Wednesday, April 2, 2008 : 9:00 a.m.

Using Polymer Floods to Overcome Heterogeneity Effects during Bioremediation and Chemical Oxidation Ground Water Treatments

Megan M. Smith1, Jeff A.K. Silva2, Junko Munakata-Marr, Dr.1 and John E. McCray1, (1)Colorado School of Mines, (2)Environmental Science & Engineering Division

Due to preferential ground water flow through high-permeability areas, injected remediation agents may not effectively contact compounds trapped in lower-permeability lenses throughout heterogeneous aquifers, and thus contaminated regions may persist in an otherwise treated ground water system.  Polymer flooding, coupled with conventional remediation agents, can reduce flow bypassing in natural systems and encourage flow throughout all layers, creating a more thorough treatment agent distribution.  If chemical compatibility can be demonstrated between polymers and selected remediation agents, then the efficiency of a given ground water treatment may be significantly improved by the joint use of a polymer flood.  To this end, we present the results of a range of batch tests and column experiments utilizing polymers coupled with both chemical oxidants and an anaerobic microbial culture capable of biodegradation.  Test contaminants include the chlorinated solvents tetrachloroethene (PCE) and trichloroethene (TCE).  Compatibility data provide details concerning contaminant degradation rates and the possible utilization of polymers as secondary electron donors in xanthan solutions.  Polymer-oxidant experiments with xanthan and potassium permanganate as well as column transport results are discussed in the context of possible larger-scale applications.  These findings provide the basis for a novel coupled ground water technology which has potential for increasing the efficiency of aquifer clean-up.  Additional considerations for larger field-scale implementation, such as natural oxidant demand, effective polymer concentrations, and the scale of heterogeneities over which polymer-enhanced treatment may be possible, are reviewed. 

Megan M. Smith, Colorado School of Mines Megan M. Smith is currently completing her graduate research in Hydrologic Science at the Colorado School of Mines. Her thesis research involves the demonstration of chemical compatibility between polymer floods and conventional groundwater remediation techniques for increased clean-up efficiency.

2008 Ground Water Summit