Grantee Research Project Results

Dissolution Dynamics of Multiple Component NAPLs In Aqueous and Surfactant/Cosolvent Systems

EPA Grant Number: R827112
Title: Dissolution Dynamics of Multiple Component NAPLs In Aqueous and Surfactant/Cosolvent Systems
Investigators: Brusseau, Mark
Institution: University of Arizona
EPA Project Officer: Aja, Hayley
Project Period: September 1, 1998 through August 31, 2001 (Extended to December 20, 2002)
Project Amount: $362,453
RFA: Exploratory Research - Physics (1998) RFA Text | Recipients Lists
Research Category: Land and Waste Management , Air , Safer Chemicals

Description:

The overall goal of the proposed research is to enhance our understanding of the dissolution of non-ideal, multiple-component, nonaqueous phase (immiscible) organic liquids (NAPLs) in subsurface systems. The specific objectives are:

Investigate the effect of NAPL composition-dependent factors on dissolution of three- component NAPLs in groundwater.
Investigate the effect of NAPL composition and mass-transfer limitations on the enhanced dissolution of three-component NAPLs caused by solubilization agents.
Investigate the effect of NAPL composition and mass-transfer limitations on the dissolution of multiple (>10)-component NAPLs in water and enhanced-solubilization solutions.
Analyze results from a (completed) subsurface remediation field test to elucidate the factors influencing NAPL dissolution.

Approach:

The goal of this research is to investigate the effects of compositional factors (such as mole fraction and activity coefficients) and mass-transfer limitations on dissolution of organic mixtures into ground water and remediative flushing fluids. A major difficulty associated with this investigation is to simultaneously characterize the impact of (1) composition-dependent factors on equilibrium dissolution, (2) the hydrologic and physicochemical (but not composition-dependent) effects on rate-limited dissolution, and (3) the composition-dependent factors on rate-limited dissolution of both ideal and non-ideal mixtures. This is addressed by taking a multi-step approach where these factors will first be characterized separately, and then integrated by the use of combined experimental systems and mathematical modeling. The results of the study will then be used to evaluate data obtained from a field test of in-situ flushing completed at a NAPL-contaminated site in Utah.

Expected Results:

A review of the literature indicates that no detailed research has been completed on non-equilibrium mass transfer of non-ideal, multicomponent NAPLs, even though many waste sites contain complex organic mixtures. The results of the proposed research will enhance our understanding of rate-limited dissolution of NAPL mixtures in subsurface systems. These results would significantly improve risk identification and assessment, and the design of remediation schemes. The results will also be pertinent to the question of risks associated with alternative cleanup standards or endpoints.

Publications and Presentations:

Publications have been submitted on this project: View all 11 publications for this project

Journal Articles:

Journal Articles have been submitted on this project: View all 2 journal articles for this project

Supplemental Keywords:

groundwater contamination, soil contamination, soil & groundwater remediation, aquifer flushing,, RFA, Scientific Discipline, Water, Geographic Area, Waste, Ecosystem Protection/Environmental Exposure & Risk, Physics, Environmental Chemistry, Remediation, Restoration, State, chemical mixtures, Aquatic Ecosystem Restoration, Engineering, Chemistry, & Physics, Groundwater remediation, groundwater recharge, NAPL, aquifer flushing, Utah (UT), mass transfer, dissolution dynamics, aquifer remediation design, alternative cleanup standards, soil and groudwater remediation, aquatic ecosystems, groundwater contamination, surfactants, cosolvent systems, NAPLs

Progress and Final Reports:

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.