Philip Swartzendruber Eric Prestbo Colleen A. Caldwell 2006 <p>This research was initiated to characterize atmospheric deposition of reactive gaseous mercury (RGM), particulate mercury (HgP; &lt;2.5 &mu;m), and gaseous elemental mercury (Hg⁰) in the arid lands of south central New Mexico. Two methods were field-tested to estimate dry deposition of three mercury species. A manual speciation sampling train consisting of a KCl-coated denuder, 2.5 &mu;m quartz fiber filters, and gold-coated quartz traps and an ion-exchange membrane (as a passive surrogate surface) were deployed concurrently over 24-h intervals for an entire year. The mean 24-h atmospheric concentration for RGM was 6.8 pg m^-3<span>&nbsp;with an estimated deposition of 0.10 ng m</span>^-2<span>h</span>^-1. The estimated deposition of mercury to the passive surrogate surface was much greater (4.0 ng m^-2<span>h</span>^-1) but demonstrated a diurnal pattern with elevated deposition from late afternoon to late evening (1400&minus;2200; 8.0 ng m^-2<span>h</span>^-1) and lowest deposition during the night just prior to sunrise (2200&minus;0600; 1.7 ng m^-2h^-1). The mean 24-h atmospheric concentrations for HgP and Hg⁰<span>&nbsp;were 1.52 pg m</span>^-3<span>&nbsp;and 1.59 ng m</span>^-3, respectively. Diurnal patterns were observed for RGM with atmospheric levels lowest during the night prior to sunrise (3.8 pg m-3) and greater during the afternoon and early evening (8.9 pg m^-3). Discernible diurnal patterns were not observed for either HgP or Hg⁰. The total dry deposition of Hg was 5.9 &mu;g m^-2 year-1<span>&nbsp;with the contribution from the three species as follows:&thinsp; RGM (0.88 &mu;g m</span>^-2<span>&nbsp;year</span>^-1), HgP (0.025 &mu;g m^-2<span>&nbsp;year</span>^-1), and Hg⁰<span>&nbsp;(5.0 &mu;g m</span>^-2<span>&nbsp;year</span>^-1). The annual wet deposition for total mercury throughout the same collection duration was 4.2 &mu;g m^-2<span>&nbsp;year</span>^-1, resulting in an estimated total deposition of 10.1 &mu;g m^-2&nbsp;year^-1<span>&nbsp;for Hg. On one sampling date, enhanced HgP (12 pg m</span>^-3) was observed due to emissions from a wildfire approximately 250 km to the east.</p> application/pdf 10.1021/es0609957 en American Chemical Society Concentration and dry deposition of mercury species in arid south central New Mexico (2001-2002) article