HR: 0830h
AN: NS51B-01    [Abstracts]
TI: The Influence of Bacterial Activity on the Speciation and Transport of Arsenic Across the Ground Water-Surface Water Transition Zone at a Contaminated Site
AU: * Ford, R
EM: ford.robert@epa.gov
AF: USEPA National Risk Management Research Laboratory, 919 Kerr Research Dr., Ada, OK 74820 United States
AU: Wilkin, R
EM: wilkin.rick@epa.gov
AF: USEPA National Risk Management Research Laboratory, 919 Kerr Research Dr., Ada, OK 74820 United States
AU: Beck, F
EM: beck.frank@epa.gov
AF: USEPA National Risk Management Research Laboratory, 919 Kerr Research Dr., Ada, OK 74820 United States
AU: Clark, P
EM: clark.patrick@epa.gov
AF: USEPA National Risk Management Research Laboratory, 26 West Martin Luther King Dr., Cincinnati, OH 45268 United States
AU: Creed, J
EM: creed.jack@epa.gov
AF: USEPA National Exposure Research Laboratory, 26 West Martin Luther King Dr., Cincinnati, OH 45268 United States
AU: Creed, P
EM: gallagher.patricia@epa.gov
AF: USEPA National Exposure Research Laboratory, 26 West Martin Luther King Dr., Cincinnati, OH 45268 United States
AB: Field investigations have been conducted to understand the fate of arsenic in contaminated ground water during discharge into a small lake. The ground water plume contains elevated levels of arsenic and BTEX compounds derived from historical disposal of process wastes from up gradient industrial activities. A ground-water monitoring network was established in conjunction with the collection of surface water and sediment samples to establish the extent and characteristics of the zone of contaminant discharge into the small lake. Examination of the spatial patterns of specific conductance in ground water and surface water along with sediment characteristics have been used to develop a conceptual model of the biogeochemical processes controlling the speciation and transport of arsenic across the ground water-surface water transition zone. Patterns in specific conductance and sediment mineralogy point to the importance of bacterial iron and sulfate reduction processes. Spatial relationships between these indicator parameters and arsenic speciation in ground water at the point of plume discharge indicate that degradation of BTEX compounds and other hydrocarbons influences the ultimate fate of arsenic within the system. Notice: This is an abstract of a proposed presentation and does not necessarily reflect EPA policy.
DE: 1045 Low-temperature geochemistry
DE: 1832 Groundwater transport
DE: 1871 Surface water quality
SC: Near-Surface Geophysics [NS]
MN: 2005 Joint Assembly