4,299 Matching Results

Search Results

Advanced search parameters have been applied.

Phase I Field Test Results of an Innovative DNAPL Remediation Technology: The Hydrophobic Lance

Description: An innovative technology for recovery of pure phase DNAPL was deployed in the subsurface near the M-Area Settling Basin, continuing the support of the A/M Area Ground Water Corrective Action Program (per Part B requirements). This technology, the Hydrophobic Lance, operates by placing a neutral/hydrophobic surface (Teflon) in contact with the DNAPL. This changes the in situ conditions experienced by the DNAPL, allowing it to selectively drain into a sump from which it can be pumped. Collection of even small amounts of DNAPL can save years of pump-and-treat operation because of the generally low solubility of DNAPL components.
Date: January 28, 1999
Creator: Tuck, D.M.
Partner: UNT Libraries Government Documents Department

Natural Circulation in the Blanket Heat Removal System During a Loss-of-Pumping Accident (LOFA) Based on Initial Conceptual Design

Description: A transient natural convection model of the APT blanket primary heat removal (HR) system was developed to demonstrate that the blanket could be cooled for a sufficient period of time for long term cooling to be established following a loss-of-flow accident (LOFA). The particular case of interest in this report is a complete loss-of-pumping accident. For the accident scenario in which pumps are lost in both the target and blanket HR systems, natural convection provides effective cooling of the blanket for approximately 68 hours, and, if only the blanket HR systems are involved, natural convection is effective for approximately 210 hours. The heat sink for both of these accident scenarios is the assumed stagnant fluid and metal on the secondary sides of the heat exchangers.
Date: October 7, 1998
Creator: Hamm, L.L.
Partner: UNT Libraries Government Documents Department

Closure Welding Design and Justification for Canister S00645 (Bent Flange)

Description: This report provides the design basis and justification for a closure welding technique using the manual Gas Tungsten Are Welding (GTAW) process. Other aspects affecting closure of Canister S00645, e.g., shielding, facility and administrative requirements, etc., are addressed elsewhere.
Date: December 21, 1998
Creator: Cannell, G.R.
Partner: UNT Libraries Government Documents Department

Analytical Study of High Concentration PCB Paint at the Heavy Water Components Test Reactor

Description: This report provides results of an analytical study of high concentration PCB paint in a shutdown nuclear test reactor located at the US Department of Energy's Savannah River Site (SRS). The study was designed to obtain data relevant for an evaluation of potential hazards associated with the use of and exposure to such paints.
Date: October 21, 1998
Creator: Lowry, N.J.
Partner: UNT Libraries Government Documents Department

Results of the DWPF Melter Drain Canister, S00209

Description: The Savannah River Technology Center (SRTC) was requested by the Engineering Section of the Defense Waste Processing Facility (DWPF) to characterize the drain canister filled during the DWPF Proficiency Runs. Testing of this canister, along with testing of the glass samples taken from the canister, was performed as part of a continuing effort to demonstrate compliance with the Waste Acceptance Product Specifications (WAPS)1 as outlined in the Waste Form Qualification Coordinating Plan (QCP).2. This report is a summary of the results of the canister filled with glass from the melter drain valve during the DWPF Proficiency Runs. This summary includes the results necessary for Waste Qualification, as well as results and observations from other SRTC tests.
Date: September 18, 1998
Creator: Andrews, M.K.
Partner: UNT Libraries Government Documents Department

Predictive Models for the Determination of Pitting Corrosion Versus Inhibitor Concentrations and Temperature for Radioactive Sludge in Carbon Steel Waste Tanks

Description: Statistical models have been developed to predict the occurrence of pitting corrosion in carbon steel waste storage tanks exposed to radioactive nuclear waste. The levels of nitrite concentrations necessary to inhibit pitting at various temperatures and nitrate concentrations were experimentally determined via electrochemical polarization and coupon immersion corrosion tests. Models for the pitting behavior were developed based on various statistical analyses of the experimental data. Feed-forward Artificial Neural Network (ANN) models, trained using the Back-Propagation of Error Algorithm, more accurately predicted conditions at which pitting occurred than the logistic regression models developed using the same data.
Date: October 6, 1998
Creator: Mickalonis, J.I.
Partner: UNT Libraries Government Documents Department

Dibutyl Phosphoric Acid Solubility in High-Acid, Uranium-Bearing Solutions at SRS

Description: The Savannah River Site has enriched uranium (EU) solution which has been stored for almost 10 years since being purified in the second uranium cycle of the H area solvent extraction process. The concentrations in solution are approximately 6 g/L U and about 0.1 M nitric acid. Residual tributylphosphate in the solutions has slowly hydrolyzed to form dibutyl phosphoric acid (HDBP) at concentrations averaging 50 mg/L. Uranium is known to form compounds with the dibutylphosphate ion (DBP) which have limited solubility. The potential to form uranium-DBP solids raises a nuclear criticality safety issue. Prior SRTC tests (WSRC-TR-98-00188) showed that U-DBP solids precipitate at concentrations potentially attainable during the storage of enriched uranium solutions. Furthermore, evaporation of the existing EUS solution without additional acidification could result in the precipitation of U-DBP solids if the DBP concentration in the resulting solution exceeds 110 mg/L at ambient temperature. The same potential exists for evaporation of unwashed 1CU solutions. As a follow-up to the earlier studies, SRTC studied the solubility limits for solutions containing acid concentrations above 0.5M HNO3. The data obtained in these tests reveals a shift to higher levels of DBP solubility above 0.5M HNO3 for both 6 g/L and 12 g/L uranium solutions. Analysis of U-DBP solids from the tests identified a mixture of different molecular structures for the solids created. The analysis distinguished UO2(DBP)2 as the dominant compound present at low acid concentrations. As the acid concentration increases, the crystalline UO2(DBP)2 shows molecular substitutions and an increase in amorphous content. Further analysis by methods not available at SRS will be needed to better identify the specific compounds present. This data indicates that acidification prior to evaporation can be used to increase the margin of safety for the storage of the EUS solutions. Subsequent experimentation evaluated options for absorbing HDBP from ...
Date: October 2, 1998
Creator: Pierce, R.A.
Partner: UNT Libraries Government Documents Department

Strontium and Actinides Removal from Savannah River Site Actual Waste Samples by Freshly Precipitated Manganese Oxide

Description: The authors investigated the performance of freshly precipitated manganese oxide and monosodium titanate (MST) for the removal of strontium (Sr) and actinides from actual high-level waste. Manganese oxide precipitation occurs upon addition of a reductant such as formate (HCO2-) or peroxide (H2O2) to a waste solution containing permanganate (MnO4-). Tests described in this document address the capability of manganese oxide treatment to remove Rs, Pu, and Np from actual high-level waste containing elevated concentrations of Pu. Additionally, tests investigate MST (using two unique batches) performance with the same waste for direct comparison to the manganese oxide performance.
Date: October 30, 2003
Creator: Barnes, M.J.
Partner: UNT Libraries Government Documents Department

Ion Chamber Compensation Tests

Description: The purpose of this report is to present the results of a series of tests performed to determine the need for gamma compensation of the ion chambers used to monitor the neutron flux in the 100 Area reactors.
Date: February 14, 2003
Creator: Mallard, R.L. Jr.
Partner: UNT Libraries Government Documents Department

Analysis of Events Associated with First Charge of Desicooler Material

Description: HB-Line's mission included dissolution of uranium-aluminum scrap left over from a U3O8 scrap recovery program begun in 1972 with material returned from Rocky Flats and Oak Ridge. This material has been stored in desicooler containers, and is commonly referred to as the Desicoolers. The Scrap Recovery process includes the dissolution of scrap material and transfer of the resulting solution to H-Canyon for further disposition. During the first charge of this material into the HB-Line dissolvers, the solution heated to boiling without external heat being added. Yellow-colored fumes, which dissipated rapidly, were noted in the glovebox by operators, and a small amount of liquid was noted in the glovebox by operations after dissolver cooldown. This technical report documents analysis of the data from the event with respect to potential Safety Basis violation and the Integrated Safety Management System process. Based on the analysis presented, the safety basis has shown its ability to protect the worker, the facility and the public.
Date: September 15, 2003
Creator: Alexander, D.E.
Partner: UNT Libraries Government Documents Department

Modeling of the Savannah River Site High Level Waste Evaporator Systems

Description: Three evaporators are used to reduce the volume of waste in the waste tank farm at the Savannah River Site (SRS). Evaporators are crucial operation in the SRS waste processing and management system. Using the Aspen Custom Modeler(TM) (ACM) software package marketed by Aspen Technology, Inc., the evaporator dynamic flowsheet models have been constructed to simulate the behavior of the evaporator systems. The evaporator models are used to assist operations and planning. The models account for the basic arrangement and flowpath for the evaporators: (1) Feed system, (2) Concentrate system, (3) Overheads system, and (4) Steam system. This paper provides a detailed description of the model development and presents the result of a typical simulation scenario.
Date: February 19, 2003
Creator: Hang, T.
Partner: UNT Libraries Government Documents Department

Discovery of Apparent Inconsistency Between Saltstone Waste Acceptance Criteria and the Saltstone Performance Assessment

Description: The intent of this document is to provide an evaluation to determine if the discovered condition (apparent inconsistency between the Saltstone Waste Acceptance Criteria (WAC) and the Saltstone PA) is within the assumptions, parameters, and bases of the approved PA and CA. If it is, then this document serves as the technical basis for authorizing the condition. If not, then, in order to authorize the activity, the PA and CA would need to be updated as appropriate and DOE approval sought of the update (special analysis or revision of the PA or CA).
Date: June 3, 2002
Creator: Wilhite, E.L.
Partner: UNT Libraries Government Documents Department

Effects of Elevated Radon Levels on Kanne Tritium Monitors

Description: The Savannah River Site has used Kanne ionization chambers since the late 1950's to monitor for airborne tritium in reactor facilities. Two Kanne monitors indicated elevated airborne tritium levels while monitoring a non-ventilated room used to store tritiated liquid moderator. Subsequent air sample analysis failed to reveal the presence of airborne tritium. It was suspected that elevated radon levels caused the Kanne monitors to falsely indicate tritium activity. Two commercially available monitoring systems were used to quantify radon levels in the storage room. Measurements performed during this evaluation found that radon caused the Kanne monitors in the storage room to falsely indicate the presence of airborne tritium. A side-by-side comparison of a filtered versus an unfiltered Kanne monitor found that a high efficiency particulate filter reduced monitor response to near background under high radon conditions. It was recommended that a high efficiency filter be installed on the dedicated storage room Kanne monitor and that the room be de-posted as an Airborne Radioactivity Area. It was also found that the Kanne monitors would detect a spill from a single drum of moderator within minutes and the dose rate due to tritium exposure at 20 hours following this spill would be 4.56 rem/hour.
Date: November 24, 2003
Creator: Farrell, W.E.
Partner: UNT Libraries Government Documents Department

Estimated Duration of the Subsurface Reducing Environment Produced by the Z-Area Saltstone Disposal Facility

Description: The formula for saltstone includes approximately 25 per cent wt slag to create a reducing environment for mitigating the subsurface transport of a number of radionuclides, including technetium-99. Based on laboratory measurements and mass balance calculations, it was estimated that the Z-Area saltstone waste form will maintain a reducing environment for more than a thousand years and likely for more than 10,000 years. The calculations were very sensitive to infiltration flow rate, underscoring the importance of the proposed moisture barrier for mitigating contaminant transport. Laboratory measurements indicated that the slag used in the formulation of the saltstone has an exceptionally high reduction capacity. Furthermore, measurements of a subsurface SRS sediment indicated that it also had a significant reduction capacity, albeit almost an order of magnitude less than that of the slag. Approximately 78 percent of the reduction capacity in the disposal system came from the saltstone, 1 4 percent from the geological materials in the overlying moisture barrier, and 9 percent from the vault made from reducing grout. This version differs from the original (WSRC-RP-2003-00362, Rev. 0) in that additional text was added to further explain the assumptions of the calculations and some typographical errors were corrected.
Date: October 3, 2003
Creator: Kaplan, D.I.
Partner: UNT Libraries Government Documents Department

Development of Chemical Treatment Alternatives for Tetraphenylborate Destruction in Tank 48H

Description: This study assessed chemical treatment options for decomposing the tetraphenylborate in High Level Waste (HLW) Tank 48H. Tank 48H, located at the Savannah River Site in Aiken, SC, contains approximately one million liters of HLW. The tetraphenylborate slurry represents legacy material from commissioning of an In Tank Precipitation process to separate radioactive cesium and actinides from the nonradioactive chemicals. During early operations, the process encountered an unplanned chemical reaction that catalytically decomposed the excess tetraphenylborate producing benzene. Subsequent research indicated that personnel could not control the operations within the existing equipment to both meet the desired treatment rate for the waste and maintain the benzene concentration within allowable concentrations. Since then, the Department of Energy selected an alternate treatment process for handling high-level waste at the site. However, the site must destroy the tetraphenylborate before returning the tank to HLW service. The research focuses on identifying treatments to decompose tetraphenylborate to the maximum extent feasible, with a preference for decomposition methods that produce carbon dioxide rather than benzene. A number of experiments examined whether the use of oxidants, catalysts or acids proved effective in decomposing the tetraphenylborate. Additional experiments developed an understanding of the solid, liquid and gas decomposition products.
Date: March 11, 2003
Creator: Lambert, D.P.
Partner: UNT Libraries Government Documents Department

Evaluation of Proposed New LLW Disposal Activity: Disposal of Aqueous PUREX Waste Stream in the Saltstone Disposal Facility

Description: The Aqueous PUREX waste stream from Tanks 33 and 35, which have been blended in Tank 34, has been identified for possible processing through the Saltstone Processing Facility for disposal in the Saltstone Disposal Facility.
Date: October 9, 2003
Creator: Cook, J.R.
Partner: UNT Libraries Government Documents Department