This paper presents the results of the application of CFD to ventilation calculations at Yucca Mountain using MULTIFLUX. Seven cases were selected to study the effect of the heat transport coefficient on the drift wall temperature distribution. It was concluded that variable heat transport coefficients such as those given by the differential-parameter CFD used in MULTIFLUX are considered the most appropriate approach of all cases presented. This CFD model agrees well with FLUENT results and produces the lowest temperature results, which is favorable to ventilation performance.

The Department of the Army is authorized to build and operate nuclear reactors for defense purposes under Paragraph 91b of the Atomic Energy Act of 1954 (1). As part of the Army Reactor Program, the United States Army Corps of Engineers (Corps) is responsible for nuclear reactor engineering and design, reactor construction, and decommissioning design and implementation (2). The Corps is currently focused on ensuring the safety and security of the Army's three deactivated power reactors and planning for their final decommissioning. To support decommissioning cost projections, the Corps is gathering information on the residual radiological and chemical hazards associated with each reactor, starting with the MH-1A reactor on the Sturgis Barge (3). Because the Sturgis Barge is moored in the James River Reserve Fleet, there were unique challenges that had to be overcome during the characterization survey and others that will become a concern when final decommissioning is to be per formed.

One type of HLW associated with the procedures of spent fuel reprocessing or conditioning as would be required in order to implement accelerator driven transmutation of waste, is the insoluble residue, which remains after the majority of the fuel, is dissolved. This material is separated as part of the head-end processing and must be suitably encapsulated within a waste-form to permit its disposal. In spite of the fact that the specific contribution of insoluble deposits, arising from SNF dissolution does not exceed 0,5-1 % of the general volume of wastes, the radionuclides, contained in them introduce a rather significant hazard and demand the most careful treatment of the material during its treatment and subsequent disposal. The main contributors to the insoluble residues are the slowly dissolving metallic fission product inclusions found in spent fuel and the certain fission products which although initially soluble precipitate during the dissolution process. The most significant elements, in mass terms are the platinum group metals (PGM) and, also molybdenum and zirconium. In turn, the formed deposits are capable of adsorbing fission products and actinides, for example, antimony, uranium and plutonium. This group of elements presents two issues one relating to the activity and heat of …

The Compact Sodium-cooled Nuclear Reactor Facility (KNK) was an experimental nuclear power plant of 20 MW electric power erected on the premises of the Karlsruhe Research Center. The plant was initially run as KNK I with a thermal core between 1971 and 1974 and then, between 1977 and 1991, with a fast core as the KNK II fast breeder plant. Under the decommissioning concept, the plant is to be decommissioned completely to green field conditions at the end of 2005 in ten steps, i.e. under the corresponding ten decommissioning permits. To this day, nine decommissioning permits have been issued, the first one in 1993 and the most recent one, number nine, in 2001. The decommissioning and demolition activities covered by decommissioning permits 1 to 7 have been completed. Under the 8th Decommissioning Permit, the components of the primary system and the rotating reactor top shield are to be removed by late 2001. Under the 9th Decommissioning Permit, the reactor vessel with its internals, the primary shield, and the biological shield are to be dismantled. The residual sodium volume in the reactor vessel was estimated to amount to approx. 30 l. The maximum Co-60 activation is on the order of 107-108 …

During the operation of Boiling Water Reactors, Control - Elements are used to control the neutron flux inside the reactor vessel. After the end of the lifetime, the Control - Elements are usually stored in the fuel - elements - pool of the reactor. Up to now, in Germany no conditioning of Control - Elements has been done in a BWR under operation.

In 1997, the UK programme for the deep disposal of radioactive waste was ''stopped dead in its tracks'' with the refusal by the Secretary of State for the Environment to allow Nirex to go ahead with its plans for an underground Rock Characterisation Facility at Sellafield in north-west England. Since that time a House of Lords' Select Committee has held an inquiry into what went wrong and what the way ahead should be. In addition, Nirex and the nuclear industry players have also been analyzing the past with a view to learning from the experience in taking things forward. In Nirex's view this is essentially an ethical issue; the waste exists and we should deal with it in this generation. Three areas need to be better addressed if a successful program of management of the nation's radioactive waste is to be achieved: the process of how policy development and implementation can be achieved; the structure of the nuclear industry and its relationship to the waste management organization; and the behavior of the players in their interaction with stakeholders. All three are underpinned by the need for transparency. In recognition that developing a policy for managing radioactive waste has to be …

Following a referendum in Italy in 1987, the four Nuclear Power Plants (NPPs) owned and operated by the state utility ENEL were closed. After closing the NPPs, ENEL selected a ''safestore'' decommissioning strategy; anticipating a safestore period of some 40-50 years. This approach was consistent with the funds collected during plant operation, and was reinforced by the lack of both a waste repository and a set of national free release limits for contaminated materials in Italy. During 1999, twin decisions were made to privatize ENEL and to transform the nuclear division into a separate subsidiary of the ENEL group. This group was renamed Sogin and during the following year, ownership of the company was transferred to the Italian Treasury. On formation, Sogin was asked by the Italian government to review the national decommissioning strategy. The objective of the review was to move from a safestore strategy to a prompt decommissioning strategy, with the target of releasing all of the nuclear sites by 2020. It was recognized that this target was conditional upon the availability of a national LLW repository together with interim stores for both spent fuel and HLW by 2009. The government also agreed that additional costs caused by …

The Department of Energy (DOE), Office of Environmental Management (EM) continues to pursue cost-effective, environmental cleanup of the weapons complex sites with a concomitant emphasis on deployment of innovative technologies as a means to this end. The EM Office of Science and Technology (OST) pursues a strategy that entails identification of technologies that have potential applications throughout the DOE complex: at multiple DOE sites and at multiple facilities on those sites. It further encourages a competitive procurement process for the various applications entailed in the remediation of a given facility. These strategies require a competitive private-sector supplier base to help meet EM needs. OST supports technology development and deployment through investments in partnerships with private industry to enhance the acceptance of their technology products within the DOE market. Since 1992, OST and the National Energy Technology Laboratory (NETL) have supported the re search and development of technology products and services offered by the private sector. During this time, NETL has managed over 140 research and development projects involving industrial and university partners. These projects involve research in a broad range of EM related topics, including deactivation and decommissioning, characterization, monitoring, sensors, waste separation, groundwater remediation, robotics, and mixed waste treatment. …

A study was performed to develop a strategy for the removal of fuel-containing material (FCM) from the Chernobyl Unit 4 Shelter and for the related waste management. This study was performed during Phase 1 of the Shelter Implementation Plan (SIP) and was funded by the Chernobyl Shelter Fund. The main objective for Phase 2 of the SIP is to stabilize the Shelter and to construct a New Confinement (NC) by the year 2007. In addition, the SIP includes studies on the strategy and on the conceptual design implications of the removal of FCM from the Shelter. This is considered essential for the ultimate goal, the transformation of the Shelter into an environmentally safe system.

Nickel alloys such as Alloy 600 undergo Stress Corrosion Cracking (SCC) in pure water at temperatures between about 260 C and the critical point. Increasing the level of Cr in Ni-Fe-Cr alloys increases SCC resistance in aerated and deaerated water. The mechanism is not understood. The effect of Cr composition on oxide microstructure and corrosion kinetics of Ni-Fe-Cr alloys was determined experimentally, to evaluate whether the anodic dissolution model for SCC can account for the effect of Cr on SCC. The alloy corrosion rate and corrosion product oxide microstructure is strongly influenced by the Cr composition. Corrosion kinetics are parabolic and influenced by chromium concentration, with the parabolic constant first increasing then decreasing as Cr increases from 5 to 39%. Surface analyses using Analytical Electron microscopy (AEM) and Auger Electron Spectroscopy (AES) show that the corrosion product film that forms initially on all alloys exposed to high purity high temperature water is a nickel rich oxide. With time, the amount of chromium in the oxide film increases and corrosion proceeds toward the formation of the more thermodynamically stable spinel or hexagonal Cr-rich oxides, similar to high temperature gaseous oxidation. Due to the slower diffusion kinetics at the temperatures of water …

During the last 20 years, utilities and researchers have begun to understand the value in the collection and analysis of interruption cost data. The continued investigation of the monetary impact of power outages will facilitate the advancement of the analytical methods used to measure the costs and benefits from the perspective of the energy consumer. More in-depth analysis may be warranted because of the privatization and deregulation of power utilities, price instability in certain regions of the U.S. and the continued evolution of alternative auxiliary power systems.

Reprocessing of fuel elements receives much consideration in nuclear engineering. Chemical and electrochemical methods are used for the purpose. For difficultly soluble materials based on zirconium alloys chemical methods are not suitable. Chemical reprocessing of defective or irradiated fuel elements requires special methods for their decladding because the dissolution of the clad material in nitric acid is either impossible (stainless steel, Zr alloys) or quite slow (aluminium). Fuel elements are cut in air-tight glove-boxes equipped with a dust collector and a feeder for crushed material. Chemical treatment is not free from limitations. For this reason we started a study of the feasibility of electrochemical methods for reprocessing defective and irradiated fuel elements. A simplified electrochemical technology developed makes it possible to recover expensive materials which were earlier wasted or required multi-step treatment. The method and an electrochemical cell are suitable for essentially complete dissolution of any fuel elements, specifically those made of materials which are difficultly soluble by chemical methods.

The Environmental Protection Agency (EPA) has issued radiation protection standards for the potential spent nuclear fuel and high-level radioactive waste disposal system in Yucca Mountain, Nevada. These standards are found in Part 197 of Title 40 of the Code of Federal Regulations (40 CFR Part 197). The Energy Policy Act of 1992 directed, and gave the authority to, EPA to take this action based upon input from the National Academy of Sciences (NAS). The final standards were published in the Federal Register (66 FR 32073) on 13 June 2001. The 40 CFR Part 197 standards have four major parts: (1) individual-protection during storage activities; (2) individual-protection following closure of the repository; (3) human-intrusion; and (4) ground-water protection. The storage standard is 150 microsieverts (Sv) annual committed effective dose equivalent (CEDE) to any member of the general public. The disposal standards are: (1) 150 Sv annual CEDE for the reasonably maximally exposed individual (RMEI) for 10,000 years after disposal; (2) 150 Sv received by the RMEI within 10,000 years after disposal as a result of human intrusion; and (3) the levels of radionuclides in the ground water cannot exceed 40 Sv from beta and gamma emitters, 5 picocuries per liter (pCi/L) …

Environmental remediation activities have been ongoing at the Weldon Spring Site for over a decade, beginning with small interim response actions and culminating in completion of surface cleanup as represented by closure of the 17 hectare (42-acre) on-site disposal cell. As remedial actions have incrementally been accomplished, the occurrence of site-related contaminants in on and off-site environmental media have effectively been reduced. The DOE-WSSRAP has demonstrated success through the effective reduction or elimination of site related water and airborne contaminants along multiple migration pathways. This paper briefly describes the remedial measures affected at Weldon Spring, and quantifies the environmental responses to those remedial measures.

This user's guide documents the capabilities and functions of the Expanded Time Phase Force Deployment Data (TPFDD) Editor (ETEdit) software application. Step-by-step procedures for using ETEdit are provided in Chapter 5. Although ETEdit is primarily an editing tool for use with various software applications, it can also be used as a stand-alone application or in tandem with another application. It provides force module data that allow you to display and modify movement requirements, as well as to display the requirement line numbers (RLNs) for both detail and parent hierarchy. The primary purpose of ETEdit is to make changes to TPFDDs. Because it has been designed as a separate application, you can apply the ETEdit capabilities for use with other models.

The necessity to develop the submarine fleet in Russia required constructing a special training base for the training of submarine crews. To this purpose two prototypes of nuclear power units, close analogous to those fitting out nuclear submarines were constructed and commissioned in the sixties on the Navy training centre's base located in Paldiski (Pakri peninsula, Estonia). In 1994, nuclear fuel was discharged from the reactors and transported to Russia while the reactors themselves were prepared for prolonged storage, prior to transfer of the Paldiski facilities to the ownership of the Estonian Republic. The Paldiski facilities are currently being dismantled with the exception of two sarcophagi made of concrete that are housing the two reactor compartments. The question of the future management of both sarcophagi is a key-issue in the cleaning up of the whole Paldiski site. Actually, three basic questions should answered: when should dismantling operations occur, how this should be done, and what could be the corresponding cost. Within the context of enlargement of the European Union, the Commission services (first Directorate-General for Environment and then Directorate-General for Enlargement) decided to support Estonia to respond to these three questions through a study contract that was awarded in 1999 …

Since 1998, the Department of Energy's (DOE) Office of Environmental Management has funded the Accelerated Site Technology Deployment (ASTD) Program to expedite deployment of alternative technologies that can save time and money for the environmental cleanup at DOE sites across the nation. The ASTD program has accelerated more than one hundred deployments of new technologies under 76 projects that focus on a broad spectrum of EM problems. More than 25 environmental restoration projects have been initiated to solve the following types of problems: characterization of the subsurface using chemical, radiological, geophysical, and statistical methods; treatment of groundwater contaminated with DNAPLs, metals, or radionuclides; and other projects such as landfill covers, purge water management systems, and treatment of explosives-contaminated soils. One of the major goals of the ASTD Program is to deploy a new technology or process at multiple DOE sites. ASTD projects are encouraged to identify subsequent deployments at other sites. Some of the projects that have successfully deployed technologies at multiple sites focusing on cleanup of contaminated groundwater include: Permeable Reactive Barriers (Monticello, Rocky Flats, and Kansas City), treating uranium and organics in groundwater; and Dynamic Underground Stripping (Portsmouth, and Savannah River), thermally treating DNAPL source zones. Each year …

The Nuclear Materials Stewardship Initiative was established in January, 2000, to accelerate the work of achieving integration and cutting long-term costs associated with the management of nuclear materials. As part of that initiative, the Department of Energy (DOE), Office of Environmental Management (EM), has established Nuclear Material Management Groups for the management of excess nuclear materials. As one of these groups, the Plutonium Material Management Group (PMMG) has been chartered to serve as DOE's complex wide resource and point of contact for technical coordination and program planning support in the safe and efficient disposition of the nations excess Plutonium 239. This paper will explain the mission, goals, and objectives of the PMMG. In addition, the paper will provide a broad overview of the status of the plutonium inventories throughout the DOE complex. The DOE currently manages approximately 99.5 MT of plutonium isotopes. Details of the various categories of plutonium, from material designated for national security needs through material that has been declared excess, will be explained. For the plutonium that has been declared excess, the various pathways to disposition (including reuse, recycling, sale, transfer, treatment, consumption, and disposal) will be discussed. At this time 52.5 MT of plutonium has been …

This paper summarizes the extensive structural analysis and design of the support saddles for the Extended Barrel of the ATLAS Tilecalorimeter that has taken place at Argonne National Laboratory over the past several months. This work has been a continuation and expansion of work that has taken place over the course of several years within the ATLAS Tilecalorimeter collaboration. This paper will be divided into four main sections. Section 1 is the introduction to the analysis and will give a brief history of the work that had previously been done. Section 2 examines the design and structural analysis that has occurred on the support saddles. The design of the support saddles has evolved over the last few months. There are three main analyses of the saddles that are discussed in Section 2. First, the forces that act upon the support saddles and the resulting deflections and stresses are examined when the support saddle is subjected only to gravity loading. Next, the saddles are examined when subjected to a combination of gravity and a seismic load of .15g in the X, Y, and Z directions. Finally, the saddles are analyzed when subjected to a combination of gravity, magnetic, and seismic loading. …

This paper presents an overview of the underground technologies deployed during the cleanup of nine large underground storage tanks (USTs) that contained residual radioactive sludge, liquid low-level waste (LLLW), and other debris. The Gunite Tanks Remediation Project at Oak Ridge National Laboratory (ORNL) was successfully completed in 2001, ending with the stabilization of the USTs and the cleanup of the South Tank Farm. This U.S. Department of Energy (DOE) project was the first of its kind completed in the United States of America. The Project integrated robotic and remotely operated technologies into an effective tank waste retrieval system that safely retrieved more than 348 m3 (92,000 gal) of radioactive sludge and 3.15E+15 Bq (85,000 Ci) of radioactive contamination from the tanks. The Project successfully transferred over 2,385 m3 (630,000 gal) of waste slurry to ORNL's active tank waste management system. The project team avoided over $120 Million in costs and shortened the original baseline schedule by over 10 years. Completing the Gunite Tanks Remediation Project eliminated the risks posed by the aging USTs and the waste they contained, and avoid the $400,000 annual costs associated with maintaining and monitoring the tanks.

The Department of Energy, Idaho Operations Office (DOE-ID) is making preparations to close two underground high-level waste (HLW) storage tanks at the Idaho National Engineering and Environmental Laboratory (INEEL) to meet Resource Conservation and Recovery Act (RCRA) regulations and Department of Energy orders. Closure of these two tanks is scheduled for 2004 as the first phase in closure of the eleven 300,000 gallon tanks currently in service at the Idaho Nuclear Technology and Engineering Center (INTEC). The INTEC Tank Farm Facility (TFF) Closure sequence consists of multiple steps to be accomplished through the existing tank riser access points. Currently, the tank risers contain steam and process waste lines associated with the steam jets, corrosion coupons, and liquid level indicators. As necessary, this equipment will be removed from the risers to allow adequate space for closure equipment and activities.

The Subsurface Contaminants Focus Area, (SCFA) is committed to, and has been accountable for, identifying and providing solutions for the most pressing subsurface contamination problems in the DOE Complex. The SCFA program is a DOE end user focused and problem driven organization that provides the best technical solutions for the highest priority problems. This paper will discuss in some detail specific examples of the most successful, innovative technical solutions and the DOE sites where they were deployed or demonstrated. These solutions exhibited outstanding performance in FY 2000/2001 and appear poised to achieve significant success in saving end users money and time. They also provide a reduction in risk to the environment, workers, and the public while expediting environmental clean up of the sites.

At the Idaho National Engineering and Environmental Laboratory (INEEL), a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) treatability study is being performed to examine the technology of in situ grouting for final in situ disposal of buried mixed transuranic (TRU) waste. At the INEEL, there is over 56,000 cubic meters of waste commingled with a similar amount of soil in a shallow (3-5 m) land burial referred to as Waste Area Group 7-13/14. Since this buried waste has been declared on the National Priorities List under CERCLA, it is being managed as a superfund site. Under CERCLA, options for this waste include capping and continued monitoring, retrieval and ex situ management of the retrieved waste, in situ stabilization by vitrification or grouting, in situ thermal dissorption, or some combination of these options. In situ grouting involves injecting grout at high pressures (400 bars) directly into the waste to create a solid monolith. The in situ grouting process is expected to both stabilize the waste against subsidence and provide containment against migration of waste to the Snake River Plain Aquifer lying 150-200 m below the waste. The treatability study involves bench testing, implementability testing, and field testing. The bench testing …

The U.S. Department of Energy (USDOE) created the Formerly Utilized Sites Remedial Action Program (FUSRAP) in 1974 to identify, investigate, and cleanup or control radiological contamination at sites used by the Manhattan Engineer District (MED) and the Atomic Energy Commission (AEC) from the 1940s through the 1960s. The USDOE had identified 46 sites in the program and finished remediation at 24 of the smaller ones before the end of 1997. With the passage of the Energy and Water Resources Appropriation Act of 1998 the United States Army Corps of Engineers (USACE) was designated by Congress with responsibility to manage and execute the FUSRAP. The Linde Site located in Tonawanda, New York was operated by the MED from 1942-1946 to extract uranium from several high-grade ores. This natural uranium was subsequently enriched in U-235 elsewhere in the United States and ultimately used to produce energy or weapons. Though in the process of reviewing alternative disposal options by 1995, the USDOE had operated FUSRAP with a strategy requiring virtually all materials remediated be disposed of at only one Nuclear Regulatory Commission licensed facility. The change in management of the FUSRAP in 1997 allowed the disposal policy of low levels of radioactively contaminated …