Organic contaminant transport and fate in the subsurface: evolution of knowledge and understanding

Water Resources Research
By: , and 

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Abstract

Toxic organic contaminants may enter the subsurface as slightly soluble and volatile nonaqueous phase liquids (NAPLs) or as dissolved solutes resulting in contaminant plumes emanating from the source zone. A large body of research published in Water Resources Research has been devoted to characterizing and understanding processes controlling the transport and fate of these organic contaminants and the effectiveness of natural attenuation, bioremediation, and other remedial technologies. These contributions include studies of NAPL flow, entrapment, and interphase mass transfer that have advanced from the analysis of simple systems with uniform properties and equilibrium contaminant phase partitioning to complex systems with pore-scale and macroscale heterogeneity and rate-limited interphase mass transfer. Understanding of the fate of dissolved organic plumes has advanced from when biodegradation was thought to require oxygen to recognition of the importance of anaerobic biodegradation, multiple redox zones, microbial enzyme kinetics, and mixing of organic contaminants and electron acceptors at plume fringes. Challenges remain in understanding the impacts of physical, chemical, biological, and hydrogeological heterogeneity, pore-scale interactions, and mixing on the fate of organic contaminants. Further effort is needed to successfully incorporate these processes into field-scale predictions of transport and fate. Regulations have greatly reduced the frequency of new point-source contamination problems; however, remediation at many legacy plumes remains challenging. A number of fields of current relevance are benefiting from research advances from point-source contaminant research. These include geologic carbon sequestration, nonpoint-source contamination, aquifer storage and recovery, the fate of contaminants from oil and gas development, and enhanced bioremediation.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Organic contaminant transport and fate in the subsurface: evolution of knowledge and understanding
Series title Water Resources Research
DOI 10.1002/2015WR017121
Volume 51
Issue 7
Year Published 2015
Language English
Publisher American Geophysical Union
Publisher location Washington, D.C.
Contributing office(s) National Research Program - Western Branch, Toxic Substances Hydrology Program
Description 42
First page 4861
Last page 4902
Online Only (Y/N) N
Additional Online Files (Y/N) N