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The Consolidated Mutual Water Company <br />11/25/2013 <br />The computer model assumed a theoretical east -west cross section for the proposed quarry. The material was <br />assigned a hydraulic conductivity of 2.7E -06 cm /sec, the midrange combined value from the in -situ permeability <br />testing (Table II), to evaluate the maximum potential seepage loss. The model assumed three different <br />groundwater conditions; 25 ft above the proposed reservoir level, at the midpoint of the reservoir (25 ft below <br />the water surface), and 25 ft below the bottom of the reservoir floor (75 ft below the water surface). Seepage <br />results were considered in cubic ft per day per square foot of reservoir (ftl /day /ft2), the same measurements <br />.. considered by the Office of the State Engineer. Seepage for the first groundwater scenario reported inflow into <br />the reservoir, while the other two scenarios reported outflow from the reservoir. <br />The results of the flow into or out of the reservoir perimeter and bottom were generally small (± E -03 ft3 /day /ft-' <br />or smaller). An equivalent volume loss of up to about SO gallons per day can be considered for a 10 -foot wide <br />section through the middle section of the proposed central reservoir. These results of this assessment are <br />considered consistent with the use of a quarry pit as a water storage reservoir in Colorado. <br />From a geological perspective, water losses due to seepage are unlikely. The intruded basalt is surrounded by <br />relatively impermeable shale. Due to this geologic setting, the basalt will act as a "closed" local system and will <br />be isolated from the larger regional system. During initial filling of the reservoir, some losses should be <br />-� expected as the basalt becomes fully saturated. After saturation, the shale will act as an aquatard and the water <br />will be trapped in the basalt and the system will reach a steady -state where an insignificant amount of flow will <br />occur through the bedrock. Quantification of the initial loss during filling of the reservoir with the current <br />.., amount of data is not possible without making significant assumptions and extrapolations; however, we believe <br />that this initial loss will also be insignificant when compared to losses due to other mechanisms such as <br />evaporation. <br />Water level readings on borings and monitoring wells after drilling was complete showed artesian conditions in <br />two locations in the form of water exiting the top of casing or monitoring well. Artesian conditions occur when <br />the water pressure in the formation is greater than the pressure due to elevation head. The most common <br />reason for artesian conditions is a hydraulic connection between a formation and a source of water at a <br />significantly higher elevation with an impermeable layer acting as a hydraulic barrier or "cap" overlying the <br />formation. <br />Observations from the Brierley staff taking the water measurements noted that there was a pool of water in the <br />quarry where runoff collected which was located at a higher elevation than the two locations where artesian <br />conditions were observed. Brierley believes that this pool is the source of the artesian conditions observed. If <br />correct, the observed artesian conditions are additional evidence that the basalt plug is a "closed" system as the <br />water pressure has not significantly decreased since first noted after drilling. <br />BRIERLEY 13 <br />ASSOCIATES <br />Cre<uing Sih7Ce Undtr3roi�nit <br />