Modeling of Ground Water Aquifer Remediation by Pulsed Pumping When Contaminant Transport is Affected by Physical, Non-Equilibrium Sorption and Desorption
Abstract
This research postulates and demonstrates incorporating rate-limited sorption effects in the USGS SUTRA code for cleanup of a hypothetical sandy aquifer by pump-and-treat remediation methods. Contaminant transport is assumed to be affected by advection, dispersion, and rate-limited sorption/desorption. Sorption is assumed to be either equilibrium or rate-limited, with the rate- limitation described by either a first-order law, or by Fickian diffusion of contaminant through a spherical immobile pore region. Solutions are arrived at by split operator methods for the transport and one-dimensional Galerkin solutions for the solute concentration equations. The resulting model is tested against an analytical Laplace transform model for both first-order and Fickian diffusion methods in a radial pumping simulation. Model simulations are used to evaluate equilibrium, first-order and Fickian diffusion effects for pulsed and continuous pumping solutions within a hypothetical sandy aquifer. These show that equilibrium methods under-predicted rebound while first-order methods may both under and over predict rebound within the matrix for certain regions and may be equivalent to Fickian diffusion in equilibrium regimes for cleanup time prediction. Model simulations are then used to show the efficiency of pulsed pumping methods in cleanup mass extraction per pumped volume for a contaminated aquifer pump-and-treat remediation activity versus more conventional, continuous pumping methods. Physical Non-Equilibrium, Rate-Limited Sorption, Fickian Diffusion, SUTRA, Pump-and-Treat, Pulsed Pumping
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 12, 1994
- Accession Number
- ADA284888
Entities
People
- Jeffrey L. Caspers
Organizations
- Air Force Institute of Technology