Polychlorinated biphenyls (pcbs)

Treatment Technologies

Because 40 CFR 761 specifies incineration for materials containing over 500 ppm PCBs, incineration is one of the most used remediation technologies; however, from a handling perspective, it is often better to use onsite ex situ thermal desorption of contaminated soils/sediments with the PCBs in the offgases being captured for offsite treatment. In situ thermal desorption/destruction of PCBs has been demonstrated but the method has not been commonly employed.

Excavation and disposal in an offsite TSCA permitted landfill is another commonly used option as was demonstrated for dredged PCB contaminated sediments at the Ashtabula River cleanup.

The Interstate Technology & Regulatory Council (ITRC) in their Technical and Regulatory Guidance for In Situ Chemical Oxidation of Contaminated Soil and Groundwater, Second Edition (2005) did not find in situ chemical oxidants to be very effective in treating PCBs. This may be because these chemicals are most effective when the target chemicals are dissolved.

While anaerobic biodegradation of PCBs has been demonstrated, it is usually congener specific, and for the more chlorinated biphenyls, it is slow. Evidence to date does not support degradation of all congeners nor does it show that one microbe may be capable of degrading most of them (e.g., Pieper 2008 and Bedard 2007).

A full scale PCB cleanup using in situ vitrification was performed at the General Electric, Inc., Spokane Shop in the 1990s; however, in situ vitrification is not a commonly used technology.

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General Information

Destruction Technologies for Polychlorinated Biphenyls (PCBS)
M.S.M. Mujeebur Rahuman (ICS-UNIDO); Luigi Pistone (SiiRTEC NIGI S.p.A., Milan, Italy);
Ferruccio Trifir (Univ. of Bologna, Italy); Stanislav Miertus (ICS-UNIDO).
International Centre for Science and High Technology, United Nations Industrial Development Organization (ICS-UNIDO), Trieste, Italy. 55 pp, 2000.

The emerging and innovative technologies being tested or implemented for PCB cleanup form a lengthy list: supercritical oxidation, electrochemical oxidation, solvated electron technology, chemical reduction reaction, dehalogenation processes (base catalyzed decomposition and apeg plus), molten metal pyrolysis, molten salt oxidation, plasma arc, catalytic hydrogenation, ultrasonic technology, the advanced oxidative process, solvent extraction/chemical dehalogenation/radiolytic degradation, solar detoxification/photochemical degradation, thermal desorption integrated technologies (thermal desorption/catalysed dehalogenation, thermal desorption/pyrolysis, thermal desorption/retort system, and vitrification), and biological technologies (bioslurry and enhanced bioremediation).

Emerging Technologies for the In Situ Remediation of PCB-Contaminated Soils and Sediments: Bioremediation and Nanoscale Zero-Valent Iron
2004

This document was prepared by Alex Mikszewski, a National Network of Environmental Management studies grantee, under a fellowship from the U.S. Environmental Protection Agency. This report reviews emerging technologies for the in situ remediation of PCB-contaminated sediments and soils to assess their viability for future employment. This report was not subject to EPA peer review or technical review. EPA makes no warranties, expressed or implied, including without limitation, warranty for completeness, accuracy, or usefulness of the information.

Engineering Issue: Technology Alternatives for the Remediation of PCB-Contaminated Soil and Sediment
Davila, B., K.W. Whitford, and E.S. Saylor.
EPA 540-S-93-506, 26 pp, 1993.

Engineering Issue: Technology Alternatives for the Remediation of PCB Contaminated Soils and Sediments
Cook, K.
EPA 600-S-13-079, 40 pp, June 2012

This engineering issue paper provides an overview of PCB contamination and remediation in soil and dredged sediment. This information includes the type of data and site characteristics needed by site cleanup managers to evaluate primarily ex situ technologies—incineration, landfill disposal, thermal desorption, solvent extraction, solidification/stabilization, and chemical dehalogenation—for potential applicability to hazardous waste site cleanup.

Planning for Polychlorinated Biphenyl (PCB)-Containing Disaster Debris
U.S. EPA, 33 pp, 2011

This document supplements EPA's 2008 Planning for Natural Disaster Debris guidance to provide more detailed information on the management of PCB-containing debris in emergency situations that arise from natural disasters. The focus is on electrical equipment and materials containing or contaminated by PCBs. While specifically addressing PCB spills/releases caused by natural disasters (e.g., tornados, hurricanes, floods), this information also can be useful for other types of emergency situations, such as explosions.

Recent Advances in PCB Removal from Historically Contaminated Environmental Matrices
Sredlova, K. and T. Cajthaml. | Chemosphere 287(Part 1):132096(2022)

A literature search on recent advances in different techniques and approaches to remediate historically PCB-contaminated matrices is discussed in this review. Current knowledge shows that PCBs are not sufficiently removed from the environment by natural processes, and the suitability of some approaches (e.g., natural attenuation) is limited. Physicochemical processes remain effective, but extensive use is constrained by their high costs and frequent destructiveness toward the matrices. Despite limited reliability, the application of biological methods combined with other techniques could be promising. Other aspects discussed in this work include: 1.) The incompleteness of some studies; 2.) Attention should be given to evaluating toxicity during processes, particularly in terms of monitoring different modes of toxic action; and 3.) Decomposition mechanisms and products need to be sufficiently clarified before combined, tailor-made approaches can be employed. Longer abstract

Reference Guide to Non-combustion Technologies for Remediation of Persistent Organic Pollutants in Soil, Second Edition - 2010

This report is the second edition of the U.S. Environmental Protection Agency's (US EPA's) 2005 report and provides a high level summary of information on the applicability of existing and emerging noncombustion technologies for the remediation of persistent organic pollutants (POPs) in soil. Since the publication of this report in 2005, nine (9) additional chemicals have been listed in the Stockholm Convention; this brings the total number of chemicals currently listed as POPs under the Stockholm Convention to twenty-one (21). In addition, three (3) POPs are currently under consideration.

Review of Emerging, Innovative Technologies for the Destruction and Decontamination of POPs and the Identification of Promising Technologies for Use in Developing Countries
Univ. of Auckland, New Zealand. United Nations Environment Programme, Global Environmental Facility, Scientific and Technical Advisory Panel. GF/8000-02-02-2205, 138 pp., 2004.

This report reviews existing non-combustion technologies and identifies those that are emerging, innovative, and promising for the destruction of persistent organic pollutants (POPs) stockpiles. POPs include many of the first generation organochlorine insecticides (DDT, aldrin), industrial chemical products (PCBs), and unwanted byproducts such as dioxins and furans. The report identifies 5 emerging and promising technologies and encourages their rapid commercialization: ball milling, the GeoMelt^TM process, mediated electrochemical oxidation via CerOx, mediated electrochemical oxidation via the AEA Silver II Process, and catalytic hydrogenation.

Survey of Currently Available Non-Incineration PCB Destruction Technologies
United Nations Environment Programme (UNEP). UNEP Chemicals, Geneva, Switzerland. 70 pp, 2000.

The methods primarily used on contaminated oils are solvent extraction, cement kilns, and vitrification.

Bioremediation

Bacterial Metabolism of Polychlorinated Biphenyls
Pieper, Dietmar H. and Michael Seeger
J Mol Microbiol Biotechnol 2008;15:121-138

Biodegradation of PCDDs/PCDFs and PCBs
Urbaniak, M.
Biodegradation: Engineering and Technology, R. Chamy and F. Rosenkranz (eds). Intech Open Science, ISBN: 978-953-51-1153-5, Chapter 4:73-100(2013)

This review examines the physical and chemical properties of dioxins and PCBs and how they can be broken down in the environment. Microbiological transformation is discussed with reference to aerobic, anaerobic, and sequential anaerobic-aerobic conditions. Physical transformations include photochemical and thermal degradation. Different phytoremediation processes also can effect environmental degradation of dioxins and PCBs.

The Dehalococcoides Population in Sediment-Free Mixed Cultures Metabolically Dechlorinates the Commercial Polychlorinated Biphenyl Mixture Aroclor 1260
Bedard, D.L., K.M. Ritalahti, and F.E. Löffler
Applied and Environmental Microbiology, April 2007, p. 2513-2521, Vol. 73, No. 8

Enhancing PCB Bioremediation
Talley, J.W., et al. (eds) Federal Integrated Biotreatment Research Consortium (FIBRC): Flask to Field Initiative, ERDC/EL TR-02-37,Appendix D, 507 p, October 2002

Evaluating the Efficacy of Bioaugmentation for In-Situ Treatment of PCB Impacted Sediments
Sowers, K.R., U. Ghosh, and H.D. May.
ESTCP Project ER-201215, 154 pp, 2018

Both anaerobic halorespiring and aerobic PCB-degrading bioamendments were mass cultured, transported to a site, and delivered through a water column to sediments without loss of viability. Treatment with the bioamendment mixture reduced the mean total PCB concentration by an average of 52% and the aqueous PCB fraction by 95% after 13.5 months. The innovative aspect of the technology is the application of activated carbon pellets as a solid substrate for 1) delivery of microorganisms into sediments and 2) sequestration and concentration of hydrophobic PCBs in close proximity to the PCB-transforming bacteria.

Lab-Scale Biodegradation Assay Using Passive Samplers to Determine Microorganisms' Ability to Reduce Polychlorinated Biphenyl (PCB) Volatilization from Contaminated Sediment
Bako, C.M., A. Martinez, R.F.Marek, K.C. Hornbuckle, J.L. Schnoor, and T.E. Mattes. MethodsX 10:102039(2023)

A lab-scale PCB biodegradation assay is described to screen potential bioaugmentation strains or consortia for their ability to decrease PCB mass flux from contaminated sediment to air through biodegradation of freely dissolved PCBs that have desorbed from sediment particles. The assay uses two types of passive samplers to simultaneously measure PCB mass that is freely dissolved in an aqueous solution and PCB mass that has volatilized to the headspace of the bioreactor. Using this approach, relative comparisons of PCB mass accumulated in passive samplers between bioaugmented treatments and controls allow for assessment of a microbial strain's ability to reduce both freely dissolved and vapor phase PCB concentrations. The method is designed to be conducted using aliquots of homogenized, well-characterized, PCB-contaminated sediment gathered from a field site. This work details the experimental design methodology, required materials, bioreactor setup, passive sampling, PCB extraction, sample cleanup, and quantification protocols such that the biodegradation assay can be conducted or replicated. A step-by-step protocol is also included and annotated by experienced analysts.

Pilot-Scale Land Treatment Study at the Saginaw, MI, Confined Disposal Facility
Myers, T.E. and P. Horner, U.S. Army Engineer Research and Development Center, Vicksburg, MS.
ERDC TN-DOER-C35, 10 pp., 2004.
Contact: Tommy Myers, tommy.e.myers@erdc.usace.army.mil, or Pam Horner, Pam.Horner@lre02.usace.army.mil

A pilot-scale study evaluated the technical feasibility of using land treatment technology to remediate dredged material contaminated with hydrophobic organic chemicals. Results from this study and a bench-scale study of the same dredged material both indicated that PCBs in Saginaw River sediment can be reduced via land treatment, though the study showed differences in the extent of reaction (percent PCB removed), with less contaminant reduction shown in the bench-scale data than in the pilot-scale data.

Quantifying Enhanced Microbial Dehalogenation Impacting the Fate and Transport of Organohalide Mixtures in Contaminated Sediments
Haggblom, M., D. Fennell, L. Rodenburg, L. Kerkhof, and K. Sowers.
SERDP Project ER-1492, 221 pp, 2012

The project investigated techniques and amendments to enhance microbial dehalogenation in sediments contaminated with organohalide mixtures and developed methods and tools to monitor the effectiveness of biostimulation processes. Organohalide-contaminated sediments were found to contain diverse communities of dehalogenating microorganisms. Results show that dechlorination of historical PCB and PCDD/F contaminant mixtures can be stimulated by addition of amendments and/or bioaugmentation with dechlorinating bacteria.

Treatability Study Report of Green Mountain Laboratories, Inc.'s Bioremediation Process Treatment of PCB Contaminated Soils at Beede Waste Oil/Cash Energy Superfund Site, Plaistow, New Hampshire
Science Applications International Corporation, Hackensack, NJ.
EPA 540-R-05-006, 44 pp, 2005.

The Use of Enhanced Bioremediation at the Savannah River Site to Remediate Pesticides and PCBs
Beul, R.R. C. Lewis, and S. Baladi.
WSRC-MS-2003-00659, 25 pp, 2003.

Containment

Predicting and Validating the Field Performance of Novel Sorbent-Amended Sediment Caps
Lowry, G.V., J.L. Fairey, D.A. Dzombak, and J.M. VanBriesen.
Cooperative Institute for Coastal and Estuarine Environmental Technology, 36 pp, 2009

This paper contains an evaluation of the performance of thin-layer (1.25 cm) activated carbon (AC)-amended sand sediment caps as a tool for in situ remediation of PCB-contaminated sediments. The investigators developed the fundamental understanding of the physicochemical processes affecting the transport of PCBs through the AC layer and measured isotherms parameters for nine PCBs onto AC under sediment conditions. Addition of a thin layer of AC to a sand cap significantly improves the ability of the cap to retard transport of PCBs from the underlying sediment to the overlying benthic community and water column. The AC layer is added to the sediment cap using a reactive core mat, consisting of a geotextile filled with AC. These mats are commercially available from companies identified in the report.

Season Two In Situ Treatment Completion Report Lockheed Martin Middle River Complex 2323 Eastern Boulevard Middle River, Maryland
Lockheed Martin Corporation, 54 pages, 2018

This completion report summarizes placement of 2,504 tons AquaGate+PAC^® 10% dry weight over 13.7 acres of PCB-contaminated sediment from October to December 2017. The report describes construction performed to place the material and summarizes site preparation, the pre-project pilot study, and quality control procedures. Quality control tests and laboratory analytical sampling results for the surficial sediment confirm that the design intent and project objectives were achieved. The activated carbon concentrations currently in Dark Head Cove sediment are considered adequate to reduce PCB concentrations within the pore water, resulting in an overall reduction of bioaccumulation.

Dredging

Field Study on Environmental Dredging Residuals: Ashtabula River, Volume I. Final Report
Foote, E., G. Durell, S. Williams, J. Hardin, M. Mills, R. Brenner, C. Jones, and J. Magalen.
EPA 600-R-10-126, 82 pp, 2010

Extensive monitoring studies and physical and chemical measurements were carried out prior to, during, and after dredging along a 1,100-ft study area of the Ashtabula River. In addition to estimating the volume and concentration of contaminated sediment residuals remaining after completion of dredging, field efforts focused on comparing pre- and post-dredging sediment mass and concentration characterization data to assess the PCB concentration relationship of the residual sediment to the contaminated material removed. The residuals data indicated consistent sediment and PCB mass removals greater than or equal to 95%. The data also revealed that the sediment residuals layer was composed of more highly contaminated sediments originating from higher elevations in the vertical sediment profile, rather than the lower-concentration sediments removed from immediately above the final post-dredge sediment surface.

A Mass-Balance Approach for Assessing PCB Movement During Remediation of a PCB-Contaminated Deposit on the Fox River, Wisconsin
USGS
Water-Resources Investigations Report 00-4245, 8pp, 2000

In Situ Chemical Oxidation

Engineering Issue Paper: In Situ Chemical Oxidation
EPA 600-R-06-072, 2006

This issue paper was produced by the EPA Risk Management Research Laboratory and the Engineering Forum. It provides an up-to-date overview of ISCO remediation technology and fundamentals, and is developed based on peer-reviewed literature, EPA reports, web sources, current research, conference proceedings, and other pertinent information.

Evaluation of Lime and Persulfate Treatment for Mixed Contaminant Soil from Plum Brook Ordnance Works (Sandusky, OH)
Medina, V.F., S.A. Waisner, A.B. Morrow, C.C. Nestler, and M. Jones.
ERDC/EL TR-07-19, 116 pp, 2007

Soil contaminated with TNT, DNT, a PCB (Araclor 1260), PAHs, and lead was addressed with a series of chemical-based treatments, i.e., application of lime to treat the explosives, advanced oxidation (persulfate and Fenton's reagent) for treatment of PCBs and PAHs, and use of phosphate for stabilizing lead. Lime treatment degraded 98% of TNT, 75% of DNT, and 80% of PCBs, with minimal removal (41%) of PAHs. Similar removal levels were found for persulfate treatment and lime followed by persulfate. Treatments of the most contaminated soil did not meet preliminary remediation goals for explosives or PCBs.

In Situ Reduction

Application of a Bimetallic Treatment System (BTS) for PCB Removal from Older Structures on DoD Facilities
Krug, T., S. O'Hara, J. Quinn, C. Clausen, C. Geiger, and J. Captain.
ESTCP Project RC-200610, 236 pp, 2011

The BTS technology--zero-valent magnesium coated with a small amount of palladium in a solvent solution capable of hydrogen donation--is designed to extract PCBs from weathered, decades-old coating material (i.e., paint) and then degrade the extracted PCBs. Field testing was conducted at Cape Canaveral, FL, and Badger Army Ammunition Plant, WI. The demonstration goal--to reach PCB concentrations below the TSCA limit of 50 ppm in the paint on all structures tested--was achieved, but depending on initial concentrations, multiple BTS applications were required. See also the ESTCP Cost and Performance Report and the Badger project report.

Reductive Dechlorination for Remediation of Polychlorinated Biphenyls
Wu, B.Z., H.Y. Chen, S.J. Wang, C.M. Wai, W. Liao, and K. Chiu.
Chemosphere 88(7):757-768(2012)

This review references 108 papers on reductive treatment for PCBs published within the last decade. The treatments reviewed fall into one of three categories: (1) catalytic hydrodechlorination with H₂, (2) Fe-based reductive dechlorination, and (3) other reductive dechlorination methods (e.g., hydrogen-transfer dechlorination, base-catalyzed dechlorination, and sodium dispersion). The advantages of each remediation technology are discussed. Longer abstract

Monitored Natural Recovery

Methods and Tools for the Evaluation of Monitored Natural Recovery of Contaminated Sediments: Lake Hartwell Case Study
U.S. EPA, National Risk Management Research Laboratory, Cincinnati, OH.
EPA 600-S-10-006, 24 pp, 2010

As part of EPA research to develop methods and tools for the evaluation of MNR of sediments contaminated with PCBs, PAHs, and mercury, a multiyear, interdisciplinary research project was conducted at the Sangamo-Weston, Inc./Twelve-Mile Creek/Lake Hartwell PCB Contamination Superfund Site in Pickens County, SC. The methods and tools described in this summary comprise quantitative approaches for characterizing naturally occurring mechanistic processes relevant to MNR. This information is expected to provide a reference case study for managers considering MNR as a site remedy or monitoring the progress of MNR in contaminated sediments.

Variation in Natural Attenuation Rates of Polychlorinated Biphenyls (PCBS) in Fish from Streams and Reservoirs in East Tennessee Observed Over a 35-Year Period
Matson, P.G., L.M. Stevenson, R.A. Efroymson, R.T. Jett, M.W. Jones, M.J. Peterson, and T.J. Mathews. | Journal of Hazardous Materials 438:129427(2022)

This study presents long-term trends in PCB bioaccumulation in fish found in lower-order tributaries on the Oak Ridge Reservation, an impacted U.S. DoE property in East Tennessee, and an adjacent large reservoir system composed of portions of the Clinch and Tennessee rivers. The reservoir system has experienced no direct PCB mitigation activities and the study served as an opportunity to explore potential natural attenuation of PCBs within a large lotic ecosystem. Attenuation rates ranged from 0% to 8%/yr in minnows and sunfish at stream sites and 5.4-11.3%/yr in catfish at reservoir sites. These rates are comparable to findings from similar studies in other regions, suggesting consistency in responses since PCB production was banned in 1979. Results suggest that PCB sources from discharge outfalls are important locally but are not primarily responsible for sustaining PCB contamination in downstream reservoirs. Longer abstract

Permeable Reactive Barriers

Demonstration of the Aquablok® Sediment Capping Technology: Innovative Technology Evaluation Report
U.S. EPA, National Risk Management Research Laboratory. EPA 540-R-07-008, 145 pp, 2007

AquaBlok® is an innovative, proprietary clay polymer composite that generally comprises a mixture of bentonite clay with polymer additives covering a small aggregate core. Other specific formulations of AquaBlok® are available, including varieties that function in saline environments, incorporate treatment reagents to actively treat or sequester sediment contaminants, or contain plant seeds to promote the establishment or regrowth of vegetated habitat. The effectiveness of the product was evaluated over a 3-year period under EPA's SITE Program on sediments in the Anacostia River (Washington, DC), which is contaminated with PAHs, PCBs, and heavy metals. Overall results indicate that the material likely is more stable, more impermeable, and potentially more effective at controlling contaminant flux than traditional sand capping material, with similar impacts to benthos and benthic habitat.

Phytotechnologies

Phytoremediation Field Studies Database for Chlorinated Solvents, Pesticides, Explosives, and Metals
2004

This document was prepared by Ana Hoffnagle and Cynthia Green, two undergraduate students under internships with EPA. 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. The report includes process descriptions, site requirements, performance, process residuals, innovative systems, and EPA contacts for incineration, thermal desorption, chemical dehalogenation, solvent extraction, soil washing, solidification/stabilization, bioremediation, and vitrification.

This report was not subject to EPA peer review or technical review. EPA makes no warranties, expressed or implied, including without limitation, warranty for completeness, accuracy, or usefulness of the information.

The Use and Effectiveness of Phytoremediation to Treat Persistent Organic Pollutants
49 pp, Aug 2005

This document was prepared by Kristi Russell during an internship with the U.S. EPA, sponsored by the Environmental Careers Organization. This report is intended to provide an overview of phytoremediation uses to treat media contaminated by persistent organic pollutants and demonstrate the potential for use of phytoremediation in developing and transitional economies.

Soil Washing

Successful Field Scale Removal of PCB Soil Contamination at a Remote Former LORAN Station Site
Spengler, S.R., J. Silberman, D. Mead, M. Neal, R. Yamauchi, B. Balete, K. Duman, and A. Lutey.
Coast Guard Innovation Expo, October 25-27, 2011, Tampa, Florida. Poster presentation, 2011

At a dump area contaminated with PCBs from disposal of electrical equipment during former Coast Guard use of remote Kure Atoll (Northwest Hawaiian Islands), excavated soils were subjected to a series of soil washing and grain size separation treatments to develop an effective on-island means of treating PCB-contaminated material. The optimized process achieved 75 to 95% PCB removal.

Solvent Extraction

CF Systems Organics Extraction Process, New Bedford Harbor, Massachusetts. Applications Analysis Report
U.S. EPA, Superfund Innovative Technology Evaluation (SITE) Program.
EPA 540-A5-90-002, 73 pp, 1990.

Removal of PCBs from Contaminated Soil Using the CF Systems™ Solvent Extraction Process: A Treatability Study
Tillman, J., L. Drees, and E. Saylor.
U.S. EPA, Superfund Innovative Technology Evaluation (SITE) Program. EPA 540-SR-95-505, 8 pp, 1995.

Terra-Kleen Response Group, Inc., Solvent Extraction Technology, Innovative Technology Evaluation Report
U.S. EPA, Superfund Innovative Technology Evaluation (SITE) Program. EPA 540-R-94-521, 62 pp, 1998.

Stabilization

Evaluating the Efficacy of a Low-Impact Delivery System for In situ Treatment of Sediments Contaminated with Methylmercury and Other Hydrophobic Chemicals
Menzie, C., B. Amos, S.K. Driscoll, U. Ghosh, and C. Gilmour.
ESTCP Project ER-200835, 122 pp, 2016

Field demonstrations of in situ treatment of PCBs and mercury with activated carbon (AC) delivered using the SediMite(r) delivery system were conducted at two sites within Canal Creek at Aberdeen Proving Ground in Edgewood, Maryland. The application of SediMite to a third site--Bailey Creek at Fort Eustis in Virginia--is described for comparison along with data for a fourth site where SediMite was used to treat PCBs within a Phragmites (reed) marsh. PCBs bioavailability typically declined by >80% across these sites, with values >90% achievable. Efficacy was related to the presence of target doses of AC. Results were equivocal for treatment of mercury. Effects of treatment on native biota were judged to be negligible. Additional information: ESTCP Cost & Performance Report

Field Testing of Activated Carbon Mixing and In Situ Stabilization of PCBs in Sediment
ESTCP Project ER-0510, 288 pp, 2009

A field-scale project was conducted to demonstrate that activated carbon (AC) sorbent mixed with sediment is a cost-effective, nonremoval, in situ management strategy for reducing risk and the bioavailability of PCBs in offshore sediments at the Hunters Point Shipyard site. The demonstration also compared the effectiveness, in terms of AC application and ease of use, of two available large-scale mixing technologies. Uptake studies showed 50 to 66% reductions in PCB uptakes in AC-amended areas, depending on AC dose. Field-exposed AC retained a strong stabilization capability to reduce aqueous equilibrium PCB concentrations by as much as 95%, depending on AC dose, effective up to at least 18 months. See also the ESTCP Cost and Performance Report.

In Situ Treatment at PCB Contaminated Sediment Sites
Blackman, T., M. Martin, G. Braun, S. Ozkan, and E. Ashley.
Lockheed Martin Middle River Complex Feasibility Study Team, Project Note 2, 92 pp, 2013

Research and pilot studies on the in situ treatment of sediments by activated carbon application and its effectiveness for PCBs, PAHs, and metals stabilization indicate that in situ AC treatment is 75-95% effective for reducing PCBs and PAHs bioavailability. To provide background for future sediment remediation at the Middle River Complex site, located in Maryland , this project note presents a general description of in situ treatments, a brief review of ongoing research, and descriptions of projects and pilot studies where in situ treatments have been applied.

In Situ Wetland Restoration Demonstration: ESTCP Cost and Performance Report
Ruiz, N., J. Bleiler, K. Gardner, M. Johnson, T. Estes, D. Anders, and D. Barclift.
ESTCP Project ER-200825, 55 pp, 2014

The field demonstration was performed at Aberdeen Proving Ground, MD, to evaluate the ability of activated carbon (AC) to reduce PCB bioavailability and associated risks in Canal Creek wetland habitats using a variety of AC delivery systems: Powder-activated carbon slurry and two pelletized AC products, AquaBlok^® and SediMite^™. An engineered manufactured soil cover system provided the control. Each sequestration agent was mechanically deployed over the surface of a wetland and allowed to integrate into the surface layer of the hydric soil through natural mixing processes. The goal of this approach was risk reduction, not mass removal; however, while the findings of the overall program suggest that AC addition can sequester PCBs, the field demonstration findings were not conclusive in demonstrating effective reductions in bioavailability.

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.

Thermal Treatment: Ex Situ

Federal Remediation Technology Roundtable Technology Cost and Performance Reports

In-Pile Thermal Desorption of PAHs, PCBs and Dioxins/Furans in Soil and Sediment
Baker, R.S., J. LaChance, and G. Heron.
International Symposium and Exhibition on the Redevelopment of Manufactured Gas Plant Sites (MGP2006), April 4-6, 2006, Reading, England. 13 pp, 2006

In-Pile Thermal Desorption (IPTD) technology is an ex situ technology. The contaminated soil and/or sediment is are placed in covered piles interlayered with heater pipes and vapor extraction screens. The electrical heaters in the piles bring the temperature up to the target, typically around 330 degrees C for SVOCs, depending on the nature of the contaminants. The applied heat volatilizes both water and organic contaminants within the soil/sediment, and the vapors are carried in the air stream toward heater-vacuum extraction wells, where they are destroyed.

Minergy Corporation Glass Furnace Technology Evaluation
U.S. EPA, Superfund Innovative Technology Evaluation (SITE) Program, Washington, DC.
EPA 540-R-03-500, 137 pp, Mar 2004.
Contact: Marta Richards, richards.marta@epa.gov

Sangamo-Weston, Inc./Twelve Mile Creek/Lake Hartwell PCB Contamination Superfund Site, Pickens, Pickens County, South Carolina
U.S. EPA Region 4, Superfund Information System.

The land-based source areas of OU-1 include the Plant site and six satellite disposal areas, as well as contaminated groundwater associated with the land-based source areas. From December 1995 through May 1997, ~40,000 cubic yds of PCB-impacted material was removed from the satellite disposal areas and consolidated on the Plant site for treatment by low-temperature thermal desorption (to ~2 mg/kg PCBs) and then backfilled on site. Two pump-and-treat systems installed at the Breazeale and Plant sites collectively have recovered 215 million gallons of groundwater and removed 1,480 pounds of chlorinated solvents (mainly PCE and TCE) and 17.6 pounds of PCBs (primarily Aroclor 1248). In 2008, 9 pilot SVE wells were installed at suspected residual source areas on the Plant site, and their VOC removal efficiencies will be evaluated to determine if full-scale SVE is warranted. In 2007, pilot studies were implemented at the Breazeale site to evaluate ozone sparging and potassium permanganate as possible ISCO technologies to reduce the VOC plume. Based on the results, a ROD amendment was signed and full-scale ISCO using potassium permanganate was conducted in September 2009. SVE Pilot Study ISCO Pilot Study Sediment MNR.

Thermal Treatment: In Situ

Critical Evaluation of State-of-the-Art In Situ Thermal Treatment Technologies for DNAPL Source Zone Treatment
J.T. Kingston, P.R. Dahlen, P.C. Johnson, E. Foote, and S. Williams.
ESTCP Project ER-0314, 1,272 pp, 2010

The performance of thermal technologies for DNAPL source zone remediation was assessed with particular emphasis on post-treatment groundwater quality and mass discharge (i.e., mass flux). Documents from 182 applications were collected and reviewed—87 electrical resistance heating, 46 steam-based heating, 26 conductive heating, and 23 other heating technology applications—conducted between 1988 and 2007, with attention to the site geologic settings, chemicals treated, design parameters, operating conditions, and performance metrics. The results of the study are summarized in a set of spreadsheet-based summary tables linking this information to five generalized geologic scenarios. The Summary Tables identify generalized scenarios that can be used to anticipate the likely performance of thermal-based DNAPL treatment technologies at a site. Another product of this work, "State-of-the-Practice Overview of the Use of In Situ Thermal Technologies for NAPL Source Zone Cleanup," condenses the 1,000-plus pages of this report into an 86-page primer prepared for a program manager audience. State-of-the-Practice Overview

Demonstration of In-Situ Thermal Desorption-Destruction of PCB's in Contaminated Soils at Mare Island Shipyard. Technical Data Sheet
Lonie, C., J. Reed, G. Brown, and A. Evan, NFESC, Port Hueneme, CA.
NFESC-TDS-2051-ENV, NTIS: ADA361264, 5 pp, 1998.

Design: In Situ Thermal Remediation
U.S. Army Corps of Engineers. EM 200-1-21, 243 pp, 2014

This document provides guidance and background for the appropriate screening and selection of in situ thermal remediation technologies, including steam enhanced extraction/injection, electrical resistivity heating, and thermal conductive heating. The document is intended to help distinguish proper applications of the technology and identify important design, operational, and monitoring issues.

Federal Remediation Technology Roundtable Technology Cost and Performance Reports

In Situ Thermal Desorption (ISTD) of PCBs
Vinegar, H.J., et al.
HazWaste / World Superfund XVIII Washington, DC, December, 1997

A field demonstration of a new in situ thermal desorption soil remediation process (ISTD-Thermal Wells) was conducted at the Missouri Electric Works Superfund site in Cape Girardeau, Missouri, from April 21 through June 1, 1997. The technology is shown to remove high-concentration PCB contamination from clay soils.

Thermal Blanket for In-Situ Remediation of Surficial Contamination: A Pilot Test
Iben, I.E.T., W.A. Edelstein, R.B. Sheldon, A.P. Shapiro, E.E. Uzgiris, C.R. Scatena, S.R. Blaha, W.B. Silverstein, G.R. Brown, G.L. Stegemeier, and H.J. Vinegar.
Environmental Science & Technology 30(11):3144-3154(1996)

Surficial PCB contamination has been successfully and safely removed from soil in a field test at the site of a former dragstrip in Glens Falls, New York, where oil-containing PCBs had been sprayed to minimize airborne dust. Longer abstract

Thermal Conduction Heating for In-Situ Thermal Desorption of Soils
Stegemeier, G.L. and H.J. Vinegar.
Hazardous & Radioactive Waste Treatment Technologies Handbook, CRC Press, Boca Raton, Florida, Ch. 4.6-1, 51 pp, 2001

Compared to fluid injection processes, the conductive heating process is very uniform in its vertical and horizontal sweep. The heat dries and shrinks the soil, which renders it more permeable and improves transport of the vaporized contaminants, even in tight silt and clay layers. Because the entire treatment zone can be heated to high temperatures (in some cases, greater than 500 degrees C) for many days, the contaminants in the heated soil are almost completely removed. In practice, most of the contaminants are destroyed in the soil before reaching the surface. Contaminants that have not been destroyed in situ are removed from the produced vapor stream at the surface with an air pollution control system. Both thermal blankets and thermal wells have been proven to be highly effective in removing a variety of contaminants including PCBs, pesticides, chlorinated solvents, and heavy and light hydrocarbons.

In Buildings

Laboratory Study of Polychlorinated Biphenyl (PCB) Contamination and Mitigation in Buildings
U.S. EPA, Office of Research and Development, National Risk Management Research Laboratory, Research Triangle Park, NC.

Part 1. Emissions from Selected Primary Sources
EPA 600-R-11-156 Version 2, 127 pp, 2011
Part 2. Transport from Primary Sources to Building Materials and Settled Dust
EPA 600-R-11-156a Version 2, 166 pp, 2012
Part 3. Evaluation of the Encapsulation Method
EPA 600-R-11-156b Version 2, 108 pp, 2012
Part 4. Evaluation of the Activated Metal Treatment System (AMTS) for On-Site Destruction of PCBs
EPA 600-R-11-156c, 82 pp, 2012

EPA has conducted a series of studies in support of the main goal of mitigating PCB contamination in buildings, which is to reduce human exposure to PCBs caused by emissions from and contact with PCB sources.

Literature Review of Remediation Methods for PCBS in Buildings
U.S. EPA, National Risk Management Research Laboratory, Research Triangle Park, NC.
EPA 600-R-12-034, 68 pp, 2012

Based upon a comprehensive review and synthesis of conference proceedings and technical reports, this document offers a description and analysis of existing methods for management of PCBs in construction materials, with information (where available) on the strengths and limitations, efficacy, cost, and by-products of each remediation method. The report recommends the selection of remediation methods for each building on a case-by-case basis.

Steps to Safe Renovation and Abatement of Buildings That Have PCB-Containing Caulk
U.S. EPA website, 2012

The information on these Web pages is designed to assist building owners and abatement contractors who handle PCB-containing or PCB-contaminated building materials during planned renovation/repair activities or planned PCB abatement efforts in older buildings. The page has the following subsections: facts about PCBs in caulk; steps to safe renovation and repair activities; how to test for PCBs and characterize suspect materials; steps to safe PCB abatement activities; and a summary of suggested tools and methods for caulk removal.

Site-Specific Information

The U.S. EPA's Great Lakes Legacy Act Ashtabula River Clean-Up
Cieniawski, S.
U. S. EPA, Great Lakes Program Office, 46 pp (PPT), 2008

This is a PowerPoint presentation given to the U.S. EPA Technical Support Program's National Sediment Forum. It contains a novel treatment system for handling PCB contaminated hydraulic dredge produced sediments.

CLU-IN Site Profile Databases

CLU-IN Site Profile Databases contain information on thousands of projects where innovative approaches have been used to deal with contamination problems.

Completed North America Innovative Technology Demonstration Projects

Lists field demonstrations of innovative remediation technologies sponsored by government agencies working in partnership with private technology developers.

Federal Remediation Technology Roundtable Technology Cost and Performance Reports

FRTR makes available over 20 reports of cleanup technologies for PCB-contaminated sites.

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.

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

Polychlorinated biphenyls (pcbs)

Treatment Technologies