Evaluation of sulfate reduction at experimentally induced mixing interfaces using small-scale push–pull tests in an aquifer–wetland system

This paper presents small-scale push–pull tests designed to evaluate the kinetic controls on SO 4 2 - reduction in situ at mixing interfaces between a wetland and aquifer impacted by landfill leachate at the Norman Landfill research site, Norman, OK. Quantifying the rates of redox reactions initiated at interfaces is of great interest because interfaces have been shown to be zones of increased biogeochemical transformations and thus may play an important role in natural attenuation. To mimic the aquifer–wetland interface and evaluate reaction rates, SO 4 2 - -rich anaerobic aquifer water ( ∼ 100 mg / L SO 4 2 - ) was introduced into SO 4 2 - -depleted wetland porewater via push–pull tests. Results showed SO 4 2 - reduction was stimulated [...]