Page 81 - Geologic Investigations in the Lake Valley Area, Sierra County, New Mexico

enrichments of Pb approaching 20,000 ppm also occur in dumps with high GSTE scores, but these dumps also have relatively abundant carbonate and depleted sulfide presence and, hence, low potential for acid water mobilization of the Pb. The elements with the greatest enrichments above their significant baseline concentrations, notably Pb, Sb, and Zn, also have low solubility fractions of their bulk solid concentrations relative to other elements that will lessen release into the environment. Conversely, Mn, Mo, and to a lesser extent As, have much
Note: A combined list of references for all chapters of this Professional Paper is located at the end of this volume, begin ning on page 76.
greater solubility fractions and will solubilize proportionally more of their bulk concentrations from the mine dump solids.
In conclusion, the approach used in this report—combining bulk composition as a GSTE score of the solid material from mine dumps—easily screens for enrichment of various GSTE. Combining the GSTE score with solubility and acid-generation mineral abundance data subsequently identifies those dumps most likely to release GSTE into the environment and identifies the specific GSTE likely to be released.
Geochemistry of Mine Dump Material from the Lake Valley Mining District 75