DNAPL Dissolution in Fractures and Fracture Networks(Abstract)

摘要

Processes impacting the dissolution of dense non-aqueous phase liquids (DNAPLs) in fractured bedrock are not well understood, thereby limiting efforts to predict the longev- ity of DNAPL sources, select the appropriate remedial technologies, effectively design and implement the selected in situ technologies, evaluate remedial performance, and estimate the time needed to remediate a DNAPL source zone. The rate of DNAPL disso- lution is typically controlled by interfacial mass transfer between the DNAPL and sur- rounding groundwater, especially during implementation of in situ remedial technologies such as chemical oxidation and bioaugmentation. Thus, changes in the effective DNAPL- water interfacial area in bedrock fractures due to dissolution of the DNAPL source will have a substantial impact on the overall remedial process. The presence of oxidation precipitates, biofilm growth, and dead-end fractures can also impact overall DNAPL dissolution rates. However, comprehensive studies have hitherto not been performed to evaluate and quantify these phenomena in fractured bedrock systems.