Dense Nonaqueous-Phase Liquids and Flux-Based Site Management

Introduction

Dense Nonaqueous-Phase Liquids and Flux-Based Site Remediation DNAPLs are organic liquids with a density greater than water. They include solvents, coal tar, and creosotes. Contamination of groundwater can occur as a result of dissolved plumes generated from DNAPL source zones. DNAPLs pose significant challenges in site remediation.

Projects Current Projects Impact of Clay-DNAPL Interactions on Transport and Storage of Chlorinated Solvents in Low-Permeability Zones (PDF) (1 pp, 114 KB) Predicting DNAPL Source Zone and Plume Response Using Site-Measured Characteristics (PDF) (1 pp, 40 KB) Previous Projects Enhanced Source Removal (PDF) (2 pp, 125 KB)Contact: Lynn Wood Impacts of DNAPL Source Zone Treatment: Experimental and Modeling Assessment of Benefits of Partial Source Removal (PDF) (1 pp, 27 KB)Factsheet (PDF) (2 pp, 130 KB) Contact: Lynn Wood

Field-scale research has demonstrated that a high percentage of nonaqueous-phase liquid (NAPL) mass can be rapidly depleted within source zones by using aggressive in situ remedial technologies, such as thermal treatment or cosolvent flushing. Even with these aggressive technologies, however, the efficiency of NAPL depletion often decays exponentially as NAPL mass is removed from the source; complete NAPL removal may not be technically or economically feasible. The uncertainty of restoration at sites where complete DNAPL depletion cannot be obtained is a key issue and EPA scientists have focused research on the use of a mass flux-based site management approach to assess NAPL source-zone treatment benefits.

Selected Products

Huang, J., M. Goltz, A. Demond, and D. Ayral. (2009). “Transport of Organic Solutes in Clay Formations (PDF)” (19 pp, 496 KB) Presentation, American Geophysical Union 2009 Fall Meeting, San Francisco, California, December 14–18.

Flux-Based Site Management Workshop. (2008). International Conference and Training Triad Investigations, New Approaches, and Innovative Strategies. University of Massachusetts–Amherst. Presentations:

Wood, L. Flux-Based Site Management (PDF) (9 pp, 824 KB)
Crumbling, D. Welcoming Innovation Through the Triad Approach (PDF) (21 pp, 948 KB)
Rao, S. Flux-Based DNAPL Site Assessment and Remediation: Overview of Concepts (PDF) (30 pp, 1.52 MB)
Falta, R.W. Flux-Based Remedial Design and Assessment Tools (PDF) (43 pp, 1.17 MB)
Brooks, M. Mass Flux Field Measurement Techniques (PDF) (28 pp, 908 KB)
Rao, S. Flux-Based DNAPL Site Remediation: Field Case Studies (PDF) (31 pp, 2.2 KB)

Remediation Evaluation Model for Chlorinated Solvents (REMChlor) (2008). Software.

Wood, A.L. and C.G. Enfield. Enhanced Source Removal (ZIP) (133 MB) (EPA/600/C-99/002) September 1999

Complete list of products associated with Aquifer Restoration by Enhanced Source Removal Project (ER-368) (PDF) (25 pp, 74 KB)

Complete list of products associated with Impacts of DNAPL Source Zone Treatment: Experimental and Modeling Assessment of Benefits of Partial Source Removal Project (ER-1295) (PDF) (9 pp, 30 KB)

Selected References

Goltz, M.N., M.E. Close, H. Yoon, J. Huang, M.J. Flintoft, S.J. Kim, and C. Enfield. (2009). "Validation of Two Innovative Methods to Measure Contaminant Mass Flux in Ground Water.” J. Contaminant Hydrology, 106: 51–61.

Brooks, M.C., A.L. Wood, M.D. Annable, K. Hatfield, J. Cho, C. Holbert, P.S.C. Rao, C.G. Enfield, K. Lynch, and R.E. Smith. (2008). “Changes in Contaminant Mass Discharge From DNAPL Source Mass Depletion: Evaluation at Two Field Sites.” Journal of Contaminant Hydrology, 102, 1-2:140–153.

Bob, M.M., M.C. Brooks, S.C. Mravik, and A.L. Wood. (2007). “A Modified Light Transmission Visualization Method for DNAPL Saturation Measurements in 2-D Models.” Advances inWater Resources, 31, 5: 727–742.

Enfield, C.G., A.L. Wood, F.P. Espinoza, M.C. Brooks, M.D. Annable, and P.S.C. Rao. (2005). “Design of Aquifer Remediation Systems: (1) Describing Hydraulic Structure and NAPL Architecture Using Tracers.” Journal of Contaminant Hydrology, 81, 1-4: 125–147.

Wood, A.L., C.G. Enfield, F.P. Espinoza, M. Annable, M.C. Brooks, P.S.C. Rao, D. Sabatini, and R. Knox. (2005). “Design of Aquifer Remediation Systems: (2) Estimating Site-Specific Performance and Benefits of Partial Source Removal.” Journal of Contaminant Hydrology, 81, 1-4: 148–166.

Mravik, S.C., R.K. Sillan, A.L. Wood, and G.W. Sewell. (2003). “Field Evaluation of the Solvent Extraction Residual Biotreatment Technology." Environmental Science and Technology, 37: 5040–5049.

Kavanaugh, M.C., P.S.C. Rao, and A.L. Wood. The DNAPL Remediation Challenge: Is There a Case for Source Depletion? (PDF) (129 pp, 1.1 MB) (EPA/600/R-03/143) December 2003 | Abstract

Contact

Michael Brooks
Environmental Engineer
580-436-8982

Junqi Huang
Hydrologist
580-436-8915

Lynn Wood
Soil Scientist
580-436-8552

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