bluuebunny/crossref_metadata_2025 huggingface dataset:
The use of natural processes for the control of chromium migration
Authors: Chrostowski Paul C. , Durda Judi L. , Edelmann Kristen G.
Published: February 2007

Environmental contamination with ionic chromium has been identified as a problem at numerous Superfund and RCRA Corrective Action sites. In many cases, contamination of groundwater to levels above existing standards or criteria may be a potential problem both for direct consumption of groundwater and for transport of mobile forms of chromium to areas such as basements where it can becontacted. In the environment, chromium occurs in two forms: trivalent and hexavalent. The trivalent form is generally immobile and nontoxic; hexavalent chromium is generally mobile and toxic. This article first presents the extent of the chromium problem, reviews the environmental chemistry literature on chromium, and reviews existing treatment technology for chromium immobilization in the nontoxic trivalent state. Finally, we present a case study where immobilization of chromium occurred through natural processes allowing a modified no‐action scenario for site remediation.
The influence of soil composition on bioremediation of PAH‐contaminated soils
Authors: Middleton Andrew C. , Nakles David V. , Linz David G.
Published: February 2007

As a result of former industrial activities, many properties across the United States contain various chemicals in their soils at concentrations above background levels. Polynuclear aromatic hydrocarbons (PAHs) are often encountered at sites of gas manufacture, wood treating, tar refining, coke making, and petroleum reflning. When the presence of PAHs in site soil is deemed to create a situation of unacceptable risk to public health or the environment, treatment or disposal is required to reduce concentrations to acceptable levels.

The ideal remedial process for PAHs in soils would destroy them to an environmentally sound level at relatively low cost without producing adverse by‐products. In many cases bioremediation can accomplish these goals. The degree to which bioremediation can destroy PAHs in a particular soil, however, is highly dependent on the characteristics of that soil, including the nature of the hydrocarbon that is the source of the PAHs.

It is the objective of this article to describe efforts leading to this conclusion and to summarize how soil characteristics influence bioremediation of PAHs.
Selecting state‐of‐the‐art incinerators for complex aqueous wastes
Authors: Tischler JoAnn , Huenefeld Bruce , Irrgang Gene H.
Published: February 2007

The Rocky Mountain Arsenal (RMA) in Adams County, Colorado has been identified as a priority site on the Superfund National Priority List. The Program Manager's Office of RMA announced in early 1990 its intention to implement installation of a state‐of‐the‐art incineration plant to treat the most complex and controversial waste stream on the site.

Established in 1942, RMA served as an Army manufacturing center for chemical agents such as mustard gas, white phosphorus, napalm, and GB nerve agent. Parts of the site were also leased to Shell Oil Company, which manufactured pesticides and other agricultural chemicals at this location between 1952 and 1982.

To support these activities, the Army operated a ninety‐three‐acre surface impoundment called Basin F for collection and evaporation of chemical wastewaters. As a result of the wide variety of wastes received and concentrated at Basin F and early treatment attempts, its contents became one of the most unusual chemical cocktails known to man. By the time a formal interim response action for remediation was initiated in 1985, the composition of the Basin consisted of a multi‐phase fluid and sludge, including super‐saturated levels of inorganic salts; 30 percent or more organics such as pesticides, military agent by‐products, degradation products, and solvents; high levels of ammonia compounds and bound nitrogen; and percent levels of copper, arsenic, and other metals.

Selection of a remedial alternative involved twelve years of characterizationstudies and eleven years of treatability testing programs encompassing the universe of containment; encapsulation; stabilization; component separation; and thermal, electrical, chemical, and biological degradation technologies. The program resulted in the selection of a state‐of‐the‐art down‐fired liquid incinerator for destruction of aqueous organic contaminants in metallic salt matrices.

The treatability demonstration, and the technical justification for selection of the T‐Thermal submerged quench incinerator for this application, is the subject of this article.
Treating contaminated groundwater using a fluidized‐bed reactor
Authors: Hickey Robert F. , Wagner Daniel , Mazewski Gene
Published: February 2007

Both biological treatment and carbon adsorption have inherent advantages for remediation of groundwater contaminated with compounds such as benzene, toluene, ethylbenzene, and xylenes (BTEX). Biological treatment destroys the contaminants and is extremely cost‐effective. Carbon adsorption is a positive removal mechanism that ensures a product water of high quality, but the process is relatively expensive and requires frequent carbon replacement and/or regeneration. Coupling the two processes realizes the inherent advantages of both approaches. An additional benefit of combining these removal mechanisms in a biological fluidizedbed reactor (FBR) system is that no loss of BTEX from volatilization occurs, since predissolution of oxygen is used in place of conventional aeration for the fluidized‐bed process.

This article summarizes preliminary performance data from a laboratory, pilot‐scale biological FBR, using granulated activated carbon (GAC) as the support media (GAC‐FBR), operated at various BTEX concentrations and organic loading rates. Greater than 99‐percent degradation of total BTEX was achieved at an organic loading rate of 3.0 kg COD/m3‐day or less and an empty bed hydraulic retention time of 5.0 minutes. System performance was extremely robust, easily handling a tenfold step increase in loading due to the combined adsorptive capability of the biofilm‐coated GAC and ability to subsequently bioregenerate the GAC. Monitoring verified that no off‐gas was produced during treatment.
Immobilizing a light, nonaqueous phase liquid
Authors: Masters Eugene R. , Riggenbach Jack D. , Ammon Douglas C. , Sobel Richard
Published: February 2007

A new technique has been developed to immobilize organic chemicals at a Superfund site. In the course of predesign studies in preparing the Remedial Design for the Pioneer Sand Superfund site in Pensacola, Florida, a light, nonaqueous phase liquid (LNAPL) was discovered floating on the groundwater within the on‐site landfill. The liquid, with a viscosity similar to SAE 20 motor oil, was made up of heavy organic chemicals and volatile organic chemicals (VOCs), but no pesticides or polychlorinated biphenyls (PCBs). The volatiles present included toluene, ethylbenzene, and xylenes. Regulatory agencies expressed concern over the possibility of LNAPL migration and asked that a method of LNAPL immobilization be devised.
How to engineer biological processes that neutralize hazardous wastes
Authors: Bhattacharya Sanjoy K.
Published: February 2007

Because bioremediation must satisfy the fundamental biological tastes of specific organisms, environmental engineers must create a nutritious waste stew. Waste‐hungry organisms need a proper electron acceptor. Oxygen is preferred; if it is not available, nitrate, sulfate, or carbon dioxide may work. The waste itself is a source of carbon and energy. Macronutrients are next—including phosphorus, nitrogen, and certain metals, if they are not already present in the wastewater—as well as micronutrients. Other factors, including pH, temperature, aeration, and mixing must suit the organisms' natural temperaments. This article explores how bioengineers can combine these ingredients in precise quantities and proportions in both conventional and innovative aerobic and anaerobic bioprocesses, including in situ treatment and even composting, to make the organisms healthy, happy, and inexpensive.
Look at groundwater quality to set VOC cleanup levels
Authors: Rosenbloom Jeff , Mock Peter , Turin H. J. , Lawson Peter , Brown Jess
Published: February 2007

In 1981, the Arizona Department of Health Services (ADHS) discovered groundwater contamination by solvents and chromium at the Phoenix Goodyear Airport (PGA), just outside the city of Phoenix. ADHS and the U.S. EPA sampled the site for the next two years, finding that eighteen of their wells were contaminated with trichloroethene (TCE), six exceeding ADHS's action level of five micrograms per liter (μg/l). In 1983, the PGA site was added to the National Priorities List, and, in 1984, EPA began a $3 million remedial investigation, focusing on soils and groundwater. This article discusses how that investigation inspired the authors to develop a stream‐lined evaluation method for PGA's volatile organic compounds (VOCs), the process for establishing VOC cleanup levels, and the $26 million of remediation work needed to be done at the site. The heart of this effort is a computer program called VLEACH, loosely standing for VOC‐LEACHing, which anticipates the influence of VOCs on PGA's groundwater, even as remediation proceeds.
Telerobots for remote disposal of mixed waste
Authors: Yemington Charles R. , Stone James E.
Published: February 2007

Two remote‐controlled robotic submersible vehicles and an automated shredder are helping remove and dispose of highly reactive, sometimes explosive materials, dumped into a water‐filled quarry at the U.S. Department of Energy's reservation in Oak Ridge, Tennessee. Human workers never enter the four‐acre site, except for well‐planned equipment maintenance and to shoot holes from a protected but into the retrieved containers, releasing pressure and exposing the contents to air and water. During its approximately two years of operation, the $8 million project has retrieved more than 15,000 items from the thirty feet of water at the bottom of the quarry.
Effects of cosolvency in the fate and transport of PCBs in soil
Authors: Haasbeek John F.
Published: February 2007

Under the purview of EPA's Remedial Engineering Management (REM III) Superfund contract, a CERCLA RI/FS was performed at the Pinettes Salvage Yard site located in Washburn, Maine (EPA Region I). The purpose of the RI/FS was to fully characterize the nature, extent, and fate and transport of PCB contamination resulting from an alleged surface spill of transformer dielectric fluid containing Arochlor 1260 (a polychlorinated biphenyl) and various volatile and semivolatile organic constituents. The RI/FS was performed subsequent to both an immediate removal action (IRA) and a deletion remedial investigation (DRI) performed by EPA contractors. Results of both efforts indicated that the site was unsuitable for deletion from the National Priorities List (NPL) because the site soils contained elevated levels of PCBs.

This article presents a case history of the extensive field investigations performed to characterize the contaminant source and evaluate the fate and transport of PCBs in site soils. These investigations included on‐site mobile laboratory gas chromatograph (GC) analytical techniques for PCBs and targeted volatile and semivolatile organic compounds; confirmatory Contact Laboratory Program (CLP) laboratory analyses of soils, sediments, surface water, and groundwater samples; statistical analyses and correlation of field mobile laboratory GC data with CLP laboratory analytical results; and an evaluation of the potential effects of cosolvency in the fate and transport of PCBs in subsurface soils.
A conceptual study on the bio‐wall technology: Feasibility and process design
Authors: Yang Xiaoqing , Fan L. T. , Erickson Larry E.
Published: February 2007

In‐situ bioremediation is a process by which contaminants in subsurface environments are biologically eliminated or mineralized; however, it is often difficult to implement. Microbes sparsely distributed in deep soils are incapable of degrading a chemical rapidly; furthermore, fine‐pore structures of soils tend to retard the penetration and propagation of these microbes and hinder oxygen transfer. The latter is particularly detrimental to the aerobic growth of microbes, which is often essential for bioremediation. Measures intended to promote bioremediation, such as the addition of surfactants for enhancing dissolution and the application of genetically engineered microbes for accelerating the biodegradation of contaminants, are almost impossible to adopt. This is attributable to the fact that various facets of the bioremediation process (e.g., the distribution of dissolved contaminants, nutrients, and oxygen, and the concentration of microbes) cannot be readily manipulated.

This article proposes a novel technology, namely, bio‐wall. This technology resorts to an in‐situ constructed medium with porosity and organic content greater than those of the original soil for promoting the adsorption and retention of microbes and the biodegradation of contaminants. Moreover, oxygen and nutrients are supplied to the bio‐wall to facilitate microbialgrowth. The results of conceptual design study and simulation have revealed that the technology is indeed feasible and, under certain environmental conditions, cost‐effective. Particularly noteworthy is the fact that bio‐wall can prevent contaminant migration through the enhancement of the biodegradation rate and reduction of the plume‐distance, both by several orders of magnitude.
Choosing the most effective hazardous waste landfill cover
Authors: Warren Ronald W. , Hakonson Thomas E. , Bostick Kenneth V.
Published: February 2007

Determining the appropriate criteria and designs for hazardous waste landfill covers has spawned much discussion within the environmental remediation arena. Very little reliable comparison of various technologies exists. Researchers at Los Alamos National Laboratory studied the relative hydrologic performance of four landfill cover designs—two capillary barrier designs, one modified EPA RCRA design, and one control cover. Monitoring the fate of natural precipitation for nearly four years showed that the covers with barrier layers more effectively reduced deep percolation than the control cover. Although none entirely eliminated deep percolation, the RCRA cover, incorporating a clay hydraulic barrier, most effectively controlled it. The two capillary barriers reduced deep percolation, but significant amounts were still produced. Over 90 percent of all percolation through the covers, and lateral flow within the covers, occurred during February through May each year, primarily as a result of snowmelt, early spring rains, and low evapotranspiration. The study also showed that gravel mulch surface treatments (70‐ to 80‐percent ground cover) reduced runoff and erosion. Despite additional shrubs planted on one, the two plots receiving the gravel mulch treatments exhibited equally enhanced amounts of evapotranspiration.
In‐situ biological treatment of vinyl acetate‐contaminated soil: An emergency response action
Authors: Flathman Paul E. , Krupp Bryon J. , Zottola Paul , Trausch Jason R. , Carson John H. , Yao Ruji , Laird Gregory J. , Woodhull Patrick M. , Jerger Douglas E. , Lear Paul R.
Published: February 2007

In‐situ biological solid‐phase (or land) treatment was cost‐effectively used to remediate 1,500 cubic yards (1,100 m3) of contaminated soil within three months of field operation following spillage of an estimated 12,000 gallons (45,000 L) of vinyl acetate from a railroad tank car onto surface soil. The vinyl acetate rapidly hydrolyzed to acetate and acetaldehyde with concentrations ranging up to 22,000 and 3,000 mg/kg, respectively. Ethanol, a metabolic intermediate, was found to accumulate in soil to concentrations as high as 280 mg/kg. The estimate for excavation, transportation, and disposal of the contaminated soil as a special waste, and for backfilling of the excavated area, was $850,000. The cost for biological remediation of the contaminated soil was $400,000, which was less than half the cost of excavation. In‐situ biological treatments have been used to readily remove contaminants, such as acrylonitrile, styrene, butylcellosolve, ethylacrylate, and n‐butylacrylate, at other sites involving railroad incidents.
Fast‐track remediation for redevelopment of a former integrated steel mill site
Authors: Lister Kenneth H.
Published: February 2007

Remedial action was initiated and completed on an approximately 500‐acre brownfield site in southern California within a period of five months during the summer of 1995. Remedial actions included design and construction of an approximately 14‐acre cap, including a synthetic membrane; design, construction, and testing of an in‐situ soil vapor extraction system; excavation, on‐site treatment, and off‐site disposal of approximately 7,000 cubic yards of residual waste and affected soil; and verification sampling, analysis, and health risk screening in 20 units of a former integrated steel mill. Completion of remedial action on this portion of the mill site within this time frame was required due to site redevelopment plans which included construction of an auto raceway with scheduled races in early 1997. Rapid remedial action was possible only through simultaneous completion of multiple remediation tasks. This could be done only with continuous communication and close coordination among the site owner, lead regulatory agency, and contractors.
Enhanced intrinsic bioremediation of hydrocarbons using an oxygen‐releasing compound
Authors: Odencrantz Joseph E. , Johnson Jeffrey G. , Koenigsberg Stephen S.
Published: February 2007

An “oxygen barrier” was formed by depositing an oxygen‐releasing compound in a series of wells that were placed perpendicular to the direction of groundwater flow at a site in Belen, New Mexico. The objective was to enhance the intrinsic bioremediation of dissolved phase BTEX contamination in the aquifer and to quantify the results. The oxygen was supplied by a controlled release formulation of magnesium peroxide called Oxygen Release Compound (ORC®), a virtually insoluble powder that is packaged in polyester filter socks. The areal distributions of the initial concentrations of dissolved oxygen and BTEX were measured and compared to the concentration changes at various times in the first 93 days of system operation. The concomitant reduction in BTEX can be seen in a series of contour plots. In 93 days, dissolved oxygen had dispersed at least 20‐feet downgradient from the ORC source wells based on the pattern of decreasing BTEX concentrations.
Phytoremediation: Modeling removal of TNT and its breakdown products
Authors: Medina Victor F. , McCutcheon Steven C.
Published: February 2007

Contamination of soil and groundwater by trinitrotoluene (TNT) is a widespread problem confronting military bases and ammunition manufacturing facilities throughout the United States. Phytoremediation provides a promising treatment of TNT‐contaminated groundwater and wastewater because many plants contain the necessary enzymes to degrade explosives such as TNT. Two phytoremediation methods are proposed in this article: controlled reactors and constructed wetlands. Controlled reactors provide greater control of operating parameters, a reduced possibility of contaminant migration, control of animals feeding on the plants, and minimization of competition from other plant species. Constructed wetlands have relatively low capital costs, and the wetland becomes a desirable ecological resource. Because cost, as opposed to reactor size, appears to be the most significant factor for military base cleanup, this project focused on the constructed wetland approach.

To estimate the disappearance of TNT and its breakdown products from a constructed wetland, a first‐order, nonreversible reaction, plug‐flow, finite‐difference model was developed. Batch scale experiments were conducted to define disappearance kinetics for individual chemical species. The results of the model suggest that reasonably sized wetlands may be used to treat a wastestream with an influent TNT concentration of 2.25 ppm at flow rates ranging from 10 to 5,000 gpm. Economic comparisons to other published costs for competing technologies are promising.
Primer on GRITS/STAT 5.0
Authors: Kimzey Doug
Published: February 2007

GRITS/STAT 4.2 (Groundwater Information Tracking System with statistical analysis capability) enjoys widespread use in the groundwater community. GRITS/STAT is a free PC‐based database system capable of performing many of the statistical methods promulgated by the EPA guidance documents: Statistical Analysis of Ground‐Water Monitoring Data at RCRA Facilities, 1989, and Addendum to Interim Final Guidance, 1992. GRITS/STAT 4.2, however, suffered from numerous software problems and lagged behind current guidance, particularly in the implementation of statistical intervals. With the release of GRITS/STAT 5.0, many of the software problems that plagued GRITS/STAT 4.2 were addressed and an entirely new Statistical Intervals module was added to bring the software closer to current guidance. The GRITS/STAT 5.0 Beta Test produced a helpful list of work arounds to commonly reported problems. A comparison of the Parametric Confidence Interval methods in GRITS/STAT 4.2 and GRITS/STAT 5.0 illustrates the expanded utility offered by the new Statistics module. The Parametric Confidence Interval in GRITS/STAT 4.2 is only moderately useful for comparing individual wells to an alternate concentration limit (ACL) computed on average background samples. GRITS/STAT 5.0, however, offers users the ability to compare individual and pooled wells to ACLs computed on background averages and risk‐based maximum concentration limits (MCLs).
The trade‐off between assessment and cleanup phases of remediation projects
Authors: Painter Jennifer P. , Hogan Brian J.
Published: February 2007

Based on actual project experiences over the past decade, execution strategies for remediation projects have varied significantly. For example, the overlap between the assessment and cleanup phases can range from none (for projects that complete assessment activities before starting the cleanup) to almost half of the assessment duration (for projects that may be under pressure to show progress at the site). This article quantifies the relationship between remediation project execution strategies, project definition components, and remediation project cost and schedule performance. By relating project outcomes to indicators that can be monitored early in the project cycle, project teams may be able to correct problems before they affect the ultimate performance of the remediation project.
Best management practices to prevent cross‐media transfers during soil cleanup
Authors: Dutta Subijoy , Robinson Bonnie B.
Published: February 2007

Cleanup activities often focus on the initial and final concentration levels of contaminants. What happens in‐between, during implementation of treatment technologies, has raised major concerns by several environmental groups. To address this issue, the U.S. Environmental Protection Agency (EPA) has undertaken the task of developing a guidance that would identify the potential for cross‐media transfer during implementation of various soil treatment technologies and recommend best management practices (BMPs) to prevent or control these cross‐media transfers. The soil treatment technologies have been grouped into seven major categories in this effort. This article provides some details of the seven soil treatment technology groups and the general BMPs recommended in the draft BMP guidance document. One case history of existing control practices is also presented in this article and compared with the recommended BMPs.
Enhanced land treatment of petroleum‐contaminated soils using solid peroxygen materials
Authors: Davis John W. , West Robert J. , Klecka Gary M.
Published: February 2007

A pilot field study evaluated whether adding solid peroxygen materials during land treatment could cost effectively accelerate cleanup at a site contaminated with petroleum‐related compounds. Five test cells were constructed containing approximately five cubic yards of soil contaminated with 300–400 mg/kg of total petroleum hydrocarbons (TPH). Three cells received treatment with solid peroxygen materials (either MgO2 or CaO2), while the other two cells served as controls (no peroxygen amendment). Adding solid peroxygen compounds effectively reduced the hydrocarbon contamination in the soils and decreased the treatment time. During this time, the concentration of TPH in soil in the three treatment cells decreased. In contrast, there was little loss of TPH from the two control cells simulating traditional land treatment. Adding the solid peroxygen materials reduced the total site remediation time, thereby reducing the overall costs.
Rehabilitation of the chernoistochinskii drinking water system, Nizhnii Tagil, Russia
Authors: Brown James R. , Myers Vernon B. , Parker Susan G. , Stewart Robert
Published: February 2007

The U.S. Environmental Protection Agency (EPA) performed a reservoir diagnosis and developed low‐cost recommendations to improve drinking water quality for the city of Nizhnii Tagil, Russia. Despite widespread regional pollution, water quality within the drinking water supply source can be summarized as generally good. Sampling and analysis efforts did not reveal appreciable amounts of hazardous chemicals or metals. The major water quality problem stems from an abundance of blue‐green algae during the summer months, causing drinking water taste and odor problems and filter clogging at the water treatment plant. City water treatment officials also frequently experience difficulties with maintaining an effective disinfection residual in the distribution system because it spans more than 30 kilometers in length. Regrowth of microorganisms in the distribution system often causes coliform bacteria counts to exceed standards. The implementation of a watershed protection and management program, and the installation of a new disinfection system, to purify drinking water and to reduce bacterial growth in the distribution system should improve drinking water quality for the city residents.
A risk assessment of chlorinated aliphatics in bioremediated soils
Authors: Smith Tracy G. , Portier Ralph J.
Published: February 2007

Natural microbes living in contaminated subsurface media can be enhanced to degrade large concentrations of contaminating compounds at a faster rate than the microbes could degrade under natural conditions. A feasibility study demonstrating this principle was performed on‐site in southern Louisiana to evaluate the effectiveness of two microbial degradation remediation methods used to decrease the human carcinogenic risks associated with exposure to ethylene dichloride and vinyl chloride concentrations in contaminated clay and sludge soils at the site. The results of the study are compared to an acceptable Louisiana Department of Environmental Quality closure level to evaluate in‐situ microbial enhancement in chlorinated aliphatic‐contaminated sludge and clay soils as a remediation/cleanup alternative in similar industrial situations.
Adaptive sampling and analysis programs for contaminated soils
Authors: Johnson Robert , Quinn John , Durham Lisa , Williams Gustavious , Robbat Albert
Published: February 2007

Adaptive sampling and analysis programs (ASAPs) provide a cost‐effective alternative to traditional sampling program designs. ASAPs are based on field analytical methods for rapid sample turnaround and field‐based decision support for guiding the progress of the sampling program. One common objective of ASAPs is to delineate contamination present in soils, either to support feasibility studies or remedial action designs. An ASAP based on portable gas chromatograph/ mass spectrograph (GC/MS) technologies developed at Tufts University combined with decision support tools created at Argonne National Laboratory was used to delineate explosives contamination in soils at Joliet Army Ammunition Plant, Joliet, Illinois. Tufts' GC/MS technologies provided contaminant‐specific identification and quantification with rapid sample turnaround and high sample throughput. Argonne's decision support tools estimated contamination extent, determined the uncertainty associated with those estimates, and indicated where sampling should continue to minimize uncertainty. In the case of Joliet, per sample analytical costs were reduced by 75 percent as compared to the cost of off‐site laboratory analyses for explosives. The use of an ASAP resulted in a much more accurate identification and delineation of contaminated areas than a traditional sampling program would have with the same number of samples collected on a regular grid. While targeting explosives contamination in soils at Joliet, the ASAP technologies used in this demonstration have much broader application.
Thermal treatment and decontamination of mercury‐contaminated waste: Recent developments and comparative evaluation
Authors: Sadhukhan Pasupati , Bradford Mike
Published: February 2007

The land disposal restriction regulations have necessitated development of technologies for the treatment of wastes and soils containing mercury. Of all the treatment methods, thermal technologies are the most advanced and proven for a variety of mercury‐contaminated waste materials.

During the past few years, a number of thermal treatment processes have been developed both for listed and characteristic waste. A review of the technologies identified six that are in either commercial or pilot plant stages. The biggest volumes of waste currently occur in the gas processing and caustic‐chlorine industries, so most of the technologies being used appear to have been developed around the characteristics of these two wastes.

This article discusses the characteristics of each of the six available thermal treatment processes, and describes the types of mercury‐contaminated wastes these technologies have been designed to handle.
Natural biodegradation of wood preservatives
Authors: Stroo Hans , Cosentini Chris , Ronning Tedd , Larsen Mark
Published: February 2007

Natural biodegradation can contain groundwaters impacted by creosote and pentachlorophenol. Using natural biodegradation for such sites is attractive because groundwater restoration is often impracticable, but the dissolved plumes are biodegradable and exert relatively low oxygen demands. Three case studies of its successful use are presented, with emphasis on the types of evidence needed, the rates and extents of removal, and the strategies for incorporating natural biodegradation into a remediation approach. Natural biodegradation was proven at all three sites, using a combination of field geochemical measurements, laboratory simulations, and computer modeling. Contaminant plumes at these three sites were contained within 100 to 700 feet downgradient of the apparent sources, although the rates of biodegradation varied widely. Natural biodegradation should be considered as part of an overall remedial strategy for most sites contaminated by creosote and/or pentachlorophenol.
Implications of MTBE for Intrinsic Remediation of Underground Fuel Tank Sites
Authors: Odencrantz Joseph E.
Published: February 2007

MTBE in groundwater has been shown to travel over 1,000 feet downgradient from its source in several comprehensive field studies conducted across North America. The biodegradability of MTBE is examined by summarizing all the significant literature on the subject and by detailing the findings of recent field investigations of MTBE transport. In Orange County, California, the persistence of MTBE is analyzed and statistical representations of source variability are presented. Regional and far field transport of MTBE in groundwater sourced from underground gasoline storage tanks are summarized in comprehensive tables of frequency and plume length. Estimates of source mass and duration allow for comparison of associated plume size. The conclusion reached after reviewing all the available literature on MTBE is that its biodegradability seems slight and the size of the plumes are surprisingly large. Intrinsic or natural attenuation remedies for MTBE merit close scrutiny.
SITE Program Success: Cost Savings to Government and Increased Revenue for Technology Vendors
Authors: Gatchett Annette M. , Edwards Katherine S.
Published: February 2007

The Superfund Innovative Technology Evaluation (SITE) program is a program mandated by Congress through the 1986 Superfund Amendments and Reauthorization Act (SARA). The original Superfund allowed no provisions for research and development of needed remediation technologies. Problems arose when the demand for involved, complex treatment could not be met by the traditional contain, haul, and dispose process that hazardous waste handlers had become familiar with. In response to the increasing complexity of hazardous waste site remediation, SARA called for an “Alternative or Innovative Treatment Technology Research and Demonstration Program.” As a result, EPA's Office of Solid Waste and Emergency Response and the Office of Research and Development established the SITE program. This article is a historical analysis of the unique cost savings of the SITE program.
Powerful data analysis routine helps locate buried bombs
Authors: Barthel Christian , Rosenberger Ralf
Published: February 2007

Heavy bombing during World War II in Europe, particularly in Germany, left thousands of unexploded bombs buried underground and underwater. The bombs can be detected with magnetic sensors, but sorting through the huge amounts of data generated in area searches has proven to be by far the most difficult part of the task. Recently, a data analysis program has been developed that is capable of correlating global positioning system (GPS) data to magnetic sensor readings to identify likely bomb site candidates in a remarkably short period of time. A key to the success of this application is the use of packaged data‐analysis software, Origin, from Microcal Software, Inc. (Northampton, Massachusetts), which is capable of interfacing to external C and C++ pattern curve‐fitting routines that operate at the required high rates of speed.
A planning‐level model for estimating quantities of wastes generated by the demolition of structures during remediation
Authors: Davis Michal J.
Published: February 2007

A model is presented to estimate quantities of wastes generated by the demolition of various types of industrial structures. It is intended to be used for preliminary planning purposes in the absence of any detailed structure‐specific information. Detailed material quantity estimates compiled for structures at the U.S. Department of Energy's Fernald site in Ohio were used to develop the statistical relationships in the model. The model provides estimates of the total quantity of wastes, the quantities of waste concrete, and the quantities of wastes that originate from at‐, below‐, and above‐grade portions of a structure.
A local solution to superfund clean‐up: The southeast rockford site
Authors: Morrissette Peggy
Published: February 2007

On January 13, 1999 a consent decree was signed for the first community settlement ever successfully negotiated for a Superfund site. The 10‐square mile groundwater study zone in Rockford, Illinois, is only 20 percent of the area of the city, but represents 60 percent of its industrial capacity. Local government and business leaders took the initiative to negotiate a community‐based settlement with the United States Environmental Protection Agency (EPA) and the Illinois Environmental Protection Agency (IEPA) and find financing mechanisms that citizens could back.

Rockford dodged the Superfund bullet that has ripped apart so many other communities as bank loans dry up, development ceases, local taxes plunge along with property values, the local economy stagnates, and neighbor is pitted against neighbor in a litigation war.
Use of open‐path FTIR spectroscopy to address air monitoring needs during site remediations
Authors: Minnich Timothy R. , Scotto Robert L.
Published: February 2007

Although open‐path Fourier‐transform infrared (FTIR) spectroscopy has been an Environmental Protection Agency (EPA) Toxic Organic Compendium Method since 1996, it has been underutilized as a means to assess exposure to gaseous contaminants during the remediation of hazardous waste sites. This might be considered surprising in light of the many benefits that proper application of this technology can offer. In this article, we provide an overview of the technology and the principle of operation, describe the nature of the data generated, discuss the benefits associated with the technology's use in site clean‐up, present emission‐rate estimation techniques, and examine the reasons why it has not gained more support over the years. Finally, we present a case study in which the technology was used to drive an 11‐month emergency removal action under the direction of the U.S. Environmental Protection Agency.
A performance history of the base catalyzed decomposition (BCD) process
Authors: Schupp Donald A. , Krishnan E. Radha , Huffman George L.
Published: February 2007

Remediation of halogenated organic compounds—such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo‐p‐dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs)—poses a challenge because these compounds are resistant to microbial attack and to degradation by many common chemicals. Since the mid‐1980s, the Environmental Protection Agency's (EPA's) Office of Research and Development in Cincinnati, Ohio—the National Risk Management Research Laboratory (NRMRL)—has funded research and development efforts to develop specialized, chemical dehalogenation processes for detoxifying PCBs and related compounds. NRMRL owns domestic rights for “basic process” patents on a chemical dehalogenation process commonly known as Base Catalyzed Decomposition (BCD). EPA has licensed the process to two firms for use in the United States. This article summarizes laboratory‐scale, pilot‐scale, and field performance data on BCD technology collected to date by various governmental, academic, and private organizations.
Dynamic workplans and field analytics: Metals assessment by inductively coupled plasma/optical emission spectroscopy
Authors: Simpson Robert L. , Bock Christa L. , Robbat Albert
Published: February 2007

Hazardous waste site investigations were carried out at the Marine Corps Air Station (MCAS) in Yuma, Arizona and at Hanscom Air Force Base (HAFB) in Bedford, Massachusetts. The purpose of the first was to determine the location and extent of metals contamination throughout the base. The objective of the second was to evaluate the risk of metals contamination to groundwater from soil at three locations within the airfield. Dynamic workplans were developed and an adaptive sampling and analysis plan carried out with the data produced in the field used to support the goals of each project. An inductively coupled plasma/optical emission spectrometer (ICP/OES) was modified for field operation. A more efficient microwave digestion method and pressurized Teflon filtration system were developed for the HAFB project. Results were comparable to standard Environmental Protection Agency (EPA) methods, which must rely on two digestion procedures to recover EPA‐targeted metals within the prescribed recovery range. The MCAS investigation, conducted over a five‐month period, advanced the Navy's efforts from 30 months behind schedule to 18 months ahead of schedule, while the data generated at HAFB showed no risk to groundwater from metals.
Six‐phase heating™: The new power tool
Authors: Kendall Scott , Wolf Jerry L.
Published: February 2007

The removal of dense non‐aqueous phase liquids (DNAPL) in‐situ remains one of the remediation industry's toughest burden. Numerous treatment methods have been applied in an effort to deal with this problem, most requiring many years of continued application to produce even marginally successful results. Current Environment Solutions (CES) has brought a new technology, known as Six‐Phase Heating™ (SPH), to bear on this problem. This new technology is proving capable of providing rapid remediation of DNAPL‐contaminated sites at reasonable costs.
Bench‐ and pilot‐scale applications of electrochemical peroxidation: A new remedial concept
Authors: Chiarenzelli Jeffrey , Falanga Lauren , Wunderlich Michele
Published: February 2007

Electrochemical peroxidation (ECP) is a proprietary process that utilizes sacrificial iron electrodes and stochiometrically balanced applications of hydrogen peroxide to efficiently destroy aqueous phase contaminants. In laboratory trials it has been successful in reducing, often to non‐detectable levels, BTEX, fuel additives, chlorinated solvents, and polychlorinated biphenyls in ground waters. The process has also been found effective in reducing the chemical and biological oxygen demand of industrial waste water. Agency‐approved pilot tests will be conducted at two gasoline spill sites during 2000 where traditional pump and treat methods have proven ineffectual because of ground water chemistry or subsurface hydrologic conditions. The ECP process utilizes a tripartite treatment strategy consisting of 1) ex situ chemical oxidation; 2) in situ oxidation by reinjection of treated water with residual oxidants at the head of the plume; and 3) reestablishment of aerobic biodegradation by alteration of subsurface redox conditions. In contrast to other in situ oxidation treatment methods, dissolved iron is derived electrochemically, negating the need for ferrous salt addition. Dilute hydrogen peroxide (3 percent) is incrementally added to maximize oxidation efficiency and eliminate safety and environmental concerns accompanying the use of highly concentrated solutions. Results of laboratory trials and the geological and geochemical considerations of upcoming pilot‐scale applications are presented. Other potential applications currently under investigation include combination with other remedial processes (e.g. permeable barriers and hydrogen release compounds) to insure complete and rapid contaminant mineralization.
Superfund cleanup: Designing containment remedies for recreational reuse
Authors: King Joseph D. , Taylor Richard J. , McLaughlin Andrea , Voss Christopher
Published: February 2007

In July, 1999, EPA announced its Superfund Redevelopment Initiative, the Agency's effort to help communities bring Superfund sites back into productive use in a manner that is protective of human health and the environment. As part of the Superfund Redevelopment Initiative, the Agency is developing reuse design guides that provide technical information related to the design of remedies that safely support reuse. The design guides focus on the reuse of containment sites, and address such topics as settlement, gas control, irrigation, drainage, and operation and maintenance. Case studies of redeveloped sites are also presented in the guides. EPA is currently developing design guides that address the reuse of Superfund sites for commercial purposes, wildlife areas, parking lots, recreational sports fields, and golf courses. This article provides information on the first guide in the series‐the reuse of Superfund sites for recreational purposes.
Cyclodextrin‐enhanced remediation of organic and metal contaminants in porous media and groundwater
Authors: Boving Thomas B. , McCray John E.
Published: February 2007

Heavy metals and toxic organic contaminants are found at numerous industrial and military sites. The generally poor performance of conventional pump‐and‐treat schemes has made the development of improved methods for contaminated site remediation a significant environmental priority. One such innovative method is cyclodextrin‐enhanced flushing of the contaminated porous media and groundwater. Cyclodextrin is a glucose‐based molecule that is produced on industrial scales by microorganisms. Over the last years, several cyclodextrin derivatives have received extensive research interest. It was shown that cyclodextrins can significantly enhance the solubility of toxic organics, and in some cases, heavy metals and radioactive isotopes. As a sugar, cyclodextrin is considered relatively non‐toxic to humans, plants, and soil microbes. Thus, there are minimal health‐related concerns associated with the injection of cyclodextrin into the subsurface, which is an inherent advantage for use of cyclodextrins as a remediation agent. This paper provides a review of the available literature concerning use of cyclodextrin for remediation of groundwater and soil.
Evaluation of a vertical frozen soil barrier at oak ridge national laboratory
Authors: Lynn Stanley W. , Rock Steven , Rhodes Carl
Published: February 2007

Arctic Foundations, Inc. (AFI), of Anchorage, Alaska, has developed a freeze barrier system designed to hydraulically isolate a contaminant source area. The system can be used for long‐term or temporary containment of groundwater until appropriate remediation techniques can be applied. The technology was evaluated under the United States Environmental Protection Agency's (EPA's) Superfund Innovative Technology Evaluation (SITE) program at the United States Department of Energy's (DOE's) Oak Ridge National Laboratory (ORNL) facility in Oak Ridge, Tennessee. For the demonstration, an array of freeze pipes called “thermoprobes” was installed to a depth of 30 feet below ground surface around a former waste collection pond and keyed into bedrock. The system was used to establish an impermeable frozen soil barrier to hydraulically isolate the pond. Demonstration personnel collected independent data to evaluate the technology's performance. A variety of evaluation tools were used—including a groundwater dye tracing investigation, groundwater elevation measurements, and subsurface soil temperature data—to determine the effectiveness of the freeze barrier system in preventing horizontal groundwater flow beyond the limits of the frozen soil barrier. Data collected during the demonstration provided evidence that the frozen soil barrier was effective in hydraulically isolating the pond.
Simultaneous determination of volatile and semivolatile organic compounds in soil
Authors: Mauro David M.
Published: February 2007

A microscale solvent extraction (MSE) method was developed for the simultaneous determination of volatile organic compounds (VOCs) and semivolatile organic compounds (SVOCs) in soil. Tests of precision, recovery, and comparability to other Environmental Protection Agency (EPA) methods have been completed, and the MSE method compares well to Soxhlet and sonication extraction. Based on these validation data, EPA has assigned number 3570 to this method. Method 3570 has several advantages, including reduced use of solvent and soil sample, generating much less laboratory waste. Laboratory space and labor requirements are reduced as compared to many other sample preparation methods. Consequently, Method 3570 can provide comparable chemical data at less cost or environmental impact.
Aerobic Cometabolism of Halogenated Aliphatic Hydrocarbons: A Technology Overview
Authors: Saul Michael T.
Published: February 2007

Bioremediation of chlorinated solvents has been moving from an innovative to mainstream technology for environmental applications. Cometablism of chlorinated solvents by monooxygenase has been demonstrated for trichloroethylene (TCE). Cl‐out microbes combine the dehalogenation of PCE with the monooxygenase destruction of TCE to complete the PCE breakdown pathway. Underthe right conditions, cometabolic bioremediation can be cost effective, fast, and complete. Aerobic bioremediation can augment mass transfer technologies such as pump and treat or sparging/vapor extraction to improve their efficiency.