U.S. EPA Contaminated Site Cleanup Information (CLU-IN)

U.S. Environmental Protection Agency
U.S. EPA Technology Innovation and Field Services Division


Treatment Technologies


Arsenic cannot be destroyed in the environment; it can only change its form or become attached to or separated from particles. It may change its form by reacting with oxygen or other molecules present in air, water, or soil, or by the metabolic action of of plants or animals.

Arsenic is a contaminant of concern in ground water at many remediation sites. Because it readily changes valence states and reacts to form species with varying toxicity and mobility, effective treatment of arsenic can be challenging. Treatment of contaminated groundwater can result in residuals that, under some environmental conditions, have unstable toxicity and mobility. In addition, the revised MCL for arsenic in drinking water could result in lower treatment goals for aboveground treatment systems. A lower treatment goal may significantly affect the selection, design, cost, and operation of arsenic treatment systems.

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Overview Reports | Cost Analysis | Specific Treatment Technologies | Site-Specific Information | Literature References

Overview Reports

Arsenic Removal from Drinking Water
Bianchelli, Tatiana (ed.)
Nova Science Publishers. ISBN:1590337239, 150 pp., 2003.

Adobe PDF LogoArsenic Removal in Water Treatment Facilities: Survey of Geochemical Factors and Pilot Plant Experiments
S.D. Wilson, W.R. Kelly, and T.R. Holm, and J.L. Talbott. 79 pp, 2002.
Contact: Steve Wilson

Adobe PDF LogoArsenic Treatment Technologies for Soil, Waste, and Water
EPA 542-R-02-004, 1 Volume + 2 Appendices, 2002
Contact: Linda Fiedler,
Appendix A: Literature Search Results (367K/PDF)
Appendix B: Sites with Arsenic as a Superfund Constituent of Concern (137K/PDF)

This report summarizes information on 13 technologies used to treat arsenic: in situ soil flushing, solidification/stabilization, vitrification, soil washing/acid extraction, pyrometallurgical treatment, electrokinetics, and phytoremediation for soil; precipitation-coprecipitation, membrane filtration, adsorption, ion exchange, permeable reactive barriers, and biological treatment for water.

Adobe PDF LogoArsenic Treatment Technology Evaluation Handbook for Small Systems
U.S. EPA, Office of Groundwater and Drinking Water.
EPA 816-R-03-014, 150 pp, 2003.
Contact: Safe Drinking Water Hotline,

Chemistry and Treatment of Arsenic in Drinking Water
Narasimhan, Ramesh, Bruce Thomson, Joe Chwirka, & Jerry Lowry.
American Water Works Association. ISBN:1583212760, 550 pp., 2005.

Disposal of Waste Resulting from Arsenic Removal Processes
D. Cornwell, M. MacPhee, R. Mutter, J. Novak, and M. Edwards.
IWA Pub., London. AwwaRF Report 90953F, ISBN: 1843398559, 206 pp, 2004 [Originally released to Awwa Research Foundation subscribers in 2003]

The objective of this work was to better understand the factors that cause the release of arsenic from solid residuals and allow arsenic to re-enter the environment. These guidelines help those who are in the process of selecting an arsenic removal treatment technology to also identify the types of residuals that would be generated, the expected arsenic concentrations, and any pre-treatment strategies required prior to final disposal.

Adobe PDF LogoFinal Report on Treatment of Arsenic Residuals from Drinking Water Removal Processes

Adobe PDF LogoFinal Report on Treatment of Arsenic Residuals from Drinking Water Removal Processes
M.J. MacPhee, G.E. Charles, and D.A. Cornwell.
EPA 600-R-01-033, 96 pp, 2001.
Contact: Thomas J. Sorg,

In-Situ Remediation of Arsenic-Contaminated Sites
Bundschuh, J., H.M. Hollaender, and L.Q. Ma (eds).
CRC Press, Boca Raton, FL. ISBN: 9781138747753, 208 pp, 2018 [Table of Contents]

The scientific background of arsenic contamination, remediation case studies, and future perspectives of in situ arsenic remediation technologies for soils and groundwater at geogenic and anthropogenic As-contaminated sites are discussed. Technologies covered include geochemical, microbiological, and plant-based ecological solutions for As remediation.

Adobe PDF LogoProven Alternatives for Aboveground Treatment of Arsenic in Groundwater
EPA-542-S-02-002, 68 pp, 2002
Contact: Linda Fiedler,

This issue paper, developed for EPA's Engineering Forum, identifies and summarizes experiences with proven aboveground treatment alternatives for arsenic in groundwater, and provides information on their relative effectiveness and cost for precipitation/coprecipitation, adsorption, ion exchange, and membrane filtration. The report describes the theory and operation of each technique, available project-specific performance and cost data, and limitations. The report also discusses special considerations for retrofitting systems to meet the lower arsenic drinking water standard (maximum contaminant level or MCL) of 10 µg/l.

Adobe PDF LogoProven Technologies and Remedies Guidance: Remediation of Metals in Soil
Burger, K., P. Carpenter, M. Finch, H. Muniz-Ghazi, D. Oudiz, K. Shaddy, and J. Sotelo.
California Department of Toxic Substances Control, 420 pp, 2008

This guidance streamlines the cleanup process by (1) limiting the number of evaluated technologies to excavation/disposal and containment/capping; (2) facilitating remedy implementation; and (3) facilitating documentation and administrative processes. The focus is on commonly encountered metal contaminants: arsenic, chromium, lead, and mercury. This approach is not intended to replace the evaluation of innovative and new technologies.

Adobe PDF LogoRecent Developments for in Situ Treatment of Metal Contaminated Soils
EPA-542-R-97-004, 64 pp, 1997

Adobe PDF LogoReview of Arsenic Removal Technologies for Contaminated Groundwaters
Vu, K.B., M.D. Kaminski, and L. Nunuz, Argonne National Laboratory.
ANL-CMT-03/2, 43 pp, 2003

Technology Selection and System Design: U.S. EPA Arsenic Removal Technology Demonstration Program, Round 1
Lili Wang, W.E. Condit, and A.S.C. Chen, Battelle, Columbus, OH.
EPA 600-R-05-001, 49 pp., 2004.

This report reviews the source water quality characteristics at each of 12 demonstration sites and presents the rationale behind the selection of an arsenic removal technology for each site. The report also summarizes the design and operation of each of the technologies: nine adsorptive media systems, one anion exchange system, one coagulation/filtration system, and one system modification to a MnO2-coated anthrasand filtration system.

Treatment Technologies for Arsenic Removal
U.S. EPA, National Risk Management Research Laboratory, Cincinnati OH.
EPA 600-S-05-006, 12 pp, 2005
Contact: Darren Lytle,

This booklet provides information about treatment technologies for arsenic removal to the MCL of 10 ug/L, as well as design considerations for choosing treatment technologies.

The Use of Molecular and Genomic Techniques Applied to Microbial Diversity, Community Structure, and Activities at DNAPL and Metal-Contaminated Sites: Environmental Research Brief
Azadpour-Keeley, A., M.J. Barcelona, K. Duncan, and J.M. Suflita.
EPA 600-R-09-103, 19 pp, Sep 2009

Subsurface microbial communities will respond both to the presence of contaminants, which can be detected during characterization, and to the engineered manipulation of subsurface conditions, which can be monitored during remediation. This Brief provides a background on classic molecular and genomic sciences and discusses the results and interpretation of their application to field-scale subsurface remediation activities.

Cost Analysis

Adobe PDF LogoCapital Costs of Arsenic Removal Technologies: U.S. EPA Arsenic Removal Technology Demonstration Program, Round 1
A.S.C. Chen, L. Wang, J.L. Oxenham, and W.E. Condit, Battelle, Columbus, OH.
EPA 600-R-04-201, 54 pp., 2004.

This report provides a brief description of each of the 12 Round 1 demonstration sites and the respective technologies being evaluated, i.e., 9 adsorptive media systems, 1 ion exchange system, 1 coagulation/filtration system, and 1 process modification. Capital costs are organized into categories for equipment, engineering, and installation, and then summed to arrive at a total capital investment cost for each system.

Adobe PDF LogoCosts of Arsenic Removal Technologies for Small Water Systems: U.S. EPA Arsenic Removal Technology Demonstration Program
Wang, L. and A.S.C. Chen.
EPA 600-R-11-090, 92 pp, 2011

Between July 2003 and July 2011, EPA conducted 50 full-scale demonstration projects on treatment systems removing arsenic from drinking water in 26 states. This report summarizes cost data across all demonstrations, grouped by technology type. Treatment systems selected for demonstration included 28 adsorptive media (AM) systems, 18 iron removal and coagulation/filtration systems, two ion exchange systems, and one each reverse osmosis (RO), point-of-use RO, and point-of-use AM.

Federal Remediation Technology Roundtable Technology Cost and Performance Reports

Technologies and Costs for Removal of Arsenic from Drinking Water
U.S. EPA, Office of Water.
EPA-815-R-00-028, 284 pp, 2000.
Contact: Amit Kapadia,

Specific Treatment Technologies

Adobe PDF LogoAddressing the Mobilization of Trace Metals in Anaerobic Aquifers
Pearce, M.S. and M. Waldron.
Proceedings of the 2011 Georgia Water Resources Conference, April 11-13, 2011, University of Georgia. 5 pp, 2011

This paper outlines the manner in which arsenic is mobilized within the subsurface, describes methods that have been proposed or implemented to minimize arsenic mobilization, and offers a chemical solution that reduces or eliminates the mobilization of arsenic in anaerobic aquifers. The chemical solution is designed to prevent the dissolution of pyrite based on Le Chatelier's Principle and the reaction between dissolved oxygen and sulfides. Sulfide injection was tested during startup of a new, potable-water, aquifer storage and recovery (ASR) system for the City of DeLand, FL. Following several successful mini-scale tests and a 5-MG cycle test, a preliminary large-scale test was designed to inject, store, and recover 20 MG. Results indicate that the addition of sulfides to injected water can limit arsenic mobilization to levels that remain far below regulatory requirements. No significant problems were encountered while implementing this treatment approach other than that the recovered water contained low levels of residual sulfides.

Adobe PDF LogoAnaerobic Biostimulation for the In Situ Precipitation and Long-Term Sequestration of Metal Sulfides
M. DeFlaun, J. Lanzon, M. Lodato, S. Henry, T.E. Onstott, E. Chan, and B. Otemuyiwa.
SERDP Project ER-1373, 175 pp, 2009

A small-scale field pilot demonstration began at the Avon Park Air Force Range in Florida at ST-65 in January 2008 in a 30-ft by 30-ft target zone in the area of highest As concentration. Injections of sodium lactate, ferrous sulfate, diammonium phosphate, and ethanol began in April 2008 and were distributed by a groundwater recirculation system to stimulate indigenous sulfate-reducing bacteria. The final amendment injection consisted of sodium lactate, sodium sulfate, and diammonium phosphate. Arsenic concentrations decreased by up to two orders of magnitude to ~0.01 µM (1.4 ppb) between March and September 2008.

Adobe PDF LogoAquatic Arsenic: Phytoremediation Using Floating Macrophytes
Rahman, M.A. and H. Hasegawa.
Chemosphere 83(5):633-646(2011)

This paper reviews the state of current knowledge on arsenic phytoremediation by common aquatic macrophytes (e.g., water hyacinth, watercress).

Adobe PDF LogoArsenic Oxidation Demonstration Project—Final Report. Mine Waste Technology Program Activity III, Project 7
MSE Technology Applications, Inc., Butte, MT
MWTP-84, 147 pp, 1998

Describes a 1996 demonstration of a process developed by the Australian Nuclear Science and Technology Organization (ANSTO) to photo-oxidize, remove, and/or immobilize arsenic in mine effluents.

Arsenic Remediation Through Sustainable Phytoremediation Approaches
Srivastava, S., A. Shukla, V.D. Rajput, K. Kumar, T. Minkina, S. Mandzhieva, A. Shmaraeva, and P. Suprasanna. | Minerals 11(9):936(2021)

Adobe PDF LogoArsenic Removal from Groundwater Using Zero-Valent Iron: Pilot Application in Geothermal Regions
Tyrovola, K., N.P. Nikolaidis, and N. Veranis.
PROTECTION2004. Technical University of Crete , 8 pp, 2004

AsRT technology involves the use of iron filings (zero-valent iron) and sand to reduce inorganic arsenic species to iron co-precipitates, mixed precipitates, and (in conjunction with sulfates) arsenopyrites. The method can be employed, for example, as part of a permeable reactive barrier groundwater treatment system, or ex situ in groundwater pump and treat.

EPA Arsenic Removal Demonstration Program

Adobe PDF LogoBioremediation of Arsenic, Chromium, Lead, and Mercury
Prepared by Adebowale Adeniji, a National Network of Environmental Management studies grantee, under a fellowship from U.S. EPA. 43 pp, 2004.

Adobe PDF LogoBiotransformation of Dimethylarsinic Acid: Engineering Issue
U.S. EPA, Engineering Technical Support Center.
EPA 600-R-14-219, 14 pp, 2014

A Data-Driven Modeling Approach for the Sustainable Remediation of Persistent Arsenic (As) Groundwater Contamination in a Fractured Rock Aquifer through a Groundwater Recirculation Well (IEG-GCW®)
Ciampi, P., C. Esposito, E. Bartsch, E.J. Alesi, G. Rehner, P. Morettin, M. Pellegrini, S. Olivieri, M. Ranaldo, G. Liali, and M.P. Papini. | Environmental Research 217:114827(2023)

An innovative remediation technology was implemented to remove As from a heavily contaminated, fractured aquifer at an industrial site. Groundwater circulation well (GCW) technology was tested to significantly increase and accelerate the mobilization and removal of As in the source area. A 45-m deep IEG-GCW® system, equipped with four screen sections at different depths, and a treatment system for the removal of As by oxidation and filtration on Macrolite, were installed. A geomodeling approach supports both remediation and multi-source data interpretation. The first months of operation demonstrate the hydraulic effectiveness of the IEG-GCW® system in the fractured rock aquifer and the ability to significantly enhance As removal compared to conventional pumping wells currently feeding a centralized treatment system. The recirculation flow rate amounts to ~ 2 m3/h. Water pumped and treated by the GCW system is reintroduced with As concentrations reduced (average of 20%-60%). During the pilot test, the recirculating system removed 23 kg As, while the central pump-and-treat (P&T) system removed 129 kg, although it treated 100 x more water volume. The P&T system removed 259 mg As per m3 of treated groundwater, while the GCW removed 4,814 mg As per m3 of treated groundwater.

Design Manual: Removal of Arsenic from Drinking Water Supplies by Iron Removal Process
G.L. Hoffman, D.A. Lytle, T.J. Sorg, A.S.C. Chen, and L. Wang.
EPA 600-R-06-030, 78 pp, 2006.
Contact: Thomas Sorg,

Electrochemical Treatment to Facilitate and Improve Arsenic Removal
G. Korshin, J. Kim, and A. Velichenko.
IWA Pub., London. AwwaRF Report 91030F, ISBN: 1843399180, 126 pp, July 2006

Adobe PDF LogoEnvironmental Technology Verification Report: Removal of Arsenic in Drinking Water, Basin Water High Efficiency Ion Exchange Treatment System
U.S. EPA, Cincinnati, OH.
EPA 600-R-05-117, 159 pp, 2005.

Environmental Technology Verification Report: Removal of Arsenic in Drinking Water, Pall Corporation Microza(R) Microfiltration System
U.S. EPA, Cincinnati, OH.
EPA 600-R-05-120, 97 pp, 2005.

Field Application of a Permeable Reactive Barrier for Treatment of Arsenic in Ground Water
R.T. Wilkin, S.D. Acree, D.G. Beak, R.R. Ross, T.R. Lee, and C.J. Paul.
EPA 600-R-08-093, 81 pp, 2008

In June 2005, a pilot-scale PRB containing granular iron was installed at a former metal smelting facility near Helena, MT, to treat ground water contaminated with concentrations (>25 mg/L) of arsenite and arsenate. The barrier is 9.1 m long, 14 m deep, and 1.8 to 2.4 m wide (in the direction of ground-water flow). Within the PRB, As concentrations are 2 to <0.01 mg/L. After 2 years of operation, significant decreases in As concentrations are evident. This report covers site characterization, remedial design and implementation, and monitoring results for this pilot-scale PRB. Additional information: (Wilkin et al. 2009, Abstract)

Adobe PDF LogoField Demonstration of Zerovalent Iron Treatment Technology in Parker Brothers Arroyo: Status Report
Texas Custodial Trust, El Paso, 94 pp, 2014

Environmental impacts from historical smelting operations are present within and outside the site of the former ASARCO smelter (El Paso, Texas). In Parker Brothers Arroyo, the site contractor completed construction of two in situ ZVI-based PRBs in October 2012 and the performance monitoring network in June 2013. This status report presents construction details for the PRBs with subsequent performance results. The objectives of the field demonstration are to verify the effectiveness of the ZVI PRB technology for concentrations of As, Sb, Se, and thallium above regulatory requirements at this site, initiate groundwater remediation, and provide data to support the final site-wide groundwater remedy. Additional information: Other Technical Reports.

Adobe PDF LogoField Study on Application of Soil Washing System to Arsenic-Contaminated Site Adjacent to J. Refinery in Korea
Kim, K., J.-G. Cheong, W.-H. Kang, H. Chae, and C.-H. Chang.
International Conference on Environmental Science and Technology: IPCBEE 30:1-5(2012)

The site is contaminated with metals, particularly arsenic, scattered in dust from the refinery's stack. A soil washing plant with a capacity of 3 ton/hr was installed on the site and has been in operation since October 2010. The authors evaluated the results obtained when washing soils of different particle size (sandy or silty) and developed recommendations for an optimized remediation scenario based upon soil texture.

Adobe PDF LogoFirst Five-Year Review Report for Valley Wood Preserving, Inc., Superfund Site, Turlock, CA
U.S. EPA Region 9, 91 pp, Sep 2009

The selected groundwater remedy for a migrating Cr(VI) plume in the 1991 ROD was electrochemical treatment in conjunction with existing pump and treat. During a 33-month (1998-2000) pilot study, extracted groundwater was treated via the existing electrochemical precipitation system, with addition of calcium polysulfide to the treated water prior to reinjection. The calcium polysulfide reacted with the Cr(VI) in situ, reducing it to Cr(III). The pilot essentially eliminated the Cr(VI) plume from most of the wells on site and all of the wells off site. Pursuant to ROD Amendment 2, in situ treatment for an arsenic groundwater plume was completed in October 2007 using injections of ViroBind(tm) F Blend reagent slurry to immobilize and incorporate arsenic permanently into ferrous iron minerals and to continue reduction of residual Cr(VI) to Cr(III). Arsenic concentrations fell by as much as 2 orders of magnitude after the treatment.

Adobe PDF LogoHigh-Level Arsenite Removal from Groundwater by Zero-Valent Iron
H.L. Lien and R.T. Wilkin. Chemosphere, 59(3):377-386 Apr 2005.

Innovative Alternatives to Minimize Arsenic, Perchlorate, and Nitrate Residuals
J. Min, L. Boulos, J. Brown, D. Cornwell, Y. Le Gouellec, E. Coppola, J. Baxley, J. Rine, J. Hering, and N. Vural.
IWA Pub., London. AwwaRF Report 91054F, ISBN: 1843399342, 200 pp, 2006

This report presents treatment and residuals minimization technologies for arsenic (backwash minimization, backwash stabilization, and brine solidification), perchlorate and nitrate (biological brine treatment, thermal brine treatment, and biological treatment of perchlorate- and nitrate-laden wastewater).

Iron-Based Subsurface Arsenic Removal (SAR): Results Of A Long-Term Pilot-Scale Test In Vietnam
Kurz, E.E.C., V.T. Luong, U. Hellriegel, F. Leidinger, T.L. Luu, J. Bundschuh, and J. Hoinkis.
Water Research 181:115929(2020)

A pilot-scale SAR plant was tested in the Mekong Delta, Vietnam for Fe, As, and Mn removal over two years. Initial concentrations of Fe (8.4 ± 1.3 mg/L) and As (81 ± 8 µg/L) in the exploited groundwater were successfully lowered to below World Health Organization guideline value limits for drinking water. Adsorption and co-precipitation of As with Fe-(hydr)oxides were the principal mechanism responsible for As removal. Naturally occurring geochemical reducing conditions and high ammonium levels in the groundwater delayed the removal of Mn. An additional post-treatment filtration to remove Mn was temporarily used to comply with the Vietnamese drinking water standard until the SAR process achieved Mn mitigation. Longer abstract

Adobe PDF LogoLong-Term Arsenic Sequestration in Biogenic Pyrite from Contaminated Groundwater: Insights from Field and Laboratory Studies
Fischer, A., J. Saunders, S. Speetjens, J. Marks, J. Redwine, S.R. Rogers, A.S. Ojeda, Md M. Rahman, Z.M. Billor, and M.-K. Lee. | Minerals 11:537(2021)

A study was conducted to demonstrate the effectiveness of sulfate-reducing bacteria (SRB) to remediate arsenic using a ferrous sulfate and molasses mixture at an industrial site in Florida over nine months. The optimal dosage of the remediating mixture consisted of 5 kg of ferrous sulfate, ~27 kg of molasses, and ~1 kg of fertilizer per 3785.4 L of water. The mixture was injected into 11 wells hydrologically upgradient of the arsenic plume to attempt full-scale remediation. Analyses determined that As was sequestered, primarily in the form of arsenian pyrite, which rapidly precipitated as euhedral crystals and spherical aggregates 1-30 µm in diameter within two weeks of the injection. Analyses confirmed that the mixture and injection scheme reduced As concentrations to near or below the site's clean-up standard of 0.05 mg/L in nine months. In addition, the arsenian pyrite contained 0.03-0.89 weight percentage (wt%) of sequestered arsenic, with >80% of groundwater arsenic removed by SRB biomineralization.

Mine Waste Technology Program Activity III, Project 42: Physical Solutions for Acid Rock Drainage at Remote Sites Demonstration Project
McCloskey, J. and R. Hiebert.
EPA 600-R-09-160, 53 pp, 2008

MSE Technology Applications, Inc.'s Reductive Precipitation Process, a 2-stage iron precipitation/filtration process with a polishing step to remove arsenic, is designed to treat high-iron acid rock drainage. When the process was implemented at the Susie Mine (Montana), with an emphasis on zinc and arsenic removal, zinc was removed effectively and the level of arsenic fell substantially, but the field system was unable to achieve arsenic levels below 10 µg/L. Owing to numerous process upsets, a shortened schedule with minimal process optimization, and elimination of the polishing step, the lowest arsenic level measured in the treated effluent was 51.9 µg/L, although the process generally was effective for the removal of Cd, Cu, Pb, Fe, and Mn.

Monitored Natural Attenuation of Inorganic Contaminants in Ground Water, Volume 2: Assessment for Non-Radionuclides, Including Arsenic, Cadmium, Chromium, Copper, Lead, Nickel, Nitrate, Perchlorate, and Selenium
EPA 600-R-07-140, 2007

In a separate chapter for each listed contaminant, Volume 2 of 3 describes (1) the natural immobilization or degradation processes that can result in the attenuation of the contaminant and (2) data requirements to be met during site characterization. The document emphasizes characterization of immobilization and/or degradation processes that may control contaminant attenuation, as well as technical approaches to assess performance characteristics of the MNA remedy. A tiered analysis approach is presented to assist in organizing site characterization tasks.

Adobe PDF LogoPerformance Evaluation of ALCANAASF50-Ferric Coated Activated Alumina and Granular Ferric Hydroxide (GFH) for Arsenic Removal in the Presence of Competitive Ions in an Active Well: Kirtland Field Trial, Initial Studies
N.R. Khandaker, J. Krumhansl, L. Neidel, and M. Siegel. SAND2005-7693, 40 pp, 2006.

Phytoremediation at Ryeland Road Arsenic Site, Heidelberg Township, PA
U.S. EPA Superfund Site Web Page.

The 7.3-acre Ryeland Road Arsenic site is located in Berks County, Pennsylvania. Past operations contaminated soil and groundwater on part of the property with arsenic, lead, and other chemicals. In addition to excavation and removal of contaminated materials, a pilot study initiated in May 2007 determined that phytoextraction by ferns was a successful method to reduce arsenic in shallow soils and areas saturated by springs. Full-scale efforts have been ongoing since 2009. The ferns have demonstrated their effectiveness in over 30% of the area where arsenic contamination once existed along the stream. Additional information: FWS fact sheetAdobe PDF Logo

Adobe PDF LogoPhytoremediation Field Studies Database for Chlorinated Solvents, Pesticides, Explosives, and Metals
Prepared by Ana Hoffnagle and Cynthia Green under internships with U.S. EPA. 168 pp, 2004.

The paper briefly explains the concept of phytoremediation, details phytoremediation site considerations, and summarizes the successes and failures of field-scale sites where phytotechnologies have been applied or proposed.

Remediation of Persistent Arsenic Groundwater Contamination in a Fractured Rock Aquifer in a Coastal Area by Using IEG-GCQW® Groundwater Circulation
Papini, M.P., G. Rehner, P. Ciampi, E.J. Alesi, E. Bartsch, M. Pellegrini, S. Olivieri, F. Bonfanti, and G. Liali. | AquaConSoil 2021, 15-17 June, virtual, abstract only, 2021

Groundwater contaminated with arsenic (As) from a major incident at a fertilizer manufacturing site represented a significant environmental problem ~45 years after the event. After a major explosion, a portion of As was transported vertically into the fractured rock formation of the aquifer, where the deposits continue to act as an active secondary source contaminating the groundwater. Traditional pump and treat technology managed and reduced the impact of contamination outside site boundaries. However, a significant mass of As was trapped in the fractured aquifer contaminating groundwater up to 40 m bgs. Groundwater Circulation Well (GCW) technology was chosen to enhance As mobilization in the source area. A pilot plant consisting of a 40 m deep IEG-GCW®, equipped with 4 screens at different depths and a treatment system to remove dissolved As by oxidation and filtration on Macrolite, was started in 2020. The hydraulic effectiveness of the IEG-GCW® in a fractured rock aquifer (pumping rate ~2.5 m3 /h and ROI ~15 m) and the capability to increase pollutant mobilization significantly compared to the traditional pumping wells were demonstrated within the first few months of operation. Results showed that upconing of the coastal saltwater present at 45 m bgl could be controlled and reverted using a properly designed GCW. The pilot test is ongoing and will generate general design parameters for the remediation plan for industrial sites in coastal areas with fractured rock aquifers.

Adobe PDF LogoRemoval Processes for Arsenic in Constructed Wetlands
Lizama, A.K., T.D. Fletcher, and G. Sun, Monash Univ., VIC, Australia.
Chemosphere 84(8):1032-1043(2011)

This paper reviews current understanding of arsenic removal processes in wetland environments, discusses implications for treatment wetlands, and identifies critical knowledge gaps and areas for future research.

Site Characterization to Support Use of Monitored Natural Attenuation for Remediation of Inorganic Contaminants in Ground Water
R.G. Ford, R.T. Wilkin, and S. Acree.
EPA 600-R-08-114, 16 pp, 2008

This Issue Paper highlights at what stage of the process solid-phase characterization techniques need to be implemented during site characterization and describes two case studies (one site affected by arsenic, lead, and chromium, and the other by uranium) where the results of these techniques were critical to evaluation of MNA as a potential component of ground-water cleanup.

Strategic Selection of an Optimal Sorbent Mixture for In-Situ Remediation of Heavy Metal Contaminated Sediments: Framework and Case Study
Chiang, Y.W., R.M. Santos, K. Ghyselbrecht, V. Cappuyns, J.A. Martens, R. Swennen, T. Van Gerven, and B. Meesschaert.
Journal of Environmental Management 105:1-11(2012)

This paper outlines a strategic framework designed to address the development of an in situ sediment remediation solution systematically through assessment, feasibility, and performance studies. The decision-making tools and the experimental procedures needed to identify optimum sorbent mixtures are detailed, with emphasis on the utilization and combination of commercially available and waste-derived sorbents. An application of the proposed framework is illustrated in a case study of a contaminated sediment site in Northern Belgium with high levels of As, Cd, Pb, and Zn originating from historical non-ferrous smelting. Longer abstract

Technology Performance Review: Selecting and Using Solidification/Stabilization Treatment for Site Remediation
U.S. EPA, National Risk Management Research Laboratory, Cincinnati, OH.
EPA 600-R-09-148, 28 pp, 2009

Solidification/stabilization (S/S) is used to prevent migration of contaminants from contaminated soil, sludge, and sediment. Solidification refers to a process that binds a contaminated medium with a reagent, such as Portland cement, changing its physical properties. Stabilization involves a chemical reaction that reduces the leachability of a waste. The effectiveness of S/S has been demonstrated for non-volatile metals (e.g., arsenic, chromium), radioactive materials, halogenated semivolatiles, non-halogenated nonvolatiles and semivolatiles, PCBs, and pesticides, and potentially dioxins/furans. For treating organic contaminants (e.g., creosote), the use of certain materials such as organophilic clay and activated carbon, either as a pretreatment or as additives in cement, can improve contaminant immobilization. This review addresses important factors to consider in the selection of S/S treatment and discusses its implementation at seven sites.

Treatment of Aqueous Arsenic - A Review of Biosorbent Preparation Methods
Benis, K.Z., A.M. Damuchali, K.N. McPhedran, and J. Soltan.
Journal of Environmental Management 273:111126(2020)

This review includes an overview of 53 recent studies that assess a variety of biomass modification methods, such as activation with acids or bases and biomass-based composites, meant to overcome issues commonly experienced when using untreated biomass. Future perspectives are provided to assist in the further optimization of methods for biomass modifications to enhance As sorption capacities. Longer abstract.

Site-Specific Information

U.S. EPA Environmental Technology Verification (ETV) Program Verifications
Contact: Teresa Harten,

Arsenic Drinking Water Treatment Technology Demonstrations

Identifies research topics under U.S. EPA's Small Business Innovation Research (SBIR) / Science to Achieve Results (STAR) programs.

Literature References

Technology Innovation News Survey Archives
The Technology Innovation News Survey archive contains resources gathered from published material and gray literature relevant to the research, development, testing, and application of innovative technologies for the remediation of hazardous waste sites. The collected abstracts date from 1998 to the present, and the archive is updated twice each month.