This report presents the f i r s t iteration of the Composite Analysis for Low-Level Wmte Disposal in the 200 Area Plateau of the Hmford Site (Composite Analysis) prepared in response to the U.S. Department of Energy Implementation Plan for the Defense Nuclear Facility Safety Board Recommendation 94-2. The Composite Analysis is a companion document to published analyses of four active or planned lowlevel waste disposal actions: the solid waste burial grounds in the 200 West Area, the solid waste burial grounds in the 200 East Area, the Environmental Restoration Disposal Facility, and the disposal facilities for immobilized lowractivity waste. A single Composite Analysis was prepared for the W o r d Site considering only sources on the 200 Area Plateau. The performance objectives prescribed in U.S. Department of Energy guidance for the Composite Analysis were 100 mrem in a year and examination of a lower dose (30 mrem in a year) to ensure the "as low as reasonably achievableyy concept is followed. The 100 mrem in a year limit was the maximum allowable all-pathways dose for 1000 years following Hanford Site closure, which is assumed to occur in 2050. These performance objectives apply to an accessible environment defined as the area between a buffer zone surrounding an exclusive waste management area on the 200 Area Plateau, and the Columbia River.Estimating doses to hypothetical future members of the public for the Composite Analysis was a multistep process involving the estimation or simulation of inventories; waste release to the environment; migration through the vadose zone, groundwater, and atmospheric pathways; and exposure and dose. Doses were estimated for scenarios based on agriculture, residential, industrial, and recreational land use.The radionuclides included in the vadose zone and groundwater pathway analyses of future releases were carbon-14, chlorine-36, selenium-79, technetium-99, iodine-129, and uranium isotopes. In addition, tritium and strontium-90 were included because they exist in groundwater plumes. Radionuclides considered in the atmospheric pathway included tritium and carbon-14.Most of the radionuclide inventory in past-practice liquid discharge and solid waste burial sites on the 200 Area Plateau was projected to be released in the f i r s t several hundred years following H d o r d Site closure and a significant fraction of the inventory was projected to be released prior to closure. The maximum predicted agricultural dose outside the buffer zone was less than 6 mrem in a year in 2050 and declined thereafter. The maximum doses estimated for the residential, industrial, and recreational scenarios, were 2.2,0.7, and 0.04 mrem in a year, respectively, and also declined after 2050. The radiological doses for all of the exposure scenarios outside the buffer zone were well below the performance . objectives.. Significant uncertainties exist in the f i r s t iteration Composite Analysis, with the largest uncertainty associated with the inventories of key mobile radionuclides. Other sources of...
Abstract. Theexperimental andtheoretical development of ion cyclotronradofrequency heating (ICRF)intoroidalmagnetically-confined plasmasrecentlyculminatedwith the demonstration of ICRFheatingof D-Tplasmas, firstin theTokamakFusionTestReactor(TFTR)and then in the Joint EuropeanTorus (JET). Variousheating schemesbased on the cyclotronresonances betweentheplasmaionsandtheappliedICRFwaveshavebeenused,includingsecondharmonic tritium, minoritydeuterium, minorityhelium-3,modeconversionat the D-T ion-ion hybrid layer,andandionBernstein waveheating. Secondharmonictritium heatingwasfirst shownto be effectivein a reactor-grade plasmain TFTR. D-minorityheatingon JET has led to the achievement of Q = 0.22,theratioof fusionpowerproducedto RFpowerinput,sustainedovera few energyconfinementtimes. In this paper, some of the key building blocks in the development ofrf heatingofplasmasarereviewedandprospectsfor the development of advanced methodsof plasmacontrolbasedontheapplication ofrf wavesarediscussed.
Schematic Diagram of Consequence Analysis iv 4.1 Illustration of Proposed Logic for Discretization of Variations Encountered in a Large, Natural, Multilayered, Groundwater Regime. 4-3 4.2 All Nodes Based on Variation in Aquifer Thickness of Elevation of Different Hydrogeologic Units and Stream Locations 4-5 4.3 Illustrative Example of Describing Interfaces of Two Materials in Well Log at a Node Location 4-8 4.4 Subdivision of the Given Region Into Two-Dimensional, Mixed-Order, Finite Elements Based on Nodalization of Figure 4.2 4-9 I 4.5 Three-Dimensional Finite Elements Generated from Two-Dimensional Surface Elements and Well Log Details at Each Node 4-11 5.1 Illustrative Sample Plot from PLOTEL 5-2 5.2 The Output from Program GRIDIN Provides a Means for Three-Dimensional Display of the Input Data of Results. 5-5 5.3
Geologic and geohydrologic data for the Paradox Basin have been used to simulate movement of ground water and radioactive contaminants from a hypothetical nuclear reactor spent fuel repository after an assumed accidental release. The pathlines, travel times and velocity of the ground water from the repository to the discharge locale (river) were determined after the disruptive event by use of a two-dimensional finite difference hydrologic model. The concentration of radioactive contaminants in the ground water was calculated along a series of flow tubes by use of a one-dimensional mass transport model which takes into account convection, dispersion, contaminant/ media interactions and radioactive decay. For the hypothetical site location and specific parameters used in this demonstration, it is found that Iodine-129 (1-129) is the only isotope reaching the Colorado River in significant concentration. The 1-129 is transported to the river at a maximum concentration of about 1.84 x 10-8 microcuries per milliliter (~Ci/ml). This concentration occurs about 8.0 x 10 5 years after the repository has been breached. This 1-129 groundwater concentration is about 0.3 of the drinking water standard for uncontrolled use. The groundwater concentration would then be diluted by the Colorado River (mean flow of 7,000 ft 3 /sec to about 2.13 x 10-13 ~Ci/ml. None of the actinide elements reach more than half the distance from the repository to the Colorado River in the two-million year model run time. As an example, Radium-226, at a maximum concentration, has travelled 0.46 of the distance to the river in two million years. Radium-226 concentration in the ground water at that point in space and time is 1.02 x 10-7 ~Ci/ml. This exercise demonstrates that the W1SAP model system is applicable for analysis of contaminant transport. The results presented in this report, however, are valid only for one particular set of parameters. A complete sensitivity analysis must be performed to evaluate the range of effects from the release of contaminants from a breached repository. iii. . SUMMARY LIST OF FIGURES.
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