Influence of Water Table Fluctuation on Natural Source Zone Depletion in Hydrocarbon Contaminated Subsurface Environments
Abstract
Most of the prediction theories regarding dissolution of organic contaminants in the
subsurface systems have been proposed based on the static water conditions and
the influence of water fluctuations on mass removal requires further investigations.
In this study, it was intended to investigate the effects of water table fluctuations on
biogeochemical properties of the contaminated soil at the smear zone between the vadose
zone and the groundwater table. An automated 60 cm soil column system was developed
and connected to a hydrostatic equilibrium reservoir to impose the water regime by
using a multi-channel pump. Four homogenized hydrocarbon contaminated soil columns
were constructed and two of them were fully saturated and remained under static water
conditions while another two columns were operated under water table fluctuations
between the soil surface and 40 cm below it. The experiments were run for 150 days and
relevant geochemical indicators as well as dissolved phase concentrations were analyzed
at 30 and 50 cm below the soil surface in all columns. The results indicated significant
difference in terms of biodegradation effectiveness between the smear zones exposed to
static and water table fluctuation conditions. This presentation will provide an overview
of the experimental approach, mass removal efficiency, and key findings.
Collections
- Civil and Environmental Engineering [851 items ]
- Theme 3: Geotechnical, Environmental, and Geo-environmental, Engineering [21 items ]