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The application of XPS to the study of MIC

Description: The biotic and abiotic factors that contribute to Microbiologically Influenced Corrosion (MIC) involve the transformation of chemical species at a metal surface. X-ray Photoelectron Spectroscopy (XPS) is utilized in conjunction with conventional microbiological and Quantitative Chemical Analytical techniques to better understand the effect of environmental conditions on microbial behavior as well as the ability of bacteria to alter local environmental conditions. Specifically, the interaction of Fe, Cr, Ni, Mo ions with Desulfovibrio sp. under anoxic conditions were studied. This is the first phase of a systematic study of microbial activity and the effects of alloy elements and thermo-mechanical treatments on the MIC resistance of stainless steels.
Date: January 1, 1992
Creator: Kearns, J. R.; Clayton, C. R.; Halada, G. P.; Gillow, J. B. & Francis, A. J.
Partner: UNT Libraries Government Documents Department

Effects of microbial processes on gas generation under expected WIPP repository conditions: Annual report through 1992

Description: Microbial processes involved in gas generation from degradation of the organic constituents of transuranic waste under conditions expected at the Waste Isolation Pilot Plant (WIPP) repository are being investigated at Brookhaven National Laboratory. These laboratory studies are part of the Sandia National Laboratories -- WIPP Gas Generation Program. Gas generation due to microbial degradation of representative cellulosic waste was investigated in short-term (< 6 months) and long-term (> 6 months) experiments by incubating representative paper (filter paper, paper towels, and tissue) in WIPP brine under initially aerobic (air) and anaerobic (nitrogen) conditions. Samples from the WIPP surficial environment and underground workings harbor gas-producing halophilic microorganisms, the activities of which were studied in short-term experiments. The microorganisms metabolized a variety of organic compounds including cellulose under aerobic, anaerobic, and denitrifying conditions. In long-term experiments, the effects of added nutrients (trace amounts of ammonium nitrate, phosphate, and yeast extract), no nutrients, and nutrients plus excess nitrate on gas production from cellulose degradation.
Date: September 1, 1993
Creator: Francis, A. J. & Gillow, J. B.
Partner: UNT Libraries Government Documents Department

West Valley low-level radioactive waste site revisited: Microbiological analysis of leachates

Description: The abundance and types of microorganisms in leachate samples from the West Valley low-level radioactive waste disposal site were enumerated. This study was undertaken in support of the study conducted by Ecology and Environment, Inc., to assess the extent of radioactive gas emissions from the site. Total aerobic and anaerobic bacteria were enumerated as colony forming units (CFU) by dilution agar plate technique, and denitrifiers, sulfate-reducers and methanogens by the most probable number technique (MPN). Of the three trenches 3, 9, and 11 sampled, trench 11 contained the most number of organisms in the leachate. Concentrations of carbon-14 and tritium were highest in trench 11 leachate. Populations of aerobes and anaerobes in trench 9 leachate were one order of magnitude less than in trench 11 leachate while the methanogens were three orders of magnitude greater than in trench 11 leachate. The methane content from trench 9 was high due to the presence of a large number of methanogens; the gas in this trench also contained the most radioactivity. Trench 3 leachate contained the least number of microorganisms. Comparison of microbial populations in leachates sampled from trenches 3 and 9 during October 1978 and 1989 showed differences in the total number of microbial types. Variations in populations of the different types of organisms in the leachate reflect the changing nutrient conditions in the trenches. 14 refs., 3 figs., 4 tabs.
Date: October 1, 1990
Creator: Gillow, J.B. & Francis, A.J.
Partner: UNT Libraries Government Documents Department

The application of XPS to the study of MIC

Description: The biotic and abiotic factors that contribute to Microbiologically Influenced Corrosion (MIC) involve the transformation of chemical species at a metal surface. X-ray Photoelectron Spectroscopy (XPS) is utilized in conjunction with conventional microbiological and Quantitative Chemical Analytical techniques to better understand the effect of environmental conditions on microbial behavior as well as the ability of bacteria to alter local environmental conditions. Specifically, the interaction of Fe, Cr, Ni, Mo ions with Desulfovibrio sp. under anoxic conditions were studied. This is the first phase of a systematic study of microbial activity and the effects of alloy elements and thermo-mechanical treatments on the MIC resistance of stainless steels.
Date: January 1, 1992
Creator: Kearns, J.R. (Allegheny Ludlum Corp., Brackenridge, PA (United States). Technical Center); Clayton, C.R.; Halada, G.P. (State Univ. of New York, Stony Brook, NY (United States). Dept. of Materials Science); Gillow, J.B. & Francis, A.J. (Brookhaven National Lab., Upton, NY (United States))
Partner: UNT Libraries Government Documents Department

Microbial transformation of uranium in wastes

Description: Contamination of soils, water, and sediments by radionuclides and toxic metals from the disposal of uranium processing wastes is a major national concern. Although much is known about the physico- chemical aspects of U, we have little information on the effects of aerobic and anaerobic microbial activities on the mobilization or immobilization of U and other toxic metals in mixed wastes. In order to understand the mechanisms of microbial transformations of uranium, we examined a contaminated pond sediment and a sludge sample from the uranium processing facility at Y-12 Plant, Oak Ridge, TN. The uranium concentration in the sediment and sludge samples was 923 and 3080 ug/g dry wt, respectively. In addition to U, the sediment and sludge samples contained high levels of toxic metals such as Cd, Cr, Cu, Hg, Pb, Ni, and Zn. The association of uranium with the various mineral fractions of the sediment and sludge was determined by selective chemical extraction techniques. Uranium was associated to varying degrees with the exchangeable carbonate, iron oxide, organic, and inert fractions in both samples. Initial results in samples amended with carbon and nitrogen indicate immobilization of U due to enhanced indigenous microbial activity under anaerobic conditions. 23 refs., 4 figs., 5 tabs.
Date: January 1, 1989
Creator: Francis, A.J.; Dodge, C.J.; Gillow, J.B.; Cline, J.E. (Brookhaven National Lab., Upton, NY (USA) & Oak Ridge Y-12 Plant, TN (USA))
Partner: UNT Libraries Government Documents Department

BIOGEOCHEMICAL CYCLING AND ENVIRONMENTAL STABILITY OF PLUTONIUM RELEVANT TO LONG-TERM STEWARDSHIP OF DOE SITES

Description: Pu is generally considered to be relatively immobile in the terrestrial environment, with the exception of transport via airborne and erosion mechanisms. More recently the transport of colloidal forms of Pu is being studied as a mobilization pathway from subsurface contaminated soils and sediments. The overall objective of this research is to understand the biogeochemical cycling of Pu in environments of interest to long-term DOE stewardship issues. Microbial processes are central to the immobilization of Pu species, through the metabolism of organically complexed Pu species and Pu associated with extracellular carrier phases and the creation of environments favorable for retardation of Pu transport.
Date: June 1, 2006
Creator: Francis, A. J.; Gillow, J. B. & Dodge, C. J.
Partner: UNT Libraries Government Documents Department

Microbial Gas Generation Under Expected Waste Isolation Pilot Plant Repository Conditions: Final Report

Description: Gas generation from the microbial degradation of the organic constituents of transuranic (TRU) waste under conditions expected in the Waste Isolation Pilot Plant (WIPP) was investigated. The biodegradation of mixed cellulosic materials and electron-beam irradiated plastic and rubber materials (polyethylene, polyvinylchloride, hypalon, leaded hypalon, and neoprene) was examined. We evaluated the effects of environmental variables such as initial atmosphere (air or nitrogen), water content (humid ({approx}70% relative humidity, RH) and brine inundated), and nutrient amendments (nitogen phosphate, yeast extract, and excess nitrate) on microbial gas generation. Total gas production was determined by pressure measurement and carbon dioxide (CO{sub 2}) and methane (CH{sub 4}) were analyzed by gas chromatography; cellulose degradation products in solution were analyzed by high-performance liquid chromatography. Microbial populations in the samples were determined by direct microscopy and molecular analysis. The results of this work are summarized.
Date: July 1, 2011
Creator: Gillow, J. B. & Francis, A.
Partner: UNT Libraries Government Documents Department

Actinide Biocolloid Formation in Brine by Halophilic Bacteria

Description: We examined the ability of a halophilic bacterium (WFP 1A) isolated from the Waste Isolation Pilot Plant (WIPP) site to accumulate uranium in order to determine the potential for biocolloid facilitated actinide transport. The bacterial cell Surface functional groups involved in the complexation of the actinide were determined by titration. Uranium, added as uranyl nitrate, was removed from solution at pH 5 by cells but at pH 7 and 9 very little uranium was removed due to its limited volubility. Although present as soluble species, uranyl citrate at pH 5, 7, and 9, and uranyl carbonate at pH 9 were not removed by the bacterium because they were not bioavailable due to their neutral or negative charge. Addition of uranyl EDTA to brine at pH 5, 7, and 9 resulted in the immediate precipitation of U. Transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) analysis revealed that uranium was not only associated with the cell surface but also accumulated intracellulary as uranium-enriched granules. Extended X-ray absorption fine structure (EXAFS) analysis, of the bacterial cells indicated the bulk sample contained more than one uranium phase. Nevertheless these results show the potential for the formation of actinide bearing bacterial biocolloids that are strictly regulated by the speciation and bioavailability of the actinide.
Date: July 28, 1999
Creator: Gillow, J.B.; Francis, A.J.; Dodge, C.J.; Harris, R.; Beveridge, T.J.; Brady, P.V. et al.
Partner: UNT Libraries Government Documents Department

A Scanning Auger Microprobe analysis of corrosion products associated with sulfate reducing bacteria

Description: A Scanning Auger Microprobe analysis was performed on the corrosion products of an austenitic AISI type 304 SS after a potentiostatic polarization of one volt for ten minutes in a modified Postgate`s C media containing sulfate reducing bacteria. The corrosion products were characterized and mapped in local regions where pitting was observed. A critical evaluation of the applicability of this technique for the examination of microbially influenced corrosion (MIC) is presented.
Date: March 1, 1995
Creator: Sadowski, R.A.; Chen, G.; Clayton, C.R.; Kearns, J.R.; Gillow, J.B. & Francis, A.J.
Partner: UNT Libraries Government Documents Department

Mucrobial Stabilization of Plutonium in the Subsurface Environment

Description: This report outlines the results of work performed at the Colorado School of Mines, Brookhaven National Laboratory and Texas A and M University during the second reporting phase of this project. The sub-projects focused on this year include: (1) Biotransformation of Pu-contaminated soil; (2) Environmental colloids at the Rocky Flats Environmental Technology Site; (3) Production, isolation and characterization of EPS (exopolymeric substances, or exopolysaccharides); (4) Colloid trapping; (5) Determination of stability constants of complexes of Pu(IV) with organic ligands; and (6) The role of bacterial EPS in the transport of Pu through saturated porous media.
Date: June 1, 2004
Creator: Honeyman, B. J.; Francis, A. J.; Dodge, C. J.; Gillow, J. B. & Santschi, P. H.
Partner: UNT Libraries Government Documents Department

Mechanisms of Radionuclide-Hyroxycarboxylic Acid Interactions for Decontamination of Metallic Surfaces

Description: Is this EMSP program we investigated the key fundamental issues involved in the use of simple and safe methods for the removal of radioactive contamination from equipment and facilities using hydroxycarboxylic acids. Specifically, we investigate (i) the association of uranium with various iron oxides commonly formed on corroding plain carbon steel surfaces, (ii) the association of uranium with corroding metal coupons under a variety of conditions, and (iii) the decontamination of the uranium contaminated metal coupons by citric acid or citric acid formulations containing oxalic acid and hydrogen peroxide.
Date: April 24, 2002
Creator: Francis, A. J.; Dodge, C. J.; Gillow, J. B.; Halada, G. P. & Clayton, C. R.
Partner: UNT Libraries Government Documents Department

BNL Citric Acid Technology: Pilot Scale Demonstration

Description: The objective of this project is to remove toxic metals such as lead and cadmium from incinerator ash using the Citric Acid Process developed at Brookhaven National Laboratory. In this process toxic metals in bottom ash from the incineration of municipal solid waste were first extracted with citric acid followed by biodegradation of the citric acid-metal extract by the bacterium Pseudomonas fluorescens for metals recovery. The ash contained the following metals: Al, As, Ba, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Se, Sr, Ti, and Zn. Optimization of the Citric Acid Process parameters which included citric acid molarity, contact time, the impact of mixing aggressiveness during extraction and pretreatment showed lead and cadmium removal from incinerator ash of >90%. Seeding the treated ash with P. fluorescens resulted in the removal of residual citric acid and biostabilization of any leachable lead, thus allowing it to pass EPA?s Toxicity Characteristic Leaching Procedure. Biodegradation of the citric acid extract removed >99% of the lead from the extract as well as other metals such as Al, Ca, Cu, Fe, Mg, Mn, Ti, and Zn. Speciation of the bioprecipitated lead by Extended X-ray Absorption Fine Structure at the National Synchrotron Light Source showed that the lead is predominantly associated with the phosphate and carboxyl functional groups in a stable form. Citric acid was completely recovered (>99%) from the extract by sulfide precipitation technique and the extraction efficiency of recovered citric acid is similar to that of the fresh citric acid. Recycling of the citric acid should result in considerable savings in the overall treatment cost. We have shown the potential application of this technology to remove and recover the metal contaminants from incinerator ash as well as from other heavy metal bearing wastes (i.e., electric arc furnace dust from steel industry) or soils. ...
Date: September 24, 1999
Creator: FRANCIS, A J; DODGE,; J, C; GILLOW, J B & FORRESTER, K E
Partner: UNT Libraries Government Documents Department

Enumeration of Microbial Populations in Radioactive Environments by Epifluorescence Microscopy

Description: Epifluorescence microscopy was utilized to enumerate halophilic bacterial populations in two studies involving inoculated, actual radioactive waste/brine mixtures and pure brine solutions. The studies include an initial set of experiments designed to elucidate potential transformations of actinide-containing wastes under salt-repository conditions, including microbially mediated changes. The first study included periodic enumeration of bacterial populations of a mixed inoculum initially added to a collection of test containers. The contents of the test containers are the different types of actual radioactive waste that could potentially be stored in nuclear waste repositories in a salt environment. The transuranic waste was generated from materials used in actinide laboratory research. The results show that cell numbers decreased with time. Sorption of the bacteria to solid surfaces in the test system is discussed as a possible mechanism for the decrease in cell numbers. The second study was designed to determine radiological and/or chemical effects of {sup 239}Pu, {sup 243}Am, {sup 237}Np, {sup 232}Th and {sup 238}U on the growth of pure and mixed anaerobic, denitrifying bacterial cultures in brine media. Pu, Am, and Np isotopes at concentrations of &lt;=1 x 10{sup {minus}5}M, &lt;=5 x 10{sup {minus}6}M and &lt;=5 x 10{sup {minus}4}M respectively, and Th and U isotopes &lt;=4 x 10{sup {minus}3}M were tested in these media. The results indicate that high actinide concentration affected both the bacterial growth rate and morphology. However, relatively minor effects from Am were observed at all tested concentrations with the pure culture.
Date: December 2, 1996
Creator: Pansoy-Hjelvik, M.E.A.; Strietelmeierr, B.A.; Paffett, M.T.; Kitten, S.M.; Leonard, P.A.; Dunn, M. et al.
Partner: UNT Libraries Government Documents Department

Interaction of Plutonium with Bacteria in the Repository Environment

Description: Microorganisms in the nuclear waste repository environment may interact with plutonium through (1) sorption, (2) intracellular accumulation, and (3) transformation speciation. These interactions may retard or enhance the mobility of Pu by precipitation reactions, biocolloid formation, or production of more soluble species. Current and planned radioactive waste repository environments, such as deep subsurface halite and granite formations, are considered extreme relative to life processes in the near-surface terrestrial environment. There is a paucity of information on the biotransformation of radionuclides by microorganisms present in such extreme environments. In order to gain a better understanding of the interaction of plutonium with microorganisms present in the waste repository sites we investigated a pure culture (Halomonas sp.) and a mixed culture of bacteria (Haloarcula sinaiiensis, Marinobacter hydrocarbonoclasticus, Altermonas sp., and a {gamma}-proteobacterium) isolated from the Waste Isolation Pilot Plant (WIPP) site and an Acetobacterium sp. from alkaline groundwater at the Grimsel Test Site in Switzerland.
Date: July 1, 2000
Creator: Gillow, J. B.; Francis, A. J.; Lucero, D. A. & Papenguth, H. W.
Partner: UNT Libraries Government Documents Department

ACTINIDE BIOCOLLOID FORMATION IN BRINE BY HALOPHILIC BACTERIA

Description: The authors examined the ability of a halophilic bacterium (WIPP 1A) isolated from the Waste Isolation Pilot Plant (WIPP) site to accumulate uranium in order to determine the potential for biocolloid facilitated actinide transport. The bacterial cell surface functional groups involved in the complexation of the actinide were determined by titration. Uranium, added as uranyl nitrate, was removed from solution at pH 5 by cells but at pH 7 and 9 very little uranium was removed due to its limited solubility. Although present as soluble species, uranyl citrate at pH 5, 7, and 9, and uranyl carbonate at pH 9 were not removed by the bacterium because they were not bioavailable due to their neutral or negative charge. Addition of uranyl EDTA to brine at pH 5, 7, and 9 resulted in the immediate precipitation of U. Transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) analysis revealed that uranium was not only associated with the cell surface but also accumulated intracellularly as uranium-enriched granules. Extended X-ray absorption fine structure (EXAFS) analysis of the bacterial cells indicated the bulk sample contained more than one uranium phase. Nevertheless these results show the potential for the formation of actinide bearing bacterial biocolloids that are strictly regulated by the speciation and bioavailability of the actinide.
Date: November 9, 1998
Creator: GILLOW,J.B.; FRANCIS,A.J.; DODGE,C.J.; HARRIS,R.; BEVERIDGE,T.J.; BRADY,P.B. et al.
Partner: UNT Libraries Government Documents Department

Laboratory evaluation of colloidal actinide transport at the Waste Isolation Pilot Plant (WIPP): 1. crushed-dolomite column flow...

Description: Colloid-facilitated transport of Pu, Am, U, Th, and Np has been recognized as a potentially important phenomenon affecting the performance of the Waste Isolation Pilot Plant (WIPP) facility being developed for safe disposal of transuranic radioactive waste. In a human intrusion scenario, actinide-bearing colloidal particles may be released from the repository and be transported by brines (approximately 0.8 to 3 molal ionic strength) through the Culebra, a thin fractured microcrystalline (mean grain size 2 micrometers) dolomite aquifer overlying the repository. Transport experiments were conducted using sieved, uniformly packed crushed Culebra rock or nonporous dolomite cleavage rhombohedra. Experiments with mineral fragments and fixed and live WIPP-relevant bacteria cultures showed significant levels of retardation due to physical filtration effects. Humic substances were not attenuated by the Culebra dolomite. Comparison of elution curves of latex microspheres in columns prepared with microcrystalline rock and nonporous rock showed minimal effect of Culebra micropores on colloid transport. These data form part of the basis to parameterize numerical codes being used to evaluate the performance of the WIPP.
Date: December 31, 1996
Creator: Yelton, W.G.; Behl, Y.K.; Kelly, J.W.; Dunn, M.; Gillow, J.B.; Francis, A.J. et al.
Partner: UNT Libraries Government Documents Department

Actinide biocolloid formation in brine by halophilic bacteria

Description: The authors examined the ability of a halophilic bacterium (WIPP 1A) isolated from the Waste Isolation Pilot Plant (WIPP) site to accumulate uranium in order to determine the potential for biocolloid facilitated actinide transport. The bacterial cell surface functional groups involved in the complexation of the actinide were determined by titration. Uranium, added as uranyl nitrate, was removed from solution at pH 5 by cells but at pH 7 and 9 very little uranium was removed due to its limited solubility. Although present as soluble species, uranyl citrate at pH 5, 7, and 9, and uranyl carbonate at pH 9 were not removed by the bacterium because they were not bioavailable due to their neutral or negative charge. Addition of uranyl EDTA to brine at pH 5, 7, and 9 resulted in the immediate precipitation of U. Transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) analysis revealed that uranium was not only associated with the cell surface but also accumulated intracellularly as uranium-enriched granules. Extended X-ray absorption fine structure (EXAFS) analysis of the bacterial cells indicated the bulk sample contained more than one uranium phase. Nevertheless these results show the potential for the formation of actinide bearing bacterial biocolloids that are strictly regulated by the speciation and bioavailability of the actinide.
Date: December 31, 1998
Creator: Gillow, J.B.; Francis, A.J.; Dodge, C.J.; Harris, R.; Beveridge, T.J.; Brady, P.V. et al.
Partner: UNT Libraries Government Documents Department

Role of Microbes as Biocolloids in the Transport of Actinides from a Deep Underground Radioactive Waste Repository

Description: We investigated the interaction of dissolved actinides Th, U, Np Zgpu, and Am, with a pure and a mixed culture of halophilic bactezia isolated from the Waste Isolation H.Iot Plant repository under anaerobic conditions to evaluate their potentiaI transport as biocolloids from the waste site. The sizes of the bacterial cells studied ranged from ().54 x 0.48 pm to 7.7 x 0.67pm Using sequential mimofiltration, we determined the ~~ation of actinides with fi-ee-living (mobile) bacterial cells suspended in a fluid medium containing. NaCl or M=W12 brine, at various phaes of their growth cycIes. The number of suspended kcteria rangy-d born 106 to 109 cells ml-*. Tine amount of actinide associatd with the wspend~ cell fraction (cakzdated & mol cell-*) was very Iow: Th, 10-*2; U, 10-1s - 10-lS; - ~ Np, 1o-15- 10-19; Pu, 10-ls -10-21 ; and h, 10-1* - 10-*9 ; and it varied with the bacteihl - CUIture studied. l%e differe&es in the asswiation are amibuted to the extent of bioamxmdation and biosorption by the bacteria pH, the compo&on of the brine, and the speziation and bioavaiIability of the actinides.
Date: December 17, 1998
Creator: Dodge, C.J.; Dunn, M.; Francis, A.J.; Gillow, J.B.; Mantione, K.; Pansoy-Hjelvik, M.E. et al.
Partner: UNT Libraries Government Documents Department

Enumeration and characterization of microorganisms associated with the uranium ore deposit at Cigar Lake, Canada; Informal report

Description: The high-grade uranium deposit at Cigar Lake, Canada, is being investigated as a natural analog for the disposal of nuclear fuel waste. Geochemical aspects of the site have been studied in detail, but the microbial ecology has not been fully investigated. Microbial populations in an ore sample and in groundwater samples from the vicinity of the ore zone were examined to determine their effect on uranium mobility. Counts of the total number of bacteria and of respiring bacteria were obtained by direct microscopy, and the viable aerobic and anaerobic bacteria were assessed as colony forming units (CFUs) by the dilution plating technique. In addition, the population distribution of denitrifiers, fermenters, iron- and sulfur-oxidizers, iron- and sulfate-reducers, and methanogens was determined by the most probable number (MPN) technique.
Date: March 1, 1994
Creator: Francis, A.J.; Joshi-Tope, G.; Gillow, J.B. & Dodge, C.J.
Partner: UNT Libraries Government Documents Department