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Updated: May 26, 2026
10:44
Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies
Published on: July 1, 2016
Selected trace elements in the Sacramento River, California: occurrence and distribution
H E Taylor1, R C Antweiler, D A Roth
1United States Geological Survey, Boulder, CO 80303, USA. hetaylor@usgs.gov
Archives of Environmental Contamination and Toxicology
|December 24, 2011
Summary
Trace elements from Iron Mountain Superfund site impact the Sacramento River. Most metals remain dissolved or attached to colloids, traveling downstream rather than settling out.
Area of Science:
- Environmental Science
- Geochemistry
- Analytical Chemistry
Background:
- The Iron Mountain Superfund site is a source of trace element contamination.
- Acid mine drainage impacts water quality in the Sacramento River and its tributaries.
Purpose of the Study:
- To examine the impact of trace elements from the Iron Mountain Superfund site on the Sacramento River.
- To determine the concentration and distribution of various trace elements in dissolved and colloidal forms.
Main Methods:
- Utilized ultraclean sampling techniques at multiple sites along the Sacramento River and tributaries.
- Employed inductively coupled plasma-mass spectrometry and inductively coupled plasma-atomic emission spectrometry for trace element analysis.
- Analyzed both dissolved (ultrafiltered) and colloidal fractions of water samples.
Main Results:
- Measured concentrations of numerous trace elements, including aluminum, arsenic, lead, and zinc.
- Observed high dissolved zinc concentrations in Spring Creek (900 μg/L) and low concentrations downstream (0.65 μg/L).
- Found that most trace elements, despite partial conversion to particulate forms in Keswick Reservoir, are transported downstream associated with colloids.
Conclusions:
- Trace elements from Iron Mountain are predominantly transported in dissolved or colloidal forms in the Sacramento River.
- Colloidal transport is a significant pathway for metal dissemination downstream, even under varying flow conditions.
- Limited removal of trace elements occurs through settling in the river system.
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