Selenium removal processes from Great Salt Lake, Utah: estimating sedimentation and verifying volatilization fluxes

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Publication Type thesis
School or College College of Mines & Earth Sciences
Department Geology & Geophysics
Author Oliver, Wade Austin
Title Selenium removal processes from Great Salt Lake, Utah: estimating sedimentation and verifying volatilization fluxes
Date 2008-05
Description Removal processes for selenium (Se) from the Great Salt Lake, Utah (GSL) are investigated by estimation of sedimentation flux from analysis of lake cores and direct measurement of volatilization flux for comparison to a predictive model. To estimate Se removal by sedimentation, lake sediment cores were used to delineate qualitative sedimentation regions, estimate mass accumulation rates (MAR), and determine sediment 210 226 7 137 Se concentrations. Quantifiable MAR results from analysis of Pb, Ra, Be, and Cs activity in 8 deep cores ranged from 0.010 to 0.049 g/cm2/yr. Contemporary sediment Se concentrations from the upper 2 cm of each deep core ranged from 0.79 to 3.12 |ig/g. A representative MAR and Se concentration was assigned based on deep cores located within each sedimentation region. Coupling these with region area, mean annual Se removal by sedimentation was estimated to be 520 Kg/yr within a range of uncertainty between 45 and 990 Kg/yr. Volatilized Se from the water surface was contained and concentrated using a floating emission isolation flux chamber (St. Croix Sensory, Inc.) and captured in a cryogenic finger trap. These samples were taken concurrently with volatile Se concentration, wind velocity, and surface water temperature for input into the Se flux predictive model. Direct flux measurements under controlled laboratory conditions in which Se concentration varied and was independently verified suggest that 10% of actual flux was captured by the direct measurement. After correction for background and 10% measurement inefficiency, measured fluxes approximated, but were generally higher than predicted fluxes. The specific cause of this discrepancy is unclear, but the correspondence is strong enough with the limited number of direct measurements that a correction of the predicted flux is not warranted. The results of these two investigations compared to estimated loadings of Se suggest that volatilization, not permanent sedimentation, is primary removal process for Se from the GSL.
Type Text
Publisher University of Utah
Subject Lake sediments, Utah, Great Salt Lake;Selenium, Utah, Great Salt Lake; Great Salt Lake (Utah)
Dissertation Institution University of Utah
Dissertation Name MS
Language eng
Relation is Version of Digital reproduction of "Selenium removal processes from Great Salt Lake, Utah: estimating sedimentation and verifying volatization fluxes" J. Willard Marriott Library Special Collections, GB9.5 2008 .O44
Rights Management © Wade Austin Oliver
Format Medium application/pdf
Format Extent 126,314 bytes
Identifier us-etd2,29184
Source Original: University of Utah J. Willard Marriott Library Special Collections
ARK ark:/87278/s6s18h5g
Setname ir_etd
ID 193919
Reference URL https://collections.lib.utah.edu/ark:/87278/s6s18h5g