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Bench-scale studies with mercury contaminated SRS soil

Description: The Savannah River Technology Center (SRTC) has been charactered by the Department of Enregy (DOE) - Office of Technology Development (OTD) to investigate vitrification technology for the treatment of Low Level Mixed Wastes (LLMW). In fiscal year 1995, LLW streams containing mercury and organics were targeted. This report will present the results of studies with mercury contaminated waste. In order to successfully apply vitrification technology to LLMW, the types and quantities of glass forming additives necessary for producing homogeneous glasses from the wastes had to be determined, and the treatment for the mercury portion had to also be determined. The selected additives had to ensure that a durable and leach resistant waste form was produced, while the mercury treatment had to ensure that hazardous amounts of mercury were not released into the environment.
Date: May 8, 1996
Creator: Cicero, C.A.
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

Disposal of tritium-exposed metal hydrides

Description: A plan has been established for disposal of tritium-exposed metal hydrides used in Savannah River Site (SRS) tritium production or Materials Test Facility (MTF) R D operations. The recommended plan assumes that the first tritium-exposed metal hydrides will be disposed of after startup of the Solid Waste Disposal Facility (SWDF) Expansion Project in 1992, and thus the plan is consistent with the new disposal requiremkents that will be in effect for the SWDF Expansion Project. Process beds containing tritium-exposed metal hydride powder will be disposed of without removal of the powder from the bed; however, disposal of tritium-exposed metal hydride powder that has been removed from its process vessel is also addressed.
Date: January 1, 1991
Creator: Nobile, A. & Motyka, T.
Partner: UNT Libraries Government Documents Department

Documentation of toxicity testing results on increased supernate treatment rate of 2700 gallons/batch

Description: In February 1991, Reactor Materials increased the rate of supernate treatment in the M-Area Dilute Effluent Treatment Facility (DETF) from 1800 gallons to [approximately]2700 gallons of supernate per 36,000 gallon dilute wastewater batch. The first release of the treated effluent began on March 3, 1991. A series of whole effluent toxicity tests was conducted on the DETF effluent to determine if the increased supernate concentration would result in any chronic toxicity affects in the receiving stream (Tims Branch). The toxicity tests were conducted at instream concentrations equivalent to DETF release rates of 5, 10, 15, 20, and 25 gallons/min. The test results, based on 7-day Ceriodaphnia dubia chronic toxicity, indicated no toxicity effects at any concentration tested. Supernate treatment in DETF continued at the higher concentration.
Date: July 6, 1992
Creator: Pickett, J.B.
Partner: UNT Libraries Government Documents Department

Deuterium absorption and material phase characteristics of Zr[sub 2]Fe

Description: Scanning electron microscope (SEM) images of polished surfaces, electron probe microanalysis, and X-ray powder diffractometry indicated the presence of a continuous Zr[sub 2]Fe phase with secondary phases of ZrFe[sub 2], Zr[sub 5]FeSn, [alpha]-Zr, and Zr[sub 6]Fe[sub 3]O. A statistically-designed experiment to determine the effects of temperature, time, and vacuum quality On activation of St 198 revealed that when activated at low temperature (350[degrees]C) deuterium absorption rate was slower when the vacuum quality was pwr (2.5 Pa vs. 3[times]10[sup [minus]4] Pa). However, at higher activation temperature (500[degrees]C), deuterium absorption rate was fast and was independent of vacuum quality. Deuterium pressure-composition-temperature (P-C-T) data are reported for St 198 in the temperature range 200--500[degrees]C. The P-C-T data over the full range of deuterium loading and at temperatures of 350[degrees]C and below is described by: K[sub 0e]-([Delta]H[sub [alpha]]/RT)=PD[sub 2]q[sup 2]/(q*[minus]q)[sup 2] where [Delta]H[alpha] and K[sub 0] have values of 101.8 kJ[center dot]mole[sup [minus]1] and 3.24[times]10[sup [minus]8]Pa[sup [minus]1], and q* is 15.998 kPa[center dot]L[sup [minus]1][center dot]g[sup [minus]1]. At higher temperatures, one or more secondary reactions in the solid phase occur that slowly consume D[sub 2] from the gas phase. XRD suggests these reactions to be: 2 Zr[sub 2]FeD[sub x] [yields] x ZrD[sub 2] + x/3 ZrFe[sub 2] + (2 [minus] 2/3x) Zr[sub 2]Fe and Zr[sub 2]FeD[sub x] + (2 [minus]1/2x) D[sub 2] [yields] ZrD[sub 2] + Fe, where 0 < x < 3. Reaction between gas phase deuterium and Zr2FC formed in the first reaction accounts for the observed consumption of deuterium from the gas phase by this reaction.
Date: December 30, 1992
Creator: Nobile, A.; Mosley, W.C.; Holder, J.S. & Brooks, K.N.
Partner: UNT Libraries Government Documents Department

Effects of temperature and radiation on the nuclear waste glass product consistency leach test

Description: Previous leach studies carried out with monolithic glass samples have shown that glass dissolution rates increase with increasing temperature and may or may not increase on exposure to external gamma radiolysis. In this study we have investigated the effects of temperature (70--1200[degrees]C) and radiation on the dissolution of simulated radioactive waste glasses using the Product Consistency Test (PCT). The PCT is a seven day, crushed glass leach test in deionized water that is carried out at 9OO[degrees]C. To date our results indicate no significant effect of external Co--60 gamma radiation when testing various simulated waste glasses at 90[degrees]C in a wellinsulated compartment within a Gammacell 220 irradiation unit. The temperature dependence for glass dissolution clearly exhibits Arrheniustype behavior for two of the three glasses tested. For the third glass the dissolution decreases at the higher temperatures, probably due to saturation effects. Actual radioactive waste glasses will be investigated later as part of this study.
Date: January 1, 1993
Creator: Crawford, C.L. & Bibler, N.E.
Partner: UNT Libraries Government Documents Department

Effects of internal helium on mechanical properties of NITRONIC[trademark] 40 stainless steel

Description: This report describes results of tests on annealed Nitronic 40 stainless steel containing 0.0, 0.26, and 2.6 appM helium-3 (He-3), over the temperature range 25-842 C. Ultimate tensile strength, 0.2% offset yield strength, total elongation, uniform elongation, nonuniform elongation, and reduction-in-area were measured. The predominant effect of He-3 is decreased ductility caused by inhibition of necking. Annealed Nitronic 40 exhibits greater sensitivity to internal He-3 than solution-annealed Incoloy 903 and high-energy-rate forged 316L stainless steel.
Date: January 1, 1993
Creator: Mosley, W.C.
Partner: UNT Libraries Government Documents Department

Effluent versus inlet header break analysis for SRS-reactor LOPA scenario

Description: The Loss-of-Pumping Accident (LOPA) is a design basis accident for the Savannah River Site (SRS) reactors. The LOPA is defined as a Double Ended Guillotine Break (DEGB) in a secondary cooling water pipe. The secondary cooling line break is termed inlet or effluent depending on break location. Upon break detection emergency shut down procedure begins, the reactor scrams, secondary cooling pump motors trip off, primary cooling pump AC motors switch off, and DC motor drive engages. Secondary cooling gravity flow continues flooding the building after secondary cooling pumps are off. The Emergency Cooling System (ECS) activates before the DC motors flood out. Break detection time, header flooding rate, and flooding locations are different for the inlet and effluent header breaks due to different break locations. Inlet and effluent header break primary coolant temperature transients differ because primary and secondary cooling pumps continue during a break detection and reactor scram time delay for the effluent header case, whereas the pumps trip off almost immediately for the inlet header case. Design basis accident reactor core power limits are calculated for both the inlet and effluent header breaks.
Date: January 1, 1992
Creator: Paul, P.K.; Barbour, K.L. & Herman, D.T.
Partner: UNT Libraries Government Documents Department

Errors of DWPF Frit analysis

Description: Glass frit will be a major raw material for the operation of the Defense Waste Processing Facility. The frit will be controlled by certificate of conformance and a confirmatory analysis by a commercial laboratory. The following effort provides additional quantitative information on the variability of frit analyses at two commercial laboratories.
Date: January 24, 1992
Creator: Schumacher, R.F.
Partner: UNT Libraries Government Documents Department

Errors of DWPF frit analysis: Final report

Description: Glass frit will be a major raw material for the operation of the Defense Waste Processing Facility. The frit will be controlled by certificate of conformance and a confirmatory analysis from a commercial analytical laboratory. The following effort provides additional quantitative information on the variability of frit chemical analyses at two commercial laboratories. Identical samples of IDMS Frit 202 were chemically analyzed at two commercial laboratories and at three different times over a period of four months. The SRL-ADS analyses, after correction with the reference standard and normalization, provided confirmatory information, but did not detect the low silica level in one of the frit samples. A methodology utilizing elliptical limits for confirming the certificate of conformance or confirmatory analysis was introduced and recommended for use when the analysis values are close but not within the specification limits. It was also suggested that the lithia specification limits might be reduced as long as CELS is used to confirm the analysis.
Date: January 20, 1993
Creator: Schumacher, R.F.
Partner: UNT Libraries Government Documents Department

Estimated steady-state compositions of supernatant liquid during sludge washing

Description: Steady-state hydroxide, pH, carbonate and bicarbonate levels have been estimated for supernatant liquids during sludge washing and storage. These compositions were needed in order to prepare synthetic solutions for determining inhibitor requirements. The steady-state pH was plotted versus the nitrate concentration and fitted to a logarithmic expression of the form, pH = 10.23 [times] [NO[sub 3][minus]][sup 0.0178] where [NO[sub 3][minus]] is the concentration of nitrate in moles/liter. Similar expressions were also developed for calculating the concentrations of carbonate and bicarbonate as a function of the nitrate concentration.
Date: November 12, 1991
Creator: Hobbs, D.T.
Partner: UNT Libraries Government Documents Department

A comparison of the WIND System atmospheric models and MATS data

Description: Atmospheric transport and diffusion models have been developed by the Environmental Technology Section (ETS) of the Savannah River Technology Center to calculate the location and concentration of toxic or radioactive materials during an accidental release at the Savannah River Site (SRS). The output from these models has been used to support initial on-site and off-site emergency response activities such as protective action decision making and field monitoring coordination. These atmospheric transport and diffusion models have been incorporated into an automated computer-based system called the (Weather Information and Display) System and linked to real-time meteorological and radiological monitoring instruments to provide timely information for these emergency response activities (Hunter, 1990). This study will compare two of the WIND System annospheric models, PUFF/PLUME and 2DPUF, with a select group of MATS experiments and examine the results in detail to determine the performance of the models. Additional results from this study can be found in Fast et al. (1991).
Date: July 14, 1992
Creator: Fast, J.D.; Berman, S. & Addis, R.P.
Partner: UNT Libraries Government Documents Department

A comparison of the WIND System atmospheric models and RASCAL

Description: A detailed comparison of the characteristics of the WIND System atmospheric models and the NRC's RASCAL code was made. The modeling systems differ substantially in the way input is entered and the way output is displayed. Nevertheless, using the same source term and meteorological input parameters, the WIND System atmospheric models and RASCAL produce similar results in most situations. The WIND System atmospheric model predictions and those made by RASCAL are within a factor of two at least 70% of the time and are within a factor of four 89% of the time. Significant differences in the dose between the models may occur during conditions of low wind speeds, strong atmospheric stability, and/or wet deposition as well as for many atmospheric cases involving cloud shine. Even though the numerical results are similar in most cases, there are many site-specific and operational characteristics that have been incorporated into the WIND System atmospheric models to provide SRS emergency response personnel with a more effective emergency response tool than is currently available from using RASCAL.
Date: January 1, 1991
Creator: Fast, J.D.
Partner: UNT Libraries Government Documents Department

A comparison of ROChem reverse osmosis and spiral wound reverse osmosis membrane modules

Description: Testing of the ROChem Disc Tube[reg sign] reverse osmosis (RO) module's performance on biologically active feed waters has been completed. Both the ROChem module (using Filmtec standard-rejection seawater membranes) and the Filmtec spiral-wound membrane module (using Filmtec high-rejection seawater membranes) were tested with stimulant solutions containing typical bacteria and metal hydroxide levels found in the F/H Effluent Treatment Facility (ETF) influent. Results indicate that the ROChem module gave superior performance over the spiral-wound module. Water flux losses were reduced by over 30% for water recoveries above 40%.
Date: January 31, 1992
Creator: Siler, J. L.
Partner: UNT Libraries Government Documents Department

A comparison of the WIND System atmospheric models and MATS data

Description: The results produced by two of the WIND System atmospheric models, PUFF/PLUME and 2DPUF, were compared with a select group of eight MATS experiments to determine the performance of the models. Three of the MATS experiments employed TRAC vehicle sampling and the remaining five used a line of fixed samplers. The performance of the models was based on certain dispersion characteristics that are important in emergency response situations. Both PUFF/PLUME and 2DPUF were executed with the same source term and meteorological data. When the numerical results from the models were compared to the observed values from the MATS experiments, it was found that 2DPUF produced concentrations and plume widths that were closer to the observed values than PUFF/PLUME. Both models did not produce any bias in the values of the concentration when individual data points were examined; however, PUFF/PLUME consistently overpredicted the peak and total concentrations. 2DPUF did not exibit any bias in the peak and total concentrations. When wind direction errors were removed, 80--84% of the concentrations from PUFF/PLUME and 88% of the concentrations from 2DPUF where within a factor of 10 of the observed values. In some instances, both models were able to predict concentration values that were comparible to a more complex, three-dimensional model called MATHEW-ADPIC. Considering all of the possible uncertainties associated with dispersion modeling, PUFF/PLUME and 2DPUF performed reasonably well. The differences between the dispersion forecasts made by PUFF/PLUME and 2DPUF and the observed surface tracer concentration are very similar to many other emergency response models based on the Gaussian assumption.
Date: November 25, 1991
Creator: Fast, J.D.; Berman, S. & Addis, R.P.
Partner: UNT Libraries Government Documents Department

CTOD-based acceptance criteria for heat exchanger head staybolts. [Crack Tip Opening Displacement (CTOD)]

Description: The primary coolant piping system of the Savannah River Site (SRS) reactors contains twelve heat exchangers to remove the waste heat from the nuclear materials production. A large break at the inlet or outlet heads of the heat exchangers would occur if the restraint members of the heads become inactive. The heat exchanger head is attached to the tubesheet by 84 staybolts. The structural integrity of the heads is demonstrated by showing the redundant capacity of the staybolts to restrain the head at design conditions and under seismic loadings. The beat exchanger head is analyzed with a three- dimensional finite element model. The restraint provided by the staybolts is evaluated for several postulated cases of inactive or missing staybolts, that is, bolts that have a flaw exceeding the ultrasonic testing (UT) threshold depth of 25% of the bolt diameter. A limit of 6 inactive staybolts is reached with a fracture criterion based on the maximum allowable local displacement at the active staybolts which corresponds to the crack tip opening displacement (CTOD) of 0.032 inches. An acceptance criteria methodology has been developed to disposition flaws reported in the staybolt inspections while ensuring adequate restraint capacity of the staybolts to maintain integrity of the heat exchanger heads against collapse. The methodology includes an approach for the baseline and periodic inspections of the staybolts. A total of up to 6 staybolts, reported as containing flaws with depths at or exceeding 25% would be acceptable in the heat exchanger.
Date: January 1, 1992
Creator: Lam, P.S.; Sindelar, R.L.; Barnes, D.M. & Awadalla, N.G.
Partner: UNT Libraries Government Documents Department

Data banks for risk assessment at the Savannah River Site

Description: One of the lessons learned from many years of risk assessment experience is that mistakes of the past are soon forgotten if no method is available to retrieve and review these events. Savannah River Site has maintained a computerized data bank system for recording, retrieving and reviewing its incident history. The system is based on a series of compilations developed primarily for risk assessment but has been found to be invaluable for many other uses such as equipment reliability, project justification, and incident investigations.
Date: January 1, 1992
Creator: Durant, W.S.; Townsend, C.S.; Baughman, D.F. & Hang, P.
Partner: UNT Libraries Government Documents Department

Data acquisition system time measurement capabilities using WorkBench[trademark] software

Description: There is an increasing interest in the ability to measure transient behavior in the Heat Transfer Laboratory (HTL). To accomplish this the timing system behavior for the Data Acquisition Systems (DAS) must be evaluated. This report discusses the evaluation of a DAS timing system using WorkBench[trademark] Software in a Macintosh II environment. It also describes a method which can be successfully used to calibrate the timing system associated with the DAS.
Date: April 1, 1992
Creator: Coutts, D.A.
Partner: UNT Libraries Government Documents Department

Data banks of chemical substances and their toxicity

Description: Rapid proliferation in the development of new chemical compounds, coupled with the discovery and/or identification of those already in existence, has led to a significant need to investigate their physicochemical and biological properties, to document the knowledge gained, and to communicate that knowledge in as convenient a manner as possible. This paper presents and briefly discusses several prominent chemical databases.
Date: January 1, 1992
Creator: Craig, D.K.
Partner: UNT Libraries Government Documents Department

Demonstration of Eastman Christensen horizontal drilling system -- Integrated Demonstration Site, Savannah River Site

Description: An innovative horizontal drilling system was used to install two horizontal wells as part of an integrated demonstration project at the Savannah River Site (SRS), Aiken, South Carolina. The SRS is located in south-central South Carolina in the upper Coastal Plain physiographic province. The demonstration site is located near the A/M Area, and is currently known as the Integated Demonstration Site. The Department of Energy's Office of Technology Development initiated an integrated demonstration of innovative technologies for cleanup of volatile organic compounds (VOCS) in soils and groundwater at the SRS in 1989. The overall goal of the program is to demonstrate, at a single location, multiple technologies in the fields of drilling, characterization, monitoring, and remediation. Innovative technologies are compared to one another and to baseline technologies in terms of technical performance and cost effectiveness. Transfer of successfully demonstrated technologies and systems to DOE environmental restoration organizations, to other government agencies, and to industry is a critical part of the program.
Date: December 1, 1992
Partner: UNT Libraries Government Documents Department

Computer simulation of the time dependent contents of a tank containing transuranics

Description: The management of tanks containing radioactive waste requires the characterization of tank contents and an estimation of how those tank contents will change over time. The Savannah River Site (SRS) is currently in the process of characterizing a tank containing transuranic elements stored since the late 1970s. These isotopes are the by-products of a campaign to produce Pu-242 in the SRS reactors. In order to estimate the isotopic contents of this tank to the year 2100, a simulation, based largely on the methodology found in the CINDER(England, et al. 1970) computer code, was used to solve the equations associated with the natural production and decay processes in the tank. The results of this simulation will be used to determine the most prudent disposal/recovery options available.
Date: January 1, 1992
Creator: Trumble, E.F.
Partner: UNT Libraries Government Documents Department

Consequences of expansion joint bellows rupture

Description: Expansion joints are used in piping systems to accommodate pipe deflections during service and to facilitate fitup. Typically, the expansion joint bellows is the thinnest part of the pressure boundary, bellows rupture frequencies are typically several orders of magnitude higher than pipe rupture frequencies. This paper reviews an effort to estimate the flow rates associated with bellows rupture. The Level I PRA (probabilistic risk assessment) for the Savannah River Site production reactors made the bounding assumption that bellows rupture would produce the maximum possible leakage - that of a double-ended guillotine break (DEGB). This assumption resulted in predictions of flooding of the reactor building with a high conditional probability that a Loss of Pumping Accident and core melting would follow. This paper describes analyses that were performed to develop a realistic break area and leak rate resulting from bellows rupture and therefore reduce the impact that bellows rupture can have on the estimated total core melt frequency. In the event of a 360 degree circumferential break of the bellows the resulting two sections will separate to the point where the force from the internal pressure acting to push the bellows open is just balanced by the spring force of the bellows itself. For the bellows addressed in this analysis, the equilibrium separation distance is 0.7 inches with normal pump lineup. The opening area is influenced by any initial compression or extension due to installation alignment, and by any operational displacements such as thermal expansion of the adjoining pipe. The influence of such factors is considered and the impact on the flooding rate and, hence, core melt frequency is reviewed.
Date: January 1, 1992
Creator: Daugherty, W.L.; Miller, R.F. & Cramer, D.S.
Partner: UNT Libraries Government Documents Department

Failure of expansion joint tie rods -- Impact on bellows integrity

Description: Expansion joints are used in piping systems to accomodate pipe deflections during service and to facilitate fitup. Often, tie rods are employed to limit the range of axial deflection. Additional restraint against excessive displacement can be provided by the surrounding pipe and associated supports. This paper presents a methodology that was employed to estimate the consequences of tie rod failure. Of particular interest is whether tie rod failure can lead to sufficient displacement as to cause bellows rupture.
Date: January 1, 1992
Creator: Daugherty, W.L. & Miller, R.F.
Partner: UNT Libraries Government Documents Department

Failure strain and mechanical property data for the Type IIIA waste tank liners

Description: The SRS Waste Tanks at the Savannah River Site to be employed in the In-Tank Precipitation (ITP) process are undergoing a structural evaluation in order to define their response to a hypothetical deflagration accident. This report provides mechanical property data to support the structural analyses, and characterizes the impact of mechanical property variability and materials degradation on the failure strain of the primary liner.
Date: June 1, 1992
Creator: Thomas, J.K.
Partner: UNT Libraries Government Documents Department