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Project Title: Sources of Atmospheric Mercury and Trace Metal Deposition
Mendenhall Fellow: Mark Engle, (703) 648-6454, engle@usgs.gov
Duty Station: Reston , Virginia
Start Date: October 3, 2005
Education: Ph.D., Hydrogeology, University of Nevada, Reno (2005)
Research Advisors: Allan Kolker, (703) 648-6418, akolker@usgs.gov; David Krabbenhoft , (608) 821-3843, dpkrabbe@usgs.gov
Project Description: Atmospheric transport and subsequent wet and/or dry deposition is an important pathway for Hg and other metals to be introduced to the environment. The focus of this research is to apply geochemical, statistical, and air mass trajectory modeling techniques to identify potential sources of trace metals, in particular mercury (Hg), in aerosols and precipitation that can be readily deposited to surface environments. These techniques will be applied to Hg and trace metal data from the Culpeper, Virginia Mercury Deposition Network site (VA08) as well as other sites where the USGS Mobile Hg Laboratory is stationed, such as southern Alabama. The USGS Mobile Hg Laboratory allows for near real-time speciation of atmospheric Hg as either elemental Hg, reactive gaseous Hg, or particulate Hg. Speciation data are particularly critical in understanding the potential ecosystem inputs as deposition velocities for reactive gaseous Hg and particulate Hg are orders of magnitude larger than for elemental Hg.
24-hour HYSPLIT air mass backward trajectory model at final heights of 150m, 500m, and 1000m for 4/30/05 at 12 PM UTC (8AM EST) time for the Culpeper, Virginia Mercury Deposition Network site. This figure illustrates the potential source areas for Hg and other trace metals that were measured in the weekly MDN precipitation sample that was dominated by this single rain event on the morning of April 30, 2005.
USGS Mobile Hg Laboratory. Instruments include an atmospheric Hg speciation unit; NOx, SOx, O3, and PM2.5 analyzers; a metereorogical station; and a wet deposition sampler.
Plot of preliminary reactive gaseous Hg, particulate Hg, and elemental Hg concentration data determined by the atmospheric Hg speciation unit on the USGS Mobile Hg Laboratory for the Weeks Bay, Alabama site from June 6, 2005, to June16, 2005 (Julian days 157 to 167). The gap in the data are a result of the trailer being shut down during Tropical Storm Arlene.
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Last modified: 16:08:27 Thu 13 Dec 2012