The objective of this proposal are to conduct theoretical work on the experimental design problem in coupled groundwater supply and water quality systems, and to evaluate the developed design methodology by conducting modified pump tests in the Borden aquifer, for which the hydraulic and mass transport parameters have already been determined by other field studies. The experimental design problem includes the determination of the optimal experimental conditions for estimation of the hydraulic and mass transport parameters in groundwater systems. The experimental conditions define the location, timing and magnitude of groundwater pumping or recharge, the location of observation wells in the aquifer system, and the sampling frequency and duration of the experiment. The experimental conditions, which are based on cost, reliability, and identifiability criteria, are designed, from a management and prediction perspective, to provide optimal information for parameter estimation, and as a result, minimize the ill- posedness of the identification process. The laboratory and field tasks are expected to refine understanding of the sorptive characteristics of the Borden aquifer for several organic solutes (for which extensive transport data are already available), and then implement a modified pump test in the Borden aquifer in which inorganic tracers and the organic solutes are injected. The modified pump test will be designed for optimal estimation of the hydraulic and mass transport parameters. The design will then be evaluated by comparing the estimated parameters to those determined by other field and laboratory studies. Results of this research are expected to be useful in determining identifiability criteria for hydraulic and mass transport parameters, the trade-offs associated with monitoring network costs and reliability, and provide baseline information for the design and operation of groundwater monitoring networks.
