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This reporting period covers the first half of the two-year sub-task, which includes a review of recent and ongoing engineering studies concerning practical modes for the ocean discharge of CO{sub 2}, review of recent and ongoing experimental studies concerning the rates (and extent) of formation and dissolution for CO{sub 2} hydrates, review of recent and ongoing biological studies concerning organism response to reduced pH and increased CO{sub 2} concentration, and the definition of discharge scenarios. These steps have been successfully completed. Results-to-date were presented at the Annual Fall Meeting of AGU (December 2005) and will be presented at the Annual DOE Meeting on Carbon Capture and Sequestration (May, 2006). The objective during this reporting period was to begin a two-year sub-task to update an assessment of environmental impacts from direct ocean sequestration. The approach is based on the work of Auerbach et al. (1997) and Caulfield et al. (1997) to assess acute impacts, but uses updated information concerning injection scenarios and bioassays.

This report gives progress made on the following milestones: demonstrate Ti and Nb monitoring at 3M site, demonstrate Al monitoring at LLNL, complete baseline melt and vapor plume model for the metal matrix process (3M fiber coating process), prototype a laser at LLNL to monitor Cu, ZrO{sub 2} monitoring demonstration at LLNL, Se monitoring demonstration, and process scale-up study for YBCO high-temperature superconductor.

This report documents the Environmental Transport Section's (ETS) two-dimensional, sequential gaussian puff transport and dispersion model for emergency response. The sequential puff scheme is described, and the dispersion equations are presented. The advantages of this model over the ETS's PUFF/PLUME model are discussed. Options are calculating a two-dimensional wind field, interpolation procedures, and the wind field grid are described. The various grid systems for puff transport calculations and dose estimates are also described. A flow diagram for the modules comprising the 2DPUF code and a description of each module is presented.

The EPRI Plume Model Validation Project (PMV) is a continuing effort designed to provide the data bases and analyses for rigorous operational and scientific validation of plume models. In this project the behavior and fate of buoyant plumes emitted from tall stacks are the foci of attention. To date, a network of 200 tracer samplers, 30 air quality samplers, two aircraft, two remote plume sensing devices, and a full complement of upper air and surface meteorological sensors have been used to acquire data on plume behavior and ground-level concentrations in the vicinity of an isolated power plant located in the plains of central Illinois. Similar or even more extensive measurements are planned for hilly and mountainous terrain conditions when the work at the plains' site is completed. The present report is intended as an interim and partial presentation of the first operational plume model validations completed under the PMV Project. Four Gaussian models commonly used for operational and regulatory purposes have been tested against measured ground-level plume concentrations acquired during the 1980 Spring and Summer seasons at the plains sites. Objective validation protocols and statistical methodologies developed for PMV have been employed in these tests of model performance. The resultsmore » of these interim validation tests are described in this report.« less

When the atmospheric diffusion of a material is described by the usual Guysian plume model, dry deposition of the contaminant onto the underlying surface is commonly accounted for by appropriately reducing the source strength, as originally proposed by Chamberlain. A more realistic model is developed which selectively depletes the Gaussian plume in the vicinity of the deposition surface rather than throughout the vertical extent of the plume as done in the source depletion model. This improved model is used to show that the source depletion model consistently overpredicts the surface air concentration and the deposition at downwind locations close to the source and, as a consequence, is biased in the opposite sense for locations far from the source. At all distances from the source, the source depletion model overestimates the total deposition between source and receptor and consequently underpredicts the amount of remaining airborne material. Quantitative comparisons are shown to aid the user in choosing, for his particular circumstances, between the less accurate source depletion model and the computationally more complex surface depletion model. Dry deposition of an airborne material onto the un- derlying surface is of interest from two different stand- points. First of all, it can be an important sink for the material, reducing air concentrations (and conse- quent dry deposition) further downwind. In the case of a noxious substance this is beneficial to downwind receptors. However, dry deposition secondly is a mechanism for accumulation of the material on the ground and hence may be detrimental at the point of deposition. Since a high estimate for the deposition flux will be conservative at the point of deposition and, at the same time, nonconservative downwind of that point, modeling of the dry deposition process should be unbiased. However, it will be shown here that the source depletion model currently used for predicting deposition from the Gaussian plume is biased. This will be done by developing a surface dep- letion model which eliminates the artificial bias of the former model and by comparing the predictions of the two models. The biases of the source depletion model will be quantitatively delineated in order to provide a basis for choosing, in a specific situation, between the less accurate source depletion model and the computationally more complex surface depletion model.

This report is a catalog of existing air quality data bases that could be used in plume model validation studies. The information was compiled through the use of questionnaires and direct discussions with the air quality specialists in industry, government agencies, and private consulting companies. This report is intended to be used as a reference to locate and acquire data bases for future plume model validation studies.

One part representing work on the development and testing of a flowmeter for measuring the motion of solids in a fluidized bed and the second part (a Ph. D. Thesis) on the plume model of fluidized-bed combustion of coal, including its development and validation, have been entered individually into EDB and ERA. (LTN)