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Characterization Activities Conducted at the 183-DR Site in Support of an In Situ Gaseous Reduction Demonstration

Description: In Situ Gaseous Reduction (ISGR) is a technology developed by DOE for the remediation of soil waste sites contaminated with hexavalent chromium. This document presents information associated with characterization activities conducted at the 183-DR site at Hanford, which is associated with a significant groundwater contaminant plume and was formerly a water treatment facility that utilized chromate as a corrosion inhibitor. Geotechnical and chemical data were collected during the excavation of trenches and the drilling of two vadose zone boreholes to support a possible ISGR demonstration at 183-DR. Although elevated total chromium and trace levels of hexavalent chromium were identified from one of the trenches and one of the boreholes, it appears that the boreholes missed the vadose zone contaminant source responsible for the chromium groundwater plume located downgradient of the 183-DR site. Recommendations are provided, however, for future work at 183-DR that may serve to identify the source for the groundwater plume and possibly provide an opportunity for an ISGR demonstration.
Date: March 30, 2001
Creator: Thornton, Edward C.; Gilmore, Tyler J.; Olsen, Khris B.; Schalla, Ronald & Cantrell, Kirk J.
Partner: UNT Libraries Government Documents Department

Investigation of Hexavalent Chromium Flux to Groundwater at the 100-C-7:1 Excavation Site

Description: Deep excavation of soil has been conducted at the 100-C-7 and 100-C-7:1 waste sites within the 100-BC Operable Unit at the Department of Energy (DOE) Hanford Site to remove hexavalent chromium (Cr(VI)) contamination with the excavations reaching to near the water table. Soil sampling showed that Cr(VI) contamination was still present at the bottom of the 100-C-7:1 excavation. In addition, Cr(VI) concentrations in a downgradient monitoring well have shown a transient spike of increased Cr(VI) concentration following initiation of excavation. Potentially, the increased Cr(VI) concentrations in the downgradient monitoring well are due to Cr(VI) from the excavation site. However, data were needed to evaluate this possibility and to quantify the overall impact of the 100-C-7:1 excavation site on groundwater. Data collected from a network of aquifer tubes installed across the floor of the 100-C-7:1 excavation and from temporary wells installed at the bottom of the entrance ramp to the excavation were used to evaluate Cr(VI) releases into the aquifer and to estimate local-scale hydraulic properties and groundwater flow velocity.
Date: November 16, 2012
Creator: Truex, Michael J.; Vermeul, Vincent R.; Fritz, Brad G.; Mackley, Rob D.; Horner, Jacob A.; Johnson, Christian D. et al.
Partner: UNT Libraries Government Documents Department

Effect of Cr addition on γ-γ' cobalt-based Co-Mo-Al-Ta class of superalloys: a combined experimental and computational study

Description: This article deals with effect of Cr addition (10 at.%) on the partitioning behavior and the consequent effect on mechanical properties for tungsten-free γ-γ' cobalt-based superalloys with base alloy compositions of Co–30Ni–10Al–5Mo–2Ta (2Ta) and Co–30Ni–10Al–5Mo–2Ta–2Ti (2Ta2Ti).
Date: June 12, 2017
Creator: Nithin, B.; Samanta, A.; Makineni, S. K.; Alam, Talukder; Pandey, P.; Singh, Abhishek K. et al.
Partner: UNT College of Engineering

Sponge Chromium

Description: From Introduction: "There follows discussion of the reduction processes suitable for preparing sponge chromium from the chlorides, and finally the question of special methods required to insure the production of a high-purity product is investigated. This order is a natural and chronological one as well as being suited to the needs of presenting an analytic picture of the experimental work and its results and proposals engendered."
Date: 1942
Creator: Maier, C. G.
Partner: UNT Libraries Government Documents Department

Hydrolytic polymerization of chromium (III) hydroxides in the aquatic environment

Description: Products of hydrolytic polymerization of Cr(III) hydroxide were investigated in Milli-Q water and in natural water matrices. Products were first fractionated on Sephadex column using eluents of increasing strength. Ion chromatography (IC) with UV detection at 436 nm was then used to separate the ionic species.
Date: December 1991
Creator: Mbamalu, Godwin E.
Partner: UNT Libraries

Hydrogen Peroxide Analysis and Decomposition in Chromate Solutions

Description: Abstract: "A novel procedure employing ion exchange resins was developed to separate chromate ions from hydrogen peroxide, permitting, permitting the subsequent analysis of peroxide to determine its decomposition in sodium chromate solutions. At high pH's, peroxide was absorbed anionically on the ion exchange resins along with chromate. By selecting a resin which would be effective at nearly neutral conditions, chromate was satisfactorily separated from peroxide. It was found that the rate of peroxide decomposition in slightly alkaline sodium chromate solutions was dependent on temperature, pH, aeration, and chromate concentration. No significant effect on decomposition was caused by visible light."
Date: March 17, 1952
Creator: Rynasiewicz, Joseph & Ryan, J. W.
Partner: UNT Libraries Government Documents Department

Properties of Arc-Melted Chromium-Base Alloys

Description: From abstract: "Twelve binary chromium-base alloy systems were screened for hot workability, oxidation resistance, and hot strength using small ore-melted ingots...Experiments with the preparation of large chromium-base alloy ingots showed that cold-mold ore melting was not suitable for preparing ingots containing over about 1 w/o of alloy addition."
Date: July 14, 1958
Creator: Maykuth, Daniel J.; Roberts, John W., Jr. & Jaffee, Robert Isaac
Partner: UNT Libraries Government Documents Department

Kinetics of sintering chromium carbide

Description: Report presenting an investigation of the sintering of chromium carbide under pressure in order to study the kinetics of grain growth and densification during this process. Densification of a sintered chromium carbide compact was accompanied by grain growth and density and grain size seem to be interdependent during this stage of the sintering process.
Date: August 1951
Creator: Lidman, William G. & Hamjian, H. J.
Partner: UNT Libraries Government Documents Department

Differential isotopic fractionation during Cr(VI) reduction by an aquifer-derived bacterium under arobic versus denitrifying conditions

Description: We studied Cr isotopic fractionation during Cr(VI) reduction by Pseudomonas stutzeri strain RCH2. Despite the fact that strain RCH2 reduces Cr(VI) co-metabolically under both aerobic and denitrifying conditions and at similar specific rates, fractionation was markedly different under these two conditions (ε ~2� aerobically and ~0.4� under denitrifying conditions).
Date: February 1, 2012
Creator: Han, R.; Qin, L.; Brown, S. T.; Christensen, J. N. & Beller, H. R.
Partner: UNT Libraries Government Documents Department

Ion Chromatography of Soluble Cr(III) and Cr(VI)

Description: Ion chromatography coupled with a conductivity detector was used to investigate the analysis of Cr(III) and Cr(VI) in aqueous samples. An IC methodology for Cr(III) was developed using a cation column and an eluent containing tartaric acid, ethylenediamine, and acetonitrile at pH 2.9. The detection limit of this method can reach 0.1 ppm level with good precision. Several operational parameters were evaluated during the regular use of the method. Comparison of the IC method with AA method showed good agreement between the two methods. The anion exchange column was used for Cr(VI) determination. The best results were obtained with an eluent containing sodium gluconate, borate buffer, glycerin, and acetonitrile. The retention time for the Cr207 2 - sample was 11 min. and the calibration curve was linear between 1.0 and 100 ppm.
Date: August 1988
Creator: Huang, Julie Shiong-Jiun
Partner: UNT Libraries

Low-Coordinate Chromium Siloxides: The "Box" [Cr(μ-OSitBu3)]4, Distorted Trigonal [(tBu3SiO)3Cr] [Na(benzene)] and [(tBu3SiO)3Cr] [Na(dibenzo-18-c-6)], and Trigonal (tBu3SiO)3Cr

Description: Article discussing low-coordinate chromium siloxides and the "box" [Cr(μ-Cl)(μ-OSiᵗBu₃)]₄, distorted trigonal [(ᵗBu₃SiO)₃Cr][Na(benzene)] and [(ᵗBu₃SiO)₃Cr][Na(dibenzo-18-c-6)], and trigonal (ᵗBu₃SiO)₃Cr.
Date: March 24, 2005
Creator: Sydora, Orson L.; Wolczanski, Peter T.; Lobkovsky, Emil B.; Buda, Corneliu & Cundari, Thomas R., 1964-
Partner: UNT College of Arts and Sciences

Influence of structure on properties of sintered chromium carbide

Description: Report presenting an investigation to study the influence of structural variations on the properties of chromium carbide sintered under pressure. The results show that the room-temperature strength and hardness are influenced by the stages of sintering, which are defined by grain size and by the number, size, location, and shape of pores.
Date: June 1952
Creator: Hamjian, H. J. & Lidman, W. G.
Partner: UNT Libraries Government Documents Department

Description of Work for Drilling at the 183-DR Site in Support of the In Situ Gaseous Reduction Test

Description: In Situ Gaseous Reduction is a technology currently being developed by DOE for the remediation of soil waste sites contaminated with hexavalent chromium. Prior work suggests that a candidate for application of this approach is the 183-DR site at Hanford. However, deep vadose zone drilling is needed to verify the presence of a hexavalent chromium source and to determine the concentration levels and spatial distribution of contamination. This document presents the requirements associated with drilling one to two vadose zone boreholes at the 183-DR site to obtain this information. If hexavalent chromium is determined to be present at levels of at least 10 ppm in the vadose zone in one of the initial boreholes, this hole will be completed for gas injection and six additional gas extraction boreholes will be drilled and completed. This network will be used as a flowcell for performing a gas treatment test at the site.
Date: June 26, 2000
Creator: Thornton, Edward C.; Olsen, Khris B. & Schalla, Ronald
Partner: UNT Libraries Government Documents Department

Sampling Instruction: Investigation of Hexavalent Chromium Flux to Groundwater at the 100-C-7:1 Excavation Site

Description: Several types of data are needed to assess the flux of Cr(VI) from the excavation into the groundwater. As described in this plan, these data include (1) temporal Cr(VI) data in the shallow groundwater beneath the pit; (2) hydrologic data to interpret groundwater flow and contaminant transport; (3) hydraulic gradient data; and (4) as a contingency action if necessary, vertical profiling of Cr(VI) concentrations in the shallow aquifer beyond the depth possible with aquifer tubes.
Date: May 1, 2012
Creator: Truex, Michael J. & Vermeul, Vincent R.
Partner: UNT Libraries Government Documents Department

Spin-density-wave antiferromagnetism of Cr in Fe/Cr(001) superlattices

Description: The antiferromagnetic spin-density-wave (SDW) order of Cr layers in Fe/Cr(001) superlattices was investigated by neutron scattering. For Cr thickness 51-190 {Angstrom}, a transverse SDW is formed for all temperatures below Neel temperature with a single wavevector Q normal to the layers. A coherent magnetic structure forms with the nodes of the SDW near the Fe-Cr interfaces. For thinner Cr layers, the magnetic scattering can be described by commensurate antiferromagnetic order.
Date: October 1, 1996
Creator: Fullerton, E.E.; Bader, S.D. & Robertson, J.L.
Partner: UNT Libraries Government Documents Department

Identification of a Hanford Waste Site for Initial Deployment of the In Situ Gaseous Reduction Approach

Description: In Situ Gaseous Reduction is a technology currently being developed by DOE for the remediation of soil waste sites contaminated with hexavalent chromium. This document presents the results of recent characterization activities undertaken at several of the soil waste sites at Hanford that contain significant levels of hexavalent chromium contamination. The objective of this study is to select a site for initial deployment of the technology at the Hanford Site.
Date: November 28, 2000
Creator: Thornton, Edward C; Cantrell, Kirk J; Faurote, James M; Gilmore, Terrance J; Olsen, Khris B & Schalla, Ronald
Partner: UNT Libraries Government Documents Department

Quantitative Analysis Laboratory Experiment: Bilinear Regression Analysis as a Means to Reduce Matrix Effects in Simultaneous Spectrophotometric Determination of Cr(III) and Co(II)

Description: Article on bilinear regression analysis as a means to reduce matrix effects in simultaneous spectrophotometric determination of Cr(III) and Co(II) and a quantitative analysis laboratory experiment.
Date: July 1, 1998
Creator: Pandey, Siddharth; McHale, Mary E. R.; Coym, Karen S. & Acree, William E. (William Eugene)
Partner: UNT College of Arts and Sciences

Progress Reports - Metallurgical Division: 13. Electrometallurgical Investigations

Description: Report issued by the U.S. Bureau of Mines on the progress made on projects in the Metallurgical Division. Descriptions of progress in the different projects and operations conducted are listed. This report includes tables, graphs, and illustrations.
Date: October 1936
Creator: Koster, J.; Shelton, S. M. & Knickerbocker, R. G.
Partner: UNT Libraries Government Documents Department

High-Temperature Oxidation Resistance of Thin Iron-Chromium-Aluminum Alloy Sheet

Description: Abstract: "The oxidation resistance of thin sheets of iron-28 w/o chromium-2.67 to 10.0 w/o alloys, nominally 0.004, 0.006, 0.008, 0.012, and 0.016 in. thick, was determined by exposure in static air for 100 hr at 2100 and 2300 F. A minimum of 3.67 and 9.37 w/o aluminum was necessary to prevent excessive oxidation of 0.004-in.-thick sheet material at 2100 and 2300 F, respectively. Correspondingly, specimens of lower aluminum content and greater thickness withstood the oxidation attack. Oxidation of iron-chromium-aluminum alloys appeared to be related to the diffusion of aluminum to surfaces of the sheet to form an adherent protective layer of Al2O3."
Date: October 22, 1957
Creator: Jablonowski, Edward J.; Shober, Frederic R. & Dickerson, Ronald F.
Partner: UNT Libraries Government Documents Department