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Oral History Interview with George Riley, February 3, 1994

Access: Use of this item is restricted to the UNT Community
Interview with George Riley concerning his experiences while employed by the Civilian Conservation Corps during the Great Depression. Riley worked at camps in Duncan, Arizona (Company 1814); Fredonia, Arizona (Company 1814); and Grand Junction, Colorado (Company 3892).
Date: February 3, 1994
Creator: Henley, Shelly & Riley, George V.
Object Type: Book
System: The UNT Digital Library
Environmental Assessment of Remedial Action at the Maybell Uranium Mill Tailings Site Near Maybell, Colorado: Revision 2 (open access)

Environmental Assessment of Remedial Action at the Maybell Uranium Mill Tailings Site Near Maybell, Colorado: Revision 2

The purpose of this environmental assessment (EA) is to evaluate the environmental impacts resulting from remedial action at the Maybell uranium mill tailings site near Maybell, Colorado. A biological assessment and a floodplain/wetlands assessment are included as part of this EA. This report and attachments describe the proposed action, affected environment, and environmental impacts associated with the proposed remedial action, including impacts to threatened and endangered species listed or proposed for listing by the US Fish and Wildlife Service (FWS).
Date: November 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Environmental Assessment of Remedial Action at the Slick Rock Uranium Mill Tailings Sites, Slick Rock, Colorado. Revision 1 (open access)

Environmental Assessment of Remedial Action at the Slick Rock Uranium Mill Tailings Sites, Slick Rock, Colorado. Revision 1

The Uranium Mill Tailings Radiation Control Act of 1978 (42 USC {section}7901 et seq.), hereafter referred to as the UMTRCA, authorized the US Department of Energy (DOE) to clean up two uranium mill tailings processing sites near Slick Rock, Colorado, in San Miquel County. Contaminated materials cover an estimated 63 acres of the Union Carbide (UC) processing site and 15 ac of the North Continent (NC) processing site. The sites are within 1 mile of each other and are adjacent to the Dolores River. The sites contain concrete foundations of mill buildings, tailings piles, and areas contaminated by windblown and waterborne radioactive tailings materials. The total estimated volume of contaminated materials is approximately 621,300 cubic yards (yd{sup 3}). In addition to the contamination in the two processing site areas, four VPs were found to contain contamination. As a result of the tailings being exposed to the environment, contamination associated with the UC and NC sites has leached into shallow ground water. Surface water has not been affected. The closest residence is approximately 0.3 air mi from either site. The proposed action is to remediate the UC and NC sites by removing all contaminated materials within the designing site boundaries or …
Date: September 1, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Role of polycrystallinity in CdTe and CuInSe{sub 2} photovoltaic cells. Annual subcontract report, 1 April 1992--31 March 1993 (open access)

Role of polycrystallinity in CdTe and CuInSe{sub 2} photovoltaic cells. Annual subcontract report, 1 April 1992--31 March 1993

This report describes work to conduct several investigations of thin-film polycrystalline solar cells. (1) An analysis of high-efficiency solar cells fabricated at the University of South Florida showed significant reduction in forward recombination current, and the cells were stable over a 3-month test period. (2) Transient voltage effects were documented in a large number of polycrystalline cells and were attributed to long-lived trapping states sensitive to voltage changes near one-half open-circuit voltage. (3) Collection efficiency and its voltage dependence were carefully calculated. The typical effect on photocurrent at operating voltages is about 2% for CuInSe{sub 2}, and less for other cells.
Date: February 1, 1994
Creator: Sites, J. R.
Object Type: Report
System: The UNT Digital Library
Diosmacycloalkanes as models for the formation of hydrocarbons from surface methylenes. Final report (open access)

Diosmacycloalkanes as models for the formation of hydrocarbons from surface methylenes. Final report

Assignment of the vibrational modes Of Os{sub 2}(CO){sub 8}(CHCH{sub 3}) and Os(CO){sub 4}(C{sub 2}H{sub 4)} has given fingerprint vibrational spectra for the following species when chemisorbed on metal catalyst surfaces: ethylidene and ethylene bound in a metallacyclopropane mode. The formation and fragmentation of diosmacyclobutanes have been shown to involve slippage of the outgoing olefin onto a single osmium, and associative exchange of the olefin from that site. The incorporation of vinylcyclopropane without rearrangement has confirmed the absence of a diradical intermediate. The anomalous stability of the diosmacyclobutane derived from trans-2-butene has proven due to greater destabilization (by the substituent methyls) of the slipped intermediate than of the ground state. Reaction of an osmacyclobutane with 1,3- or 1,2-dienes (allenes) gives 1,2 rather than 1,4 addition to the diosmium unit. Treatment of Os(CO){sub 4}(C{sub 2}H{sub 4}) with triflic acid results in the formation of Os(CO){sub 4}(C{sub 2}H{sub 5})OTf. The authors have found that the reaction of an aryl iodine(III) reagent with propargyl stannanes or silanes results in o-iodo propargyl arenes.
Date: April 25, 1994
Creator: Norton, J. R.
Object Type: Report
System: The UNT Digital Library
Remedial Action Plan and Site Design for Stabilization of the Inactive Uranium Processing Site at Naturita, Colorado. Remedial Action Selection Report, Appendix B of Attachment 2: Geology Report, Final (open access)

Remedial Action Plan and Site Design for Stabilization of the Inactive Uranium Processing Site at Naturita, Colorado. Remedial Action Selection Report, Appendix B of Attachment 2: Geology Report, Final

The uranium processing site near Naturita, Colorado, is one of 24 inactive uranium mill sites designated to be cleaned up by the US Department of Energy (DOE) under the Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA), 42 USC {section} 7901 et seq. Part of the UMTRCA requires that the US Nuclear Regulatory Commission (NRC) concur with the DOE`s remedial action plan (RAP) and certify that the remedial action conducted at the site complies with the standards promulgated by the US Environmental Protection Agency (EPA). Included in the RAP is this Remedial Action Selection Report (RAS), which describes the proposed remedial action for the Naturita site. An extensive amount of data and supporting information has been generated and evaluated for this remedial action. These data and supporting information are not incorporated into this single document but are included or referenced in the supporting documents. The RAP consists of this RAS and four supporting documents or attachments. This Attachment 2, Geology Report describes the details of geologic, geomorphic, and seismic conditions at the Dry Flats disposal site.
Date: March 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Remedial Action Plan and Site Design for Stabilization of the Inactive Uranium Mill Tailings Sites at Slick Rock, Colorado: Remedial Action Selection Report. Preliminary Final (open access)

Remedial Action Plan and Site Design for Stabilization of the Inactive Uranium Mill Tailings Sites at Slick Rock, Colorado: Remedial Action Selection Report. Preliminary Final

This proposed remedial action plan incorporates the results of detailed investigation of geologic, geomorphic, and seismic conditions at the proposed disposal site. The proposed remedial action will consist of relocating the uranium mill tailings, contaminated vicinity property materials, demolition debris, and windblown/waterborne materials to a permanent repository at the proposed Burro Canyon disposal cell. The proposed disposal site will be geomorphically stable. Seismic design parameters were developed for the geotechnical analyses of the proposed cell. Cell stability was analyzed to ensure long-term performance of the disposal cell in meeting design standards, including slope stability, settlement, and liquefaction potential. The proposed cell cover and erosion protection features were also analyzed and designed to protect the RRM (residual radioactive materials) against surface water and wind erosion. The location of the proposed cell precludes the need for permanent drainage or interceptor ditches. Rock to be used on the cell top-, side-, and toeslopes was sized to withstand probable maximum precipitation events.
Date: March 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Baseline Risk Assessment of Groundwater Contamination at the Uranium Mill Tailings Site Near Gunnison, Colorado. Revision 1 (open access)

Baseline Risk Assessment of Groundwater Contamination at the Uranium Mill Tailings Site Near Gunnison, Colorado. Revision 1

This report evaluates potential impacts to public health or the environment resulting from groundwater contamination at the former uranium mill processing site. The tailings and other contaminated material at this site are being placed in an off-site disposal cell by the US Department of Energy`s (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating groundwater contamination. This is the second risk assessment of groundwater contamination at this site. The first risk assessment was performed primarily to evaluate existing domestic wells to determine the potential for immediate human health and environmental impacts. This risk assessment evaluates the most contaminated groundwater that flows beneath the processing site towards the Gunnison River. The monitor wells that have consistently shown the highest concentration of most contaminants are used in this risk assessment. This risk assessment will be used in conjunction with additional activities and documents to assist in determining what remedial action is needed for contaminated groundwater at the site after the tailings are relocated. This risk assessment follows an approach outlined by the US Environmental Protection Agency (EPA). The first step is to evaluate groundwater data collected from monitor wells at the site. Evaluation of these data showed …
Date: April 1, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Remedial Action Plan and Site Design for Stabilization of the Inactive Uranium Mill Tailings Sites at Slick Rock, Colorado. Attachment 3, Ground Water Hydrology Report: Preliminary Final (open access)

Remedial Action Plan and Site Design for Stabilization of the Inactive Uranium Mill Tailings Sites at Slick Rock, Colorado. Attachment 3, Ground Water Hydrology Report: Preliminary Final

The US Environmental Protection Agency (EPA) has established health and environmental protection regulations to correct and prevent ground water contamination resulting from processing activities at inactive uranium milling sites (52 FR 36000 (1987)). According to the Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978, 42 USC {section}7901 et seq., the US Department of Energy (DOE) is responsible for assessing the inactive uranium processing sites. The DOE has determined that for Slick Rock, this assessment shall include hydrogeologic site characterization for two separate uranium processing sites, the Union Carbide (UC) site and the North Continent (NC) site, and for the proposed Burro Canyon disposal site. The water resources protection strategy that describes how the proposed action will comply with the EPA ground water protection standards is presented in Attachment 4. The following site characterization activities are discussed in this attachment: Characterization of the hydrogeologic environment, including hydrostratigraphy, ground water occurrence, aquifer parameters, and areas of recharge and discharge. Characterization of existing ground water quality by comparison with background water quality and the maximum concentration limits (MCL) of the proposed EPA ground water protection standards. Definition of physical and chemical characteristics of the potential contaminant source, including concentration and leachability of …
Date: March 4, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Remedial Action Plan and Site Design for Stabilization of the Inactive Uranium Processing Site at Naturita, Colorado. Appendix B of Attachment 3: Groundwater Hydrology Report, Attachment 4: Water Resources Protection Strategy, Final (open access)

Remedial Action Plan and Site Design for Stabilization of the Inactive Uranium Processing Site at Naturita, Colorado. Appendix B of Attachment 3: Groundwater Hydrology Report, Attachment 4: Water Resources Protection Strategy, Final

Attachment 3 Groundwater Hydrology Report describes the hydrogeology, water quality, and water resources at the processing site and Dry Flats disposal site. The Hydrological Services calculations contained in Appendix A of Attachment 3, are presented in a separate report. Attachment 4 Water Resources Protection Strategy describes how the remedial action will be in compliance with the proposed EPA groundwater standards.
Date: March 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Remedial Action Plan and Site Design for Stabilization of the Inactive Uranium Processing Site at Naturita, Colorado. Appendix a of Attachment 3: Calculations, Final (open access)

Remedial Action Plan and Site Design for Stabilization of the Inactive Uranium Processing Site at Naturita, Colorado. Appendix a of Attachment 3: Calculations, Final

This report contains calculations for: hydraulic gradients for Alluvial Aquifer and Salt Wash Aquifer; slug test analysis to determine hydraulic conductivity for Alluvial Aquifer and Salt Wash Aquifer; average linear groundwater velocity for Alluvial Aquifer and Salt Wash Aquifer; statistical analysis of the extent of existing groundwater contamination; hydraulic gradients for Dakota/Burro Canyon Formation and Salt Wash Aquifer; slug test analysis to determine hydraulic conductivity for Dakota/Burro Canyon Formation and Perched Salt Wash Aquifer; determination of hydraulic conductivity of the Dakota/Burro Canyon Formation from Packer Tests; average linear groundwater velocity for Dakota/Burro Canyon and Salt Wash Aquifer; chemical and mineralogical characterization of core samples from the Dry Flats Disposal Site; and demonstration of low groundwater yield from Uppermost Aquifer.
Date: March 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Direct Methane Conversion to Methanol. Quarterly Project Status Report, January 1, 1994--March 31, 1994 (open access)

Direct Methane Conversion to Methanol. Quarterly Project Status Report, January 1, 1994--March 31, 1994

We proposed to demonstrate the effectiveness of a catalytic membrane reactor (a ceramic membrane combined with a catalyst) to solely produce methanol by partial oxidation of methane. Methanol is used as a chemical feedstock, gasoline additive, and turbine fuel. Methane partial oxidation using a catalytic membrane reactor has been determined as one of the promising approaches for methanol synthesis from methane. In the original proposal the membrane was used to selectively remove methanol from the reaction zone before carbon oxides form, thus increasing the methanol yield. Methanol synthesis and separation in one step would also make methane more valuable for producing chemicals and fuels. The cooling tube inserted inside the membrane reactor has created a low temperature zone that rapidly quenches the product stream. Both ceramic and metal membranes were tested in this study and similar results were obtained. This membrane reactor system has proved effective for increasing methanol selectivity during CH{sub 4} oxidation. We are currently using this non-isothermal non-permselective membrane reactor, and evaluating modifications to further improve performance. Metal membrane was used to avoid the membrane breakage problem. A series of experiments were carried out in order to optimize the operation of the process. A methanol yield of …
Date: September 1, 1994
Creator: Noble, R. D. & Falconer, J. L.
Object Type: Report
System: The UNT Digital Library
Gunnison, Colorado, Subpile Study Report (open access)

Gunnison, Colorado, Subpile Study Report

To protect human health and the environment, the UMTRA project will remediate the uranium mill tailings site at Gunnison, Colorado. There are explicit requirements (i.e., 40 Part CFR Part 192) for the surface remediation of radiologically contaminated soils on UMTRA sites. The removal of subpile sediment to the depth required by 40 CFR Part 192 will leave in place deeper foundation sediment that is contaminated with hazardous constituents other than radium-226 and thorium-230. The Department of Energy and the Colorado Department of Health have questioned whether this contaminated soil could potentially act as a continuing source of ground water contamination even after surface remediation based on 40 CFR Part 192 is complete. To evaluate the subpile sediments as a potential source of ground water contamination, the Gunnison subpile study was initiated. This report summarizes the results and findings of this study.
Date: March 1, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Long-Term Surveillance Plan for the Bodo Canyon Disposal Site, Durango, Colorado (open access)

Long-Term Surveillance Plan for the Bodo Canyon Disposal Site, Durango, Colorado

This long-term surveillance plan (LTSP) for the Durango, Colorado, Uranium Mill Tailings Remedial Action (UMTRA) Project disposal site describes the surveillance activities for the Durango (Bodo Canyon) disposal site, which will be referred to as the disposal site throughout this document. The US Department of Energy (DOE) will carry out these activities to ensure that the disposal site continues to function as designed. This LTSP was prepared as a requirement for acceptance under the US Nuclear Regulatory Commission (NRC) general license for custody and long-term care of residual radioactive materials (RRM). RRMs include tailings and other uranium ore processing wastes still at the site, which the DOE determines to be radioactive. This LTSP is based on the DOE`s Guidance for Implementing the UMTRA Project Long-term Surveillance Program (DOE, 1992).
Date: March 1, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Environmental Assessment of Remedial Action at the Naturita Uranium Processing Site Near Naturita, Colorado. Revision 3 (open access)

Environmental Assessment of Remedial Action at the Naturita Uranium Processing Site Near Naturita, Colorado. Revision 3

The proposed remedial action for the Naturita processing site is relocation of the contaminated materials and debris to the Dry Flats disposal site, 6 road miles (mi) [10 kilometers (km)] to the southeast. At the disposal site, the contaminated materials would be stabilized and covered with layers of earth and rock. The proposed disposal site is on land administered by the Bureau of Land Management (BLM) and used primarily for livestock grazing. The final disposal site would cover approximately 57 ac (23 ha), which would be permanently transferred from the BLM to the DOE and restricted from future uses. The remedial action activities would be conducted by the DOE`s Uranium Mill Tailings Remedial Action (UMTRA) Project. The proposed remedial action would result in the loss of approximately 162 ac (66 ha) of soils at the processing and disposal sites; however, 133 ac (55 ha) of these soils at and adjacent to the processing site are contaminated and cannot be used for other purposes. If supplemental standards are approved by the NRC and state of Colorado, approximately 112 ac (45 ha) of contaminated soils adjacent to the processing site would not be cleaned up. This area is steeply sloped. The cleanup …
Date: February 1, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Capillary discharge extreme ultraviolet lasers. Final report, December 15, 1990--February 28, 1994. Demonstration of a discharge pumped table-top soft x-ray laser (open access)
Properties of molecular solids and fluids at high pressure and temperature. Final report, March 1, 1986--October 31, 1993 (open access)

Properties of molecular solids and fluids at high pressure and temperature. Final report, March 1, 1986--October 31, 1993

The main thrust of this work was directed to the task of determining the thermodynamic behavior of condensed solids and fluids containing simple molecules. Properties calculated include specific heats, equations of state, compressibilities, sound velocities, virial coefficients, viscosities, and thermal expansion. In addition, details of the structural, orientational, and magnetic phase transitions were determined. Dynamical quantities calculated include the lattice, libron, and vibron mode frequencies at various pressures and temperatures. Also, we developed new techniques required to meet our objectives. One was a method for accurately calculating the Gibbs free energy of various phases. Another is the multiple-histogram Monte Carlo which can dramatically reduce computing time and can provide a continuous map of thermodynamic averages over a range of some thermodynamical variable.
Date: June 1, 1994
Creator: Etters, R. D.
Object Type: Report
System: The UNT Digital Library
Preparedness to Counsel HIV-Positive Clients: a Survey of Practitioners (open access)

Preparedness to Counsel HIV-Positive Clients: a Survey of Practitioners

This purpose of this study was to investigate and examine the attitudes of therapists who treat HIV-positive (HIV+) clients. Specifically, therapists' perceptions of their own preparedness in dealing with specific issues and emotions of HIV+ clients were examined. Also, therapists' evaluation of their own efficacy of specific therapeutic approaches with HIV+ clients was examined. These therapists' perceptions and evaluations of all their clients in general were compared to their HIV+ clients. Comparisons were also made within the two groups.
Date: December 1994
Creator: Rowe, Christina J. (Christina Jo)
Object Type: Thesis or Dissertation
System: The UNT Digital Library

[Photograph 2012.201.B0335.0472]

Photograph used for a newspaper owned by the Oklahoma Publishing Company. Caption: "Jeff Howard's Quadra foil is up. Howard is a kite maker from Breckenridge, Colo."
Date: July 2, 1994
Creator: Hoke, Doug
Object Type: Photograph
System: The Gateway to Oklahoma History
[Evolution of Sedimentary Basins--Paradox Basin: Chapters C and D] (open access)

[Evolution of Sedimentary Basins--Paradox Basin: Chapters C and D]

From abstract: The report for document C is about the tectonic trends of the northern part of the Paradox Basin of southeastern Utah and southwestern Colorado, as derived from Landsat multispectral scanner imaging and geophysical and geologic mapping. The report for document D is about an uncontrolled X-band airborn radar-image mosaic that was compiled for the western three-fifths of the Moab 1° x 2° quadrangle of southeastern Utah and southwestern Colorado.
Date: 1994
Creator: Friedman, Jules D.; Case, James E.; Simpson, Shirley L. & Heller, Joan S.
Object Type: Report
System: The UNT Digital Library
Environmental Assessment of Remedial Action at the Naturita Uranium Processing Site Near Naturita, Colorado. Revision 2 (open access)

Environmental Assessment of Remedial Action at the Naturita Uranium Processing Site Near Naturita, Colorado. Revision 2

The proposed remedial action for the Naturita processing site is relocation of the contaminated materials and debris to the Dry Flats disposal sits, 6 road miles (mi) [10 kilometers (km)) to the southeast. At the disposal site, the contaminated materials would be stabilized and covered with layers of earth and rock. The proposed disposal site is on land administered by the Bureau of Land Management (BLM) and used primarily for livestock grazing. The final disposal sits would cover approximately 57 ac (23 ha), which would be permanently transferred from the BLM to the DOE and restricted from future uses. The remedial action activities would be conducted by the DOE`s Uranium Mill Tailings Remedial Action (UMTRA) Project. The proposed remedial action would result in the loss of approximately 162 ac (66 ha) of soils at the processing and disposal sites; however, 133 ac (55 ha) of these soils at and adjacent to the processing site are contaminated and cannot be used for other purposes. If supplemental standards are approved by the NRC and state of Colorado, approximately 112 ac (45 ha) of contaminated soils adjacent to the processing site would not be cleaned up. This area is steeply sloped. The cleanup …
Date: January 1, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Economic Impact Study of the Uranium Mill Tailings Remedial Action Project in Colorado: Colorado State Fiscal Year 1994. Revision 1 (open access)

Economic Impact Study of the Uranium Mill Tailings Remedial Action Project in Colorado: Colorado State Fiscal Year 1994. Revision 1

The Colorado economic impact study summarizes employment and economic benefits to the state from activities associated with the Uranium Mill Tailings Remedial Action (UMTRA) Project during Colorado state fiscal year 1994 (1 July 1993 through 30 June 1994). To capture employment information, a questionnaire was distributed to subcontractor employees at the active UMTRA Project sites of Grand Junction, Naturita, Gunnison, and Rifle, Colorado. Economic data were requested from each site prime subcontractor, as well as from the Remedial Action Contractor. Information on wages, taxes, and subcontract expenditures in combination with estimates and economic multipliers is used to estimate the dollar economic benefits to Colorado during the state fiscal year. Finally, the fiscal year 1994 estimates are compared to fiscal year 1993 employment and economic information.
Date: December 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
UMTRA Project Water Sampling and Analysis Plan, Durango, Colorado (open access)

UMTRA Project Water Sampling and Analysis Plan, Durango, Colorado

Surface remedial action has been completed at the Uranium Mill Tailings Remedial Action Project in Durango, Colorado. Contaminated soil and debris have been removed from the former processing site and placed in the Bodo Canyon disposal cell. Ground water at the former uranium mill/tailings site and raffinate pond area has been contaminated by the former milling operations. The ground water at the disposal site was not impacted by the former milling operations at the time of the cell`s construction. Activities for fiscal 1994 involve ground water sampling and site characterization of the disposal site.
Date: January 1, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Baseline Risk Assessment of Ground Water Contamination at the Uranium Mill Tailings Sites Near Slick Rock, Colorado (open access)

Baseline Risk Assessment of Ground Water Contamination at the Uranium Mill Tailings Sites Near Slick Rock, Colorado

This baseline risk assessment of ground water contamination at the uranium mill tailings sites near Slick Rock, Colorado, evaluates potential public health and environmental impacts resulting from ground water contamination at the former North Continent (NC) and Union Carbide (UC) uranium mill processing sites. The tailings at these sites will be placed in a disposal cell at the proposed Burro Canyon, Colorado, site. The US Department of Energy (DOE) anticipates the start of the first phase remedial action by the spring of 1995 under the direction of the DOE`s Uranium Mill Tailings Remedial Action (UMTRA) Project. The second phase of the UMTRA Project will evaluate ground water contamination. This baseline risk assessment is the first site-specific document for these sites under the Ground Water Project. It will help determine the compliance strategy for contaminated ground water at the site. In addition, surface water and sediment are qualitatively evaluated in this report.
Date: November 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library