EPA542-K-94-007

April 1995

In Situ Remediation Technology:

Electrokinetics

U.S. Environmental Protection Agency

Office of Solid Waste and Emergency Response

Technology Innovation Office

Washington, DC 20460
Acknowledgements

The authors would like to thank all the researchers and technology developers described in this report for

their assistance in its preparation. We especially would like to thank Randy A. Parker for reviewing the

draft document and making valuable suggestions for improvement.

For more information about this project, contact:

Rich Steimle

U.S. Environmental Protection Agency (5102W)

Technology Innovation Office

401 M Street, SW

Washington, DC 20460

703-308-8846

Notice

This material has been funded by the United States Environmental Protection Agency under contract

number 68-W2-0004. Mention of trade names or commercial products does not constitute endorsement or

recommendation for use.
i

Foreword

The purpose of this document is to describe recent field demonstrations, commercial applications, and

research on technologies that either treat soil and ground water in place or increase the solubility and

mobility of contaminants to improve their removal by pump-and-treat remediation. It is hoped that this

information will allow more regular consideration of new, less costly, and more effective technologies to

address the problems associated with hazardous waste sites and petroleum contamination.

This document is one in a series of reports on demonstrations and applications of in situ treatment

technologies. To order other documents in the series, contact the National Center for Environmental

Publications and Information at (513) 489-8190 or fax your request to NCEPI at (513) 489-8695. Refer to

the document numbers below when ordering.

EPA542-K-94-003 Surfactant Enhancements

EPA542-K-94-004 Treatment Walls

EPA542-K-94-005 Hydrofracturing/Pneumatic Fracturing

EPA542-K-94-006 Cosolvents

EPA542-K-94-007 Electrokinetics

EPA542-K-94-009 Thermal Enhancements

 ______________________________________ 

 Walter W. Kovalick, Jr., Ph.D.

Director, Technology Innovation Office
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iii

Contents

Introduction ....................................................................... 1

Purpose and Process .................................................... 1

Technology Needs ...................................................... 1

Technology Descriptions ................................................. 1

Ongoing and Future Demonstrations .................................................... 2

Isotron Corporation ..................................................... 2

Isotron Corporation ..................................................... 3

In Situ Remediation Technology Consortium ................................. 3

Electro-KleanTM Electrical Separation ...................................... 4

Sandia National Laboratories and Sat-Unsat, Inc. .............................. 5

Completed Commercial Applications ................................................... 7

Environment & Technology Services ....................................... 7

Current Research ................................................................... 8

Argonne National Laboratory ............................................. 8

Louisiana State University and Electrokinetics, Inc. ............................ 8

Electro-Petroleum, Inc. and Lehigh University . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Lehigh University . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Massachusetts Institute of Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Sandia National Laboratories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Texas A&M University . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

University of Massachusetts Lowell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

West Virginia University . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

General References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Abbreviations

BTEX = Benzene, Ethylbenzene, Toluene, Xylene

CERCLA = Comprehensive Environmental Response, Compensation, and Liability Act

DNAPL = Dense Non-Aqueous Phase Liquid

DOE = Department of Energy

PAH = Poly-Aromatic Hydrocarbon

PCE = Tetrachloroethylene

RCRA = Resource Conservation and Recovery Act

SITE = Superfund Innovative Technology Evaluation Program

SVE = Soil Vapor Extraction

SVOC = Semi-Volatile Organic Compound

TCA = 1,1,1-Trichloroethane

TCE = Trichloroethylene

TPH = Total Petroleum Hydrocarbon

VOC = Volatile Organic Compound
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1

Introduction

Purpose and Process

The purpose of this document is to describe demonstrations, field applications, and research on

electrokinetics for remediating contaminated soils and ground water at waste disposal and spill sites. 

Information for this report came from computerized databases such as the Dialog Information Services and

the Environmental Protection Agency's (EPA) Vendor Information System for Innovative Treatment

Technologies (VISITT) and Alternative Treatment Technologies Information Center (ATTIC). Additional

materials were obtained from publications such as the Hazardous Substance Research Center Annual

Reports, Superfund Innovative Technology Evaluation Technology Profiles and Department of Energy's

Office of Technology Development Program Summary as well as conference summaries, proceedings and

compendiums. Personal interviews and discussions with representatives of other federal agencies,

academic research centers, and hazardous waste remediation consulting firms provided supplementary

information.

Technology Needs

Although clay and silt tend to sequester large quantities of organic and inorganic contaminants, they are

resistant to remediation with traditional technologies because of their low hydraulic conductivities.

Recently, attention has focused on developing in situ electrokinetic techniques for the treatment of low

permeable soils contaminated with heavy metals, radionuclides, and selected organic pollutants. Although

electrokinetics has been used for decades in the oil recovery industry and to remove water from soils, in

situ applications of electrokinetics to remediate contaminated soil is new.

Technology Descriptions

Electrokinetics is a process that separates and extracts heavy metals, radionuclides, and organic

contaminants from saturated or unsaturated soils, sludges, and sediments. A low intensity direct current is

applied across electrode pairs that have been implanted in the ground on each side of the contaminated soil

mass. The electrical current causes electroosmosis and ion migration, which move the aqueous phase

contaminants in the subsurface from one electrode to the other. Contaminants in the aqueous phase or

contaminants desorbed from the soil surface are transported towards respective electrodes depending on

their charge. The contaminants may then be extracted to a recovery system or deposited at the electrode.

Surfactants and complexing agents can be used to increase solubility and assist in the movement of the

contaminant. Also, reagents may be introduced at the electrodes to enhance contaminant removal rates. 

The following pages contain descriptions of completed, on-going, and future demonstrations and current

research on electrokinetics in the United States. Electrokinetics is being used commercially in Europe to

remove heavy metal contaminants such as uranium, mercury, and metal mixtures.
2

Ongoing and Future Demonstrations

Old TNX Basin, Savannah River Site, South Carolina

Isotron Corporation

Electrokinetic Remediation

Description of Demonstration: The purpose of this demonstration is to remediate mercury contamination

in unsaturated soil consisting primarily of sand and kaolinite. Isotron Corporation is using an Electrosorb®

process with a patented cylinder to control buffering conditions in situ and an ion exchange polymer

matrix called Isolock® to trap metal ions. 

Wastes Treated: Mercury, lead, chrome

Status: This ongoing demonstration involving Isotron Corporation and Westinghouse Savannah River

Company is supported by the Department of Energy's Office of Technology Development. 

Demonstration Results: Although mercury is the target contaminant in this demonstration, preliminary

results indicate that at the 5 ppm mercury concentrations found at the site and other conditions, mercury

will be difficult to remediate in the Basin. However, the process is showing good results on lead and

chrome in the Basin.

Contacts:

Henry L. Lomasney

Isotron Corporation

13152 Chef Menteur Hwy

New Orleans, LA 70129

504-254-4624

Fax: 504-254-5172

Jane P. Bibler

Westinghouse Savannah River Company

803-725-5276

References:

Bibler, J.P.; Meaker, T.F.; and O'Steen, A.B. Electrokinetic Migration Studies on Removal of Chromium

and Uranyl Ions from 904-A Trench Soil. U.S. Department of Energy, WSCR-RP-92-1207. NTIS #:

DE93005074, 1992.
3

Oak Ridge K-25 Facility, Tennessee

Isotron Corporation

Electrokinetic Extraction

Description of Demonstration: The objective is to demonstrate the effectiveness of electrokinetics to

move and capture uranium and organic contaminants in soil. The process involves the application of a

direct current across the soil and patented system to capture the radionuclide.

Wastes Treated: Uranium and organic contaminants

Status: A pilot-scale demonstration, supported by the Department of Energy's Office of Technology

Development, is underway. Laboratory tests completed in 1994 using site soil showed that the process

could move and capture uranium.

Demonstration Results: None.

Contact:

Henry L. Lomasney

Isotron Corporation

13152 Chef Menteur Highway

New Orleans, LA 70129

504-254-4624

Fax: 504-254-5172

References:

U.S. DOE. In Situ Remediation Integrated Program: Technology Summary. U.S. Department of Energy,

Office of Environmental Management, Office of Technology Development, 1994.

DOE Gaseous Diffusion Plant, Paducah, Kentucky

In Situ Remediation Technology Consortium

Description of Demonstration: The demonstration will test the ability of an integrated technology to treat

TCE in clay. Highly permeable subsurface sorption zones will be created in a vertical configuration by

hydraulic fracturing or similar technology followed by the introduction of certain sorbents. The

electrodes, placed vertically on either side of the contaminant plume, will flush contaminants by electroosmotic flow into the sorption zones containing certain sorbents. (Electrodes and degradation zones may

be constructed horizontally or vertically depending on the site and contaminant characteristics.)

Wastes Treated: TCE

Status: Preliminary field trials began in the summer 1994, and in November 1994 CDM Federal Programs

Corporation installed field demonstration equipment. Bench and pilot scale experiments will be conducted

in 1994-1995, and field demonstrations of the full process is planned for 1995-1996. Integrated in situ

remediation technology is being developed by a consortium consisting of Monsanto with its trademark
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process Lasagna,TM E.I. DuPont de Nemours & Co., and General Electric with participation from the U.S.

EPA and U.S. DOE. 

Demonstration Results: None.

Contacts:

Sa Ho or B. Mason Hughes

Environmental Sciences Center

Monsanto Company

St. Louis, MO 63167

314-694-5179/314-694-1466

Fax: 314-694-1531

Steven J. Bossart

U.S. Department of Energy

304-285-4643

Fax: 304-285-4403

U.S. Army Waterways Experiment Station, Baton Rouge, Louisiana

Electrokinetics, Inc.

Electro-KleanTM Electrical Separation

Description of Demonstration: Electro-KleanTM is an in situ process that removes or captures heavy

metals, radionuclides, and selected volatile organic pollutants from saturated or unsaturated sands, silts,

fine-grained clays, and sediments. Electrodes are placed on each side of the contaminated soil mass, and

direct current is applied. Conditioning fluids may be added or circulated at the electrodes to enhance the

electrochemistry of the process. The concurrent mobility of the ions and pore fluid decontaminates the soil

mass. Contaminants are electroplated on the electrodes or separated in a post-treatment unit. 

Wastes Treated: Lead

Status: The field demonstration of the in situ pilot-scale Electro-KleanTM process for removing lead at a

U.S. Army firing range is expected to be initiated by the Spring of 1995. Electrokinetics, Inc. and the U.S.

Army are preparing construction guidelines, and design and analysis processes for the demonstration.

Numerous bench-scale and pilot-scale laboratory studies involving the feasibility of removing lead,

uranium, and thorium from kaolinite have been completed under the SITE Emerging Technology

Program. Schemes which enhance transport and extraction of substances have been developed by

Electrokinetics, Inc., in collaboration with and support from the U.S. Army. Pilot-scale studies with 1.5

ton samples of a soil retrieved from the Army firing range and contaminated with lead leached from

bullets are ongoing. Electrokinetics, Inc.'s process was developed in conjunction with Louisiana Business

and Technology Center at the Louisiana State University.

Demonstration Results: None.
5

Contact:

Robert Marks, General Manager

Electrokinetics, Inc.

Louisiana Business and Technology Center

Louisiana State University, Suite 155

South Stadium Drive

Baton Rouge, Louisiana 70803-6100

504-388-3992

Fax: 504-388-3928

References:

Acar, Y.B.; Puppala, S.; Marks, R.; Gale, R.J.; and Bricka, M. Investigation of Selected Enhancement

Techniques in Electrokinetic Remediation. Report presented to US Army Waterways Experiment Station,

Electrokinetics Inc., Baton Rouge, Louisiana, 1994, p 160.

U.S. Environmental Protection Agency, Office of Emergency and Remedial Response. Superfund

Engineering Issue: Treatment of Lead-Contaminated Soils. EPA/540/2-91/009. April, 1991. 

U.S. Environmental Protection Agency, Office of Research and Development. Superfund Innovative

Technology Evaluation Program Technology Profiles. 7th ed. EPA/540/R-94/526. November, 1994. p

262-263.

U.S. Patent and Trademark Office. Electrochemical Decontamination of Soils or Slurries. Patent

#5,137,608, August 11, 1992.

Sandia National Laboratories Chemical Waste Landfill

Sandia National Laboratories and Sat-Unsat, Inc.

In Situ Electrokinetic Extraction

Description of Demonstration: Three to five electrode pairs, supplied with water and neutralization

chemicals, will be used to treat chromium-contaminated soil over a 120-day period. Between 25 and 120

kilograms of chromium are expected to be removed from 700 to 1,000 cubic feet of soil. Soluble

chromium concentrations range from 25 (background) to 10,000 ppm with the upper limit at 15 feet below

ground surface. Contaminants arriving at the electrodes will be removed using a vacuum system. 

Wastes Treated: Chromium

Status: Sandia National Laboratories has requested that their planned field demonstration in the unlined

chromic acid pit at the landfill be conducted under the SITE program. Research and demonstrations at the

Sandia National Laboratories are supported by the U.S. Department of Energy.

Demonstration Results: None.
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Contact:

Eric R. Lindgren

Sandia National Laboratory

P.O. Box 5800, Mail Stop 0727

Albuquerque, NM 87185

505-844-3820

Fax: 505-844-1480

References:

Lindgren, E.R. and Mattson, E.D. SITE Demonstration Program Proposal: In Situ Electrokinetic

Extraction System. Sandia National Laboratories, New Mexico.
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Completed Commercial Applications

An Underground Storage Tank Spill

Environment & Technology Services

Electrokinetic Enhancement

Description of Demonstration: Direct current was applied through 56 electrodes installed in the upper

clay layer of this 2,400 square foot gasoline contaminated site to move contaminants and water down 15

feet into dense cemented conglomerate sandstone where contaminants were removed by bioventing.

Electrolysis of some water molecules, resulting from the electrical gradient, was thought to have produced

hydroxyl ions that promoted oxidation of the contaminants.

Wastes Treated: BTEX

Status: Completed.

Demonstration Results: Bioventing, enhanced by electrokinetics, reportedly reduced gasoline levels of

100-2,200 ppm to well below the target of 100 ppm after about 90 days at a cost of about $50/ton.

Contact:

Walter Loo

Environmental & Technology Services

2081 15th Street

San Francisco, CA 94114

415-861-0810

Fax: 415-861-3269

References:

“Firm Employs Electrokinetics to Assist Subsurface Cleanup” HazTECH News. 9(24) p 185 (1994).
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Current Research

Electrokinetic Soil Remediation

Argonne National Laboratory

Description of Research: Investigators at Argonne National Laboratory are studying the effects of

various system parameters such as temperature and applied voltage on the complex subsurface phenomena

that occur during electrokinetics soil remediation. Initial studies have focussed on the effect of temperature

on the removal/extraction of potassium dichromate from kaolinite soil.

Wastes Treated: Potassium dichromate

Contact:

Theodore R. Krause

Argonne National Laboratory

9700 South Cass Avenue

Argonne, Illinois 60439

708-252-4356

Fax: 708-252-5912

References:

Krause, T.R. and Tarman, B. “Preliminary Results from the Investigation of Thermal Effects in

Electrokinetics Soil Remediation.” ANL/CMT/CP-79321. Conference Proceedings: Annual American

Chemical Society Industrial and Engineering Chemistry Division Special Symposium on Emerging

Technologies for Hazardous Waste Management, Atlanta Georgia. September 27-29, 1993. U.S.

Department of Energy.

Electrokinetic Remediation

Louisiana State University and Electrokinetics, Inc.

Description of Research: The primary goal of past and ongoing research at Louisiana State University

(LSU) is to explore, investigate, and use multi-species transport mechanisms in soils under electrical fields

for developing techniques to remediate soils from inorganic and organic substances and radionuclides. The

mission of Electrokinetics, Inc. is to translate the scientific knowledge developed by LSU and other

researchers into practice by carrying out the essential developmental work in deployment and

commercialization of the promising technologies. 

Bench-scale studies are conducted at LSU to evaluate the feasibility of removing lead, chromium,

cadmium, zinc, uranium, radium, and thorium from spiked and natural contaminated soils. Bench-scale

studies also have been carried out to investigate the feasibility of transporting phenol, hexachlorobutadiene

and trinitrotoluene (TNT). Both clays/granular soils and spiked/natural specimens have been used in

testing. The feasibility and cost-effectiveness of electrokinetic remediation in extracting some of these

inorganic species have been demonstrated. The efficiency of extraction relies upon several factors such as

the type of species, their solubility chemistry in the specific soil, their electrical charge, their concentration

relative to other species, their location and form in the soil, available counter ions in the soil, type of soil,
9

availability of organic matter in the soil, processing parameters used, and the type of conditioning and

enhancement scheme employed in the electrokinetic remediation process. Studies at LSU indicate that

polar species such as phenol may be removed under electrical fields below their solubility limit, but

removal of nonpolar species such as hexachlorobutadiene and TNT under electrical fields is possible only

if aqueous surfactant solutions are used in order to increase the solubility of the organic species and to

form charged micelles.

Pilot-scale studies have been conducted under a cooperative agreement between the U.S. EPA and

Electrokinetics, Inc. of Baton Rouge. The efficiency and feasibility of removing lead from spiked one ton

specimens of clay have been demonstrated in three separate pilot-scale tests. In research sponsored by the

U.S. EPA, researchers at LSU have developed a theoretical model for multi-species transport in soils

under electrical fields. The numerical implementation of the model has been verified through correlations

with the results of the pilot-scale studies. 

LSU researchers and Electrokinetics Inc. personnel, in a collaborative effort with the Department of

Energy (DOE) and the U.S. EPA also have initiated a research and development program which aims to

deploy multi-species transport processes under electrical fields in injection of process additives and

nutrients for effective in situ bioremediation of organic species. Bench and pilot-scale studies investigating

transport rates of selected species in heterogenous soil conditions are ongoing. Pilot-scale studies and field

demonstration studies are planned.

Wastes Treated: Heavy metals, radionuclides, organics.

Contact:

Yalcin Acar

Louisiana State University

Department of Civil and Environmental Engineering

Center for Engineering and Business Administration

Baton Rouge, LA 70803-6100

504-388-8638

Fax: 504-388-8652

References:

Acar, Y.B. “Electrokinetic Soil Processing.” In Handbook on Approaches for the Remediation of Federal

Facility Sites Contaminated with Explosive or Radioactive Wastes. U.S. Environmental Protection

Agency, Office and Research and Development, EPA/625/R-93/013, p 77-83.

Acar, Y.B. “Electrokinetic Soil Processing; A Review of the State of the Art.” Conference Proceedings:

1992 ASCE Specialty Conference on Grouting, Soil Improvement and Geosynthetics. Geotechnical

Publication, 30 (2), p 1420-1432.

Acar Y.B. and Alshawabkeh, A. “Electrokinetic Remediation: An Assessment of Principles.” Conference

Proceedings: EPRI Electrokinetics Workshop, 1994, Palo Alto, CA., EPRI TR-104170, p 49-54.

Acar, Y.B. and Alshawabkeh, A. “Modeling Transport of Species Under an Electric Field”. Conference

Proceedings: XIII International Conference on Soil Mechanics and Foundation Engineering, Oxford and

IBH Publishing Co. Pvt. Ltd., New Delhi, India, 2: 662-669.

Acar, Y.B. and Alshawabkeh, A. “Principles of Electrokinetic Remediation.” Environmental Science and

Technology, 27 (13), 1993, p 2638-2647.
10

Acar, Y.B. and Gale, R. J. Electrochemical Decontamination of Soils and Slurries. US Patent No.

5,137,608, Commissioner of Patents and Trademarks, Washington, D.C., August 11, 1992.

Acar, Y.B. and Hamed, J. “Electrokinetic Soil Processing in Remediation/Treatment; Synthesis of

Available Data.” Bulletin of the Transportation Research Board, National Academy of Sciences,

Geotechnical Engineering 1312, 1991, p 152-161.

Acar, Y.B.; Alshawabkeh, A.N.; Gale, R.J.; Puppala, S.; Parker, R.; Bricka, M. “Electrokinetic Soil

Remediation: Technology Status.” Conference Proceedings: 21st Annual RREL Hazardous Waste

Research Symposium, Abstract Proceedings. U.S. Environmental Protection Agency, 1995 (in press).

Acar, Y.B.; Gale, R.J.; Alshawabkeh, A.; Marks, R.E.; Puppala, S.; Bricka, M.; and Parker, R.

“Electrokinetic Remediation: Basics and Technology Status.” Journal of Hazardous Materials, 40 (3),

1995, p 117-137.

Acar, Y.B.; Puppala, S.; Marks, R.; Gale R.J. and Bricka, M. An Investigation of Selected Enhancement

Techniques in Electrokinetic Remediation. Report presented to US Army Waterways Experiment Station,

Electrokinetics Inc., Baton Rouge, Louisiana, 1994, 160p.

Acar, Y.B.; Hamed, J.; Alshawabkeh, A.; and Gale R.J. “Cadmium Removal From Saturated Kaolinite by

Electrokinetics.” Géotechnique, 44 (3), 1994, p 239-254.

Acar, Y.B.; Alshawabkeh, A.N.; and Gale R.J. 1994. “Electrokinetic Soil Remediation: A Pilot-Scale

Study.” Conference Proceedings: 20th Annual RREL Hazardous Waste Research Symposium, Abstract

Proceedings, 1994, U.S. Environmental Protection Agency, EPA/600/R-94/01154, p 168-172.

Acar, Y.B.; Alshawabkeh, A. and Gale, R.J. “Fundamental Aspects of Extracting Species from Soils by

Electrokinetics.” Journal of Waste Management, 12 (3), 1993, p 1410-1421.

Acar, Y.B.; Gale, R.J.; Ugaz, A.; and Marks, R. “Feasibility of Removing Uranyl, Thorium and Radium

from Kaolinite by Electrokinetics.” Conference Proceedings: 19th Annual RREL Hazardous Waste

Research Symposium, Abstract Proceedings, 1993, U.S. Environmental Protection Agency, EPA/600/R93/040, p 161-165.

Acar, Y.B.; Li, H. and Gale R.J. “Phenol Removal from Kaolinite by Electrokinetics.” Journal of

Geotechnical Engineering, 118 (11), 1992, 1837-1852.

Acar, Y.B.; Gale, R.J.; Ugaz, A.; Puppala, S.; Leonard, C. Feasibility of Removing Uranium, Thorium and

Radium from Kaolinite by Electrochemical Soil Processing. EK-BR-009-0292, Final Report-Phase I of

EK-EPA Cooperative Agreement CR816828-01-0, Electrokinetics Inc., Baton Rouge, Louisiana, 1992,

243p.

Acar, Y.B.; Gale, R.J.; and Putnam, G.; Hamed, J. and Wong, R. “Electrochemical Processing of Soils:

Theory of pH Gradient Development by Diffusion and Linear Convection.” Journal of Environmental

Science and Health, 25 (6), 1990, p 687-714.

Acar, Y.B.; Gale, R.J.; Putnam, G.; and Hamed, J. “Electrochemical Processing of Soils: Its Potential Use

in Environmental Geotechnology and Significance of pH Gradients.” Conference Proceedings: 2nd

International Symposium on Environmental Geotechnology, Shanghai, China, 1989. Envo Publishing,

Bethlehem, PA, p 25-38.
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Alshawabkeh, A. Theoretical and Experimental Modeling of Removing Species from Soils by

Electrokinetics. PhD Thesis, Louisiana State University and Agricultural and Mechanical College, Baton

Rouge, Louisiana, 1994, 375p.

Alshawabkeh, A. and Acar, Y.B. “Electrokinetic Remediation: I. Pilot-Scale Study; II. Theory”. Journal

of Geotechnical Engineering, 1995, (in press).

Alshawabkeh, A., Acar Y.B. “Electrokinetic Remediation: Modeling the Process.” Conference

Proceedings: 207th Annual Meeting of the American Chemical Society, San Diego, CA, 1994.

Alshawabkeh, A. and Acar, Y.B. “Removal of Contaminants from Soils by Electrokinetics: A Theoretical

Treatise.” Journal of Environmental Science and Health, 27 (7), 1992, p 1835-1861.

Hamed, J. Decontamination of Soil Using Electro-Osmosis. PhD Thesis, Louisiana State University and

Agricultural and Mechanical College, Baton Rouge, LA, 1990.

Hamed, J.; Acar, Y.B.; and Gale, R.J. “Pb(II) Removal from Kaolinite Using Electrokinetics.” Journal of

Geotechnical Engineering, 112 (2), 1991, p 241-271.

Li, H.L.; Gale, R.J. and Acar; Y.B. “Soil Decontamination Using Electrokinetic Processing.” In:

Environmental Oriented Electrochemistry, C.A.C. Sequeira (Editor), Elsevier Science Publishers, 1994.

Marks, R.E.; Acar, Y.B.; Gale, R.J. 1994. “In Situ Remediation of Contaminated Soils Containing

Hazardous Mixed Wastes by Bio-Electrokinetic Remediation and Other Competitive Technologies.” In:

Remediation of Hazardous Waste Contaminated Soils. Donald L. Wise and Debra J. Trantolo (eds.),

Marcel Dekker Inc., 1994, Chapter 18, p 405-436.

Puppala, S.K.; Marks, R.E.; Acar, Y.B.; Gale, R.J. “Enhancement Techniques in Electrokinetic

Remediation.” Conference Proceedings. I&EC Special Symposium, the American Chemical Society,

Atlanta, GA, 1994, p 1192-1195.

Tran, N.K. and Gale, R.J. “Micellar Electrokinetic Soil Decontamination.” Conference Proceedings:

Environmental Aspects of Electrochemistry and Photoelectrochemistry. May 16-21, 1993, Honolulu, HI.

Ugaz, A.; Puppala, S.; Gale, R.J.; and Acar, Y.B. “Complicating Features of Electrokinetic Remediation

of Soils and Slurries: Saturation Effects and the Role of the Cathode Electrolysis.” Communications in

Chemical Engineering, December 1994.
12

In Situ Electrokinetic Soil Processing

Electro-Petroleum, Inc. and Lehigh University

Description of Research: Laboratory studies conducted by Electro-Petroleum, Inc. and Lehigh University

have shown mobilization of 15 metals and 6 organic compounds in five soil matrices with an electrokinetic process developed by Electro-Petroleum, Inc. (Some of the research has been conducted under two

contracts through the Argonne and Sandia National Laboratories.) The electrokinetic process can treat

soils, sludges, and sediments contaminated with heavy metals and organic hydrocarbons but works best on

clay-type soils with low hydraulic permeability. Electrokinetic permeabilities for aqueous systems in clays

have been demonstrated to be up to one thousand times greater than normal hydraulic permeabilities, and

some heavy metals have exhibited removal efficiencies of up to 100%. Based on laboratory-scale

experiments, Electro-Petroleum, Inc. estimates the cost of in situ remediation should be approximately $50

per cubic yard. 

The only field testing of Electro-Petroleum, Inc.'s electrokinetic process has been under confidentiality

agreements in oil fields. Two full-scale systems are in the design phase of development. 

Wastes Treated: Heavy metals, volatile and semivolatile organic compounds, solvents, BTEX,

radioactive metals, inorganic cyanides

Contact:

J. Kenneth Wittle

Electro-Petroleum, Inc.

Suite 1118

996 Old Eagle School Road

Wayne, PA 19087

610-687-9070

Fax: 610-964-8570

References:

Khan, L.I.; Pamukcu, S.; Wittle, J.K.; and Titus, C.H. “Electrokinetic Treatment of Contaminated Soil.”

AIChE Meeting, Pittsburgh, PA, August 1991.

Pamukcu, S. and Wittle, J.K. “Electrokinetic Removal of Selected Heavy Metals from Soil.”

Environmental Progress, 11 (3), 1992, p 241-250.

Pamukcu, S. and Wittle, J.K. “Electrokinetically Enhanced Decontamination of Soils, Sludges, and

Groundwater.” Fine Particle Society Symposium, Chicago, Illinois, August 1993.

Pamukcu, S. and Wittle, J.K. “Electrokinetics for Removal of Low-Level Radioactivity from Soil.”

Fourteenth Annual Department of Energy Low-Level Radioactive Waste Management Conference.

Phoenix, AZ, November 18-20, 1992, Conf-921137-Proc, p 256-278.

Pamukcu, S. and Wittle, J.K. “Electrokinetics for Use as an Innovative Insitu Remediation Process.” I&EC

Special Symposium, American Chemical Society, Atlanta, GA, September 1994.
13

Pamukcu, S.; Newhart, G.; Wittle, J.K. “Electrokinetically Enhanced Transport of Surrogate

Radionuclides and Mixed Organic Contaminants in Soil.” I&EC Special Symposium, American Chemical

Society, Atlanta, GA, September 1993.

Pamukcu, S.; Newhart, G.; Wittle, J.K. “Use of Electrokinetics to Control the Mitigation of Heavy Metals

from Landfill Sites.” Green '93, Bolton, England, June 1993.

Pamukcu, S.; Wittle, J.K.; and Titus, C.H. “Electrokinetics: Emerging Technology for In Situ Soil

Remediation.” Conference Proceedings: Hazardous Materials Control Research Institute Federal

Environmental Restoration Conference and Exhibition, Vienna, Virginia, April 15-17, 1992.

Wittle, J.K. and Pamukcu, S. Electrokinetic Treatment of Contaminated Soils, Sludges, and Lagoons.

Final Report. DOE/CH-9206. U.S. Department of Energy, Argonne National Laboratory, 1993.

Wittle, J.K. and Pamukcu, S. “Electrokinetics and Its Enhancement in In-Situ Soil Treatment of

Manufactured Gas Plant Wastes.” I&EC Special Symposium, American Chemical Society, Atlanta,

Georgia, September 1992.

Wittle, J.K.; Pamukcu, S.; and Reed, B. “Electrokinetic Removal of Inorganic Contaminants.” EPRI

Workshop on In Situ Electrochemical Soil and Water Remediation, Palo Alto, CA, February 1994. 

Electrokinetic Soil Processing

Lehigh University

Description of Research: The critical parameters of electroosmosis and flow enhancing ions have been

investigated in a series of laboratory experiments. The study demonstrated successful removal of 16

targeted PAH compounds from the soil (clay or granular) at a removal rate of 44 to 70% upon 2 to 9 pore

volumes of electroosmotic water flow through the soil specimens. In general, the degree of success of

decontamination by electrokinetic process appeared to be parameter specific; more dependent on the type

of the contaminant to be removed than the type of medium being decontaminated. Electroosmosis

appeared to be the dominant mechanism of transport when the contaminants present in the aqueous phase

were nonpolar or nonionic, neutral micelles or surface-coated colloids.

Investigations of clay or clay mixtures and a known concentration of a selected heavy metal salt solution

or an organic compound showed up to 99% heavy metal removal and high removal levels of some organic

compounds such as phenol, acetic acid, and O-nitrophenol. Transient pH change through the soil had an

effect on the metal movement as evidenced by accumulation of the metals at the discharge ends of the soil

specimens. The accumulation was attributed to the precipitation of the metals and increased cation

retention capacity of the clay in high pH environment at the cathode end. In general, precipitation, reduced

mobility, and reduced dissociation of the ionic species as they encountered areas of higher ionic

concentration in their path of migration resulted in the accumulation of the metals at the discharge ends of

the soil specimens.

Wastes Treated: Coal tar, radionuclides, priority heavy metals
14

Contact:

Sibel Pamukcu

Lehigh University

Department of Civil and Environmental Engineering

Fritz Engineering Laboratory

13 East Packer Ave.

Bethlehem, PA 18015

610-758-3220

Fax: 610-758-4522

E-Mail: SP01@Lehigh.edu

References:

Khan, L.I. Study of Electroosmosis in Soil: A Modified Theory and Its Application in Soil

Decontamination. Dissertation Abstracts International, 1992, 52(12-B), p 6546.

Khan, L.I. and Pamukcu, S. “Validity of Electro-Osmosis for Soil Decontamination.” Conference

Proceedings of the 1989 Specialty Conference, Austin, TX, July 10-12, 1989, p 563-570. 

Pamukcu, S. Electrokinetic Removal of Coal Tar Constituents from Contaminated Soils. Electric Power

Research Institute Report, EPRI-TR-103320, Palo Alto, CA, 1994. 92p.

Pamukcu, S.; Khan, L.I.; and Fang, H.Y. “Zinc Detoxification of Soils by Electro-Osmosis.”

Transportation Research Record, 1288, 1990, p 41-46.

Pamukcu, S.; Newhart, G.; and Wittle, J.K. “Use of Electrokinetics to Control the Migration of Heavy

Metals from Landfill Sites.” Proceedings of Green '93, an International Symposium on Geotechnics

Related to the Environment, Balkema Publ., Netherlands, 1995.

Pamukcu, S. and Wittle, J.K. “Electrokinetic Removal of Selected Heavy Metals from Soil.”

Environmental Progress, 11 (3), 1992, p 241-250.

Pamukcu, S. and Wittle, J.K. “Electrokinetically Enhanced Insitu Soil Decontamination.” in Remediation

of Hazardous Waste Contaminated Soils, Chapter 13. Wise and Trantolo (eds.). New York: Marcel

Dekker, 1993. p 245-298.

Pamukcu, S. and Wittle, J.K. “Electrokinetics for Removal of Low-Level Radioactivity from Soil.”

Fourteenth Annual Department of Energy Low-Level Radioactive Waste Management Conference.

Phoenix, AZ, November 18-20, 1992, Conf-921137-Proc, p 256-278.

Whittle, J.K. and Pamukcu, S. Electrokinetic Treatment of Contaminated Soils, Sludges, and Lagoons.

U.S. Department of Energy, Argonne National Laboratories. DOE/CH-9206, No. 02112406, 1993. 65p.
15

Electroremediation

Massachusetts Institute of Technology

Description of Research: The purpose of the research is to develop and verify a mathematical model that

can be used in identifying optimal operating conditions for electrokinetic decontamination of waste sites.

The model is intended to take into account the complex interaction of subsurface effects that occur

simultaneously when a direct current is applied in soil. Tests are being conducted in laboratory test cells to

identify the multiple parameters that influence the electrokinetic process and to verify the model.

Experimental results of up to 94% removal for some chemicals such as phenol or acetic acid and 98%

removal of heavy metals such as zinc in compacted kaolin were in good agreement with model predictions

when important parameters, such as electrode reactions and pH, were accounted for. This research, which

is sponsored by the U.S. Department of Energy, is expected to improve the efficiency and reduce the cost

of practical applications of the technology.

Wastes Treated: Heavy metals, organics

Contact:

Ronald F. Probstein

Massachusetts Institute of Technology

Department Mechanical Engineering

Cambridge, MA 02139

617-253-2240

Fax: 617-258-8559

References:

Shapiro, A.P. and R.F. Probstein. 1993. Removal of contaminants from saturated clay by electroosmosis.

Environ. Sci. Technology 27(2):283.

Hicks, R.E. and S. Tondorf. 1994. Electrorestoration of metal contaminated soils. Environ. Sci.

Technology 28(12):2203.

Jacobs, R.A., M.Z. Sengun, R.E. Hicks and R.F. Probstein. 1994. Model and experiments on soil

remediation by electric fields. J. Environ. Sci. Health A29(9):1933.

Probstein, R.F. and R.E. Hicks. 1993. Removal of contaminants from soils by electric fields. Science

260:498.
16

Electrokinetics

Sandia National Laboratories

Description of Research: The purpose of this research program is to develop an in situ electrokinetic

process for remediating unsaturated soils contaminated with heavy metals. The results of laboratory

electrokinetic studies on large anionic organic dyes in unsaturated soil (as low as about 25% saturation)

indicate that electrokinetics is a feasible alternative for remediating in situ anionic heavy metals like

chromate and uranium. In sandy soils with approximately 40 to 60% moisture saturation, the bench-scale

electrokinetic process removed 75 to 90% of initial chromium.

Wastes Treated: Chromium

Contact:

Eric R. Lindgren

Sandia National Laboratory

P.O. Box 5800, Mail Stop 0727

Albuquerque, NM 87185

505-844-3820

Fax: 505-844-1480

References:

Lindgren, E.R., M.W. Kozak and E.D. Mattson. 1991. Electrokinetic remediation of contaminated soils.

SAND-91-0726C. Conference Proceedings: Environmental Remediation '91 Conference, September 8-11,

1991. Pasco, Washington. U.S. Department of Energy. NTIS: DE91018683/XAB.

Lindgren, E.R., M.W. Kozak and E.D. Mattson. 1992. Electrokinetic remediation of anionic contaminants

from unsaturated soils. SNAD-92-0818C. Conference Proceedings: International Symposium on

Environmental Contamination, October 12-16. Budapest, Hungary. U.S. Department of Energy. NTIS:

DE93002479/XAB.

Lindgren, E.R., M.W. Kozak, E.D. Mattson. 1992. Electrokinetic remediation of unsaturated soils. SAND92-0817C. Conference Proceedings: Industrial and Engineering Chemistry Special Symposium of the

American Chemical Society, September 21-23, 1992. Atlanta, Georgia. U.S. Department of Energy. NTIS:

DE93000741/CAB.

Lindgren, E.R., R.R. Rao and B.A. Finlayson. 1993. Numerical simulation of electrokinetic phenomena.

Conference Proceedings: Annual American Chemical Society Industrial and Engineering Chemistry

Division Special Symposium on Emerging Technologies for Hazardous Waste Management, September

27-29, 1993. Atlanta Georgia. U.S. Department of Energy. 

Mattson, E.D. and E.R. Lindgren. 1993. Electrokinetic extraction of chromate from unsaturated soils.

SAND-93-7077C. Conference Proceedings: Annual American Chemical Society Industrial and

Engineering Chemistry Division Special Symposium on Emerging Technologies for Hazardous Waste

Management, September 27-29, 1993. Atlanta Georgia. U.S. Department of Energy. NTIS:

DE94002042/XAB.
17

Electrokinetic Extraction

Texas A&M University

Description of Research: Researchers formulated a coupled flow theory for the transport of fluid,

electricity, and contaminants under the combined influences of hydraulic, electrical, and chemical

gradients to describe the contaminant transport during the electrokinetic extraction process.

Electrochemical reactions associated with the processes and soil-contaminant interactions are also

included. A numerical model was developed to simulate the contaminant transport, electrochemical

reactions, and soil-contaminant interactions during the extraction processes. Bench scale experiments were

performed to evaluate the validity of the theory and numerical model.

Wastes Treated: Sodium chloride, lead nitrate, phenol, acetic acid

Contact:

Albert T. Yeung

Department of Civil Engineering

Texas A&M University

College Station, TX 77843-3136

409-845-2538

Fax: 409-845-6554

E-mail: ALYEUNG@tamu.edu

References:

Datla, S. and Yeung, A.T. “Subsurface Migration of Contaminants under the Coupled Influences of

Hydraulic, Electrical, and Chemical Gradients.” Proceedings of the 8th International Conference of the

International Association for Computer Methods and Advances in Geomechanics. Morgantown, West

Virginia, 1994, 2, p 1042, 1048.

Mitchell, J.K. and Yeung, A.T. “Electro-Kinetic Flow Barriers in Compacted Clay.” Geotechnical

Engineering, 1990, Transportation Research Record 1288, p 1-9.

Mitchell, J.K. and Yeung, A.T. Waste Containment and Cleanup Using Electro-Osmosis. Technical

Completion Report of Project W-699. University of California Water Resources Center, 1989.

Yeung, A.T. “Complicated Phenomena of Electro-Kinetic Extraction of Contaminants from Soil.”

Conference Proceedings: 207th American Chemical Society National Meeting, March 13-18, 1994. San

Diego, CA. Washington, DC: American Chemical Society, March 1994.

Yeung, A.T. “Coupled Flow Equations for Water, Electricity, and Ionic Contaminants through Clayey

Soils Under Hydraulic, Electrical, and Chemical Gradients.” Journal of Non-Equilibrium

Thermodynamics, 15 (3), 1990, p 247-267.

Yeung, A.T. “Electro-Kinetic Barrier to Contaminant Transport.” Proceedings of the International

Conference on Environmental Management: Geo-Water & Engineering Aspects. Wollongong, Australia,

1993, p 239-244.

Yeung, A.T. “Electro-Kinetic Flow Processes in Porous Media and Their Implications.” Advances in

Porous Media, 2, 1994, p 309-395.
18

Yeung, A.T. Enhancement of In-Situ Bioremediation of Contaminated Soil by Electrokinetics. Final

Research Completion Report Submitted to the Gulf Coast Hazardous Substance Research Center,

Beaumont, Texas, February 1995.

Yeung, A.T. “Environmental Engineering Applications of Electro-Kinetic Flow Processes: State-of-theArt.” Hong Kong Engineers. 21 (11), 1993, p 25-30.

Yeung, A.T. “Waste Containment Using Electro-Kinetics.” Proceedings of the International Symposium

on Geology and Confinement of Toxic Wastes. Montpellier, France, 1993, p 585-590.

Yeung, A.T. and Datla, S. “Fundamental Formulation of Electro-Kinetic Extraction of Contaminants from

Soil.” Canadian Geotechnical Journal, 1995 (in press).

Yeung, A.T.; Gopinath, S.; Menon, R.M.; Scott, T.B.; and Datla, S. “Electro-Kinetic Extraction of

Contaminants from Polluted Soil.” Waste Management, 13 (5-7), 1993, p 539.

Electrokinetics

University of Massachusetts Lowell

Description of Research: Researchers have been conducting laboratory and bench-scale research on the

effectiveness of electroosmosis for removing hydrocarbons and heavy metals from clay. Benzene, toluene,

TCE, and m-xylene—all of which have relatively high water solubilities—were more easily removed from

fine-grained soils than hexane and isooctane and other compounds with low water solubilities and high

distribution coefficients. Researchers also are studying the physical and chemical characteristics of

electroosmotic contaminant transport. The data are being used to gain insights into electroosmotic organic

contaminant displacement and how soil and pore water characteristics affect the process.

Wastes Treated: BTEX, hexane, isooctane, other hydrocarbons, and lead

Contact:

Clifford J. Bruell

University of Massachusetts Lowell

Civil Engineering Department

One University Avenue

Lowell, MA 01854

508-934-2280

Fax: 508-934-3052

References:

Bruell, C.J., B.A. Segall and M.T. Walsh. 1992. Electroosmotic removal of gasoline hydrocarbons and

TCE from clay. J. Environ. Engineering 118(1):68-83.

Segall, B.A. and C.J. Bruell. 1992. Electroosmotic contaminant-removal processes. J. Environ.

Engineering 118(1):84-100.
19

In Situ Electrokinetics

West Virginia University

Description of Research: The Department of Energy has sponsored laboratory and bench-scale studies on

the use of electrokinetics to remediate fine-grained soil contaminated with lead. The research included an

evaluation of the impact of initial conditions on the efficiency of electrokinetics to drive liquids and

contaminants through soil samples. An electrokinetic soil reactor designed to mimic in situ electrokinetic

flushing was applied to silt loam artificially contaminated with lead. Studies of the removal of lead from

soils indicate that the efficiency of lead removal is related to the flow of the acid front generated by the

positive electrode.

Wastes Treated: Lead

Contact:

Brian Reed

West Virginia University

Department of Civil and Environmental Engineering

647 Engineering Science Building

Morgantown, WV 26506

304-293-3031 x613

References:

Reed, B.E. and Berg, M.T. Removal of Contaminants from Fine-Grained Soils Using Electrokinetic

Flushing. Final Report. September 30, 1987-June 30, 1993. U.S. Department of Energy, National

Research Center for Coal and Energy, DOE/MC/24207-3532, 1993.
20

General References

Acar, Y.B., R.J. Gale, G. Putnam and J. Hamed. 1989. Electrochemical Processing of Soils: Its Potential

Use in Environmental Geotechnology and Significance of pH Gradients. Conference Proceedings: 2nd

International Symposium on Environmental Geotechnology, Shanghai, China, Envo Publishing,

Bethlehem, PA, 1:25-38.

Acar, Y.B., R.J. Gale, G. Putnam, J. Hamed and R. Wong. 1990. Electrochemical Processing of Soils:

Theory of pH Gradient Development by Diffusion and Linear Convection. J. Environmental Science and

Health, Part (A); Envir. Sci. and Engineering, 25(6):687-714.

Acar, Y.B. and J. Hamed. 1991. Electrokinetic Soil Processing in Remediation/Treatment; Synthesis of

Available Data. Bulletin of the Transportation Research, National Academy of Sciences, Geotechnical

Engineering 1312:152-161.

Acar, Y.B. 1992. Electrokinetic soil processing; a review of the state of the art. Conference Proceedings:

ASCE Specialty Conference on Grouting, Soil Improvement, and Geosynthetics. New Orleans, LA.

Getotechnical Publication 30(2):1420-1432. 

Acar, Y.B. and A. Alshawabkeh. 1993. Principles of Electrokinetic Remediation. Envir. Sci. Tech.

27(13):2638-2647.

Acar, Y.B. “Electrokinetic Soil Processing.” In: Handbook on Approaches for the Remediation of Federal

Facility Sites Contaminated with Explosive or Radioactive Wastes. U.S. Environmental Protection

Agency, Office and Research and Development, EPA/625/R-93/013, 1993, p 77-83.

Acar, Y.B., Alshawabkeh, A. and Gale, R.J. “Fundamental Aspects of Extracting Species from Soils by

Electrokinetics.” Journal of Waste Management, 12 (3), 1993, p 1410-1421.

Acar Y.B. and Alshawabkeh, A. “Electrokinetic Remediation: An Assessment of Principles.” Conference

Proceedings: EPRI Electrokinetics Workshop, Palo Alto, CA, 1994, EPRI TR-104170:49-54.

Murdoch. L., Patterson, B.; Losonsky, G. and Harrar, W. Technologies of delivery or recovery for the

remediation of hazardous waste sites. EPA/600/2-89/066. U.S. Environmental Protection Agency, Risk

Reduction Engineering Laboratory, Cincinnati, Ohio, 1990. NTIS: PB90-156225.