Technical Approach

Methods developed under previous DoD funding will be extended to include performance and cost functions for thermal conduction heating, steam injection, and in situ chemical oxidation methods as well as electric resistance heating, enhanced bioremediation, and monitored natural attenuation. Effects of back-diffusion from low permeability zones will be considered using a computationally efficient upscaled approach with options to output either resident or flux concentrations as needed to correspond to field data obtained by various means. An inverse solution will enable estimation of model parameters and their uncertainty using available field and laboratory data as well as prior estimates of parameters and their uncertainty, and a stochastic optimization technique will be used to determine optimum operational and monitoring variables to minimize the average cost over multiple realizations of uncertain parameters and measurements. Methods will be developed and tested to periodically estimate the value of additional characterization data in terms of life cycle cost savings, to refine model calibration taking into account new data from monitoring, to assess the probability of the current operations to meet cleanup objectives, and to reoptimize system operation and monitoring variables to minimize expected life cycle cost taking into consideration performance and cost uncertainty. Numerical methods will be verified against known solutions, and the integrated methodology will be demonstrated using "virtual site" data from SERDP project ER-2313 and from several actual DoD sites in collaboration with Army, Navy, and Air Force personnel. A number of avenues will be followed to achieve technology transfer to DoD site managers, regulators, and consultants.