ENVIRONMENTAL IMPACT OF HISTORICAL MINING IN THE OQUIRRH MOUNTAINS, UTAH

Across the western United States there has been a history of heavy metal contamination and acid mine drainage from tailing piles from areas with historic mining activity. Specifically, in central northern Utah, the Oquirrh mountains included mining districts which incorporated historic Ophir, Stockton, and Mercur mines, which operated intermittently from 1870 to 1971. These mining districts targeted lead, zinc, copper, silver, and gold deposits. Many present day communities are located downstream of these mine-waste contaminated streams and rivers and therefore face serious health problems, including various types of heavy metal poisoning. The goal of this project was to determine the levels of heavy metal contamination in creeks down slope from known historic mines in the Oquirrh Mountain mining district that were likely to have acid mine drainage and the impact on those drainage systems. Water, vegetation, and soil samples were gathered in drainages near Ophir, Stockton, and Mercur historic mining districts. We measured the concentrations of various heavy metals on both an inductively coupled plasma - optically emission spectrometer (ICP-OES) and mass spectrometer (ICP-MS). In situ water characteristics were analyzed with a probe that measured pH, total dissolved solids, oxidation and reduction potential, and temperature to characterize water thermodynamics. With the summarized dissolved mineral and elemental data from ICP-OES/ICP-MS we are able to see the amounts of heavy metal concentrations, including high levels of antimony, arsenic, and led in each sample and correlate them to specific tailings piles in the upper reaches of the watersheds.