Diagnostic Tools for the Monitoring and Organization of In-Situ Air Sparging Systems
1998
Amerson, Illa L.
In situ air sparging (IAS) involves injecting air into an aquifer to treat trapped contaminant sources, remediate dissolved contaminant plumes, and mitigate dissolved contaminant plume migration. The injected air also provides a source of oxygen for aerobic biodegradation of contaminants. Although the principle of the technology is simple, the practical aspects of effectively monitoring and optimizing IAS systems remain problematic. Conventional monitoring approaches generally focus on assessing the air distribution within the aquifer. There is a need, however, for methods to measure mass transfer or treatment rates at points within the target treatment zone in order to monitor the system's performance. The goal of this research was to develop diagnostic tools for quantifying mass transfer rates during IAS operation. Experiments have focused on two alternatives: (a) a push-pull test using a multi-component tracer solution, and (b) a continuous ground water pumping test coupled with injecting sulfur hexafluoride through the air injection well. The multi-component tracer solution was developed and tested under controlled experimental conditions in a three-dimensional tank. Both the multitracer solution and the continuous pumping SF6 test were field tested at the U.S. Navy National Test Site at Port Hueneme, California. The three-dimensional tank and field data indicate that the diagnostic tools are appropriate for assessing mass transfer at IAS sites. Two oxygen transfer rates, one indication oxygen consumption and one indicating oxygen delivery, have been derived from the tracer test data.
显示更多 [+] 显示较少 [-]