engineers in Grand Junction to provide the equipment and <br />materials necessary to conduct the subsurface investigations, including access to the <br />location oftest pits and test borings. <br /> <br />Laboratory Testing Program <br /> <br />A laboratory testing program will be conducted to evaluate the shear strength, <br />compressibility classification and permeability of the soils and bedrock encountered at <br />the site. Direct shear strength 1esting will be conducted for two embankment soil types. <br />Each shear strength envelope will be developed by conducting three drained direct shear <br />tests at different normal loads. The testing program will include a set of two time <br /> <br />:',j <br />