Groundwater redox conditions at a petroleum contaminated site, Kuils River, South Africa : pathways for BTEX biodegradation

A shallow sandy aquifer, contaminated by petrol from an underground storage tank, was studied to determine if intrinsic bioremediation of the hydrocarbons is taking place. Groundwater samples taken from 32 monitoring wells were analysed for NO₃-,NH₄+, Mn²+, Fe²+, SO₄²-, and ΣH₂S. Portable electrodes were used to make field measurements of electrical conductivity, redox potential, and pH. The variation and distribution of these redox-sensitive groundwater constituents show that bioremediation via NO₃- reduction, Fe³+ reduction, and SO₄²- reduction (and possibly methanogenesis in the most reduced part of the plume) is occurring. In some cases redox processes are taking place simultaneously resulting in redox zones that overlap. Iron and sulphate reduction are the dominant processes taking place.

Grantor dc:publisher.institution

Department of Geological Sciences

Year dc:date.issued

2003

Author dc:creator

• Merrett, Greg Lee

Advisor dc:contributor.advisor

• Roychoudhury, Alakendra N

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/8588

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/8588