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r <br />t; <br />Chemical Trace Evaluation for the Golden Wonder Mine Site <br />Prepazed By: Gault Group Inc./Cortez, CO <br />Prepazed For: Au Mining/Lake City, CO <br />Executive Summary <br />A `Chemical Trace' study was completed for the hydrologic system within the Golden Wonder <br />Mine Site. The purpose of the study was to determine the chemical characterization of all the <br />potential sources of water within and azound the site in order to construct connective flow <br />pathways based upon any observed common chemical chazacteristics. Omnipresent regulatory <br />interest has been drawn towazds the concern that the underground workings within the mine may <br />be causing seeps of daylighted water at the toe of the waste rock dump for the Level 6 workings. <br />However, further examination of the site setting yields the fact that there aze multiple possible <br />water sources linked to these seeps. Base flows from the immediately adjacent intermittent <br />drainage (Deadman gulch) occur within the historic Gulch channel which now resides <br />underneath the waste rock pile. In addition, a third, potential source of water may come as a <br />result of captured stormwater from the Level b pad which may eventually percolate into the <br />waste rock pile and emerge as toe seep flows. Thus, there aze three potential `sources' of water <br />associated with the seeps as shown using a conceptual diagram within Figure I. <br />This study served to chazacterize all three water sources in order to compaze the chemical <br />composition to the seep water quality. Any common chemical trends between the sample results <br />would help determine the actual source of the seeps. Additional information was obtained with <br />the analysis of solid material associated with the mine that was analyzed to test the leachate <br />chemical characteristic. Samples from the ore body, alluvial cap material, waste rock from the <br />Leve16 pad and solids collected from the stormwater sump were all analyzed for leachate <br />chemical chazacterization. <br />Results were presented using a variety of graphic techniques common to water typing (Piper <br />diagrams, Stiff, pie charts, etc.). Results indicate that the water quality chazacteristics of the <br />waste rock toe seeps (WRT-A and WRT-B) aze closely associated to Deadman Gulch <br />background water chemistry conditions. The analysis results of the seeps aze comparable to both <br />background locations (DM-BKG and SEEP (BKG)) as opposed to the undergound sump <br />location (SUMP) which contains significantly higher concentrations of all analvtes tested (Ca, <br />Fe, Mg, K, Si, Na, Si etc.). Measured concentrations of all anions and cations aze within the <br />same range as the background, vs. the sump results which are consistently higher by a significant <br />mazgin. Therefore, the resulting water chemistry of the seeps is likely a combination of both the <br />background water chemistry and the elutriate chemistry of all the solids analyzed. <br />Introduction <br />The Golden Wonder mine site is an historic mine site that has undergone several eras of mining <br />activity. The historic activities (1880's) included the development of the Leve16 portal and <br />associated pad wmprised of waste rock and alluvial materials from the slope. As mining <br />progressed, the waste rock pile encroached upon and eventually covered the adjacent intermittent <br />channel of Deadman Gulch. <br />Page 7 of 16 <br />