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An evaluation of retention and disposal options for tritium in fuel reprocessing

Description: This report assesses the possible options for retention of tritium and its ultimate disposal during future reprocessing of irradiated oxide fuels discharged from light water reactors (LWRs) and liquid metal fast breeder reactors (LMFBRs). The assessment includes an appraisal of the state of the retention and disposal options, an estimate of the dose commitments to the general public, an estimation of the incremental costs of the several retention and disposal options, and the potential reduction of the dose commitments resulting from retention and disposal of the tritium. The assessment is based upon an extensive study of tritium retention in reprocessing completed in 1982 by Grimes et al. Two plants were assumed, one to process LWR oxide fuel and the other to process LMFBR fuel. In each base case plant the tritium was vaporized to the atmosphere. Each of the hypothetical plants was assumed to be constructed during the 1990`s and to operate for a 20-year lifetime beginning in the year 2000 at a rate of 1,500 metric tons of heavy metal (MTHM) per 300-d year. In addition to the base case (Case 1), six other cases which included tritium retention options were examined. Although many of the features of the base-case plants remain unchanged in the tritium retention options, each case requires some additions, deletions, and modifications of portions of the plants. The retained tritium must also be managed and disposed of in a manner that is environmentally acceptable.
Date: 1987-21~
Creator: Benjamin, R. W. & Hampson, D. C.
Partner: UNT Libraries Government Documents Department

Autecology of Vibrio vulnificus and Vibrio parahaemolyticus in tropical waters

Description: Water and shellfish samples collected from estuaries, mangroves, and beaches along the coast of Puerto Rico were examined for Vibrio vulnificus and Vibrio parahaemolyticus. An array of water quality parameters were also measured simultaneous with bacteria sampling. Both species of vibrio were associated with estuary and mangrove locations, and neither was isolated from sandy beaches. Densities of V. vulnificus were negatively correlated with salinity, 10--15 ppt being optimal. V. parahaemolyticus was isolated from sites with salinities between 20 and 35 ppt, the highest densities occurring at 20 ppt. Densities of Vibrio spp. and V. parahaemolyticus for a tropical estuary surpassed those reported for temperate estuaries by several orders of magnitude. Both densities of total Vibrio spp. and V. parahaemolyticus in the water were directly related to densities of fecal coliforms, unlike V. vulnificus. The incidence of ONPG(+) strains among sucrose({minus}) Vibrio spp. served as an indicator of the frequency of V. vulnificus in this group. More than 63% of the V. vulnificus isolated were pathogenic. V. vulnificus and V. parahaemolyticus occupy clearly separate niches within the tropical estuarine-marine ecosystem.
Date: Spring 1988
Creator: Rivera, S.; Lugo, T. & Hazen, T. C.
Partner: UNT Libraries Government Documents Department

Legionella in Puerto Rico cooling towers

Description: Water samples from air conditioning cooling towers receiving different treatment protocols on five large municipal buildings in San Juan, Puerto Rico were assayed for various species and serogroups of Legionella spp. using direct immunofluorescence. Several water quality parameters were also measured with each sample. Guinea pigs were inoculated with water samples to confirm pathogenicity and recover viable organisms. Legionella pneumophila (1-6), L. bozemanii, L. micdadei, L. dumoffii, and L. gormanii were observed in at least one of the cooling towers. L. pneumophila was the most abundant species, reaching 10{sup 5} cells/ml, within the range that is considered potentially pathogenic to humans. A significantly higher density of L. pneumophila was observed in the cooling tower water that was not being treated with biocides. Percent respiration (INT) and total cell activity (AODC), were inversely correlated with bacterial density. This study demonstrates that Legionella spp. are present in tropical air-conditioning cooling systems, and without continuous biocide treatment may reach densities that present a health risk.
Date: Spring 1988
Creator: Negron-Alviro, A.; Perez-Suarez, I. & Hazen, T. C.
Partner: UNT Libraries Government Documents Department

Enteric viruses in a mangrove lagoon, survival and shellfish incidence

Description: Mangrove oysters (Crassostrea rhizophorae) were screened for enteric viruses. For 18 months oysters were collected from Cano Boqueron, a tropical mangrove lagoon on the southwest coast of Puerto Rico. This popular tourist resort has two primary sewage treatment plants which service 158 single family cabanas. In spite of the heavy seasonal input of sewage to Cano Boqueron and high densities of fecal coliform bacteria, enteric viruses were not detected in shellfish meat. Because no viruses were detected in the oysters, a virus survival study was performed. Poliovirus type 1 was placed in diffusion chambers in situ at two sites in Cano Boqueron. More than 95% of the poliovirus inactivation occurred within 24 h. Virus inactivation was significantly different by site, indicating different inactivation rates within the lagoon. Chamber studies done simultaneously with Escherichia coli did not reveal differences between sites. It is suggested that the sewage effluent had an antiviral effect in the absence of an antibacterial effect. This study demonstrates the importance for establishing microbial contamination standards for shellfish growing waters in the tropics based upon in situ studies with tropical species, e.g. mangrove oyster.
Date: Spring 1988
Creator: Lopez de Cardona, I.; Bermudez, M.; Billmire, E. & Hazen, T. C.
Partner: UNT Libraries Government Documents Department

Sensitivity of SRP LOCA power limit to break size and location

Description: SRP reactors are low pressure, heavy water reactors with six external process water loops that drive the coolant into an upper plenum and then downward through the assemblies. Assembly LOCA power limits are currently set in these reactors to prevent Ledinegg flow instability (FI) in any assembly flow channel. These limits are based on a postulated break area and location. This study determined the sensitivity of the power limit to the break area and location.
Date: 1989-06~
Creator: White, A. M.; Pevey, R. E. & Smith, F. G.
Partner: UNT Libraries Government Documents Department

The organization and operation of the Savannah River Plant`s groundwater monitoring program. Revision 3

Description: The Savannah River Plant (SRP) is operated by Du Pont for the Department of Energy. The plant has been operating since 1952 and is one of the largest industrial facilities in the nation. Its function is to produce nuclear materials for the national defense. This paper describes the organization and operation of the Groundwater Monitoring Program (GMP) at the SRP. Groundwater has been actively monitored for radiological parameters at the SRP since the commencement of site operations in the 1950s. More recently, monitoring expanded to include chemical parameters and numerous additional facilities. The GMP is a large monitoring program. Over 700 wells monitor more than 70 facilities which are spread over 300 square miles. The program includes both Du Pont personnel and contractors and is responsible for all phases of groundwater monitoring: the installation (or abandonment) of monitoring wells, the determination of water quality (sample collection, analysis, data review, etc.), and the generation of reports.
Date: September 1988
Creator: Olson, C. M. & Heffner, J. D.
Partner: UNT Libraries Government Documents Department

Data acquisition with Masscomp

Description: Applications and products for data acquisition and control are abundant. Systems and boards for Apple or IBM products collect, store, and manipulate data up to rates in the 10`s of thousands. These systems may suit your application; if so, it would be good for you to obtain one of these systems. However, if you need speed in the hundreds of thousands of samples per second and you want to store, process, and display data in real time, data acquisition becomes much more complex. Operating system code has to be sufficient to handle the load. A company known as Massachusetts Computer Corporation has modified UNIX operating system code to allow real time data acquisition and control. They call this operating system Real Time Unix, or RTU. They have built a family of computer systems around this operating system with specialized hardware to handle multiple processes and quick communications, which a real time operating system needs to function. This paper covers the basics of an application using a Masscomp 5520 computer. The application is for the KYLE Project Cold Tests in SRL. KYLE is a classified weapons program. The data flow from source to Masscomp, the generic features of Masscomp systems, and the specifics of the Masscomp computer related to this application will be presented.
Date: October 1988
Creator: Collins, A. J.
Partner: UNT Libraries Government Documents Department

Evaluation of automated emergency response systems

Description: Automated Emergency Response (ER) systems are playing a greater role in providing prompt and reliable predictions of the impact of inadvertent releases of hazardous materials to the environment. Observed and forecast environmental and accident source term data are input into environmental transport and dispersion models to provide dosimetry estimates used as decision making aids for responding to emergencies. Several automated ER systems have been developed for US Federal Government facilities and many are available commercially. For such systems to be useful, they must reliably and consistently deliver a timely product to the decision makers. Evaluation of the entire ER system is essential to determine the performance that can be expected from the system during an emergency. Unfortunately, seldom are ER systems evaluated as a whole. Usually Quality Assurance programs evaluate the performance of individual components of the system. Most atmospheric pollution model evaluation methods usually involve an evaluation of the predictive performance of the transport and dispersion model when compared either with experimental tracer results or results from other models. Rarely, however, is the ability of the ER system to provide timely, reliable and consistent information evaluated. Such an evaluation is vital to determine the system performance during an emergency and to provide valuable information to aid in improving the system.
Date: 1988-09~
Creator: Addis, R. P.
Partner: UNT Libraries Government Documents Department

Analysis of the anomalous scale-dependent behavior of dispersivity using straightforward analytical equations: Flow variance vs. dispersion

Description: Recent field and laboratory data have confirmed that apparent dispersivity is a function of the flow distance of the measurement. This scale effect is not consistent with classical advection dispersion modeling often used to describe the transport of solutes in saturated porous media. Many investigators attribute this anomalous behavior to the fact that the spreading of solute is actually the result of the heterogeneity of subsurface materials and the wide distribution of flow paths and velocities available in such systems. An analysis using straightforward analytical equations confirms this hypothesis. An analytical equation based on a flow variance approach matches available field data when a variance description of approximately 0.4 is employed. Also, current field data provide a basis for statistical selection of the variance parameter based on the level of concern related to the resulting calculated concentration. While the advection dispersion approach often yielded reasonable predictions, continued development of statistical and stochastic techniques will provide more defendable and mechanistically descriptive models.
Date: Spring 1988
Creator: Looney, B. B. & Scott, M. T.
Partner: UNT Libraries Government Documents Department

Mitigation alternatives for L Lake

Description: The current condition of L Lake/Steel Creek was summarized in a report to SCDHEC in June 1988 which reported that the L Lake and Steel Creek ecosystems were adequately developing towards balanced biological communities. If mitigation for L Lake inputs, specifically temperature and nutrients, are required, several viable alternatives are available. A report prepared by Spencer in 1986 discusses the various options available for cooling L-Reactor discharges. In effect, a small cooling tower is the only realistic solution to reducing effluent temperatures. Nutrient mitigation can take several approaches including upstream sewage treatment, hypolimnetic withdrawal, dilution of input water by Par Pond water, precipitation of nutrients, and sediment oxidation. None of these systems would influence the thermal regime, but would significantly reduce nutrient input into the system. One beneficial use of L-Lake thermal effluents is algaculture, the production of useful algae. A document prepared in 1988 concludes that algaculture is a technically and economically feasible mitigation alternative for L Lake and could allow L Lake to be handled under Section 318 of the Clean Water Act.
Date: November 3, 1988
Creator: Moore, D. B.
Partner: UNT Libraries Government Documents Department

Monitoring system for unplanned releases at the Savannah River Plant

Description: The monitoring system for unplanned releases at the Savannah River Plant (SRP) consists of separation facilities stack monitors, production reactor filter compartment and stack monitors, 12 site perimeter monitors, the NOAA-Geostationary Operational Environmental Satellite (GOES) data link, meteorological tower system, Weather Information and Display (WIND) system computer, and the VANTAGE database management system. The unplanned release monitoring system provides automatic monitoring of abnormal stack releases and automatic inclusion of these in the WIND system emergency response codes.
Date: Spring 1988
Creator: Schubert, J. F.
Partner: UNT Libraries Government Documents Department

Making and suspension capabilities of vibratory agitators in a slab tank

Description: Seven different vibratory agitators, consisting of single and dual flat blade configurations or dual angle blade configurations, were studied for their ability to produce mixing and solid suspension in a slab tank. The mixing behavior of the various configurations was recorded on video tape, and mixing times were measured as the time needed to disperse injected dye. The solid suspension tests, using ash tray sand, were conducted to determine the minimum stroke frequency of the agitators needed for complete off-bottom suspension. The mixing studies demonstrated that vibratory agitation produced strong vertical fluid motion, good bulk circulation and dispersion in the liquid. The effects of stroke frequency, n; amplitude, a; blade width, w; blade clearance, c; and liquid depth, h, on mixing time, {theta}, were studied. Single blade geometries produced complete mixing in the least number of strokes. The most effective geometry, in terms of both mixing and solid suspension, was a single flat blade with minimum off-bottom clearance and a blade width/tank thickness ratio, w/T, of 0.74 at the maximum stroke amplitude of 51 mm.
Date: Spring 1988
Creator: Ramsey, C. J.; Kyser, E. A., III & Tatterson, G. B.
Partner: UNT Libraries Government Documents Department

Survival and activity of Streptococcus faecalis and Escherichia coli in tropical freshwater

Description: The survival of Streptococcus facecalis and Escherichia coli was studied in situ in a tropical rain forest watershed using membrane diffusion chambers. Densities were determined by acridine orange direct count and Coulter Counter. Population activity was determined by microautoradiography, cell respiration, and by nucleic acid composition. Densities of S. facecalis and E. coli decreased less than 1 log unit after 105 h as measured by direct count methods. Activity as measured by respiration, acridine orange activity, and microautoradiography indicated that both bacteria remained moderately active during the entire study. After 12 h, E. coli was more active than S. faecalis as measured by nucleic acid composition. E. coli and S. faecalis survived and remained active for more than 5 days. Consequently, both would seem to be unsuitable as indicators of recent fecal contamination in tropical waters.
Date: Spring 1988
Creator: Muniz, I.; Jimenez, L.; Toranzos, G. A. & Hazen, T. C.
Partner: UNT Libraries Government Documents Department

Survival and distribution of Vibrio cholerae in a tropical rain forest stream

Description: For 12 months Vibrio cholerae and fecal coliforms were monitored along with 9 other water quality parameters at 12 sites in a rain forest watershed in Puerto Rico. Densities of V. cholerae and fecal coliforms were not significantly correlated even though the highest densities of both bacteria were found at a sewage outfall. High densities of V. cholerae were also found at pristine sites high in the watershed. V. cholerae and Escherichia coli were inoculated into membrane diffusion chambers, placed at two sites and monitored for 5 days on two different occasions. Two different direct count methods indicated that the density of E. coli and V. cholerae did not change significantly during the course of either study. Physiological activity, as measured by INT-reduction and relative nucleic acid composition declined for E. coli during the first 12 h then increased and remained variable during the remainder of the study. V. cholerae activity, as measured by relative nucleic acid concentrations, remained high and unchanged for the entire study. INT-reduction in V. cholerae declined initially but regained nearly all of it`s original activity within 48 h. This study suggests that V. cholerae is an indigenous organism in tropical freshwaters and that assays other than fecal coliforms or E. coli must be used for assessing public health risk in tropical waters.
Date: Spring 1988
Creator: Perez-Rosas, N. & Hazen, T. C.
Partner: UNT Libraries Government Documents Department

Multiple antibiotic resistant Escherichia coli from a tropical rain forest stream

Description: High densities of fecal coliforms were obtained from a pristine site and sewage contaminated site in a tropical rain forest watershed in Puerto Rico. Confirmation of fecal coliform isolates as Escherichia coli was significantly lower than for temperate waters. Antibiotic resistance and multiple antibiotic resistance were common for isolates at both sites; however, the site receiving sewage effluent had a greater proportion of multiple antibiotic resistant isolates. R. plasmids were recovered from 4 MAR isolates, 2 from each site. All recovered plasmids were approximately 1 kilobase. The recovered plasmid were also capable of transforming E. coli HB101 in vitro. The high concentrations of enterobacteriaceae, small R-plasmid size, R-plasmid transformability, and long term survival of fecal origin bacteria in tropical freshwater environments give increasing importance to adequate sewage treatment, and better indicator monitoring methods for tropical areas.
Date: Spring 1988
Creator: Carrasco, C. E.; Alvarez, H. J.; Ortiz, N.; Bisbal, M.; Arias, W.; Baerga, C. et al.
Partner: UNT Libraries Government Documents Department

Survival and activity of Streptococcus faecalis and Escherichia coli in petroleum-contaminated tropical marine waters

Description: The in situ survival and activity of Streptococcus faecalis and Escherichia coli were studied using membrane diffusion chambers in tropical marine waters receiving oil refinery effluents. Protein synthesis, DNA synthesis, respiration or fermentation, INT reduced per cell, and ATP per cell were used to measure physiological activity. Cell densities decreased significantly over time at both sites for both S. faecalis and E. coli; however, no significant differences in survival pattern were observed between S. faecalis and E.coli. Differences in protein synthesis between the two were only observed at a study site which was not heavily oiled. Although fecal streptococci have been suggested as a better indicator of fecal contamination than fecal coliforms in marine waters, in this study both E. coli and S. faecalis survived and remained physiologically active for extended periods of time. These results suggest that the fecal streptococci group is not a better indicator of fecal contamination in tropical marine waters than the fecal coliform group, especially when that environment is high in long-chained hydrocarbons.
Date: Spring 1987
Creator: Santo Domingo, J. W.; Fuentes, F. A. & Hazen, T. C.
Partner: UNT Libraries Government Documents Department

Measurement of the deposition and fate of {sup 35}SO{sub 2} in a pine plantation

Description: An experiment was carried out to determine the uptake rate and fate of SO{sub 2} absorbed by the forest canopy. The radioactive tracer, {sup 35}S was used. Branches of loblolly pine were exposed to {sup 35}SO{sub 2} in the field with a portable chamber. The exposed branches were excised and a sample of needles was immediately washed with distilled water. The needles and water collected in the field was analyzed for {sup 35}S content. The results indicated that a portion of the {sup 35}S could be washed from the needles and another portion was not removed with a water rinse. The portion that could not be removed by rinsing was absorbed at a rate, and followed patterns of absorption, that suggested that absorption was controlled by stomatal diffusion, and thus was internal. The {sup 35}S that could be removed by rinsing appeared to be surface absorption.
Date: Spring 1988
Creator: Gay, D. W. & Murphy, C. E., Jr.
Partner: UNT Libraries Government Documents Department

Proper statistical treatment of species-area data

Description: The purpose of this report is to comment on the entire process of analyzing species-area data, particularly as performed by Rydin and Borgegaard (1988). They use three different models to test species-area relations for islands over a 100 year period. Several aspects of their analysis of species-area data could be improved, including their comparison of goodness-of-fit and testing of the expected value of z. The reason that these issues are important (their basic conclusions being correct) is that there is acrimonious debate over the best model to use for species-area curves and over whether the scope coefficient is constant or is an artifact, and because the species-area curve is being used for nature reserve design. The problems pointed out here are common to a large class of allometric-type analyses in ecology. The author attempts to show the potential pitfalls inherent in allometric analyses and demonstrate methods for avoiding these problems.
Date: Spring 1988
Creator: Loehle, C.
Partner: UNT Libraries Government Documents Department

Measurements of iodine uptake in falling water droplets

Description: The removal of gaseous iodine from air by water sprays was measured, using both ordinary water and a solution buffered to a pH near 9.5 with a carbonate mixture. The results were compared to the theoretical predictions of the I2WASH computer code. In all experiments, using both large and small spray droplets, the solution at the higher pH was approximately three times as effective at absorbing iodine from the air. This agrees with the predictions of the computer model for the smaller droplets studied. The computer code predicts no pH effect for large drops, probably because it assumes a well-mixed drop, and mixing during the fall time is too slow.
Date: 1989
Creator: Hyder, M. L.
Partner: UNT Libraries Government Documents Department

Electrocatalytic reduction of nitrate and nitrite at Nafion-coated electrodes in concentrated sodium hydroxide solution

Description: The electrochemical reduction of nitrate ions in alkaline solution has been studied using various cathode materials and is the basis for a patent describing the conversion of nitrate into hydroxide ion in carbonate solutions. Recently, Taniguchi et al. have reported that certain well studied transition metal cyclic amine complexes, namely Co(III)-cyclam and Ni(II)-cyclam where cyclam is 1,4,8,11-tetraazacyclotetradecane, efficiently electrocatalyze the reduction of nitrate and nitrite to hydroxylamine at mercury electrodes. Here the authors report that the metal cyclam catalyst can be incorporated into a Nafion film electrode, and that the reduction of nitrate and nitrite proceeds efficiently at these electrodes in concentrated NaOH solution. Nafion is a perfluoroalkanesulfonated cation exchange material that has been widely used to immobilize redox couples at electrode surfaces, including electrocatalysis species.
Date: Spring 1988
Creator: Li, H.; Chambers, J. Q. & Hobbs, D. T.
Partner: UNT Libraries Government Documents Department

Microbial life in the deep terrestrial subsurface

Description: The distribution and function of microorganisms is a vital issue in microbial ecology. The US Department of Energy`s Program, ``Microbiology of the Deep Subsurface,`` concentrates on establishing fundamental scientific information about organisms at depth, and the use of these organisms for remediation of contaminants in deep vadose zone and groundwater environments. This investigation effectively extends the Biosphere hundreds of meters into the Geosphere and has implications to a variety of subsurface activities.
Date: Spring 1988
Creator: Fliermans, Carl B.; Balkwill, David L.; Beeman, Ralph E.; Bledsoe, Horace W.; Bollag, Jean-Marc; Corey, Jack C. et al.
Partner: UNT Libraries Government Documents Department

Testing and benchmarking of a three-dimensional groundwater flow and solute transport model

Description: A three-dimensional finite-difference model was developed to simulate groundwater flow and solute transport. The model is intended for application to a variety of groundwater resource and solute migration evaluations, including several complex sites at the Savannah River Plant (SRP). Because the model, FTWORK, is relatively new, there is a need to provide confidence in the model results. Methodologies that test models include comparisons with analytical solutions, comparisons with empirical data, and checking that conservation properties hold. Another level of testing is the comparison of one code against another. This paper describes the testing and benchmarking procedure used to verify the validate FTWORK.
Date: 1988
Creator: Sims, P. N.; Andersen, P. F.; Faust, C. R. & Stephenson, D. E.
Partner: UNT Libraries Government Documents Department

Life that really is down under

Description: The story begins in the early 1980`s, when it was recognized that fundamental science about deep aquifers (greater than 30 feet below the surface) was virtually non existent. If population centers were to continue to expand, the understanding of these deep reservoirs of life-giving water was essential. Over 53% of the US population receives its drinking water from wells, yet these sources continue to be polluted by government, industrial and private sources. If microorganism, life too small to be seen except through powerful microscopes, were present underground, then maybe they could help return polluted groundwaters to wholesome quality. Such was the vision in the Office of Health and Environmental Research at DOE that spawned the Microbiology of the Deep Subsurface Program.
Date: Spring 1988
Creator: Fliermans, C.
Partner: UNT Libraries Government Documents Department

Mineralization of trichloroethylene by heterotrophic enrichment cultures

Description: Microbial consortia capable of aerobically degrading greater than 99% of 50 mg/l exogenous trichloroethylene (TCE) have been enriched from TCE contaminated subsurface sediments. Concentrations of TCE greater than 300 mg/l were not degraded nor was TCE used as a sole energy source. Successful electron donors for growth included tryptone-yeast extract, methanol, methane or propane. The optimum temperature for growth was 22--37 C and the ph optimum was 7.0--8.1. Utilization of TCE occurred only after apparent microbial growth had ceased. The major end products recovered were hydrochloric acid and carbon dioxide. Minor products included dichloroethylene, vinylidine chloride and possibly chloroform.
Date: Spring 1988
Creator: Phelps, T. J.; Ringelberg, D.; Mikell, A. T.; White, D. C. & Fliermans, C. B.
Partner: UNT Libraries Government Documents Department