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Long Hollow Reservoir <br />Feasibility Study <br />for removal of cuttings consisted of an air/foam mixture. Three drill holes were drilled along the <br />proposed dam axis: <br />1. Drill hole No. 1 was drilled on the right abutment. Except for 3 feet of surficial residual <br />soil, the profile was found to be completely in the Cliff House Formation, consisting <br />mainly of alternating layers of relatively thin sandstone, shale, and mudstone. Some <br />sandstone layers ranging up to 6 feet thick were encountered. Within the Cliff House <br />Formation, there are numerous indications of depositional flowage and mixing with very <br />irregular bedding, muddy conglomerates/breccias, and inclusions of sandstone and <br />mudstone fragments. Between the depths of 15 feet and 40 feet, white fillings of soluble <br />salts (probably gypsum) were visible in joints and bedding planes. The concentration of <br />this material appeared to be greatest toward the middle of this zone. There were also <br />some indications that some of these fillings had been partially removed, leaving small <br />voids. In the shallower zones, there are numerous indications of historic water flow in <br />the form of limonite and iron staining. The water table in this hole was encountered at <br />the 34-foot depth. The surface elevation of the drill hole was not measured, but it appears <br />that the ground water level is slightly higher than the stream elevation, indicating that the <br />groundwater is tributary to the stream. Return of the air-foam circulation medium was <br />100 percent lost at about the 16-foot depth. As drilling continued, a small percentage of <br />circulation was recovered (estimated at less than 10 percent), likely due to partial <br />plugging of the permeable zones. Pressurized packer tests were performed throughout the <br />depth of the hole with a packer interval of 23 feet in order to determine the formation <br />permeability. Following are the results of the tests: <br />Depth (Feet) Permeability Coefficient (Feet/Year) <br />12.5 to 35.5 1,658 <br />22.5 to 45.5 992 <br />40.5 to 63.5 12 <br />991-077.120 Wright Water Engineers, Inc. Page 23 <br />April 2005 <br />