The mechanisms for EK-induced mixing to enhance bioremediation will vary depending on the host geological matrix.
Novel field-scale applications of EK-BIO exist including the remediation of plume-scale contaminant scenarios and contaminants
sequestered within zones of low permeability.
When EK is applied in the natural environment, complex physicochemical processes generate non-uniform pH, voltage and moisture gradients that can affect bioremediation performance and need to be considered on a site-specific basis, for example, groundwater flow will influence amendment transport and pH changes at the electrodes.
Numerous electrode material and configuration options exist to optimise the EK-BIO treatment.
Simple modelling of a relevant contaminated groundwater conceputal scenario to illustrate the performance of EK-BIO at the field-scale indicates that a considerable reduction in the time for a plume to reach steady-state length can be achieved. Relative to timescales which may typically occur for sites managed using MNA, EK-BIO could reduce overall remediation costs significantly.
Research is needed to investigate how EK-BIO responds to the complexity of typical field-scale applications, these include:
A better understanding of the effect of natural aquifer settings on EK-BIO processes including groundwater flow and physical, geological and electrolyte heterogeneity.
The effectiveness of EK-BIO applied to novel contaminants as well as organic and inorganic contaminant mixtures.
Combinations with other remediation technologies such as PRBs, chemical oxridation/reduction and phytoremediation.
Electrode configurations and treatment optimisation to accomodate field-scale complexity and affects of EK on microbial
communities.
Furthermore, good practice guidelines on EK-BIO implementation at the field-scale could be developed to support the application of well designed and effective EK-BIO treatment, without unintended adverse effects.