In situ Bioremediation Process Engineering Concepts

• Published in: Fundamentals and Applications Vol. 1; pp. 633 - 664
• Main Authors: Cunningham, A. B., Sturman, P. J.
• Format: Book Chapter
• Language: English
• Published: United Kingdom CRC Press 1998; CRC Press LLC
• Edition: 1
• Subjects: Waste management; Advective Dispersive Transport; NAPL; Heterotrophic Plate Counts; MPN Technique; Limits Biodegradation; DNA Probe; Kinetic Reaction Rate; DNAPL; Hydrocarbon Degrader; Bioremediation Process; Species Predominance; Electron Acceptor Conditions; Fractional Order Dependence; Laboratory Scale Experimental System; Field Measurement Conditions; Subsurface Environmental Conditions; Degrader Microorganisms; Initial Substrate Concentration; Contaminant Removal; Interphase Transport; Nonequilibrium Sorption; Slow Desorption Rate; Electron Acceptor; Biotransformation Rate; Spatial Heterogeneity
• ISBN: 9781566763080; 1566763088
• DOI: 10.1201/9780203755389-18

This chapter provides a framework for understanding factors affecting biotransformation rate and extent with the intent of improving the design of subsurface bioremediation systems. Methods of bacterial enumeration from soil or water systems include heterotrophic plate counts, epifluorescence direct counts, hydrocarbon degrader plate counts, most probable number techniques, DNA probes, lipid assays, metabolic indicators, and radioisotopic methods. Direct counts include both metabolically active and inactive organisms, while heterotrophic plate counts theoretically measure only the fraction capable of growth. Spatial heterogeneity at contaminated field sites can significantly influence contaminant movement and rate of degradation. Subsurface properties that are subject to significant spatial variation include porosity, permeability, degree of microbial colonization, and chemical properties such as nutrient and electron acceptor conditions. Contaminant disappearance from a field site may occur for a variety of reasons, including volatilization, off-site migration, sorption onto soil particles, and abiotic transformation, thereby complicating the measurement of in situ bioremediation rates.