Assessment of effectiveness of geologic isolation systems: a short description of the AEGIS approach

To meet licensing criteria and protection standards for HLW disposal, research programs are in progress to determine acceptable waste forms, canisters, backfill materials for the repository, and geological formations. Methods must be developed to evaluate the effectiveness of the total system. To meet this need, methods are being developed to assess the long-term effectiveness of isolating nuclear wastes in geologic formations. This work was started in 1976 in the Waste Isolation Safety Assessment Program (WISAP) and continues in the Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) Program. The evaluation of this long-term effectiveness involves a number of distinct steps. AEGIS currently has the methods for performing these evaluation steps. These methods are continuously being improved to meet the inreasing level of sophistication which will be required. AEGIS develops a conceptual description of the geologic systems and uses computer models to simulate the existing ground-water pathways. AEGIS also uses a team of consulting experts, with the assistance of a computer model of the geologic processes, to develop and evaluate plausible release scenarios. Then other AEGIS computer models are used to simulate the transport of radionuclides to the surface and the resultant radiation doses to individuals and populations. (DLC

Summary of FY-1978 consultant input for scenario methodology development

Associated with commercial nuclear power production in the United States is the generation of potentially hazardous radioactive waste products. The Department of Energy (DOE), through the National Waste Terminal Storage (NWTS) Program, is seeking to develop nuclear waste isolation systems in geologic formations. These underground waste isolation systems will preclude contact with the biosphere of waste radionuclides in concentrations which are sufficient to cause deleterious impact on humans or their environments. Comprehensive analyses of specific isolation systems are needed to assess the postclosure expectations of the systems. Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) program has been established for developing the capability of making those analyses. The assessment of repository post-closure safety has two basic components: identification and analyses of breach scenarios and the pattern of events and processes causing each breach, and identification and analyses of the environmental consequences of radionuclide transport and interactions subsequent to a repository breach. Specific processes and events which might affect potential repository sites and, the rates and probabilities for those phenomena are presented. The description of the system interactions and synergisms and of the repository system as an evolving and continuing process are included. Much of the preliminary information derived from the FY-1978 research effort is summarized in this document. This summary report contains information pertaining to the following areas of study: climatology, geomorphology, glaciology, hydrology, meteorites, sea level fluctuations, structural geology and volcanology

A temperature controller in the 6000 series

2.00SIGLELD:9091.9F(AERE-R--10298). / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Shell-side flow in a model disc-and-doughnut heat exchanger

SIGLELD:9091.9F(AERE-R--10831) / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Plate-fin heat exchangers Guide to their specification and use

97.00SIGLEAvailable from British Library Document Supply Centre- DSC:q89/10750(Plate-fin) / BLDSC - British Library Document Supply Centre1. edGBUnited Kingdo

Confronting climate change in the Gulf region: prospects for sustaining our ecological heritage

From Texas to Florida, the Gulf coast region is rich with ecological resources that support the region’s economic wealth. Over time, human activities from dam construction to shoreline development have dramatically altered natural landscapes, waterways, and ecological processes. Pressures from human activities remain the most important agents of ecological change in the region today. Over the century ahead, land-use changes are likely to increase as rapid population growth continues. Global climate change, driven by rising levels of carbon dioxide and other heat-trapping greenhouse gases in the atmosphere, will interact with, and magnify, other human stresses on Gulf Coast ecosystems and the goods and services they provide. Confronting Climate Change in the Gulf Coast Region explores the potential risks of climate change to Gulf Coast ecosystems in the context of pressures from land use. Its purpose is to help the public and policymakers understand the most likely ecological consequences of climate change in the region over the next 50 to 100 years and prepare to safeguard the economy, culture, and natural heritage of the Gulf Coast. This summary highlights key findings.Union of Concerned Scientists & Ecological Society of Americ

Weak-beam imaging of dissociated dislocations in HVEM-irradiated Fe-Ni-Cr alloys

We report here on studies by weak-beam electron microscopy of the evolution of microstructures at and near preexisting line dislocations in a number of Fe-Ni-Cr alloys under electronirradiation in a high-voltage electron microscope (HVEM). The detailed observations are discussed in terms of dislocation climb mechanisms in these materials and a model based on interstitial pipe diffusion

Borehole drilling and completion Details for the Harwell research site

SIGLELD:7570.285(ENPU--81-9). / BLDSC - British Library Document Supply CentreGBUnited Kingdo

The equilibrium leach testing of CAGR hulls

Also known as report no. DOE/RW--89.033Available from British Library Document Supply Centre- DSC:9091.9(AERE-R--12371) / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo