U.S. Army Corps of Engineers, Omaha District.
Federal Business Opportunities, FBO-2426, Solicitation W9128F-08-R-0045, 2008

The U.S. Army Corps of Engineers, Omaha District, intends to solicit and award one firm fixed-price contract for environmental remediation services at Cape Canaveral Air Station, Florida. This action will be initiated under NAICS Code 562910 and set aside for qualified small business concerns. The actual scope of services will be released with the solicitation on or about 25 July 2008. Briefly, the proposed industrial area regional treatment basin planned to be constructed as a regional stormwater improvement project in the industrial area of the facility will manage (capture, route, and treat) stormwater runoff and prevent (capture and treat) ground water contaminated with chlorinated solvents in the facility industrial area from discharging to the Banana River Lagoon. Aeration, volatilization, and phytoremediation will be the primary methods used to remove volatile organic compounds (VOCs) from the basin water prior to discharge to the Banana River Lagoon. The proposed improvement plan establishes two wet detention stormwater management areas. VOC-contaminated ground and surface water will be captured and treated using the following processes: (1) air stripping/aeration/agitation treatment via a SolarBee (or equivalent) treatment unit; (2) air stripping/aeration/agitation treatment via a solar-powered aeration system; (3) phytoremediation via wetland plant species uptake; (4) photoionization/volatilization via sunlight surface exposure; (5) evapotranspiration via atmospheric conditions; and (6) air stripping/treatment via agitation of surface-water flow across various surface-water features and structures throughout the basin treatment systems. If the proposed basin treatment system is unable to remove VOC contaminants effectively, an existing blower system can be retrofitted to provide more significant air stripping treatment in the secondary basin prior to discharge to the wetland system. All information required for submission of an offer will be identified in the RFP when it is issued electronically through the Army Single Face to Industry Acquisition Business Web site at https://acquisition.army.mil/asfi/
and the Federal Business Opportunities Web site at http://www.fedbizopps.gov/
FBO notice and contact information at https://www.fbo.gov/?s=opportunity&mode=form&id=d803ab2fe2532fb8005ce356
30885541&tab=core&_cview=0

Olympic Delivery Authority, 9 May 2008

Nearly all (98%) of the 2.5 km² Olympic Park, the official site of the London 2012 Olympic and Paralympic Games, has now been investigated for contamination. According to the Olympic Delivery Authority (ODA), the findings are in line with expectations. All of the 'Big Five' venue sites are clear ahead of the start of the 'Big Build' this summer, and two-thirds of the whole site, over one million square meters in total, has been cleared. Over the past century, heavy industrial use has contaminated the Olympic Park area with gasoline, oil, tar, heavy metals (e.g., arsenic and lead), and very low-level readings of radium in small isolated areas. Additionally, four hectares (around ten football pitches) of soil are contaminated with Japanese Knotweed, a highly invasive and tough-to-kill plant. Japanese Knotweed is so tough that it must be either treated with herbicide over several growing seasons or macerated into tiny pieces and then buried on site encased in secure membrane root barriers so deep that it cannot re-grow. Treatment is well underway. About 1.5 million tonnes of contaminated soil are being cleaned for reuse, creating the platform for venues and parklands. Five soil washing machines have been installed on the Olympic Park to wash, sieve, and shake out the contaminants. Naturally occurring microorganisms are also helping to clean nearly 50,000 tonnes of contaminated soil by eating petrol and diesel in large ex situ piles on site. Over 120,000 tonnes of materials from a 100 year-old dump on the Velodrome site are being sorted so that they can be either reused on site or recycled off site. The aim of the ODA is not only to clean up neglected and contaminated land for the Games but also to use the latest technology to do it in a sustainable way, reuse materials wherever possible, and landfill the minimum amount of material. News release at http://www.london2012.com/news/media-releases/2008-05/olympic-park-clean
-up-on-track-ahead-of-big-build-start.php

DiMichele, R.E., USAEC Public Affairs.
U.S. Army Environmental Command News Release, 16 Apr 2008

The Hawaii Army National Guard (HIARNG) at Fort Ruger took only four months to restore Diamond Head Crater to its pristine natural condition in preparation for its conversion to a state monument. For decades, Diamond Head Crater has been the first natural feature that nearly seven million visitors see annually on approach to the Hawaiian Islands, via ship or airplane. Located in Honolulu and part of Fort Ruger since 1909, the Diamond Head military complex was used by the National Guard for pistol and rifle training. Over the decades, this training has caused tons of ammunition fragments to be deposited in the soil of the firing ranges. In a concerted effort to leave Diamond Head in better condition than when it was given to the U.S. Army, HIARNG undertook a comprehensive cleanup program to prepare Diamond Head for its conversion to a state monument. In a matter of months and without once closing the park to the public, the HIARNG Diamond Head restoration staff removed and recycled over 14 tons of particulate metal and cleaned 30,000 tons of soil using a soil-washing machine powerful enough to wash the soil thoroughly after only one pass through the system. The recycling efficiency of the soil-washing equipment reduced the need to tap into fresh-water resources. Invasive plant species at Diamond Head also were removed to promote native vegetation growth. Prescribed burning to control invasive plants is forbidden in the area, and the Guard restoration staff manually dug up the offensive plants to avoid using chemical pesticide sprays. For their effort to remediate and restore the Diamond Head Crater, the HIARNG at Fort Ruger will receive the Army's highest honor in environmental stewardship: the Secretary of the Army Environmental Award.

Caraballo, M.A. and F. Macias (Univ. of Huelva, Huelva, Spain); T.S. Rtting (Newcastle Univ., UK); J.M. Nieto (Univ. of Huelva); and C. Ayora (Inst. of Earth Sciences Jaume Almera CSIC, Barcelona Spain). The 18th Annual V.M. Goldschmidt Conference, 13-18 July 2008, Vancouver, Canada. Abstracts, p A135, 2008

To overcome problems of clogging commonly presented by passive treatment systems exposed to high metal concentrations in acid mine drainage (AMD), a novel dispersed alkaline substrate (DAS)-based system has been developed that combines of a mixture of fine-grained limestone as a reactive material and wood chips as a coarse inert matrix. Mina Esperanza is an underground sulfide mine that was in operation during the first half of the 1900s. After closure, the mine was flooded, and a polluted creek flows from the main adit into the Odiel River, with deleterious impact on water quality. A full-scale passive treatment system at this site consists of an open channel connecting the adit to the DAS-reactive pool, followed by aeration cascades and a sedimentation pond. This treatment system has a small footprint: the DAS reactive pool occupies an area of 15 m length x 8 m width x 4 m depth, followed by aeration cascades and a sedimentation pond covering an area of 10 m length x 3 m width x 2 m depth. AMD at the exit of the adit has a pH of 2.66 to 2.95; net acidity of 2,200 to 2,800 mg/L as calcium carbonate; 750 to 950 mg/L Fe (95% ferrous iron); 3,500 to 4,200 mg/L sulfate; 125 to 160 mg/L aluminum; 15 to 20 mg/L zinc and copper; and 0.1 to 1 mg/L arsenic, lead, copper, cadmium, and vanadium. At the system outflow, the pH rises to 5.9 to 6.3, and net acidity falls to 750 to 900 mg/L as calcium carbonate. The system has been working for a period of 11 months, treating a mean inflow of 0.5 L/s with an acidity load of 900 g/m²/day as calcium carbonate. This loading rate is much higher than the rate recommended for conventional passive treatment systems, such as reducing and alkalinity producing systems. These results indicate that high-acidity AMD can be treated within a relatively small area. The system eliminates a net acidity of 1,500 mg/L as calcium carbonate from the inflow water and removes 75 to 100% of most of the metal contaminants, 45% of the iron, and 20% of the sulfate.

Enfield, C.G. (U.S. EPA, Cincinnati, OH); B.K. Lien (Pegasus Technical Services, Inc., Cincinnati, OH).
Report No: EPA 600-R-08-068, 109 pp, June 2008

Laboratory and field studies have shown that it is possible to degrade most fuel components under oxidizing conditions. The spread of soluble fuel components released to ground-water environments often is enhanced because ground water cannot supply oxygen at a rate equal to the demand of the dissolved fuel. This report details an evaluation of the feasibility of treating fuel components using a control system in the vadose zone (i.e., soil above the water table) to maintain an oxidizing state without artificial addition of oxygen. The study was conducted for more than a year at Port Hueneme, California, in an area formerly contaminated by a fuel spill. Because little contamination remained in the ground water when the study was performed, it was not possible to evaluate the chemical performance of the system, and the scope of the study therefore was limited to evaluating the field reliability of a remotely operated infiltration gallery. The results showed that it was possible to operate the system remotely with very little intervention from a field technician. None of the problems normally associated with infiltration galleries plugging from biological growth was observed, likely due to the draining of the distribution lines between each water application cycle. Report at http://www.epa.gov/nrmrl/pubs/600r08068/600r08068.html

Solc, Jarda, Univ. of North Dakota, Energy & Environmental Research Center.
Report No: 2007-EERC-12-07, 300 pp, Dec 2007

The performance of alternative technologies for remediation of soil and ground water impacted by a hydrocarbon-contaminated coal seam was evaluated in Garrison, North Dakota, following the September 2005 release of an estimated 30,000 gallons of premium gasoline from an oil company facility. Site investigation confirmed the presence of free product in abandoned mine cavities and high concentrations of residual gasoline-based contaminants. Benzene concentrations in the ground water exceeded 70,000 µg/L. Geotechnical characteristics of the fractured coal seam expedited the rapid off-site migration of contamination. The affected zone covers an area of about 40 acres, with hot spots identified at the location of original release, the downgradient west corner, and in mining cavities intercepting the plume south of the release area. Regardless of the exposure mechanism (free, dissolved, or vapor phase), results of laboratory tests confirmed that secondary release of gasoline-based compounds from contaminated coal to water reached concentrations documented from the source areas. Laboratory tests indicated low risks associated with spontaneous ignition of gasoline-contaminated coal. Soil vapor extraction (SVE) and multiphase extraction (MPE) pilot tests confirmed high contaminant recovery efficiency at all three of the identified hot spots. The extraction of a total of 3,500 gallons (13.3 m³) of contaminated ground water and over 430,000 ft³ (12,200 m³) of soil vapor during vacuum-enhanced recovery testing conducted July 17 to 24, 2007, resulted in the removal of about 1,330 lbs of hydrocarbons, equivalent to about 213 gallons of product. The suggested remedial strategy is based on contaminant recovery and in situ degradation using a combination of thermally enhanced SVE in the source area, MPE transitioned to SVE in saturated impacted areas, and high-volume low-vacuum extraction from mining cavities based on a pioneering concept of controlled "draft and channel" extraction technology. To control cleanup costs within this large contaminated area, the proposed stationary SVE systems should be designed as modular components that can be combined with mobile, high-vacuum MPE systems. This design approach is expected to achieve high contaminant recovery efficiency while maintaining operational flexibility. A supplemental delineation of the cavities within the abandoned mine should be an integral part of the cleanup process because of the effect of the cavities on contaminant distribution within the impacted area. Report at http://www.osti.gov/bridge/purl.cover.jsp?purl=/926664-O629FP/

Federal Remediation Technologies Roundtable Cost and Performance Database, 2007

In the 1940s, the LF-08 site was a landfill covering approximately 25,000 square ft in area and containing sludge, solvents, paint wastes, lubricating and cutting oils, and dry cleaning filters and filtrates. The site currently is used as a recycling center for the Air Force Base. Trichloroethene (TCE) and cis-1,2-dichloroethene (cis-1,2-DCE) have been identified as site contaminants. Enhanced in situ anaerobic bioremediation using a vegetable oil substrate was selected as the treatment technology for a pilot study. Geochemical measurements of the subsurface indicated that the vegetable oil emulsion did create anaerobic conditions within the treatment zone; however these areas were sporadic throughout the treatment zone due to substrate distribution and variability in the conditions. Concentrations of TCE increased after injection, and DCE remained stable or increased slightly. Vinyl chloride was not found, although ethene did increase approximately one order of magnitude. The duration of the monitoring period was considered insufficient to observe the dechlorination of chlorinated solvents because of the low ground-water flow rate and low sediment permeability. The total cost for the pilot test at LF-08 was $117,300, which covered $75,700 for capital costs and $41,600 for sample collection and analysis of two monitoring events. Case study at http://costperformance.org/profile.cfm?ID=409&CaseID=407

Kim, J., H. Kang, W. Choi, S. Kim, and M. Lee, Pukyong National Univ., Daeyondong, Namgu, Busan, Korea. The 18th Annual V.M. Goldschmidt Conference, 13-18 July 2008, Vancouver, Canada. Abstracts, p A471, 2008

A pilot-scale application of in situ flushing coupled with high-pressure air injection was performed to remediate soil and ground water contaminated with bunker fuel oil types A and C. The average total petroleum hydrocarbon (TPH) concentration in the soil of the former roofing tile manufacturing facility was 3,449.95 mg/kg, which greatly exceeded the Korean regulatory level of 500 mg/kg. The pilot test was conducted in an area 15 m x 19 m x 6 m composed mostly of heterogeneous sandy and gravel-sandy soils contaminated to a depth of 4 to 5 m. The system incorporated 14 injection wells, three extraction wells, and a trench at the right boundary of the site. After the injection of a 2% surfactant solution, high-pressure air injection was used to mobilize the solution into pore spaces underground. The effluent was subjected to a chemical treatment process that separated the oil for recycling. The pilot test removed a total of 3.6 tons of petroleum hydrocarbons (about 86% of the oil estimated) from the plot and lowered the soil TPH concentration below 500 mg/kg. The authors determined that optimum performance was obtained at a surfactant solution injection rate of 11 L/min and an air injection rate of 25 kg/cm². The results indicate that in situ flushing coupled with high-pressure air injection has great potential for remediation of soil contaminated with bunker fuel oil.

U.S. EPA Region 6 Fact Sheet, 3 pp, June 2008

U.S. EPA signed the Record of Decision for the Grants Chlorinated Solvents Plume Site on June 30, 2006. The shallow aquifer at the site is contaminated with chlorinated solvents, such as tetrachloroethene, trichloroethene, and cis-1,2-dichloroethene. The selected remedy calls for the use of very aggressive thermal and chemical dechlorination technologies to address shallow and deep ground-water contamination, plus mitigation of vapor intrusion in buildings above the defined plume. The State of New Mexico supports the selected remedy. EPA currently is working on the remedial design phase of the project. Ground-water injection and monitoring wells were installed, and pilot testing of the selected ground-water remedy began in May 2007. Both in situ chemical oxidation and enhanced reductive biobarrier pilot tests have been initiated. Ground-water monitoring will be conducted quarterly over the next twelve months to determine the effectiveness of the selected remedy. EPA also is testing homes located above the plume to design vapor intrusion mitigation systems (VIMS). The remedial design for installing the VIMS is in the final stages. EPA plans to install the mitigation systems in affected homes in 2008. Fact sheet at http://www.epa.gov/earth1r6/6sf/pdffiles/0605144.pdf

Wellman, D.M., E.M. Pierce, E.L. Richards, B.C. Butler, K.E. Parker, J.N. Glovack, S.D. Burton, S.R. Baum, E.T. Clayton, and E.A. Rodriguez.
Report No: PNNL-16683, 93 pp, 2007

This report presents results from bench-scale treatability studies conducted under site-specific conditions. The investigators aim to optimize the polyphosphate amendment for implementation of a field-scale technology demonstration to treat aqueous uranium within the 300 Area aquifer of the Hanford site. The proposed technology works by forming phosphate minerals (autunite and apatite) in the aquifer, which directly sequesters the existing aqueous uranium in autunite minerals and precipitates apatite minerals for sorption and long-term treatment of uranium migrating into the treatment zone, thereby reducing current and future aqueous uranium concentrations. The lab treatability testing approach consists of conducting studies with site sediment under site conditions to develop an effective chemical formulation for the polyphosphate amendments and evaluate the transport properties of these amendments. Phosphorus-31 nuclear magnetic resonance was utilized to determine the effects of Hanford ground water and sediment on the degradation of inorganic phosphates. Static batch tests were conducted to optimize the composition of the polyphosphate formulation for the precipitation of apatite and autunite, as well as to quantify the kinetics, loading, and stability of apatite as a long-term sorbent for uranium. Dynamic column tests supported optimization of the polyphosphate formulation for emplacement within the subsurface and the formation of autunite and apatite, and dynamic testing quantified the stability of autunite and apatite under relevant site conditions. Results of this investigation provide valuable information for the full-scale design to remediate uranium contamination in the 300 aquifer. Available at http://www.pnl.gov/publications/abstracts.asp?report=228484

Meeroff, D.E., F. Gasnier, and C.T. Tsai, Florida Atlantic Univ.
Univ. of Florida, Hinkley Center for Solid and Hazardous Waste Management, Report 0632018, 225 pp, Jan 2008

The objective of this two-year study was to develop two new energized processes for leachate treatment and assess their sustainability (performance, risk, and cost) as compared to currently available treatment alternatives. The first task was to examine the literature on energized alternatives for detoxification and treatment of leachate, collect leachate quality data, identify issues/trends associated with long-term leachate management, and prepare a list of energized alternatives ranked according to environmental sustainability, efficiency, risk, and economic factors. During the first year of the project, leachate was characterized, and the study of existing treatment techniques was completed. Task two was dedicated to the design of the photochemical iron-mediated aeration (PIMA) and TiO₂/magnetite photocatalysis reactors. Only the PIMA process was investigated during the first year. In task three, the processes were tested on (1) an influent leachate solution containing a single unique component, (2) a solution containing a mixture of components, and (3) real leachate collected from the Solid Waste Authority of Palm Beach County. The final task was to compare the PIMA and TiO₂/magnetite catalysis processes with other viable technologies and then to prepare preliminary cost analyses and risk assessments on selected technologies to provide a Florida-specific matrix of innovative, economical, and environmentally sound engineering alternatives to aid solid waste management personnel in decision-making. Report at http://www.hinkleycenter.com/publications/Meeroff_Year2Investigation_of_
Energized_Options.pdf

Thibodeaux, L.J., K.T. Valsaraj, R. Ravikrishna, K. Fountain, and C.L. Price.
Report No: ERDC/EL TR-08-17, 142 pp, Apr 2008

In an investigation of specific factors that control air emissions associated with the dredging of sediments and related confined disposal facility (CDF) operations, three primary objectives were proposed. The first objective involved measurements of Henry's Law constants and sediment/water desorption constants for various chemicals from IHC sediments. The second involved measurement of volatile emissions from IHC sediments exposed to air. The third addressed the reformulation of models developed for estimating air emissions from contaminated sediments dredging and handling activities. The three separate reports produced during the course of these investigations have been compiled into this final report. Report at http://el.erdc.usace.army.mil/elpubs/pdf/trel08-17.pdf

Lazareva, O. and T. Pichler, Univ. of South Florida, Tampa.
The 18th Annual V.M. Goldschmidt Conference, 13-18 July 2008, Vancouver, Canada. Abstracts, p A522, 2008

A study was conducted to investigate the potential of a constructed wetland for improving the chemical composition of waste and surface waters in a phosphate mining area used for clay settling and sand tailings in Polk County, Florida. A mix of industrial wastewater from a power plant, city effluent, rain, and excess surface water was passed through a constructed wetland/filter basin (CW/FB) treatment system approximately 1,500 m in length. The wetland vegetation was allowed to evolve naturally. After passage through the wetland, the water was filtered through sand to eliminate pathogens, color, and odor. Monitoring was carried out for 18 months To evaluate the CW/FB performance through the dry and rainy seasons, water samples were taken bi-monthly over a period of 18 months, and six monitoring wells located along the wetland were sampled monthly to evaluate possible ground-water input into the wetland. Preliminary monitoring results showed the following changes in quality from the cooling pond water to the water exiting the CW/FB system: (1) a change in pH from 9-9.5 to 7-6.5; (2) a decrease in water temperature of as much as 10°C; (3) a decrease of dissolved oxygen from 15 to <2 mg/L; (4) reduction of arsenic from 5 to <0.5 µg/L; (5) an increase of sulfur from <1 to >2,000 µg/L; and (6) reduction of fecal (370 to <2 #/100mL) and total coliform (2,000 to <100 #/100mL). Despite large seasonal variations with respect to temperature, rainfall, and humidity, the chemical/microbiological composition of treated water remained relatively constant.

Stollenwerk, K.G. (USGS, Denver, CO); A.P. Paul, A.H. Welch, and D.K. Maurer (USGS, Carson City, NV). The 18th Annual V.M. Goldschmidt Conference, 13-18 July 2008, Vancouver, Canada. Abstracts, p A903, 2008

A potentially cost-effective alternative to traditional above-ground treatment for arsenic (As) exceeding 10 µg/L is to lower As concentrations within the aquifer by increasing As sorption through in situ alteration of the geochemical environment. Scientists plant to test the effectiveness of in situ remediation in cross-flow field experiments at a site in Carson Valley, Nevada. Reducing conditions are dominant in this aquifer: sediments are gray in color, ground water contains <1 mg/L oxygen, and As concentrations are about 30 µg/L as As(III). Ground water will be pumped to the surface and modified by addition of 7 mg/L ferrous iron, 6 mg/L oxygen, and hydrogen chloride to a pH of 5.5. The modified ground water will be injected into a well upgradient from a monitoring well. Oxidation of iron and precipitation of hydrous ferric oxide (HFO) are expected to decrease arsenic concentrations by adsorption and coprecipitation. In laboratory column experiments conducted to quantify the significant reactions in this system, an eluent solution similar to the proposed field injectate was eluted through a column containing a core collected from the aquifer, and breakthrough of constituents was monitored for 150 pore volumes. Iron was oxidized rapidly at the influent end of the column, and iron concentrations in leachate never exceeded the detection limit of 0.01 mg/L. The reddish brown color that developed in the sediment evidenced precipitation of HFO, but flow rates suggested that plugging of sediment pores by HFO did not occur. Arsenic concentrations in the leachate decreased rapidly from 30 µg/L to 8 µg/L during the first 10 pore volumes, after which As concentrations stabilized between 7 and 8 µg/L for the duration of the experiment. These results indicate that in situ remediation in this aquifer could decrease As concentrations successfully to levels below the drinking water standard.

Sasaki, K., S. Nukina, W. Wilopo, and T. Hirajima, Kyushu Univ., Fukuoka, Japan. The 18th Annual V.M. Goldschmidt Conference, 13-18 July 2008, Vancouver, Canada. Abstracts, p A824, 2008

Immobilization of arsenate in ground water contaminated by acid mine drainage (AMD) was investigated in a permeable reactive barrier (PRB) column containing granulated blast furnace slag (GBFS). In batch tests, the GBFS exhibited by two orders of magnitude a lower sorption capacity for arsenate than zero-valent iron (ZVI) in the amount of arsenate sorbed per unit surface area of sorbent (mmol/m2); however, the amount of arsenate sorbed per unit amount of sorbent (mmol/kg) was comparable because of much higher porosity in the GBFS. Column performance showed that As at 15 mg/L fell to <0.4 mg/L for more than 18 pore volumes (pv) in the GBFS PRB by sorption, co-precipitation, and (presumably) formation of hydrated calcium arsenate. In the ZVI PRB, As fell to <0.04 mg/L for more than 17 pv, likely by co-precipitation with iron (oxyhydro)oxides. Additionally, manganese at 15 mg/L also decreased to <0.3 mg/L in both the ZVI and GBFS PRB columns, probably due to sorption and precipitation of oxides and carbonates. The investigators estimated that 1 mg/L of arsenate could be treated for 30 years using 10(v/v)% of the GBFS in a PRB at a thickness of 1 m, indicating that the effective lifespan of GBFS is comparable with that of ZVI. The GBFS compensates for its low reactivity with high porosity and low density. This reuse of an industrial waste illustrates the potential for reactive material alternatives to ZVI for immobilization of arsenic and manganese in acid mine drainage.

Kim, J., A. Choi, J. Kim, I. Kim, and M. Lee, Pukyong National Univ., Daeyondong, Namgu, Busan, Korea. The 18th Annual V.M. Goldschmidt Conference, 13-18 July 2008, Vancouver, Canada. Abstracts, p A471, 2008

Column experiments were performed to investigate the efficiency of lime and limestone for reducing arsenic (As) leaching from contaminated soil collected in farmland connected to the abandoned Samkwang mine. The initial As concentration was 40.99 mg/kg. A physical model was designed for the assessment of As soil leaching under the influence of artificial rainfall. In the mixing treatment process, either 1 and 2 wt% of granulated lime or 2 and 5 wt% of granulated limestone was mixed with the contaminated soil and packed in the column. From the top of the column, 1,092 mL of artificial rain was sprayed uniformly on the top of the column every 24 hr at a constant rate of 100 mL/min for 20 days, representing 20 years of soil leaching in farmland. Leached water was drained from the bottom of the column, and its As concentration was analyzed to investigate the decrease in leaching amount effected by lime and limestone. For 1 and 2 wt% of lime, As concentration of leached water fell by 95 and 96%, respectively. For 2 and 5 wt% of limestone, As concentration of leached water decreased by 92 and 76%, respectively. When 1 wt% of granulated lime and 2 wt% of granulated limestone were mixed, As concentration in leachate decreased by 96%.

Roldan-Martin, A. and G. Calva-Calva. (Centro de Investigacion y Estudios Avanzados, IPN, Mexico); N. Rojas-Avelizapa (Inst. Mexicano del Petroleo, Mexico); Ma.D. Diaz-Cervantes and R. Rodriguez-Vazquez (IPN, Mexico).
International Biodeterioration and Biodegradation, Vol 60 No 1, p 35-39, 2007

Stimulation of microbial activity that results in the biodegradation of petroleum hydrocarbons can be achieved at many sites by the addition of compost consisting of mixtures of agro-industrial residues, such as chopped wheat straw and low-quality coffee beans. This paper describes the use of solid culture with small amounts of low-quality raw coffee beans for the removal of petroleum hydrocarbons at a concentration of 58,000 mg/kg total petroleum hydrocarbon (TPH) from a weathered soil. The researchers evaluated soil/coffee bean ratios of 98:2, 96:4, 94:6, and 92:8, at a C:N:P ratio of 100:10:1, 20% humidity, and 28°C, for periods of 15, 60, and 90 days. They obtained the highest TPH removal (63%) with a soil/bean ratio of 98:2 over 15 days, corresponding with the highest rates of microbial respiration and the greatest increases in bacterial and fungal counts. Scanning electron microscopy showed high fungal colonization of coffee beans, with Mucor sp., Aspergillus sp., Aspergillus niger, and Penicillium sp. growing on TPH as the sole carbon source.

Delille, D. (Univ. P. et M. Curie UMR-CNRS, France); F. Coulon (Univ. of Essex, UK); E. Pelletier (Univ. du Quebec a Rimouski, Canada).
Polar Biology, Vol 30 No 7, p 925-933, 2007

In December 2000, a field study was initiated on the Kerguelen Archipelago with the objective of determining the long-term effects of a fertilizer addition on the degradation rate and the toxicity of oil residues in soil under severe sub-Antarctic conditions. Of the two sites selected, the organic soil of the first site supported an abundant vegetal cover, while the second site was a vegetation-free mineral soil. Both sites were located in the vicinity of the permanent station of Port-aux-Francais. Two series of five experimental plots (0.75 x 0.75 m) were laid out in each of the study areas. Each plot received 500 mL of diesel fuel or Arabian light crude oil, and some were treated with a bioremediation agent, the slow-release fertilizer Inipol EAP-22®. All plots were sampled on a regular basis over a four-year period. While bioremediation treatments improved the microbial response overall, the addition of fertilizer had greater impact on the mineral soil than on the organic one. Bioremediation treatment improved degradation rates significantly; however, even after four years, the toxicity of oiled soils as determined by Microtox® solid-phase tests persisted despite a significant degradation of alkanes and aromatics. Although a very small amount of contaminant was used in this experiment, four years of bioremediation was not sufficient to return the sites to pristine conditions.

Ferguson, A.S. (Queen's University of Belfast, UK); W.E. Huang; K.A. Lawson; R. Doherty; O. Gibert; K.W. Dickson; A.S. Whiteley; L.A. Kulakov; I.P. Thompson; R.M. Kalin; M.J. Larkin.
Journal of Applied Microbiology, Vol 102 No 5, p 1227-1238, 2007

The authors investigated the distribution of a polymicrobial community of biodegradative bacteria in soil and ground water at a former manufactured gas plant site, as well as in a sequential reactive barrier (SEREBAR) bioremediation process installed to bioremediate polycyclic aromatic hydrocarbons (PAHs) in the ground water. The investigators applied culture-dependent and culture-independent analyses using denaturing gradient gel electrophoresis and polymerase chain reaction for the detection of 16S ribosomal RNA gene and naphthalene dioxygenase genes of samples from across the site and from the SEREBAR process. Naphthalene in the ground water was degraded effectively early in the process, with microbiological analysis indicating a dominant role for Pseudomonas and Comamonas in its degradation. Comparisons made between areas contaminated with PAHs and those not contaminated revealed differences in the microbial community profile, indicating that noncultured bacteria were dominant in mediating naphthalene removal. This work emphasizes the importance of using both traditional and molecular-based tools to determine the microbial ecology of contaminated sites and highlights the role of noncultured bacteria in bioremediation.

Cave, L. (Univ. of New Brunswick, Fredericton, NB, Canada); N. Hartog; T. Al; B. Parker; K.U. Mayer; S. Cogswell. Ground Water Monitoring and Remediation, Vol 27 No 2, p 77-84, 2007

An array of electrical monitoring probes was constructed to monitor a concentrated permanganate solution injected to treat perchloroethene (PCE) contamination in a shallow sandy aquifer. The probes use pairs of stainless steel wires as electrodes for electrical conductivity (EC) measurements and platinum wires as the working electrodes for oxidation-reduction potential (ORP) measurements. Combined EC/ORP probes bundled with multilevel ground-water samplers were installed in boreholes around the injection point. Copper/copper sulfate half-cells, inserted to the depth of the water table, acted as ORP reference electrodes. All electrodes were connected to a central data acquisition system that collected data for a period of 25 days following the injection. Large contrasts in the EC and ORP characteristics of the ground water, compared with the permanganate solution, allowed the subsurface migration of the solution to be tracked using electrical measurements. The electrical data were used to track the arrival times of the permanganate at discrete positions in the aquifer, to guide the timing and selection of locations for water sampling, and for three-dimensional visualization of permanganate distribution during destruction of PCE. Paper at http://www.nielshartog.nl/articles/lcave_GWMR-2007.pdf

Oh, B.-T. (Hallym Univ., South Korea); J.-Y. Lee (Univ. of Seoul); J. Yoon (Seoul National Univ.).
Environmental Geochemistry and Health, Vol 29 No 4, p 331-336, 2007

Batch reactors were used to evaluate the efficacy of waste steel scrap and converter slag to treat mixed contaminants using a synthetic leachate solution. The waste steel scrap was pretreated with an acid-washing process that retained both zero-valent iron and iron oxide. The acid-washed steel scrap removed 95% of trichloroethene (TCE) from the solution within 48 hours. In addition, dehalogenation (chloride production) was greater than 7.5% of the added TCE on a molar basis for 48 hours. The waste steel scrap also removed tetrachloroethene via the dehalogenation process, although to a lesser extent than TCE. Both converter slag and the acid-washed steel scrap removed heavy metals extensively through adsorption. Among salt ions (ammonia, nitrate, and phosphate), phosphate was removed by both waste steel scrap (100% within 8 hours) and converter slag (100% within 20 minutes). Nitrate and ammonia were removed by waste steel scrap (100% within 7 days) and converter slag (up to 50% within 4 days) respectively. These results suggest that permeable reactive barriers enclosing these waste industrial materials might be used effectively to treat mixed contaminants in landfill leachate.

Lee, M., I.S. Paik, W. Do, I. Kim, Y. Lee, and S. Lee, Pukyong National Univ., South Korea.
Environmental Geochemistry and Health, Vol 29 No 4, p 319-329, 2007

Lab-scale soil-washing experiments for arsenic-contaminated stream sediments were performed under various washing conditions to maximize arsenic (As) removal efficiency. Stream sediments were taken from two sites (S1 and S5) along the main stream connected to an abandoned mine. Division of each site sediment by particle size (≥0.35 and <0.35 mm in diameter) yielded four sediments to use in the experiments. Soil washing at varied pH conditions suggested that As removal efficiency is very high in both strongly acidic and basic solutions (pH 1 and 13), regardless of sediment type. Removal efficiencies for fine sediments from S1 and S5 were >95% after 1 h of washing with 0.2 M citric acid. A mixture of 0.2 M citric acid and 0.1 M potassium phosphate increased the As removal efficiency to 100%. Recycling the washing solution maintained As removal efficiency at a level greater than 70%, even after eight recycling events. The experiments revealed the potential utility of soil washing for the remediation of As-contaminated stream sediments around abandoned mines. Paper at http://www.humansphere.net/erp/erpmenus/professor_thesis/upLoadFiles/egh
_2007.pdf

McBeth, J.M., G. Lear, J.R. Lloyd, and F.R. Livens (Univ. of Manchester, Manchester, UK); K. Morris and I.T. Burke (Univ. of Leeds, Leeds, UK).
Geomicrobiology Journal, Vol 24 Nos 3-4, p 189-197, 2007

In a study of the biogeochemical behavior of technetium (Tc) in sediments from a DOE facility, microcosm experiments with trace levels of ⁹⁹Tc(VII) were used to examine Tc reduction and reoxidation. Efficient removal of 0.5 µM Tc(VII) from solution was seen under Fe(III)-reducing conditions and was attributed to a lower-valence insoluble form of the radionuclide. Molecular and cultivation-dependent analysis confirmed the presence of known Fe(III)-reducing bacteria (Geothrix and Geobacter species) in these sediments. Spectroscopic analysis of analogous microcosm experiments, challenged with higher (550 µM) concentrations of Tc(VII), confirmed the presence of reduced insoluble Tc(IV) as hydrous TcO² in the Fe(II)-bearing sediments. Reoxidation experiments of pre-reduced microcosms challenged with 0.5 µM ⁹⁹Tc showed very limited (<3 %) remobilization of the reduced ⁹⁹Tc with 100 mM nitrate but significant (~80%) remobilization of ⁹⁹Tc under air reoxidation conditions. Fe(II) oxidation was significant in all oxidation treatments. Analyses of Fe(II)-bearing sediments challenged with higher (550 µM) concentrations of Tc(VII) and then reoxidized with 100 mM nitrate contained both Tc(IV) and Tc(VII) immobile phases. These results suggest that under anaerobic oxidation conditions, Tc(IV) will not remobilize rapidly, even in the presence of high concentrations of nitrate.

Interstate Technology & Regulatory Council (ITRC), Bioremediation of DNAPLs Team.
Report No: BioDNAPL-3, 138 pp, June 2008

The objective of this publication is to provide a systematic understanding of the technical and related regulatory considerations for in situ bioremediation (ISB) of chlorinated ethene dense nonaqueous-phase liquid (DNAPL) source zones. The document provides information related to site characterization requirements, treatment system application and design criteria, process monitoring, and process optimization. A DNAPL source zone in the saturated subsurface can act as a reservoir that sustains a contaminant plume in ground water. ISB involves stimulating the activity of microorganisms already present in the subsurface (biostimulation) to degrade the dissolved contaminants, and in some cases, adding selected organisms (bioaugmentation). ISB of DNAPL source zones occurs under anaerobic conditions via enhanced reductive dechlorination. This technology has two main components: (1) enhanced dissolution and/or desorption of nonaqueous- and/or sorbed-phase contaminant, and (2) mass biological degradation to nonchlorinated, nontoxic end products. The ability of ISB technology to enhance the dissolution and desorption of nonaqueous-phase contaminants to the aqueous phase, where they can be degraded by the microbial population effectively, depends on the spatial distribution of DNAPL mass in the subsurface (e.g., pool/ganglia ratio) and the ability to deliver amendments throughout this architecture. ISB implementation can result in faster remediation compared to traditional technologies that are limited by the NAPL dissolution rate (e.g., ground-water extraction). Because of its significant impact on the remediation timeframe, enhancement of the NAPL dissolution rate and increasing mass flux are fundamental to the implementation of ISB in a DNAPL source zone. Report at http://www.itrcweb.org/Documents/bioDNPL_Docs/BioDNAPL3.pdf

Vroblesky, Don A., U.S. Geological Survery.
U.S. Geological Survey Scientific Investigations Report 2008-5088, 59 pp, 2008

Analysis of the volatile organic compound (VOC) content of tree cores is an inexpensive, rapid, simple approach to examining the distribution of subsurface VOC contaminants. The method has been shown to detect several volatile petroleum hydrocarbons and chlorinated aliphatic compounds associated with vapor intrusion and ground-water contamination. Tree cores approximately 3 inches in length are obtained by using an increment borer. The cores are placed in vials and sealed. After a period of equilibration, the cores can be analyzed by headspace analysis gas chromatography. Because tree roots are exposed to VOC contamination in the unsaturated zone or shallow ground water, the VOC concentrations in the tree cores are an indication of the presence of VOC contamination in the subsurface. Tree coring thus can be used to detect and map subsurface VOCs. For comparison of tree-core data at a particular site, it is important to maintain consistent methods for all aspects of tree-core collection, handling, and analysis. Numerous factors can affect the VOC concentrations in tree cores: the type of VOC, tree species, rooting depth, ground-water chemistry, depth to the contaminated horizon, concentration differences around the trunk related to variations in the distribution of subsurface VOCs, concentration differences with depth of coring related to volatilization loss through the bark (and possibly other unknown factors), dilution by rain, seasonal influences, sorption, vapor-exchange rates, and within-tree VOC degradation. Report at http://pubs.usgs.gov/sir/2008/5088/

U.S. EPA, Office of Solid Waste, 115 pp, Mar 2008

Shortly after releasing its 2002 draft guidance on vapor intrusion, U.S. EPA initiated efforts to improve the 2002 vapor intrusion database by adding sites and site-related information for a broader cross-section of the country. EPA's vapor intrusion database currently contains indoor air measurements of volatile organic compounds (VOCs) paired with ground-water, soil gas, subslab, or crawlspace measurements for 913 buildings at 41 sites in 15 states. A substantial number of the buildings have multiple paired measurements (e.g., several chemicals reported for the same sample, multiple sampling events reported for the same building, or several types of subsurface samples paired with an indoor air measurement). As a result, the database contains 2,989 paired measurements, of which 35% are paired ground-water and indoor air measurements, 8% are paired soil gas and indoor air measurements, 53% are paired subslab and indoor air measurements, and 4% are paired crawlspace and indoor air measurements. The building types represented include residential (85%), institutional or commercial (10%), and multi-use (residential and non-residential) buildings (5%). Both chlorinated and petroleum hydrocarbons are included in the database, but petroleum hydrocarbons make up only 3% of the data set. At present, the database does not include other compounds (e.g., semi-volatile organic compounds or mercury) that can introduce hazardous components into indoor air through vapor intrusion. The database provides site-specific information, such as geologic setting, soil type, vapor source type (e.g., ground water, soil, nonaqueous-phase liquids in the unsaturated zone), building foundation type, and the vertical and horizontal distance between the building and vapor source. Currently, the vapor intrusion database consists primarily of chlorinated hydrocarbon data obtained in residential settings. EPA expects to update and expand the types of sites, settings, and chemicals in the database as additional data become available. Draft report at http://iavi.rti.org/OtherDocuments.cfm?PageID=documentDetails&AttachID=3
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Mayer, A.L., A.H. Roy, M. White, and C.G. Maurice (U.S. EPA); L. McKinney (ASC Group, Inc.). Report No: EPA 600-R-08-061, 202 pp [main report plus appendices], May 2008

Land use change in EPA's Region 5 (Illinois, Indiana, Michigan, Minnesota, Ohio, and Wisconsin) is occurring rapidly, particularly with the loss of agricultural land and gain in forest and urbanized land use. The risk of losing habitats and ecosystems that are critical to the health of the region is high; however, identifying high-quality, critical habitats remains a challenge. To address this issue, EPA researchers developed a spatially explicit, geographic information system-based model: the Critical Ecosystem Assessment Model (CrEAM). The model was used to generate a relative ecological significance score for each undeveloped 300-meter-by-300-meter cell within EPA Region 5. This report details protocols that were developed to gather field data to verify the CrEAM-generated score independently and quantitatively. The protocols prescribe data collection that captures measures of diversity, rarity, and persistence for forested, nonforested, and wetland ecosystems. For each cell, data are collected in a four-hour time period by a team of four people. Data collected using the protocols in field trials in 2005 and 2006 did not match well with the corresponding CrEAM scores; however, the protocol data did reflect qualitative site assessments conducted by professional ecologists, particularly with respect to the plant communities. The protocols were straightforward to implement in the field and may be useful for applications beyond this project. The main report is accompanied by separate appendices for additional project information: forested terrestrial protocol and datasheets, nonforested terrestrial protocol and datasheets, wetlands protocol and datasheets, and the quality assurance project plan. Report and appendices at http://www.epa.gov/nrmrl/pubs/600r08061/600r08061.htm

U.S. EPA, Office of Air Quality Planning and Standards, 523 pp, May 2008

This workshop was held April 1-3, 2008, under the sponsorship of EPA's Office of Air Quality Planning and Standards, Office of Research and Development, and Office of Solid Waste and Emergency Response. The attendees gathered to discuss remote sensing developments that have occurred since the first workshop, which was held in 2006. The presentations summarized the capabilities of open path technologies and related them to estimation methods now in use, explored current applications of open path technologies, and discussed ways and means for expanding the use of these technologies in evaluating and reducing fugitive emissions. A variety of technologies and applications were covered:
     •       surveys taken using solar occultation flux and differential absorption light (DIAL) detection and ranging systems in the area of Houston, Texas;
     •       monitoring for pipeline gas leaks with an aircraft-mounted DIAL system;
     •       the results of an ongoing two-year continuous fenceline Fourier transform infrared spectroscopy (FTIR) activity at a petrochemical plant;
     •       the use of vertical radial plume mapping (VRPM) to measure landfill fugitive gas emissions and mercury emissions from a chlor-alkali plant;
     •       a fully automated VRPM tunable diode laser absorption spectroscopy system for continuous monitoring of lagoons at consolidated animal feeding operations;
     •       the use of FTIR fenceline monitoring at manufactured gas plant cleanups; and
     •       a research update on the development of equipment that does not require cryogenic cooling to detect in the mid- to far-infrared spectrum.
Also discussed were the implications for facility monitoring as these cutting edge tools become more commonplace, as well as how to promote their use to reduce overall emissions. The workshop resulted in suggestions and recommendations for future actions to be taken by the various entities represented at the meeting. Available at http://www.epa.gov/ttn/chief/efpac/workshops/remotesens08.html