Arsenic and antimony speciation in water and bottom sediments associated with geothermal waste fluids: Dachny geothermal field, Kamchatka, Russia

GEOC 129

Anastasia G. Ilgen, ftagt@uaf.edu1, Seth Mueller, muellersh@gmail.com2, M. Newville, newville@cars.uchicago.edu3, and Thomas P. Trainor1. (1) Department of Chemistry and Biochemistry, University of Alaska Fairbanks, 900 Yukon Drive, Rm. 194, P.O. Box 756160, Fairbanks, AK 99775, (2) U.S. Geological Survey, Box 25046 MS 973 BLDG 20, Denver Federal Center, Denver, CO 80225, (3) Consortium for Advanced Radiation Sources and Department of Geophysical Sciences, University of Chicago, Chicago, IL 60637
An emerging issue related to the use of geothermal fluids for power production is the potential for surface water contamination. We have examined the arsenic and antimony speciation and the extent of transport associated with the release of spent geothermal waters at Dachny geothermal field, Kamchatka Russia. The field site is a high temperature hydrothermal field, used for electricity production. In the spent fluids, the average concentrations of As is 10 ppm and Sb is 118 ppb. The As and Sb speciation in aqueous phase have been examined using liquid chromatography (LC) coupled with ICP-MS as a function of distance from source and water chemistry. The wet fractions of bottom sediments were analyzed for As speciation using synchrotron based extended x-ray absorption fine structure (EXAFS) spectroscopy, which confirmed the presence of both As(III) and As(V) in the sediments. The results of our analyzes will be discussed.
 

Speciation of Arsenic and Other Trace Elements in Soils and Sediments
1:25 PM-5:10 PM, Wednesday, April 9, 2008 Morial Convention Center -- Rm. 211, Oral

Division of Geochemistry

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008