Engineered Injection And Extraction For Enhanced Mixing In Groundwater To Improve In-Situ Remediation
Piscopo, Amy N 1 ; Neupauer, Roseanna M 2 ; Mays, David C 3
1 ºù«ÍÞÊÓƵ
2 ºù«ÍÞÊÓƵ
3 University of Colorado Denver
Creating favorable mixing conditions in aquifers has the potential to improve the efficiency of in-situ remediation of groundwater. In current practice of in-situ remediation, the treatment solution, containing chemical or biological amendments, is either drawn through the aquifer using a downgradient extraction well or left to travel with ambient groundwater flow. Neither of these scenarios provides opportunity to enlarge the interfacial area between the treatment solution and the contaminated groundwater where degradation reactions occur. We hypothesize that by sequentially injecting or extracting clean water at multiple wells in the aquifer, the interface between the treatment solution and the contaminated groundwater can be stretched and folded to create unique geometries that provide additional surface area for reaction, thereby accelerating the treatment process. This strategy of injection and extraction is expected to be feasible for practical application since the pumping duration is limited as compared to other methods of injection and extraction, for example the pulsed dipole approach investigated by others. Simulations are conducted to model the reaction that occurs during a particular sequence of injection and extraction in both homogeneous and heterogeneous media. The results are compared to the reaction that occurs during a typical in-situ remediation scenario, where the treatment solution travels with ambient groundwater flow.