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present and constantly managing the same approximate rate of underground flow (~1 gpm) year-round. If the toe seeps were to be hydrologically linked to the sump, it stands to reason that the seeps would also flow year-round. However, the seeps are seasonal. They have only been recently located and studied. The seeps aze currently dry, yet the underground sump is not. The flows within the seeps have been observed to be directly correlated to the flow conditions within Deadman Gulch. Further study of the Deadman Gulch water chemistry indicated that the low-pH conditions persist over the length of the drainage. This maybe due to several factors including; the natural neutralization processes either aze saturated or never existed, andlor the hydrogeology may lend (add) to the acidity. It is possible that the neutralizing potential of the Gulch is never tapped since there is little retention time between the water and channel itself. In addition, any acidity leant by pyrite oxidation from the waste rock pile would be unstable because it is balanced rapidly with oxygen and water. Therefore, it appeazs that the hydrologeologic setting of Deadman gulch is lending to the continuous, and relatively stable nature of the low pH. In addition, comparison of the Deadman Gulch setting to other settings in close proximity (e.g. the Slumgullion slide, and the hydrothermally altered azeas within the Uncompahgre Caldera that occur adjacent to the Lake Fork of the Gunnison) indicate that the area commonly has naturally acidic conditions (Neubert, J.T., 2000). For instance, the Slumgullion Slide contains fine- grained, clay-rich minerals with a compositional analysis indicating sulfates as the most abundant soluble salts, thereby lending to a natural acidic chazacter (Chleborad, A.F. et al., 1996). Colorado Geologic Survey studies of the Slide yielded naturally acidic conditions with manganese, iron and aluminum exceedences of state standards in all samples collected within the slide azea. Similazly, the CGS evaluated natural, hydrothermally altered settings that occur adjacent to the Lake Fork of the Gunnison and create slightly lower pHs within the Lake Fork (6.98 at the confluence) (Neubert, J.T., 2000). From a toxicological standpoint the prevalent low pH within Deadman Gulch is not concerning. Low pH by itself is not necessarily toxic. Many organisms are adapted to pH extremes which is best exemplified by the fact that there is abundant vegetation directly within the Deadman Gulch channel. The secondary effects of low pH, such as toxic metals mobilization, are the true concern from a toxicological standpoint. Review of the Deadman Gulch data indicates that metals precipitate or plate onto solid surfaces or suspended materials over the course of the drainage length. The ultimate load to the Lake Fork is considerably less than the initial `dose' from the waste rock toe seeps. Sample analysis from within the Lake Fork did not yield any detected concentrations of metals above criteria limits protective of aquatic life. Recommendations The results of this study indicate that the Deadman Gulch base flows (background flows) are chemically and hydrologically linked to the waste rock toe seeps observed at the base of the Golden Wonder Leve16 pad (and cited by CDPHE as point source discharges). The resulting water quality contains acidic pHs that have caused concern to others. Review of the Deadman Gulch site setting indicates that this intermittent tributary is not affecting water quality within the receiving drainage of the Lake Fork of the Gunnison and contains chemical chazacteristics typical to the azea. GGI recommends that Deadman Gulch base flows be routed away from the waste rock pile, however GGI wntends that there aze no negative impact and that the Gulch should beheld to suitable expectations and standards. Page 12 of 16