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Description: Tritium contaminated concrete rubble from the 232-F Tritium Facility was disposed in the Slit 1 Trenches 1 and 2 in 1997. A Special Analysis (SA) has been performed to evaluate any impact this disposal may have on the groundwater. The SA assumed that the disposed concrete rubble was fully saturated at the time of disposal, however if the concrete was less than fully saturated, migration of tritium out of the concrete would be slower than under fully saturated conditions. Therefore if the concrete at disposal was less than fully saturated, the PA assumption of full saturation would be a conservative assumption. In order to evaluate whether the PA assumption resulted in a conservative analysis from the standpoint of the concrete saturation, concrete rubble samples were collected from various facilities being demolished at the Savannah River Site (SRS) and evaluated for in-field moisture content, absorbable moisture, and water exchangeable porosity. The purpose of this task was to collect concrete rubble samples from various demolished SRS facilities for the purpose of determining in-field moisture content, absorbable moisture, and water exchangeable porosity. Since moisture content testing for concrete rubble is not typical, existing ASTM Standards were reviewed for method and procedure development.
Date: October 7, 2005
Creator: Phifer, M
Partner: UNT Libraries Government Documents Department

Numerical modeling of self-limiting and self-enhancing caprock alteration induced by CO2 storage in a depleted gas reservoir

Description: This paper presents numerical simulations of reactive transport which may be induced in the caprock of an on-shore depleted gas reservoir by the geological sequestration of carbon dioxide. The objective is to verify that CO{sub 2} geological disposal activities currently being planned for the study area are safe and do not induce any undesired environmental impact. In our model, fluid flow and mineral alteration are induced in the caprock by penetration of high CO{sub 2} concentrations from the underlying reservoir, where it was assumed that large amounts of CO{sub 2} have already been injected at depth. The main focus is on the potential effect of precipitation and dissolution processes on the sealing efficiency of caprock formations. Concerns that some leakage may occur in the investigated system arise because the seal is made up of potentially highly-reactive rocks, consisting of carbonate-rich shales (calcite+dolomite averaging up to more than 30% of solid volume fraction). Batch simulations and multi-dimensional 1D and 2D modeling have been used to investigate multicomponent geochemical processes. Numerical simulations account for fracture-matrix interactions, gas phase participation in multiphase fluid flow and geochemical reactions, and kinetics of fluid-rock interactions. The geochemical processes and parameters to which the occurrence of high CO{sub 2} concentrations are most sensitive are investigated by conceptualizing different mass transport mechanisms (i.e. diffusion and mixed advection+diffusion). The most relevant mineralogical transformations occurring in the caprock are described, and the feedback of these geochemical processes on physical properties such as porosity is examined to evaluate how the sealing capacity of the caprock could evolve in time. The simulations demonstrate that the occurrence of some gas leakage from the reservoir may have a strong influence on the geochemical evolution of the caprock. In fact, when a free CO{sub 2}-dominated phase migrates into the caprock through fractures, or through zones ...
Date: September 7, 2007
Creator: Xu, Tianfu; Gherardi, Fabrizio; Xu, Tianfu & Pruess, Karsten
Partner: UNT Libraries Government Documents Department

Emergency response monitoring activities and environmental impact of the K-Reactor aqueous tritium release of December 1991

Description: Approximately 150 gallons of tritiated water leaked from one of the K-Reactor heat exchangers between December 22 and December 25, 1991. Upon notification, the Environmental Technology Section (ETS) activated its emergency response team to provide predictions of river concentrations, transport times, and radiological effects to downstream water users. Additionally, within a few days of the release, ETS and the Environmental Monitoring Section (EMS) began a comprehensive program to collect and analyze surface water samples from SRS down to the Savannah River estuary. The TRAC mobile laboratory was deployed to the Beaufort-Jasper water treatment plant to provide initial analyses for downriver water samples. This document discusses the results of the sampling activities. Concentration levels are provided along with hypothetical maximum individual doses.
Date: February 7, 1992
Creator: Hamby, D.M.; Addis, R.P.; Beals, D.M.; Cadieux, J.R.; Carlton, W.H.; Dunn, D.L. et al.
Partner: UNT Libraries Government Documents Department

Meteorological data for SRI study of mesoscale weather effects by pilot plant

Description: The data required to estimate the probability of occurrence of initial meteorological conditions leading to an effect on the weather by the pilot solar thermal electric plant are discussed. No completely appropriate data summaries are available. Vertical atmospheric profiles are the most appropriate source of raw data for a statistical analysis, but these are not available from the pilot plant location either. The available stability data for the pilot plant site are presented. A procedure is outlined to obtain the required estimates of occurrence frequency if desired. However, it is recommended that more substantial effects be demonstrated with a physically realistic model before great effort is expended on data analysis.
Date: May 7, 1980
Partner: UNT Libraries Government Documents Department

Integrated assessment and the relation between land-use change and climate change

Description: Integrated assessment is an approach that is useful in evaluating the consequences of global climate change. Understanding the consequences requires knowledge of the relationship between land-use change and climate change. Methodologies for assessing the contribution of land-use change to atmospheric CO{sub 2} concentrations are considered with reference to a particular case study area: south and southeast Asia. The use of models to evaluate the consequences of climate change on forests must also consider an assessment approach. Each of these points is discussed in the following four sections.
Date: October 7, 1994
Creator: Dale, V.H.
Partner: UNT Libraries Government Documents Department

New National Conservation Training Center a model of energy-efficient design: FEMP technical assistance case study fact sheet

Description: This FEMP technical assistance case study shows that energy efficiency, cost effectiveness, and aesthetics can be incorporated into the design of a Federal facility--in this case the National Conservation Training Center in Shepherdstown, WV, which encompasses many buildings with a variety of purposes.
Date: October 7, 1998
Creator: Atkison, K.
Partner: UNT Libraries Government Documents Department

Depleted uranium hexafluoride management program : data compilation for the Paducah site.

Description: This report is a compilation of data and analyses for the Paducah site, near Paducah, Kentucky. The data were collected and the analyses were done in support of the U.S. Department of Energy (DOE) 1999 Programmatic Environmental Impact Statement for Alternative Strategies for the Long-Term Management and Use of Depleted Uranium Hexafluoride (DOE/EIS-0269). The report describes the affected environment at the Paducah site and summarizes potential environmental impacts that could result from conducting the following depleted uranium hexafluoride (UF{sub 6}) activities at the site: continued cylinder storage, preparation of cylinders for shipment, conversion, and long-term storage. DOE's preferred alternative is to begin converting the depleted UF{sub 6} inventory as soon as possible to either uranium oxide, uranium metal, or a combination of both, while allowing for use of as much of this inventory as possible.
Date: June 7, 2001
Creator: Hartmann, H.
Partner: UNT Libraries Government Documents Department

Comparative analysis of selected fuel cell vehicles

Description: Vehicles powered by fuel cells operate more efficiently, more quietly, and more cleanly than internal combustion engines (ICEs). Furthermore, methanol-fueled fuel cell vehicles (FCVs) can utilize major elements of the existing fueling infrastructure of present-day liquid-fueled ICE vehicles (ICEVs). DOE has maintained an active program to stimulate the development and demonstration o fuel cell technologies in conjunction with rechargeable batteries in road vehicles. The purpose of this study is to identify and assess the availability of data on FCVs, and to develop a vehicle subsystem structure that can be used to compare both FCVs and ICEV, from a number of perspectives--environmental impacts, energy utilization, materials usage, and life cycle costs. This report focuses on methanol-fueled FCVs fueled by gasoline, methanol, and diesel fuel that are likely to be demonstratable by the year 2000. The comparative analysis presented covers four vehicles--two passenger vehicles and two urban transit buses. The passenger vehicles include an ICEV using either gasoline or methanol and an FCV using methanol. The FCV uses a Proton Exchange Membrane (PEM) fuel cell, an on-board methanol reformer, mid-term batteries, and an AC motor. The transit bus ICEV was evaluated for both diesel and methanol fuels. The transit bus FCV runs on methanol and uses a Phosphoric Acid Fuel Cell (PAFC) fuel cell, near-term batteries, a DC motor, and an on-board methanol reformer. 75 refs.
Date: May 7, 1993
Partner: UNT Libraries Government Documents Department

Meeting Summary, Credit Trading Work Group

Description: OAK-B135 Credit Trading Work Group Meeting Summary. The purpose of the meeting is to: (1) Provide an opportunity for NWCC Work Group Members, NWCC Members, and invited expert participants to hear an overview of the draft NWCC Credit Trading Report and to critically review and discuss the report's recommendations and principles. (2) Hear presentations from several perspectives of other experts on credit trading which provide: (a) a brief summary of credit trading activities they are involved in, and (b) critical responses to the NWCC draft report. (3) Identify how the report can be improved at the big picture level. Attempt to resolve issues or concerns if necessary. (4) Discuss the recommendations and credit trading principles in detail and attempt to reach consensus on these sections for presentation to the NWCC. (5) Discuss if any of the outreach and communication recommendations in the report should be conducted by the NWCC.
Date: December 7, 2000
Creator: Bryan, Kevin
Partner: UNT Libraries Government Documents Department

NUTRAN: a computer model of long-term hazards from waste repositories

Description: The NUTRAN package of computer programs calculates doses to humans from radioactivity carried out of deep geologic waste repositories by groundwater. It consists of four codes: ORIGEN (developed by Oak Ridge National Laboratory), which treats the formation and decay of radionuclides, WASTE, which computes the transport of radionuclides in ground water, BIODOSE, which calculates radionuclide transport in surface waters and ecosystems and human exposures, and WPPLOT, which combines the results of WASTE and BIODOSE into usefully formatted outputs. This report describes what the WASTE, BIODOSE, and WPPLOT codes do. The equations they compute are presented in detail and their meaning is explained. Auxiliary programs which facilitate input and data management operations are also described.
Date: December 7, 1979
Creator: Ross, B.; Koplik, C.M.; Giuffre, M.S.; Hodgin, S.P. & Duffy, J.J.
Partner: UNT Libraries Government Documents Department

Pre-sealing risk analysis

Description: This report describes studies of accidents involving high-level radioactive waste before sealing the waste into a repository. The report summarizes work done in this area during Fiscal Year 1978 and supplements previous work. Models of accident probability, severity, and consequences are refined and extended.
Date: January 7, 1980
Creator: Ensminger, D.A.; Hough, M.E. & Oston, S.G.
Partner: UNT Libraries Government Documents Department