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Hydro Investigation Results <br /> Santa Fe Formation-West Pit Battle Mountain Resources Inc. <br /> unit of the Santa Fe Fm. The newly installed well,WP-6, encountered the Santa Fe Fm from 55 to <br /> 90 feet below ground surface (ft bgs). The Santa Fe Fm in WP-6 is described as interbedded <br /> sandstone,claystone and siltstone that was highly weathered near the top,becoming less weathered <br /> and more competent with depth. The borehole log for WP-6 is included in Attachment A — <br /> Borehole Logs and Well Construction Diagrams. Figure 2 is a cross-section that shows the general <br /> lithologic character and hydrostratigraphic units that are penetrated by each well and the depths of <br /> screen placement. Attachment A—Borehole Logs and Well Construction Diagrams also includes <br /> borehole logs and well construction diagrams for the observational wells. Additionally, Table 1 <br /> summarizes well construction information for the pumping and observations wells. <br /> 2.1 Well Installation/Completion <br /> Well WP-6 was installed along the southeast boundary of the West Pit within the alluvial window <br /> in October 2022. Originally,WP-6 was intended to go to a total depth of 130 ft bgs but the shallow <br /> bedrock meant WP-6 was drilled to a total depth of 90 ft bgs. The alluvium/Santa Fe contact was <br /> encountered at a depth of 55 ft bgs. The Santa Fe/Precambrian Gneiss contact was intercepted at a <br /> depth of 90 ft bgs. The well was plugged back to a depth of 88.83 ft bgs and screened within the <br /> Santa Fe Fm from 62.83 to 88.83 ft bgs. <br /> Well WP-6 was constructed in compliance with Colorado State Engineers Office requirements. A <br /> well construction diagram is provided in Attachment A— Borehole Logs and Well Construction <br /> Diagrams.WP-6 is completed with six-inch diameter PVC casing and screen. The well is screened <br /> across the Santa Fe Fm. The well screen is 20-slot. Screen length in the well is 26 feet. A sand <br /> pack, using 10/20 silica sand, was placed in the well annulus to a depth of two feet above the top <br /> of the screen. A bentonite seal, using bentonite chips, was placed above the sand pack. Cement <br /> grout was placed in the well annulus from the top of the bentonite seal to ground surface. The well <br /> is fitted with a locking steel protective cover. <br /> The well was developed using a combination of bailing and surging. The well was alternately <br /> bailed and surged over a two-day period, until the bailed water was relatively sediment free. <br /> The top of casing for WP-6 will be surveyed and tied back to the common datum used for other <br /> site monitoring wells. Water level measurements from the wells will be used to develop <br /> potentiometric surface maps for further evaluation of hydraulic gradient, groundwater flow <br /> direction,velocity, and discharge. <br /> 2.2 Hydrologic Test Results <br /> Prior to beginning the pumping test, depth to water was measured at the pumping well and each <br /> observation well using a water level meter. The initial depth to water measurements,total depth of <br /> the wells, and saturated thickness are reported in Table 2. The field measured distance between <br /> wells is indicated on Table 3. The average saturated thickness for the alluvial aquifer observation <br /> wells was approximately 30.5 feet(Table 2). The average saturated thickness feet for the Santa Fe <br /> Fm aquifer was approximately 30 feet(Table 2). <br /> February 2023 3 Engineering Analytics,Inc. <br />