Browsing Indiana State University Electronic Theses and Dissertations by Subject "Acid mine drainage."
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Assessing Environmental Conditions at the Friar Tuck Mining Complex, Dugger, IndianaMany abandoned mine lands (AML) continue to present significant environmental concerns. The abandoned Friar Tuck Mining Complex in Greene and Sullivan counties, Indiana, continues to impair local water quality despite closing in 1952 for operations and multiple remediation attempts. Most areas within the Friar Tuck Mining Complex have been successfully remediated; however, the area of research interest requires additional treatment and continues to be impacted by runoff from gob piles. Subsequently, areas characterized by a loss of vegetation where mine seeps occur behave unpredictably and are characterized by the exposure of bare soil. These mine seep areas are of particular concern because contaminated soil may leave the site during summer months as aerosols due to soil desiccation. The primary goal of this project was to evaluate spatial variability in the distribution of metals in surface soils. In May 2010, 258 soil samples were collected at the Friar Tuck Mining Complex to evaluate metal accumulation and bioavailability using several different geochemical techniques, including bulk geochemistry following reaction with water and acid and a sequential extraction technique. Results indicate that surface soils at the Friar Tuck Mining Complex continue to be degraded, pH is moderately to highly acid (pH=4-1) in areas of mine seeps, surface flow, and where the slurry pond narrows and begins to discharge into Mud creek. Surface soils also have elevated concentrations of bioavailable metals due to the persistent influence of AMD, such as Zn, Cu, Cr and Pb, especially in areas of mine seeps, surface flow, and water ponding.
Environmental Conditions of Green Valley LakeGreen Valley Lake, western Indiana, has experienced periodic inputs of acid mine drainage (AMD) from the abandoned Green Valley Coal Mine. The lake serves as a state fishing area, and AMD inputs may affect the aquatic ecosystem and human health. The purpose of this research is to determine to what extent the sediments in Green Valley Lake are acting as sinks for metals and if they may impact water quality. Water and bottom sediment samples were taken throughout the lake to evaluate spatial variability of contamination and to determine how the metal concentrations compared to Post Archean Average Shale (PAAS) background values and sediment quality guidelines (SQGs) values. Three cores were taken from the Northwest portion of the lake, where AMD enters via surface flow to evaluate temporal changes in contamination. Results indicate that water quality at Green Valley is acceptable, pH is slightly acidic (pH=6.4) near the locations of AMD input and increases to the east (pH=8.30). The northwest portion of Green Valley Lake is an eutrophic lake, based on its nutrient levels and Secchi disk measurements. Organic matter content, based on LOI, is higher in the older portion of the lake (7-33 wt %) due to the influence of vegetation surrounding the lake. Bottom sediment at Green Valley Lake are acting as a sink for metals and nutrients. Ni and Cd concentrations are above the sediment quality guidelines severe effect level, while Zn and Pb were above the probable effect level. Metals over the severe and probably effect levels should continue to be monitored in the sediments at Green Valley Lake to ensure that organisms are not being impacted.