The spatial distribution of metals in streambed sediment and surface water
of Silver Creek, McLeod Creek, Kimball Creek, Spring Creek, and part of the
Weber River, near Park City, Utah, was examined. From the mid-1800s through
the 1970s, this region was extensively mined for silver and lead ores. Although
some remediation has occurred, residual deposits of tailing wastes remain in
place along large sections of Silver Creek. These tailings are the most likely
source of metals to this system. Bed sediment samples were collected in 1998,
1999, and 2000 and analyzed using two extraction techniques: a total extraction
that completely dissolves all forms of metals in minerals and trace elements
associated with the sediment; and a weak-acid extraction that extracts the metals
and trace elements that are only weakly adsorbed onto the sediment surface.
This latter method is used to determine the more biologically relevant fraction
of metal complexed onto the sediment. Water samples were collected in March
and August 2000 and were analyzed for total and dissolved trace metals.
Concentrations of silver, cadmium, copper, lead, mercury, and zinc in the streambed sediment of Silver Creek greatly exceeded background concentrations. These metals also exceeded established aquatic life criteria at most sites. In the Weber River, downstream of the confluence with Silver Creek, concentrations of cadmium, lead, zinc, and total mercury in streambed sediment also exceeded aquatic life guidelines, however, concentrations of metals in streambed sediment of McLeod and Kimball Creeks were lower than Silver Creek. Water-column concentrations of zinc, total mercury, and methylmercury in Silver Creek were high relative to unimpacted sites, and exceeded water quality criteria for the protection of aquatic organisms. Qualitative measurements of the macroinvertebrate community in Silver Creek were compared to the spatial distribution of metals in streambed sediment. The data indicate that impairment related to metal concentration exists in Silver Creek.
This report is contained in the following file:
wri014213.pdf (1 mb)
The file is readable with Adobe Acrobat Reader. The reader is available for free download from Adobe Systems Incorporated.
Foreword
Abstract
Introduction
Purpose and scope
Description of study area
Land use
Selected stream sites
Methods of sample collection and analysis
Streambed sediment
Surface water
Aquatic macroinvertebrate communities
Trace-metal concentration in streambed sediment
Spatial distribution of streambed sediment concentrations
Relation between enrichment and source
Enrichment relative to aquatic life criteria
Trace-metal concentration in surface water
Dissolved and total metal concentrations
Loads of metals
Relation of water quality to toxicity limits
Isotopic analysis
Mercury concentration in streambed sediment and surface water
Total mercury and methylmercury
Health of aquatic macroinvertebrate communities
Summary
References cited
Appendix A
Appendix B
Appendix C
AccessibilityFOIAPrivacyPolicies and Notices | |