Light Induced Mercury Volatilization from Substrate Mechanism(s) Responsible and In situ Occurrence

EPA Grant Number: R825249
Title: Light Induced Mercury Volatilization from Substrate Mechanism(s) Responsible and In situ Occurrence
Investigators: Gustin, Mae Sexauer
Institution: University of Nevada - Reno
Current Institution: University of Nevada - Reno
EPA Project Officer: Chung, Serena
Project Period: December 15, 1996 through December 14, 1999 (Extended to December 14, 2000)
Project Amount: $288,645
RFA: Exploratory Research - Air Chemistry & Physics (1996) RFA Text |  Recipients Lists
Research Category: Engineering and Environmental Chemistry , Air

Description:

The two major objectives of this project are to determine the mechanisms responsible for light enhanced volatilization of mercury from substrate and investigate the effects of light on mercury flux in situ from anthropogenically contaminated sites. The first objective will be met by conducting experiments using a laboratory gas exchange system in which mercury containing substrate will be subjected to light of different wavelengths and intensities while maintaining other environmental conditions at a steady state. The light effects will be investigated for substrate as a function of mercury species, humic matter content, microbial activity and albedo. Chemical flux from substrate containing volatile organic species, with vapor pressure similar to mercury and that are not photoreactive, will be measured to determine if the enhanced flux is specific to mercury or due to a physical process that affects other volatile chemicals. The second objective will be met by measuring mercury flux on a diel time step at the Clear Lake and Carson River superfund sites using micrometeorological techniques to assess the effects of light on flux in situ. This study will provide information necessary for the estimation of the contribution of mercury from diffuse natural and anthropogenically contaminated sites. This study will contribute to the constantly evolving understanding of geochemical cycling of mercury in the environment.

Publications and Presentations:

Publications have been submitted on this project: View all 10 publications for this project

Journal Articles:

Journal Articles have been submitted on this project: View all 3 journal articles for this project

Supplemental Keywords:

mercury, volatilization, in situ, geochemical, microbial, volatile organic, micrometeorological, Scientific Discipline, Air, Water, air toxics, Environmental Chemistry, Ecology and Ecosystems, Mercury, anthropogenic disturbances, geochemical cycling, contaminated sites, Superfund sites, photoreactive, exposure and effects, chemical flux, volatile organic species, mercury cycling, light induced mercury volatilization, air-water interface, lake ecosystems

Progress and Final Reports:

  • 1997 Progress Report
  • 1998 Progress Report
  • 1999 Progress Report
  • Final Report