Lead and zinc tailings are common in the Ozark region of Missouri and constitute an environmental hazard, particularly to soil and water resources. This study investigated the elemental release patterns of low-level. Pb-Zn dolomitic waste-rock along Bee Fork Creek in Reynolds County, Missouri, to determine whether these tailings are releasing sufficient metal concentrations to adversely impact water and adjacent riparian resources. Aqua-regia digestion of control and impacted sites confirm the presence of substantial concentrations of As, Cd, Pb, Zn and other metals. Hot water and 0.01 M NaNO3 extractions recovered small portions of the total elemental pool and that only a very small portion of the total metal pool is labile. The EDTA extraction recovered greater concentrations of Ca, Mg, Pb, Zn and Cd than the hot water extraction. The Ca and Mg concentrations recovered by the EDTA extraction suggest partial dissolution of the dolomitic waste rock, thus promoting metal release. The EDTA Pb, Zn and Cd concentrations reflect recovery of these metals from the organic, exchangeable and waste rock fractions. Long-term weathering of the dolomite waste rock may promote the continuous, but low level, release of metals to Ozark streams.

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