Newsletter focusing on pecan disease and pest control in Texas, including prevention, identification, treatment, and educational opportunities.

Twelve weld overlay hardfacing alloys have been selected for preliminary erosion testing based on a literature review These alloys have been separated into three major groups: (1) Cobalt containing alloys, (2) Nickel-base alloys, (3) Iron base alloys. These alloys are being applied to carbon steel substrates and will undergo preliminary erosion testing to identify candidates weld overlay alloys for erosion control in CFB boilers. The candidate alloys selected from the preliminary erosion tests will then undergo more detailed evaluations in future research.

Concentration guidelines for residual radionuclides in soil at the sites of the Old F- and a Retention Basins (281-3F, 281-3H) have been calculated using a dose-based approach. The guidelines also are being applied to areas around the F-Basin`s Process Line. Estimation of these soil guidelines was completed using RESRAD 5.0 in accordance with the DOE RESRAD methodology specified in DOE/CH/8901 (Gi89). Guidelines are provided for the nuclides known to be present in the soils at each basin (Sc87). Soil and hydrologic characteristics specific to each basin are defined for the areas above, within, and beneath the contaminated zones.

This paper tests an approach to predict the range of ground motion hazard at specific sites generated by earthquakes on specific faults. The approach is based upon structural, lithological and rheological descriptions of the fault zones, development of fault rupture scenarios, and computation of synthetic seismograms using empirical Green`s functions. Faults are placed within a regional geomechanical model. The approach is based upon three hypothesis: (1) An exact solution of the representation relation that utilizes empirical Green`s functions enables very accurate computation of ground motions generated by a given rupture; (2) a general description of the rupture is sufficient; and (3) the structural, lithological and Theological characteristics of a fault can be used to constrain, in advance, possible future rupture histories. Ground motion hazard here refers to three-component, full wave train descriptions of displacement, velocity, and acceleration over the frequency band 0.01 to 25 Hz. Corollaries to these hypotheses are that the range of possible fault rupture histories is narrow enough to functionally constrain the range of strong ground motion predictions, and that a discreet set of rupture histories is sufficient to span the infinite combinations possible from a given range of rupture parameters.

This description of work details field activities associated with drilling four boreholes in the 100-HR-3 Operable Unit for placement of four In Situ Permeable Flow Sensors near the 183-H Basin. A sonic drill rig funded under a Cooperative Research and Development Agreement (CRADA) will be employed to drill the boreholes. This project includes installation of automatic data logging and telemetry equipment. Each Sensor will be supplied with a data logger at the surface which will be wired to a cellular phone on site or to an existing telemetry station to transmit data to a computer in 2440 Stevens Center. Power to operate the Sensors and data loggers will be supplied by a small gasoline or diesel generator. Processed data will be used to develop a three-dimensional flownet of the unconfined aquifer near and within the Columbia River influenced mixing zone.

We are currently performing a series of pilot-scale tests designed to determine the effects that adsorbed water has on fabric filtration and electrostatic precipitation of entrained fly ash particles in actual flue gas environments. We are investigating two key phenomena in our pilot-scale tests. The first is the ability of flue gas humidification to increase ash cohesivity through the creation of liquid bridges between particles collected in a fabric filter. Increasing cohesivity through the development of liquid bridges was demonstrated in our laboratory measurements of tensile strength and uncompacted bulk porosity, and in filtration studies performed for DOE/PETC under an earlier contract. With the range of coals that will be fired in Southern Research Institute`s Coal Combustion Facility (CCF), filtration tests should verify how different fly ashes react to water conditioning in actual flue gas environments. The CCF provides a valuable test location for our studies. The second phenomenon we plan to study is the electrostatic reentrainment of previously collected ash particles in an ESP. We have prepared a small ESP for use in our pilot-scale tests. Our laboratory studies have shown the effects that relative humidity can have on the forces that hold the collected ash on the grounded …

Concentration guidelines for residual radionuclides in soil at the sites of the Old F- and H-Area Retention Basins (281-3F, 281-3H) have been calculated using a dose-based approach. The guidelines also are being applied to areas around the F-Basin`s Process Line. Estimation of these soil guidelines was completed using RESRAD 5.0 in accordance with the DOE RESRAD methodology specified in DOE/CH/8901 (Gi89). Guidelines are provided for the nuclides known to be present in the soils at each basin (Sc87). Soil and hydrologic characteristics specific to each basin are defined for the areas above, within, and beneath the contaminated zones.

In this research program, a laboratory test facility was built for the purpose of testing a gas-fired water heating appliance. This test facility can be used to examine the important performance characteristics of efficiency, dynamic response, and quality of combustion. An innovative design for a tankless water heater was built and then tested to determine its performance characteristics. This unit was tested over a 5:1 range in input (20,000 to 100,000 btuh heat input). The unit was then configured as a circulating hot water boiler, and a specially designed heat exchanger was used with it to generate domestic hot water. This unit was also tested, and was found to offer performance advantages with regard to low flow and temperature stability.

A meeting was held on October 15, 16, 17, 1990 to discuss the state of tritium safety and environmental effects. The meeting was organized with the help of the International Energy Agency planning committee consisting of K. Steinmetz, Y. Seki, G. Nardella, and G. Vivian. Representative of tritium production facilities and heavy water reactor power production were also involved. The meeting was organized to address seven topics in tritium safety that were thought to require further work. The topics were: (1) materials science, (2) environmental models, (3) environmental model validation, (4) tritiated organic compounds, (5) human dosimetry, (6) tritium sampling and measurement, and (7) long-term environmental databases.

The use of foam in decontamination operations offers significant reductions in waste generation. Initial use has confirmed its effectiveness. Issues being resolved at Savannah River Site (SRS) include compatibility of foam generating solutions with decontamination solutions, waste disposal, and operational safety.

Newsletter of the Texas Bureau of Disease Control and Epidemiology discussing the news, activities, and events of the organization and other information related to health in Texas.

In this research program, a laboratory test facility was built for the purpose of testing a gas-fired water heating appliance. This test facility can be used to examine the important performance characteristics of efficiency, dynamic response, and quality of combustion. An innovative design for a tankless water heater was built and then tested to determine its performance characteristics. This unit was tested over a 5:1 range in input (20,000 to 100,000 btuh heat input). The unit was then configured as a circulating hot water boiler, and a specially designed heat exchanger was used with it to generate domestic hot water. This unit was also tested, and was found to offer performance advantages with regard to low flow and temperature stability.

Experiments are currently in progress testing the optical quality of cryogenic targets made using the {beta}-layering process. This process uses the heat liberated from decaying tritium to sublimate thick parts of the DT layer. This sublimated DT is subsequently condensed on a thinner part of the shell thereby tending to equalize the layer thickness. The uniformity and stability of the ice layer formed on the inside of these capsules is of fundamental importance. The experiments now being performed simply photograph a capsule through a pair of transparent windows in the dewar as the temperature is lowered below the triple point and finally the sublimation point of the DT mixture. The analysis of these photographs is made difficult by the strong refraction and multiple reflections of the light by the sapphire shell and the relatively weak refraction at the vacuum solid DT interface. Photographs thus far obtained show very little difference between an empty shell and a shell which is believed to be uniformly layered with hydrogen ice. The difficulty in interpreting these data has led to the establishment of an effort to simulate these measurements by direct computational methods. The code which is the subject of this report is a …

Twelve weld overlay hardfacing alloys have been selected for preliminary erosion testing based on a literature review These alloys have been separated into three major groups: (1) Cobalt containing alloys, (2) Nickel-base alloys, (3) Iron base alloys. These alloys are being applied to carbon steel substrates and will undergo preliminary erosion testing to identify candidates weld overlay alloys for erosion control in CFB boilers. The candidate alloys selected from the preliminary erosion tests will then undergo more detailed evaluations in future research.

A meeting was held on October 15, 16, 17, 1990 to discuss the state of tritium safety and environmental effects. The meeting was organized with the help of the International Energy Agency planning committee consisting of K. Steinmetz, Y. Seki, G. Nardella, and G. Vivian. Representative of tritium production facilities and heavy water reactor power production were also involved. The meeting was organized to address seven topics in tritium safety that were thought to require further work. The topics were: (1) materials science, (2) environmental models, (3) environmental model validation, (4) tritiated organic compounds, (5) human dosimetry, (6) tritium sampling and measurement, and (7) long-term environmental databases.

The use of foam in decontamination operations offers significant reductions in waste generation. Initial use has confirmed its effectiveness. Issues being resolved at Savannah River Site (SRS) include compatibility of foam generating solutions with decontamination solutions, waste disposal, and operational safety.

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Research continued on task 2, the measurements on carbides with the fluorite structure. There are twelve known carbides of the fluorite structure with transition temperatures from 350-1450 C. Small quantities of these carbides in powder form will be purchased when commercially available. Pellets pressed from powder within an inert atmosphere will be made, CVI treated, and tested as described in Task No. 1. Pure carbides will be tested first, followed by carbides doped with impurities of different electrical valences whose atomic radii are favorable for solubility in the carbide lattice structure. Dopants will be introduced either during the chemical formation of the carbide, by mix and sinter diffusion, or by high energy ion bombardment of the powder prior to pelletization. The approximate time period for completion of Task No. 2 is twelve months. Investigations have been hampered by equipment failures. Progress is described.

The integrated system that embraces forest management, forest products, and land-use change impacts the global carbon cycle - and hence the net emission of the greenhouse gas carbon dioxide - in four fundamental ways. Carbon is stored in living and dead biomass, carbon is stored in wood products and landfills, forest products substitute in the market place for products made from other materials, and forest harvests can be used wholly or partially to displace fossil fuels in the energy sector. Implementation of the Kyoto Protocol to the United Nations Framework Convention on Climate Change would result in the creation of international markets for carbon dioxide emissions credits, but the current Kyoto text does not treat all carbon identically. We have developed a carbon accounting model, GORCAM, to examine a variety of scenarios for land management and the production of forest products. In this paper we explore, for two simple scenarios of forest management, the carbon flows that occur and how these might be accounted for under the Kyoto text. The Kyoto protocol raises questions about what activities can result in emissions credits, which carbon reservoirs will be counted, who will receive the credits, and how much credit will be available? …