U.S. Army Engineer Research and Development Center (ERDC) Solicitation W912HZ10BAA01, 15 Jan 2010

The ERDC has issued a Broad Agency Announcement (BAA) for various research and development topic areas. The ERDC consists of the Coastal and Hydraulics Lab, the Geotechnical and Structures Lab, the Environmental Lab, and the Information Technology Lab in Vicksburg, Mississippi; the Cold Regions Research and Engineering Lab in Hanover, New Hampshire; the Construction Engineering Research Lab in Champaign, Illinois; and the Topographic Engineering Center in Alexandria, Virginia. The ERDC is responsible for conducting research in the broad fields of hydraulics, dredging, coastal engineering, instrumentation, oceanography, remote sensing, geotechnical engineering, earthquake engineering, soil effects, vehicle mobility, self-contained munitions, military engineering, geophysics, pavements, protective structures, aquatic plants, water quality, dredged material, treatment of hazardous waste, wetlands, physical/mechanical/chemical properties of snow and other frozen precipitation, infrastructure and environmental issues for installations, computer science, telecommunications management, energy, facilities maintenance, materials and structures, engineering processes, environmental processes, land and heritage conservation, and ecological processes. The BAA is open until superseded, which will be approximately January 31, 2011. Proposals can be accepted at any time. https://www.fbo.gov/spg/USA/COE/329/W912HZ10BAA01/listing.html

Environmental Management Engineering and Technology Highlights, p 2-3, Sep 2009

With support from DOE's Office of Deactivation and Decommissioning and Facility Engineering, Cellular Bioengineering, Inc. (CBI) has developed and demonstrated several decontamination gels (DeconGel™ 1101, 1120, and 1121) to remove/reduce radionuclides from building and equipment surfaces. With this method of removing radioactive contamination, doses of radioactivity to workers and disposal costs can be reduced. The hydrogel coating can be applied to horizontal, vertical, and inverted surfaces on most substrates, including bare, coated, and painted concrete; vinyl, ceramic, and linoleum floor tiles; tile grout; aluminum; steel; lead; rubber; Plexiglas®; herculite; wood; and porcelain. Contamination is removed in a peelable film that can be disposed of according to appropriate local, state, and federal regulations. These new gels also can be used to remove particulates, metals, and insoluble organic compounds from surfaces. Demonstrations of the technology have been completed at Oak Ridge National Laboratory in Tennessee, Lawrence Livermore National Laboratory in California, and Alaron Nuclear Services in Wampum, Pennsylvania. Ultimately, decontamination of building and equipment surfaces will reduce disposal costs, as the debris often does not require disposal in a radioactive landfill, which is significantly more expensive than other types of landfills. In some cases, the gel-stripped equipment can be reused rather than disposed of. The decontamination gels also can reduce labor costs and accelerate schedules. Further refinements of the existing DeconGels and development of improved isotope/substrate-specific gels and gels intended for the decontamination of other substances (e.g., beryllium, mercury) will be initiated in FY 2010. http://www.em.doe.gov/pdfs/DOE_EM_Aug%2009_r4.pdf

Department of Homeland Security, Funding Opportunity BAA-10-01, 8 Jan 2010

The Department of Homeland Security (DHS) Science & Technology (S&T) Directorate solicits proposals for Long Range Science and Technology Projects and innovative prototypes that offer potential for advancement and improvement of homeland security missions and operations. S&T is soliciting individuals or teams to conduct work across a spectrum of science and engineering disciplines ranging from basic research to applied technology development to the preparation of integrated prototypes for field investigations. Topical areas of strategic interest include Border and Maritime Security; Chemical and Biological Division analyses and countermeasures (e.g., improved sampling procedures, sample preparation, assays, instruments, characterization, detection); Command, Control, & Interoperability; Explosives Countermeasures, including detection (e.g., standoff detection), mitigation, and response to explosive threats; and other areas described in the full text of the LRBAA This announcement will remain open until December 31, 2010, 11:59 PM, Eastern Standard Time. White papers and full proposals can be submitted at any time during this period. More information under BAA-10-01 at https://baa.st.dhs.gov/

National Science Foundation Funding Opportunity 10-521, 23 Dec 2009

This solicitation will establish a new environmental synthesis center to stimulate research, education, and outreach at the interface of the biological, geological, and social sciences. The center will foster synthetic, collaborative, cross-disciplinary efforts to understand and predict the complex interactions among ecological populations, communities, and ecosystems; the geophysical environment; and human actions and decisions that underlie global environmental change. It will play a pivotal role in forecasting adaptive responses to environmental change and understanding sudden shifts in dynamic systems. The center will also directly involve policy makers, managers, and conservation efforts, and educate an informed citizenry. The center will be international in its scope, addressing the most pressing challenges posed by global environmental change. The center represents a new effort, based on NSF's substantial investments in ongoing synthesis activities and is not intended to extend or duplicate these activities. The Biological Sciences Directorate expects this center to lead the next generation of synthesis activities. A single award is anticipated with estimated total program funding of approximately $30,000,000. The closing date for this opportunity is July 14, 2010. http://www07.grants.gov/search/search.do?&mode=VIEW&flag2006=false&oppId
=50820

McCobb, T.D., D.R. LeBlanc, and A.J. Massey.
Ground Water Monitoring and Remediation, Vol 29 No 2, p 43-55, 2009

Installation of a permeable reactive barrier (PRB) to intercept a phosphate plume where it discharges to a pond provided an opportunity to develop and test methods for monitoring the barrier's performance in the shallow pond-bottom sediments. The barrier is composed of zero-valent iron mixed with the native sediments to a 0.6-m depth over a 1,100-m² area. Permanent suction, diffusion, and seepage samplers were installed to monitor phosphate and other chemical species along vertical transects through the barrier and horizontal transects below and near the top of the barrier. Analysis of pore water sampled at about 3-cm vertical intervals using multilevel diffusion and suction samplers indicated steep decreases in phosphate concentrations in groundwater flowing upward through the barrier. Samples from vertically aligned pairs of horizontal multiport suction samplers also indicated substantial decreases in phosphate concentrations and lateral shifts in the plume's discharge area as a result of varying pond stage. Measurements from Lee-style seepage meters indicated substantially decreased phosphate concentrations in discharging groundwater in the treated area; temporal trends in water flux were related to pond stage. The advantages and limitations of each sampling device are described. Preliminary analysis of the first two years of data indicates that the barrier reduced phosphate flux by as much as 95%. http://www3.interscience.wiley.com/cgi-bin/fulltext/122389136/HTMLSTART

McCobb, T.D., D.R. LeBlanc, L.A. Parsons, and J.G. Blount.
U.S. Geological Survey, Scientific Investigations Map 3078, 1 sheet, Oct 2009

Groundwater contaminated with phosphate because of historical land disposal of treated municipal wastewater at the Massachusetts Military Reservation (MMR) is discharging into nearby Ashumet Pond. Unlike the transport of many contaminants in groundwater beneath the MMR, phosphate transport is greatly retarded because it sorbs strongly to the aquifer sediments. Despite the removal of the wastewater source in 1995, phosphate concentrations in the groundwater will remain elevated for many decades as natural flushing of the aquifer by uncontaminated groundwater results in desorption of this reservoir of sorbed phosphate. The potential adverse effect of continued phosphate loading on the ecology of Ashumet Pond has prompted remedial action. In August 2004, zero-valent iron was mixed into the bottom sediments of Ashumet Pond to reduce phosphate concentrations in groundwater discharging to the pond to limit or reverse the adverse ecological effects of the phosphate. In August 2006, pore-water samples were collected in and near the permeable reactive barrier (PRB) from depths below, within, and at the top of the barrier. This report presents a series of maps showing constituent concentrations and values of physical properties, layered by depth, as a visual assessment of the effects of the PRB on the geochemistry of the pore water along the shoreline of Ashumet Pond. http://pubs.usgs.gov/sim/3078/

U.S. DOE, Office of Environmental Management, ETR-13, July 2009

From 1953 to 1983, ~240,000 pounds of mercury (Hg) were released to East Fork Poplar Creek during the operation of the Y-12 Plant. In 1963, direct systematic releases of mercury stopped; however, mercury continues to be released into the creek from various sources of contamination in the Y-12 complex. Remediation efforts up to 1992 reduced overall Hg loading from 150 g/day in 1983 to 15 g/day in 1992, with a current goal of 5 g/day or less. The metrics for achieving cleanup vary according to the agency of interest; however, national data suggest a clear trend toward the use of fish tissue concentration as the ultimate basis for setting standards. The level of Hg found in the fish in the creek at Y-12 resulted from an intricate series of chemical transformations that began with the initial release of Hg, followed by a series of changes as the Hg was transported through the shallow soil, to the surface and/or shallow groundwater, and then through the reach of the stream drainage. The concentration of Hg in the fish, a potential remedial action endpoint, is better correlated with the concentration of methyl mercury in the stream. Actions that reduce the fraction of Hg converted to methyl mercury within stream water and/or sediment or actions that alter the food chain dynamics therefore are potentially important to addressing the impact of mercury at Oak Ridge. The current groundwater and surface water Hg remediation strategy was reviewed for adequacy in reducing Hg levels in fish and to identify opportunities to achieve cost and technical improvements and/or to address technical uncertainties. The external technical review team recommended the development of a plan (with the participation of affected regulators and stakeholders) that logically integrates the prioritized list of recommendations into a coordinated technical approach. "Quick wins" were recommended for near-term improvements as follows: for Outfall 200, use stannous chloride in the NS Pipe to volatilize Hg, add Hg sequestrants, and use sodium thiosulfate for dechlorination. For the creeks and streams, apply selective physical modification at areas of methylation and add trace Se to reduce methylation and/or uptake. The full 76-page report, "Recommendations to Address Technical Uncertainties in the Mitigation and Remediation of Mercury Contamination at the Y-12 Plant, Oak Ridge, Tennessee," (WSRC-STI-2008-00212, 2008) follows the 1-page ETR-13 fact sheet. http://www.em.doe.gov/PDFs/ORMercuryFinal.pdf

U.S. DOE, Office of Environmental Management, ETR-20, July 2009

Trichloroethene (TCE) is the primary contaminant of concern affecting the X-701B groundwater plume at DOE's Portsmouth facility. The four phases of the remedy are (1) initial source area treatment, (2) expanded source area treatment, (3) evaluation and reporting, and (4) downgradient remediation and confirmation of source area treatment. In Phase 2, catalyzed hydrogen peroxide was injected without meeting the remediation goal of <5 µg/L TCE. The external technical review (ETR) team assessed the ongoing oxidation treatment technology, provided a specific recommendation about continuing oxidant injections, and recommended alternatives to the current remediation strategy for the X-701B plume. The reviewers found that the mass of TCE in the middle and upper Gallia source zone decreased significantly following oxidant injection, while the mass of TCE in the lower Gallia was unchanged overall and increased in some areas. Groundwater concentrations were unchanged or increased after each Phase 2 injection, and all measurements of TCE in the groundwater were 100 to 10,000 times greater than the remediation goal of 5µg/L.The team found that the quantity of oxidant injected during the Phase 1 pilot and the first five Phase 2 injections was significantly less than the amount required to meet the measured soil oxidant demand. Rapid decomposition of the hydrogen peroxide and limited injection volumes likely hindered progress toward remediation goals. The time frame for success is expected to be decades. The ETR team suggested implementing innovative characterization to delineate target source zones the better to focus future source treatments, reduce costs, and minimize collateral damage associated with treatment. An overarching recommendation was to modify the pump-and-treat system to increase effectiveness in terms of contaminant extraction rate and support of other technologies. As none of the available technologies used alone is likely to achieve remedial objectives in a timely manner, the team recommended consideration of a combination of technologies that would work synergistically. Solid oxidants, such as persulfates, could be blended beneath the former source basin (in lieu of a cap), and additional injections of high-strength, long-lived oxidants could be applied in the areas of highest concentration. Thermal technologies are potentially viable if deployment can be performed under a fixed-price, guaranteed-performance contract by a reliable vendor. Soil blending of oxidant, focused TCE characterization, targeted injection of long-lived oxidant solution, and modified pump and treat followed by a passive technique, such as wetland treatment, is an example of a potential treatment technology combination for this site. The full 83-page report, "Independent Review of the X-701B Groundwater Remedy, Portsmouth, Ohio: Technical Evaluation and Recommendations" (SRNL-STI-2008-00424, 2008), follows the 1-page ETR-20 fact sheet. http://www.em.doe.gov/PDFs/SRNL-STI-2008-00424_final.pdf

U.S. DOE, Office of Environmental Management, ETR-8, July 2009

The groundwater underlying the Paducah Gaseous Diffusion Plant (PGDP) is contaminated by chlorinated solvents, principally trichloroethene (TCE), as well as other contaminants. TCE was released as a DNAPL to the subsurface soils and groundwater as a result of operations that began in 1952. The Building C-400 area is coincident with the highest TCE concentrations in the groundwater plumes at PGDP. In 2003, PGDP performed a small-scale pilot test of electrical resistance heating (ERH) and demonstrated that significant amounts of TCE mass could be removed. An external technical review (ETR) team assessed the proposed ERH approach for reducing residual solvent sources in soil and groundwater in the affected area. The team agreed that ERH is a potentially viable remedial technology to meet the remedial action objectives adjacent to C-400, but additional efforts are needed to provide an adequate basis for the planned ERH design in a unique and complex setting, particularly in the highly permeable Regional Gravel Aquifer, where sustaining target temperatures will present a challenge. The ETR team found that the data provide an initial basis for design/operation; however, they recommended that characterization should include expanding the target treatment zones in critical areas and sampling verification during system installation to allow for adjustments, enhanced groundwater monitoring, and future sampling downgradient of the treatment zone. To monitor and improve performance, the TCE in the liquid recovered should be evaluated, the heating target should be increased in the saturated zone beyond the co-boiling point of the TCE, additional technically based metrics should be developed, and broader ERH exit strategy goals should be incorporated into the metrics. Based on the complex hydrogeologic setting and prior evaluations, implementation should incorporate site-specific and verified design models. Additionally, comprehensive (creative and diverse) contingencies should be developed to address the potential for system underperformance and other unforeseen conditions. The full 108-page study, "Review Report: Building C-400 Thermal Treatment 90% Remedial Design Report and Site Investigation, PGDP, Paducah, Kentucky" (WSRC-STI-2007-00427, Rev. 1, 2007), follows the 1-page ETR-8 fact sheet. http://www.em.doe.gov/PDFs/wsrc-sti-2007-00427.pdf

Kaengsepp, P. and L. Mathiasson, Lund Univ., Sweden.
Waste Management & Research, Vol 27 No 2, p 147-158, 2009

A 3-year investigation has confirmed that concentrations of different types of pollutants, most of them at low initial concentrations, can be reduced simultaneously in vertical-flow biofilters containing a mixture of peat and high-carbon ash. The average removal for metals—Mn, Cu, Sn, Cd, Pb, Fe, and Ni—was 73, 72, 66, 60, 55, 55, and 37%, respectively. Monitoring results also showed an average reduction of ammonium-N (45%), N_tot (25%), total organic carbon (30%), dissolved organic carbon (28%), and suspended solids (38%). A good reduction was achieved for phenols (between 75 and 95%), PCBs (between 22 and 99%), and pollutants amenable to gas chromatography/mass spectrometry (between 80 and 100%). The performance of the biofilter system was good in spite of large variations of inlet concentration during the considered period. This paper describes the most important findings concerning the complex composition of the landfill leachate and its on-site, year-round treatment under cold-climate conditions. Additional information on this treatment project can be found in P. Kaengsepp's 2008 dissertation at http://www.lu.se/o.o.i.s?id=12683&postid=1224758

Crawford, S.C., B.A. Smith, and K. O'Shaughnessy (XDD, LLC, Stratham, NH); N.W. Hagelin and R.J. Jacobson (Mactec Engineering and Consulting, Inc., Portland, ME).
Abstracts: The 25th Annual Conference on Contaminated Soils, Sediments, Water and Energy, 19-22 October 2009, University of Massachusetts at Amherst. Association for the Environmental Health of Soils, Amherst, MA, 2009

Residual side-effects of emplacing a large quantity of chemical reagents within an aquifer can include pH impacts, metals mobilization, and accumulation of various breakdown products. These are normal side-effects of in situ chemical oxidation (ISCO) treatment, but it is prudent to consider whether these effects will attenuate, or if they will migrate beyond the treated area. An examination of the long-term residual effects was performed following a full-scale application of alkaline-activated persulfate (AAP) to address 1,1,1-trichloroethane, tetrachloroethene, and 1,4-dioxane contamination. AAP technology involves adjustment of the aquifer pH to alkaline conditions (typically greater than pH 10.5). Reaction of the oxidant (FMC Klozur™ sodium persulfate) at high pH conditions promotes formation of aggressive oxidant radical species (including the sulfate radical SO₄^-). About 15,400 kg of sodium hydroxide was required to adjust pH. A total of 31,100 kg of FMC Klozur™ was injected at field concentrations of 100 to 200 g/L. The remedial goal of 1 mg/L for each of the target compounds was achieved. No significant rebound has been observed over one year after treatment. The residual effects of treatment, including elevated pH (pH > 11), increased metals concentrations (e.g., arsenic up to 15,000 µg/L), and elevated sulfate concentrations (up to 3,200 mg/L), have persisted within the immediate target area. Groundwater plume velocity calculations suggest that if the residual effects were migrating beyond the treated area, these effects should have been observed in downgradient wells. Attenuation mechanisms (i.e., neutralization of pH via soil buffering capacity, re-precipitation of dissolved metals based on Eh-pH characteristics, and dilution mechanisms) have controlled migration of the residual effects. General geochemical principles can be used to anticipate how a proposed ISCO treatment might impact a sensitive aquifer.

Arizona Department of Environmental Quality Fact Sheet, 7 pp, May 2009

The Apache Powder Site is located in Cochise County, Arizona. The site study area covers ~9 square miles and encompasses 945 acres of land owned by Apache Nitrogen Products, Inc., formerly known as the Apache Powder Company. The site was formally listed on the NPL in 1990, and the Record of Decision was signed in 1994. The contaminants of concern are listed as arsenic, fluoride, and nitrate in the perched groundwater; nitrate in the shallow groundwater aquifer; arsenic, antimony, barium, beryllium, chromium, lead, manganese, and nitrate in the inactive pond soils and sediments; and 2,4-DNT, 2,6-DNT, and lead in Wash 3 Area. Additionally, the waste materials vanadium pentoxide and TNT were found in site soils, and perchlorate has been found in the perched and shallow aquifer. The 1994 ROD specified soil excavation, removal, and treatment at a permitted off-site disposal area; removal and treatment of drums containing hazardous materials; capping of contaminated soils left on site; extraction and treatment of the perched groundwater zone by forced evaporation using a brine concentrator; and extraction and biological treatment of water from the shallow aquifer within constructed wetlands, followed by recharge of the treated water. Construction of the 4.5-acre Northern Area Treatment Wetland to process 150 gal/min (80 million gal/yr) of nitrate/nitrogen-contaminated groundwater in the northern portion of the site was completed in September 1997. From 1997 through 2001, the wetland was in a growth phase to develop its aquatic vegetation. During this time, enough biomass was produced to trigger anaerobic denitrification; however, operational problems during the summer of 2002 prevented full-scale startup. The wetland system achieved full-scale startup in late 2004. As of March 2009, the Northern Area wetland has treated over 419 million gallons of groundwater and removed over 507,000 pounds of nitrate/nitrogen. Currently, the wetland is reliably treating nitrate/N-contaminated groundwater to less than 2.0 mg/L (ppm). http://www.azdeq.gov/environ/waste/sps/download/state/apache.pdf

Major, D., Geosyntec Consultants.
Environmental Security Technology Certification Program (ESTCP), Project ER-0116, 92 pp, Apr 2009

The main objectives of Project ER-0116 were to assess the technical feasibility of sequential application of in situ chemical oxidation (ISCO) and in situ bioremediation (ISB) and to identify the optimal timing of the transition from ISCO to ISB. The study approach consisted of a field trial to demonstrate that biostimulation and/or bioaugmentation can stimulate complete dechlorination to a non-toxic product (i.e., providing a mass containment) and whether the mass flux from a source zone increases when biological dehalorespiration activity is enhanced through nutrient addition and bioaugmentation (i.e., providing a secondary source removal technology post-ISCO). The field demonstration was conducted at Launch Complex 34, an unused launch facility at the Kennedy Space Center, Florida, where an extensive trichloroethene (TCE) DNAPL source is present in groundwater in the area adjacent to the Engineering Support Building. The investigators found that electron donor addition (ISB) after ISCO resulted in partial biodegradation of TCE, with complete biodegradation observed after bioaugmentation. At the field scale, ISB did not increase the mass flux of chloroethenes after ISCO. The precipitated manganese dioxide produced by permanganate reduction, which can oxidize some organic compounds, did not abiotically degrade any of the chloroethenes or ethane. Manganese dioxide greatly increased the electron donor demand above that typically required to reduce the dissolved constituents (e.g., oxygen, nitrate, sulfate, and the target chloroethenes) during ISB. Manganese dioxide can be dissolved by the activity of Mn(IV)-reducing bacteria, which appear to utilize hydrogen preferentially and inhibit the activity of dechlorinating microorganisms (i.e., Dehalococcoides, which use hydrogen as their sole electron donor). The limited cost assessment indicated a significant cost and schedule advantage for the sequential treatment strategy over the use of pump and treat or ISCO alone. NASA is currently in the process of developing remedial alternatives as part of the ongoing RCRA response actions at Launch Complex 34. The results of this technology demonstration were incorporated into the process for selecting a final source-zone remediation technology. http://www.estcp.org/Technology/upload/ER-0116-FR.pdf

Hatzinger, P. and J. Diebold, Shaw Environmental, Inc.
Environmental Security Technology Certification Program (ESTCP), Project ER-0224, 536 pp, July 2009

A field demonstration was conducted to evaluate the in situ biological reduction of perchlorate using a horizontal flow treatment well (HFTW) system to mix electron donor into perchlorate-contaminated groundwater. The HFTW technology consists of two dual-screened treatment wells, one pumping contaminated groundwater from a deep aquifer region and injecting it into a shallower zone, and the other pumping contaminated groundwater from the shallower aquifer region and injecting it into the deeper zone. The two wells work in tandem to establish a groundwater recirculation zone in the subsurface. The electron donor is added and mixed with contaminated groundwater at each well, creating an anaerobic, bioactive zone between and downgradient of the HFTWs during system operation. Contaminated water is never brought to the surface, as treatment occurs in the in situ bioactive zones. During ESTCP Project ER-0224, an HFTW system was installed at Aerojet General Corporation's 8,500 acre site in Rancho Cordova, California. A pair of HFTWs were installed ~34 ft apart and screened within a shallow zone in the aquifer from 46 to 61 ft below land surface (bls) (upper screen) and within a deeper zone at 80 to 100 ft bls (lower screen). The screen intervals for the HFTWs (each was screened in both intervals) were determined based on an extensive geological evaluation and groundwater modeling. A group of 19 monitoring wells screened within the shallow and deep zones and placed at various locations upgradient and downgradient of the HFTW pumping wells was used to evaluate overall system performance. Based on laboratory microcosm and column studies, citric acid was utilized as an electron donor throughout the demonstration. This fatty acid was observed to promote biodegradation of perchlorate effectively (as well as co-contaminants nitrate and TCE), while assisting in biofouling control through both acidification of local groundwater and chelation of precipitated metals. Chlorine dioxide also was added periodically to each of the HFTWs during the passive operational phases as a biofouling control agent. The treatment of TCE by the HFTW system was evaluated in Phases II and III, during which the electron donor concentration was increased significantly. A commercial culture containing Dehalococcoides spp. was injected into the HFTWs during Phase II to enhance reductive dechlorination. The operational data from Phase III suggest that an active/passive approach may be the best overall operational strategy for an HFTW system in terms of both contaminant treatment and reduced O&M costs. Pressure increases also occurred in the HFTWs during Phase III, but with the short-term operation and large doses of citric acid, these increases did not affect operation during active phases. Under active/passive operation, the treatment of perchlorate, as well as TCE, was equivalent to or better than that observed during the continuous-pumping phases, while biofouling was more readily controlled. http://www.estcp.org/Technology/upload/ER-0224-FR.pdf

Luthy, R.G., Y.-M. Cho, U. Ghosh, T.S. Bridges, and A.J. Kennedy.
Environmental Security Technology Certification Program (ESTCP), Project ER-0510, 47 pp, May 2009

A field-scale project (ER-0510) was conducted to demonstrate that activated carbon (AC) sorbent mixed with sediment is a cost-effective, non-removal, in situ management strategy for reducing risk and the bioavailability of PCBs in offshore sediments at the Hunters Point Shipyard site in the San Francisco Bay. The project has three primary objectives: demonstrate and compare the effectiveness, in terms of AC application and ease of use, of two available large-scale mixing technologies; demonstrate that AC treatment reduces PCB bioaccumulation in field tests; and show that use of the large-scale mixing technologies does not involve significant sediment resuspension or PCB release. Using two commercial equipment devices, AC was incorporated successfully into the test plots to a nominal 1-ft depth at a dose of 2 to 3%, depending on sampling locations. This was verified by the increases in total organic carbon contents and black carbon contents in AC-amended sediment. In situ 28-day semi-permeable membrane device (SPMD) uptake studies showed 50 to 66% reductions in PCB uptakes in AC-amended test plots, depending on AC dose. In situ bioassays with the bent-nosed clam, Macoma nasuta, also showed the effectiveness of AC treatment. Field-exposed AC retained a strong stabilization capability to reduce aqueous equilibrium PCB concentrations by as much as 95%, depending on AC dose, which indicated the long-term effectiveness of AC in the field at least up to 18 months. Neither PCB resuspension from the test plots nor adverse impacts to indigenous amphipods and benthic community was observed during the entire assessment period. Overall, the AC treatment did not impact macro-invertebrate benthic community composition, richness, or diversity. Cost analysis showed that scaling up the AC treatment method likely would cost 70 to 75% less than dredging and disposal. http://www.estcp.org/Technology/upload/ER-0510-FR.pdf
See also the ESTCP Cost and Performance Report at http://www.estcp.org/Technology/upload/ER-0510-C&P.pdf

Lieberman, M.T. and R.C. Borden, Solutions-IES, Inc.
Environmental Security Technology Certification Program (ESTCP), Project ER-0221, 228 pp, July 2009

ESTCP Project ER-0221 funded a pilot test to monitor and describe the effectiveness of a commercially available emulsified oil substrate (EOS®) for enhancing the biodegradation of chlorinated VOCs in contaminated groundwater and aquifer material in a treatment cell. The project was conducted at a small area within Solid Waste Management Unit 17 at the Charleston Naval Weapons Station, South Carolina. The cell selected for the test contained elevated concentrations of trichloroethene (TCE) in soil (up to 16,000 µg/kg) and groundwater (over 20,000 µg/L). The pilot test design utilized a 20 ft by 20 ft grid to represent cleanup of a "typical" source cell. The saturated zone containing contaminated groundwater was silty clayey sand extending generally between 8 and 18 ft below ground surface. The groundwater gradient was low and tidally influenced, resulting in fluctuating groundwater flow directions. Based on aquifer characterization tests, groundwater flow velocity was estimated to be less than 10 ft/yr. The volume of contaminated aquifer material within the pilot test cell was 4,000 cubic ft. The pilot test results were evaluated for substrate deployment, distribution, contact time, and longevity in the aquifer; changes in aquifer chemistry; and effect on the target contaminants. Phase I included site characterization, baseline sampling, injection of emulsified oil substrate, and performance monitoring for 28 months. Solutions-IES and ESTCP expanded the project to Phase II after the Phase I performance monitoring results indicated that low pH was limiting further biodegradation of the target chlorinated VOCs. Phase II involved a bench-scale treatability study, development and injection of a newly formulated pH-buffered substrate to overcome the pH problem, and an additional 11 months of performance monitoring to measure the effect of the second substrate on enhanced biodegradation. Addition of buffered EOS® in Phase II effectively raised the pH and alkalinity of the aquifer, which allowed the native dehalorespiring populations to re-initiate their metabolism of TCE and DCE and biodegrade TCE throughout the test cell. Over the entire 41-month monitoring period in Phases I and II, the total chlorinated VOC concentration (i.e., sum of PCE, TCE, cis-DCE and VC) decreased from 198 µM to 17 µM, a decline of 91%. Overall, the ESTCP-funded pilot test of the emulsified oil substrate technology was successful in evaluating the performance of this technology. The cost of treatment of the 20 ft by 20 ft pilot test cell was $65,000 for substrate injection and distribution using a network of direct-push wells with re-circulation (Phase I). Based on 4,000 cubic ft of contaminated material, the unit cost to employ this technology was $16/ft³. The cost to perform a direct injection of buffered EOS® into this same pilot test cell (Phase II) was $48,100 ($12/ft³). Based on the data obtained from the initial injection of EOS® in Phase I, the buffered EOS® would also be expected to last at least 3 years without replenishment. http://www.estcp.org/Technology/upload/ER-0221-FR.pdf

O'Reilly, M., P. de Groot, R. Forbes, John Glass, and T. Simpkin.
Abstracts: The 25th Annual Conference on Contaminated Soils, Sediments, Water and Energy, 19-22 October 2009, University of Massachusetts at Amherst. Association for the Environmental Health of Soils, Amherst, MA, 2009

An ISCO pilot test using sodium permanganate is being conducted at MMR to assess the potential of the technology to reduce overall cleanup time and operational costs of groundwater remediation efforts at the site. The pilot test area is located within a large plume of dissolved-phase TCE that has been under active pump and treat since 1999. Due to the thickness of the plume (up to 140 feet) and varying hydrogeologic conditions at the site, three vertically spaced injection well screens at one well cluster were utilized to allow for vertical distribution of the oxidant. The small-diameter injection wells were installed via direct push to depths of up to 200 ft bgs. A closely spaced monitoring network included wells located upgradient, crossgradient, and downgradient of the injection cluster. The monitoring network and sampling program were designed to obtain the information necessary to assess migration and persistence of the oxidant and to evaluate the impacts of oxidant injection on the general geochemistry of the aquifer. The injections covered an area that was ~40 feet wide, 140 feet long, and 50 feet thick. Permanganate was still persistent one year after injection, primarily in the finer-grained sediments near the bottom of the injection zone. Differences in hydraulic conductivity with depth at the site caused a shearing effect in the trajectory of the permanganate as it migrated downgradient. Analytical results and a calibrated groundwater flow and transport model are being used to predict the costs and potential benefits of ISCO on a larger scale in this portion of the plume. For additional information, see the 59-slide presentation by M. O'Reilly posted on the MMR IRP reports and presentations page at http://www.mmr.org/Community/teams/pct2/meetings.htm
Scroll down to October 14, 2009, to locate "Chemical Spill-10 In Situ Chemical Oxidation (ISCO) Pilot Test."

Liles, D.S., Arcadis.
Environmental Security Technology Certification Program (ESTCP), Project ER-0017, 8 pp, Feb 2009

ARCADIS conducted a laboratory research project under ESTCP Project ER-0017 that evaluated the reductive dechlorination of trichloroethene (TCE) by multiple types of nanoscale zero-valent iron (nZVI) particles obtained from multiple manufacturers. The manufacturing methods used to make the nZVI particles utilized during the study produce particles that fall into two structural categories defined during this research as including particles with amorphous atomic structures and those with crystalline atomic structures. Structural differences in iron particles can lead to profoundly different properties during the utilization of the nZVI for reductive dechlorination of TCE. Different phases of the laboratory program focused on the reactivity, longevity, injectability, and potential for treatment of DNAPL for multiple manufactured types of nZVI with both amorphous and crystalline structures. Over the multi-year laboratory research program, several of the multiple venders of nZVI contributing materials were engaged in product development/improvement efforts, leading to nZVI with enhanced performance characteristics. Due to the relatively high cost of nZVI as a consumable remediation reagent, the laboratory program was aimed at investigating the factors that combine to influence return on investment, such as rate of reactivity, longevity under aquifer conditions, and potential for effective treatment of DNAPL. The investigators learned that initial rates of reaction of different batches of iron provided by the same manufacture under the same brand name can differ dramatically, which likely reflects the continuing evolution of the manufacturing technology. The investigators recommend that each individual batch of iron undergo kinetics testing as a quality control step before application in the field. All of the tested nanoscale iron products generated visible evolution of a gas, believed to be hydrogen, during acid washing, and several nZVI products did so before acid washing, which indicates the importance of taking safety precautions during storage, shipment, and application. Exposure to water causes a decline in reactivity, possibly due to water dissociation, which means that nZVI products manufactured and/or shipped in aqueous solutions are at a disadvantage with regard to reactive life compared to particles that are manufactured and shipped as nonaqueous dispersions. Both types of particles likely can be used for the treatment of source zones or high-concentration zones adjacent to source areas. The amorphous particles likely are best used in source areas only under conditions where potential for hydrogen transport out of the treatment zone is low or where contemporaneous biological treatment via stimulation with carbon substrates is taking place. The crystalline particles are more suitable for high-flow conditions or completely abiotic treatment. Contrary to expectation, in almost all cases the TCE removal performance of nZVI particles was better in the non-palladized form compared to palladized particles. The data used to make these conclusions comes from detailed reports generated during this project and supplemented by the available literature. http://www.estcp.org/Technology/upload/ER-0017-LL.pdf

Hansen, K.A., M. Fitzpatrick, P.R. Herring, and M. VanHaverbeke.
Report No. CG-D-08-09, 74 pp, July 2009

Current methods for locating and recovering submerged oil spills are inadequate. Detection methods often are improvised on-scene, and recovery techniques are labor intensive and not always successful. The U.S. Coast Guard Research and Development Center has embarked on a multi-year project to develop a complete approach for dealing with spills of submerged oils. This report describes an assessment of detection techniques using sonar, laser fluorometry, real-time mass spectrometry, and in situ fluorometry to locate oil sitting on the sea floor. Evaluation of four proof-of-concept devices was conducted at OHMSETT, the National Oil Spill Response Research & Renewable Energy Test Facility in Leonardo, New Jersey, between November 2007 and February 2008. Further testing of two of these prototype devices, plus three additional detection systems, was conducted at OHMSETT in January 2009. This report contains the results of the tests and provides recommendations in Appendix E for federal on-scene coordinators when responding to spills of heavy oil. http://www.crrc.unh.edu/workshops/liquid_asphalt/RDC_submergedoildetecti
on_Report_june09.pdf

Lieberman, S.H., Space and Naval Warfare Systems Command.
Environmental Security Technology Certification Program (ESTCP), Project ER-0109, 170 pp, 2007 [posted Dec 2009]

Project ER-0109 evaluated two technologies: the halogen-specific detector (XSD) and the high resolution fluorescence (HRF) sensing system. The XSD can be operated downhole behind a membrane interface probe (MIP) that samples the soil formation for VOCs. Moving the detector downhole and measuring while the direct-push probe is continuously advanced can increase the spatial resolution of DNAPL detection by an order of magnitude (from feet to inches). Even higher spatial resolution (tenths of inches) can be obtained with a complementary HRF sensing system that can be applied whenever the DNAPL is fluorescent owing to dissolved petroleum products or humic substances. The ability of the characterization techniques to find DNAPL was verified via GeoVIS in situ video imaging. The evaluations were conducted at Naval Air Station North Island, California, and at Marine Corps Base Camp Lejeune, North Carolina. At North Island, the XSD clearly showed several areas that were heavily impacted by halogenated compounds, indicating heavy dissolved-phase halogenated compounds in areas not determined in extensive previous studies. At Camp Lejeune, the XSD clearly delineated zones of chlorinated VOC contamination, and water sampling confirmed the relative accuracy of the XSD concentration vs. depth profiles. Maintaining an acceptable MIP temperature was difficult. While this negatively affected mass transport owing to the presence of a compound (PCA) that has a high boiling point (146°C) and relatively low vapor pressure (6.36 torr), successful profiling was still accomplished. XSD signal levels were not saturated at Camp Lejeune, even in areas later found to have DNAPL. With the laser-induced fluorescence (LIF) at Camp Lejeune, false positives were encountered; elevated LIF responses did not always prove to be a positive indicator for DNAPL. It should be noted that the XSD-MIP is a screening tool and is incapable of achieving analytical performance in real time on the inherently heterogeneous matrix of the subsurface. Although the logs are not analytically accurate in a quantitative sense, their value lies in their ability to paint an instant picture of the subsurface HVOC distribution. The true value of tools such as the XSD-MIP is their ability to be used in real time to move adaptively about the site, follow gradients toward locations with higher signal levels both laterally and horizontally, and finally pinpoint the true hotspots and likely DNAPL source term areas. http://www.estcp.org/Technology/upload/ER-0109-FR_PMa_Final.pdf

Brauner, J.S., D.C. Downey, and R. Miller, Parsons Infrastructure and Technology Group.
Strategic Environmental Research and Development Program (SERDP), Project ER-1348, 462 pp, Oct 2008

This report presents a strategy and framework for quantitatively assessing the sustainability of monitored natural attenuation (MNA)-based remedies for groundwater at chlorinated solvent-impacted sites. It also provides case study reviews using existing long-term monitoring (LTM) data sets from multiple U.S. Air Force sites where chlorinated solvents exceed closure criteria, and summarizes observations and recommendations developed when working through the case study examples. While the original intent of the current study was to apply the methods described in this report solely to sites where MNA was the primary remedy, it was recognized during the implementation of the plume stability evaluation process that these methods can also be used for the assessment of active remedies. A case study example that applies the suggested plume stability analysis methods to data from a pump-and-treat remedy is provided to illustrate the flexibility of the proposed approach for evaluating active remedy performance. Application of these methods to other sites where active remedies (e.g., chemical oxidation, chemical reduction, enhanced bioremediation) have been implemented is a recommended next step for evaluating the robustness of the methods described in this report. http://www.serdp.org/Research/upload/ER-1348-FR.pdf

U.S. EPA, National Exposure Research Laboratory, Las Vegas, NV.
EPA 600-R-09-073, 326 pp, Aug 2009

A study was undertaken to assess the vertical and horizontal distribution of VOCs in the subsurface from groundwater to the surface/subslab environment and to develop a database of paired macro-purge and micro-purge soil gas sample measurements. In addition, sampling was conducted to evaluate the performance of a variety of soil gas probe construction materials (tubing types) and to test passive diffusion samplers (PDSs). The field study was conducted at Installation Restoration Program Site 14 on Naval Air Station Lemoore, California, where chlorinated VOCs (mainly TCE with some DCE, 1,2-DCE, DCA, 1,2-DCA, and PCE) have been found in soil, soil gas, and groundwater. The results of the investigation into the distribution of soil gas VOCs near a slab indicate that, as expected, VOC concentrations in soil gas decrease with increasing vertical separation from the groundwater source and with increasing horizontal distance away from the edge of the slab; however, the decline in soil gas VOC concentrations moving horizontally away from the edge of the slab was more rapid than expected. Limited groundwater data show a corresponding large decrease in VOC concentrations moving away from the slab, which indicates that the presence of the slab can have a significant and abrupt impact on VOC concentrations in soil gas and the uppermost groundwater, with important implications for sample location selection in vapor intrusion studies. The comparison of TCE soil gas concentrations from the macro-purge versus micro-purge methods showed a maximum difference of a factor of 4 with an average difference of 2.2. The statistical analyses indicate a correlation between the results obtained from the two sampling methodologies; however, the range of relative percent differences for the macro-purge samples at 50 samples was 260%, which suggests that some as-yet undetermined issues with this sampling method are limiting its reproducibility. Evaluation of different tubing types indicates that stainless steel, Nylaflow, PEEK, and Teflon tubing are all suitable materials for probe construction, but polyethylene tubing should be avoided, and copper tubing is not suitable for soil gas probe construction. Soil gas equivalent TCE concentration results for the PDSs generally were higher than the corresponding active soil gas sample concentrations. Additional data are needed to assess the performance of the PDS more completely. http://www.epa.gov/nerlesd1/cmb/pdf/EPA600-R-09-073.pdf

Vroblesky, D.A., M.D. Petkewich, J.E. Landmeyer, and M.A. Lowery.
U.S. Geological Survey Scientific Investigations Report 2009-5161, 80 pp, 2009

Groundwater contamination by tetrachloroethene (PCE) and its dechlorination products is present in two partially intermingled plumes in the surficial aquifer near a former dry-cleaning facility at Site 45, Marine Corps Recruit Depot, Parris Island, South Carolina. The northern plume originates from the vicinity of former aboveground storage tanks. Free-phase PCE from activities in this area entered the groundwater and the storm sewer. The southern plume originates at a nearby new dry-cleaning facility but probably was the result of contamination released to the aquifer from a leaking sanitary sewer line from the former dry-cleaning facility. Dissolved groundwater contamination discharges primarily to leaking storm sewers below the water table. Extensive biodegradation of the contamination takes place in the surficial aquifer; however, the biodegradation is insufficient to reduce trichloroethene (TCE) to less than mg/L concentrations prior to discharging into the storm sewers. The groundwater VOCs entering the storm sewers are diluted by tidal flushing upon entry and are subject to volatilization as they pass through the storm sewer to a discharge point in a tributary to Ballast Creek. TCE concentrations of 2 to 6 µg/L were present in storm-sewer water near the discharge point (sampled at manhole STS26). On three out of four sampling events at manhole STS14, the storm-sewer water contained no vinyl chloride. During a time of relatively high groundwater levels, however, 20 µg/L of vinyl chloride was present in STS14 storm-sewer water. Because groundwater leaks into that storm sewer and because the storm sewer upgradient from manhole STS14 is adjacent to part of the aquifer where 2,290 µg/L of vinyl chloride has been detected, there is a potential for substantially increased concentrations of vinyl chloride to discharge at the storm-sewer outfall under conditions of high groundwater levels and low tidal flushing. In addition, the observation that free-phase PCE might have entered the storm sewer during the 1994 discharge means that DNAPL PCE could have leaked from various parts of the storm sewer or discharged to surface water at the storm-sewer outfall. The difference between the chemistry in the northern and southern plumes may be partly because the northern plume has been the focus of a variety of treatment pilot studies: air sparging in 1996, groundwater pump and treat from 1998 to 2000, and emulsified zero-valent iron injection in late 2006. http://pubs.usgs.gov/sir/2009/5161/

Environmental Management Engineering and Technology Highlights, p 3, Sep 2009

Dr. Hope Lee, Idaho National Laboratory, has used innovative molecular and geochemical methods, such as the enzyme activity probe (EAP), to document that naturally occurring microorganisms are degrading chlorinated solvents like trichloroethene (TCE) in groundwater plumes. If natural attenuation is included as part of the remedy for contaminated groundwater, use of these innovative techniques could generate significant savings during cleanup and site closure. As part of Savannah River National Laboratory's Monitored Natural Attenuation Project, Dr. Lee led the TCE Fate and Transport Team's investigation in the Regional Gravel Aquifer at DOE's Paducah Site in Kentucky. Researchers found that 90% of the groundwater samples from 10 wells within the Northwest Plume at Paducah contained microorganisms that can degrade TCE. To understand the overall impact of the microbial processes on plume cleanup, a kinetic study is underway at the Paducah Northwest Plume to determine how rapidly the microorganisms are degrading TCE. To further her research, Dr. Lee has received funding from DoD's Environmental Security Technology Certification Program (ESTCP) and DOE's Office of Environmental Management (EM) to study cometabolic degradation at diverse sites with large groundwater contaminant plumes in varying climatic and geological conditions across the United States. DOE facilities with groundwater plumes suitable for Lee's study include Savannah River, Paducah, Brookhaven, Lawrence Livermore, Hanford, and Idaho. U.S. EPA's natural attenuation guidance requires demonstration and quantification of multiple lines of evidence to demonstrate degradation processes that enable prediction of whether the site will meet cleanup goals within a reasonable timeframe. The EAP method, when used in combination with deoxyribonucleic acid (DNA) confirmation, provides a cost-effective toolkit to identify and quantify the microorganisms that are actively degrading contaminants. http://www.em.doe.gov/pdfs/DOE_EM_Aug%2009_r4.pdf

McLoughlin, E., A.H. Rhodes, S.M. Owen, and K.T. Semple.
Environmental Pollution, Vol 157 No 1, p 86-94, 2009

The effects of monoterpenes on the degradation of 2,4-dichlorophenol (DCP) labeled with C-14 were investigated in soils collected from areas surrounding monoterpene and non-monoterpene-emitting vegetation. Indigenous microorganisms degraded 2,4-DCP to radiolabeled carbon dioxide after 1 day of contact time. Degradation was enhanced by prior exposure of the soils to 2,4-DCP for 32 days, which increased extents of mineralization up to 60%. Monoterpene amendments further enhanced 2,4-DCP degradation, but only following pre-exposure to both 2,4-DCP and monoterpene, with total 2,4-DCP mineralization extents of up to 71%. Degradation was greatest at the higher monoterpene concentrations (≥1 µg/kg). Total mineralization extents were similar between concentrations but higher than the control and the 0.1 µg/kg amendment, indicating that increases in monoterpene concentration has a diminishing enhancing effect. The authors suggest that monoterpenes can stimulate the biodegradation of 2,4-DCP by indigenous soil microorganisms and that monoterpene amendment in soils is an effective strategy for removing organic contaminants. http://nora.nerc.ac.uk/5337/1/McLoughlinPPN005337.pdf

Gacura, Matthew D., Master's thesis, Youngstown State University, 57 pp, Aug 2009

A study was conducted to optimize bioremediation of Mahoning River sediment historically contaminated with polycyclic aromatic hydrocarbons (PAHs) using white rot fungi. Pleurotus ostreatus grown on grain (10% v/v) was added to contaminated sediment amended with sawdust (80% v/v) with and without fungal-specific nutritional nitrogen (to enhance fungal growth) and with cyclodextrin (to increase PAH availability). Sediment mixtures were incubated in the dark at 25°C for 6 weeks. Sawdust made the sediment more porous, allowed better colonization by fungi, and did not greatly increase volume. Fungal biomass, determined using fluorescent microscopy, indicated initial fungal colonization followed by inhibition of fungal growth, likely by toxic metals or high moisture content in the sediment. Growth of unidentified fungi was observed, especially in treatments amended with nitrogen. Within the first two weeks, total PAH concentrations (~100 ppm) analyzed using a gas chromatograph mass spectrometer (GCMS) decreased significantly 50 to 60% in all treatments, including sediment-only controls. Aerobic degradation by native bacteria and volatilization likely were responsible for most of the observed decreases in PAH concentrations. High heterogeneity of PAHs in the sediment led to high variance between replicates. A slight decrease in 5-ring PAHs associated with sediment inoculated with P. ostreatus was observed, as well as a slight decrease in total PAHs associated with sediment amended with sawdust and cyclodextrin (with or without P. ostreatus). Increased nitrogen did not enhance PAH degradation. After two weeks, sediment inoculated with P. ostreatus showed better fungal growth and colonization, but PAH data were not yet available. The available data indicate considerable potential for bioremediation of PAH-contaminated sediment conditions by stimulation of indigenous bacteria under aerobic conditions followed by the addition of white rot fungi, although further testing and optimization is required. http://etd.ohiolink.edu/view.cgi?acc_num=ysu1254341459

Noell, A.L., Terracon, Inc., Dallas, TX.
Practice Periodical of Hazardous, Toxic, and Radioactive Waste Management, Vol 13 No 1, p 35-44, 2009

A sequential anaerobic/aerobic bioremediation pilot test was performed to assess its viability for chlorinated ethenes and to determine scaling parameters for remedial design. Transect data were evaluated to determine the first-order degradation rate of trichloroethene (TCE). Because the Damkohler numbers were greater than unity, a single-well regression approach was used to estimate the sequential first-order degradation rates. The biostimulated degradation kinetics were influenced by competing electron acceptors and total organic carbon. First-order degradation kinetics were appropriate after the biomass population was stimulated and critical redox conditions were established. First-order degradation rate coefficients (λ) were calculated for the anaerobic and aerobic degradation of TCE, cis-1,2-dichloroethene (cDCE), and vinyl chloride (VC) using regression analyses from predominant daughter products. In anaerobic groundwater, λTCE=0.084/days, λcDCE=0.037/days, and λVC=0.046/days adjacent to injection and λTCE=0.037/days and λcDCE=0.020/days further downgradient. In aerobic groundwater, λcDCE=0.036/days and λVC=0.11/days. The groundwater residence times required to satisfy regulatory limits were estimated for different conceptual remediation scenarios.

Cozzarelli, I.M., B.A. Bekins, R.P. Eganhouse, E. Warren, and H.I. Essaid, USGS.
Journal of Contaminant Hydrology, Vol 111 Nos 1-4, p 48-64, 15 Jan 2010

Benzene and alkylbenzene biodegradation rates and patterns were measured using an in situ microcosm in a crude-oil contaminated aquifer near Bemidji, Minnesota. Benzene-D6; toluene; ethylbenzene; o-, m- and p-xylenes; and four pairs of C3- and C4-benzenes were added to an in situ microcosm and studied over a 3-year period. The microcosm allowed for a mass-balance approach and quantification of hydrocarbon biodegradation rates within a well-defined iron-reducing zone of the anoxic plume. Among the BTEX compounds, the apparent order of persistence is ethylbenzene > benzene > m,p-xylenes > o-xylene ≥ toluene. Threshold concentrations were observed for several compounds in the in situ microcosm, below which degradation was not observed, even after hundreds of days. In addition, long lag times were observed before the onset of degradation of benzene or ethylbenzene. The isomer-specific degradation patterns were compared to observations from a multi-year study conducted using data collected from monitoring wells along a flowpath in the contaminant plume. The data were fit with both first-order and Michaelis-Menten models. First-order kinetics provided a good fit for hydrocarbons with starting concentrations below 1 mg/L and Michaelis-Menten kinetics were a better fit when starting concentrations were above 1 mg/L, as was the case for benzene. The biodegradation rate data from this study were also compared to rates from other investigations reported in the literature.

Tollbaek Johanna, Ph.D. dissertation, Stockholm Univ., Sweden, ISBN: 978-91-7155-843-5, 81 pp, 2009

The work presented in this thesis concerns the development and evaluation of new methods of sampling and analysis of organic pollutants in the indoor and outdoor environment. Paper I reports the development of a new method for the determination of the brominated flame retardant tetrabromobisphenol A (TBBPA) in air using sampling with glass fiber filter and polyurethane foam, ultrasonic solvent extraction, and liquid chromatography coupled to electrospray ionization mass spectrometry (MS). The MS fragmentation mechanism of TBBPA was thoroughly investigated, and different acquisition modes were evaluated to achieve the most sensitive and selective detection. In Papers II and III, the potential use of Empore SPE membranes was evaluated for air sampling of volatile, semi-volatile, and particle-associated organic compounds. Breakthrough studies conducted for 24 hours at air flows of 10 to 20 L/min showed that the SPE membranes efficiently retain volatile and semi-volatile organophosphate esters and particles >10 nm. Effort was invested in the development of fast, low-cost, environmentally friendly methods for sample cleanup and analysis. In Paper II, the sample preparation technique was dynamic solvent extraction with methanol coupled to LC-ESI/MS. The total run time per sample, including both extraction and separation, was less than 34 minutes, consuming only 1.6 mL methanol. Paper III details an investigation of the efficiency of selective extraction of polycyclic aromatic hydrocarbons from particulate matter sampled with Empore SPE membranes using dynamic subcritical water extraction. The approach achieved acceptable recoveries of the investigated compounds from reference material (SRM 1649a). Paper IV describes an evaluation of the application of dynamic solid-phase micro-extraction air sampling using gas chromatography/positive ion chemical ionization and tandem-MS detection for the determination of organophosphate esters in the work environment. http://su.diva-portal.org/smash/record.jsf?pid=diva2:211116

Barth, E.F., T. Reponen, and P. Succop.
Journal of the Air & Waste Management Association, Vol 59 No 5, p 540-552, 2009

Exothermic volatilization of VOCs from lime-treated sediment is well known, but potential aerosolization of bioaerosol components has not been evaluated. An experimental protocol and a physical model of a contaminated sediment treatment and airborne transport process were developed to identify specific bioaerosol components (bacteria, fungi, cell structural components, and particles) that can be aerosolized and transported. Key reaction variables (amount of lime addition, rate of lime addition, mixing energy supplied) that might affect the aerosolization of bioaerosol components were evaluated. Lime treatment of a sediment contaminated with heavy metals, petroleum-based organics, and microorganisms increased the sediment pH and solids content. Lime treatment reduced the number of water-extractable bacteria and fungi in the sediment from approximately 106 colony-forming units (CFU)/mL to less than the detection limit of 103 CFU/mL. This reduction was seen immediately for bacteria and within 21 days for fungi. Lime treatment immediately reduced the amount of endotoxin in the sediment, but the effects of lime treatment on beta-D-glucan could not be determined. The temperature of the treated sediment had a linear relationship to the amount of lime added within the range of 0 to 25%. Bacteria were aerosolized during the treatment trials, but there was no culturable evidence of aerosolization of fungi, likely because either their particular growth stage or relatively larger particle size reduced their aerosolization potential and their collection into the impingers. Nonbiological particles, endotoxin, and beta-D-glucan were not detected in air samples during the treatment trials. The amount of lime added to the reaction beaker and the relative amount of mixing energy supplied to the reaction significantly affected the aerosolization ratio of bacteria (amount of aerosolized bacteria divided by amount of bacteria in untreated sediment) from the reaction beaker. The rate of lime addition did not affect the aerosolization ratio of bacteria significantly. The aerosolization results suggest that exposure to bacteria is possible with sediment treatment activities, but the hazard level could not be determined because speciation of the aerosolized bacteria for pathogen identification was not performed, and health and safety standards and criteria for bioaerosol components have not been developed. Additional information on this research is available in E.F. Barth's dissertation at http://etd.ohiolink.edu/view.cgi?acc_num=ucin1155653589

Alvarenga, P., A.P. Goncalves, R.M. Fernandes, A. de Varennes, E. Duarte, A.C. Cunha-Queda, and G. Vallini.
Waste Management & Research, Vol 27 No 2, p 101-111, 2009

Mine soil from a pyrite mine (SW Portugal in the Iberian Pyrite Belt) with high levels of Cu, Pb, and Zn was amended with three different types of organic residues—sewage sludge from a municipal wastewater treatment plant (SS), compost from the organic fraction of unsorted municipal solid waste (MSWC), and garden waste compost (GWC)—applied at 100 and 200 Mg/ha. The soil and mixtures of soil and amendments were adjusted to 70% of the maximum water-holding capacity determined for each type of sample and incubated in a controlled-temperature room at 20 ± 1°C. Sub-samples were taken prior to wetting (time zero), and after 7, 14, 21, and 28 days of incubation. The samples were analyzed for pH; electrical conductivity; organic matter content; effectively bioavailable Cu, Zn, and Pb (extracted with 0.01 mol/L calcium chloride); and potentially bioavailable metals (extracted with 0.5 mol/L ammonium acetate, 0.5 mol/L acetic acid and 0.01 mol/L EDTA, pH 4.7). In general, organic residues corrected soil acidity and increased the total organic matter content of the soil. The SS and the MSWC amendments were roughly equivalent in their ability to correct soil acidity, whereas the GWC had the smallest liming capacity; only with 200 Mg/ha GWC did the soil pH reach acceptable values. As expected, all the tested organic residues were effective at both application rates in reducing the effectively bioavailable metals in the soil. Zn bioavailability was most affected by the addition of organic residues, while Pb bioavailability was small even in the unamended soil and was the least affected by the treatments. Potentially bioavailable metals increased with SS and MSWC application, but a reverse effect followed amendment with GWC.

Jonsson, Sofia, Ph.D. dissertation, Umea University, Sweden, ISBN: 978-91-7264-763-3, 2009

Organic contaminants at old industrial sites become increasingly strongly sequestered as they persist in the soil matrix for a long period of time. This aging process leads to decreasing availability of the contaminants, which also affects remediation efficiency. The work underlying this thesis investigated the influence of soil type and properties of contaminants—polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCDFs)—on the efficiency of various physical and chemical soil remediation methods. The results show that as the size of soil particles decreases, the contaminants become more strongly sorbed to the soil's matrix, probably due to the accompanying increases in specific surface area. The efficiency of the removal of organic pollutants was tested using separate solvent washing and chemical oxidation processes. The sorption strength is affected by the hydrophobicity of the contaminants, but the chemical reactivity of some of the PAHs was found to be of greater importance for degradation efficiency. The effect of the organic content of soil was found to be particularly pronounced for the oxidation of low molecular weight PAHs, although the larger PAHs were strongly adsorbed even at low levels of organic matter. For the larger PAHs, the degradation efficiency was correlated positively to the amount of degraded organic matter, likely due to oxidation of the organic matter to smaller and less hydrophobic forms. The amount of organic matter in the soil had little effect on the removal efficiency obtained by the solvent washing process, but it strongly influenced the performance of a subsequent, GAC-based post-treatment of the washing liquid. The results in this thesis show that remediation of contaminated soils is a complex process, the efficiency of which will be affected by the soil matrix as well as the properties of the contaminants present at the site. By acquiring a thorough knowledge of the parameters affecting the treatability of a soil, it is possible to select appropriate remediation methods and optimize them in terms of both remediation efficiency and costs for site- and contaminant-specific applications. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-21040

Stephenson, G., Stantec Consulting Ltd., Surrey, BC, Canada.
Proceedings of the PTAC Soil and Groundwater Forum and Poster Session, Calgary, Alberta, 13 Mar 2009. Web site of Petroleum Technology Alliance Canada, Calgary, AB, 23 slides, 2009

Risk estimates and exposure scenarios hardly ever take into consideration site-specific bioavailability of contaminants. Risk assessors frequently adopt the assumption that a contaminant in soils is 100% bioavailable, resulting in an overestimation of the risks associated with contamination. Remedial targets or benchmarks derived in light of this assumption are needlessly low and might be technically unattainable or prohibitive in terms of cost. This presentation discusses research aimed at developing a tool kit to measure or determine site-specific bioavailability of petroleum hydrocarbons (PHCs) in soils to ecological receptors. Useful tools include biological measures, such as toxicity tests, contaminant residues in tissues, and bioaccumulation tests; and chemical measures, such as bioaccessibility tests and other biomimetic devices (e.g., SPMDs), biotic ligand modeling, and chemical extractions. Preliminary investigation results are provided. The presentation also touches upon single-species toxicity tests, preliminary comparisons, bioaccumulation, and toxicity to earthworms. Study results indicate that total soil and water-extractable concentrations did not correlate well with toxicity. This presentation and 17 others have been posted at http://www.ptac.org/env/envf0902p.html

Fuller, M.E. and C.E. Schaefer, Shaw Environmental, Inc.
Environmental Security Technology Certification Program (ESTCP), Project ER-0434, 225 pp, Jan 2010

A combination of Sphagnum peat moss and crude soybean oil (PMSO) was examined as an in-place treatment option for reducing the transport of dissolved explosives from munition residues on active training ranges. An evaluation was performed using outdoor ex situ soil plots at the Massachusetts Military Reservation. The study was directed at measuring the reduction in the flux of explosive compounds (i.e., RDX, HMX, TNT) from freshly deposited Composition B detonation residues into the underlying soil. Over a 1-year period, the PMSO treatment layer reduced the average flux of RDX at ~30 centimeters below the soil surface by between 5- and 500-fold compared to control plots. Treatment effectiveness was dependent on the specific proportions of peat moss and crude soybean oil in the PMSO. Detections of TNT, HMX, and the RDX degradation products MNX, DNX, and TNX in pore water were minimal and sporadic at all sample depths. A parallel demonstration examining the compatibility of the PMSO technology with range activities was performed at a hand grenade training range at Fort Jackson, South Carolina. The PMSO material was not adversely affected by the hand grenades, which redistributed the material horizontally and vertically; however, large detonations of C4 explosives and hot, dry, and windy conditions resulted in some smoldering and generation of nuisance dust from the PMSO. These results indicate significant potential for this inexpensive and readily available PMSO material to reduce the migration of explosives residues into groundwater. This technology would be expected to be as effective at reducing explosive compound fluxes if it was emplaced as a barrier below a layer of soil to prevent generation of nuisance dust, and it would be most applicable at grenade ranges, mortar firing points, OB/OD areas, and EOD training facilities that are under active management. http://www.estcp.org/Technology/upload/ER-0434-FR%20Grenade%20Range.pdf

Environmental Security Technology Certification Program (ESTCP), Project ER-0222, 39 pp, Aug 2009

Ammunition manufacture is the second largest consumer of lead (Pb) in the United States after Pb acid batteries and represents approximately 80,000 metric tons per year. About 3,000 small arms ranges (SARs) exist, the berms of which act as reservoirs for spent ammunition. DoD has a vested interest in monitoring the status of these sites. Risk management of Pb at SARs depends on the site end use, whether the range is open or closed, and whether the risk drivers are human or ecologic. U.S. EPA's risk assessment guidelines (RAGs) allow for applications of site-specific bioavailability for Pb where this bioavailability differs from the assumed default of 60%. Assessing the site-specific bioavailability of Pb historically has been carried out using the in vivo juvenile swine model, but significant reduction in cost and time could be achieved by using less expensive, less technical, and less time-consuming in vitro models. ESTCP Project ER-0222 compared bioavailability of Pb from SAR soils from eight different sites, using both an established in vivo and in vitro method. The in vivo method was based on the measured absorption of soil Pb (compared to Pb acetate) by swine dosed daily for 14 days, using the ratio of the blood dose-response slopes for each compound. For the in vitro method, Pb was extracted from an aliquot of soil for 1 hour at 37°C using glycine/HCl buffer at pH 1.5. The extractable Pb was expressed as a percentage of the total Pb in the sample. The initial aims of the study were to compare a projected range of bioavailability in a range of soils, creating a linear comparison between both methods, but all eight soils carefully selected for testing were determined to have high bioavailability, regardless of source, pH, cation exchange capacity, or organic matter. The mean in vivo and in vitro bioavailability results were 107 ± 18% and 95 ± 6%, respectively, indicating a high degree of concordance despite the widely different methods. The in vitro method is a good predictor of the in vivo results, further strengthening the existing data for correlation between these two methods. Speciation analysis showed that Pb in the eight soils existed predominantly as Pb carbonate or oxide, compounds with known high bioavailability. An additional 20 SAR soils from across the United States, screened using only the in vitro method, also had high bioavailability (91 ± 11%), leading to the overall conclusion that Pb at the majority of SARs has high bioavailability. http://www.estcp.org/Technology/upload/ER-0222-C&P.pdf

Baker, R.S. (TerraTherm, Inc.); U. Hiester (Univ. of Stuttgart).
Strategic Environmental Research and Development Program (SERDP), Project ER-1423, 250 pp, May 2009

Thermal conductive heating (TCH) is an in situ thermal remediation technology that takes advantage of the invariance of thermal conductivity across a wide range of soil types to effect treatment of DNAPL above and below the water table, particularly in lower-permeability and heterogeneous formations. TCH can complement steam enhanced extraction (SEE), which generally is more applicable to higher-permeability formations below the water table. Project ER-1423 had the following objectives: (1) determine the relative significance of the various contaminant removal mechanisms below the water table (e.g., steam generation, steam stripping, volatilization); (2) assess the DNAPL source removal efficiency and accompanying change in water saturation at various treatment temperatures/durations through boiling; and (3) evaluate the potential for DNAPL mobilization, either through volatilization and recondensation and/or pool mobilization outside the target treatment zone during heating. The investigators identified dominating processes, those of lesser importance, and even small-scale effects. The experimental results indicate that advanced numerical simulations would be very helpful to predict steam front propagation, temperature distribution, and DNAPL recovery. In some respects, predictions gleaned from numerical simulations proved of value to process understanding; in other respects they differed from the experimental results. http://www.serdp.org/Research/upload/ER-1423-FR.pdf

Reilly, Michael.
Discovery News at msnbc.com, 27 Apr 2009

On the banks of the Saigon River in Vietnam, researchers have completed tests on a new way to combat water pollution that could save millions of lives in coastal cities in the developing world. In factories on the outskirts of Ho Chi Minh City, Dr. Stephan Koehler of the Graz University of Technology in Austria and a team of researchers have cleansed water contaminated with toxic metals like cadmium, zinc, lead, and iron. The team did it using one of the cheapest, most abundant materials around: seashells. Dr. Koehler's team has found that pouring metal and acid-laden water over a bed of crushed clam or mussel shells provides an easy fix. The shells are made of aragonite, a form of calcium carbonate that readily swaps its calcium atoms in favor of heavy metals, locking them into a solid form. The shells are alkaline—a pH of 8.3 when dissolved that can be maintained by adding more shells. The team's technique stems from work in 2003 by Dr. Manuel Prieto of Oviedo University in Spain, who first showed that shells effectively remove cadmium from water. Dr. Koehler's team has now expanded upon that work to encompass other heavy metals, including lead. Their work in Vietnam also shows that the technique works on wastewater produced from real-world factory processes.

Barsotti, D., G. Bondy, M. Miller, and L. Stirban, MACTEC Engineering and Consulting, Inc.
The Michigan Environmental Professional, p 5-8, Spring 2009

An investigation was conducted to develop site-specific sediment and surface water preliminary remediation goals (PRGs) for the Ironton Tar Plant site (Ironton, Ohio) consistent with regulatory guidance. To achieve this objective, both upstream contributions and bioavailability were evaluated for the constituents of interest, i.e., polyaromatic hydrocarbons (PAHs), using regulatory guidance, such as U.S. EPA's equilibrium partitioning methodology and equilibrium partitioning sediment benchmarks. Lines of evidence, including background contributions and bioavailability assessment, were employed successfully to develop PRGs for the Ohio River. The EPA methodology was used to account for the partitioning of PAHs in sediment between organic carbon, interstitial (pore) water, and benthic organisms. http://www.maep.org/docs/MAEP_Spring_09_Newsletter.pdf

St. Germain, R., Dakota Technologies, Inc.
The Michigan Environmental Professional, p 10-14, Spring 2009

Efficient remediation of former manufactured gas plants (MGPs), wood treater, and coking sites is contingent on accurate delineation of source-term DNAPLs, such as coal tar and creosote. They are "heavy" in terms of their relatively high proportion of large polycyclic aromatic hydrocarbons (PAHs) or similar cyclic compounds. Heavy NAPL tar/oil delineation and characterization traditionally involves sampling of subsurface soils using test pits, drill rigs or direct push sampling, logging of the boreholes by a geologist, and on- or off-site analysis of soil samples. The delineation process can be time-consuming, expensive, and dirty due to heavy NAPLs' odor and the difficulty associated with cleaning sampling equipment. The nature of these compounds can make it difficult to develop an accurate conceptual site model as heavy NAPLs often exist in both LNAPL and DNAPL phases. Because heavy NAPLs contain large PAH molecules, they are fluorescent, or spectroscopically active. The Tar-specific Green Optical Screening Tool (TarGOST®) exploits this fluorescent property, deriving the location and relative concentrations of heavy NAPLs in the subsurface by measuring their fluorescence. TarGOST® is essentially a front-face laser-induced fluorescence fluorometer that sends ultra-fast pulses (three billionths of a second in duration) of laser excitation light down a fiber-optic cable. The fiber optic delivers laser light through the direct push rod string and into a drive head containing a sapphire window, which allows the light to interact with the soil. The laser light strikes the soil matrix as the probe is steadily pushed or jack-hammered into the subsurface. Fluorescence emitted by heavy NAPL (and even some laser light that is scattered off the soil) is collected by a second fiber optic and returned uphole to the instrument for detection, analysis, and storage of data versus depth. The latest generation TarGOST® system employs a high-rate laser and detector that measure the fluorescence and scatter ~100 times each second as the probe is advanced to depths typically ranging from 25 to 50 feet. Maximum achievable depth is dependent on the geology. In addition to the device's capacity for formal chemical analysis, TarGOST® logs are useful for determining the distribution of the NAPL at a particular location, particularly when the logs are merged with GIS information and viewed collectively to convey the site's NAPL distribution relative to other features. http://www.maep.org/docs/MAEP_Spring_09_Newsletter.pdf

Fuller, C.C., S. Webb, J. Bargar, and D.L. Naftz.
American Geophysical Union, Fall Meeting 2009, abstract #H31E-0826, 2009

Permeable reactive barriers (PRBs) provide a means for passive remediation of dissolved groundwater contaminants and possibly an effective strategy for remediation of uranium (U) groundwater contamination, provided that long-term stability of the sequestered U can be achieved for the geochemical conditions of the aquifer following remediation. Understanding the chemical reaction mechanisms resulting in U uptake and PRB performance are critical to evaluating the potential for release of sequestered U and for improved design of remediation devices. Synchrotron X-ray techniques are being used to investigate U sequestration reaction mechanisms and biogeochemical processes in PRB materials recovered from a 9-year field demonstration of zero-valent iron (ZVI) and bone char apatite PRBs in a U-contaminated aquifer near Fry Canyon, Utah. X-ray microprobe mapping of iron phases shows that extensive secondary precipitation of mackinawite, siderite, and aragonite in the ZVI PRB has resulted from ZVI corrosion coupled with microbial sulfate reduction. Bulk U-EXAFS measurements and micron-scale U-oxidation state mapping indicates that U removal occurs largely by reduction and precipitation of a UO₂-like U(IV) phase on the ZVI surfaces, and that the sequestered U is often buried by the secondary Fe precipitates. These findings are significant in that the ongoing secondary-phase precipitation cements grains and fills internal porosity, resulting in the observed decreased PRB permeability, which limits subsequent U removal but likely also limits oxidative remobilization of U. In the bone char apatite PRB, elevated levels of U uptake were up to 20 times the maximum for U(VI) sorption by surface complexation expected for this material. XAS measurements show that the sequestered U is predominantly in the +4 oxidation state rather than +6, indicating a reduction process. Bulk U-EXAFS is consistent with the reduced U(IV) occurring as a sorbed species instead of forming biogenic urananite, and thus may be more likely to undergo re-oxidation and mobilization.

Taylor, C.R., P.B. Hook, C.A. Zabinski, and O.R. Stein.
Abstracts: Joint Conference of 26th Annual American Society of Mining and Reclamation and 11th Billings Land Reclamation Symposium, May 30-June 5, 2009, Billings, MT. p 81, 2009

Treatment wetlands (TWs) are widely used to address contaminants in domestic, agricultural, and industrial wastewater; stormwater runoff; and acid mine drainage. Currently, few plant species are used in the majority of TWs, and these are often non-native and/or weedy. The authors are working to identify native species for year-round use in cold-region TWs, particularly in the Rocky Mountain region, and to explore the basis of differences in performance. Project studies have included chemical oxygen demand (COD) removal from simulated wastewater in microcosms planted with monocultures of 19 species. Experiments were conducted over one year at seasonal temperatures of 4 to 24°C. With some species and in unplanted controls, COD removal declined at cold temperatures during dormancy, as expected with normal temperature dependence of microbial processes; however, COD removal was constant across seasons with the majority of species. Average COD removal exceeded 90% for Carex aquatilis, C. bebbii, C. praegracilis, C. utriculata, Schoenoplectus acutus, Juncus arcticus, J. torreyi, and Deschampsia cespitosa. Of these species, only S. acutus is widely used. In contrast, the widely used (and frequently invasive) species T. latifolia, P. australis, and P. arundinacea were somewhat less effective, with average COD removals of 84, 74, and 83%, respectively. Redox, sulfate, and root oxygen loss measurements suggest that plant-mediated oxygen transfer might explain the ability of some species to offset the effect of temperature on microbial processes and maintain high COD removal in all seasons. Results indicate that many non-weedy, regionally native species may be candidates for use in TWs or for rehabilitation of natural wetlands exposed to certain pollutants. In addition to the studied species, other obligate and facultative wetland species of the Cyperaceae and Juncaceae merit investigation.

Sun, Y., R.L. Gustavson, N. Ali, K.A. Weber, L.L. Westphal, and J.D. Coates.
Applied Microbiology and Biotechnology, Vol 84 No 5, p 955-963, Oct 2009

The response behavior of three dissimilatory perchlorate-reducing bacteria to environmental stimuli in the form of different electron acceptors (nitrate, chlorate, and perchlorate) was investigated with two different assays. The observed response was species-specific, dependent on the prior growth conditions, and inhibited by oxygen. Attraction toward nitrate was observed when Dechloromonas aromatica strain RCB and Azospira suillum strain PS were grown with nitrate. When D. aromatica and D. agitata strain CKB were grown with perchlorate, both responded to nitrate, chlorate, and perchlorate. When A. suillum was grown with perchlorate, the organism responded to chlorate and perchlorate but not nitrate. A gene replacement mutant in the perchlorate reductase subunit (pcrA) of D. aromatica resulted in a loss of the attraction response toward perchlorate but had no impact on nitrate response. Washed-cell suspension studies revealed that the perchlorate-grown cells of D. aromatica reduced both perchlorate and nitrate, while A. suillum cells reduced perchlorate only. Energy taxis is proposed as the underlying mechanism for the responses to (per)chlorate by D. aromatica. This demonstrates microbial attraction toward chlorine oxyanions and the unique ability of these organisms to distinguish structurally analogous compounds—nitrate, chlorate, and perchlorate—and respond accordingly. http://www.springerlink.com/content/lp63052q8m414953/fulltext.pdf

Kingston, J.T., P.R. Dahlen, and P.C. Johnson (Arizona State Univ.); E. Foote and S. Williams (Battelle Memorial Inst.). Environmental Security Technology Certification Program (ESTCP), Project ER-0314, 1,272 pp, Jan 2010

In this project, 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). This critical evaluation involved an empirical analysis of available design and operating information and performance results from pilot- and full-scale applications to see what experiences have been to date. The analysis was supplemented with post-treatment field sampling at selected sites to fill data gaps. This project made use of knowledge gained from other ESTCP and SERDP projects that investigated relationships between DNAPL architecture, treatment effectiveness, and groundwater mass discharge (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. The review identified the geologic settings in which these technologies were applied, 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 can be used by practitioners, regulators, and site owners to anticipate the likely performance of thermal-based DNAPL treatment technologies at their sites. The tables provide a tool where performance experience and theoretical bounds on performance expectations are linked to a small number of generalized geologic scenario site descriptors. The user can choose the generalized scenario that most closely resembles his site for a quick assessment of how the technology has been applied to date in that type of setting, the designs employed, the operating conditions, the performance monitoring on which results are based, the performance observed, indicators of success at other sites, and reasonable bounds on expected performance. Another product of this work, "State-of-the-Practice Overview of the Use of In Situ Thermal Technologies for NAPL Source Zone Cleanup," was developed to provide a useful tool and primer for program managers considering the use of thermal technologies at their sites. It condenses the 1,200-plus pages of this report into an 83-page format prepared for a program manager audience. http://www.estcp.org/Technology/upload/ER-0314-FR.pdf

Johnson, P., P. Dahlen, and J. Triplett Kingston (Arizona State Univ.); E. Foote and S. Williams (Battelle Memorial Inst.). Environmental Security Technology Certification Program (ESTCP), Project ER-0314, 83 pp, May 2009

In situ thermal technologies have undergone rapid development and application in recent years as they promise the potential of quicker and more thorough treatment of nonaqueous-phase liquid source zones. These technologies include electrical resistance heating, conductive heating/in situ thermal desorption, steam-enhanced extraction, radio frequency heating, and large-diameter auger soil mixing combined with steam/hot air injection. Each technology involves raising the subsurface temperature to achieve contaminant removal by some combination of the following: a) viscosity reduction to enhance mobility and liquid removal by pumping, b) vapor pressure increase (and in some cases in situ steam generation) to enhance removal by vapor extraction, and c) increased reaction rate (i.e., biodegradation or in situ oxidation) to destroy contaminants in situ. This document is intended to be a useful tool and primer for program managers considering the use of thermal technologies at their sites. The document is divided into three main sections: brief introductions to the most commonly applied in situ thermal technologies, summaries of key information gained from review of 182 thermal applications conducted from 1988 to 2007, and an appendix containing more in-depth discussion of thermal technologies authored by the technology vendors. http://www.estcp.org/Technology/upload/ER-0314-State-of-the-Practice%20O
verview.pdf

National Research Council, Board on Environmental Studies and Toxicology.
National Academies Press, Washington, DC. ISBN-10: 0-309-15094-9, 174 pp, 2010

Tetrachloroethene (PCE), the principal chemical used by drycleaners in the United States, is one of the most widely found groundwater and soil contaminants in this country, particularly in populated areas. The June 2008 EPA assessment reviewed by the National Research Council Committee found that existing (and already protective) standards for PCE exposure, particularly for the inhalation pathway, were not sufficiently protective. The NRC wrote, "the committee has identified concerns about some of the approaches that EPA used to evaluate the data on tetrachloroethylene and subjects about which inadequate information or rationales are used to support its risk assessment—factors that call into question the soundness and reliability of EPA's proposed reference values and cancer risk estimates for tetrachloroethylene." The report also states, "The committee found several parts of the draft IRIS assessment that could be improved on in the future. Such changes are not necessary for completing the current assessment but should be considered when tetrachloroethylene is re-evaluated in the future." The report also documents divisions about the assessment among the committee members, including an unusual dissenting statement and rebuttal. This report can be purchased or read on line at http://www.nap.edu/catalog.php?record_id=12863

U.S. DOE, Office of Environmental Management, 544 pp, Oct 2009

DOE's Office of Groundwater and Soil Remediation sponsored a technical workshop to assemble experts cognizant of technologies for addressing the challenges of cleaning up mercury in the environment, while promoting collaboration among scientists and engineers across the United States. The technical summit convened October 22 and 23, 2009, at Vanderbilt University in Nashville, Tennessee. The meeting brought together more than 70 experts from regulatory and other government agencies, national laboratories, academia, industry, and consulting to exchange information on recent research, field application, and policy developments. A variety of topics were discussed: mercury-related regulatory and public issues; mercury at the DOE Oak Ridge site, including history of use, mercury in fish, and past and planned remediation in creeks and storm sewer systems; mechanisms and controls on mercury biogeochemistry; transformation strategies for reducing formation of methylmercury; environment ecological risk assessment; site conceptual modeling of mercury; modeling of mercury transport pathways and associated risk; and innovative characterization and remediation technologies for mercury in sediments, soils, and water. The meeting agenda, abstracts, and many of the presentations are posted on DOE's Groundwater and Soil Remediation Web site under "Workshops and Events." http://www.em.doe.gov/EM20Pages/EM20ReferencePage.aspx

Mohr, T., J. Stickney, and W. DiGuiseppi.
CRC Press, Boca Raton, FL. ISBN: 9781566706629, 550 pp, 2010

A ubiquitous, largely overlooked groundwater contaminant, 1,4-dioxane escaped notice by almost everyone until the late 1990s. While some dismissed 1,4-dioxane because it was not regulated, others were concerned and required testing and remediation at sites they oversaw. Drawing years of 1,4-dioxane research into a convenient resource, this book profiles the nature of 1,4-dioxane and several dozen other solvent stabilizer compounds, reviews the history of the contaminating chemical's use in the industrial workplace, and describes how those uses impart chemical characteristics to the waste that affects its fate and transport properties. The book examines the uses, environmental fate, laboratory analysis, toxicology, risk assessment, and treatment of 1,4-dioxane in extensive detail. It also describes the controversy over interpretation of 1,4-dioxane's toxicology and associated risk, as well as the corresponding disparity in state regulation of 1,4-dioxane. Filled with case studies, equations, tables, figures, and citations, the book provides passive and active remediation strategies and treatment technologies for 1,4-dioxane in groundwater.

International Phytotechnology Society, 144 pp, 2009

The International Phytotechnology Society sponsored the 6th International Phytotechnologies Conference to help regulators, researchers, consultants, and site owners understand which technologies using plants for environmental goals are currently effective, how best to integrate research science and field application, and what questions need further research. Phytotechnologies have been applied successfully in many places, but many questions remain. Topics of particular interest include phytoremediation projects, phytotechnologies for use in developing economies, ecorestoration and habitat creation, biofuels, green-roof technology, carbon sequestration, fate or transport of contaminants through plants and associated eco-risk, vegetative covers, and constructed wetlands. http://www.phytosociety.org/Phyto%20Society%20-%20Awards_Events_Conferen
ces.htm#PAST_SOCIETY_CONFERENCES

U.S. EPA, Office of International Affairs, 2009

EPA's Office of International Affairs Organized the Forced Air Remediation Workshop in Taipei to deliver expert training based on slide presentations to the Environmental Protection Administration in Taiwan. The workshop focused on the correct and effective application of forced-air technologies for the removal of vapor-phase contaminants. The first three training modules discuss technology selection, sampling and monitoring considerations, and how to make the cleanup more environmentally friendly. The five technology modules address applicability, configurations, design considerations and data needs, operational strategies, operating principles, limitations, cross-sections and schematics, and construction and startup/operation.
  •   Section 1: Air-Based Remediation Technology Selection Logic (25 slides) http://clu-in.org/download/contaminantfocus/dnapl/Treatment_Technologies
/ABR09-8-Logic.pdf

  •   Section 2: Sampling and Analysis Relevant to Air-Based Remediation Technologies (67 slides) http://clu-in.org/download/contaminantfocus/dnapl/Treatment_Technologies
/ABR09-1-Analysis.pdf

  •   Section 3: Sustainable Remediation and Air-Based Technologies (7 slides) http://clu-in.org/download/techfocus/ABR09-7-Sustainability.pdf

  •   Section 4: Soil Vapor Extraction (82 slides) http://clu-in.org/download/techfocus/sve/ABR09-2-SVE.pdf

  •   Section 5: Bioventing (37 slides) http://clu-in.org/download/techfocus/bioventing-biosparging/ABR09-3-Biov
enting.pdf

  •   Section 6: In Situ Air Sparging (41 slides) http://clu-in.org/download/techfocus/air-sparging/ABR09-4-AS.pdf

  •   Section 7: Multi-Phase Extraction and Product Recovery (57 slides) http://clu-in.org/download/techfocus/mpe/ABR09-5-MPE.pdf

  •   Section 8: Thermal Systems (74 slides) http://clu-in.org/download/techfocus/thermal/ABR09-6-Thermal.pdf

Mayer, J.
SRNL-RP-2009-00845, 54 pp, Sep 2009

The DOE-EM Long-Term Monitoring Technical Forum was held February 11-12, 2009, sponsored by Savannah River National Laboratory and DOE's Office of Environmental Management (EM) Engineering and Technology Program (EM-22). The Technical Forum was attended by 57 professionals with a focus on identifying areas of opportunity that would advance the transition of the current practices to a more effective strategy for long-term monitoring (LTM). The specific objectives were to identify (1) technical targets for reducing EM costs for life-cycle monitoring; (2) cost-effective approaches and tools to support the transition from active to passive remedies at EM waste sites; and (3) specific goals and objectives associated with lifecycle monitoring initiatives. The first breakout session focused on the integration and improvement of LTM performance measurement and monitoring tools that deal with parameters such as ecosystems, boundary conditions, geophysics, remote sensing, biomarkers, ecological indicators and other types of data used in LTM configurations. Three investment sectors were identified in this session. The second breakout session was focused on identifying new and inventive LTM systems that address the framework for interactive parameters like infrastructure, sensors, diagnostic features, field-screening tools, state-of-the-art characterization monitoring systems/concepts, and ecosystem approaches to site conditions and evolution. Two investment sectors were identified in this session. The last breakout session examined the development and implementation of novel information management systems for LTM, including techniques to address data issues, such as efficient management of large and diverse datasets; consistency and comparability in data management and incorporation of accurate historical information; data interpretation and information synthesis, including statistical methods, modeling, and visualization; and linkage of data to site management objectives and leveraging information to forge consensus among stakeholders. One investment sector was identified in this session. http://www.osti.gov/bridge/product.biblio.jsp?query_id=4&page=0&osti_id=
965900

Crowley, K.D., National Research Council.
National Academies Press, Washington, DC. ISBN: 10: 0-309-10821-7, 86 pp, 2010

DOE's Office of Environmental Management (EM) is developing a technology roadmap to guide planning and possible future congressional appropriations for its technology development programs. EM asked the National Research Council of the National Academies to provide technical and strategic advice to support the development and implementation of this roadmap, specifically by undertaking a study that identifies principal science and technology gaps and their priorities for the cleanup program based on previous National Academies reports, updated and extended to reflect current site conditions and EM priorities and input from key external groups, such as the Nuclear Regulatory Commission, Defense Nuclear Facilities Safety Board, Environmental Protection Agency, and state regulatory agencies. In response, Part 1 of this book provides a high-level synthesis of principal science and technology gaps identified in previous NRC reports. Part 2 summarizes a workshop meant to bring together the key external groups to discuss current site conditions and science and technology needs. This report can be purchased or read on line at http://books.nap.edu/catalog.php?record_id=11932

Waugh, J. (S.M. Stoller Corporation); C. Benson (University of Wisconsin); B. Albright (Desert Research Institute); G. Smith (Geosmith Engineering).
U.S. DOE, Office of Legacy Management, Ongoing Research and Projects. 3 pp, 2009

DOE's Office of Legacy Management (LM) has constructed a test facility at the Grand Junction Disposal Site to evaluate a method for renovating a conventional, low-permeability cover. The purpose of the study, the Renovated Evapotranspiration Cover Assessment Project (RECAP), will demonstrate an inexpensive way to improve long-term surveillance and maintenance (LTS&M) of disposal cell covers. LM believes that cover renovation could lead to a reduction in risk over the long term. Conventional disposal cell covers at many LM sites rely on compacted soil layers (CSLs) to limit water percolation into underlying waste. LTS&M follow-up investigations have shown that the permeabilities of CSLs are often much higher than design targets, sometimes by several orders of magnitude. Similar results were found in a nationwide U.S. EPA study. Causes for greater-than-expected permeability include (1) unanticipated ecological consequences of designs that encourage biointrusion, desiccation, and freeze-thaw cracking, (2) differences between laboratory and field measurements of hydraulic conductivities, and (3) retention of borrow soil structure (clods) during construction and natural soil formation processes after construction. Studies by DOE, EPA, and others have shown that alternative evapotranspiration (ET) covers work well at arid and semiarid sites. ET covers consist of thick, fine-textured soil layers that store precipitation in the root zone where it can be removed seasonally by plants. The RECAP study is evaluating a renovated cover design for the Grand Junction Disposal Site. The existing cover consists of four layers: a low-permeability radon barrier (a CSL), a frost protection layer, a sand and gravel bedding layer, and a layer of durable basalt riprap. Construction of test covers in the RECAP lysimeters closely followed as-built designs for the Grand Junction disposal cell, including the use of similar heavy equipment. The renovation treatment to be imposed on one of the two lysimeters after baseline hydrologic conditions have been established will involve ripping and mixing the rock, drainage, and frost protection layers, and planting native shrubs in the rip rows. After several years of monitoring and comparing the original design with the renovated design, LM will weigh the results of the study in future LTS&M decisions for Grand Junction and other sites with conventional covers. Research note posted at http://www.lm.doe.gov/default.aspx?id=311

Heiser, J. and T. Sullivan.
BNL-82389-2009, 70 pp, June 2009

In the event of the release of a large-scale radiological dispersion device (RDD), long-term recovery will require decontamination of a substantial amount of diverse material. This report provides an overview of radiological decontamination methods. The two major approaches are chemical and mechanical decon. Chemical decon approaches dissolve the contaminant in solution and can be tailored for specific radionuclides. Mechanical decon approaches release the radionuclides through mechanical agitation or physical removal. Several techniques—strippable coatings, paint thinners, and washing—combine mechanical and chemical techniques, offering a compromise between total removal in abrading technologies and pure chemical treatment. The data show that contaminants migrate into porous materials and become much more difficult to remove with time. A literature review identified U.S. companies with radiological decon experience and culminated in a table that lists the larger companies (no preference should be inferred) with vendor information, products and services, and contact information. More technology development needs to be directed toward adapting cleanup technologies from other industries that have to deal with urban and residential environments and materials, such as graffiti and soot removal. The challenges of multiple material surfaces, multiple property owners, the need for quick restoration of area functionality, and societal impacts make cleanup of an RDD event substantially different and much more difficult than decontamination of nuclear facilities. http://www.osti.gov/bridge/product.biblio.jsp?query_id=3&page=0&osti_id=
965879