A quantitative framework for understanding complex interactions between competing interfacial processes and in situ...

Area of Science:

• Environmental Science
• Geochemistry
• Microbiology

Background:

• Subsurface heterogeneity complicates in situ bioremediation of contaminated groundwater.
• Heterogeneities impact mass transfer, affecting microbial substrate availability and overall remediation rates.

Purpose of the Study:

• To evaluate a quantitative framework using dimensionless coefficients for assessing field-scale bioremediation.
• To demonstrate the framework's utility in identifying rate-limiting processes and predicting effective engineered enhancements.

Main Methods:

• Numerical modeling experiments to simulate bioremediation under varying rate-limiting conditions (dispersion, biokinetics, sorption).
• Application of the quantitative framework to analyze large-scale laboratory and field experiments using reported parameter estimates.

Main Results:

• The framework successfully identified rate-limiting processes in numerical models.
• Engineered treatments predicted by the framework were more effective in enhancing biodegradation than alternative approaches.
• Framework predictions aligned with observations from laboratory and field-scale experiments.

Conclusions:

• The quantitative framework provides a robust tool for evaluating and optimizing in situ bioremediation strategies.
• Understanding and addressing rate-limiting processes through targeted enhancements is crucial for effective groundwater remediation.