ABSTRACT
The effectiveness of the solid oxygen sources technique that is used to enhance bioremediation of contaminated groundwater sites is evaluated in this paper. The finite element model (METABIOTRANS), which simulates the fate and transport of contaminants in the subsurface, is used in this assessment study. Several scenarios were simulated to examine the sensitivity of remediation effectiveness to the number and locations of oxygen sources. Results show that an injection source placed near the plume core, where highest contaminant concentrations exist, is always desired. The nearest injection oxygen source to the contaminant source zone caused higher stimulation to bacterial growth than further down-gradient injection oxygen sources. It also exhibited longer resident time of the oxygen in the aquifer; and therefore, yielded higher biodegraded contaminant mass. Higher injection rates of oxygen are not always needed to increase bioremediation efficiency. This should be noticed in real practices of groundwater remediation design.
