Grantee Research Project Results
Biogeochemistry of Arsenic and Its Extraction From Soil
EPA Grant Number: U915037Title: Biogeochemistry of Arsenic and Its Extraction From Soil
Investigators: Thomas, John E.
Institution: University of Florida
EPA Project Officer: Hahn, Intaek
Project Period: January 1, 1996 through December 28, 1999
Project Amount: $102,000
RFA: STAR Graduate Fellowships (1996) RFA Text | Recipients Lists
Research Category: Academic Fellowships , Ecological Indicators/Assessment/Restoration , Fellowship - Earth Sciences
Objective:
The objective of this research project is to explore potential effective means of remediating arsenic-contaminated soil through extraction, mobilization, or volatilization of arsenic.
Approach:
The first area of investigation involves chemical
complexation and extraction of the arsenical oxyanions (oxygenated negative
ions) by an aqueous
solution of sodium dodecylsulfate mixed with a highly positive-charged macrocycle
(compound containing a ring consisting of 15 atoms) synthesized from
vitamin B1. The ability to extract arsenic coupled with the expected biodegradability
of the organic extractants makes this system a strong candidate for classical
pump-and-treat remediation or other soil flushing/washing procedures. The
second thrust of this study involves the biological volatilization of arsenic.
Field
studies are conducted to assess volatilization rates off the soil surface
using soil gas flux collection boxes. The subsurface flux also is determined
using
depth probes to collect arsenical gases onto activated charcoal. Laboratory
studies are conducted to find arsenic volatilization rates under various
oxic (oxygenated) conditions for soil and for mineral culture media inoculated
with
microorganisms isolated from these contaminated soils. This project consists
of six distinct phases: (1) site identification; (2) quantification of the
amount and location of arsenic in the soil; (3) evaluation of the chemical
extraction procedure of arsenic from the different soil types; (4) testing
of the soil for biological volatilization of arsenic; (5) isolation and testing
of microorganisms responsible for arsenic volatilization; and (6) determination
of the rates of arsenic transformation to volatile compounds by these microorganisms
under various oxic conditions.
Supplemental Keywords:
fellowship, arsenic, As, soil, organic extractants, arsenic volatilization rates, contaminated soils, volatile organic compounds, VOCs., RFA, Health, Scientific Discipline, INTERNATIONAL COOPERATION, Water, Waste, POLLUTANTS/TOXICS, Environmental Chemistry, Contaminated Sediments, Health Risk Assessment, Geochemistry, Arsenic, Risk Assessments, Hazardous Waste, Water Pollutants, Hazardous, contaminant transport, Superfund sites, contaminated sediment, sediment transport, risk management, contaminated soil, sediment quality survey, superfund site, arsenic mobility, assessment methods, water quality, ecology assessment models, biogeochemistry, water treatment, arsenic exposure, soil flushingProgress and Final Reports:
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.