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Thermally conductive cementitious grouts for geothermal heat pumps. Progress report FY 1998

Description: Research commenced in FY 97 to determine the suitability of superplasticized cement-sand grouts for backfilling vertical boreholes used with geothermal heat pump (GHP) systems. The overall objectives were to develop, evaluate and demonstrate cementitious grouts that could reduce the required bore length and improve the performance of GHPs. This report summarizes the accomplishments in FY 98. The developed thermally conductive grout consists of cement, water, a particular grade of silica sand, superplasticizer and a small amount of bentonite. While the primary function of the grout is to facilitate heat transfer between the U-loop and surrounding formation, it is also essential that the grout act as an effective borehole sealant. Two types of permeability (hydraulic conductivity) tests was conducted to evaluate the sealing performance of the cement-sand grout. Additional properties of the proposed grout that were investigated include bleeding, shrinkage, bond strength, freeze-thaw durability, compressive, flexural and tensile strengths, elastic modulus, Poisson`s ratio and ultrasonic pulse velocity.
Date: November 1, 1998
Creator: Allan, M.L. & Philippacopoulos, A.J.
Partner: UNT Libraries Government Documents Department

Mixed Waste Salt Encapsulation Using Polysiloxane - Final Report

Description: A proof-of-concept experimental study was performed to investigate the use of Orbit Technologies polysiloxane grouting material for encapsulation of U.S. Department of Energy mixed waste salts leading to a final waste form for disposal. Evaporator pond salt residues and other salt-like material contaminated with both radioactive isotopes and hazardous components are ubiquitous in the DOE complex and may exceed 250,000,000 kg of material. Current treatment involves mixing low waste percentages (less than 10% by mass salt) with cement or costly thermal treatment followed by cementation to the ash residue. The proposed technology involves simple mixing of the granular salt material (with relatively high waste loadings-greater than 50%) in a polysiloxane-based system that polymerizes to form a silicon-based polymer material. This study involved a mixing study to determine optimum waste loadings and compressive strengths of the resultant monoliths. Following the mixing study, durability testing was performed on promising waste forms. Leaching studies including the accelerated leach test and the toxicity characteristic leaching procedure were also performed on a high nitrate salt waste form. In addition to this testing, the waste form was examined by scanning electron microscope. Preliminary cost estimates for applying this technology to the DOE complex mixed waste salt problem is also given.
Date: November 1, 1997
Creator: Miller, C.M.; Loomis, G.G. & Prewett, S.W.
Partner: UNT Libraries Government Documents Department

THERMALLY CONDUCTIVE CEMENTITIOUS GROUTS FOR GEOTHERMAL HEAT PUMPS. PROGRESS REPORT BY 1998

Description: Research commenced in FY 97 to determine the suitability of superplasticized cement-sand grouts for backfilling vertical boreholes used with geothermal heat pump (GHP) systems. The overall objectives were to develop, evaluate and demonstrate cementitious grouts that could reduce the required bore length and improve the performance of GHPs. This report summarizes the accomplishments in FY 98.
Date: November 1, 1998
Creator: ALLAN,M.L. & PHILIPPACOPOULOS,A.J.
Partner: UNT Libraries Government Documents Department

CsIX/TRU Grout Feasibility Study

Description: A settlement agreement between the Department of Energy (DOE) and the State of Idaho mandates that liquid waste now stored at the Idaho Nuclear Technology Engineering Center (INTEC - formerly the Idaho Chemical Processing Plant, ICPP) will be calcined by the end of year 2012. This study investigates an alternative treatment of the liquid waste that removes undissolved solids (UDS) by filtration and removes cesium by ion exchange followed by cement-based grouting of the remaining liquid into 55-gal drums. Operations are assumed to be from January 2008 through December 2012. The grouted waste will be contact-handled and will be shipped to the Waste Isolation Pilot Plant (WIPP) in New Mexico for disposal. The small volume of secondary wastes such as the filtered solids and cesium sorbent (resin) would remain in storage at the Idaho National Engineering and Environmental Laboratory for treatment and disposal under another project, with an option to dispose of the filtered solids as a r emote-handled waste at WIPP.
Date: November 1, 1998
Creator: Losinski, S. J.; Barnes, C. M. & Grover, B. K.
Partner: UNT Libraries Government Documents Department

Innovative subsurface stabilization project -- Final Report

Description: This is a report of results of applying four innovative grouting materials and one commercially available material for creating monoliths out of buried waste sites using jet grouting. The four innovative materials included a proprietary water-based epoxy, an Idaho National Engineering Laboratory-developed two-component grout that resembles hematite when cured with soil, molten low-temperature paraffin, and a proprietary iron oxide cement-based grout called TECT. The commercial grout was Type-H high-sulfate-resistant cement. These materials were tested in specially designed cold test pits that simulate buried transuranic waste at the Idaho National Engineering Laboratory. In addition to the grouting studies, specially designed field-scale permeameters were constructed to perform full-scale controlled mass balance hydraulic conductivity studies. An ungrouted field-scale permeameter contained simulated buried waste and soil and was left ungrouted, and a second identical field-scale permeameter was grouted with commercial-grade Type-H cement. The field demonstrations were performed in an area referred to as the Cold Test Pit at the Idaho National Engineering Laboratory. The Cold Test Pit is adjacent to the laboratory`s Radioactive Waste Management Complex. At the complex, 2 million ft{sup 3} of transuranic waste is commingled with 6--8 million ft{sup 3} of soil in shallow land burial, and improving the confinement of this waste is one of the options for final waste disposition. This report gives results of grouting, coring, hydraulic conductivity, and destructive examination of the grouted buried waste matrix.
Date: November 1, 1996
Creator: Loomis, G.G.; Zdinak, A.P. & Bishop, C.W.
Partner: UNT Libraries Government Documents Department

Annual report of decommissioning and remedial action S&M activities for the Environmental Management Program at Oak Ridge National Laboratory, Oak Ridge, Tennessee

Description: The Oak Ridge National Laboratory (ORNL) Surveillance and Maintenance (S&M) Program performs a variety of activities to ensure that sites and facilities within its responsibility remain in a safe condition and in compliance with applicable regulations. All S&M Program activities during fiscal year (FY) 1997 were accomplished safely, with no health and safety incidents, no lost work days, and no environmental noncompliances. In addition, all activities were performed within schedule thresholds and under budget. Many remedial action (RA) sites and decontamination and decommissioning (D&D) facilities are inspected and maintained by the S&M Program. RA sites encompass approximately 650 acres and 33 D&D facilities, including 4 inactive reactors. During FY 1997, routine, preventative, and emergency maintenance activities were performed as needed at these sites and facilities. Stabilization activities were also performed to reduce risks and reduce future S&M costs. Major activities at the RA sites during FY 1997 included maintaining proper liquid levels in surface impoundments and inactive -liquid low-level waste storage tanks as well as installing a new cover at the tumulus pads in Waste Area Grouping (WAG) 6, planting trees in the First Creek Riparian Corridor, and performing over 900 well inspections. Postremediation monitoring was conducted at the 3001 Canal, Core Hole 8, the WAG 6 Resource Conservation and Recovery caps, and WAG 5 Seeps C and D; groundwater monitoring was performed in WAGs 4, 5, and 6 and at the 3001 Canal Well. At ORNL D&D facilities, significant accomplishments included contaminated lead brick removal, asbestos abatement, contaminated equipment and debris removal, and radiologically contaminated area painting.
Date: November 1, 1997
Partner: UNT Libraries Government Documents Department

Grout and Glass Performance in Support of Stabilization/Solidification of the MVST Tank Sludges

Description: Wastewater at Oak Ridge National Laboratory (ORNL) is collected, evaporated, and stored in the Melton Valley Storage Tanks (MVST) pending treatment for disposal. The waste separates into two phases: sludge and supematant. Some of the supematant from these tanks has been decanted, solidified into a grout, and stored for disposal as a solid low-level waste. The sludges in the tank bottoms have been accumulating ,for several years. Some of the sludges contain a high amount of gamma activity (e.g., `37CS concentration range of 0.01 3-11 MBq/g) and contain enough transuranic (TRU) radioisotopes to be classified as TRU wastes. Some Resource Conservation and Recovery Act (RCRA) metal concentrations are high enough in the available total constituent analysis for the MVST sludge to be classified as RCRA hazardous; therefore, these sludges are presumed to be mixed TRU waste.
Date: November 1, 1998
Creator: Gilliam, T.M. & Spence, R.D.
Partner: UNT Libraries Government Documents Department

G3 model of gas and liquid migration from grout containing radioactive waste

Description: Grout has been evaluated as a means of containing low-level radioactive waste for long-term disposal. Concerns about hydrogen and reactive gas generation in the Hanford Site grout disposal facility lead to the development of the G3 model, which has predicted buildup of radiolytically formed gases in the grout region and their migration to air-filled regions. The G3 model is a one-dimensional code that couples models of gas diffusion with two-phase gas and liquid flow. It was coupled to a compartment diffusion model and these models predicted the concentrations of hydrogen I nitrous oxide, and other gases in air-filled regions of the grout disposal facility. The results have served as the technical basis for safety studies. A unique finding of the G3 model was that a liquid return, or expulsion of unbound liquid from the grout region, could occur. This liquid return is driven by displacement caused by gas bubbles that form within the grout`s microstructure. Liquid return is very sensitive to the level of gas production, the geometry and design of the grout region, and the material properties of the grout. Experimental evidence and observations that support code predictions will be discussed in this paper.
Date: November 1, 1994
Creator: Roblyer, S. P.; Finfrock, S. H. & Powell, W. J.
Partner: UNT Libraries Government Documents Department

Separation processes for high-level radioactive waste treatment

Description: During World War II, production of nuclear materials in the United States for national defense, high-level waste (HLW) was generated as a byproduct. Since that time, further quantities of HLW radionuclides have been generated by continued nuclear materials production, research, and the commercial nuclear power program. In this paper HLW is defined as the highly radioactive material resulting from the processing of spent nuclear fuel. The HLW is the liquid waste generated during the recovery of uranium and plutonium in a fuel processing plant that generally contains more than 99% of the nonvolatile fission products produced during reactor operation. Since this paper deals with waste separation processes, spent reactor fuel elements that have not been dissolved and further processed are excluded.
Date: November 1, 1992
Creator: Sutherland, D. G.
Partner: UNT Libraries Government Documents Department

Waste receiving and processing module 2A mixing tests status report

Description: The purpose of this report is to document the Phase II test conditions, observations, and results of this work. This report provides additional mixing performance test data and rheologic data that provide further indications that there are clear and distinct advantages in the preliminary choice of high-shear mixing alone, and high-shear dispersion in combination with, or followed by, a low-speed type mixer/stirrer for WRAP 2A facility design. Another objective was to determine if significant scale-up problems might exist in the various mix and mixer designs. In the later Phase 2 tests the test material quantities were significantly larger than in the Phase 1 tests.
Date: November 18, 1994
Creator: Weber, J. R. & Hull, K. J.
Partner: UNT Libraries Government Documents Department

Effect of aluminate ions on the heat of hydration of cementitious waste forms

Description: During the hydration and setting of high-salt content liquid waste grouts, considerable heat is generated by exothermic reactions within the grout. These reactions include hydration reactions of cementitious solids and reactions between waste constituents and the solids. Adiabatic temperature rises exceeding 80{degrees}C have been estimated for grouts prepared with a dry blend of 47 wt % fly ash, 47 wt % blast furnace slag, and 6 wt % type I/II Portland cement (1) Performance criteria for grout disposal specify that the temperature of the grout waste form must not exceed 90{degrees}C (2) To counter the increase in temperature, inert solids were added to the ``47/47/6`` dry blend to reduce the amount of heat-generating solids, thereby decreasing the temperature rise. Based on preliminary results from adiabatic calorimetry, a dry blend consisting of 40 wt % limestone flour, 28 wt % class F fly ash, 28 wt % ground blast furnace slag, and 4 wt % type I/II Portland cement was selected for further testing.
Date: November 1, 1993
Creator: Lokken, R. O.
Partner: UNT Libraries Government Documents Department

Acute toxicity screening of Hanford Site waste grouts using aquatic invertebrates

Description: Waste grouts prepared by mixing a simulated nonradioactive liquid waste with a dry solids blend consisting of cement, fly ash, and clay were screened for their acute toxicity using aquatic invertebrates (D. magna, D. pulex, and C. dubia) as test organisms and a fluorogenic substrate (4-methylumbelliferyl b-d galactoside) as the toxic stress indicator. After one hour of exposing juvenile daphnids to grout extracts of varying concentrations, followed by a 15-minute reaction with the fluorogenic substrate, the degree of in vivo enzymatic inhibition was measured by the number of resulting fluorescent daphnids. The effective concentration at which 50% of the daphnids were adversely affected (EC50) values calculated by probit analysis were 2,877 mg/L, 2,983 mg/L, and 3,174 mg/L for D. pulex, D. magna, and C. dubia, respectively. The results indicated that the grout extracts studied are nonhazardous and not dangerous to daphnids.
Date: November 1, 1993
Creator: Rebagay, T. V.; Dodd, D. A.; Lockrem, L. L.; Powell, W. J. & Voogd, J. A.
Partner: UNT Libraries Government Documents Department

Task plan for TARA-II compaction and grouting demonstration. Environmental Restoration Program

Description: This task directly supports the corrective measures evaluation for the closure of Solid Waste Storage Area (SWSA) 6 but also supports technology development for the closure of other Oak Ridge National Laboratory (ORNL) SWSAs and waste management units. Previous demonstrations have established the effectiveness of dynamic compaction and in situ grouting in stabilizing burial trenches against subsidence, which would otherwise compromise the support of infiltration barrier structures designed to protect buried waste from leaching. In situ grouting with polyacrylamide has also been demonstrated to improve the hydrologic isolation of buried waste. Both of these stabilization techniques have been demonstrated on burial trenches that are situated well above the water table and, hence, are in a chronic unsaturated moisture regime. Further demonstrations of these shallow-land burial trench stabilization techniques are necessary to establish their effectiveness and safety when applied to burial trenches that are chronically inundated with groundwater.
Date: November 1, 1991
Creator: Spalding, B. P.
Partner: UNT Libraries Government Documents Department

Non-destructive examination of grouted waste

Description: This data report contains the results of ultrasonic pulse velocity (UPV) and unconfined compressive strength (USC) measurements on a grouted simulant of 106AN tank waste. This testing program was conducted according to the requirements detailed in WHC-1993a. If successful, these methods could lead to a system for the remote verification of waste form quality. The objectives of this testing program were: to determine if a relationship exists between the velocity of ultrasonic compression waves and the unconfined compressive strength of simulated grouted waste, and if so, determine if the relationship is a valid method for grout quality assessment; and to determine if a relationship exists between the attenuation of wave amplitude and the age of test specimens. The first objective was met, in that a relationship between the UPV waves and USC was determined. This method appears to provide a valid measure of the quality of the grouted waste, as discussed in Sections 3.0 and 4.0. The second objective, to determine if the attenuation of UPV waves was related to the age of test specimens was partially met. A relationship does exist between wave amplitude and age, but it is doubtful that this method alone can be used to verify the overall quality of grouted waste. Section 2.0 describes the test methods, with the results detailed in Section 3.0. A discussion of the results are provided in Section 4.0.
Date: November 18, 1994
Creator: Benny, H. L.
Partner: UNT Libraries Government Documents Department

Approximation functions for airblast environments from buried charges

Description: In EMI report E 1/93, ``Airblast Environments from Buried HE-Charges,`` fit functions were used for the compact description of blastwave parameters. The coefficients of these functions were approximated by means of second order polynomials versus DOB. In most cases, the agreement with the measured data was satisfactory; to reduce remaining noticeable deviations, an approximation by polygons (i.e., piecewise-linear approximation) was used instead of polynomials. The present report describes the results of the polygon approximation and compares them to previous data. We conclude that the polygon representation leads to a better agreement with the measured data.
Date: November 1, 1993
Creator: Reichenbach, H.; Behrens, K. & Kuhl, A. L.
Partner: UNT Libraries Government Documents Department

In situ containment and stabilization of buried waste. Annual report FY 1992

Description: The objective of the project was to develop, demonstrate and implement advanced grouting materials for the in-situ installation of impermeable, durable subsurface barriers and caps around waste sites and for the in-situ stabilization of contaminated soils. Specifically, the work was aimed at remediation of the Chemical Waste (CWL) and Mixed Waste Landfills (MWL) at Sandia National Laboratories (SNL) as part of the Mixed Waste Landfill Integrated Demonstration (MWLID). This report documents this project, which was conducted in two subtasks. These were (1) Capping and Barrier Grouts, and (2) In-situ Stabilization of Contaminated Soils. Subtask 1 examined materials and placement methods for in-situ containment of contaminated sites by subsurface barriers and surface caps. In Subtask 2 materials and techniques were evaluated for in-situ chemical stabilization of chromium in soil.
Date: November 1, 1992
Creator: Allan, M. L.; Kukacka, L. E. & Heiser, J. H.
Partner: UNT Libraries Government Documents Department

DWPF saltstone study: Effects of thermal history on leach index and physical integrity. Part 2, Final report: Revision 1

Description: This report summarizes the observations made during the curing and testing of DWPF simulated saltstones which have been cured under isothermal conditions in sealed glass envelopes at temperatures from room temperature to 95{degrees}C. This study was performed to evaluate the effect of curing at and around temperatures representing conditions created within large pours of grout. There appears to be no difference in the leaching resistance of samples cured at the same temperature for varying times to 1 year. Curing at higher temperatures decreases the effective diffusivity of this waste formulation. These results are encouraging in that leaching resistance for samples near the expected maximum vault temperature (55{degrees}C) show effective diffusion coefficients (D{sub effective} {approximately}10{sup {minus}8} cm{sup 2}/sec) that agree with previous work and values that are believed to adequately protect the groundwater. The isothermal conditions of these tests simulate the nearly adiabatic conditions existing near the centerline of the monolith. The elevated temperatures due to hydration heat decrease over long times. This has been simulated by a series (1X) of staged isothermal cures. Since modeling indicated it would take nearly two years for emplaced grout to cool to near ambient temperatures, accelerated (2X) cooling curves were also tested. Specimens cured under these staged-isothermal conditions appear to be no different from specimens cured under isothermal conditions for the same time at the maximum temperature. The unexpected generation of nitrous oxide within saltstone creates internal stresses which cause fracturing when exposed to leaching conditions. Such fracturing is not considered significant for saltstone emplaced in engineered vaults for disposal.
Date: November 18, 1992
Creator: Orebaugh, E. G.
Partner: UNT Libraries Government Documents Department

Task plan to evaluate the effectiveness of in situ grouting of an ORNL waste burial trench with a cement-based grout. Environmental Restoration Program

Description: This task will demonstrate the feasibility of using an in situ grouting technique with a particulate-grout formulation as a closure action to stabilize waste trenches in Solid Waste Storage Area (SWSA) 6. It also supports technology development for closure of other SWSAs. A particulate grout will be formulated using cement-bentonite and fly ash from a coal-fired power plant. The grout solids will be dry-blended, mixed with water, and injected (using {similar_to}5 to 10 lb/in.{sup 2} pressure) into five injection wells per trench. After 28 days for setting, soil penetration resistance and hydraulic conductivity measurements will be repeated for comparison to pregrouting measurements. The primary objective of this task is to demonstrate the feasibility and effectiveness of the in situ injection of a particulate grout into waste burial trenches. Effectiveness is defined here as increased trenched stability (characterized by trench penetration resistance tests) and decreased potential for leachate migration (characterized by hydraulic conductivity tests).
Date: November 1, 1991
Creator: Francis, C. W.
Partner: UNT Libraries Government Documents Department

In situ containment and stabilization of buried waste

Description: The objective of the project was to develop, demonstrate and implement advanced grouting materials for the in-situ installation of impermeable, durable subsurface barriers and caps around waste sites and for the in-situ stabilization of contaminated soils. Specifically, the work was aimed at remediation of the Chemical Waste (CWL) and Mixed Waste Landfills (MWL) at Sandia National Laboratories (SNL) as part of the Mixed Waste Landfill Integrated Demonstration (MWLID). This report documents this project, which was conducted in two subtasks. These were (1) Capping and Barrier Grouts, and (2) In-situ Stabilization of Contaminated Soils. Subtask 1 examined materials and placement methods for in-situ containment of contaminated sites by subsurface barriers and surface caps. In Subtask 2 materials and techniques were evaluated for in-situ chemical stabilization of chromium in soil.
Date: November 1, 1992
Creator: Allan, M.L.; Kukacka, L.E. & Heiser, J.H.
Partner: UNT Libraries Government Documents Department

Task plan to evaluate the effectiveness of in situ grouting of an ORNL waste burial trench with a cement-based grout

Description: This task will demonstrate the feasibility of using an in situ grouting technique with a particulate-grout formulation as a closure action to stabilize waste trenches in Solid Waste Storage Area (SWSA) 6. It also supports technology development for closure of other SWSAs. A particulate grout will be formulated using cement-bentonite and fly ash from a coal-fired power plant. The grout solids will be dry-blended, mixed with water, and injected (using {similar to}5 to 10 lb/in.{sup 2} pressure) into five injection wells per trench. After 28 days for setting, soil penetration resistance and hydraulic conductivity measurements will be repeated for comparison to pregrouting measurements. The primary objective of this task is to demonstrate the feasibility and effectiveness of the in situ injection of a particulate grout into waste burial trenches. Effectiveness is defined here as increased trenched stability (characterized by trench penetration resistance tests) and decreased potential for leachate migration (characterized by hydraulic conductivity tests).
Date: November 1, 1991
Creator: Francis, C.W.
Partner: UNT Libraries Government Documents Department

Task plan for TARA-II compaction and grouting demonstration

Description: This task directly supports the corrective measures evaluation for the closure of Solid Waste Storage Area (SWSA) 6 but also supports technology development for the closure of other Oak Ridge National Laboratory (ORNL) SWSAs and waste management units. Previous demonstrations have established the effectiveness of dynamic compaction and in situ grouting in stabilizing burial trenches against subsidence, which would otherwise compromise the support of infiltration barrier structures designed to protect buried waste from leaching. In situ grouting with polyacrylamide has also been demonstrated to improve the hydrologic isolation of buried waste. Both of these stabilization techniques have been demonstrated on burial trenches that are situated well above the water table and, hence, are in a chronic unsaturated moisture regime. Further demonstrations of these shallow-land burial trench stabilization techniques are necessary to establish their effectiveness and safety when applied to burial trenches that are chronically inundated with groundwater.
Date: November 1, 1991
Creator: Spalding, B.P.
Partner: UNT Libraries Government Documents Department

Separation processes for high-level radioactive waste treatment

Description: During World War II, production of nuclear materials in the United States for national defense, high-level waste (HLW) was generated as a byproduct. Since that time, further quantities of HLW radionuclides have been generated by continued nuclear materials production, research, and the commercial nuclear power program. In this paper HLW is defined as the highly radioactive material resulting from the processing of spent nuclear fuel. The HLW is the liquid waste generated during the recovery of uranium and plutonium in a fuel processing plant that generally contains more than 99% of the nonvolatile fission products produced during reactor operation. Since this paper deals with waste separation processes, spent reactor fuel elements that have not been dissolved and further processed are excluded.
Date: November 1, 1992
Creator: Sutherland, D. G.
Partner: UNT Libraries Government Documents Department

DWPF saltstone study: Effects of thermal history on leach index and physical integrity

Description: This report summarizes the observations made during the curing and testing of DWPF simulated saltstones which have been cured under isothermal conditions in sealed glass envelopes at temperatures from room temperature to 95[degrees]C. This study was performed to evaluate the effect of curing at and around temperatures representing conditions created within large pours of grout. There appears to be no difference in the leaching resistance of samples cured at the same temperature for varying times to 1 year. Curing at higher temperatures decreases the effective diffusivity of this waste formulation. These results are encouraging in that leaching resistance for samples near the expected maximum vault temperature (55[degrees]C) show effective diffusion coefficients (D[sub effective] [approximately]10[sup [minus]8] cm[sup 2]/sec) that agree with previous work and values that are believed to adequately protect the groundwater. The isothermal conditions of these tests simulate the nearly adiabatic conditions existing near the centerline of the monolith. The elevated temperatures due to hydration heat decrease over long times. This has been simulated by a series (1X) of staged isothermal cures. Since modeling indicated it would take nearly two years for emplaced grout to cool to near ambient temperatures, accelerated (2X) cooling curves were also tested. Specimens cured under these staged-isothermal conditions appear to be no different from specimens cured under isothermal conditions for the same time at the maximum temperature. The unexpected generation of nitrous oxide within saltstone creates internal stresses which cause fracturing when exposed to leaching conditions. Such fracturing is not considered significant for saltstone emplaced in engineered vaults for disposal.
Date: November 18, 1992
Creator: Orebaugh, E.G.
Partner: UNT Libraries Government Documents Department