Decommissioning strategy and schedule for a multiple reactor nuclear power plant site

Energy Technology Data Exchange (ETDEWEB)

Monteiro, Deiglys Borges; Moreira, Joao M.L.; Maiorino, Jose Rubens, E-mail: deiglys.monteiro@ufabc.edu.br, E-mail: joao.moreira@ufabc.edu.br, E-mail: joserubens.maiorino@ufabc.edu.br [Universidade Federal do ABC (CECS/UFABC), Santo Andre, SP (Brazil). Centro de Engenharia, Modelagem e Ciencias Aplicadas

2015-07-01

The decommissioning is an important part of every Nuclear Power Plant life cycle gaining importance when there are more than one plant at the same site due to interactions that can arise from the operational ones and a decommissioning plant. In order to prevent undesirable problems, a suitable strategy and a very rigorous schedule should implemented and carried. In this way, decommissioning tasks such as fully decontamination and dismantling of activated and contaminated systems, rooms and structures could be delayed, posing as an interesting option to multiple reactor sites. The present work aims to purpose a strategy and a schedule for the decommissioning of a multiple reactor site highlighting the benefits of delay operational tasks and constructs some auxiliary services in the site during the stand by period of the shutdown plants. As a case study, will be presented a three-reactor site which the decommissioning process actually is in planning stage and that should start in the next decade. (author)

Decommissioning strategy and schedule for a multiple reactor nuclear power plant site

International Nuclear Information System (INIS)

Monteiro, Deiglys Borges; Moreira, Joao M.L.; Maiorino, Jose Rubens

2015-01-01

The decommissioning is an important part of every Nuclear Power Plant life cycle gaining importance when there are more than one plant at the same site due to interactions that can arise from the operational ones and a decommissioning plant. In order to prevent undesirable problems, a suitable strategy and a very rigorous schedule should implemented and carried. In this way, decommissioning tasks such as fully decontamination and dismantling of activated and contaminated systems, rooms and structures could be delayed, posing as an interesting option to multiple reactor sites. The present work aims to purpose a strategy and a schedule for the decommissioning of a multiple reactor site highlighting the benefits of delay operational tasks and constructs some auxiliary services in the site during the stand by period of the shutdown plants. As a case study, will be presented a three-reactor site which the decommissioning process actually is in planning stage and that should start in the next decade. (author)

Set of rules SOR 2 reactor site criteria

International Nuclear Information System (INIS)

1976-06-01

The purpose of this set of rules is to describe criteria which guide the Director in his evaluation of the suitability of proposed sites for stationary power and testing reactors subject to SOR 2. (B.G.)

Site Suitability and Hazard Assessment Guide for Small Modular Reactors

Energy Technology Data Exchange (ETDEWEB)

Wayne Moe

2013-10-01

Commercial nuclear reactor projects in the U.S. have traditionally employed large light water reactors (LWR) to generate regional supplies of electricity. Although large LWRs have consistently dominated commercial nuclear markets both domestically and abroad, the concept of small modular reactors (SMRs) capable of producing between 30 MW(t) and 900 MW(t) to generating steam for electricity is not new. Nor is the idea of locating small nuclear reactors in close proximity to and in physical connection with industrial processes to provide a long-term source of thermal energy. Growing problems associated continued use of fossil fuels and enhancements in efficiency and safety because of recent advancements in reactor technology suggest that the likelihood of near-term SMR technology(s) deployment at multiple locations within the United States is growing. Many different types of SMR technology are viable for siting in the domestic commercial energy market. However, the potential application of a particular proprietary SMR design will vary according to the target heat end-use application and the site upon which it is proposed to be located. Reactor heat applications most commonly referenced in connection with the SMR market include electric power production, district heating, desalinization, and the supply of thermal energy to various processes that require high temperature over long time periods, or a combination thereof. Indeed, the modular construction, reliability and long operational life purported to be associated with some SMR concepts now being discussed may offer flexibility and benefits no other technology can offer. Effective siting is one of the many early challenges that face a proposed SMR installation project. Site-specific factors dealing with support to facility construction and operation, risks to the plant and the surrounding area, and the consequences subsequent to those risks must be fully identified, analyzed, and possibly mitigated before a license

Status of University of Cincinnati reactor-site nuclear engineering graduate programs

International Nuclear Information System (INIS)

Anno, J.N.; Christenson, J.M.; Eckart, L.E.

1993-01-01

The University of Cincinnati (UC) nuclear engineering program faculty has now had 12 yr of experience in delivering reactor-site educational programs to nuclear power plant technical personnel. Currently, with the sponsorship of the Toledo-Edison Company (TED), we are conducting a multiyear on-site graduate program with more than 30 participants at the Davis-Besse nuclear power plant. The program enables TED employees with the proper academic background to earn a master of science (MS) degree in nuclear engineering (mechanical engineering option). This paper presents a brief history of tile evolution of UC reactor-site educational programs together with a description of the progress of the current program

Brazilian nuclear power plants decommissioning plan for a multiple reactor site

Energy Technology Data Exchange (ETDEWEB)

Monteiro, Deiglys B.; Moreira, Joao M.L.; Maiorino, Jose R., E-mail: deiglys.monteiro@ufabc.edu.br, E-mail: joao.moreira@ufabc.edu.br, E-mail: joserubens.maiorino@ufabc.edu.br [Universidade Federal do ABC (CECS/UFABC), Santo Andre, SP (Brazil). Centro de Engenharia, Modelagem e Ciencias Aplicadas. Programa de Pos-Graduacao em Energia e Engenharia da Energia

2015-07-01

Actually, Brazil has two operating Nuclear Power Plants and a third one under construction, all at Central Nuclear Almirante Alvaro Alberto - CNAAA. To comply with regulatory aspects the power plants operator, Eletronuclear, must present to Brazilian Nuclear Regulatory Agency, CNEN, a decommissioning plan. Brazilian experience with decommissioning is limited because none of any nuclear reactor at the country was decommissioned. In literature, decommissioning process is well described despite few nuclear power reactors have been decommissioned around the world. Some different approach is desirable for multiple reactors sites, case of CNAAA site. During the decommissioning, a great amount of wastes will be produced and have to be properly managed. Particularly, the construction of Auxiliary Services on the site could be a good choice due to the possibility of reducing costs. The present work intends to present to the Eletronuclear some aspects of the decommissioning concept and decommissioning management, storage and disposal de wastes, based on the available literature, regulatory standards of CNEN and international experience as well as to suggest some solutions to be implemented at CNAAA site before starts the decommissioning project in order to maximize the benefits. (author)

Brazilian nuclear power plants decommissioning plan for a multiple reactor site

International Nuclear Information System (INIS)

Monteiro, Deiglys B.; Moreira, Joao M.L.; Maiorino, Jose R.

2015-01-01

Actually, Brazil has two operating Nuclear Power Plants and a third one under construction, all at Central Nuclear Almirante Alvaro Alberto - CNAAA. To comply with regulatory aspects the power plants operator, Eletronuclear, must present to Brazilian Nuclear Regulatory Agency, CNEN, a decommissioning plan. Brazilian experience with decommissioning is limited because none of any nuclear reactor at the country was decommissioned. In literature, decommissioning process is well described despite few nuclear power reactors have been decommissioned around the world. Some different approach is desirable for multiple reactors sites, case of CNAAA site. During the decommissioning, a great amount of wastes will be produced and have to be properly managed. Particularly, the construction of Auxiliary Services on the site could be a good choice due to the possibility of reducing costs. The present work intends to present to the Eletronuclear some aspects of the decommissioning concept and decommissioning management, storage and disposal de wastes, based on the available literature, regulatory standards of CNEN and international experience as well as to suggest some solutions to be implemented at CNAAA site before starts the decommissioning project in order to maximize the benefits. (author)

Changing concepts of geologic structure and the problem of siting nuclear reactors: examples from Washington State

International Nuclear Information System (INIS)

Tabor, R.W.

1986-01-01

The conflict between regulation and healthy evolution of geological science has contributed to the difficulties of siting nuclear reactors. On the Columbia Plateau in Washington, but for conservative design of the Hanford reactor facility, the recognition of the little-understood Olympic-Wallowa lineament as a major, possibly still active structural alignment might have jeopardized the acceptability of the site for nuclear reactors. On the Olympic Peninsula, evolving concepts of compressive structures and their possible recent activity and the current recognition of a subducting Juan de Fuca plate and its potential for generating great earthquakes - both concepts little-considered during initial site selection - may delay final acceptance of the Satsop site. Conflicts of this sort are inevitable but can be accommodated if they are anticipated in the reactor-licensing process. More important, society should be increasing its store of geologic knowledge now, during the current recess in nuclear reactor siting

Demographic statistics pertaining to nuclear power reactor sites

International Nuclear Information System (INIS)

1979-10-01

Population statistics are presented for 145 nuclear power plant sites. Summary tables and figures are included that were developed to aid in the evaluation of trends and general patterns associated with the various parameters of interest, such as the proximity of nuclear plant sites to centers of population. The primary reason for publishing this information at this time is to provide a factual basis for use in discussions on the subject of reactor siting policy. The report is a revised and updated version of a draft report published in December 1977. Errors in the population data base have been corrected and new data tabulations added

Engineering simulator applications to emergency preparedness at DOE reactor sites

International Nuclear Information System (INIS)

Beelman, R.J.

1990-01-01

This paper reports that since 1984 the Idaho National Engineering Laboratory (INEL) has conducted twenty-seven comprehensive emergency preparedness exercises at the U.S. Nuclear Regulatory Commission's (NRC) Headquarters Operations Center and Regional Incident Response Centers using the NRC's Nuclear Plant Analyzer (NPA), developed at the INEL, as an engineering simulator. The objective of these exercises has been to assist the NRC in upgrading its preparedness to provide technical support backup and oversight to U.S. commercial nuclear plant licensees during emergencies. With the current focus on Department of Energy (DOE) reactor operational safety and emergency preparedness, this capability is envisioned as a means of upgrading emergency preparedness at DOE production and test reactor sites such as the K-Reactor at Savannah River Laboratory (SRL) and the Advanced Test Reactor (ATR) at INEL

Savannah River Site reactor hardware design modification study

International Nuclear Information System (INIS)

Fisher, J.E.

1990-01-01

A study was undertaken to assess the merits of proposed design modifications to the Savannah River Site (SRS) reactors. The evaluation was based on the responses calculated by the RELAP5 systems code to double-ended guillotine break loss-of-coolant-accidents (DEGB LOCAs). The three concepts evaluated were (a) elevated plenum inlet piping with a guard vessel and clamshell enclosures, (b) closure of both rotovalves in the affected loop, and (c) closure of the pump suction valve in the affected loop. Each concept included a fast reactor shutdown (to 65% power in 100 ms) and a 2-s ac pump trip. System recovery potential was evaluated for break locations at the pump suction, the pump discharge, and the plenum inlet. The code version used was RELAP5/MOD2.5 version 3d3, a preliminary version of RELAP5/MOD3. The model was a three-dimensional representation of the K-Reactor water plenum and moderator tank. It included explicit representations of all six loops, which were based on the configuration of L-Reactor. A combination of features is recommended to ensure liquid inventory recovery for all break locations. Valve closure design performance for a break location in the short section of piping between the reactor concrete shield and the pump suction valve would benefit from the clamshell enclosing that section of piping. 7 refs., 10 figs., 2 tabs

Siting study for small platform-mounted industrial energy reactors

International Nuclear Information System (INIS)

1975-07-01

Utilizing an existing 313 MW(t) ship propulsion reactor design, a concept has been formulated for a floating platform-mounted nuclear plant and an evaluation has been made to determine reductions in construction time and cost achievable by repetitive platform construction in a shipyard. Concepts and estimates are presented for siting platform-mounted nuclear plants at the location of industrial facilities where the nuclear plants would furnish industrial process heat and/or electrical power. The representative industrial site designated for this study is considered typical of sites that might be used along the extensive network of navigable canals adjacent to the ocean and is similar to potential sites along the inland waterways of the United States

Discussion about design basis flood of site of research reactors by river

International Nuclear Information System (INIS)

Rong Feng; Zhao Jianjun; Du Qiaomin; Zhang Lingyan

2006-01-01

This paper presents the well-defined standard in relation to design the basis flood of the sites of research reactors by river. It is based on the concept of some relational standards, analysis of hydrological calculation technology and methods, and analysis of accident dangerous degrees of research reactor, as well as in combination with the engineering practices. The flood preventing standard for research reactors with higher power should be the same with that of the nuclear power plants. (authors)

The Oklo reactors: five years of exploration of the site

International Nuclear Information System (INIS)

Naudet, R.

1978-01-01

The main phases of the exploration of the Oklo site since the discovery of the ''reactor'' phenomenon are outlined briefly. Over 180 sampling holes were drilled during the interruption of the mining activities in the sector concerned. Several new zones have been found. Mining was resumed in the second half of 1975, providing an opportunity for highly fruitful geological follow-up work: more precise knowledge was gained of the morphology of the reactors, and very many additional samples were taken. Plant treatment of the ore and the systematic analysis of batches have made it possible to establish a balance of missing uranium-235. A small portion containing sites of intense reaction has been preserved by being anchored to the quarry wall. Mining in this sector has now finished, but new indications of fission have been found, especially in the Okelobondo sector. (author)

COPS model estimates of LLEA availability near selected reactor sites

International Nuclear Information System (INIS)

Berkbigler, K.P.

1979-11-01

The COPS computer model has been used to estimate local law enforcement agency (LLEA) officer availability in the neighborhood of selected nuclear reactor sites. The results of these analyses are presented both in graphic and tabular form in this report

Draft environmental impact statement siting, construction, and operation of New Production Reactor capacity. Volume 4, Appendices D-R

Energy Technology Data Exchange (ETDEWEB)

None

1991-04-01

This Environmental Impact Statement (EIS) assesses the potential environmental impacts, both on a broad programmatic level and on a project-specific level, concerning a proposed action to provide new tritium production capacity to meet the nation`s nuclear defense requirements well into the 21st century. A capacity equivalent to that of about a 3,000-megawatt (thermal) heavy-water reactor was assumed as a reference basis for analysis in this EIS; this is the approximate capacity of the existing production reactors at DOE`s Savannah River Site near Aiken, South Carolina. The EIS programmatic alternatives address Departmental decisions to be made on whether to build new production facilities, whether to build one or more complexes, what size production capacity to provide, and when to provide this capacity. Project-specific impacts for siting, constructing, and operating new production reactor capacity are assessed for three alternative sites: the Hanford Site near Richland, Washington; the Idaho National Engineering Laboratory near Idaho Falls, Idaho; and the Savannah River Site. For each site, the impacts of three reactor technologies (and supporting facilities) are assessed: a heavy-water reactor, a light-water reactor, and a modular high-temperature gas-cooled reactor. Impacts of the no-action alternative also are assessed. The EIS evaluates impacts related to air quality; noise levels; surface water, groundwater, and wetlands; land use; recreation; visual environment; biotic resources; historical, archaeological, and cultural resources; socioeconomics; transportation; waste management; and human health and safety. The EIS describes in detail the potential radioactive releases from new production reactors and support facilities and assesses the potential doses to workers and the general public. This volume contains 15 appendices.

The Hanford Site N Reactor buildings task identification and evaluation of historic properties

International Nuclear Information System (INIS)

Stapp, D.C.; Marceau, T.E.

1996-01-01

The New Production Reactor complex at Hanford (hereafter referred to as N Reactor) is proposed to be deactivated, decommissioned, and demolished in the coming years. Recognizing that the Hanford Site has been important to the nation, state, and local community, a task was funded to examine the effects that these activities may have on the historic properties of N Reactor. The objectives of the N Reactor buildings task were to identify potential historic properties at N Reactor, to complete Historic Property Inventory forms for all structures considered eligible and ineligible for listing in the National Register of Historic Places, and to prepare a Memorandum of Agreement that identifies the measures required to mitigate any adverse effects

Study of Some Innovant Reactors without on- Site Refueling with Triso and Cermet Fuel

OpenAIRE

A.Chetaine; A. Benchrif; H. Amsil; V. Kuznetsov; Y. Shimazu

2012-01-01

The evaluation of unit cell neutronic parameters and lifetime for some innovant reactors without on sit-refuling will be held in this work. the behavior of some small and medium reactors without on site refueling with triso and cermet fuel. For the FBNR long life except we propose to change the enrichment of the Cermet MFE to 9%. For the AFPR reactor we can see that the use of the Cermet MFE can extend the life of this reactor but to maintain the same life period for AFPR...

Siting analysis and risk assessment for small single-purpose heating reactors

International Nuclear Information System (INIS)

Tarjanne, R.

1979-04-01

Two alternative sites both 10km away from the centre of Helsinki are considered for reactor unit sizes of 400mw and 800mw. The risks associated with a small single-purpose heating reactor is evaluated for normal operation and accident conditions. The evaluation for accident condition is performed for three characteristics accidents. Three pathways are considered in the calculation of the radiation exposure: direct external gamma dose from the release plume, direct gamma radiation from deposited activity on the ground and dose due to inhalation. The risks are compared with the risks from alternative conventional fossil fuelled district heat production methods. The results show that the heating reactor alternative causes an unsignificant risk, which is far less than the risk caused by the fossil-fuelled alternatives

GRIMH3: A new reactor calculation code at Savannah River Site

International Nuclear Information System (INIS)

Le, T.T.; Pevey, R.E.

1993-01-01

The GRIMHX reactor code currently in use at the Savannah River Site (SRS) was written at a time when computer processing speed and memory storage were very limited. Recently, a new reactor code (GRIMH3) was written to take advantage of the hardware improvements (vectorization and higher memory capacities) as well as the range of available computers at SRS (workstations and supercomputers). The GRIMH3 code computes the solution of the static multigroup neutron diffusion equation in one-, two-, and three-dimensional hexagonal geometry. Either direct or adjoint solutions can be computed for k eff searches, buckling searches, external neutron sources, power flattening searches, or power normalization factor calculations with 1, 6, 24, 54, or 96 points per hex. The GRIMHX reactor code currently in use at the Savannah River Site (SRS) was written at a time when computer processing speed and memory storage were very limited. Recently, a new reactor code (GRIMH3) was written to take advantage of the hardware improvements (vectorization and higher memory capacities) as well as the range of available computers at SRS (workstations and supercomputers). The GRIMH3 code computes the solution of the static multigroup neutron diffusion equation in one-, two-, and three-dimensional hexagonal geometry. Either direct or adjoint solutions can be computed for k eff searches, buckling searches, external neutron sources, power flattening searches, or power normalization factor calculations with 1, 6, 24, 54, or 96 points per hex

Siting of light-water reactor power plants in the Federal Republic of Germany

International Nuclear Information System (INIS)

Kohler, H.A.G.

1975-01-01

The nuclear power plant site requirements formulated for environment protection in Germany allow nuclear power plants to be built at any site provided these requirements are duly taken into account in preparing and monitoring the site and in the design of the proposed power plant. After a brief discussion of light water reactor power plant sites, prevailing practice in site planning, site selection criteria, licensing procedure and used criteria, rules and guidelines, this paper reports on some considerations taken into account by the expert advisers and by the licensing authorities and future site planning. (orig.) [de

Draft environmental impact statement for the siting, construction, and operation of New Production Reactor capacity. Volume 2, Sections 1-6

Energy Technology Data Exchange (ETDEWEB)

1991-04-01

This (EIS) assesses the potential environmental impacts, both on a broad programmatic level and on a project-specific level, concerning a proposed action to provide new tritium production capacity to meet the nation`s nuclear defense requirements well into the 21st century. A capacity equivalent to that of about a 3,000-megawatt (thermal) heavy-water reactor was assumed as a reference basis for analysis in this EIS; this is the approximate capacity of the existing production reactors at DOE`s Savannah River Site. The EIS programmatic alternatives address Departmental decisions to be made on whether to build new production facilities, whether to build one or more complexes, what size production capacity to provide, and when to provide this capacity. Project-specific impacts for siting, constructing, and operating new production reactor capacity are assessed for three alternative sites: the Hanford Site near Richland, Washington; the Idaho National Engineering Laboratory near Idaho Falls, Idaho; and the Savannah River Site. For each site, the impacts of three reactor technologies (and supporting facilities) are assessed: a heavy-water reactor, a light-water reactor, and a modular high-temperature gas-cooled reactor. Impacts of the no-action alternative also are assessed. The EIS evaluates impacts related to air quality; noise levels; surface water, groundwater, and wetlands; land use; recreation; visual environment; biotic resources; historical, archaeological, and cultural resources; socioeconomics; transportation; waste management; and human health and safety. The EIS describes in detail the potential radioactive releases from new production reactors and support facilities and assesses the potential doses to workers and the general public. This volume contains the analysis of programmatic alternatives, project alternatives, affected environment of alternative sites, environmental consequences, and environmental regulations and permit requirements.

Rock siting of nuclear power plants from a reactor safety standpoint

International Nuclear Information System (INIS)

1975-11-01

The study has aimed at surveying the advantages and disadvantages of a rock sited nuclear power plant from a reactor safety standpoint. The studies performed are almost entirely concentrated on the BWR alternative. The design of a nuclear power plant in rock judged most appropriate has been studied in greater detail, and a relatively extensive safety analysis has been made. It is found that the presented technical design of the rock sited alternative is sufficiently advanced to form a basis for further projecting treatment. The chosen technical design of the reactor plant demands a cavern with a 45-50 metre span. Caverns without strengthening efforts with such spans are used in mines, but have no previously been used for industrial plants. Studies of the stability of such caverns show that a safety level is attainable corresponding to the safety required for the other parts of the nuclear power plant. The conditions are that the rock is of high quality, that necessary strengthening measures are taken and that careful studies of the rock are made before and during the blasting, and also during operation of the plant. When locating a rock sited nuclear power plant, the same criteria must be considered as for an above ground plant, with additional stronger demands for rock quality. The presented rock sited nuclear power plant has been assessed to cost 20 % more in total construction costs than a corresponding above ground plant. The motivations for rock siting also depend on whether a condensing plant for only electricity production, or a plant for combined power production and district heating, is considered. The latter would under certain circumstances make rock siting look more attractive. (author)

Mathematical models in Slowpoke reactor internal irradiation site

International Nuclear Information System (INIS)

Raza, J.

2007-01-01

The main objective is to build representative mathematical models of neutron activation analysis in a Slowpoke internal irradiation site. Another significant objective is to correct various elements neutron activation analysis measured mass using these models. The neutron flux perturbation is responsible for the measured under-estimation of real masses. We supposed that neutron flux perturbation measurements taken during the Ecole Polytechnique de Montreal Slowpoke reactor first fuel loading were still valid after the second fuelling. .We also supposed that the thermal neutrons spatial and kinetic energies distributions as well as the absorption microscopic cross section dependence on the neutrons kinetic energies were important factors to satisfactorily represent neutron activation analysis results. In addition, we assumed that the neutron flux is isotropic in the laboratory system. We used experimental results from the Slowpoke reactor internal irradiation sites, in order to validate our mathematical models. Our models results are in close agreement with these experimental results..We established an accurate global mathematical correlation of the neutron flux perturbation in function of samples volumes and macroscopic neutron absorption cross sections. It is applicable to sample volumes ranging from 0,1 to 1,3 ml and macroscopic neutron absorption cross section up to 5 moles-b for seven (7) elements with atomic numbers (Z) ranging from 5 to 79. We first came up with a heuristic neutron transport mathematical semi-analytical model, in order to better understand neutrons behaviour in presence of one of several different nuclei samples volumes and mass. In order to well represent the neutron flux perturbation, we combined a neutron transport solution obtained from the spherical harmonics method of a finite cylinder and a mathematical expression combining two cylindrical harmonic functions..With the help of this model and the least squares method, we made extensive

Nuclear electronic equipment for control and monitoring panel. Procedure guide for on-site tests of nuclear reactor instruments

International Nuclear Information System (INIS)

1975-10-01

By the use of a procedure for on-site testing of nuclear reactor instruments it should be possible to judge their ability to guarantee the reactor safety and availability at the moment of divergence or during operation. Such a procedure must therefore be created as a work implement for the quick and reliable installation of electronic devices necessary for nuclear reactor control and supervision. A standard document is proposed for this purpose, allowing a ''test programme'' to be set up before the equipment is installed on the site [fr

Criteria and measurement techniques applicable to residual radioactivity on a decommissioned reactor site

International Nuclear Information System (INIS)

Woollam, P.B.

1988-12-01

This document summarises the radiological criteria which might be developed to cover the release of a partly decommissioned nuclear reactor site, then looks at the techniques available by which the site could be monitored to assure compliance with these criteria. In particular, the implications of existing levels of radioactive contamination resulting from airburst nuclear weapons tests and the Chernobyl accident are discussed. (author)

Data on loss of off-site electric power simulation tests of the high temperature engineering test reactor

International Nuclear Information System (INIS)

Takeda, Takeshi; Nakagawa, Shigeaki; Fujimoto, Nozomu; Tachibana, Yukio; Iyoku, Tatsuo

2002-07-01

The high temperature engineering test reactor (HTTR), the first high temperature gas-cooled reactor (HTGR) in Japan, achieved the first full power of 30 MW on December 7 in 2001. In the rise-to-power test of the HTTR, simulation tests on loss of off-site electric power from 15 and 30 MW operations were carried out by manual shutdown of off-site electric power. Because helium circulators and water pumps coasted down immediately after the loss of off-site electric power, flow rates of helium and water decreased to the scram points. To shut down the reactor safely, the subcriticality should be kept by the insertion of control rods and the auxiliary cooling system should cool the core continuously avoiding excessive cold shock to core graphite components. About 50 s later from the loss of off-site electric power, the auxiliary cooling system started up by supplying electricity from emergency power feeders. Temperature of hot plenum block among core graphite structures decreased continuously after the startup of the auxiliary cooling system. This report describes sequences of dynamic components and transient behaviors of the reactor and its cooling system during the simulation tests from 15 and 30 MW operations. (author)

Transportation risk assessment of radioactive wastes generated by the N-Reactor stabilization program at the Hanford Site, Washington

International Nuclear Information System (INIS)

Wheeler, T.

1994-12-01

The potential radiological and nonradiological risks associated with specific radioactive waste shipping campaigns at the Hanford Site are estimated. The shipping campaigns analyzed are associated with the transportation of wastes from the N-Reactor site at the 200-W Area, both within the Hanford Reservation, for disposal. The analysis is based on waste that would be generated from the N-Reactor stabilization program

Initiating Events for Multi-Reactor Plant Sites

Energy Technology Data Exchange (ETDEWEB)

Muhlheim, Michael David [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Flanagan, George F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Poore, III, Willis P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2014-09-01

Inherent in the design of modular reactors is the increased likelihood of events that initiate at a single reactor affecting another reactor. Because of the increased level of interactions between reactors, it is apparent that the Probabilistic Risk Assessments (PRAs) for modular reactor designs need to specifically address the increased interactions and dependencies.

Small Reactors without On-site Refuelling: Neutronic Characteristics, Emergency Planning and Development Scenarios. Final Report of an IAEA Coordinated Research Project

International Nuclear Information System (INIS)

2010-09-01

Small reactors without on-site refuelling have a capability to operate without reloading or shuffling of fuel in their cores for reasonably long periods of time consistent with plant economy and considerations of energy security, with no fresh or spent fuel being stored at the site during reactor operation. In 2009, more than 25 design concepts of such reactors were analyzed or developed in IAEA Member States, representing both developed and developing countries. Small reactors without on-site refuelling are being developed for several reactor lines, including water cooled reactors, sodium cooled fast reactors, lead and lead bismuth cooled reactors, and also include some non-conventional concepts. Most of the concepts of small reactors without on-site refuelling reactors are at early design stages. To make such reactors viable, further research and development (R and D) is necessary, inter alia, to validate long-life core operation, define and validate new robust types of fuel, justify an option of plant location in the proximity to its users, and examine possible niches that such reactors could fill in future energy systems. To further research and development (R and D) in the areas mentioned above and several others, and to facilitate progress in Member States in design and technology development for small reactors without on-site refueling, the IAEA has conducted a dedicated Coordinated Research Project (CRP) entitled 'Small Reactors without On-site Refuelling' (CRPi25001). The project started late in 2004 and, after a review in 2008, was extended for one more year to be ended in 2009. The project has created a network of 18 research institutions from 10 Member States, representing both developed and developing countries. Over the CRP period, collaborative results were achieved for many of the abovementioned research areas. Some studies highlighted new directions of research to be furthered after the CRP completion. Some studies remained the efforts of

Decommissioning the Jason Argonaut research reactor at a world heritage site

Energy Technology Data Exchange (ETDEWEB)

Lockwood, R.J.S.; Beeley, P.A. [HMS Sultan, Gosport, Hampshire (United Kingdom)

2001-07-01

The Jason low power Argonaut type, water and graphite moderated reactor was located in King William Building, which is a Grade 1 listed building within the Royal Naval College, Greenwich, London. The College itself is a Scheduled Ancient Monument with World Heritage Site status and is situated about a mile from the Greenwich Dome. The decision to decommission Jason to International Atomic Energy Agency Stage 3 status (unrestricted site use) was taken in 1996. All physical decommissioning work was completed by October 1999, site radiological clearance was obtained in November 1999, the site license was withdrawn and the site was handed over for future unrestricted use on 9 December 1999. The Jason decommissioning project was safely completed to time, cost and quality by the Millennium [2] without any adverse effects on World Heritage aspects of the site. In this paper details are provided about the Jason fuel removal phase and an outline of the other phases of the project.

Siting considerations for radioactivity in reactor effluents during normal operation

International Nuclear Information System (INIS)

Graf, J.M.; Strom, P.O.

1975-01-01

In selecting a proper site for a nuclear power station, the consideration of radioactivity released in effluents can be handled in a straightforward manner using the U. S. Atomic Energy Commission's proposed Appendix I to 10 CFR 50, which gives numerical guidelines for design objectives for meeting the criterion ''as low as practicable'' for radioactive material in light-water-cooled nuclear power reactor effluents. By relating the release of radioactive material, the site meteorological conditions, and site boundary distance through appropriate dose models, the suitability of a given site can be determined. ''Rules of thumb'' for comparing anticipated releases to design objectives can be constructed for rapid assessment using the maximum permissible concentration values of 10 CFR 20 as dose factors. These rules of thumb tend to underpredict the allowed releases except in the case of radiocesium in liquids. For gaseous releases, these rules of thumb can be made up in convenient nomogram form for a quick assessment of allowed releases based on local site meteorological conditions. (U.S.)

Review of Savannah River Site K Reactor inservice inspection and testing restart program

International Nuclear Information System (INIS)

Anderson, M.T.; Hartley, R.S.; Kido, C.

1992-09-01

Inservice inspection (ISI) and inservice testing (IST) programs are used at commercial nuclear power plants to monitor the pressure boundary integrity and operability of components in important safety-related systems. The Department of Energy (DOE) - Office of Defense Programs (DP) operates a Category A (> 20 MW thermal) production reactor at the Savannah River Site (SRS). This report represents an evaluation of the ISI and IST practices proposed for restart of SRS K Reactor as compared, where applicable, to current ISI/IST activities of commercial nuclear power facilities

Seismic hazard analysis for the NTS spent reactor fuel test site

International Nuclear Information System (INIS)

Campbell, K.W.

1980-01-01

An experiment is being directed at the Nevada Test Site to test the feasibility for storage of spent fuel from nuclear reactors in geologic media. As part of this project, an analysis of the earthquake hazard was prepared. This report presents the results of this seismic hazard assessment. Two distinct components of the seismic hazard were addressed: vibratory ground motion and surface displacement

Proceedings of the CNRA Workshop on New Reactor Siting, Licensing and Construction Experience

International Nuclear Information System (INIS)

2011-01-01

This report documents the proceedings from the 'Workshop on New Reactor Siting, Licensing and Construction Experience', held in Prague, Czech Republic on 15-17 September 2010. A total of 59 specialists from 16 countries and international organisations attended. The Meeting was sponsored by the OECD Nuclear Energy Agency Committee on Nuclear Regulatory Activities and hosted by the State Office for Nuclear Safety (SUJB) in Czech Republic. The objectives of the workshop were to review and discuss recent and past construction experience lessons learned including perspectives from regulatory authorities, as well as vendors, and licensee. The workshop addressed issues associated with project management resources including: a) overall human resources, expertise, experience and organisation available to the licensee, b) capability of each potential vendor (in-house knowledge and skills versus planned subcontracting and subcontractor management). The workshop also discussed the lessons learned in the regulation of site selection, evaluation and site preparation as well as the review of regulatory practices for the licensing of new reactors, including the regulatory body infrastructure, staffing and expertise needed. The workshop provided an excellent opportunity to communicate recent experience on these topics to a wider audience, including participants from OECD member countries as well as New Entrants from non-OECD member countries. The workshop allowed the WGRNR group to introduce and discuss the current programme of work and products under development in order to gain insights from workshop participants on each of the programme of work areas, and get feedback on additional focus areas. The workshop was structured in 4 technical sessions, each followed by ample time for panel discussions. The first technical session was devoted to presentations of the licensing process for new reactors followed by different member countries. The second technical session was

SAVANNAH RIVER SITE R REACTOR DISASSEMBLY BASIN IN SITU DECOMMISSIONING

Energy Technology Data Exchange (ETDEWEB)

Langton, C.; Blankenship, J.; Griffin, W.; Serrato, M.

2009-12-03

The US DOE concept for facility in-situ decommissioning (ISD) is to physically stabilize and isolate in tact, structurally sound facilities that are no longer needed for their original purpose of, i.e., generating (reactor facilities), processing(isotope separation facilities) or storing radioactive materials. The 105-R Disassembly Basin is the first SRS reactor facility to undergo the in-situ decommissioning (ISD) process. This ISD process complies with the105-R Disassembly Basin project strategy as outlined in the Engineering Evaluation/Cost Analysis for the Grouting of the R-Reactor Disassembly Basin at the Savannah River Site and includes: (1) Managing residual water by solidification in-place or evaporation at another facility; (2) Filling the below grade portion of the basin with cementitious materials to physically stabilize the basin and prevent collapse of the final cap - Sludge and debris in the bottom few feet of the basin will be encapsulated between the basin floor and overlying fill material to isolate if from the environment; (3) Demolishing the above grade portion of the structure and relocating the resulting debris to another location or disposing of the debris in-place; and (4) Capping the basin area with a concrete slab which is part of an engineered cap to prevent inadvertent intrusion. The estimated total grout volume to fill the 105-R Reactor Disassembly Basin is 24,424 cubic meters or 31,945 cubic yards. Portland cement-based structural fill materials were design and tested for the reactor ISD project and a placement strategy for stabilizing the basin was developed. Based on structural engineering analyses and work flow considerations, the recommended maximum lift height is 5 feet with 24 hours between lifts. Pertinent data and information related to the SRS 105-R-Reactor Disassembly Basin in-situ decommissioning include: regulatory documentation, residual water management, area preparation activities, technology needs, fill material designs

A model for the calculation of the off-site economic consequences of nuclear reactor accidents

International Nuclear Information System (INIS)

Gallego, E.; Alonso, A.

1988-01-01

The off-site economic cost of nuclear reactor accidents will depend on the countermeasures adopted to reduce its radiological impact. The assessment of the direct costs of emergency countermeasures (evacuation, early relocation and food disposal) as well as those of long-term protective actions (food disposal, decontamination or interdiction) is the objective of a model under development, with the sponsorship of the CEC Radiation Protection Programme, called MECA (Model for assessing the Economic Consequences of Accidents). The meteorological and socio-economical peculiarities of each site studied will be taken into account, by means of a flexible meteorological sampling scheme, which considers the geographical distribution of population and economic centers, and a data-base, compatible with the existing European grid, that contains the population distribution and the economic characteristics of the environs of the site to be studied with more detail near the reactor. The paper summarizes the particular models which will be included in MECA and shows the importance of site-specific adaptable modelling for economic risk evaluation

Draft environmental impact statement for the siting, construction, and operation of New Production Reactor capacity. Volume 3, Sections 7-12, Appendices A-C

Energy Technology Data Exchange (ETDEWEB)

1991-04-01

This Environmental Impact Statement (EIS) assesses the potential environmental impacts, both on a broad programmatic level and on a project-specific level, concerning a proposed action to provide new tritium production capacity to meet the nation`s nuclear defense requirements well into the 21st century. A capacity equivalent to that of about a 3,000-megawatt (thermal) heavy-water reactor was assumed as a reference basis for analysis in this EIS; this is the approximate capacity of the existing production reactors at DOE`s Savannah River Site near Aiken, South Carolina. The EIS programmatic alternatives address Departmental decisions to be made on whether to build new production facilities, whether to build one or more complexes, what size production capacity to provide, and when to provide this capacity. Project-specific impacts for siting, constructing, and operating new production reactor capacity are assessed for three alternative sites: the Hanford Site near Richland, Washington; the Idaho National Engineering Laboratory near Idaho Falls, Idaho; and the Savannah River Site. For each site, the impacts of three reactor technologies (and supporting facilities) are assessed: a heavy-water reactor, a light-water reactor, and a modular high-temperature gas-cooled reactor. Impacts of the no-action alternative also are assessed. The EIS evaluates impacts related to air quality; noise levels; surface water, groundwater, and wetlands; land use; recreation; visual environment; biotic resources; historical, archaeological, and cultural resources; socioeconomics; transportation; waste management; and human health and safety. The EIS describes in detail the potential radioactive releases from new production reactors and support facilities and assesses the potential doses to workers and the general public. This volume contains references; a list of preparers and recipients; acronyms, abbreviations, and units of measure; a glossary; an index and three appendices.

External events analysis for the Savannah River Site K reactor

International Nuclear Information System (INIS)

Brandyberry, M.D.; Wingo, H.E.

1990-01-01

The probabilistic external events analysis performed for the Savannah River Site K-reactor PRA considered many different events which are generally perceived to be ''external'' to the reactor and its systems, such as fires, floods, seismic events, and transportation accidents (as well as many others). Events which have been shown to be significant contributors to risk include seismic events, tornados, a crane failure scenario, fires and dam failures. The total contribution to the core melt frequency from external initiators has been found to be 2.2 x 10 -4 per year, from which seismic events are the major contributor (1.2 x 10 -4 per year). Fire initiated events contribute 1.4 x 10 -7 per year, tornados 5.8 x 10 -7 per year, dam failures 1.5 x 10 -6 per year and the crane failure scenario less than 10 -4 per year to the core melt frequency. 8 refs., 3 figs., 5 tabs

Reactor safety under design basis flood condition for inland sites

International Nuclear Information System (INIS)

Hajela, S.; Bajaj, S.S.; Samota, A.; Verma, U.S.P.; Warudkar, A.S.

2002-01-01

Full text: In June 1994, there was an incident of flooding at Kakrapar Atomic Power Station (KAPS) due to combination of heavy rains and mechanical failure in the operation of gates at the adjoining weir. An indepth review of the incident was carried out and a number of flood protection measures were recommended and were implemented at site. As part of this review, a safety analysis was also done to demonstrate reactor safety with a series of failures considered in the flood protection features. For each inland NPP site, as part of design, different flood scenarios are analysed to arrive at design basis flood (DBF) level. This level is estimated based on worst combination of heavy local precipitation, flooding in river, failure of upstream/downstream water control structures

Investigation of reactivity changes due to flooding the irradiation sites of the MNSR reactor using the MCNP code and comparison with experimental results

Directory of Open Access Journals (Sweden)

A Shirani

2010-06-01

Full Text Available In this work, the Isfahan Miniature Neutron Source Reactor (MNSR has been simulated using the MCNP code, and reactivity worth of flooding the inner irradiation sites of this reactor in an accident has been calculated. Also, by inserting polyethylene capsules containing water inside the inner irradiation sites, reactivity changes of this reactor in same such accident have been measured, the results of which are in good agreements with the calculated results. In this work, the reactivity worth due to flooding one inner irradiation site is 0.53mk , and reactivity worth due to flooding of the whole 5 inner irradiation sites is 2.61 mk.

On-site emergency intervention plan for nuclear accident situation at SCN-Pitesti TRIGA Reactor

International Nuclear Information System (INIS)

Margeanu, S.; Oprea, I.

2008-01-01

A 14 MW TRIGA research reactor is operated on the Institute for Nuclear Research site. In the event of a nuclear accident or radiological emergency that may affect the public the effectiveness of protective actions depends on the adequacy of intervention plans prepared in advance. Considerable planning is necessary to reduce to manageable levels the types of decisions leading to effective responses to protect the public in such an event. The essential structures of our on-site, off-site and county emergency intervention plan and the correlation between emergency intervention plans are presented. (authors)

Preliminary Geological Survey on the Proposed Sites for the New Research Reactor

International Nuclear Information System (INIS)

Lim, In Cheol; Ha, J. J.; Oh, K. B.

2010-12-01

· Performing the preliminary geological survey on the proposed sites for the new research reactor through the technical service · Ordering a technical service from The Geological Society of Korea · Contents of the geological survey - Confirmation of active fault - Confirmation of a large-scale fracture zone or weak zone - Confirmation of inappropriate items related to the underground water - Confirmation of historical seismicity and instrumental earthquakes data · Synthesized analysis and holding a report meeting · Results of the geological survey - Confirmation of the geological characteristics of the sites and drawing the requirements for the precise geological survey in the future

ELECTRICAL RESISTANCE HEATING OF SOILS AT C-REACTOR AT THE SAVANNAH RIVER SITE

International Nuclear Information System (INIS)

Blundy, R; Michael Morgenstern, M; Joseph Amari, J; Annamarie MacMurray, A; Mark Farrar, M; Terry Killeen, T

2007-01-01

Chlorinated solvent contamination of soils and groundwater is an endemic problem at the Savannah River Site (SRS), and originated as by-products from the nuclear materials manufacturing process. Five nuclear reactors at the SRS produced special nuclear materials for the nation's defense program throughout the cold war era. An important step in the process was thorough degreasing of the fuel and target assemblies prior to irradiation. Discharges from this degreasing process resulted in significant groundwater contamination that would continue well into the future unless a soil remediation action was performed. The largest reactor contamination plume originated from C-Reactor and an interim action was selected in 2004 to remove the residual trichloroethylene (TCE) source material by electrical resistance heating (ERH) technology. This would be followed by monitoring to determine the rate of decrease in concentration in the contaminant plume. Because of the existence of numerous chlorinated solvent sources around SRS, it was elected to generate in-house expertise in the design and operation of ERH, together with the construction of a portable ERH/SVE system that could be deployed at multiple locations around the site. This paper describes the waste unit characteristics, the ERH system design and operation, together with extensive data accumulated from the first deployment adjacent to the C-Reactor building. The installation heated the vadose zone down to 62 feet bgs over a 60 day period during the summer of 2006 and raised soil temperatures to over 200 F. A total of 730 lbs of trichloroethylene (TCE) were removed over this period, and subsequent sampling indicated a removal efficiency of 99.4%

Environmental Assessment: Relocation and storage of TRIGA reg-sign reactor fuel, Hanford Site, Richland, Washington

International Nuclear Information System (INIS)

1995-08-01

In order to allow the shutdown of the Hanford 308 Building in the 300 Area, it is proposed to relocate fuel assemblies (101 irradiated, three unirradiated) from the Mark I TRIGA Reactor storage pool. The irradiated fuel assemblies would be stored in casks in the Interim Storage Area in the Hanford 400 Area; the three unirradiated ones would be transferred to another TRIGA reactor. The relocation is not expected to change the offsite exposure from all Hanford Site 300 and 400 Area operations

On-site releases of noble gases and iodine in the event of core meltdown in a swimming pool reactor

International Nuclear Information System (INIS)

Montaignac, E. de.

1976-10-01

Research aimed at defining a standard model accident for swimming pool type reactors, has led to the adoption to the so-called BORAX accident which involves complete meltdown of the reactor core. This type of accident-an accident related to dimensional problems- is useful for calculations concerning reactor components which have to withstand the mechanical forces resulting from the accident. A study of the radiobiological consequences of this type of accident, involving the entire reactor core, required research to determine as accurately as possible how the iodine, noble gases and solid fission products are distributed between the melted core and the site. The joint document in the annexure served as the basis for discussion at the meeting (BEVS/SESR) on 9th March 1973, at which the SESR set the standard parameter values to be used for estimating fission product distributions on the site. (author)

Record of Decision; Continued operation of K, L, and P Reactors, Savannah River Site, Aiken, South Carolina

International Nuclear Information System (INIS)

1991-01-01

The US Department of Energy (DOE) has considered the environmental impacts, benefits and costs, and institutional and programmatic needs associated with continued operation of the Savannah River Site (SRS) reactors, and has decided that it will continue to operate K and L Reactors at SRS, and will terminate operation of P Reactor in the immediate future and maintain it in cold standby. For P Reactor, this will involve the reactor's defueling; storage of its heavy water moderator in tanks in the reactor building; shutdown of reactor equipment and systems in a protected condition to prevent deterioration; and maintenance of the reactor in a defueled, protected status by a skeleton staff, which would permit any future decision to refuel and restart. Currently committed and planned upgrade activities will be discontinued for P Reactor. DOE will proceed with the safety upgrades and management system improvements currently scheduled for K Reactor in its program to satisfy the criteria of the Safety Evaluation Report (SER), and will conduct an Operational Readiness Review (ORR). The satisfaction of the SER criteria and completion of the ORR will demonstrate that the safety and health criteria for the resumption of production have been met. Reactor restart is expected to be in the third quarter of 1991 for K Reactor

Processing Tritiated Water at the Savannah River Site: A Production-Scale Demonstration of a palladium membrane reactor

International Nuclear Information System (INIS)

Sessions, K

2004-01-01

The Palladium Membrane Reactor (PMR) process was installed in the Tritium Facilities at the Savannah River Site to perform a production-scale demonstration for the recovery of tritium from tritiated water adsorbed on molecular sieve (zeolite). Unlike the current recovery process that utilizes magnesium, the PMR offers a means to process tritiated water in a more cost effective and environmentally friendly manner. The design and installation of the large-scale PMR process was part of a collaborative effort between the Savannah River Site and Los Alamos National Laboratory. The PMR process operated at the Savannah River Site between May 2001 and April 2003. During the initial phase of operation the PMR processed thirty-four kilograms of tritiated water from the Princeton Plasma Physics Laboratory. The water was processed in fifteen separate batches to yield approximately 34,400 liters (STP) of hydrogen isotopes. Each batch consisted of round-the-clock operations for approximately nine days. In April 2003 the reactor's palladium-silver membrane ruptured resulting in the shutdown of the PMR process. Reactor performance, process performance and operating experiences have been evaluated and documented. A performance comparison between PMR and current magnesium process is also documented

Preoperational environmental monitoring of the Angra reactor site

International Nuclear Information System (INIS)

Mendonca, A.H.; Nobrega, A.W.; Mulder, R.U.; Vianna, M.E.C.; Almeida, C.E. de; Winter, M.

1983-03-01

The Preoperational Environmental Monitoring Program for the Angra Nuclear power plant site as well as the single and summarized results obtained this program are presented and discussed in this report. For clarity, a description is given of the Angra site and of the program structure and a map of the region showing measurement and sampling locations is included. Preoperational monitoring was carried out over the period from September 1979 to September 1981. For direct measurements of background radiation levels a solid-state dosimeter network was used and the results were compared to measurements made with ionization chambers. Measurements were performed of natural and artificial radioactivity concentration levels in air, surface water, soil, grass, sea sediments, sea algae and various foodstuffs. Gross alpha and beta activity levels were determined as well as the concentration levels of individual natural radionuclides. The presence of cesium-137 originating from fallout was observed in manioc. Minimum detection limits for fission and activated corrosion products which are of interest during the reactor operational period were defined and determined for the instrumentation and methods used at the Institute of Radioprotection and Dosimetry. These limits have been included in the tables. (Author) [pt

SAVANNAH RIVER SITE R-REACTOR DISASSEMBLY BASIN IN-SITU DECOMMISSIONING -10499

Energy Technology Data Exchange (ETDEWEB)

Langton, C.; Serrato, M.; Blankenship, J.; Griffin, W.

2010-01-04

The US DOE concept for facility in-situ decommissioning (ISD) is to physically stabilize and isolate intact, structurally sound facilities that are no longer needed for their original purpose, i.e., generating (reactor facilities), processing(isotope separation facilities) or storing radioactive materials. The 105-R Disassembly Basin is the first SRS reactor facility to undergo the in-situ decommissioning (ISD) process. This ISD process complies with the 105-R Disassembly Basin project strategy as outlined in the Engineering Evaluation/Cost Analysis for the Grouting of the R-Reactor Disassembly Basin at the Savannah River Site and includes: (1) Managing residual water by solidification in-place or evaporation at another facility; (2) Filling the below grade portion of the basin with cementitious materials to physically stabilize the basin and prevent collapse of the final cap - Sludge and debris in the bottom few feet of the basin will be encapsulated between the basin floor and overlying fill material to isolate it from the environment; (3) Demolishing the above grade portion of the structure and relocating the resulting debris to another location or disposing of the debris in-place; and (4) Capping the basin area with a concrete slab which is part of an engineered cap to prevent inadvertent intrusion. The estimated total grout volume to fill the 105-R Reactor Disassembly Basin is 24,384 cubic meters or 31,894 cubic yards. Portland cement-based structural fill materials were designed and tested for the reactor ISD project, and a placement strategy for stabilizing the basin was developed. Based on structural engineering analyses and material flow considerations, maximum lift heights and differential height requirements were determined. Pertinent data and information related to the SRS 105-R Reactor Disassembly Basin in-situ decommissioning include: regulatory documentation, residual water management, area preparation activities, technology needs, fill material

Safety Evaluation Report Restart of K-Reactor Savannah River Site

International Nuclear Information System (INIS)

1991-10-01

In April 1991, the Department of Energy (DOE) issued DOE/DP-0084T, ''Safety Evaluation Report Restart of K-Reactor Savannah River Site.'' The Safety Evaluation Report (SER) documents the results of DOE reviews and evaluations of the programmatic aspects of a large number of issues necessary to be satisfactorily addressed before restart. The issues were evaluated for compliance with the restart criteria included in the SER. The results of those evaluations determined that the restart criteria had been satisfied for some of the issues. However, for most of the issues at least part of the applicable restart criteria had not been found to be satisfied at the time the evaluations were prepared. For those issues, open or confirmatory items were identified that required resolution. In August 1991, DOE issued DOE/DP-0090T, ''Safety Evaluation Report Restart of K-Reactor Savannah River Site Supplement 1.'' That document was the first Supplement to the April 1991 SER, and documented the resolution of 62 of the open items identified in the SER. This document is the second Supplement to the April 1991 SER. This second SER Supplement documents the resolution of additional open times identified in the SER, and includes a complete list of all remaining SER open items. The resolution of those remaining open items will be documented in future SER Supplements. Resolution of all open items for an issue indicates that its associated restart criteria have been satisfied, and that DOE concludes that the programmatic aspects of the issue have been satisfactorily addressed

Survey of radiological contaminants in the near-shore environment at the Hanford Site 100-N Area reactor

International Nuclear Information System (INIS)

Van Verst, S.P.; Albin, C.L.; Patton, G.W.; Blanton, M.L.; Poston, T.M.; Cooper, A.T.; Antonio, E.J.

1998-09-01

Past operations at the Hanford Site 100-N Area reactor resulted in the release of radiological contaminants to the soil column, local groundwater, and ultimately to the near-shore environment of the Columbia River. In September 1997, the Washington State Department of Health (WDOH) and the Hanford Site Surface Environmental Surveillance Project (SESP) initiated a special study of the near-shore vicinity at the Hanford Site's retired 100-N Area reactor. Environmental samples were collected and analyzed for radiological contaminants ( 3 H, 90 Sr, and gamma/ emitters), with both the WDOH and SESP analyzing a portion of the samples. Samples of river water, sediment, riverbank springs, periphyton, milfoil, flying insects, clam shells, and reed canary grass were collected. External exposure rates were also measured for the near-shore environment in the vicinity of the 100-N Area. In addition, samples were collected at background locations above Vernita Bridge

Stationary low power reactor No. 1 (SL-1) accident site decontamination ampersand dismantlement project

International Nuclear Information System (INIS)

Perry, E.F.

1995-01-01

The Army Reactor Area (ARA) II was constructed in the late 1950s as a test site for the Stationary Low Power Reactor No. 1 (SL-1). The SL-1 was a prototype power and heat source developed for use at remote military bases using a direct cycle, boiling water, natural circulation reactor designed to operate at a thermal power of 3,000 kW. The ARA II compound encompassed 3 acres and was comprised of (a) the SL-1 Reactor Building, (b) eight support facilities, (c) 50,000-gallon raw water storage tank, (d) electrical substation, (e) aboveground 1,400-gallon heating oil tank, (f) underground 1,000-gallon hazardous waste storage tank, and (g) belowground power, sewer, and water systems. The reactor building was a cylindrical, aboveground facility, 39 ft in diameter and 48 ft high. The lower portion of the building contained the reactor pressure vessel surrounded by gravel shielding. Above the pressure vessel, in the center portion of the building, was a turbine generator and plant support equipment. The upper section of the building contained an air cooled condenser and its circulation fan. The major support facilities included a 2,500 ft 2 two story, cinder block administrative building; two 4,000 ft 2 single story, steel frame office buildings; a 850 ft 2 steel framed, metal sided PL condenser building, and a 550 ft 2 steel framed decontamination and laydown building

Nuclear power reactors: reactor safety and military and civil defence

International Nuclear Information System (INIS)

Hvinden, T.

1976-01-01

The formation of fission products and plutonium in reactors is briefly described, followed by a short general discussion of reactor safety. The interaction of reactor safety and radioactive release considerations with military and civil defence is thereafter discussed. Reactors and other nuclear plants are factors which must be taken into account in the defence of the district around the site, and as potential targets of both conventional and guerilla attacks and sabotage, requiring special defence. The radiological hazards arising from serious damage to a power reactor by conventional weapons are briefly discussed, and the benefits of underground siting evaluated. Finally the author discusses the significance of the IAEA safeguards work as a preventive factor. (JIW)

Upgrade of the Department of Energy's Savannah River Site's reactor operations and maintenance procedures

International Nuclear Information System (INIS)

Walsh, T.E.

1991-01-01

This paper describes the program in progress at the Savannah River Site (SRS) to upgrade the existing reactor operating and maintenance procedures to current commercial nuclear industry standards. In order to meet this goal, the following elements were established: administrative procedures to govern the upgrade process, tracking system to provide status and accountability; and procedure writing guides. The goal is to establish a benchmark of excellence by which other Department of Energy (DOE) sites will measure themselves. The above three elements are addressed in detail in this paper

On-site underground background measurements for the KASKA reactor-neutrino experiment

International Nuclear Information System (INIS)

Furuta, H.; Sakuma, K.; Aoki, M.; Fukuda, Y.; Funaki, Y.; Hara, T.; Haruna, T.; Ishihara, N.; Katsumata, M.; Kawasaki, T.; Kuze, M.; Maeda, J.; Matsubara, T.; Matsumoto, T.; Miyata, H.; Nagasaka, Y.; Nakagawa, T.; Nakajima, N.; Nitta, K.; Sakai, K.; Sakamoto, Y.; Suekane, F.; Sumiyoshi, T.; Tabata, H.; Tamura, N.; Tsuchiya, Y.

2006-01-01

On-site underground background measurements were performed for the planned reactor-neutrino oscillation experiment KASKA at Kashiwazaki-Kariwa nuclear power station in Niigata, Japan. A small-diameter boring hole was excavated down to 70m underground level, and a detector unit for γ-ray and cosmic-muon measurements was placed at various depths to take data. The data were analyzed to obtain abundance of natural radioactive elements in the surrounding soil and rates of cosmic muons that penetrate the overburden. The results will be reflected in the design of the KASKA experiment

Numerical and on-site experimental dynamic analysis of the Italian PEC fast reactor building

International Nuclear Information System (INIS)

Castoldi, A.; Muzzi, F.; Orsi, R.; Panzeri, P.; Pezzoli, P.; Ruggeri, G.; Martelli, A.; Masoni, P.; Brancati, V.

1988-01-01

On-site dynamic tests and three-dimensional numerical analysis have been performed by ISMES on behalf of ENEA on the building of the Italian PEC fast reactor test facility. These studies aimed at evaluating the safety margins in the PEC reactor seismic analysis and at providing data for the optimization of the PEC seismic monitoring system. The paper describes the on-site dynamic tests carried out using various excitation methods (two eccentric back-rotating-mass mechanical vibrator, blasting in bore-hole and hydraulic actuators at the building foundations). It highlights the purposes of the four tests campaigns performed at various construction stages and reports the main experimental results. In connection with the experimental tests, a detailed 3D finite element model was set up for fixed base analysis; from the results of the 3D model a simplified equivalent model of the structure was then derived for soil-structure interaction analysis. The mathematical model was validated and calibrated by using the results of the experimental dynamic tests. The main numerical results and the comparisons with the experimental data are presented. (author)

Description of the two-loop RELAP5 model of the L-Reactor at the Savannah River Site

International Nuclear Information System (INIS)

Cozzuol, J.M.; Davis, C.B.

1989-12-01

A two-loop RELAP5 input model of the L-Reactor at the Savannah River Site (SRS) was developed to support thermal-hydraulic analysis of SRS reactors. The model was developed to economically evaluate potential design changes. The primary simplifications in the model were in the number of loops and the detail in the moderator tank. The six loops in the reactor were modeled with two loops, one representing a single loop and the other representing five combined loops. The model has undergone a quality assurance review. This report describes the two-loop model, its limitations, and quality assurance. 29 refs., 18 figs., 10 tabs

Design guide for Category III reactors: pool type reactors

International Nuclear Information System (INIS)

Brynda, W.J.; Lobner, P.R.; Powell, R.W.; Straker, E.A.

1978-11-01

The Department of Energy (DOE) in the ERDA Manual requires that all DOE-owned reactors be sited, designed, constructed, modified, operated, maintained, and decommissioned in a manner that gives adequate consideration to health and safety factors. Specific guidance pertinent to the safety of DOE-owned reactors is found in Chapter 0540 of the ERDA Manual. The purpose of this Design Guide is to provide additional guidance to aid the DOE facility contractor in meeting the requirement that the siting, design, construction, modification, operation, maintenance, and decommissioning of DOE-owned reactors be in accordance with generally uniform standards, guides, and codes which are comparable to those applied to similar reactors licensed by the Nuclear Regulatory Commission (NRC). This Design Guide deals principally with the design and functional requirement of Category III reactor structures, components, and systems

Transportation infrastructure upgrades in the South: A compilation of state plans for construction near nuclear reactor sites

International Nuclear Information System (INIS)

1992-03-01

There are currently 27 nuclear reactor sites located in the southern region. In many instances, the most practicable modes of transportation of spent nuclear fuel from these sites we through the use of highway and rail systems. These two transportation modes have important differences that affect their applicability; chief among these, perhaps, is the fact that while highway systems are publicly owned and maintained rail lines are owned by private entities. For this reason, track condition and maintenance, usage rates and other aspects of rail transport can vary widely. This report reviews southern state, department plans for infrastructure upgrades in the vicinity of nuclear reactor sites. This report includes a summary of planned modifications to bridges, access highways, and rail spurs (where applicable) over the next five years. The information contained herein was gathered from interviews with officials within state departments of transportation. With few exceptions, the contact person was an official within the departmental planning division

Using SAFRAN Software to Assess Radiological Hazards from Dismantling of Tammuz-2 Reactor Core at Al-tuwaitha Nuclear Site

Science.gov (United States)

Abed Gatea, Mezher; Ahmed, Anwar A.; jundee kadhum, Saad; Ali, Hasan Mohammed; Hussein Muheisn, Abbas

2018-05-01

The Safety Assessment Framework (SAFRAN) software has implemented here for radiological safety analysis; to verify that the dose acceptance criteria and safety goals are met with a high degree of confidence for dismantling of Tammuz-2 reactor core at Al-tuwaitha nuclear site. The activities characterizing, dismantling and packaging were practiced to manage the generated radioactive waste. Dose to the worker was considered an endpoint-scenario while dose to the public has neglected due to that Tammuz-2 facility is located in a restricted zone and 30m berm surrounded Al-tuwaitha site. Safety assessment for dismantling worker endpoint-scenario based on maximum external dose at component position level in the reactor pool and internal dose via airborne activity while, for characterizing and packaging worker endpoints scenarios have been done via external dose only because no evidence for airborne radioactivity hazards outside the reactor pool. The in-situ measurements approved that reactor core components are radiologically activated by Co-60 radioisotope. SAFRAN results showed that the maximum received dose for workers are (1.85, 0.64 and 1.3mSv/y) for activities dismantling, characterizing and packaging of reactor core components respectively. Hence, the radiological hazards remain below the low level hazard and within the acceptable annual dose for workers in radiation field

2016 Inspection and Annual Site Status Report for the Site A/Plot M, Illinois, Decommissioned Reactor Site July 2016

Energy Technology Data Exchange (ETDEWEB)

Murl, Jeffrey [USDOE Office of Legacy Management, Washington, DC (United States); Miller, Michele [Navarro Research and Engineering, Oak Ridge, TN (United States)

2016-07-01

The Site A/Plot M, Illinois, Decommissioned Reactor Site was inspected on May 17, 2016. The site, located within Cook County forest preserve that is open to the public, was found to be in good condition with one exception. Erosion on top of the grass-covered mound at Plot M continues to be a concern as presented in previous inspections. Ruts form in the soil on top of Plot M as a result of bike traffic using the open field as a pass thru between established bike trails within the forest preserve. Argonne National Laboratory (ANL) who is contracted directly from U.S. Department of Energy (DOE) has filled in the ruts with top soil and reseeding remains an ongoing process. Reseeded areas from 2015 are progressing nicely. No cause for a follow-up inspection was identified. In 2015, ANL plugged and abandoned 8 of 25 monitoring wells (BH41, BH51, BH52, BH54, DH9, DH10, DH13, and DH17). The 17 groundwater monitoring wells remaining at the site were inspected to confirm that they were locked and in good condition. Preliminary environmental monitoring results for 2015 are provided in a draft report titled Surveillance of Site A and Plot M, Report for 2015, prepared by ANL. The report also contains results of an independent analysis conducted by the Illinois Emergency Management Agency on some of the samples collected by ANL in 2015. The draft report states that the results of the surveillance program continue to indicate that the impact of radioactivity at Site A/Plot M is very low and does not endanger the health of those living in the area or visiting the site. The ANL monitoring report will be made available to the public on the DOE Office of Legacy Management public website when it is issued as final. A new county forest preserve campsite opened in 2015 at Bull Frog Lake, which is east of Plot M. Hiking trails connect Bull Frog Lake with Site A/Plot M. The site might receive more traffic from forest preserve visitors now that this new campsite is opened.

The UASB reactor as an alternative for the septic tank for on-site sewage treatment.

Science.gov (United States)

Coelho, A L S S; do Nascimento, M B H; Cavalcanti, P F F; van Haandel, A C

2003-01-01

Although septic tanks are amply used for on site sewage treatment, these units have serious drawbacks: the removal efficiency of organic material and suspended solids is low, the units are costly and occupy a large area and operational cost is high due to the need for periodic desludging. In this paper an innovative variant of the UASB reactor is proposed as an alternative for the septic tank. This alternative has several important advantages in comparison with the conventional septic tank: (1) Although the volume of the UASB reactor was about 4 times smaller than the septic tank, its effluent quality was superior, even though small sludge particles were present, (2) desludging of the UASB reactor is unnecessary and even counterproductive, as the sludge mass guarantees proper performance, (3) the UASB reactor is easily transportable (compact and light) and therefore can be produced in series, strongly reducing construction costs and (4) since the concentration of colloids in the UASB effluent is much smaller than in the ST effluent, it is expected that the infiltration of the effluent will be much less problematic.

Reactor safeguards

CERN Document Server

Russell, Charles R

1962-01-01

Reactor Safeguards provides information for all who are interested in the subject of reactor safeguards. Much of the material is descriptive although some sections are written for the engineer or physicist directly concerned with hazards analysis or site selection problems. The book opens with an introductory chapter on radiation hazards, the construction of nuclear reactors, safety issues, and the operation of nuclear reactors. This is followed by separate chapters that discuss radioactive materials, reactor kinetics, control and safety systems, containment, safety features for water reactor

Renewal of reactor cooling system of JMTR. Reactor building site

International Nuclear Information System (INIS)

Onoue, Ryuji; Kawamata, Takanori; Otsuka, Kaoru; Sekine, Katsunori; Koike, Sumio; Gorai, Shigeru; Nishiyama, Yutaka; Fukasaku, Akitomi

2012-03-01

The Japan Materials Testing Reactor (JMTR) is a light water moderated and cooled tank-type reactor, and its thermal power is 50 MW. The JMTR is categorized as high flux testing reactors in the world. The JMTR has been utilized for irradiation experiments of nuclear fuels and materials, as well as for radioisotope productions since the first criticality in March 1968 until August 2006. JAEA is decided to refurbish the JMTR as an important fundamental infrastructure to promote the nuclear research and development. And The JMTR refurbishment work is carried out for 4 years from 2007. Before refurbishment work, from August 2006 to March 2007, all concerned renewal facilities were selected from evaluation on their damage and wear in terms of aging. Facilities which replacement parts are no longer manufactured or not likely to be manufactured continuously in near future, are selected as renewal ones. Replace priority was decided with special attention to safety concerns. A monitoring of aging condition by the regular maintenance activity is an important factor in selection of continuous using after the restart. In this report, renewal of the cooling system within refurbishment facilities in the JMTR is summarized. (author)

Evaluation of Radiological Impacts on the Operating Kartini Reactor and Natural Radioactivity of the Site Plan of Nuclear Power Plant Area

International Nuclear Information System (INIS)

Yazid, M; Sutresna, G; Sulistyono, A; Ngasifudin

1996-01-01

This radiological impacts evaluation covered of radioactivity in water, soil, grass, air samples and ambient gamma radiation that have been carried out in the Kartini reactor area and in the site plan of nuclear power plan are at Ujung Lemah Abang, Jepara, Central Java. The aim of this research was to determine that radiological impacts in the environment around the Kartini reactor compared to natural radioactivity for site plan of nuclear power plan area. The radioactivity in the water, soil and grass samples ware measured by low background beta counting system and were identified by low background gamma spectrometer. The radioactivity in the air samples was measured by beta portable counting system and the ambient gamma radiation was measured by portable high pressurized ionization chamber model RSS-112 Reuther-Stokes. The reactor data measurement was compared to the site plan of nuclear power plant area data for evaluation of radiological impacts on the operating reactor. From the evaluation and comparison can be concluded there are no indication of the radionuclide release from the reactor operation. The average radiactivity in the water, soil grass and air sample from the reactor area were between 0.17 - 0.61 Bq/1; 0,47 - 0,74 Bq/g; 4.43 - 4.60 Bq/g.ash and 49.53 - 70.90 x 10 Bq/cc. The average radioactivity of those sample from the nuclear power plant area were between 0.06-0.90 Bq/I; 0.02-0.86 Bq/g; 1.68-8.07 Bq/g.ash and 65.0-152.3 x 10 Bq/cc. The ambient gamma radiation were between 6.9-36.7 urad/h for the reactor area and 6.8-19.2 urad/h for the nuclear power plant area

Dynamic analysis of the PEC fast reactor vessel: On-site tests and mathematical models

International Nuclear Information System (INIS)

Zola, M.; Martelli, A.; Masoni, P.; Scandola, G.

1988-01-01

This paper presents the main features and results of the on-site dynamic tests and the related numerical analyses carried out for the PEC reactor vessel. The purpose is to provide an example of on-site testing of large components, stressing the problems encountered during the experiments, as well as in the processing phase of the test results and for the comparisons between calculations and measurements. Tests, performed by ISMES on behalf of ENEA, allowed the dynamic response of the empty vessel to be measured, thus providing data for the verification of the numerical models of the vessel supporting structure adopted in the PEC reactor-block seismic analysis. An axisymmetric model of the vessel, implemented in the NOVAX code, had been developed in the framework of the detailed numerical studies performed by NOVATOME (again on behalf of ENEA), to check the beam schematization with fluid added mass model adopted by ANSALDO in SAP-IV and ANSYS for the reactor-block design calculations. Furthermore, a numerical model, describing vessel supporting structure in detail, was also developed by ANSALDO and implemented in the SAP-IV code. The test conditions were analysed by use of these and the design models. Comparisons between calculations and measurements showed particularly good agreement with regard to first natural frequency of the vessel and rocking stiffness of the vessel supporting structure, i.e. those parameters on which vessel seismic amplification mainly depends: this demonstrated the adequacy of the design analysis to correctly calculate the seismic motion at the PEC core diagrid. (author). 5 refs, 23 figs, 4 tabs

Dynamic analysis of the PEC fast reactor vessel: on-site tests and mathematical models

International Nuclear Information System (INIS)

Zola, Maurizio; Martelli, Alessandro; Maresca, Giuseppe; Masoni, Paolo; Scandola, Giani; Descleves, Pierre

1988-01-01

This paper presents the main features and results of the on-site dynamic tests and the related numerical analysis carried out for the PEC reactor vessel. The purpose is to provide an example of on-site testing of large components, stressing the problems encountered during the experiments, as well as in the processing phase of the test results and for the comparisons between calculations and measurements. Tests, performed by ISMES on behalf of ENEA, allowed the dynamic response of the empty vessel to be measured, thus providing data for the verification of the numerical models of the vessel supporting structure adopted in the PEC reactor-block seismic analysis. An axisymmetric model of the vessel, implemented in the vessel, implemented in the NOVAK code, had been developed in the framework of the detailed numerical studies performed by NOVATOME (again on behalf of ENEA), to check the beam schematization with fluid added mass model adopted by ANSALDO in SAP-IV and ANSYS for the reactor-block design calculations. Furthermore, a numerical model, describing vessel supporting structure in detail, was also developed by ANSALDO and implemented in the SAP-IV code. The test conditions were analysed by use of these and the design models. Comparisons between calculations and measurements showed particularly good agreement with regard to first natural frequency of the vessel and rocking stiffness of the vessel supporting structure, i.e. those parameters on which vessel seismic amplification mainly depends: this demonstrated the adequacy of the design analysis to correctly calculate the seismic motion at the PEC core diagrid. (author)

Soil class around me Serpong experimental power reactor (EPR) site plan base on micro tremor data

International Nuclear Information System (INIS)

Marjiyono; Soehaimi A; Hadi Suntoko; Yuliastuti; Syaeful H

2015-01-01

Surface geological characteristics has an important role on site response analysis in a region. In regard with experimental power reactor (EPR) construction plan in Serpong, the subsurface modeling from combination array and single station micro tremor data was done. The array and single station micro tremor measurement were performed in 9 and 90 sites, respectively, at ± 1 km radius around the EPR site plan. The Vs30 value was calculated from shear wave velocity structure around the investigated area. The soil classification based on Vs30 in the investigated area generally consists of SD (medium soil) and SC (soft rock) class. The EPR site plan its self in the SD class region. (author)

Savannah River Site production reactor safety analysis report

International Nuclear Information System (INIS)

1996-01-01

The process water system (PWS) is designed to remove heat produced in the reactor from the fission process, gamma radiation absorption, and fission product decay. Heat removal is accomplished by circulating heavy water through the reactor. Cooling is provided for fuel assemblies, target assemblies, control rods, bulk moderator, deflector plate, reactor tank, and reactor structural components. Approximately 90% of the heat load is generated in the fuel and target assemblies, 5% in the moderator, and 5% in the shielding. In addition to serving as the-heat transfer medium, the process water moderates neutrons produced by fission in the fuel. D 2 O is used in this application because of its favorable moderating and neutron capture properties, which result in high neutron efficiency and reactor productivity. The PWS piping and components also provide a high-integrity leak barrier against loss of moderator and the radioactive fission and corrosion products. Components of the PWS are located in the reactor building between the -40-foot elevation and the 0-foot elevation. Specific locations include the process room, heat exchanger bay, motor rooms, and pump rooms. The system diagram is shown in Figure 5.1-2. PWS design data are presented in Table 5.1-1. The PWS consists of six parallel heat transfer loops. In each loop, approximately 25,000 gpm of D 2 O is circulated from one of six outlet nozzles in the bottom of the reactor tank through a motor-operated valve (MOV) to the suction side of the process water pump. Each pump is driven by an AC motor and a DC motor through a gear reducer unit. A 3-ton flywheel on the drive shaft of the AC motor provides gradual flow coastdown when power is lost. During reactor operation, the DC motors are operated continuously from the diesel generator sets as backup to the AC motors. Following shutdown, the DC motors are operated to provide adequate circulation and core cooling

Evaluation of Fe(II) oxidation at an acid mine drainage site using laboratory-scale reactors

Science.gov (United States)

Brown, Juliana; Burgos, William

2010-05-01

Acid mine drainage (AMD) is a severe environmental threat to the Appalachian region of the Eastern United States. The Susquehanna and Potomac River basins of Pennsylvania drain to the Chesapeake Bay, which is heavily polluted by acidity and metals from AMD. This study attempted to unravel the complex relationships between AMD geochemistry, microbial communities, hydrodynamic conditions, and the mineral precipitates for low-pH Fe mounds formed downstream of deep mine discharges, such as Lower Red Eyes in Somerset County, PA, USA. This site is contaminated with high concentrations of Fe (550 mg/L), Mn (115 mg/L), and other trace metals. At the site 95% of dissolved Fe(II) and 56% of total dissolved Fe is removed without treatment, across the mound, but there is no change in the concentration of trace metals. Fe(III) oxides were collected across the Red Eyes Fe mound and precipitates were analyzed by X-ray diffraction, electron microscopy and elemental analysis. Schwertmannite was the dominant mineral phase with traces of goethite. The precipitates also contained minor amounts of Al2O3, MgO,and P2O5. Laboratory flow-through reactors were constructed to quantify Fe(II) oxidation and Fe removal over time at terrace and pool depositional facies. Conditions such as residence time, number of reactors in sequence and water column height were varied to determine optimal conditions for Fe removal. Reactors with sediments collected from an upstream terrace oxidized more than 50% of dissolved Fe(II) at a ten hour residence time, while upstream pool sediments only oxidized 40% of dissolved Fe(II). Downstream terrace and pool sediments were only capable of oxidizing 25% and 20% of Fe(II), respectively. Fe(II) oxidation rates measured in the reactors were determined to be between 3.99 x 10-8and 1.94 x 10-7mol L-1s-1. The sediments were not as efficient for total dissolved Fe removal and only 25% was removed under optimal conditions. The removal efficiency for all sediments

Study plan for conducting a section 316(a) demonstration: K-Reactor cooling tower, Savannah River Site

International Nuclear Information System (INIS)

Paller, M.H.

1991-02-01

The K Reactor at the Savannah River Site (SRS) began operation in 1954. The K-Reactor pumped secondary cooling water from the Savannah River and discharged directly to the Indian Grave Branch, a tributary of Pen Branch which flows to the Savannah River. During earlier operations, the temperature and discharge rates of cooling water from the K-reactor were up to approximately 70 degree C and 400 cfs, substantially altering the thermal and flow regimes of this stream. These discharges resulted in adverse impacts to the receiving stream and wetlands along the receiving stream. As a component of a Consent Order (84-4-W as amended) with the South Carolina Department of Health and Environmental Control, the Department of Energy (DOE) evaluated the alternatives for cooling thermal effluents from K Reactor and concluded that a natural draft recirculating cooling tower should be constructed. The cooling tower will mitigate thermal and flow factors that resulted in the previous impacts to the Indian Grave/Pen Branch ecosystem. The purpose of the proposed biological monitoring program is to provide information that will support a Section 316(a) Demonstration for Indian Grave Branch and Pen Branch when K-Reactor is operated with the recirculating cooling tower. The data will be used to determine that Indian Grave Branch and Pen Branch support Balanced Indigenous Communities when K-Reactor is operated with a recirculating cooling tower. 4 refs., 1 fig. 1 tab

Design guide for category II reactors light and heavy water cooled reactors

International Nuclear Information System (INIS)

Brynda, W.J.; Lobner, P.R.; Powell, R.W.; Straker, E.A.

1978-05-01

The Department of Energy (DOE), in the ERDA Manual, requires that all DOE-owned reactors be sited, designed, constructed, modified, operated, maintained, and decommissioned in a manner that gives adequate consideration to health and safety factors. Specific guidance pertinent to the safety of DOE-owned reactors is found in Chapter 0540 of the ERDA Manual. The purpose of this Design Guide is to provide additional guidance to aid the DOE facility contractor in meeting the requirement that the siting, design, construction, modification operation, maintainance, and decommissioning of DOW-owned reactors be in accordance with generally uniform standards, guide and codes which are comparable to those applied to similar reactors licensed by the Nuclear Regulatory Commission (NRC). This Design Guide deals principally with the design and functional requirements of Category II reactor structure, components, and systems

Studies on decommissioning of TRIGA reactors and site restoration technologies in the Republic of Korea

International Nuclear Information System (INIS)

Oh, Won-Zin; Kim, Gye-Nam; Won, Hui-Jun

2002-01-01

Research and development on research reactor decommissioning and environmental restoration has been carried out at KAERI since 1997 to prepare for the decommissioning of KAERI's two TRIGA-type research reactors, which had been shut down since 1995. A 3-D graphic model of the TRIGA research reactor was built using IGRIP. The dismantling process was simulated in the graphic environment to verify the feasibility of individual operations before the execution of the remote dismantling process. An under-water wall-climbing robot, moving by propeller injection, and identifying its coordinates by using a laser sensor, was developed and tested in the TRIGA reactor pool by measuring a radioactive contamination map of the reactor surface. Using MODFLOW and TRIGA site geological data, a computer simulation of the underground migration of residual radionuclides, after the TRIGA reactor decommissioning, was carried out. It was found that the underground migration rate was very slow such that, when radionuclide decay and dilution are considered, the residual radionuclides will not have a significant environmental impact. The soil decontamination R and D, using soil washing, solvent flushing and electro-decontamination technologies, was carried out to determine the best method for decontaminating the soil waste accumulated in KAERI. The decontamination results indicated that, using the soil washing method, more than 80% of the soil wastes could be decontaminated well enough to discharge them to the environment. It was also determined that the control of solution pH and temperature in the soil washing process is important for the reduction of decontamination waste. Further decontamination, using an electro-kinetic decontamination method, was considered necessary for the residual soil waste, which consisted mainly of fine soil particles. (author)

Analysis of Removal Alternatives for the Heavy Water Components Test Reactor at the Savannah River Site

International Nuclear Information System (INIS)

Owen, M.B.

1996-08-01

This engineering study was developed to evaluate different options for decommissioning of the Heavy Water Components Test Reactor (HWCTR) at the Savannah River Site. This document will be placed in the DOE-SRS Area reading rooms for a period of 30 days in order to obtain public input to plans for the demolition of HWCTR

Geotechnical investigation for seismic issues for K-reactor area at Savannah River Site

International Nuclear Information System (INIS)

Castro, G.; Reeves, C.Q.

1991-01-01

A geotechnical investigation has been completed at Savannah River Site to characterize the foundation conditions in K-Reactor Area and confirm soil design properties for use in seismic qualification of structures. The scope of field work included ten soil borings to a 200-foot depth with split-spoon and undisturbed sampling. Additionally, 42 cone penetrometer tests were performed with seismic down-hole measurements. Three cross-hole shear wave velocity tests were also completed to confirm the assumed dynamic properties which had been used in preliminary seismic analysis

Review of reports associated with systems of the K, P and L reactors at the Savannah River Site

International Nuclear Information System (INIS)

Cowgill, M.G.

1992-02-01

Six reports associated with the structural integrity of several systems of the Savannah River Site reactors are reviewed. The focus is on the materials-related aspects of the reports and no attempt is made to address the stress analysis-related issues

Rock siting of nuclear power plants from a reactor safety standpoint. Status report October 1974

International Nuclear Information System (INIS)

1975-01-01

The aim of this study is to clearify the advantages and disadvantages of an underground nuclear power plant from a reactor safety point of view, compared to a plant above ground. Principles for the technical design of a rock sited BWR nuclear power plant is presented. Also questions of sabotage and closing down the plant at the end of the operational period are treated. (K.K.)

MANHATTAN PROJECT B REACTOR HANFORD WASHINGTON [HANFORD'S HISTORIC B REACTOR (12-PAGE BOOKLET)

Energy Technology Data Exchange (ETDEWEB)

GERBER MS

2009-04-28

The Hanford Site began as part of the United States Manhattan Project to research, test and build atomic weapons during World War II. The original 670-square mile Hanford Site, then known as the Hanford Engineer Works, was the last of three top-secret sites constructed in order to produce enriched uranium and plutonium for the world's first nuclear weapons. B Reactor, located about 45 miles northwest of Richland, Washington, is the world's first full-scale nuclear reactor. Not only was B Reactor a first-of-a-kind engineering structure, it was built and fully functional in just 11 months. Eventually, the shoreline of the Columbia River in southeastern Washington State held nine nuclear reactors at the height of Hanford's nuclear defense production during the Cold War era. The B Reactor was shut down in 1968. During the 1980's, the U.S. Department of Energy began removing B Reactor's support facilities. The reactor building, the river pumphouse and the reactor stack are the only facilities that remain. Today, the U.S. Department of Energy (DOE) Richland Operations Office offers escorted public access to B Reactor along a designated tour route. The National Park Service (NPS) is studying preservation and interpretation options for sites associated with the Manhattan Project. A draft is expected in summer 2009. A final report will recommend whether the B Reactor, along with other Manhattan Project facilities, should be preserved, and if so, what roles the DOE, the NPS and community partners will play in preservation and public education. In August 2008, the DOE announced plans to open B Reactor for additional public tours. Potential hazards still exist within the building. However, the approved tour route is safe for visitors and workers. DOE may open additional areas once it can assure public safety by mitigating hazards.

Department of Energy's High Flux Beam Reactor (HFBR), September 15--19, 1980: An independent on-site safety review

International Nuclear Information System (INIS)

1981-02-01

The intent of this on-site safety review was to make a broad management assessment of HFBR operations, rather than conduct a detailed in-depth audit. The result of the review should only be considered as having identified trends or indications. The Team's observations and recommendations for the most part are based upon licensed reactor facility practices used to meet industry standards. These standards form the basis for many of the comments in this report. The Team believes that a uniform minimum standard of performance should be achieved in the operation of DOE reactors. In order to assure that this is accomplished, clear standards are necessary. Consistent with the past AEC and ERDA policy, the team has used the standards of the commercial nuclear power industry. It is recognized that this approach is conservative in that the HFBR reactor has a significantly greater degree of inherent safety (low pressure, temperature, power, etc.) than a licensed reactor

Risk-oriented analysis of the German prototype fast breeder reactor SNR-300: off-site accident consequence model and results of the study

International Nuclear Information System (INIS)

Bayer, A.; Ehrhardt, J.

1984-01-01

Accident off-site consequence calculations and risk assessments performed for the ''risk oriented analysis'' of the German prototype fast breeder reactor SNR-300 were performed with a modified version of the off-site accident consequence model UFOMOD. The modifications mainly relate to the deposition and resuspension processes, the ingestion model, and the dose factors. Consequence calculations at the site of Kalkar on the Rhine River were performed for 115 weather sequences in 36 wind directions. They were based on seven release categories evaluated for the SNR-300 with two different fueling strategies: plutonium from Magnox reactors only and plutonium from light water reactors and Magnox reactors. In parallel, the corresponding frequencies of occurrence are determined. The following results are generated: 1. complementary cumulative frequency distribution functions for collective fatalities and collective doses 2. expected values of the collective fatalities and collective doses as well as distance-dependent expected values of individual fatality 3. contributions of the different exposure pathways to fatalities with respect to the various organs. For comparison with the risk of a PWR-1300, calculations for the PWR-1300 of the ''German Risk Study'' were repeated with the same modified consequence model. Comparison shows that smaller risks result for the SNR-300. However, the confidence interval bandwidths obtained for the frequencies of the release categories for the SNR-300 are larger than those of the PWR-1300

Seismic qualification of safety class components in non-reactor nuclear facilities at Hanford site

International Nuclear Information System (INIS)

Ocoma, E.C.

1989-01-01

This paper presents the methods used during the walkdowns to compile as-built structural information to seismically qualify or verify the seismic adequacy of safety class components in the Plutonium Finishing Plant complex. The Plutonium finishing Plant is a non-reactor nuclear facility built during the 1950's and was designed to the Uniform Building Code criteria for both seismic and wind events. This facility is located at the US Department of Energy Hanford Site near Richland, Washington

Analysis of removal alternatives for the Heavy Water Components Test Reactor at the Savannah River Site. Revision 1

Energy Technology Data Exchange (ETDEWEB)

Owen, M.B.

1997-04-01

This engineering study evaluates different alternatives for decontamination and decommissioning of the Heavy Water Components Test Reactor (HWCTR). Cooled and moderated with pressurized heavy water, this uranium-fueled nuclear reactor was designed to test fuel assemblies for heavy water power reactors. It was operated for this purpose from march of 1962 until December of 1964. Four alternatives studied in detail include: (1) dismantlement, in which all radioactive and hazardous contaminants would be removed, the containment dome dismantled and the property restored to a condition similar to its original preconstruction state; (2) partial dismantlement and interim safe storage, where radioactive equipment except for the reactor vessel and steam generators would be removed, along with hazardous materials, and the building sealed with remote monitoring equipment in place to permit limited inspections at five-year intervals; (3) conversion for beneficial reuse, in which most radioactive equipment and hazardous materials would be removed and the containment building converted to another use such as a storage facility for radioactive materials, and (4) entombment, which involves removing hazardous materials, filling the below-ground structure with concrete, removing the containment dome and pouring a concrete cap on the tomb. Also considered was safe storage, but this approach, which has, in effect, been followed for the past 30 years, did not warrant detailed evaluation. The four other alternatives were evaluate, taking into account factors such as potential effects on the environment, risks, effectiveness, ease of implementation and cost. The preferred alternative was determined to be dismantlement. This approach is recommended because it ranks highest in the comparative analysis, would serve as the best prototype for the site reactor decommissioning program and would be most compatible with site property reuse plans for the future.

Analysis of removal alternatives for the Heavy Water Components Test Reactor at the Savannah River Site. Revision 1

International Nuclear Information System (INIS)

Owen, M.B.

1997-04-01

This engineering study evaluates different alternatives for decontamination and decommissioning of the Heavy Water Components Test Reactor (HWCTR). Cooled and moderated with pressurized heavy water, this uranium-fueled nuclear reactor was designed to test fuel assemblies for heavy water power reactors. It was operated for this purpose from march of 1962 until December of 1964. Four alternatives studied in detail include: (1) dismantlement, in which all radioactive and hazardous contaminants would be removed, the containment dome dismantled and the property restored to a condition similar to its original preconstruction state; (2) partial dismantlement and interim safe storage, where radioactive equipment except for the reactor vessel and steam generators would be removed, along with hazardous materials, and the building sealed with remote monitoring equipment in place to permit limited inspections at five-year intervals; (3) conversion for beneficial reuse, in which most radioactive equipment and hazardous materials would be removed and the containment building converted to another use such as a storage facility for radioactive materials, and (4) entombment, which involves removing hazardous materials, filling the below-ground structure with concrete, removing the containment dome and pouring a concrete cap on the tomb. Also considered was safe storage, but this approach, which has, in effect, been followed for the past 30 years, did not warrant detailed evaluation. The four other alternatives were evaluate, taking into account factors such as potential effects on the environment, risks, effectiveness, ease of implementation and cost. The preferred alternative was determined to be dismantlement. This approach is recommended because it ranks highest in the comparative analysis, would serve as the best prototype for the site reactor decommissioning program and would be most compatible with site property reuse plans for the future

Design of a permanent Cd-shielded epithermal neutron irradiation site in the Syrian Miniature Neutron Source Reactor

International Nuclear Information System (INIS)

Khattab, K.; Haddad, Kh.; Haj-Hassan, H.

2008-01-01

A Cd-shield (cylindrical shell 1 mm in thickness, 34 mm in diameter and 180 mm in length) was used to design a permanent epithermal neutron irradiation site for epithermal neutron activation analysis (ENAA) in the Syrian Miniature Neutron Source Reactor (MNSR). This site was achieved by shielding the surface of the aluminum tube of one of the outer irradiation sites. The calculated depression ratio of thermal neutron flux was 1/10. Homogeneity of the neutron flux in the first outer irradiation site has been found numerically using the WIMSD4 and CITATION codes and experimentally by irradiating five short copper wires using the outer irradiation capsule. Good agreement was obtained between the calculated and the measured results of the neutron flux distributions. (author)

Design of a permanent Cd-shielded epithermal neutron irradiation site in the Syrian Miniature Neutron Source Reactor

International Nuclear Information System (INIS)

Khattab, K.; Haddad, Kh.; Haj-Hassan, H.

2009-01-01

A Cd-shield (cylindrical shell 1 mm in thickness, 34 mm in diameter and 180 mm in length) was used to design a permanent epithermal neutron irradiation site for epithermal neutron activation analysis (ENAA) in the Syrian Miniature Neutron Source Reactor (MNSR). This site was achieved by shielding the surface of the aluminum tube of one of the outer irradiation sites. The calculated depression ratio of thermal neutron flux was 1/10. Homogeneity of the neutron flux in the first outer irradiation site has been found numerically using the WIMSD4 and CITATION codes and experimentally by irradiating five short copper wires using the outer irradiation capsule. Good agreement was obtained between the calculated and the measured results of the neutron flux distributions. (author)

Nuclear reactors. Introduction

International Nuclear Information System (INIS)

Boiron, P.

1997-01-01

This paper is an introduction to the 'nuclear reactors' volume of the Engineers Techniques collection. It gives a general presentation of the different articles of the volume which deal with: the physical basis (neutron physics and ionizing radiations-matter interactions, neutron moderation and diffusion), the basic concepts and functioning of nuclear reactors (possible fuel-moderator-coolant-structure combinations, research and materials testing reactors, reactors theory and neutron characteristics, neutron calculations for reactor cores, thermo-hydraulics, fluid-structure interactions and thermomechanical behaviour of fuels in PWRs and fast breeder reactors, thermal and mechanical effects on reactors structure), the industrial reactors (light water, pressurized water, boiling water, graphite moderated, fast breeder, high temperature and heavy water reactors), and the technology of PWRs (conceiving and building rules, nuclear parks and safety, reactor components and site selection). (J.S.)

Safety assessment of Department of Energy nuclear reactors

International Nuclear Information System (INIS)

1981-03-01

One of the first tasks of the NFPQT Committee was to determine which DOE reactors would be assessed. The Committee determined that in view of the limited time available to conduct the assessment, 13 DOE reactors were of such size (physical, power or fission product inventory) to warrant review. This determination was approved by the Under Secretary. A decision was also made in the cases of three weapons material production reactors, C, K and P, to concentrate on the K reactor only, since all three are of the same basic design, have the same operating features, are all at the same site, and are all operated by the same contractor. The assessment was accomplished in the following ways: reviewing the results of assessments conducted by the DOE organizations with reactor safety responsibilities, which were undertaken in compliance with the request of the various program directors; reviewing selected documents that were requested by the Committee and assembled at DOE Headquarters; interviewing DOE Headquarters and Field Office personnel; and conducting on-site reviews of four reactors located at four different sites. The four reactors for on-site reviews were: Advanced Test Reactor (ATR); K Production Reactor; High Flux Beam Reactor (HFBR); and High Flux Isotope Reactor (HFIR). Specific findings and recommendations from the assessment are presented

Present status of research reactor decommissioning programme in Indonesia

International Nuclear Information System (INIS)

Suripto, A.; Mulyanto, N.

2002-01-01

At present Indonesia has 3 research reactors, namely the 30 MW MTR-type multipurpose reactor at Serpong Site, two TRIGA-type research reactors, the first one being 1 MW located at Bandung Site and the second one a small reactor of 100 kW at Yogyakarta Site. The TRIGA Reactor at the Bandung Site reached its first criticality at 250 kW in 1964, and then was operated at 1000 kW since 1971. In October 2000 the reactor power was successfully upgraded to 2 MW. This reactor has already been operated for 38 years. There is not yet any decision for the decommissioning of this reactor. However it will surely be an object for the near future decommissioning programme and hence anticipation for the above situation becomes necessary. The regulation on decommissioning of research reactor is already issued by the independent regulatory body (BAPETEN) according to which the decommissioning permit has to be applied by the BATAN. For Indonesia, an early decommissioning strategy for research reactor dictates a restricted re-use of the site for other nuclear installation. This is based on high land price, limited availability of radwaste repository site, and other cost analysis. Spent graphite reflector from the Bandung TRIGA reactor is recommended for a direct disposal after conditioning, without any volume reduction treatment. Development of human resources, technological capability as well as information flow from and exchange with advanced countries are important factors for the future development of research reactor decommissioning programme in Indonesia. (author)

Assessment of Westinghouse Hanford Company methods for estimating radionuclide release from ground disposal of waste water at the N Reactor sites

International Nuclear Information System (INIS)

1988-09-01

This report summarizes the results of an independent assessment by Golder Associates, Inc. of the methods used by Westinghouse Hanford Company (Westinghouse Hanford) and its predecessors to estimate the annual offsite release of radionuclides from ground disposal of cooling and other process waters from the N Reactor at the Hanford Site. This assessment was performed by evaluating the present and past disposal practices and radionuclide migration data within the context of the hydrology, geology, and physical layout of the N Reactor disposal site. The conclusions and recommendations are based upon the available data and simple analytical calculations. Recommendations are provided for conducting more refined analyses and for continued field data collection in support of estimating annual offsite releases. Recommendations are also provided for simple operational and structural measures that should reduce the quantities of radionuclides leaving the site. 5 refs., 9 figs., 1 tab

International ENEA/ISMES/ENS specialist meeting on 'On-site experimental verification of the seismic behaviour of nuclear reactor structures and components'. Proceedings

International Nuclear Information System (INIS)

1988-01-01

The seismic verification of nuclear plants is a subject of increasing interest in all the industrial countries, with respect to both the safety aspects and the impact of the seismic event on the design and the costs of a nuclear reactor. This topic is especially of great interest for a country like Italy, whose territory is unfortunately characterized by non - negligible seismicity: we remember, not too many years ago, the catastrophic earthquakes of Frioul and Irpinia, that caused thousands of dead people. The meeting aimed at establishing the state-of-the-art on on-site testing of nuclear reactors structures and components, with particular attention to experiences and research programmes concerning: methodologies of on-site tests and interpretation of the experimental data; seismic monitoring systems, recorded data, their use and interpretation; calibration and validation of numerical analyses. Six technical sessions were held, during which 23 high papers were presented and discussed, and six panel discussions were held (the importance of discussion was emphasized in the meeting). The technical contributions consisted of: an introduction paper, summarizing the seismic studies performed in Italy for PEC reactor and explaining the reasons why on-site tests had been performed on this reactor; 6 invited lectures, one for each of the countries that are more deeply involved in seismic analysis, providing the state-of-the-art on the topics of interest for the meeting; 16 contributed papers dealing with more specific technical items, related to the various countries and international organizations

International ENEA/ISMES/ENS specialist meeting on 'On-site experimental verification of the seismic behaviour of nuclear reactor structures and components'. Proceedings

Energy Technology Data Exchange (ETDEWEB)

NONE

1988-07-01

The seismic verification of nuclear plants is a subject of increasing interest in all the industrial countries, with respect to both the safety aspects and the impact of the seismic event on the design and the costs of a nuclear reactor. This topic is especially of great interest for a country like Italy, whose territory is unfortunately characterized by non - negligible seismicity: we remember, not too many years ago, the catastrophic earthquakes of Frioul and Irpinia, that caused thousands of dead people. The meeting aimed at establishing the state-of-the-art on on-site testing of nuclear reactors structures and components, with particular attention to experiences and research programmes concerning: methodologies of on-site tests and interpretation of the experimental data; seismic monitoring systems, recorded data, their use and interpretation; calibration and validation of numerical analyses. Six technical sessions were held, during which 23 high papers were presented and discussed, and six panel discussions were held (the importance of discussion was emphasized in the meeting). The technical contributions consisted of: an introduction paper, summarizing the seismic studies performed in Italy for PEC reactor and explaining the reasons why on-site tests had been performed on this reactor; 6 invited lectures, one for each of the countries that are more deeply involved in seismic analysis, providing the state-of-the-art on the topics of interest for the meeting; 16 contributed papers dealing with more specific technical items, related to the various countries and international organizations.

Gas-cooled reactor technology safety and siting. Report of a technical committee meeting. Working material

Energy Technology Data Exchange (ETDEWEB)

NONE

1990-07-01

At the invitation of the Government of the Union of Soviet Socialist Republics, the Eleventh International Conference on the HTGR and the IAEA Technical Committee Meeting on Gas-Cooled Reactor Technology, Safety and Siting were held in Dimitrovgrad, USSR, on June 21-23, 1989. The Technical Committee Meeting provided the Soviet delegates with an opportunity to display the breadth of their program on HTGRs to an international audience. Nearly one-half of the papers were presented by Soviet participants. Among the highlights of the meeting were the following: the diverse nature and large magnitude of the Soviet research and development program on high temperature gas-cooled reactors; the Government approval of the budget for the construction of the 30 MWt High Temperature Test Reactor (HTTR) in Japan (The schedule contemplates a start of construction in spring 1990 on a site at the Oarai Research Establishment and about a five year construction period.); disappointment in the announced plans to shutdown both the Fort St. Vrain (FSV) plant in the United States (US) and the Thorium High Temperature Reactor (THTR-300) in Germany (These two reactors presently represent the only operating HTGRs in the world since the AVR plant in Juelich, Germany, was also shutdown at the end of 1988.); the continuing negotiations between Germany and the USSR on the terms of the co-operation between the two countries for the construction of a HTR Module supplemented by joint research and development activities aimed at increasing coolant outlet temperatures from 750 deg. C to 950 deg. C; the continued enthusiasm displayed by both the US and German representatives for the potential of the small modular designs under development in both countries and the ability for these designs to meet the stringent requirements demanded for the future expansion of nuclear power; the combining of the HTGR technology interest of ABB-Atom and Siemens in Germany into a joint enterprise, HTR GmbH, in May 1989

Gas-cooled reactor technology safety and siting. Report of a technical committee meeting. Working material

International Nuclear Information System (INIS)

1990-01-01

At the invitation of the Government of the Union of Soviet Socialist Republics, the Eleventh International Conference on the HTGR and the IAEA Technical Committee Meeting on Gas-Cooled Reactor Technology, Safety and Siting were held in Dimitrovgrad, USSR, on June 21-23, 1989. The Technical Committee Meeting provided the Soviet delegates with an opportunity to display the breadth of their program on HTGRs to an international audience. Nearly one-half of the papers were presented by Soviet participants. Among the highlights of the meeting were the following: the diverse nature and large magnitude of the Soviet research and development program on high temperature gas-cooled reactors; the Government approval of the budget for the construction of the 30 MWt High Temperature Test Reactor (HTTR) in Japan (The schedule contemplates a start of construction in spring 1990 on a site at the Oarai Research Establishment and about a five year construction period.); disappointment in the announced plans to shutdown both the Fort St. Vrain (FSV) plant in the United States (US) and the Thorium High Temperature Reactor (THTR-300) in Germany (These two reactors presently represent the only operating HTGRs in the world since the AVR plant in Juelich, Germany, was also shutdown at the end of 1988.); the continuing negotiations between Germany and the USSR on the terms of the co-operation between the two countries for the construction of a HTR Module supplemented by joint research and development activities aimed at increasing coolant outlet temperatures from 750 deg. C to 950 deg. C; the continued enthusiasm displayed by both the US and German representatives for the potential of the small modular designs under development in both countries and the ability for these designs to meet the stringent requirements demanded for the future expansion of nuclear power; the combining of the HTGR technology interest of ABB-Atom and Siemens in Germany into a joint enterprise, HTR GmbH, in May 1989

History of the 185-/189-D thermal hydraulics laboratory and its effects on reactor operations at the Hanford Site

International Nuclear Information System (INIS)

Gerber, M.S.

1994-09-01

The 185-D deaeration building and the 189-D refrigeration building were constructed at Hanford during 1943 and 1944. Both buildings were constructed as part of the influent water cooling system for D reactor. The CMS studies eliminated the need for 185-D function. Early gains in knowledge ended the original function of the 189-D building mission. In 1951, 185-D and 189-D were converted to a thermal-hydraulic laboratory. The experiments held in the thermal-hydraulic lab lead to historic changes in Hanford reactor operations. In late 1951, the exponential physics experiments were moved to the 189-D building. In 1958, new production reactor experiments were begun in 185/189-D. In 1959, Plutonium Recycle Test Reactor experiments were added to the 185/189-D facility. By 1960, the 185/189-D thermal hydraulics laboratory was one of the few full service facilities of its type in the nation. During the years 1961--1963 tests continued in the facility in support of existing reactors, new production reactors, and the Plutonium Recycle Test Reactor. In 1969, Fast Flux Test Facility developmental testings began in the facility. Simulations in 185/189-D building aided in the N Reactor repairs in the 1980's. In 1994 the facility was nominated to the National Register of Historic Places, because of its pioneering role over many years in thermal hydraulics, flow studies, heat transfer, and other reactor coolant support work. During 1994 and 1995 it was demolished in the largest decontamination and decommissioning project thus far in Hanford Site history

Nuclear reactors sited deep underground in steel containment vessels

Energy Technology Data Exchange (ETDEWEB)

Bourque, Robert [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States)

2006-07-01

Although nuclear power plants are certainly very safe, they are not perceived as safe by the general populace. Also, there are concerns about overland transport of spent fuel rods and other irradiated components. It is hereby proposed that the nuclear components of nuclear power plants be placed in deep underground steel vessels with secondary coolant fed from them to turbines at or near the surface. All irradiated components, including spent fuel, would remain in the chamber indefinitely. This general concept was suggested by the late Edward Teller, generated some activity 20-25 years ago and appears to be recently reviving in interest. Previous work dealt with issues of geologic stability of underground, possibly reinforced, caverns. This paper presents another approach that makes siting independent of geology by placing the reactor components in a robust steel vessel capable of resisting full overburden pressure as well as pressures resulting from accident scenarios. Structural analysis of the two vessel concepts and approximate estimated costs are presented. This work clears the way for the extensive discussions required to evaluate the advantages of this concept. (author)

Siting of nuclear power plants in densely populated countries

International Nuclear Information System (INIS)

Togo, Y.

1981-01-01

In evaluating the safety of reactor siting, three typical approaches can be applied; the deterministic approach, the probabilistic approach and the combined approach. In regard to a risk associated with siting, the design of a reactor has to do with both individual and societal risk, while exclusion distance mainly has to do with individual risk, and surrounding population primarily has to do with societal risk. Consequently, in a densely populated area, more attention should be paid to societal risk. There are many reactor sites in the world which can be described as concentrated siting. Although concentrated siting has a lot of merits, such as reducing the construction cost or maintenance cost of reactors, more careful consideration should be paid to safety-related matters of such concentrated reactors because the risk to the individual from accidents caused by concentrated reactors is larger than that from a single reactor. As for the recent controversial issue concerning siting criteria, it appears that the present international consensus on siting philosophy is still valid after the TMI accident. (author)

Remediation of Site of Decommissioning Research Reactor

Energy Technology Data Exchange (ETDEWEB)

Danilovich, A.S.; Ivanov, O.P.; Lemus, A.V.; Pavlenko, V.I.; Potapov, V.N.; Semenov, S.G.; Shisha, A.D.; Chesnokov, A.V. [National Research Center ' Kurchatov Institute' , 123182, Moscow (Russian Federation)

2014-07-01

In the world the most widespread method of soil decontamination consists of removing the contaminated upper layer and sending it for long-term controlled storage. However, implementation of this soil cleanup method for remediation of large contaminated areas would involve high material and financial expenditures, because it produces large amounts of radioactive waste demanding removal to special storage sites. Contaminated soil extraction and cleanup performed right on the spot of remediation activities represents a more advanced and economically acceptable method. Radiological separation of the radioactive soil allows reducing of amount of radwaste. Studies performed during the liquidation of the Chernobyl accident consequences revealed that a considerable fraction of radioactivity is accumulated in minute soil grains. So, the separation of contaminated soil by size fractions makes it possible to extract and concentrate the major share of radioactivity in the fine fraction. Based on these researches water gravity separation technology was proposed by Bochvar Institute. The method extracts the fine fraction from contaminated soil. Studies carried out by Bochvar Institute experts showed that, together with the fine fraction (amounting to 10-20% of the initial soil), this technology can remove up to 85-90% of contaminating radionuclides. The resulting 'dirty' soil fraction could be packaged into containers and removed as radwaste, and decontaminated fractions returned back to their extraction site. Use of radiological and water gravity separations consequently increases the productivity of decontamination facility. Efficiency of this technology applied for contaminated soil cleanup was confirmed in the course of remediation of the contaminated territories near decommissioning research reactor in the Kurchatov Institute. For soil cleaning purposes, a special facility implementing the technology of water gravity separation and radiometric monitoring of soil

[Radiation ecological environment in the Republic of Kazakhstan in the vicinity of the reactors and on the territory of the Semipalatinsk Test Site].

Science.gov (United States)

Kim, D S

2012-01-01

The results of research into the environmental conditions in the regions of location of the pressurized water reactor WWR-K, fast neutron breeder BN-350 and on the territory of the Semipalatinsk Test Site are represented. The effects of the exposure to aerosol emissions from WWR-K and BN-350 reactors on the environment are summarized. We present some arguments in favor of the safe operation of fission reactors in compliance with the rules and norms of nuclear and radiation protection and the efficient disposal of radioactive waste on the territory of the Republic.

On-Site Determination and Monitoring of Real-Time Fluence Delivery for an Operating UV Reactor Based on a True Fluence Rate Detector.

Science.gov (United States)

Li, Mengkai; Li, Wentao; Qiang, Zhimin; Blatchley, Ernest R

2017-07-18

At present, on-site fluence (distribution) determination and monitoring of an operating UV system represent a considerable challenge. The recently developed microfluorescent silica detector (MFSD) is able to measure the approximate true fluence rate (FR) at a fixed position in a UV reactor that can be compared with a FR model directly. Hence it has provided a connection between model calculation and real-time fluence determination. In this study, an on-site determination and monitoring method of fluence delivery for an operating UV reactor was developed. True FR detectors, a UV transmittance (UVT) meter, and a flow rate meter were used for fundamental measurements. The fluence distribution, as well as reduction equivalent fluence (REF), 10th percentile dose in the UV fluence distribution (F 10 ), minimum fluence (F min ), and mean fluence (F mean ) of a test reactor, was calculated in advance by the combined use of computational fluid dynamics and FR field modeling. A field test was carried out on the test reactor for disinfection of a secondary water supply. The estimated real-time REF, F 10 , F min , and F mean decreased 73.6%, 71.4%, 69.6%, and 72.9%, respectively, during a 6-month period, which was attributable to lamp output attenuation and sleeve fouling. The results were analyzed with synchronous data from a previously developed triparameter UV monitoring system and water temperature sensor. This study allowed demonstration of an accurate method for on-site, real-time fluence determination which could be used to enhance the security and public confidence of UV-based water treatment processes.

UNDERWATER ANALYSIS OF IRRADIATED REACTOR SLUGS FOR Co-60 AND OTHER RADIONUCLIDES AT THE SAVANNAH RIVER SITE

International Nuclear Information System (INIS)

CASELLA, VITO

2004-01-01

Co-60 was produced in the Savannah River Site (SRS) reactors in the 1970s, and the irradiated cobalt reactor slugs were stored in a reactor basin at SRS. Since the activity rates of these slugs were not accurately known, assaying was required. A sodium iodide gamma detector was placed above a specially designed air collimator assembly, so that the slug was eight to nine feet from the detector and was shielded by the basin water. Also, 18 curium sampler slugs, used to produce Cm-244 from Pu-239, were to be disposed of with the cobalt slugs. The curium slugs were also analyzed with a High Purity Germanium (HPGE) detector in an attempt to identify any additional radionuclides produced from the irradiation. Co-60 concentrations were determined for reactor disassembly basin cobalt slugs and the 18 curium sampler slugs. The total Co-60 activity of all of the assayed slugs in this work summed to 31,783 curies on 9/15/03. From the Co-60 concentrations of the curium sampler slugs, the irradiation flux was determined for the known irradiation time. The amounts of Pu-238,-239,-240,-241,-242; Am-241,-243; and Cm-242,-244 produced were then obtained based on the original amount of Pu-239 irradiated

Preliminary Evaluation of Removing Used Nuclear Fuel from Shutdown Sites

Energy Technology Data Exchange (ETDEWEB)

Maheras, Steven J.; Best, Ralph E.; Ross, Steven B.; Buxton, Kenneth A.; England, Jeffery L.; McConnell, Paul E.

2013-09-30

This report fulfills the M2 milestone M2FT-13PN0912022, “Stranded Sites De-Inventorying Report.” In January 2013, the U.S. Department of Energy (DOE) issued the Strategy for the Management and Disposal of Used Nuclear Fuel and High-Level Radioactive Waste (DOE 2013). Among the elements contained in this strategy is an initial focus on accepting used nuclear fuel from shutdown reactor sites. This focus is consistent with the recommendations of the Blue Ribbon Commission on America’s Nuclear Future, which identified removal of stranded used nuclear fuel at shutdown sites as a priority so that these sites may be completely decommissioned and put to other beneficial uses (BRC 2012). Shutdown sites are defined as those commercial nuclear power reactor sites where the nuclear power reactors have been shut down and the site has been decommissioned or is undergoing decommissioning. In this report, a preliminary evaluation of removing used nuclear fuel from 12 shutdown sites was conducted. The shutdown sites were Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, Zion, Crystal River, Kewaunee, and San Onofre. These sites have no other operating nuclear power reactors at their sites and have also notified the U.S. Nuclear Regulatory Commission that their reactors have permanently ceased power operations and that nuclear fuel has been permanently removed from their reactor vessels. Shutdown reactors at sites having other operating reactors are not included in this evaluation.

Research reactor standards and their impact on the TRIGA reactor community

International Nuclear Information System (INIS)

Richards, W.J.

1980-01-01

The American Nuclear Society has established a standards committee devoted to writing standards for research reactors. This committee was formed in 1971 and has since that time written over 15 standards that cover all aspects of research reactor operation. The committee has representation from virtually every group concerned with research reactors and their operation. This organization includes University reactors, National laboratory reactors, Nuclear Regulatory commission, Department of Energy and private nuclear companies and insurers. Since its beginning the committee has developed standards in the following areas: Standard for the development of technical specifications for research reactors; Quality control for plate-type uranium-aluminium fuel elements; Records and reports for research reactors; Selection and training of personnel for research reactors; Review of experiments for research reactors; Research reactor site evaluation; Quality assurance program requirements for research reactors; Decommissioning of research reactors; Radiological control at research reactor facilities; Design objectives for and monitoring of systems controlling research reactor effluents; Physical security for research reactor facilities; Criteria for the reactor safety systems of research reactors; Emergency planning for research reactors; Fire protection program requirements for research reactors; Standard for administrative controls for research reactors. Besides writing the above standards, the committee is very active in using communications with the nuclear regulatory commission on proposed rules or positions which will affect the research reactor community

Dose rate in the reactor room and environment during maintenance in fusion reactors

International Nuclear Information System (INIS)

Maki, Koichi; Satoh, Satoshi; Takatsu, Hideyuki; Seki, Yasushi

1995-01-01

According to the International Thermonuclear Experimental Reactor (ITER) conceptual design activity, after reactor shutdown, damaged segments are pulled up from the reactor and hung from the reactor room ceiling by a remote handling device. The dose rate in the reactor room and the environment is estimated for this situation, and the following results are obtained. First, the dose rate in the room is > 10 8 μSv/h. Since this dose rate is 10 7 times greater than the biological radiation shielding design limit of 25 μSv/h, workers cannot enter the room. Second, lenses and optical fiber composed of glass that is radiation resistant up to 10 6 Gy would be damaged after <100 h near the segment, and devices using semiconductors could not work after several hours or so in the aforementioned dose-rate conditions. Third, during suspension of one blanket segment from the ceiling, the dose rate in the site boundary can be reduced by one order by a 23-cm-thicker reactor building roof. To reduce dose rate in public exposure to a value that is less than one-tenth of the public exposure radiation shielding design limit of 100 μSv/yr, the distance of the site boundary from the reactor must be greater than 200 m for a reactor building with a 160-cm-thick concrete roof. 9 refs., 6 figs., 2 tabs

Experimental studies of U-Pu-Zr fast reactor fuel pins in EBR-II [Experimental Breeder Reactor

International Nuclear Information System (INIS)

Pahl, R.G.; Porter, D.L.; Lahm, C.E.; Hofman, G.L.

1988-01-01

The Integral Fast Reactor (IFR) is a generic reactor concept under development by Argonne National Laboratory. Much of the technology for the IFR is being demonstrated at the Experimental Breeder Reactor II (EBR-II) on the Department of Energy site near Idaho Falls, Idaho. The IFR concept relies on four technical features to achieve breakthroughs in nuclear power economics and safety: (1) a pool-type reactor configuration, (2) liquid sodium cooling, (3) metallic fuel, and (4) an integral fuel cycle with on-site reprocessing. The purpose of this paper will be to summarize our latest results of irradiation testing uranium-plutonium-zirconium (U-Pu-Zr) fuel in the EBR-II. 10 refs., 13 figs., 2 tabs

2016 Annual Inspection and Radiological Survey Results for the Piqua, Ohio, Decommissioned Reactor Site, July 2016

Energy Technology Data Exchange (ETDEWEB)

Zimmerman, Brian [USDOE Office of Legacy Management, Washington, DC (United States); Miller, Michele [Navarro Research and Engineering, Oak Ridge, TN (United States)

2016-07-01

This report presents the findings of the annual inspection and radiological survey of the Piqua, Ohio, Decommissioned Reactor Site (site). The decommissioned nuclear power demonstration facility was inspected and surveyed on April 15, 2016. The site, located on the east bank of the Great Miami River in Piqua, Ohio, was in fair physical condition. There is no requirement for a follow-up inspection, partly because City of Piqua (City) personnel participated in a March 2016 meeting to address reoccurring safety concerns. Radiological survey results from 104 locations revealed no removable contamination. One direct beta activity reading in a floor drain on the 56-foot level (1674 disintegrations per minute [dpm]/100 square centimeters [cm2]) exceeded the minimum detectable activity (MDA). Beta activity has been detected in the past at this floor drain. The reading was well below the action level of 5000 dpm/100 cm2.

Status of the RA research reactor decommissioning project

International Nuclear Information System (INIS)

Ljubenov, V.; Nikolic, D.; Pesic, M.; Milosevic, M.; Kostic, Lj.; Steljic, M.; Sotic, O.; Antic, D. . E-mail address of corresponding author: vladan@vin.bg.ac.yu; Ljubenov, V.)

2005-01-01

The 6.5 MW heavy water RA research reactor at the VINCA Institute of Nuclear Sciences operated from 1959 to 1984. After 18 years of extended shutdown in 2002 it was decided that the reactor shutdown should be final. Preliminary decommissioning activities have been initiated by the end of 2002 under the Technical Co-operation Programme of the International Atomic Energy Agency. The objective of the project is to implement safe, timely and cost-effective decommissioning of the RA reactor up to unrestricted use of the site. Decommissioning project is closely related to two other projects: Safe Removal of the RA Reactor Spent Nuclear Fuel and Radioactive Waste Management in VINCA Institute. The main phases of the project include preparation of the detailed decommissioning plan, radiological characterization of the reactor site, dismantling and removal of the reactor components and structures, decontamination, final radiological site survey and the documentation of all the activities in order to obtain the approval for unrestricted use of the facility site. In this paper a review of the activities related to the preparation and realization of the RA reactor decommissioning project is given. Status of the project's organizational and technical aspects as for July 2004 are presented and plans for the forthcoming phases of the project realization are outlined. (author)

Licensed reactor nuclear safety criteria applicable to DOE reactors

International Nuclear Information System (INIS)

1991-04-01

The Department of Energy (DOE) Order DOE 5480.6, Safety of Department of Energy-Owned Nuclear Reactors, establishes reactor safety requirements to assure that reactors are sited, designed, constructed, modified, operated, maintained, and decommissioned in a manner that adequately protects health and safety and is in accordance with uniform standards, guides, and codes which are consistent with those applied to comparable licensed reactors. This document identifies nuclear safety criteria applied to NRC [Nuclear Regulatory Commission] licensed reactors. The titles of the chapters and sections of USNRC Regulatory Guide 1.70, Standard Format and Content of Safety Analysis Reports for Nuclear Power Plants, Rev. 3, are used as the format for compiling the NRC criteria applied to the various areas of nuclear safety addressed in a safety analysis report for a nuclear reactor. In each section the criteria are compiled in four groups: (1) Code of Federal Regulations, (2) US NRC Regulatory Guides, SRP Branch Technical Positions and Appendices, (3) Codes and Standards, and (4) Supplemental Information. The degree of application of these criteria to a DOE-owned reactor, consistent with their application to comparable licensed reactors, must be determined by the DOE and DOE contractor

Decommissioning of TRIGA Mark II type reactor

Energy Technology Data Exchange (ETDEWEB)

Hwang, Dooseong; Jeong, Gyeonghwan; Moon, Jeikwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2012-10-15

The first research reactor in Korea, KRR 1, is a TRIGA Mark II type with open pool and fixed core. Its power was 100 kWth at its construction and it was upgraded to 250 kWth. Its construction was started in 1957. The first criticality was reached in 1962 and it had been operated for 36,000 hours. The second reactor, KRR 2, is a TRIGA Mark III type with open pool and movable core. These reactors were shut down in 1995, and the decision was made to decommission both reactors. The aim of the decommissioning activities is to decommission the KRR 2 reactor and decontaminate the residual building structures and site, and to release them as unrestricted areas. The KRR 1 reactor was decided to be preserve as a historical monument. A project was launched for the decommissioning of these reactors in 1997, and approved by the regulatory body in 2000. A total budget for the project was 20.0 million US dollars. It was anticipated that this project would be completed and the site turned over to KEPCO by 2010. However, it was discovered that the pool water of the KRR 1 reactor was leaked into the environment in 2009. As a result, preservation of the KRR 1 reactor as a monument had to be reviewed, and it was decided to fully decommission the KRR 1 reactor. Dismantling of the KRR 1 reactor takes place from 2011 to 2014 with a budget of 3.25 million US dollars. The scope of the work includes licensing of the decommissioning plan change, removal of pool internals including the reactor core, removal of the thermal and thermalizing columns, removal of beam port tubes and the aluminum liner in the reactor tank, removal of the radioactive concrete (the entire concrete structure will not be demolished), sorting the radioactive waste (concrete and soil) and conditioning the radioactive waste for final disposal, and final statuses of the survey and free release of the site and building, and turning over the site to KEPCO. In this paper, the current status of the TRIGA Mark-II type reactor

Methods and strategies for future reactor safety goals

Science.gov (United States)

Arndt, Steven Andrew

There have been significant discussions over the past few years by the United States Nuclear Regulatory Commission (NRC), the Advisory Committee on Reactor Safeguards (ACRS), and others as to the adequacy of the NRC safety goals for use with the next generation of nuclear power reactors to be built in the United States. The NRC, in its safety goals policy statement, has provided general qualitative safety goals and basic quantitative health objectives (QHOs) for nuclear reactors in the United States. Risk metrics such as core damage frequency (CDF) and large early release frequency (LERF) have been used as surrogates for the QHOs. In its review of the new plant licensing policy the ACRS has looked at the safety goals, as has the NRC. A number of issues have been raised including what the Commission had in mind when it drafted the safety goals and QHOs, how risk from multiple reactors at a site should be combined for evaluation, how the combination of a new and old reactor at the same site should be evaluated, what the criteria for evaluating new reactors should be, and whether new reactors should be required to be safer than current generation reactors. As part of the development and application of the NRC safety goal policy statement the Commissioners laid out the expectations for the safety of a nuclear power plant but did not address the risk associated with current multi-unit sites, potential modular reactor sites, and hybrid sites that could contain current generation reactors, new passive reactors, and/or modular reactors. The NRC safety goals and the QHOs refer to a "nuclear power plant," but do not discuss whether a "plant" refers to only a single unit or all of the units on a site. There has been much discussion on this issue recently due to the development of modular reactors. Additionally, the risk of multiple reactor accidents on the same site has been largely ignored in the probabilistic risk assessments (PRAs) done to date, and in most risk

Removal Site Evaluation Report to the C-Reactor Seepage Basins (904-066, -067 and -068G)

Energy Technology Data Exchange (ETDEWEB)

Palmer, E.R. [Westinghouse Savannah River Company, AIKEN, SC (United States)

1997-07-01

Removal Site Evaluation Reports are prepared in accordance with Section 300.410 of the National Contingency Plan (NCP) and Section X of the Federal Facility Agreement (FFA). The C-Reactor Seepage Basins (904-066G,-067G,-068G) are listed in Appendix C, Resource Conservation and Recovery Act (RCRA)/Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Units List, of the FFA. The purpose of this investigation is to report information concerning conditions at this unit sufficient to assess the threat (if any) posed to human health and the environment and to determine the need for additional CERCLA action. The scope of the investigation included a review of past survey and investigation data, the files, and a visit to the unit.Through this investigation unacceptable conditions of radioactive contaminant uptake in on-site vegetation were identified. This may have resulted in probable contaminant migration and become introduced into the local ecological food chain. As a result, the SRS will initiate a time critical removal action in accordance with Section 300.415 of the NCP and FFA Section XIV to remove, treat (if required), and dispose of contaminated vegetation from the C-Reactor Seepage Basins. Erosion in the affected areas will be managed by an approved erosion control plan. further remediation of this unit will be conducted in accordance with the FFA.

Removal Site Evaluation Report to the C-Reactor Seepage Basins (904-066, -067 and -068G)

International Nuclear Information System (INIS)

Palmer, E.R.

1997-07-01

Removal Site Evaluation Reports are prepared in accordance with Section 300.410 of the National Contingency Plan (NCP) and Section X of the Federal Facility Agreement (FFA). The C-Reactor Seepage Basins (904-066G,-067G,-068G) are listed in Appendix C, Resource Conservation and Recovery Act (RCRA)/Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Units List, of the FFA. The purpose of this investigation is to report information concerning conditions at this unit sufficient to assess the threat (if any) posed to human health and the environment and to determine the need for additional CERCLA action. The scope of the investigation included a review of past survey and investigation data, the files, and a visit to the unit.Through this investigation unacceptable conditions of radioactive contaminant uptake in on-site vegetation were identified. This may have resulted in probable contaminant migration and become introduced into the local ecological food chain. As a result, the SRS will initiate a time critical removal action in accordance with Section 300.415 of the NCP and FFA Section XIV to remove, treat (if required), and dispose of contaminated vegetation from the C-Reactor Seepage Basins. Erosion in the affected areas will be managed by an approved erosion control plan. further remediation of this unit will be conducted in accordance with the FFA

Decommissioning of the Dragon High Temperature Reactor (HTR) Located at the Former United Kingdom Atomic Energy Authority (UKAEA) Research Site at Winfrith - 13180

Energy Technology Data Exchange (ETDEWEB)

Smith, Anthony A. [Research Sites Restoration Ltd, Winfrith, Dorset (United Kingdom)

2013-07-01

The Dragon Reactor was constructed at the United Kingdom Atomic Energy Research Establishment at Winfrith in Dorset through the late 1950's and into the early 1960's. It was a High Temperature Gas Cooled Reactor (HTR) with helium gas coolant and graphite moderation. It operated as a fuel testing and demonstration reactor at up to 20 MW (Thermal) from 1964 until 1975, when international funding for this project was terminated. The fuel was removed from the core in 1976 and the reactor was put into Safestore. To meet the UK's Nuclear Decommissioning Authority (NDA) objective to 'drive hazard reduction' [1] it is necessary to decommission and remediate all the Research Sites Restoration Ltd (RSRL) facilities. This includes the Dragon Reactor where the activated core, pressure vessel and control rods and the contaminated primary circuit (including a {sup 90}Sr source) still remain. It is essential to remove these hazards at the appropriate time and return the area occupied by the reactor to a safe condition. (author)

A future for nuclear sites beyond their service life. Nuclear site value development; Un avenir pour les sites nucleaires en fin de cycle. Valorisation des sites nucleaires

Energy Technology Data Exchange (ETDEWEB)

NONE

2008-07-01

As the nuclear industry moves into a new development phase, many facilities built in the fifties and sixties are reaching the end of their service life. Dismantling them and rehabilitating the sites on which they stand is a major industrial challenge which will give rise to a number of new projects. AREVA has more than 20 years' experience in these highly technical fields. As more and more sites reach the end of their service life, AREVA considers nuclear site value development as a fully-fledged industrial activity. The group's competencies in this field have been grouped together to form a dedicated entity: the Nuclear Site Value Development Business Unit, created in 2008. Several billion euros are invested in site value development projects which are far-reaching and complex, and often last for several decades. Long before work actually begins, lengthy studies and preparations are required to schedule operations, select the techniques to be used and optimize costs and deadlines. The Nuclear Site Value Development BU is currently working on four major projects involving its own facilities and those of the CEA: - La Hague: dismantling of the first generation of used fuel recycling facilities. Between 1966 and 1998, almost 5,000 tons of used fuel from graphite-moderated gas-cooled reactors, 4,500 tons of light water reactor fuel, as well as fuel from fast reactors and research reactors, were treated at UP2 400, the very first industrial recycling plant on the La Hague site. - Marcoule: first-time dismantling of a recycling plant. 1,000 rooms to be cleaned up, 30,000 tons of waste to be treated, 30 years of work. - Cadarache: first-time dismantling of a Mox fuel fabrication plant. The Cadarache plant was commissioned in 1962 to fabricate fuel for fast reactors; this was followed by MOX fuel for light water reactors, an activity which continued until the plant was shut down in 2003. - Annecy and Veurey: giving a new lease of life to former industrial sites

Reactor operation safety information document

Energy Technology Data Exchange (ETDEWEB)

1990-01-01

The report contains a reactor facility description which includes K, P, and L reactor sites, structures, operating systems, engineered safety systems, support systems, and process and effluent monitoring systems; an accident analysis section which includes cooling system anomalies, radioactive materials releases, and anticipated transients without scram; a summary of onsite doses from design basis accidents; severe accident analysis (reactor core disruption); a description of operating contractor organization and emergency planning; and a summary of reactor safety evolution. (MB)

Safeguarding research reactors

International Nuclear Information System (INIS)

Powers, J.A.

1983-03-01

The report is organized in four sections, including the introduction. The second section contains a discussion of the characteristics and attributes of research reactors important to safeguards. In this section, research reactors are described according to their power level, if greater than 25 thermal megawatts, or according to each fuel type. This descriptive discussion includes both reactor and reactor fuel information of a generic nature, according to the following categories. 1. Research reactors with more than 25 megawatts thermal power, 2. Plate fuelled reactors, 3. Assembly fuelled reactors. 4. Research reactors fuelled with individual rods. 5. Disk fuelled reactors, and 6. Research reactors fuelled with aqueous homogeneous fuel. The third section consists of a brief discussion of general IAEA safeguards as they apply to research reactors. This section is based on IAEA safeguards implementation documents and technical reports that are used to establish Agency-State agreements and facility attachments. The fourth and last section describes inspection activities at research reactors necessary to meet Agency objectives. The scope of the activities extends to both pre and post inspection as well as the on-site inspection and includes the examination of records and reports relative to reactor operation and to receipts, shipments and certain internal transfers, periodic verification of fresh fuel, spent fuel and core fuel, activities related to containment and surveillance, and other selected activities, depending on the reactor

Research reactor back-end options - decommissioning: a necessary consideration

International Nuclear Information System (INIS)

England, M.R.; Parry, D.R.; Smith, C.

1998-01-01

Decommissioning is a challenge, which all radioactive site licensees eventually need to face and research reactors are no exception. BNFL has completed numerous major decommissioning projects at its own operational sites and has undertaken similar works at customers' sites including the decommissioning of the Universities Research Reactor (URR), Risley and the ICI TRIGA 1-Mk I Reactor at Billingham. Based on the execution of such projects BNFL has gained an understanding of the variety of customer requirements and the effectiveness of specific decommissioning techniques for research reactors. This paper addresses factors to be considered when reviewing the way forward following shut down and how these affect the final decisions for fuel management and the extent of decommissioning. Case studies are described from BNFL's recent experience decommissioning both the URR and ICI TRIGA reactors. (author)

Safety of Research Reactors. Safety Requirements

International Nuclear Information System (INIS)

2010-01-01

The main objective of this Safety Requirements publication is to provide a basis for safety and a basis for safety assessment for all stages in the lifetime of a research reactor. Another objective is to establish requirements on aspects relating to regulatory control, the management of safety, site evaluation, design, operation and decommissioning. Technical and administrative requirements for the safety of research reactors are established in accordance with these objectives. This Safety Requirements publication is intended for use by organizations engaged in the site evaluation, design, manufacturing, construction, operation and decommissioning of research reactors as well as by regulatory bodies

Neutron activation analysis in an industrial laboratory using an off-site nuclear reactor

International Nuclear Information System (INIS)

Osborn, T.W.; Broering, W.B.

1977-01-01

A multifunctional research laboratory, such as Procter and Gamble's Miami Valley Laboratories, requires elemental analyses on many materials. A general survey technique is important even if the information it provides is incomplete or is less precise than single element analyses. Procter and Gamble has developed neutron activation analysis (NAA) capabilities using a nuclear reactor several hundred miles away. The concentration of 40 to 50 elements can be determined in a variety of matrices. We have found NAA to be a powerful supplement to some of the more classical analytical techniques even without having an on-site neutron source. We have also found an automated data acquisition system to be essential for the successful application of NAA in an industrial laboratory

Conceptual design of a large heavy water reactor for US siting

International Nuclear Information System (INIS)

Shapiro, N.L.; Jesick, J.F.

1979-09-01

Information is presented concerning fuel management and safety and licensing assessment of the pressurized heavy water reactor; and commercial introduction of the pressurized heavy water reactor in the United States

Reactor FaceMap Tool: A modern graphics tool for displaying reactor data

International Nuclear Information System (INIS)

Roberts, J.C.

1991-01-01

A prominent graphical user interface in reactor physics applications at the Savannah River Site is the reactor facemap display. This is a two dimensional view of a cross section of a reactor. In the past each application which needed a facemap implemented its own version. Thus, none of the code was reused, the facemap implementation was hardware dependent and the user interface was different for each facemap. The Reactor FaceMap Tool was built to solve these problems. Through the use of modern computing technologies such as X Windows, object-oriented programming and client/server technology the Reactor FaceMap Tool has the flexibility to work in many diverse applications and the portability to run on numerous types of hardware

On-site experimental dynamic analysis for evaluating the soil-structure interaction and the seismic behaviour of the Italian PEC fast reactor building

International Nuclear Information System (INIS)

Casirati, M.; Castoldi, A.; Panzeri, P.; Pezzoli, P.; Martelli, A.; Masoni, P.; Brancati, V.

1988-01-01

The paper describes the on-site dynamic tests carried out on the PEC fast reactor building, using various excitation methods (two eccentric back-rotating-mass mechanical vibrator, blasting in bore-hole, hydraulic actuators at the building foundations). It points out the purposes of the four tests campaigns performed at various construction stages and reports the main experimental results. These results concern both the design safety margins and the data for the validation of the three-dimensional numerical model of the reactor building, including soil-structure interaction phenomena. (author)

Siting Practices and Site Licensing Process for New Reactors in Canada

International Nuclear Information System (INIS)

Vos, Marcel de

2011-01-01

'Siting' in Canada is composed of Site Evaluation and Site Selection. As outlined in CNSC Regulatory Document RD-346 Site Evaluation for New Nuclear Power Plants (based on IAEA NS-R-3), prior to the triggering of the Environmental Assessment (EA) and licensing processes, the proponent is expected to use a robust process to characterize proposed sites over the full life cycle of the facility, and then develop a fully documented defense of the site selection case. This case forms the backbone for submissions in support of the EA and the application for a License to Prepare Site which will be reviewed by the CNSC and other applicable federal authorities. The Environmental Assessment process and License to Prepare Site in Canada do not require a proponent to select a specific design; however, CNSC does not accept a 'black box' approach to siting. CNSC balances the level of design information required with the extent of safety assurance desired for any designs being contemplated for the proposed site. Nevertheless, the design information submitted must be sufficient to justify the site as suitable for all future licensing stages. The depth of plant design information contributes significantly to the credibility of the applicant's case for both the EA and application for License to Prepare Site. The review process utilizes an assessment plan with defined review stages and timelines. The outcome of these reviews is a series of recommendations to a federal government appointed Joint Review Panel (which also serves as a panel of the 'Commission') which, following public hearings, renders a decision regarding the EA, and subsequently, the application for a License to Prepare Site. (author)

Reactor decommissioning strategy: a new start for BNFL

International Nuclear Information System (INIS)

Woollam, P.; Nurden, P.

2001-01-01

The key points of BNFL Magnox Electric's revised waste management and reactor decommissioning strategy for the reactor sites are enlisted. Reactors will be defuelled as soon as practicable after shutdown. Predominantly Caesium contaminated plant will be dismantled when it is no longer needed. Cobalt contaminated plant such as boilers will remain in position until the reactors are dismantled, but appropriate decontamination technology will be regularly reviewed. All buildings except the reactor buildings will be dismantled as soon as practicable after they are no longer needed. Operational ILW, except some activated components, will be retrieved and packaged during the Care and Maintenance preparation period. All wastes will be stored on site, and handled in the long term in accordance with Government policy. Reactor buildings and their residual contents will be placed in a passive safe storage Care and Maintenance condition in a manner appropriate for the site. Contaminated land will be managed to maintain public safety. The reactors will be finally dismantled in a sequenced programme with a start date and duration to be decided at the appropriate time in the light of circumstances prevalent at that time. Currently, the Company is considering a sequenced programme across all sites, notionally beginning around 100 years from station shutdown, leading to a range of deferral periods. For provisioning purposes, the Company has costed a strategy involving reactor dismantling deferrals ranging from 85 to about 105 years in order to demonstrate prudent provisioning to meet its liabilities. A risk provision to reflect the potential for shorter deferral periods is included in the cost estimates. The end point for reactor decommissioning is site clearance and delicensing, based on the assumption that a reasonably practicable interpretation of the 'no danger' clause in the Nuclear Installations Act 1965 (as amended) can be developed. In line with Government policy, and taking

Research reactor spent fuel management in Argentina

International Nuclear Information System (INIS)

Audero, M.A.; Bevilacqua, A.M.; Mehlich, A.M.; Novara, O.

2002-01-01

The research reactor spent fuel (RRSF) management strategy will be presented as well as the interim storage experience. Currently, low-enriched uranium RRSF is in wet interim storage either at reactor site or away from reactor site in a centralized storage facility. High-enriched uranium RRSF from the centralized storage facility has been sent to the USA in the framework of the Foreign Research Reactor Spent Nuclear Fuel Acceptance Program. The strategy for the management of the RRSF could implement the encapsulation for interim dry storage. As an alternative to encapsulation for dry storage some conditioning processes are being studied which include decladding, isotopic dilution, oxidation and immobilization. The immobilized material will be suitable for final disposal. (author)

The Maple reactor project

International Nuclear Information System (INIS)

Malkoske, G.R.; Labrie, J.-P.

2003-01-01

MDS Nordion supplies the majority of the world's reactor-produced medical isotopes. These isotopes are currently produced in the NRU reactor at AECL's Chalk River Laboratories (CRL). Medical isotopes and related technology are relied upon around the world to prevent, diagnose and treat disease. The NRU reactor, which has played a key role in supplying medical isotopes to date, has been in operation for over 40 years. Replacing this aging reactor has been a priority for MDS Nordion to assure the global nuclear medicine community that Canada will continue to be a dependable supplier of medical isotopes. MDS Nordion contracted AECL to construct two MAPLE reactors dedicated to the production of medical isotopes. The MDS Nordion Medical Isotope Reactor (MMIR) project started in September 1996. This paper describes the MAPLE reactors that AECL has built at its CRL site, and will operate for MDS Nordion. (author)

Economic impacts on the United States of siting decisions for the International Thermonuclear Experimental Reactor

International Nuclear Information System (INIS)

Peerenboom, J.P.; Wolsko, T.D.; Hanson, M.E.

1997-01-01

This paper presents the results of a study that examines and compares the probable short-term economic impacts of the International Thermonuclear Experimental Reactor (ITER) on the United States (U.S.) if (1) ITER were to be sited in the U.S., or (2) ITER were to be sited in one of the other countries that along with the U.S., is currently participating in the ITER program. Life-cycle costs associated with ITER construction, operation, and decommissioning are analyzed to assess their economic impact. A number of possible U.S. host and U.S. non-host technology and cost-sharing arrangements with the other ITER Parties are examined, although cost-sharing arrangements and the process by which the Parties will select a host country and an ITER site remain open issues. Both national and local/regional economic impacts, as measured by gross domestic product, regional output, employment, net exports, and income, are considered. These impacts represent a portion of the complex, interrelated set of economic considerations that characterize U.S. host and U.S. non-host participation in ITER. A number of other potentially important economic and noneconomic considerations are discussed qualitatively

Economic impacts on the United States of siting decisions for the international thermonuclear experimental reactor

International Nuclear Information System (INIS)

Peerenboom, J.P.; Hanson, M.E.; Huddleston, J.R.

1996-08-01

This report presents the results of a study that examines and compares the probable short-term economic impacts of the International Thermonuclear Experimental Reactor (ITER) on the United States (U.S.) if (1) ITER were to be sited in the U.S., or (2) ITER were to be sited in one of the other countries that, along with the U.S., is currently participating in the ITER program. Life-cycle costs associated with ITER construction, operation, and decommissioning are analyzed to assess their economic impact. A number of possible U.S. host and U.S. non-host technology and cost-sharing arrangements with the other ITER Parties are examined, although cost-sharing arrangements and the process by which the Parties will select a host country and an ITER site remain open issues. Both national and local/regional economic impacts, as measured by gross domestic product, regional output, employment, net exports, and income, are considered. These impacts represent a portion of the complex, interrelated set of economic considerations that characterize U.S. host and U.S. non-host participation in ITER. A number of other potentially important economic and noneconomic considerations are discussed qualitatively

Economic impacts on the United States of siting decisions for the international thermonuclear experimental reactor

Energy Technology Data Exchange (ETDEWEB)

Peerenboom, J.P.; Hanson, M.E.; Huddleston, J.R. [and others

1996-08-01

This report presents the results of a study that examines and compares the probable short-term economic impacts of the International Thermonuclear Experimental Reactor (ITER) on the United States (U.S.) if (1) ITER were to be sited in the U.S., or (2) ITER were to be sited in one of the other countries that, along with the U.S., is currently participating in the ITER program. Life-cycle costs associated with ITER construction, operation, and decommissioning are analyzed to assess their economic impact. A number of possible U.S. host and U.S. non-host technology and cost-sharing arrangements with the other ITER Parties are examined, although cost-sharing arrangements and the process by which the Parties will select a host country and an ITER site remain open issues. Both national and local/regional economic impacts, as measured by gross domestic product, regional output, employment, net exports, and income, are considered. These impacts represent a portion of the complex, interrelated set of economic considerations that characterize U.S. host and U.S. non-host participation in ITER. A number of other potentially important economic and noneconomic considerations are discussed qualitatively.

Safety performance comparation of MOX, nitride and metallic fuel based 25-100 MWe Pb-Bi cooled long life fast reactors without on-site refuelling

International Nuclear Information System (INIS)

Su'ud, Zaki

2008-01-01

In this paper the safety performance of 25-100 MWe Pb-Bi cooled long life fast reactors based on three types of fuels: MOX, nitride and metal is compared and discussed. In the fourth generation NPP paradigm, especially for Pb-Bi cooled fast reactors, inherent safety capability is necessary against some standard accidents such as unprotected loss of flow (ULOF), unprotected rod run-out transient over power (UTOP), unprotected loss of heat sink (ULOHS). Selection of fuel type will have important impact on the overall system safety performance. The results of safety analysis of long life Pb-Bi cooled fast reactors without on-site fuelling using nitride, MOX and metal fuel have been performed. The reactors show the inherent safety pattern with enough safety margins during ULOF and UTOP accidents. For MOX fuelled reactors, ULOF accident is more severe than UTOP accident while for nitride fuelled cores UTOP accident may push power much higher than that comparable MOX fuelled cores. (author)

Decommissioning an Active Historical Reactor Facility at the Savannah River Site - 13453

Energy Technology Data Exchange (ETDEWEB)

Bergren, Christopher L.; Long, J. Tony; Blankenship, John K. [Savannah River Nuclear Solutions, LLC, Bldg. 730-4B, Aiken, SC 29808 (United States); Adams, Karen M. [United States Department of Energy, Bldg. 730-B, Aiken, SC 29808 (United States)

2013-07-01

The Savannah River Site (SRS) is an 802 square-kilometer United States Department of Energy (US DOE) nuclear facility located along the Savannah River near Aiken, South Carolina, where Management and Operations are performed by Savannah River Nuclear Solutions (SRNS). In 2004, DOE recognized SRS as structure within the Cold War Historic District of national, state and local significance composed of the first generation of facilities constructed and operated from 1950 through 1989 to produce plutonium and tritium for our nation's defense. DOE agreed to manage the SRS 105-C Reactor Facility as a potentially historic property due to its significance in supporting the U.S. Cold War Mission and for potential for future interpretation. This reactor has five primary areas within it, including a Disassembly Basin (DB) that received irradiated materials from the reactor, cooled them and prepared the components for loading and transport to a Separation Canyon for processing. The 6,317 square meter area was divided into numerous work/storage areas. The walls between the individual basin compartments have narrow vertical openings called 'slots' that permit the transfer of material from one section to another. Data indicated there was over 830 curies of radioactivity associated with the basin sediments and approximately 9.1 M liters of contaminated water, not including a large quantity of activated reactor equipment, scrap metal, and debris on the basin floor. The need for an action was identified in 2010 to reduce risks to personnel in the facility and to eliminate the possible release of contaminants into the environment. The release of DB water could potentially migrate to the aquifer and contaminate groundwater. DOE, its regulators [U. S. Environmental Protection Agency (USEPA)-Region 4 and the South Carolina Department of Health and Environmental Control (SCDHEC)] and the SC Historical Preservation Office (SHPO) agreed/concurred to perform a non

Decommissioning an Active Historical Reactor Facility at the Savannah River Site - 13453

International Nuclear Information System (INIS)

Bergren, Christopher L.; Long, J. Tony; Blankenship, John K.; Adams, Karen M.

2013-01-01

The Savannah River Site (SRS) is an 802 square-kilometer United States Department of Energy (US DOE) nuclear facility located along the Savannah River near Aiken, South Carolina, where Management and Operations are performed by Savannah River Nuclear Solutions (SRNS). In 2004, DOE recognized SRS as structure within the Cold War Historic District of national, state and local significance composed of the first generation of facilities constructed and operated from 1950 through 1989 to produce plutonium and tritium for our nation's defense. DOE agreed to manage the SRS 105-C Reactor Facility as a potentially historic property due to its significance in supporting the U.S. Cold War Mission and for potential for future interpretation. This reactor has five primary areas within it, including a Disassembly Basin (DB) that received irradiated materials from the reactor, cooled them and prepared the components for loading and transport to a Separation Canyon for processing. The 6,317 square meter area was divided into numerous work/storage areas. The walls between the individual basin compartments have narrow vertical openings called 'slots' that permit the transfer of material from one section to another. Data indicated there was over 830 curies of radioactivity associated with the basin sediments and approximately 9.1 M liters of contaminated water, not including a large quantity of activated reactor equipment, scrap metal, and debris on the basin floor. The need for an action was identified in 2010 to reduce risks to personnel in the facility and to eliminate the possible release of contaminants into the environment. The release of DB water could potentially migrate to the aquifer and contaminate groundwater. DOE, its regulators [U. S. Environmental Protection Agency (USEPA)-Region 4 and the South Carolina Department of Health and Environmental Control (SCDHEC)] and the SC Historical Preservation Office (SHPO) agreed/concurred to perform a non-time critical removal

Emergency medical assistance programs for nuclear power reactors

International Nuclear Information System (INIS)

Linnemann, R.E.; Mettler, F.A. Jr.

1977-01-01

This paper deals with a simple but practical medical support of geographically distributed nuclear reactors in isolated areas. A staff of experts at a centre devote their full attention to accident prevention and preparedness at reactor sites. They establish and maintain emergency medical programs at reactor sites and nearby support hospitals. The emphasis is on first aid and emergency treatment by medical attendants who are not and cannot be experts in radiation but do know how to treat patients. (author)

Achieving the timely receipt of foreign research reactor spent nuclear fuel at the Savannah River site

International Nuclear Information System (INIS)

Brizes, C.M.; Clark, W.D; Thomas, J.; Andes, T.

1998-01-01

The May 1996 Record of Decision on a Proposed Nuclear Weapons Nonproliferation Policy Concerning Foreign Research Reactor Spent Nuclear Fuel states that the United States will accept spent nuclear fuel containing uranium of U.S.-origin from foreign research reactors through the year 2009. The best information available indicates that approximately 13,000 assemblies of Material Test Reactor (MTR) spent nuclear fuel from 29 countries are expected to be shipped to the Savannah River Site during the 13 years of the program. As of July 1998, 1,371 spent nuclear fuel assemblies from 12 foreign research reactors have been received at the SRS. That is, after more than two years of the FRR program (approximately 15 percent of the program time), 11 percent of the total assemblies have been received at SRS. Current projections show that most of the assemblies can be received by 2009, however if some of the eligible, non-participating countries decide to rejoin the program, a bottleneck would occur at the end of the program. Also adding to the potential for the bottleneck is a trend of shipments being moved out in the timeline. The Savannah River Site is working to be proactive in avoiding a bottleneck at the end of the program, but cooperation is required from all program participants to be successful. Activities currently in progress include inventory/information questionnaires, verifying fuel against cask(s) certificate of compliance (C. of C.), and collecting Appendix A information well in advance of shipping the SNF. The inventory/information sheets have been distributed to a select number of reactor facilities in the past, but work is in progress to refine the process. Information requested in the questionnaire includes inventory numbers, preferred shipping dates, and cask preferences. This information allows for improved shipment planning and helps to ensure that we are working to meet the needs of the reactor facilities. Current plans are to send the questionnaires to

Environmental assessment of SP-100 ground engineering system test site: Hanford Site, Richland, Washington

Energy Technology Data Exchange (ETDEWEB)

1988-12-01

The US Department of Energy (DOE) proposes to modify an existing reactor containment building (decommissioned Plutonium Recycle Test Reactor (PRTR) 309 Building) to provide ground test capability for the prototype SP-100 reactor. The 309 Building (Figure 1.1) is located in the 300 Area on the Hanford Site in Washington State. The National Environmental Policy Act (NEPA) requires that Federal agencies assess the potential impacts that their actions may have on the environment. This Environmental Assessment describes the consideration given to environmental impacts during reactor concept and test site selection, examines the environmental effects of the DOE proposal to ground test the nuclear subsystem, describes alternatives to the proposed action, and examines radiological risks of potential SP-100 use in space. 73 refs., 19 figs., 7 tabs.

Technology, safety and costs of decommissioning nuclear reactors at multiple-reactor stations

International Nuclear Information System (INIS)

Wittenbrock, N.G.

1982-01-01

Safety and cost information is developed for the conceptual decommissioning of large (1175-MWe) pressurized water reactors (PWR) and large (1155-MWe) boiling water reactors (BWR) at multiple-reactor stations. Three decommissioning alternatives are studied: DECON (immediate decontamination), SAFSTOR (safe storage followed by deferred decontamination), and ENTOMB (entombment). Safety and costs of decommissioning are estimated by determining the impact of probable features of multiple-reactor-station operation that are considered to be unavailable at a single-reactor station, and applying these estimated impacts to the decommissioning costs and radiation doses estimated in previous PWR and BWR decommissioning studies. The multiple-reactor-station features analyzed are: the use of interim onsite nuclear waste storage with later removal to an offsite waste disposal facility, the use of permanent onsite nuclear waste disposal, the dedication of the site to nuclear power generation, and the provision of centralized services

An assessment of the radiological consequences of accidents in research reactors

International Nuclear Information System (INIS)

Ferreira, N.L.D.

1992-01-01

This work analyses the radiological consequences of accidents in two types of research reactors: a 5 MWt open pool reactor and a 50 MWt PWR reactor. Two siting cases have been considered: the reactor located near to a large population center and sited in a rural area. The influence of several factors such as source term, meteorological conditions and population distribution have been considered in the present analysis. (author)

Fusion research at Culham site

International Nuclear Information System (INIS)

Tolonen, P.; Toppila, T.

1998-01-01

One of the many targets on the Finnish Nuclear Society (ATS) excursion to England was the Culham fusion research site. The site has divided into two parts. One of them is UKAEA Fusion with small scale fusion reactors and 200 employees. UKAEA has 3 fusion reactors at Culham site. One of is the START (Small Tight Aspect Ratio Tokamak) which was operational since 1991 but is today already out of operation. UKAEA has been operating a JET-like tokamak fusion reactor COMPASS-D since 1989. The latest of three reactors is MAST (Mega Amp Spherical Tokamak), which is still under construction. The first plasma will take place in the end of 1998. Another part of Culham site is JET (Joint European Torus), an all-European fusion undertaking with 350 employees. 150 of them are from various European countries and the rest 200 are employed by UKAEA. JET is the biggest fusion reactor ever and it represents the latest step in world wide fusion programme. In October 1997 JET achieved a world record in fusion power and energy. JET produced 16,1 MW power for 1 s and totally 21,7 MJ energy. This is the closest attempt to achieve break-even conditions. The next step in world wide fusion programme will be international ITER-reactor. This undertaking has some financial problems, since United States has taken distance to magnetic fusion research and moved closer to inertial fusion with funding of US Department of Defence. The planned reactor, however, is physically twice as big as JET. The step after this phase will be DEMO, which is purposed to produce fusion energy. According to our hosts in Culham this phase is 40 years ahead. (author)

A future for nuclear sites beyond their service life. Nuclear site value development

International Nuclear Information System (INIS)

2008-01-01

As the nuclear industry moves into a new development phase, many facilities built in the fifties and sixties are reaching the end of their service life. Dismantling them and rehabilitating the sites on which they stand is a major industrial challenge which will give rise to a number of new projects. AREVA has more than 20 years' experience in these highly technical fields. As more and more sites reach the end of their service life, AREVA considers nuclear site value development as a fully-fledged industrial activity. The group's competencies in this field have been grouped together to form a dedicated entity: the Nuclear Site Value Development Business Unit, created in 2008. Several billion euros are invested in site value development projects which are far-reaching and complex, and often last for several decades. Long before work actually begins, lengthy studies and preparations are required to schedule operations, select the techniques to be used and optimize costs and deadlines. The Nuclear Site Value Development BU is currently working on four major projects involving its own facilities and those of the CEA: - La Hague: dismantling of the first generation of used fuel recycling facilities. Between 1966 and 1998, almost 5,000 tons of used fuel from graphite-moderated gas-cooled reactors, 4,500 tons of light water reactor fuel, as well as fuel from fast reactors and research reactors, were treated at UP2 400, the very first industrial recycling plant on the La Hague site. - Marcoule: first-time dismantling of a recycling plant. 1,000 rooms to be cleaned up, 30,000 tons of waste to be treated, 30 years of work. - Cadarache: first-time dismantling of a Mox fuel fabrication plant. The Cadarache plant was commissioned in 1962 to fabricate fuel for fast reactors; this was followed by MOX fuel for light water reactors, an activity which continued until the plant was shut down in 2003. - Annecy and Veurey: giving a new lease of life to former industrial sites in built

Analysis of coolability of the control rods of a Savannah River Site production reactor with loss of normal forced convection cooling

International Nuclear Information System (INIS)

Easterling, T.C.; Hightower, N.T.; Smith, D.C.; Amos, C.N.

1992-01-01

An analytical study of the coolability of the control rods in the Savannah River Site (SRS) K-Production Reactor under conditions of loss of normal forced convection cooling has been performed. The study was performed as part of the overall safety analysis of the reactor supporting its restart. The analysis addresses the buoyancy-driven flow over the control rods that occurs when forced cooling is lost, and the limit of critical heat flux that sets the acceptance criteria for the study. The objective of the study is to demonstrate that the control rods will remain cooled at powers representative of those anticipated for restart of the reactor. The study accomplishes this objective with a very tractable simplified analysis for the modest restart power. In addition, a best-estimate calculation is performed, and the results are compared to results from sub-scale scoping experiments. 5 refs

Training courses on neutron detection systems on the ISIS research reactor: on-site and through internet training

Energy Technology Data Exchange (ETDEWEB)

Lescop, B.; Badeau, G.; Ivanovic, S.; Foulon, F. [National Institute for Nuclear science and Technology French Atomic Energy and Alternative Energies Commission (CEA), Saclay Research Center, 91191 Gif-sur-Yvette (France)

2015-07-01

Today, ISIS research reactor is an essential tool for Education and Training programs organized by the National Institute for Nuclear Science and Technology (INSTN) from CEA. In the field of nuclear instrumentation, the INSTN offers both, theoretical courses and training courses on the use of neutron detection systems taking advantage of the ISIS research reactor for the supply of a wide range of neutron fluxes. This paper describes the content of the training carried out on the use of neutron detectors and detection systems, on-site or remote. The ISIS reactor is a 700 kW open core pool type reactor. The facility is very flexible since neutron detectors can be inserted into the core or its vicinity, and be used at different levels of power according to the needs of the course. Neutron fluxes, typically ranging from 1 to 10{sup 12} n/cm{sup 2}.s, can be obtained for the characterisation of the neutron detectors and detection systems. For the monitoring of the neutron density at low level of power, the Instrumentation and Control (I and C) system of the reactor is equipped with two detection systems, named BN1 and BN2. Each way contains a fission chamber, type CFUL01, connected to an electronic system type SIREX.The system works in pulse mode and exhibits two outputs: the counting rate and the doubling time. For the high level of power, the I and C is equipped with two detection systems HN1 and HN2.Each way contain a boron ionization chamber (type CC52) connected to an electronics system type SIREX. The system works in current mode and has two outputs: the current and the doubling time. For each mode, the trainees can observe and measure the signal at the different stages of the electronic system, with an oscilloscope. They can understand the role of each component of the detection system: detector, cable and each electronic block. The limitation of the detection modes and their operating range can be established from the measured signal. The trainees can also

Training courses on neutron detection systems on the ISIS research reactor: on-site and through internet training

International Nuclear Information System (INIS)

Lescop, B.; Badeau, G.; Ivanovic, S.; Foulon, F.

2015-01-01

Today, ISIS research reactor is an essential tool for Education and Training programs organized by the National Institute for Nuclear Science and Technology (INSTN) from CEA. In the field of nuclear instrumentation, the INSTN offers both, theoretical courses and training courses on the use of neutron detection systems taking advantage of the ISIS research reactor for the supply of a wide range of neutron fluxes. This paper describes the content of the training carried out on the use of neutron detectors and detection systems, on-site or remote. The ISIS reactor is a 700 kW open core pool type reactor. The facility is very flexible since neutron detectors can be inserted into the core or its vicinity, and be used at different levels of power according to the needs of the course. Neutron fluxes, typically ranging from 1 to 10 12 n/cm 2 .s, can be obtained for the characterisation of the neutron detectors and detection systems. For the monitoring of the neutron density at low level of power, the Instrumentation and Control (I and C) system of the reactor is equipped with two detection systems, named BN1 and BN2. Each way contains a fission chamber, type CFUL01, connected to an electronic system type SIREX.The system works in pulse mode and exhibits two outputs: the counting rate and the doubling time. For the high level of power, the I and C is equipped with two detection systems HN1 and HN2.Each way contain a boron ionization chamber (type CC52) connected to an electronics system type SIREX. The system works in current mode and has two outputs: the current and the doubling time. For each mode, the trainees can observe and measure the signal at the different stages of the electronic system, with an oscilloscope. They can understand the role of each component of the detection system: detector, cable and each electronic block. The limitation of the detection modes and their operating range can be established from the measured signal. The trainees can also modify the

Off-site protective action selection for nuclear reactor accidents

International Nuclear Information System (INIS)

Weerakkody, S.D.

1986-01-01

A computer program based upon a model using a rational theoretical basis was developed to select appropriate off-site protective actions during nuclear reactor accidents. The special features of this program include (a) introduction of a precursor concept that uses the history of the accident progression to determine the spectrum of potential accident scenarios and estimates of the likelihoods of each accident scenario; (b) use of statistical decision theory and the concept of entropy of a spectrum to select the appropriate protective actions using either the minimax principle or the Bayes action method; and (c) introduction of methods to quantify evacuation travel risks. In order to illustrate the usefulness of the computer program, it was applied at three stages of the Three Mile Island accident scenario. Quantified non-radiological risks of evaluation have been used to establish dose thresholds below which evacuations are not justified. Using the Poisson analysis for evacuation risks and the absolute L-L BEIR model for radiation risk suggests 330 mrems as a reasonable value for this threshold. The usefulness of the program in developing a technical basis to select the size of the plume exposure pathway emergency planning zone (EPZ) is discussed. Quantified evacuation risks, cost, and the current rationale upon which the EPZ is based, justify an EPZ between 5-10 miles for WASH-1400 source-terms

Significance assessment of small-medium sized reactors

Energy Technology Data Exchange (ETDEWEB)

Kanno, Minoru [Japan Atomic Power Co., Research and Development Dept., Tokyo (Japan)

2002-12-01

Preliminary assessment for deployment of small-medium sized reactor (S and M reactor) as a future option has been conducted at the JAPCO (Japan Atomic Power Company) under the cooperation with the CRIERI (Central Research Institute of Electric Power Industry). Significance of the S and M reactor introduction is listed as follows; lower investment cost, possible siting near demand side, enlarged freedom of siting, shorter transmission line, good compatibility with slow increase of demand and plain explanation of safety using simpler system such as integral type vessel without piping, natural convection core cooling and passive safety system. The deployment of simpler plant system, modular shop fabrication, ship-shell structured building and longer operation period can assure economics comparable with that of a large sized reactor, coping with scale-demerit. Also the S and M reactor is preferable in size for the nuclear heat utilization such as hydrogen production. (T. Tanaka)

Windscale advanced gas-cooled reactor (WAGR) decommissioning project overview

International Nuclear Information System (INIS)

Pattinson, A.

2003-01-01

The current BNFL reactor decommissioning projects are presented. The projects concern power reactor sites at Berkely, Trawsfynydd, Hunterstone, Bradwell, Hinkley Point; UKAEA Windscale Pile 1; Research reactors within UK Scottish Universities at East Kilbride and ICI (both complete); WAGR. The BNFL environmental role include contract management; effective dismantling strategy development; implementation and operation; sentencing, encapsulation and transportation of waste. In addition for the own sites it includes strategy development; baseline decommissioning planning; site management and regulator interface. The project objectives for the Windscale Advanced Gas-Cooled Reactor (WAGR) are 1) Safe and efficient decommissioning; 2) Building of good relationships with customer; 3) Completion of reactor decommissioning in 2005. The completed WAGR decommissioning campaigns are: Operational Waste; Hot Box; Loop Tubes; Neutron Shield; Graphite Core and Restrain System; Thermal Shield. The current campaign is Lower Structures and the remaining are: Pressure vessel and Insulation; Thermal Columns and Outer Vault Membrane. An overview of each campaign is presented

Testing of research reactor fuel in the high flux reactor (Petten)

International Nuclear Information System (INIS)

Guidez, J.; Markgraf, J.W.; Sordon, G.; Wijtsma, F.J.; Thijssen, P.J.M.; Hendriks, J.A.

1999-01-01

The two types of fuel most frequently used by the main research reactors are metallic: highly enriched uranium (>90%) and silicide low enriched uranium ( 3 . However, a need exists for research on new reactor fuel. This would permit some plants to convert without losses in flux or in cycle length and would allow new reactor projects to achieve higher possibilities especially in fluxes. In these cases research is made either on silicide with higher density, or on other types of fuel (UMo, etc.). In all cases when new fuel is proposed, there is a need, for safety reasons, to test it, especially regarding the mechanical evolution due to burn-up (swelling, etc.). Initially, such tests are often made with separate plates, but lately, using entire elements. Destructive examinations are often necessary. For this type of test, the High Flux Reactor, located in Petten (The Netherlands) has many specific advantages: a large core, providing a variety of interesting positions with high fluence rate; a downward coolant flow simplifies the engineering of the device; there exists easy access with all handling possibilities to the hot-cells; the high number of operating days (>280 days/year), together with the high flux, gives a possibility to reach quickly the high burn-up needs; an experienced engineering department capable of translating specific requirements to tailor-made experimental devices; a well equipped hot-cell laboratory on site to perform all necessary measurements (swelling, γ-scanning, profilometry) and all destructive examinations. In conclusion, the HFR reactor readily permits experimental research on specific fuels used for research reactors with all the necessary facilities on the Petten site. (author)

Sites for locations of nuclear reactors

International Nuclear Information System (INIS)

Balcazar, M.; Huerta, M.; Lopez, A.

2014-10-01

A restriction on sites of nuclear energy is the history of seismic activity, in its magnitude (Richter) and intensity (Mercalli). This article delimits the areas of greatest magnitude and national seismic intensity, with restrictions of ground acceleration; the supplement areas with a low magnitude of seismic activity are shown. Potential sites for the location of these sites are introduced into a geographic information system. The set of geo-referenced data contains the location of the active volcanic manifestations; the historical record of earthquake epicenters, magnitudes and intensities; major geological faults; surface hydrology and water bodies; location of population density; protected areas; contour lines; the rock type or geology. The geographic information system allows entering normative criteria and environmental restrictions that correlate with geo-referenced data described above, forms both probable and exclusion areas for the installation of nuclear sites. (Author)

Savannah River Site reactor hardware design modification study

International Nuclear Information System (INIS)

Fisher, J.E.

1990-03-01

A study was undertaken to assess the merits of proposed design modifications to the SRS reactors. The evaluation was based on the responses calculated by the RELAP5 systems code to double-ended guillotine break loss-of-coolant-accidents (DEGB LOCAs). The three concepts evaluated were (a) elevated plenum inlet piping with a guard vessel and clamshell enclosures, (b) closure of both rotovalves in the affected loop, and (c) closure of the pump suction valve in the affected loop. Each concept included a fast reactor shutdown (to 65% power in 100 ms) and a 2-s ac pump trip. For the elevated piping design, system recovery was predicted for breaks in the plenum inlet or pump suction piping; response to the pump discharge break location did not show improvement compared to the present system configuration. The rotovalve closure design improved system response to plenum inlet or pump discharge breaks; recovery was not predicted for pump suction breaks. The pump suction valve closure design demonstrated system recovery for all break locations downstream of the valve. A combination of features is recommended to ensure liquid inventory recovery for all break locations. The elevated piping design performance during pump discharge breaks would be improved with addition of a dc pump trip in the affected loop. Valve closure design performance for a break location in the short section of piping between the reactor concrete shield and the pump suction valve would benefit from the clamshell enclosing that section of piping. 12 refs., 10 figs., 2 tabs

Simulation and control of the site-dependent neutron density in a nuclear reactor

International Nuclear Information System (INIS)

Stark, K.

1974-01-01

The present work deals with the simulation and control of a pressurized-water reactor such as is used in nuclear power plants today. In the first part of the work, the mathematical model equations of the reactor are set up. They take into consideration the local distribution of the various reactor parameters as far as seems necessary for further investigations. Taking the given approximations, the mathematical model is locally one-dimensional; it is valid for the period of time in which a power control of the reactor must work. The model equations set up are calculated on an analog/hybride computer according to the modal simulation method in true time. The method is distinguished in the present problem here through good convergence and enables the observation of the simulation results as a stationary picture on an oscillograph screen. For this reason, a simulation of this type seems particularly suitable for the training of operational personnel. The aim of the second part of the work is the development of a simple control concept which enables the control of the total power of the reactor as well as of the distribution of the power density in the reactor core. The fundamentals of the control design are the non-linear system equations of the nuclear reactor. The developed control is based on the controlling of eigenfunctions; it controls the total power of the reactor as well as the distribution of the power density in the reactor core where a uniform burn-up of the nuclear fuel is seen to. Part-absorbing control rods amongst others are used as actuators like they are already used in that type of reactors. (orig./LH) [de

Nuclear power: Siting and safety

International Nuclear Information System (INIS)

Openshaw, S.

1986-01-01

By 2030, half, or even two-thirds, of all electricity may be generated by nuclear power. Major reactor accidents are still expected to be rare occurrences, but nuclear safety is largely a matter of faith. Terrorist attacks, sabotage, and human error could cause a significant accident. Reactor siting can offer an additional, design-independent margin of safety. Remote geographical sites for new plants would minimize health risks, protect the industry from negative changes in public opinion concerning nuclear energy, and improve long-term public acceptance of nuclear power. U.K. siting practices usually do not consider the contribution to safety that could be obtained from remote sites. This book discusses the present trends of siting policies of nuclear power and their design-independent margin of safety

Research reactor developments in Australia

International Nuclear Information System (INIS)

Godfrey, Robert

1998-01-01

The Australian Nuclear Science and Technology Organization (ANSTO) operates the 10 MW research reactor, HIFAR, at the Lucas Heights site approximately 30 kilometres south of Sydney. Although recent reviews and inspections have confirmed that HIFAR operates safely by an adequate margin and has minimal impact, it was concluded that the reactor design and age places limitations on its operation and utilization, and that HIFAR is approaching the end of its economic life. In September 1997, a decision was made by the Australian Government to found ANSTO for the construction of a replacement research on the existing Lucas Heights site, subject to the requisite environmental assessment process. A draft EIS has been prepared and is currently undergoing public review. A design specification is in preparation, and a research reactor vendor pre-qualification process has been initiated. Spent fuel shipments have been made to Dounreay and to the Savannah River Site, and discussions are continuing regarding the disposition of the existing spent fuel and that arising form HIFAR's remaining operation. (author)

Operational power reactor health physics

International Nuclear Information System (INIS)

Watson, B.A.

1987-01-01

Operational Health Physics can be comprised of a multitude of organizations, both corporate and at the plant sites. The following discussion centers around Baltimore Gas and Electric's (BG and E) Calvert Cliffs Nuclear Power Plant, located in Lusby, Maryland. Calvert Cliffs is a twin Combustion Engineering 825 MWe pressurized water reactor site with Unit I having a General electric turbine-generator and Unit II having a Westinghouse turbine-generator. Having just completed each Unit's ten-year Inservice Inspection and Refueling Outge, a total of 20 reactor years operating health physics experience have been accumulated at Calvert Cliffs. Because BG and E has only one nuclear site most health physics functions are performed at the plant site. This is also true for the other BG and E nuclear related organizations, such as Engineering and Quality Assurance. Utilities with multiple plant sites have corporate health physics entity usually providing oversight to the various plant programs

Radiological walkover survey at the site of the world's first nuclear reactor using the NAVSTAR global positioning system

International Nuclear Information System (INIS)

Sims, J.; Barry, C.; Efird, C.

1994-01-01

A radiological walkover survey was conducted by Bechtel National, Inc. (BNI) in the spring of 1994 at Site A, the site of the world's first nuclear reactor pilot plant facility. The objective of this survey was to provide comprehensive information regarding surface radiation levels to support identification and documentation of unknown contaminated areas and selection of future sample locations, and provide information for health and safety coverage during field investigations. The technique used represented a new application integrating the radiation measuring instrumentation with the global positioning system (GPS) in real-time differential mode. The integrated mapping and radiation survey system (MARSS) developed by J.S. Bland Associates, Inc. (JSB) simultaneously recorded direct radiation, exposure rate, and position data. Site A is in the Palos Forest Preserve, about 20 miles southwest of downtown Chicago, Illinois. The topography of the site is relatively flat (usually less than 5 % grade), with a maximum grade of 10%. Prior to the survey, the site was staked on 100-ft. centers and roughly 75% of the site was cleared of dense vegetation including trees less than 6 in. in diameter. The survey covered approximately 2 acres each day, including background determinations, source checks, calibrations, and downloading of integrated position data and radiological measurements

Reactor Safety Commission Code of Practice for Pressurized Water Reactors

International Nuclear Information System (INIS)

1990-01-01

The Reactor Safety Commission of the Federal German Republic has summarized in the form of Official Guidelines the safety requirements which, in the Commission's view, have to be met in the design, construction and operation of a nuclear power station equipped with a pressurized water reactor. The Third Edition of the RSK Guidelines for pressurized water reactors dated 14.10.81. is a revised and expanded version of the Second Edition dated 24.1.79. The Reactor Safety Commission will with effect from October 1981 use these Guidelines in consultations on the siting of and safety concept for the installation approval of future pressurized water reactors and will assess these nuclear power stations during their erection in the light of these Guidelines. They have not however been immediately conceived for the adaptation of existing nuclear power stations, whether under construction or in operation. The scope of application of these Guidelines to such nuclear power stations will have to be examined for each individual case. The main aim of the Guidelines is to simplify the consultation process within the reactor Safety Commission and to provide early advice on the safety requirements considered necessary by the Commission. (author)

Results of assembly test of HTTR reactor internals

International Nuclear Information System (INIS)

Maruyama, S.; Saikusa, A.; Shiozawa, S.; Tsuji, N.; Miki, T.

1996-01-01

The assembly test of the HTTR actual reactor internals had been carried out at the works, prior to their installation in the actual reactor pressure vessel(RPV) at the construction site. The assembly test consists of several items such as examining fabricating precision of each component and alignment of piled-up structures, measuring circumferential coolant velocity profile in the passage between the simulated RPV and the reactor internals as well as under the support plates, measuring by-pass flow rate through gaps between the reactor internals, and measuring the binding force of the core restraint mechanism. Results of the test showed good performance of the HTTR reactor internals. Installation of the reactor internals in the actual RPV was started at the construction site of HTTR in April, 1995. In the installation process, main items of the assembly test at the works were repeated to investigate the reproducibility of installation. (author). 5 refs, 11 figs

Reactor operation environmental information document

Energy Technology Data Exchange (ETDEWEB)

Haselow, J.S.; Price, V.; Stephenson, D.E.; Bledsoe, H.W.; Looney, B.B.

1989-12-01

The Savannah River Site (SRS) produces nuclear materials, primarily plutonium and tritium, to meet the requirements of the Department of Defense. These products have been formed in nuclear reactors that were built during 1950--1955 at the SRS. K, L, and P reactors are three of five reactors that have been used in the past to produce the nuclear materials. All three of these reactors discontinued operation in 1988. Currently, intense efforts are being extended to prepare these three reactors for restart in a manner that protects human health and the environment. To document that restarting the reactors will have minimal impacts to human health and the environment, a three-volume Reactor Operations Environmental Impact Document has been prepared. The document focuses on the impacts of restarting the K, L, and P reactors on both the SRS and surrounding areas. This volume discusses the geology, seismology, and subsurface hydrology. 195 refs., 101 figs., 16 tabs.

Technical concept for a test of geologic storage of spent reactor fuel in the climax granite, Nevada Test Site

International Nuclear Information System (INIS)

Ramspott, L.D.; Ballou, L.B.; Carlson, R.C.; Montan, D.N.; Butkovich, T.R.; Duncan, J.E.; Patrick, W.C.; Wilder, D.G.; Brough, W.G.; Mayr, M.C.

1979-01-01

We plan to emplace spent fuel assemblies from an operating commercial nuclear reactor in the Climax granite at the US Department of Energy's Nevada Test Site. In this generic test, 11 canisters of spent fuel will be emplaced with 6 electrical simulator canisters in a storage drift 420 m below in surface and their effects compared. Two adjacent drifts will contain electrical heaters, operated to simulate the temperature-stress-displacement fields of a large repository. We describe the test objectives, the technical issues, the site, the preoperational measurement program, thermal and mechanical response calculations, the characteristics of the spent fuel, the field instrumentation and data-acquisition systems, and the system for handling the spent fuel

The current status of nuclear research reactor in Thailand

Energy Technology Data Exchange (ETDEWEB)

Sittichai, C; Kanyukt, R; Pongpat, P [Office of Atomic Energy for Peace, Bangkok (Thailand)

1998-10-01

Since 1962, the Thai Research Reactor has been serving for various kinds of activities i.e. the production of radioisotopes for medical uses and research and development on nuclear science and technology, for more than three decades. The existing reactor site should be abandoned and relocated to the new suitable site, according to Thai cabinet`s resolution on the 27 December 1989. The decommissioning project for the present reactor as well as the establishment of new nuclear research center were planned. This paper discussed the OAEP concept for the decommissioning programme and the general description of the new research reactor and some related information were also reported. (author)

Decommissioning a nuclear reactor

International Nuclear Information System (INIS)

Montoya, G.M.

1991-01-01

The process of decommissioning a facility such as a nuclear reactor or reprocessing plant presents many waste management options and concerns. Waste minimization is a primary consideration, along with protecting a personnel and the environment. Waste management is complicated in that both radioactive and chemical hazardous wastes must be dealt with. This paper presents the general decommissioning approach of a recent project at Los Alamos. Included are the following technical objectives: site characterization work that provided a thorough physical, chemical, and radiological assessment of the contamination at the site; demonstration of the safe and cost-effective dismantlement of a highly contaminated and activated nuclear-fuelded reactor; and techniques used in minimizing radioactive and hazardous waste. 12 figs

The integral fast reactor

International Nuclear Information System (INIS)

Till, C.E.

1987-01-01

On April 3rd, 1986, two dramatic demonstrations of the inherent capability of sodium-cooled fast reactors to survive unprotected loss of cooling accidents were carried out on the experimental sodium-cooled power reactor, EBR-II, on the Idaho site of Argonne National Laboratory. Transients potentially of the most serious kind, one an unprotected loss of flow, the other an unprotected loss of heat sink, both initiated from full power. In both cases the reactor quietly shut itself down, without damage of any kind. These tests were a part of the on-going development program at Argonne to develop an advanced reactor with significant new inherent safety characteristics. Called the Integral Fast Reactor, or IFR, the basic thrust is to develop everything that is needed for a complete nuclear power system - reactor, closed fuel cycle, and waste processing - as a single optimized entity, and, for simplicity in concept, as an integral part of a single plant. The particular selection of reactor materials emphasizes inherent safety characteristics and also makes possible a simplified closed fuel cycle and waste process improvements

Replacement research reactor for Australia

International Nuclear Information System (INIS)

Miller, Ross

1998-01-01

In 1992, the Australian Government commissioned a review into the need for a replacement research reactor. That review concluded that in about years, if certain conditions were met, the Government could make a decision in favour of a replacement reactor. A major milestone was achieved when, on 3 September 1997, the Australian Government announced the construction of a replacement research reactor at the site of Australia's existing research reactor HIFAR, subject to the satisfactory outcome of an environmental assessment process. The reactor will be have the dual purpose of providing a first class facility for neutron beam research as well as providing irradiation facilities for both medical isotope production and commercial irradiations. The project is scheduled for completion before the end of 2005. (author)

Natural fission reactors - the Oklo phenomenon

International Nuclear Information System (INIS)

Anon.

1989-01-01

Overview describes the discovery of the site, location of the reactors and site geology and discusses the permanence of fission products, nuclear reaction control mechanisms and trace concentrations of elements that act as poisons. (Author)

Siting nuclear power plants

International Nuclear Information System (INIS)

Yellin, J.; Joskow, P.L.

1980-01-01

The first edition of this journal is devoted to the policies and problems of siting nuclear power plants and the question of how far commercial reactors should be placed from urban areas. The article is divided into four major siting issues: policies, risk evaluation, accident consequences, and economic and physical constraints. One concern is how to treat currently operating reactors and those under construction that were established under less-stringent criteria if siting is to be used as a way to limit the consequences of accidents. Mehanical cost-benefit analyses are not as appropriate as the systematic use of empirical observations in assessing the values involved. Stricter siting rules are justified because (1) opposition because of safety is growing: (2) remote siting will make the industry more stable; (3) the conflict is eliminated between regulatory policies and the probability basis for nuclear insurance; and (4) joint ownership of utilities and power-pooling are increasing. 227 references, 7 tables

Reactor plant for Belene NPP completion

International Nuclear Information System (INIS)

Dragunov, Yu. G.; Ryzhov, S. B.; Ermakov, D. N.; Repin, A. I.

2004-01-01

Construction of 'Belene' NPP was started at the end of 80-ties using project U-87 with V-320 reactor plant, general designer of this plant is OKB 'Gidropress'. At the beginning of 90-ties, on completing the considerable number of deliveries and performance of civil engineering work at the site the NPP construction was suspended. Nowadays, considering the state of affairs at the site and the work performed by Bulgarian Party on preservation of the equipment delivered, the most perspective is supposed to be implementation of the following versions in completing 'Belene' NPP: for completion of Unit 1 - reactor plant VVER-1000 on the basis of V-320 reactor with the maximum use of the delivered equipment (V-320M) having the extended service life and safety improvement; for Unit 2 - advanced reactor plant VVER-1000. For the upgraded reactor plant V-230M the basic solutions and characteristics are presented, as well as the calculated justification of strength and safety analyses, design of the reactor core and fuel cycle, instrumentation and control systems, application of the 'leak-before break' in the project and implementation of safety measures. For the modernised reactor plant V-392M the main characteristics and basic changes are presented, concerning reactor pressure vessel, steam generator, reactor coolant pump set. Design of NPP with the modernized reactor plant V-320M meets the up-to-date requirements and can be licensed for completion and operation. In the design of NPP with the advanced reactor plant the basic solutions and the equipment are used that are similar to those used in standard reactor plant V-320 and new one with VVER-1000 under construction and completion in Russia, and abroad. Compliance of reactor design with the up-to-date international requirements, considering the extended service life of the main equipment, shows its rather high potential for implementation during completion of 'Belene' NPP

New Reactor Siting in Finland, Hanhikivi Site in Pyhaejoki - STUK preliminary safety assessment

International Nuclear Information System (INIS)

Nevalainen, Janne

2013-01-01

STUK has performed a preliminary assessment of the Decision-in-Principle on the Fennovoima application. A variety of factors must be considered in the selection of a site, including effects of the site on the plant design and the effects of the plant on the site environment. These include external hazards, both natural and human-induced. Since this is a new site, an extensive siting process is followed, that can include an EIA. A site survey is performed to identify candidate sites, after investigating a large region and rejecting unsuitable sites. The remaining sites are then screened and compared on the basis of safety and other considerations to select one or more preferred sites. Natural hazards include geology, seismology, hydrology and meteorology. Offshore ice will be a particular hazard for this plant, since the site is on average only 1.5 m above sea level. The design basis earthquake corresponds to a return frequency of 100,000 years, with 50 % confidence. The existing sites in southern Finland used a design peak ground acceleration of 0.1 g with the ground response spectrum maximum at 10 Hz. The candidate sites in northern Finland will require a peak ground acceleration of 0.2 g with the ground response spectrum maximum at 25 Hz

Chernobyl reactor accident

International Nuclear Information System (INIS)

Malinauskas, A.P.; Buchanan, J.R.; Lorenz, R.A.; Yamashita, T.

1986-01-01

On April 26, 1986, an explosion occurred at the newest of four operating nuclear reactors at the Chernobyl site in the USSR. The accident initiated an international technical exchange of almost unprecedented magnitude; this exchange was climaxed with a meeting at the International Atomic Energy Agency in Vienna during the week of August 25, 1986. The meeting was attended by more than 540 official representatives from 51 countries and 20 international organizations. Information gleaned from that technical exchange is presented in this report. A description of the Chernobyl reactor, which differs significantly from commercial US reactors, is presented, the accident scenario advanced by the Russian delegation is discussed, and observations that have been made concerning fission product release are described

Study on the decommissioning of research reactor

Energy Technology Data Exchange (ETDEWEB)

Suh, Doo Hwan; Jun, Kwan Sik; Choi, Yoon Dong; Lee, Tae Yung; Kwon, Sang Woon; Lee, Jong Il [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1995-01-01

Currently, KAERI operates TRIGA Mark-II and TRIGA Mark-III research reactors as a general purpose research and training facility. As these are, however, situated at Seoul office site of KAERI which is scheduled to be transferred to KEPCO as well as 30 MW HANARO research reactor which is expected to reach the first criticality in 1995 is under construction at head site of KAERI, decommissioning of TRIGA reactors has become an important topic. The objective of this study is to prepare and present TRIGA facility decontamination and decommissioning plan. Estimation of the radioactive inventory in TRIGA research reactor was carried out by the use of computational method. In addition, summarized in particular were the methodologies associated with decontamination, segmenting processes for activated metallic components, disposition of wastes. Particular consideration in this study was focused available technology applicable to decommissioning of TRIGA research reactor. State-of-the-art summaries of the available technology for decommissioning presented here will serve a useful document for preparations for decommissioning in the future. 6 figs, 41 tabs, 30 refs. (Author).

The molten salt reactor adventure

International Nuclear Information System (INIS)

MacPherson, H.G.

1985-01-01

A personal history of the development of molten salt reactors in the United States is presented. The initial goal was an aircraft propulsion reactor, and a molten fluoride-fueled Aircraft Reactor Experiment was operated at Oak Ridge National Laboratory in 1954. In 1956, the objective shifted to civilian nuclear power, and reactor concepts were developed using a circulating UF 4 -ThF 4 fuel, graphite moderator, and Hastelloy N pressure boundary. The program culminated in the successful operation of the Molten Salt Reactor Experiment in 1965 to 1969. By then the Atomic Energy Commission's goals had shifted to breeder development; the molten salt program supported on-site reprocessing development and study of various reactor arrangements that had potential to breed. Some commercial and foreign interest contributed to the program which, however, was terminated by the government in 1976. The current status of the technology and prospects for revived interest are summarized

Nuclear power reactor technology

International Nuclear Information System (INIS)

1978-09-01

Risoe National Laboratory was established more than twenty years ago with research and development of nuclear reactor technology as its main objective. The Laboratory has by now accumulated many years of experience in a number of areas vital to nuclear reactor technology. The work and experience of, and services offered by the Laboratory within the following fields are described: Health physics site supervision; Treatment of low and medium level radioactive waste; Core performance evaluation; Transient analysis; Accident analysis; Fuel management; Fuel element design, fabrication and performance evaluation; Non-destructive testing of nuclear fuel; Theoretical and experimental structural analysis; Reliability analysis; Site evaluation. Environmental risk and hazard calculation; Review and analysis of safety documentation. Risoe has already given much assistance to the authorities, utilities and industries in such fields, carrying out work on both light and heavy water reactors. The Laboratory now offers its services to others as a consultant, in education and training of staff, in planning, in qualitative and quantitative analysis, and for the development and specification of fabrication techniques. (author)

The market for HTGR type reactors

International Nuclear Information System (INIS)

Roehler, E.

1986-01-01

High-temperature-reactors with pebble-bed-reactor cores as a progressive reactor line, have been developed by BBC/HRB the Federal Republic of Germany over a period of 27 years and will soon be mature to be introduced to the market. They represent an important innovation in the field of reactor engineering. Due to its high degree of applicability on the power and heat market and its high flexibility regarding the site and fuel cycle the HTR is extremely suitable for providing energy to consumers, especially in countries using nuclear energy supply for the first time. (orig.) [de

The integral fast reactor

International Nuclear Information System (INIS)

Till, C.E.

1987-01-01

On April 3rd, 1986, two demonstrations of the inherent capability of sodium-cooled fast reactors to survive unprotected loss of cooling accidents were carried out on the experimental sodium-cooled power reactor, EBR-II, on the Idaho site of Argonne National Laboratory. Transients potentially of the most serious kind, one an unprotected loss of flow, the other an unprotected loss of heat sink, both initiated from full power. In both cases the reactor quietly shut itself down, without damage of any kind. These tests were a part of the on-going development program at Argonne to develop an advanced reactor with significant new inherent safety characteristics. Called the integral fast reactor, or IFR, the basic thrust is to develop everything that is needed for a complete nuclear power system - reactor, closed fuel cycle, and waste processing - as a single optimized entity, and, for simplicity in concept, as an integral part of a single plant. The particular selection of reactor materials emphasizes inherent safety characteristics also makes possible a simplified close fuel cycle and waste process improvements. The paper describes the IFR concept, the inherent safety, tests, and status of IFR development today

The secure heating reactor

International Nuclear Information System (INIS)

Pind, C.

1987-01-01

The SECURE heating reactor was designed by ASEA-ATOM as a realistic alternative for district heating in urban areas and for supplying heat to process industries. SECURE has unique safety characteristics, that are based on fundamental laws of physics. The safety does not depend on active components or operator intervention for shutdown and cooling of the reactor. The inherent safety characteristics of the plant cannot be affected by operator errors. Due to its very low environment impact, it can be sited close to heat consumers. The SECURE heating reactor has been shown to be competitive in comparison with other alternatives for heating Helsinki and Seoul. The SECURE heating reactor forms a basis for the power-producing SECURE-P reactor known as PIUS (Process Inherent Ultimate Safety), which is based on the same inherent safety principles. The thermohydraulic function and transient response have been demonstrated in a large electrically heated loop at the ASEA-ATOM laboratories

Evaluation of Potential Locations for Siting Small Modular Reactors near Federal Energy Clusters to Support Federal Clean Energy Goals

Energy Technology Data Exchange (ETDEWEB)

Belles, Randy J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Omitaomu, Olufemi A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2014-09-01

Geographic information systems (GIS) technology was applied to analyze federal energy demand across the contiguous US. Several federal energy clusters were previously identified, including Hampton Roads, Virginia, which was subsequently studied in detail. This study provides an analysis of three additional diverse federal energy clusters. The analysis shows that there are potential sites in various federal energy clusters that could be evaluated further for placement of an integral pressurized-water reactor (iPWR) to support meeting federal clean energy goals.

Technical guidance for siting criteria development

International Nuclear Information System (INIS)

Aldrich, D.C.; Sprung, J.L.; Alpert, D.J.

1982-12-01

Technical guidance to support the formulation and comparison of possible siting criteria for nuclear power plants has been developed in four areas: (1) consequences of hypothetical severe nuclear-power-plant accidents, (2) characteristics of population distributions about current reactor sites, (3) site availability within the continental United States, and (4) socioeconomic impacts of reactor siting. The impact on consequences of source-term magnitude, meteorology, population distribution, and emergency response have been analyzed. Population distributions about current sites were analyzed to identify statistical characteristics, time trends, and regional differences. A site-availability data bank was constructed for the continential United States. The data bank contains information about population densities, seismicity, topography, water availability, and land-use restrictions. Finally, the socioeconomic impacts of rural-industrialization projects, energy boomtowns, and nuclear power plants were examined to determine their nature, magnitude, and dependence on site demography and remoteness

Technical guidance for siting criteria development

Energy Technology Data Exchange (ETDEWEB)

Aldrich, D.C.; Sprung, J.L.; Alpert, D.J.; Diegert, K.; Ostmeyer, R.M.; Ritchie, L.T.; Strip, D.R.; Johnson, J.D.; Hansen, K.; Robinson, J.

1982-12-01

Technical guidance to support the formulation and comparison of possible siting criteria for nuclear power plants has been developed in four areas: (1) consequences of hypothetical severe nuclear-power-plant accidents, (2) characteristics of population distributions about current reactor sites, (3) site availability within the continental United States, and (4) socioeconomic impacts of reactor siting. The impact on consequences of source-term magnitude, meteorology, population distribution, and emergency response have been analyzed. Population distributions about current sites were analyzed to identify statistical characteristics, time trends, and regional differences. A site-availability data bank was constructed for the continential United States. The data bank contains information about population densities, seismicity, topography, water availability, and land-use restrictions. Finally, the socioeconomic impacts of rural-industrialization projects, energy boomtowns, and nuclear power plants were examined to determine their nature, magnitude, and dependence on site demography and remoteness.

Technical concept for test of geologic storage of spent reactor fuel in the Climax granite, Nevada Test Site

International Nuclear Information System (INIS)

Ramspott, L.D.; Ballou, L.B.; Carlson, R.C.; Montan, D.N.; Butkovich, T.R.; Duncan, J.E.; Patrick, W.C.; Wilder, D.G.; Brough, W.G.; Mayr, M.C.

1979-01-01

The Spent Fuel Test in the Climax granite at the Nevada Test Site is a generic test in which spent fuel assemblies from an operating commercial nuclear reactor are emplaced at, and retrieved from, a plausible waste repository depth in a typical granite. Eleven canisters of spent fuel are emplaced in a storage drift 420 m below the surface along with six electrical simulator canisters. Two adjacent drifts contain electrical heaters which are operated so as to simulate the initial five years of the temperature-stress-displacement fields of a large repository. The site is described, and the pre-operational measurement program and characteristics of the spent fuel are given. Both thermal and mechanical response calculations are summarized. The field instrumentation and data acquisition systems are described, as well as the system for handling the spent fuel

Health effects models for off-site radiological consequence analysis on nuclear reactor accidents (II)

Energy Technology Data Exchange (ETDEWEB)

Homma, Toshimitsu [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Takahashi, Tomoyuki [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst; Yonehara, Hidenori [National Inst. of Radiological Sciences, Chiba (Japan)] [eds.

2000-12-01

This report is a revision of JAERI-M 91-005, 'Health Effects Models for Off-Site Radiological Consequence Analysis of Nuclear Reactor Accidents'. This revision provides a review of two revisions of NUREG/CR-4214 reports by the U.S. Nuclear Regulatory Commission which is the basis of the JAERI health effects models and other several recent reports that may impact the health effects models by international organizations. The major changes to the first version of the JAERI health effects models and the recommended parameters in this report are for late somatic effects. These changes reflect recent changes in cancer risk factors that have come from longer followup and revised dosimetry in major studies on the Japanese A-bomb survivors. This report also provides suggestions about future revisions of computational aspects on health effects models. (author)

Health effects models for off-site radiological consequence analysis on nuclear reactor accidents (II)

International Nuclear Information System (INIS)

Homma, Toshimitsu

2000-12-01

This report is a revision of JAERI-M 91-005, 'Health Effects Models for Off-Site Radiological Consequence Analysis of Nuclear Reactor Accidents'. This revision provides a review of two revisions of NUREG/CR-4214 reports by the U.S. Nuclear Regulatory Commission which is the basis of the JAERI health effects models and other several recent reports that may impact the health effects models by international organizations. The major changes to the first version of the JAERI health effects models and the recommended parameters in this report are for late somatic effects. These changes reflect recent changes in cancer risk factors that have come from longer followup and revised dosimetry in major studies on the Japanese A-bomb survivors. This report also provides suggestions about future revisions of computational aspects on health effects models. (author)

Slow clean-up for fast reactor

Science.gov (United States)

Banks, Michael

2008-05-01

The year 2300 is so distant that one may be forgiven for thinking of it only in terms of science fiction. But this is the year that workers at the Dounreay power station in Northern Scotland - the UK's only centre for research into "fast" nuclear reactors - term as the "end point" by which time the site will be completely clear of radioactive material. More than 180 facilities - including the iconic dome that housed the Dounreay Fast Reactor (DFR) - were built at at the site since it opened in 1959, with almost 50 having been used to handle radioactive material.

ADVANTAGES, DISADVANTAGES, AND LESSONS LEARNED FROM MULTI-REACTOR DECOMMISSIONING PROJECTS

International Nuclear Information System (INIS)

Morton, M.R.; Nielson, R.R.; Trevino, R.A.

2003-01-01

This paper discusses the Reactor Interim Safe Storage (ISS) Project within the decommissioning projects at the Hanford Site and reviews the lessons learned from performing four large reactor decommissioning projects sequentially. The advantages and disadvantages of this multi-reactor decommissioning project are highlighted

Deep underground reactor (passive heat removal of LWR with hard neutron energy spectrum)

Energy Technology Data Exchange (ETDEWEB)

Hiroshi, Takahashi [Brookhaven National Lab., Upton, NY (United States)

2001-07-01

To run a high conversion reactor with Pu-Th fueled tight fueled assembly which has a long burn-up of a fuel, the reactor should be sited deep underground. By putting the reactor deep underground heat can be removed passively not only during a steady-state run and also in an emergency case of loss of coolant and loss of on-site power; hence the safety of the reactor can be much improved. Also, the evacuation area around the reactor can be minimized, and the reactor placed near the consumer area. This approach reduces the cost of generating electricity by eliminating the container building and shortening transmission lines. (author)

Deep underground reactor (passive heat removal of LWR with hard neutron energy spectrum)

International Nuclear Information System (INIS)

Hiroshi, Takahashi

2001-01-01

To run a high conversion reactor with Pu-Th fueled tight fueled assembly which has a long burn-up of a fuel, the reactor should be sited deep underground. By putting the reactor deep underground heat can be removed passively not only during a steady-state run and also in an emergency case of loss of coolant and loss of on-site power; hence the safety of the reactor can be much improved. Also, the evacuation area around the reactor can be minimized, and the reactor placed near the consumer area. This approach reduces the cost of generating electricity by eliminating the container building and shortening transmission lines. (author)

Preliminary site design for the SP-100 ground engineering test

International Nuclear Information System (INIS)

Cox, C.M.; Miller, W.C.; Mahaffey, M.K.

1986-04-01

In November, 1985, Hanford was selected by the Department of Energy (DOE) as the preferred site for a full-scale test of the integrated nuclear subsystem for SP-100. The Hanford Engineering Development Laboratory, operated by Westinghouse Hanford Company, was assigned as the lead contractor for the Test Site. The nuclear subsystem, which includes the reactor and its primary heat transport system, will be provided by the System Developer, another contractor to be selected by DOE in late FY-1986. In addition to reactor operations, test site responsibilities include preparation of the facility plus design, procurement and installation of a vacuum chamber to house the reactor, a secondary heat transport system to dispose of the reactor heat, a facility control system, and postirradiation examination. At the conclusion of the test program, waste disposal and facility decommissioning are required. The test site must also prepare appropriate environmental and safety evaluations. This paper summarizes the preliminary design requirements, the status of design, and plans to achieve full power operation of the test reactor in September, 1990

Measurement of the thermal neutron self shielding coefficient in the Syrian miniature neutron source reactor inner irradiation site using the dy soils

International Nuclear Information System (INIS)

Khattab, K.; Khamis, I.

2007-01-01

Measurement of the thermal self shielding coefficient ( Gth ) in the Syrian Miniature Neutron Source Reactor (MNSR) inner irradiation site using Dy foils is presented in this paper. The thermal self shielding coefficient is measured as a function of the foil thickness or numbers. The mathematical equation which calculates the average relative radioactivity (Bq/g) versus the foil number is found as well.

Preliminary feasibility study of modular reactors

International Nuclear Information System (INIS)

Yamaji, Kenji

1987-01-01

In the future, electric utilities will be required to make a switch-over to a more flexible and dynamic form of power supply due to the slowing growth of power demand, increasing uncertainty, the stagnating economy of increasing scale, the bottleneck of transmission and so on. Nuclear technology would also be required to adapt to this changing environment surrounding its development. The long term prospect of energy demand and nuclear power growth, and the evolution of commercial reactors in Japan are shown. The design of 1,300 MWe advanced LWRs has been completed, and as the reactors of next generation, the ultralarge LWRs of 1,500 - 1,800 MWe are suggested. However, there can be an alternative future for nuclear power development, and in this paper, the possibility for altering the image of conventional nuclear power technology by developing modular reactors which are economical even at small capacity, and can be sited in urban areas just like conventional thermal power plants is examined. The factors for the economical evaluation of modular reactors, learning effect and scale effect on the economy, the case study on a modular high temperature reactor designed by Interatom-GHT, and the possibility of siting in urban areas due to the system of inherent safety are reported. (Kako, I.)

Site suitability report in the matter of Clinch River Breeder Reactor Plant. Docket No. 50-537. Revision to March 4, 1977 report

International Nuclear Information System (INIS)

1982-06-01

In March 1977, the Office of Nuclear Reactor Regulation issued its Site Suitability Report (SSR) for the proposed Clinch River Breeder Plant (CRBRP). That SSR documents the result of the staff's evaluation of the suitability of the proposed CRBRP site for a facility of the general size and type as the CRBRP from the standpoint of radiological health and safety considerations. The staff concluded in that SSR that the proposed CRBRP site is suitable for such a facility. Since the SSR was issued, several modifications have been made to the CRBRP design, additional data related to the site and its environs have been collected, and the Fast Flux Test Facility, a technological precursor to the CRBRP, has been completed and has commenced operation. In addition, new emergency planning requirements have been promulgated by the staff. This report is an update of the March 1977 SSR that reflects these matters and discusses them in terms of the previous staff conclusion regarding the suitability of the proposed CRBRP site

Streamlined Approach for Environmental Restoration Plan for Corrective Action Unit 113: Reactor Maintenance, Assembly, and Disassembly Building Nevada Test Site, Nevada

Energy Technology Data Exchange (ETDEWEB)

J. L. Smith

2001-01-01

This Streamlined Approach for Environmental Restoration (SAFER) Plan addresses the action necessary for the closure in place of Corrective Action Unit (CAU) 113 Area 25 Reactor Maintenance, Assembly, and Disassembly Facility (R-MAD). CAU 113 is currently listed in Appendix III of the Federal Facility Agreement and Consent Order (FFACO) (NDEP, 1996). The CAU is located in Area 25 of the Nevada Test Site (NTS) and consists of Corrective Action Site (CAS) 25-04-01, R-MAD Facility (Figures 1-2). This plan provides the methodology for closure in place of CAU 113. The site contains radiologically impacted and hazardous material. Based on preassessment field work, there is sufficient process knowledge to close in place CAU 113 using the SAFER process. At a future date when funding becomes available, the R-MAD Building (25-3110) will be demolished and inaccessible radiologic waste will be properly disposed in the Area 3 Radiological Waste Management Site (RWMS).

Streamlined Approach for Environmental Restoration Plan for Corrective Action Unit 113: Reactor Maintenance, Assembly, and Disassembly Building Nevada Test Site, Nevada

International Nuclear Information System (INIS)

Smith, J. L.

2001-01-01

This Streamlined Approach for Environmental Restoration (SAFER) Plan addresses the action necessary for the closure in place of Corrective Action Unit (CAU) 113 Area 25 Reactor Maintenance, Assembly, and Disassembly Facility (R-MAD). CAU 113 is currently listed in Appendix III of the Federal Facility Agreement and Consent Order (FFACO) (NDEP, 1996). The CAU is located in Area 25 of the Nevada Test Site (NTS) and consists of Corrective Action Site (CAS) 25-04-01, R-MAD Facility (Figures 1-2). This plan provides the methodology for closure in place of CAU 113. The site contains radiologically impacted and hazardous material. Based on preassessment field work, there is sufficient process knowledge to close in place CAU 113 using the SAFER process. At a future date when funding becomes available, the R-MAD Building (25-3110) will be demolished and inaccessible radiologic waste will be properly disposed in the Area 3 Radiological Waste Management Site (RWMS)

Safety Assessment Document for the Spent Reactor Fuel Geologic Storage Test in the Climax Granite Stock at the Nevada Test site

International Nuclear Information System (INIS)

1980-01-01

The objective of the Spent Fuel Geologic Storage Test in the Climax Granite Stock is to evaluate the response of a granitic rock mass to the underground storage of encapsulated spent reactor fuel in a geometry that simulates a module of a large-scale geologic repository. This document reports an assessment of the safety of conducting this test. Descriptions are provided of the geography, meteorology, hydrology, geology, and seismology of the Climax Site; the effects of postulated natural phenomena and other activities at the nevada Test Site on the safety of the test; and the design and operation of the test facility and associated equipment. Evaluations are made of both the radiological and nonradiological impacts of normal operations, abnormal operations, and postulated accidents. It is concluded that conduct of the spent fuel test at the Climax Site will not result in any undue risk to the public, property, environment, or site employees

The timing of reactor dismantling

International Nuclear Information System (INIS)

Roberts, P.

2000-01-01

Work has been progressing across the world for the decommissioning of nuclear reactors. The initial work focused on the early, complete dismantling but this was associated with small size reactors and was done for experimental or demonstration purposes. The situation now is that an increasing number of full size power reactors are being shutdown and decision are being made as to the decommissioning strategy to be applied, e.g. with respect to the appropriate timing of reactor dismantling. There are two basic approaches to the timing of reactor dismantling, which are to either proceed with dismantling on an early time scale or to delay it for a period of years. There are a number of examples worldwide of both approaches being taken but one common feature of the approach taken by most countries is that decisions are made on a case by case basis, taking account of relevant factors, and as a result the strategy can vary from reactor to reactor and from country to country. Decisions on timing take account of the following main factors: safety, radioactive decay, financial factors, radioactive waste, reactor type, technology, repository availability, site re-use, regulatory standards, plant knowledge/records, other issues

Astrid (fast breeder nuclear reactor)

International Nuclear Information System (INIS)

2014-01-01

This document presents ASTRID (Advanced Sodium Technological Reactor for Industrial Demonstration), a French project of sodium-cooled fast breeder reactor, fourth generation reactor which should be fuelled by uranium 238 rather than uranium 235, and should therefore need less extracted natural uranium to produce electricity. The operation principle of fast breeder reactors is described. They notably directly consume plutonium, allow an easier radioactive waste management as they transform long life radioactive elements into shorter life elements by transmutation. The regeneration process is briefly described, and the various operation modes are evoked (iso-generator, sub-generator, and breeder). Some peculiarities of sodium-cooled reactors are outlined. The Astrid operation principle is described, its main design innovations outlined. Various challenges are discussed regarding safety of supply and waste processing, and the safety of future reactors. Major actors are indicated: CEA, Areva, EDF, SEIV Alcen, Toshiba, Rolls Royce, and Comex. Some key data are indicated: expected lifetime, expected availability rate, cost. The projected site is Marcoule and fast breeder reactors operated or under construction in the world are indicated. The document also proposes an overview of the background and evolution of reactors of 4. generation

Status of fast reactor activities in the USSR

International Nuclear Information System (INIS)

Troyanov, M.F.; Rinejskij, A.A.

1990-01-01

Four fast reactors are in operation in the USSR now: BR-10, BOR-60, BN-350 and BN-600. Load factor of BN-600 reactor was in 1989 about 76%. On the basis of operational experience of running reactors design of more powerful commercial size BN-800 power reactor has been completed recently and construction work has started at two sites. The BN-1600 reactor is considered to be the prototype of future commercial reactors. In 1990, it was decided to extend its design approach with the aim to find some additional solutions to provide higher safety and better economics. (author). Figs and tabs

Lesson Learned in Preparation for Decommissioning of Three Canadian Prototype Power Reactors

International Nuclear Information System (INIS)

Vickerd, Meggan; Kenny, Stephen

2016-01-01

Lesson learned by Canadian Nuclear Laboratories (CNL)(former AECL) in preparation for decommissioning of three Prototype Reactors is a result of various strategies used for each site. CNL is responsible for the eventual decommissioning of three prototype power reactors; Nuclear Power Demonstration (NPD), Gentilly-1 and Douglas Point. Each of the Canadian prototype power reactor sites shutdown using different strategies. Depending on the site location, configuration, and intended designation of the respective sites, the individual facility systems (ventilation, electrical system, fire detection etc.) were also shut down using different strategies and operating objectives. As CNL embarks on decommissioning the first Canadian prototype reactor, this paper will reflect on the lessons learned over the past thirty years and what CNL is adjusting in the decommissioning strategy to prepare better plans for the future. The Nuclear Power Demonstration Nuclear Generating Station (NPDNGS) was constructed in late 1950's and operated from 1962 to 1987 when it was permanently shutdown after exceeding its operational goals. The NPD reactor was the first Canadian nuclear power reactor and it consisted of a single 20 MWe pressurized heavy water reactor located on a single facility site in Rolphton, Ontario. The NPD facility was shutdown to a 'Cold, Dark and Quiet' state and is maintained using an unmanned strategy by managing the site remotely with active fire detection and security surveillance systems, minimal electrical supply and an active ventilation system which is operated periodically to allow for intermittent inspections. The Douglas Point Nuclear Generating Station (DPNGS) was constructed in the early 1960's and operated from 1968 to 1984 when it was permanently shutdown. It consisted of a 200 MW prototype Canada Deuterium Uranium (CANDU) reactor and is embedded on the Bruce Power site near Kincardine, Ontario. The Douglas Point site is maintained in a

Underground reactor containments: An option for the future?

International Nuclear Information System (INIS)

Forsberg, C.W.; Kress, T.

1997-01-01

Changing world conditions and changing technologies suggest that serious consideration should be given to siting of nuclear power plants underground. Underground siting is not a new concept. Multiple research reactors, several weapons production reactors, and one power reactor have been built underground. What is new are the technologies and incentives that may now make underground siting a preferred option. The conditions and technologies, along with their implications, are discussed herein. Underground containments can be constructed in mined cavities or pits that are then backfilled with thick layers of rock and soil. Conventional above-ground containments resist assaults and accidents because of the strength of their construction materials and the effectiveness of their safety features that are engineered to reduce loads. However, underground containments can provide even more resistance to assaults and accidents because of the inertia of the mass of materials over the reactor. High-technology weapons or some internal accidents can cause existing strong-material containments to fail, but only very-high energy releases can move large inertial masses associated with underground containments. New methods of isolation may provide a higher confidence in isolation that is independent of operator action

Decommissioning of multiple-reactor stations: facilitation by sequential decommissioning

International Nuclear Information System (INIS)

Moore, E.B.; Smith, R.I.; Wittenbrock, N.G.

1982-01-01

Reductions in cost and radiation dose can be achieved for decommissionings at multiple reactor stations because of factors not necessarily present at a single reactor station: reactors of similar design, the opportunity for sequential decommissioning, a site dedicated to nuclear power generation, and the option of either interim or permanent low-level radioactive waste storage facilities onsite. The cost and radiation dose reductions occur because comprehensive decommissioning planning need only be done once, because the labor force is stable and need only be trained once, because there is less handling of radioactive wastes, and because central stores, equipment, and facilities may be used. The cost and radiation dose reductions are sensitive to the number and types of reactors on the site, and to the alternatives selected for decommissioning. 3 tables

An analysis of decommissioning costs for the AFRRI TRIGA reactor facility

International Nuclear Information System (INIS)

Forsbacka, Matt

1990-01-01

A decommissioning cost analysis for the AFRRI TRIGA Reactor Facility was made. AFRRI is not at this time suggesting that the AFRRI TRIGA Reactor Facility be decommissioned. This report was prepared to be in compliance with paragraph 50.33 of Title 10, Code of Federal Regulations which requires the assurance of availability of future decommissioning funding. The planned method of decommissioning is the immediate decontamination of the AFRRI TRIGA Reactor site to allow for restoration of the site to full public access - this is called DECON. The cost of DECON for the AFRRI TRIGA Reactor Facility in 1990 dollars is estimated to be $3,200,000. The anticipated ancillary costs of facility site demobilization and spent fuel shipment is an additional $600,000. Thus the total cost of terminating reactor operations at AFRRI will be about $3,800,000. The primary basis for this cost estimate is a study of the decommissioning costs of a similar reactor facility that was performed by Battelle Pacific Northwest Laboratory (PNL) as provided in USNRC publication NUREG/CR-1756. The data in this study were adapted to reflect the decommissioning requirements of the AFRRI TRIGA. (author)

Sites for locations of nuclear reactors; Sitios para emplazamientos de reactores nucleares

Energy Technology Data Exchange (ETDEWEB)

Balcazar, M.; Huerta, M.; Lopez, A., E-mail: miguel.balcazar@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

2014-10-15

A restriction on sites of nuclear energy is the history of seismic activity, in its magnitude (Richter) and intensity (Mercalli). This article delimits the areas of greatest magnitude and national seismic intensity, with restrictions of ground acceleration; the supplement areas with a low magnitude of seismic activity are shown. Potential sites for the location of these sites are introduced into a geographic information system. The set of geo-referenced data contains the location of the active volcanic manifestations; the historical record of earthquake epicenters, magnitudes and intensities; major geological faults; surface hydrology and water bodies; location of population density; protected areas; contour lines; the rock type or geology. The geographic information system allows entering normative criteria and environmental restrictions that correlate with geo-referenced data described above, forms both probable and exclusion areas for the installation of nuclear sites. (Author)

Impact of proposed research reactor standards on reactor operation

Energy Technology Data Exchange (ETDEWEB)

Ringle, J C; Johnson, A G; Anderson, T V [Oregon State University (United States)

1974-07-01

A Standards Committee on Operation of Research Reactors, (ANS-15), sponsored by the American Nuclear Society, was organized in June 1971. Its purpose is to develop, prepare, and maintain standards for the design, construction, operation, maintenance, and decommissioning of nuclear reactors intended for research and training. Of the 15 original members, six were directly associated with operating TRIGA facilities. This committee developed a standard for the Development of Technical Specifications for Research Reactors (ANS-15.1), the revised draft of which was submitted to ANSI for review in May of 1973. The Committee then identified 10 other critical areas for standards development. Nine of these, along with ANS-15.1, are of direct interest to TRIGA owners and operators. The Committee was divided into subcommittees to work on these areas. These nine areas involve proposed standards for research reactors concerning: 1. Records and Reports (ANS-15.3) 2. Selection and Training of Personnel (ANS-15.4) 3. Effluent Monitoring (ANS-15.5) 4. Review of Experiments (ANS-15.6) 5. Siting (ANS-15.7) 6. Quality Assurance Program Guidance and Requirements (ANS-15.8) 7. Restrictions on Radioactive Effluents (ANS-15.9) 8. Decommissioning (ANS-15.10) 9. Radiological Control and Safety (ANS-15.11). The present status of each of these standards will be presented, along with their potential impact on TRIGA reactor operation. (author)

Impact of proposed research reactor standards on reactor operation

International Nuclear Information System (INIS)

Ringle, J.C.; Johnson, A.G.; Anderson, T.V.

1974-01-01

A Standards Committee on Operation of Research Reactors, (ANS-15), sponsored by the American Nuclear Society, was organized in June 1971. Its purpose is to develop, prepare, and maintain standards for the design, construction, operation, maintenance, and decommissioning of nuclear reactors intended for research and training. Of the 15 original members, six were directly associated with operating TRIGA facilities. This committee developed a standard for the Development of Technical Specifications for Research Reactors (ANS-15.1), the revised draft of which was submitted to ANSI for review in May of 1973. The Committee then identified 10 other critical areas for standards development. Nine of these, along with ANS-15.1, are of direct interest to TRIGA owners and operators. The Committee was divided into subcommittees to work on these areas. These nine areas involve proposed standards for research reactors concerning: 1. Records and Reports (ANS-15.3) 2. Selection and Training of Personnel (ANS-15.4) 3. Effluent Monitoring (ANS-15.5) 4. Review of Experiments (ANS-15.6) 5. Siting (ANS-15.7) 6. Quality Assurance Program Guidance and Requirements (ANS-15.8) 7. Restrictions on Radioactive Effluents (ANS-15.9) 8. Decommissioning (ANS-15.10) 9. Radiological Control and Safety (ANS-15.11). The present status of each of these standards will be presented, along with their potential impact on TRIGA reactor operation. (author)

SIR - small is safe [in reactor design

International Nuclear Information System (INIS)

Hayns, M.

1989-01-01

A joint USA-UK venture has been initiated to design a small nuclear reactor which offers low capital cost, greater flexibility and a potentially lower environmental impact. Called Safe Integral Reactor (SIR), the lead unit could be built in the United Kingdom Atomic Energy Authority's (UKAEA's) Winfrith site if the design is accepted by the UK Nuclear Installations Inspectorate (NII). This article describes the 320 MWe reactor unit that is the basis of the design being developed. (author)

Small reactor operating mode

International Nuclear Information System (INIS)

Snell, V.G.

1997-01-01

There is a potential need for small reactors in the future for applications such as district heating, electricity production at remote sites, and desalination. Nuclear power can provide these at low cost and with insignificant pollution. The economies required by the small scale application, and/or the remote location, require a review of the size and location of the operating staff. Current concepts range all the way from reactors which are fully automatic, and need no local attention for days or weeks, to those with reduced local staff. In general the less dependent a reactor is on local human intervention, the greater its dependence on intrinsic safety features such as passive decay heat removal, low-stored energy and limited reactivity speed and depth in the control systems. A case study of the design and licensing of the SLOWPOKE Energy System heating reactor is presented. (author)

Application of Emergency Action Levels from Potential Release at Research Reactor HANARO

International Nuclear Information System (INIS)

Kim, Jongsoo; Lee, Goan Yub; Lee, Hae Choi; Kim, Bong Suk

2014-01-01

Execution of the protective action promptly is possible that Emergency Action Levels (EALs) must be established for a radiological release from nuclear facility. The EALs for electric power reactor are already developed and applied to recognize an emergency situation rapidly. Recently the IAEA published the safety report including the EALs for research reactor. This paper describes the EALs to apply for a potential release pathway at the research reactor HANARO. The results of table 1 and 2 will be higher than actual because the weather condition in real situation is difference. However, the EALs applying the potential stack release, ground release and site can be useful for research reactor HANARO making the emergency declaration. The EALs at the site boundary of the table 3 can be applied to protect the off-site public

Remote technology in RBMK-1000 spent fuel management at NPP site

International Nuclear Information System (INIS)

Makarchuk, T.F.; Kozlov, Y.V.; Tikhonov, N.S.; Tokarenko, A.I.; Spichev, V.V.; Kaljazin, N.N.

1999-01-01

The report describes the remote technologies employed in the nuclear power plant with RBMK-1000 type. Spent fuel transfer and handling operations at reactor (AR) and away from reactor (AFR) on reactor site (RS) facilities are illustrated by the example of the Leningradskaya NPP and are typical for all NPPs with RBMK-1000. The current approach to spent fuel management at NPP sites is also presented. (author)

Manufacture and installation of reactor auxiliary facilities for advanced thermal prototype reactor 'Fugen'

International Nuclear Information System (INIS)

Kawahara, Toshio; Matsushita, Tadashi

1977-01-01

The facilities of reactor auxiliary systems for the advanced thermal prtotype reactor ''Fugen'' were manufactured in factories since 1972, and the installation at the site began in November, 1974. It was almost completed in March, 1977, except a part of the tests and inspections, therefore the outline of the works is reported. The ATR ''Fugen'' is a heavy water-moderated, boiling light water reactor, and its reactor auxiliary systems comprise mainly the facilities for handling heavy water, such as heavy water cooling system, heavy water cleaning system, poison supplying system, helium circulating system, helium cleaning system, and carbon dioxide system. The poison supplying system supplies liquid poison to the heavy water cooling system to absorb excess reactivity in the initial reactor core. The helium circulating system covers heavy water surface with helium to prevent the deterioration of heavy water and maintains heavy water level by pressure difference. The carbon dioxide system flows highly pure CO 2 gas in the space of pressure tubes and carandria tubes, and provides thermal shielding. The design, manufacture and installation of the facilities of reactor auxiliary systems, and the helium leak test, synthetic pressure test and total cleaning are explained. (Kako, I.)

Hanford B Reactor Building Hazard Assessment Report

International Nuclear Information System (INIS)

Griffin, P. W.

1999-01-01

The 105-B Reactor (hereinafter referred to as B Reactor) is located in the 100 Area of the Hanford Site near Richland, Washington. The B Reactor is one of nine plutonium production reactors that were constructed in the 1940s during the Cold War Era. Construction of the B Reactor began June 7, 1943, and operation began on September 26, 1944. The Environmental Restoration Contractor was requested by RL to provide an assessment/characterization of the B Reactor building to determine and document the hazards that are present and could pose a threat to the environment and/or to individuals touring the building. This report documents the potential hazards, determines the feasibility of mitigating the hazards, and makes recommendations regarding areas where public tour access should not be permitted

Metropolitan siting: a historical perspective

International Nuclear Information System (INIS)

Bunch, D.F.

1978-09-01

The paper discusses the development and implementation of the Reactor Site Criteria and particularly the evolving posture of the agency on the subject of metropolitan siting. The review actions on nine sites are described to illustrate the various issues and positions and to clarify at least some of the bases for current practices of the NRC staff

Reactor Antineutrinos Signal all over the world

OpenAIRE

Ricci, B.; Mantovani, F.; Baldoncini, M.; Esposito, J.; Ludhova, L.; Zavatarelli, S.

2014-01-01

We present an updated estimate of reactor antineutrino signal all over the world, with particular attention to the sites proposed for existing and future geo-neutrino experiment. In our calculation we take into account the most updated data on Thermal Power for each nuclear plant, on reactor antineutrino spectra and on three neutrino oscillation mechanism.

Marine reactor pressure vessels dumped in the Kara Sea

International Nuclear Information System (INIS)

Mount, M.E.

1997-01-01

Between 1965 and 1988, 16 marine reactors from seven Russian submarines and the icebreaker Lenin, each of which suffered some form of reactor accident, were dumped in a variety of containments, using a number of sealing methods, at five sites in the Kara Sea. All reactors were dumped at sites that varied in depth from 12 to 300 m and six contained their spent nuclear fuel (SNF). This paper examines the breakdown of the reactor pressure vessel (RPV) barriers due to corrosion, with specific emphasis on those RPVs containing SNF. Included are discussions of the structural aspects of the steam generating installations and their associated RPVs, a summary of the disposal operations, assumptions on corrosion rates of structural and filler materials, and an estimate of the structural integrity of the RPVs at the present time (1996) and in the year 2015

Passive cooling of a fixed bed nuclear reactor

International Nuclear Information System (INIS)

Petry, V.J.; Bortoli, A.L. de; Sefidwash, F.

2005-01-01

Small nuclear reactors without the need for on-site refuelling have greater simplicity, better compliance with passive safety systems, and are more adequate for countries with small electric grids and limited investment capabilities. Here the passive cooling characteristic of the fixed bed nuclear reactor (FBNR), that is being developed under the International Atomic Energy Agency (IAEA) Coordinated Research Project, is studied. A mathematical model is developed to calculate the temperature distribution in the fuel chamber of the reactor. The results demonstrate the passive cooling of this nuclear reactor concept. (authors)

Preliminary conceptual design for electrical and I and C system of a new research reactor

International Nuclear Information System (INIS)

Jung, Hoan Sung; Kim, Y. K.; Kim, M. J.; Kim, H. K.; Ryu, J. S.

2004-01-01

The core type and the process system design will be varied according to the reactor's application and capacity. A New research reactor is being designed by KAERI since 2002 and the process systems are not fixed yet. But control and instrument systems are similar to each other even though the application and the size are not same. So the C and I system that encompasses reactor protection system, reactor control system, and computer system was designed conceptually according to the requirements based on new digital technology and HANARO's proven design. The plant electrical system consists of off-site system that delivers bulk electrical power to the reactor site and on-site system that distributes and controls electrical power at the facility. The electrical system includes building service system that consist of lighting, communication, fire detection, grounding, cathodic protection, etc. also. This report describes the design requirements of on-site and off-site electric power system that set up from the codes and standards and the conceptual design based on the design requirements

Reactor system on barge

International Nuclear Information System (INIS)

Hayashi, Kingo; Yamada, Nobuyuki

1987-01-01

Floating electrical power plants or power plant barges add new dimensions to utility planners and agencies in the world. Intrinsically safe and economical reactors (ISER) employ steel reactor pressure vessels, which significantly reduce the weight as compared with PIUS, and provide siting versatility including barge-mounted plants. In this paper, the outline of power plant barges and barge-mounted ISERs is described. Besides their mobility, power plant barges have the salient advantages such as short delivery time and better quality control due to the outfitting in shipyards. These power plant barges may be temporarily moored or permanently grounded in shallow water at the centers of industrial complexes or the suitable areas adjacent to them, and satisfy the increasing needs for electric power. A cost-effective and technically perfect barge positioning system should be designed to meet the specific requirement for the location and its condition. Offshore siting away from coast may be applicable only to large plants of 1,000 MWe or more, and inshore siting and coastal or river siting are considered for an ISER-200 barge-mounted plant. The system of a barge-mounted ISER plant is discussed in the case of a floating type and the type on a seismic base isolator. (Kako, I.)

A role of small reactors in the latter part of 21st century

International Nuclear Information System (INIS)

Sekimoto, H.

2004-01-01

In the year 2002 and 2003 the Japanese Ministry of Education, Culture, Sports, Science and Technology started the Priority Assistance for the Formation of Worldwide Renowned Centers of Research - The 21st Century Center of Excellence (COE) Program. A program proposed by Tokyo Institute of Technology Innovative Nuclear Energy Systems for Sustainable Development of the World was selected as only one program in nuclear engineering. In this program the system of nuclear energy park and small reactors will be intensively investigated. Here the small reactors are constructed in the nuclear energy park and transferred to the site and set there. The reactor vessel is sealed and can not be opened at the site. It is excellent from the nonproliferation point of view. It is also good from safety and easy maintenance, since refueling is not performed at the site. At the end of the reactor life it is replace by a new one. The old one will be shipped to the nuclear energy park. There is not radioactive wastes left at the site, the site is free from the waste problems. At the conference presented are the details of the considered nuclear energy park and a proposed design of the small reactor.(author)

Gamma monitoring system 'Hyperion' at the research nuclear reactor RB

International Nuclear Information System (INIS)

Zigic, A.; Saponjic, Dj.; Arandelovic, V. . E-mail address of corresponding author: alex@vin.bg.ac.yu

2005-01-01

While performing experiments at the research reactor RB at Vinca institute it is mandatory to measure the intensity of gamma radiation at reactor RB since the reactor has no biological protection. the stationary distributed measurement system 'Hyperion' implemented at reactor RB, performs measurements and monitoring of gamma radiation at 10 specified measuring sites within and in the vicinity of the reactor RB in the required absorbed dose in air range of 50 nGy/h to 10 mGy/h. the 'Hyperion' monitoring system have three hierarchically organized layers. the basic layer consists of the network of 10 intelligent gm probes located at predetermined measuring sites. the medium layer represents the PC-based local control node where measured data from all intelligent probes are separately acquired, stored in the local database and processed for local visualization and printed measurements reports for network operator. the information on the status of the intelligent gm probes are also provided, enabling the verification of measured results at the local control node. the central control node represents the pc-based highest monitoring network layer connected to the local control node using already existing lan infrastructure. the central control node hosts the central database, provides full insight into instantaneous gamma radiation levels at all measuring sites, provides archives on daily bases for all monitored locations and printed reports on measurements for all measuring sites at any time of gamma radiation measurement. (author)

Reactor Physics Behind the Chernobyl Accident

International Nuclear Information System (INIS)

Reisch, F.

1999-01-01

There are some fourteen Chernobyl type of power reactors (1000 MWe) in operation at five different sites in Eastern Europe. In Russia; in St. Petersburg (4). in Smolensk (3). and in Kursk (4) in the Ukraine in Chernobyl (l) and in Lithuania in Ignalina (2). The oldest one is west of St. Petersburg and the most powerful one is in Ignalina. The reactors at St. Petersburg and in Lithuania are near to the Baltic sea. An intricate reactor construction was the most important cause of the accident. There were other reasons too: human error. politics and economics

Transmutation of Americium in Light and Heavy Water Reactors

Energy Technology Data Exchange (ETDEWEB)

Hyland, B.; Dyck, G.R.; Edwards, G.W.R. [Chalk River Laboratories, Atomic Energy of Canada Limited (Canada); Ellis, R.J.; Gehin, J.C. [Oak Ridge National Laboratory (ORNL), Oak Ridge, Tennessee (United States); Maldonado, G.I. [University of Tennessee (Knoxville)/ORNL, Tennessee (United States)

2009-06-15

There is interest worldwide in reducing the burden on geological nuclear fuel disposal sites. In most disposal scenarios the decay heat loading of the surrounding rock limits the capacity of these sites. On the long term, this decay heat is generated primarily by actinides, and a major contributor 100 to 1000 years after discharge from the reactor is {sup 241}Am. One possible approach to reducing the decay-heat burden is to reprocess spent reactor fuel and use thermal spectrum reactors to 'burn' the Am nuclides. The viability of this approach is dependent upon the detailed changes in chemical and isotopic composition of actinide-bearing fuels after irradiation in thermal reactor spectra. The currently available thermal spectrum reactor options include light water-reactors (LWRs) and heavy-water reactors (HWRs) such as the CANDU{sup R} designs. In addition, as a result of the recycle of spent LWR fuel, there would be a considerable amount of potential recycled uranium (RU). One proposed solution for the recycled uranium is to use it as fuel in Candu reactors. This paper investigates the possibilities of transmuting americium in 'spiked' bundles in pressurized water reactors (PWRs) and in boiling water reactors (BWRs). Transmutation of Am in Candu reactors is also examined. One scenario studies a full core fuelled with homogeneous bundles of Am mixed with recycled uranium, while a second scenario places Am in an inert matrix in target channels in a Candu reactor, with the rest of the reactor fuelled with RU. A comparison of the transmutation in LWRs and HWRs is made, in terms of the fraction of Am that is transmuted and the impact on the decay heat of the spent nuclear fuel. CANDU{sup R} is a registered trademark of Atomic Energy of Canada Limited (AECL). (authors)

Restart of K-Reactor, Savannah River Site: Safety evaluation report

Energy Technology Data Exchange (ETDEWEB)

1991-04-01

This Safety Evaluation Report (SER) focuses on those issues required to support the restart of the K-Reactor at the Savannah River Plant. This SER provides the safety criteria for restart and documents the results of the staff reviews of the DOE and operating contractor activities to meet these criteria. To develop the restart criteria for the issues discussed in this SER, the Savannah River Restart Office and Savannah River Special Projects Office staffs relied, when possible, on commercial industry codes and standards and on NRC requirements and guidelines for the commercial nuclear industry. However, because of the age and uniqueness of the Savannah River reactors, criteria for the commercial plants were not always applicable. In these cases, alternate criteria were developed. The restart criteria applicable to each of the issues are identified in the safety evaluations for each issue. The restart criteria identified in this report are intended to apply only to restart of the Savannah River reactors. Following the development of the acceptance criteria, the DOE staff and their support contractors evaluated the results of the DOE and operating contractor (WSRC) activities to meet these criteria. The results of those evaluations are documented in this report. Deviations or failures to meet the requirements are either justified in the report or carried as open or confirmatory items to be completed and evaluated in supplements to this report before restart. 62 refs., 1 fig.

Restart of K-Reactor, Savannah River Site: Safety evaluation report

International Nuclear Information System (INIS)

1991-04-01

This Safety Evaluation Report (SER) focuses on those issues required to support the restart of the K-Reactor at the Savannah River Plant. This SER provides the safety criteria for restart and documents the results of the staff reviews of the DOE and operating contractor activities to meet these criteria. To develop the restart criteria for the issues discussed in this SER, the Savannah River Restart Office and Savannah River Special Projects Office staffs relied, when possible, on commercial industry codes and standards and on NRC requirements and guidelines for the commercial nuclear industry. However, because of the age and uniqueness of the Savannah River reactors, criteria for the commercial plants were not always applicable. In these cases, alternate criteria were developed. The restart criteria applicable to each of the issues are identified in the safety evaluations for each issue. The restart criteria identified in this report are intended to apply only to restart of the Savannah River reactors. Following the development of the acceptance criteria, the DOE staff and their support contractors evaluated the results of the DOE and operating contractor (WSRC) activities to meet these criteria. The results of those evaluations are documented in this report. Deviations or failures to meet the requirements are either justified in the report or carried as open or confirmatory items to be completed and evaluated in supplements to this report before restart. 62 refs., 1 fig

Structural and piping issues in the design certification of advanced reactors

International Nuclear Information System (INIS)

Ali, S.A.; Terao, D.; Bagchi, G.

1996-01-01

The purpose of this paper is to discuss the design certification of structures and piping for evolutionary and passive advanced light water reactors. Advanced reactor designs are based on a set of assumed site-related parameters that are selected to envelop a majority of potential nuclear power plant sites. Multiple time histories are used as the seismic design basis in order to cover the majority of potential sites in the US. Additionally, design are established to ensure that surface motions at a particular site will not exceed the enveloped standard design surface motions. State-of-the-art soil-structure interaction (SSI) analyses have been performed for the advanced reactors, which include structure-to-structure interaction for all seismic Category 1 structures. Advanced technology has been utilized to exclude the dynamic effects of pipe rupture from structural design by demonstrating that the probability of pipe rupture is extremely low. For piping design, the advanced reactor vendors have developed design acceptance criteria (DAC) which provides the piping design analysis methods, design procedures, and acceptance criteria. In SECY-93-087 the NRC staff recommended that the Commission approve the approach to eliminate the OBE from the design of structures and piping in advanced reactors and provided guidance which identifies the necessary changes to existing seismic design criteria. The supplemental criteria address fatigue, seismic anchor motion, and piping stress limits when the OBE is eliminated

MLR reactor

International Nuclear Information System (INIS)

Ryazantsev, E.P.; Egorenkov, P.M.; Nasonov, V.A.; Smimov, A.M.; Taliev, A.V.; Gromov, B.F.; Kousin, V.V.; Lantsov, M.N.; Radchenko, V.P.; Sharapov, V.N.

1998-01-01

The Material Testing Loop Reactor (MLR) development was commenced in 1991 with the aim of updating and widening Russia's experimental base to validate the selected directions of further progress of the nuclear power industry in Russia and to enhance its reliability and safety. The MLR reactor is the pool-type one. As coolant it applies light water and as side reflector beryllium. The direction of water circulation in the core is upward. The core comprises 30 FA arranged as hexagonal lattice with the 90-95 mm pitch. The central materials channel and six loop channels are sited in the core. The reflector includes up to 11 loop channels. The reactor power is 100 MW. The average power density of the core is 0.4 MW/I (maximal value 1.0 MW/l). The maximum neutron flux density is 7.10 14 n/cm 2 s in the core (E>0.1 MeV), and 5.10 14 n/cm 2 s in the reflector (E<0.625 eV). In 1995 due to the lack of funding the MLR designing was suspended. (author)

At-reactor storage concepts criteria for preliminary assessment

International Nuclear Information System (INIS)

Boydston, L.A.

1981-12-01

The licensing, safety, and environmental considerations of four wet and four dry at-reactor storage concepts are presented. Physical criteria for each concept are examined to determine the minimum site and facility requirements which must be met by a utility which desires to expand its at-reactor spent fuel storage capability

Neutronics comparative analysis between MNSR and slowpoke-II reactors

International Nuclear Information System (INIS)

Khamis, I.; Khattab, K.

1999-01-01

Neutronics analysis of both MNSR and Slowpoke reactors were made. Calculations including flux distribution, power estimation, excess and shutdown reactivity margins, flooding effects of irradiation sites, and initial investigation of fuel conversion from high to low enriched uranium were discussed. A neutronic 3-D model, dedicated mainly for the MNSR, has been developed to perform such neutronic calculations for both reactors. Well-known cell and core calculation codes such as WIMSD4 and CITATIONS have been used. It was found out that it is possible to lower the fuel enrichment of the Miniature Neutron Source Reactor (MNSR) to 20% using U O 2 as fuel instead of U Al 4 . The number of fuel elements required for the new core is 199. The use of double thickness of the bottom reflector in Slowpoke reactor made it possible to load the reactor with lower enriched fuel compared to MNSR. Values of reactivity flooding effects for single or combination of inner irradiation sites were obtained accurately. Results show good agreement with reported data for MNSR. (author)

Overview of clustered nuclear siting and its technical aspects

International Nuclear Information System (INIS)

Meier, P.M.

1976-09-01

In recent years there has been growing discussion over the ability of new siting approaches to redress the increasing problems of nuclear plant location. This debate has focused largely on three alternatives to the conventional siting of nuclear reactors; floating offshore plants; underground siting; and nuclear energy centers (NECs) consisting of up to 40 reactors at a single site, and, possibly, including fuel cycle facilities within their perimeter. Congressional interest in energy centers, especially in view of concern over the proliferation of nuclear reactors throughout the country, and with the special problems of safeguards over fuel reprocessing and the use of plutonium as a reactor fuel, resulted in a mandate to the Nuclear Regulatory Commission to make a comprehensive analysis of the energy center concept. A common finding of all of the studies of the nuclear energy center concept thus far is that there appear to be no technical considerations that would clearly preclude energy centers. With the one significant exception regarding the meteorological impacts of the concentration of heat and moisture releases to the atmosphere, engineering solutions would appear to be quite adequate to address any difficulties of environmental impact, electrical systems management, water supply or construction management, and to keep the overall physical environmental impact of an energy center not significantly different to that of an equivalent number of dispersed reactors

A robot-automated work site for repair of the Chinon A3 reactor

International Nuclear Information System (INIS)

Raynal, A.

1987-01-01

In 1982, following degradation due to corrosion of low-carbon steel by carbon dioxide gas, the utility undertook to repair some of the support structures at Chinon A3. This involved consolidation and reinforcing thermocouples and gas monitor pipeworks supports. A welding process was selected and the use of robots became indispensable because of the large number of components to be replaced (200 per outage). Two robots, supplied with tool heads and replacement components from outside the reactor were used. The robots and their servers were coordinated by a central computer and monitored by a closed circuit television system. Each repair operation was performed after ''training'' on a full-scale mockup of the top of the reactor reconstructed from telemetry of the real reactor dimensions. Since becoming operational in June 1986, the robots have accumulated over 20 000 hours of operation and seventy parts have been welded to the reactor. A 3D CAD system has been adapted to simulate the robots and analyse long trajectories in order to reduce robot learning time [fr

Fuel assembly transfer and storage system for nuclear reactors

International Nuclear Information System (INIS)

Allain, Albert; Thomas, Claude.

1981-01-01

Transfer and storage system on a site comprising several reactors and at least one building housing the installations common to all these reactors. The system includes: transfer and storage modules for the fuel assemblies comprising a containment capable of containing several assemblies carried on a transport vehicle, a set of tracks for the modules between the reactors and the common installations, handling facilities associated with each reactor for moving the irradiated assemblies from the reactor to a transfer module placed in loading position on a track serving the reactor and conversely to move the new assemblies from the transfer module to the reactor, and at least one handling facility located in the common installation building for loading the modules with new assemblies [fr

Optimising end of generation of Magnox reactors

International Nuclear Information System (INIS)

Hall, D.; Hopper, E.D.A.

2014-01-01

Designing, justifying and gaining regulatory approval for optimised, terminal fuel cycles for the last 4 of the 13 strong Magnox Fleet is described, covering: - constraints set by the plant owner's integrated closure plan, opportunities for innovative fuel cycles while preserving flexibility to respond to business changes; - methods of collectively determining best options for each site; - selected strategies including lower fuel element retention and inter-reactor transfer of fuel; - the required work scope, its technical, safety case and resource challenges and how they were met; - achieving additional electricity generation worth in excess of Pound 1 b from 4 sites (a total of 8 reactors); - the keys to success. (authors)

OSIRIS Nuclear Reactors and Services Department

International Nuclear Information System (INIS)

2008-01-01

OSIRIS is an experimental reactor with a thermal power of 70 megawatts. It is a light-water reactor, open-core pool type, the principal aim of which is to carry out tests and irradiate the fuel elements and structural materials of nuclear power stations under a high flux of neutrons, and to produce radioisotopes. Located within the French Atomic Energy Commission (CEA) centre at Saclay, it is close to many research teams and inspection laboratories and has a large-scale technological infrastructure. After a presentation of the characteristics of the reactor, the document presents its irradiation positions and experimental conditions (Geometry, Neutron flux, Gamma heating) and its experimental devices (CHOUCA, IRMA, PHAETON, GRIFFONOS, ISABELLE loops, MERCI, IRIS, Instrumentation of the devices, Qualification of the instrumentation). A forth part presents the facilities that are provided to guarantee the quality of the irradiations carried out in the reactor: ISIS reactor model, hot cells, non-destructive inspection means, chemical control of the water, tools for on-line data acquisition and follow-up of experiments, and the calculation and modelling group. A last part is devoted to the hot labs associated to OSIRIS: the LECI, a hot laboratory located on the Saclay site and mainly designed for the study of irradiated materials, and the LECA and STAR facilities, located on the CEA site in Cadarache in the south of France, and which supplement those of Saclay for fuel studies

Decommissioning of Salaspils nuclear reactor

International Nuclear Information System (INIS)

Abramenkovs, A.; Malnachs, J.; Popelis, A.

2002-01-01

In May 1995, the Latvian Government decided to shut down the Research Reactor Salaspils (SRR) and to dispense with nuclear energy in future. The reactor has been out of operation since July 1998. A conceptual study for the decommissioning of SRR has been carried out by Noell-KRC-Energie- und Umwelttechnik GmbH from 1998-1999. he Latvian Government decided on 26 October 1999 to start the direct dismantling to 'green field' in 2001. The results of decommissioning and dismantling performed in 1999-2001 are presented and discussed. The main efforts were devoted to collecting and conditioning 'historical' radioactive waste from different storages outside and inside the reactor hall. All radioactive material more than 20 tons were conditioned in concrete containers for disposal in the radioactive waste depository 'Radons' in the Baldone site. Personal protective and radiation measurement equipment was upgraded significantly. All non-radioactive equipment and material outside the reactor buildings were free-released and dismantled for reuse or conventional disposal. Weakly contaminated material from the reactor hall was collected and removed for free-release measurements. The technology of dismantling of the reactor's systems, i.e. second cooling circuit, zero power reactors and equipment, is discussed in the paper. (author)

Study of site layout in the Rokkasho site

International Nuclear Information System (INIS)

Sato, Kazuyoshi; Tamura, Kousaku; Yagenji, Akira; Sekiya, Shigeki; Takahashi, Hideo; Neyatani, Yuzuru; Uehara, Masaharu; Motohashi, Keiichi; Hashimoto, Masayoshi; Ogino, Shunji; Nagamatsu, Nobuhide

2006-03-01

The Final Design Report (FDR) of the International Thermonuclear Experimental Reactor (ITER) was published on July 2001 as a summary of the Engineering Design Activity (EDA). After the EDA, site dependent design has been investigated for the invitation of ITER toward Rokkasho Site (Iyasakadai area) in Aomori prefecture. This report describes the results of site layout of major buildings and structures of ITER in the Rokkasho-Site. The data of the ground near the site and the results of site dependent design in Japan were applied to this study. Through this study, the most appropriate site layout has been constructed with satisfaction of following conditions. (1) Bedrock level at the tokamak complex building is relatively high and it can be reduced the cost of excavation and foundation work. (2) Total amount of excavation soil for site preparation is minimized and the flexibility of the layout is ensured with flat ground level. (3) Accessibility of human and equipments, reduction of noise and vibration to the environment can be obtained. Total length of ducts and piping between buildings in site is minimized. (author)

Rocketdyne division annual site environmental report, Santa Susana Field Laboratory and De Soto Site, 1991

Energy Technology Data Exchange (ETDEWEB)

none,

1992-12-03

This annual report discusses environmental monitoring at two manufacturing and test operations sites operated in the Los Angeles area by the Rocketdyne Division of Rockwell International Corporation. These are identified as the Santa Susana Field Laboratory (SSFL) and the De Soto site. These sites have been used for manufacturing, R&D, engineering, and testing in a broad range of technical fields, primarily rocket engine propulsion and nuclear reactor technology. The De Soto site is essentially light industry with some laboratory-scale R&D and has little potential impact on the environment. The SSFL site, because of its large size (2.668 acres), warranted comprehensive monitoring to assure protection of the environment. The purpose of this report is to present information on environmental and effluent monitoring primarily for the regulatory agencies involved in controlling operations with nuclear fuel or nuclear reactors. i.e., the U.S. DOE and the California State Department of Health Services (DHS). Radiologic Health Branch (RHB). For that reason. information concentrates on Area IV at SSFL as this is the site of the former nuclear operations. While the major area of interest is radiological, this report also includes a discussion of nonradiological monitoring at SSFL.

Effluent releases at the TRIGA reactor facility

Energy Technology Data Exchange (ETDEWEB)

Whittemore, W L [General Atomic Co., San Diego, CA (United States)

1974-07-01

The principal effluent from the operating TRIGA reactors in our facility is argon-41. As monitored by a recording gas and particulate stack monitor, the values shown in the table, the Mark III operating 24 hours per day for very long periods produced the largest amount of radioactive argon. The quantity of 23.7 Ci A-41 when diluted by the normal reactor room ventilation system corresponded to 1.45 x 10{sup -6} {mu}Ci/cc. As diluted in the roof stack stream and the reactor building wake, the concentration immediately outside the reactor building was 25% MPC for an unrestricted area. The continued dilution of this effluent resulted in a concentration of a few percent MPC at the site boundary (unrestricted area) 350 meters from the reactor. (author)

Design study of plant system for the fusion experimental reactor (FER)

International Nuclear Information System (INIS)

Iida, Hiromasa; Kuroda, Hideo; Yamada, Masao; Suzuki, Tatsushi; Honda, Tsutomu; Ohmura, Hiroshi; Itoh, Shinichi.

1986-11-01

This report describes design study results of the FER plant system. The purpose of this study is to have an image of the FER plant system as a whole by designing major auxiliary systems, reactor building and maintenance and radwaste desposal systems. The major auxiliary systems include tritium, cooling, evacuation and fueling systems. For these each systems, flowdiagrams are studied and designs of devices and pipings are conducted. In the reactor building design, layout of the above auxiliary systems in the building is studied with careful zoning concept by the radiation level. Structural integrity of the reactor building is also studied including seismic analysis. In the design of the maintenance and radwaste system flowdiagram of failed reactor components is developed and transfer vehicles and buildings are designed. Finally assuming JAERI Naka site as the reactor site layout of the whole FER plant system is developed. (author)

Conceptual design of a large heavy water reactor for US siting

International Nuclear Information System (INIS)

Shapiro, N.L.; Jesick, J.F.; Molin, A.T.; Daniel, J.A.

1979-09-01

Information on the PHWR type reactor is presented concerning design characteristics; fuel management and resource utilization; economic evaluations; safety, licensing, and environmental impact; and commercial introduction

Development of an accident consequence assessment code for evaluating site suitability of light- and heavy-water reactors based on the Korean Technical standards

Energy Technology Data Exchange (ETDEWEB)

Hwang, Won Tae; Jeong, Hae Sung; Jeong, Hyo Joon; Kil, A Reum; Kim, Eun Han; Han, Moon Hee [Nuclear Environment Safety Research Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-12-15

Methodologies for a series of radiological consequence assessments show a distinctive difference according to the design principles of the original nuclear suppliers and their technical standards to be imposed. This is due to the uncertainties of the accidental source term, radionuclide behavior in the environment, and subsequent radiological dose. Both types of PWR and PHWR are operated in Korea. However, technical standards for evaluating atmospheric dispersion have been enacted based on the U.S. NRC's positions regardless of the reactor types. For this reason, it might cause a controversy between the licensor and licensee of a nuclear power plant. It was modelled under the framework of the NRC Regulatory Guide 1.145 for light-water reactors, reflecting the features of heavy-water reactors as specified in the Canadian National Standard and the modelling features in MACCS2, such as atmospheric diffusion coefficient, ground deposition, surface roughness, radioactive plume depletion, and exposure from ground deposition. An integrated accident consequence assessment code, ACCESS (Accident Consequence Assessment Code for Evaluating Site Suitability), was developed by taking into account the unique regulatory positions for reactor types under the framework of the current Korean technical standards. Field tracer experiments and hand calculations have been carried out for validation and verification of the models. The modelling approaches of ACCESS and its features are introduced, and its applicative results for a hypothetical accidental scenario are comprehensively discussed. In an applicative study, the predicted results by the light-water reactor assessment model were higher than those by other models in terms of total doses.

Material test reactor fuel research at the BR2 reactor

Energy Technology Data Exchange (ETDEWEB)

Dyck, Steven Van; Koonen, Edgar; Berghe, Sven van den [Institute for Nuclear Materials Science, SCK-CEN, Boeretang, Mol (Belgium)

2012-03-15

required thermal and hydraulic conditions. The availability of a comprehensive set of post irradiation examination facilities on site complements the versatile BR2 reactor to provide a set of high performance tools for MTR fuel qualification. (author)

Advanced Reactors Around the World

International Nuclear Information System (INIS)

Majumdar, Debu

2003-01-01

At the end of 2002, 441 nuclear power plants were operating around the globe and providing 17% of the world's electricity. Although the rate of population growth has slowed, recent United Nations data suggest that two billion more people will be added to the world by 2050. A special report commissioned by the Intergovernmental Panel on Climate Change estimated that electricity demand would grow almost eight-fold from 2000 to 2050 in a high economic grown scenario and more than double in a low-growth scenario. There is also a global aspiration to keep the environment pristine. Because of these reasons, it is expected that a large number of new nuclear reactors may be operating by 2050. Realization of this has created an impetus for the development of a new generation of reactors in several countries. The goal is to make nuclear power cost-competitive with other resources and to enhance safety to a level that no evacuation outside a plant site would be necessary. It should also generate less waste, prevent materials diversion for weapons production, and be sustainable. This article discusses the status of next-generation reactors under development around the world. Specifically highlighted are efforts related to the Generation IV International Forum (GIF) and its six reactor concepts for research and development: Very High Temperature Reactor (VHTR); Gas-Cooled Fast Reactor (GFR); Supercritical Water-Cooled Reactor (SCWR); Sodium-Cooled Fast Reactor (SFR); Lead-Cooled Fast Reactor (LFR); and Molten Salt Reactor (MSR). Also highlighted are nuclear activities specific to Russia and India

Looking to the future with the Integral Fast Reactor

International Nuclear Information System (INIS)

Till, C.

1985-01-01

During the past two years, scientists from Argonne have developed a design for an advanced breeder reactor with a closed, self-contained fuel cycle. This Integral Fast Reactor (IFR) is a pool-type, sodium-cooled reactor. It uses a new metal-alloy fuel design which overcomes the problem of swelling. The possibility of unauthorised diversion of nuclear fuel, and the need to transport plutonium to and from the site, is overcome by using a pyrometallurgical fuel reprocessing technique in a compact facility that is an integral part of the reactor plant. (author)

Seismic retrofitting of Apsara reactor building

International Nuclear Information System (INIS)

Reddy, G.R.; Parulekar, Y.M.; Sharma, A.; Rao, K.N.; Narasimhan, Rajiv; Srinivas, K.; Basha, S.M.; Thomas, V.S.; Soma Kumar, K.

2006-01-01

Seismic analysis of Apsara Reactor building was carried out and was found not meeting the current seismic requirements. Due to the building not qualifying for seismic loads, a retrofit scheme using elasto-plastic dampers is proposed. Following activities have been performed in this direction: Carried out detailed seismic analysis of Apsara reactor building structure incorporating proposed seismic retrofit. Demonstrating the capability of the retrofitted structure to with stand the earth quake level for Trombay site as per the current standards by analysis and by model studies. Implementation of seismic retrofit program. This paper presents the details of above aspects related to Seismic analysis and retrofitting of Apsara reactor building. (author)

Comparison of the Radionuclides Dispersion at the UAE Barakah Site with that at the ROK Shin-Kori Site - Comparison of the radionuclides dispersion in Barakah site with that in Shin-Kori site

Energy Technology Data Exchange (ETDEWEB)

Kim, Sung-yeop; Lee, Kun Jai; Chang, Soon Heung [Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 (Korea, Republic of); Beeley, Philip A. [Khalifa University of Science, Technology and Research, P.O. Box 127788, Abu Dhabi (United Arab Emirates)

2014-07-01

In order to understand the characteristics of atmospheric dispersion of radionuclides in the desert environment of Barakah site in UAE, comparison research with the results of other environments could be an appropriate way to facilitate it. Shin-Kori site is the proper comparison target because same reactor type of APR1400 with that in Barakah site is under construction. Hypothetical accident scenario was considered and accident source term which had been developed in previous research has been applied as releasing source. After reviewing several computation codes, ADMS5 has been selected as an atmospheric dispersion modeling tool which is installing advanced Gaussian plum model and plentiful options. The climate data of both Barakah and Shin-Kori were acquired and the environments of both sites have been simulated considering wind speed, wind direction, temperature, humidity, ground surface roughness and etc. Near field final human doses on the maps have been schematised regarding statistical meteorological data of both sites and dose conversion factors from the publications of ICRP and federal guidance report of EPA. The results of this research are expected to enhance the understanding about differences between two environments which have same reactor type and to improve the comprehension of desert environment of Barakah site as well. Applying different dose conversion factors to Barakah site considering the desert biosphere could be further study to obtain more accurate results. (authors)

Siting technology of underground nuclear power station

International Nuclear Information System (INIS)

Motojima, M.; Hibino, S.

1989-01-01

For the site of a nuclear power station, it may be possible to select a seaside mountain area, if the condition is suitable to excavate large rock caverns in which a reactor and other equipments are installed. As the case study on the siting technology for an underground nuclear power station, the following example was investigated. The site is a seaside steep mountain area, and almost all the equipments are installed in plural tunnel type caverns. The depth from the ground surface to the top of the reactor cavern is about 150 m, and the thickness of the rock pillar between the reactor cavern of 33 m W x 82 mH x 79 mD and the neighboring turbine cavern is 60 m. In this paper, the stability of rock caverns in this example, evaluated by numerical analysis, is described. The numerical analysis was carried out on the central cross section of the reactor cavern, taking the turbine cavern, geostress, the mechanical properties of rock mass and the process of excavation works in consideration. By the analysis, the underground caverns in this example were evaluated as stable, if the rock quality is equivalent to C H class or better according to the CRIEPI rock classification. (K.I.)

Jules Horowitz reactor (RJH): its design

International Nuclear Information System (INIS)

Dupuy, J.P.

2002-01-01

This article presents the design of the new irradiation facility (Jules Horowitz reactor) that is planned to be built on the Cadarache site of Cea. 2 principles have been followed. The first one is based on a physical separation between the systems and activities related to the reactor and the experiments from one hand and the other systems and means dedicated to the treatment of the experimental devices before and after irradiation on the other hand. This first principle implies to build 2 buildings: the reactor building and the nuclear auxiliaries building. Inside the reactor building activities from the reactor itself are separated from those dedicated to experimentation. In order to maximize the efficiency of such a reactor, an important number of simultaneous experiments is expected, which will generate an endless flux of incoming and out-going experiments and as a consequence an important handling work between the different work posts. The second principle aims at easing any handling work without breaking the rules of confinement. The different storing pools, the water pits that lead to the 5 hot cells and the reactor tank will communicate through a water-filled canal that will link the 2 buildings. (A.C.)

The control of reactor outages

International Nuclear Information System (INIS)

Bouget, Y.H.; Berteloot, J.M.

1995-01-01

The 1985-1992 period was marked by a continuous decay in French reactors operation. This situation has led the Committee for Outages Mastery to take steps for the improvement of nuclear power plants availability. The control of reactor outages requires an integrated vision of the safety, duration, dosimetry, costs and security aspects and a perfect management of contractors. The paper describes the methodology used for the management and the maintenance of the French PWR reactors stock. A detailed schedule of maintenance tasks with dose estimations is now required from each site to anticipate and optimize the duration of outages. Thanks to this action, a significant reduction of the maintenance costs is observed for the 1992-1995 period. (J.S.). 2 figs

Regulatory Issues and Challenges in Preparing for the Regulation of New Reactor Siting: Malaysia's Experience

International Nuclear Information System (INIS)

Jais, Azlina Mohammad; Hassan, Halimah; Yasir, Muhamad Samudi; Roslan, Ridha

2011-01-01

This paper aims at giving an overview about the issues and challenges facing regulatory authority, the Atomic Energy Licensing Board (AELB) in ensuring nuclear safety, security and safeguards (3S's) and other relevant authorities to meet an impending nuclear power programme post-2020, in particular at the beginning stage of preparation for the regulation of nuclear power reactor siting. A comparison with an international framework and guidelines of the International Atomic Energy Agency (IAEA) and other countries' practice was made to get an overview of the present adequacy of Malaysia's nuclear regulatory framework in preparation for Malaysia to consider and perhaps decide for a safe, secure and peaceful nuclear power project in Malaysia, in utilising nuclear power in a quest for energy diversity and security. The important stage in the development of a nuclear power project is the evaluation of a suitable site to establish the site-related design inputs for the NPP. The evaluation of suitable site is the result of a process to ensure adequate protection of workers, public and the environment from the undue risk of ionizing radiation arising from NPP taking into account impact to the social communities and public acceptance, thus it will depend on the regulators to ensure a high level safety standards and security are met, in addition to its peaceful uses. Development of regulatory criteria for the site evaluation is a pre-initiatives licensing work for a possible nuclear power plant to performing effective nuclear safety and security reviews in an efficient and timely manner regardless whether Malaysia embarks on a nuclear power programme with anticipating challenges, learning from others' experiences in preparing for the demands for new licensing processes by collaborating internationally, in an expanding global environment

Containment And Siting Of Nuclear Power Plants. Proceedings Of The Symposium

International Nuclear Information System (INIS)

1967-01-01

Proceedings of a Symposium organized by the IAEA and held in Vienna, 3-7 April 1967. The meeting was attended by 246 participants from 29 countries and 6 international organizations. Contents: National practices in reactor siting (14 papers); Reactor siting considerations (12 papers); Containment for particular reactor types (6 papers); Containment for reactor types - general considerations (6 papers); Release and transport of pollutants (10 papers); Panel discussion. Each paper is in its original language (35 English, 9 French and 4 Spanish) and is preceded by an abstract in English and one in the original language if this is not English. Discussions are in English. (author)

Containment And Siting Of Nuclear Power Plants. Proceedings Of The Symposium

Energy Technology Data Exchange (ETDEWEB)

NONE

1967-09-15

Proceedings of a Symposium organized by the IAEA and held in Vienna, 3-7 April 1967. The meeting was attended by 246 participants from 29 countries and 6 international organizations. Contents: National practices in reactor siting (14 papers); Reactor siting considerations (12 papers); Containment for particular reactor types (6 papers); Containment for reactor types - general considerations (6 papers); Release and transport of pollutants (10 papers); Panel discussion. Each paper is in its original language (35 English, 9 French and 4 Spanish) and is preceded by an abstract in English and one in the original language if this is not English. Discussions are in English. (author)

Definitive design status of the SP-100 Ground Engineering System Test Site

International Nuclear Information System (INIS)

Renkey, E.J. Jr.; Bazinet, G.D.; Bitten, E.J.; Brackenbury, P.J.; Carlson, W.F.; Irwin, J.J.; Edwards, P.A.; Shen, E.J.; Titzler, P.A.

1989-05-01

The SP-100 reactor will be ground tested at the SP-100 Ground Engineering System (GES) Test Site on the US Department of Energy (DOE) Hanford Site near Richland, Washington. Project direction and the flight system design evolution have resulted in a smaller reactor size and the consequential revision to Test Site features to accommodate the design changes and reduce Test Site costs. The significant design events since the completion of the Conceptual Design are discussed in this paper

Definitive design status of the SP-100 Ground Engineering System Test Site

Energy Technology Data Exchange (ETDEWEB)

Renkey, E.J. Jr.; Bazinet, G.D.; Bitten, E.J.; Brackenbury, P.J.; Carlson, W.F.; Irwin, J.J.; Edwards, P.A.; Shen, E.J.; Titzler, P.A.

1989-05-01

The SP-100 reactor will be ground tested at the SP-100 Ground Engineering System (GES) Test Site on the US Department of Energy (DOE) Hanford Site near Richland, Washington. Project direction and the flight system design evolution have resulted in a smaller reactor size and the consequential revision to Test Site features to accommodate the design changes and reduce Test Site costs. The significant design events since the completion of the Conceptual Design are discussed in this paper.

2010 Annual Industrial Wastewater Reuse Report for the Idaho National Laboratory Site's Advanced Test Reactor Complex Cold Waste Pond

International Nuclear Information System (INIS)

Lewis, Mike

2011-01-01

This report describes conditions, as required by the state of Idaho Industrial Wastewater Reuse Permit (LA 000161 01, Modification B), for the wastewater land application site at the Idaho National Laboratory Site's Advanced Test Reactor Complex Cold Waste Pond from November 1, 2009 through October 31, 2010. The report contains the following information: (1) Facility and system description; (2) Permit required effluent monitoring data and loading rates; (3) Groundwater monitoring data; (4) Status of compliance activities; and (5) Discussion of the facility's environmental impacts. During the 2010 permit year, approximately 164 million gallons of wastewater were discharged to the Cold Waste Pond. As shown by the groundwater sampling data, sulfate and total dissolved solids concentrations are highest near the Cold Waste Pond and decrease rapidly as the distance from the Cold Waste Pond increases. Although concentrations of sulfate and total dissolved solids are elevated near the Cold Waste Pond, both parameters were below the Ground Water Quality Rule Secondary Constituent Standards in the down gradient monitoring wells.

Gaseous fuel reactors for power systems

International Nuclear Information System (INIS)

Helmick, H.H.; Schwenk, F.C.

1978-01-01

The Los Alamos Scientific Laboratory is participating in a NASA-sponsored program to demonstrate the feasibility of a gaseous uranium fueled reactor. The work is aimed at acquiring experimental and theoretical information for the design of a prototype plasma core reactor which will test heat removal by optical radiation. The basic goal of this work is for space applications, however, other NASA-sponsored work suggests several attractive applications to help meet earth-bound energy needs. Such potential benefits are small critical mass, on-site fuel processing, high fuel burnup, low fission fragment inventory in reactor core, high temperature for process heat, optical radiation for photochemistry and space power transmission, and high temperature for advanced propulsion systems. Low power reactor experiments using uranium hexafluoride gas as fuel demonstrated performance in accordance with reactor physics predictions. The final phase of experimental activity now in progress is the fabrication and testing of a buffer gas vortex confinement system

Guidelines for nuclear reactor equipments safety-analysis

International Nuclear Information System (INIS)

1978-01-01

The safety analysis in approving the applications for nuclear reactor constructions (or alterations) is performed by the Committee on Examination of Reactor Safety in accordance with various guidelines prescribed by the Atomic Energy Commission. In addition, the above Committee set forth its own regulations for the safety analysis on common problems among various types of nuclear reactors. This book has collected and edited those guidelines and regulations. It has two parts: Part I includes the guidelines issued to date by the Atomic Energy Commission: and Part II - regulations of the Committee. Part I has collected 8 categories of guidelines which relate to following matters: nuclear reactor sites analysis guidelines and standards for their applications; standard exposure dose of plutonium; nuclear ship operation guidelines; safety design analysis guidelines for light-water type, electricity generating nuclear reactor equipments; safety evaluation guidelines for emergency reactor core cooling system of light-water type power reactors; guidelines for exposure dose target values around light-water type electricity generating nuclear reactor equipments, and guidelines for evaluation of above target values; and meteorological guidelines for the safety analysis of electricity generating nuclear reactor equipments. Part II includes regulations of the Committee concerning - the fuel assembly used in boiling-water type and in pressurized-water type reactors; techniques of reactor core heat designs, etc. in boiling-water reactors; and others

Revised reactor accident source terms in the U.S. and implementation for light water reactors

International Nuclear Information System (INIS)

Soffer, L.; Lee, J.Y.

1992-01-01

Current NRC reactor accident source terms used for licensing are contained in Regulatory Guides 1.3 and 1.4 and specify that 100 % of the core inventory of noble gases and 25 % of the iodine fission products are assumed to be instantaneously available for release from the containment. The chemical form of the iodine fission products is also assumed to be predominantly elemental (I 2 ) iodine. These assumptions have strongly affected present nuclear plant designs. Severe accident research results have confirmed that although the current source term is very substantial and has resulted in a very high level of plant capability, the present source term is no longer compatible with a realistic understanding of severe accidents. The NRC has issued a proposed revision of the reactor accident source terms as part of several regulatory activities to incorporate severe accident insights for future plants. A revision to 10 CFR 100 is also being proposed to specify site criteria directly and to eliminate source terms and doses for site evaluation. Reactor source terms will continue to be important in evaluating plant designs. Although intended primarily for future plants, existing and evolutionary power plants may voluntarily apply revised accident source term insights as well in licensing. The proposed revised accident source terms are presented in terms of fission product composition, magnitude, timing and iodine chemical form. Some implications for light water reactors are discussed. (author)

Technology development and demonstration for TRIGA research reactor decontamination, decommissioning and site restoration

International Nuclear Information System (INIS)

Oh, Won Zin; Jung, Ki Jung; Lee, Byung Jik

1997-01-01

This paper describes the introduction to research reactor decommissioning plan at KAERI, the background of technology development and demonstration, and the current status of the system decontamination technology for TRIGA reactors, concrete decontamination and dust treatment technologies, wall ranging robot and graphic simulation of dismantling processes, soil decontamination and restoration technology, recycling or reuse technologies for radioactive metallic wastes, and incineration technology demonstration for combustible wastes. 9 figs

Removal of spent fuel from the TVR reactor for reprocessing and proposals for the RA reactor spent fuel handling

International Nuclear Information System (INIS)

Volkov, E.B.; Konev, V.N.; Shvedov, O.V.; Bulkin, S.Yu; Sokolov, A.V.

2002-01-01

The 2,5 MW heavy-water moderated and cooled research reactor TVR was located at the Moscow Institute for Theoretical and Experimental Physics site. In 1990 the final batch of spent nuclear fuel (SNF) from the TVR reactor was transported for reprocessing to Production Association (PA) 'Mayak'. This transportation of the SNF was a part of TVR reactor decommissioning. The special technology and equipment was developed in order to fulfill the preparation of TVR SNF for transportation. The design of the TVR reactor and the fuel elements used are similar to the design and fuel elements of the RA reactor. Two different ways of RA spent fuel elements for transportation to reprocessing plant are considered: in aluminum barrels, and in additional cans. The experience and equipment used for the preparing TVR fuel elements for transportation can help the staff of RA reactor to find the optimal way for these technical operations. (author)

Who needs a small reactor?

International Nuclear Information System (INIS)

Wood, Janet.

1991-01-01

The opportunities and problems facing small reactors were debated at the Delhi seminar. It was established that these were markets where small reactors, producing heat as well as electricity, might be of use. Small combined heat and power reactors would be more useful in district heating than would large reactors, as their optimum heat production is in line with current district heating schemes. Most process heat requirements are below 900 o C and so may be provided by small nuclear plants. Several areas in electricity supply where small and medium sized reactors could find a market were also identified. Despite good reasons for favouring nuclear plants in these markets, such as no production of carbon dioxide, no need to use expensive oil or other scarce fossil fuels and flexibility, these are, however, disincentives to potential buyers. While serial production would decrease plant costs, the lead plants would bear heavy financial risks. Currently too many options in plant design make it difficult to present the advantages of small reactor technology. Siting reactors near centres of population would be problematical. The disposal of spent fuel and radioactive wastes would create problems in developing or non-nuclear countries. Over and above all these problems, however, was that of public acceptance. Some ways of overcoming these disincentives were discussed. (author)

Reactor safety study. An assessment of accident risks in U.S. commercial nuclear power plants. Appendix VI. Calculation of reactor accident consequences

International Nuclear Information System (INIS)

1975-10-01

Information is presented concerning the radioactive releases from the containment following accidents; radioactive inventory of the reactor core; atmospheric dispersion; reactor sites and meteorological data; radioactive decay and deposition from plumes; finite distance of plume travel; dosimetric models; health effects; demographic data; mitigation of radiation exposure; economic model; and calculated results with consequence model

The reactor 'Am guten Mann'

International Nuclear Information System (INIS)

1979-04-01

The 'Schwarzbuch' (citizens action report) against the mentioned reactor is reporting on site selection, the Harrisburg-accident, a chronological summary of: administrative authorization, licensing procedures, proceedings, inquiries to the Federal Parliament and to the Land Parliament, as well as newspaper articles. (HP) [de

Development of conceptual nuclear design of 10MWt research reactor core

International Nuclear Information System (INIS)

Kim, M. H.; Lim, J. Y.; Win, Naing; Park, J. M.

2008-03-01

KAERI has been devoted to develop export-oriented research reactors for a growing world-wide demand of new research reactor construction. Their ambition is that design of Korean research reactor must be competitive in commercial and technological based on the experience of the HANARO core design concept with thermal power of 30MW. They are developing a new research reactor named Advanced HANARO research Reactor (AHR) with thermal power of 20 MW. KAERI has export records of nuclear technology. In 1954-1967 two series of pool type research reactors based on the Russian design, VVR type and IRT type, have been constructed and commissioned in some countries as well as Russia. Nowadays Russian design is introducing again for export to developing countries such as Union of Myanmar. Therefore the objective of this research is that to build and innovative 10 MW research reactor core design based on the concept of HANARO core design to be competitive with Russian research reactor core design. system tool of HELIOS was used at the first stage in both cases which are research reactor using tubular type fuel assemblies and that reactor using pin type fuel assemblies. The reference core design of first kind of research reactor includes one in-core irradiation site at the core center. The neutron flux evaluations for core as well as reflector region were done through logical consistency of neutron flux distributions for individual assemblies. In order to find the optimum design, the parametric studies were carried out for assembly pitch, active fuel length, number of fuel ring in each assembly and so on. Design result shows the feasibility to have high neutron flux at in-core irradiation site. The second kind of research reactor is used the same kind of assemblies as HANARO and hence there is no optimization about basic design parameters. That core has only difference composition of assemblies and smaller specific power than HANARO. Since it is a reference core at first stage

History of critical experiments at Pajarito Site

International Nuclear Information System (INIS)

Paxton, H.C.

1983-03-01

This account describes critical and subcritical assemblies operated remotely at the Pajarito Canyon Site at the Los Alamos National Laboratory. Earliest assemblies, directed exclusively toward the nuclear weapons program, were for safety tests. Other weapon-related assemblies provided neutronic information to check detailed weapon calculations. Topsy, the first of these critical assemblies, was followed by Lady Godiva, Jezebel, Flattop, and ultimately Big Ten. As reactor programs came to Los Alamos, design studies and mockups were tested at Pajarito Site. For example, nearly all 16 Rover reactors intended for Nevada tests were preceded by zero-power mockups and proof tests at Pajarito Site. Expanded interest and capability led to fast-pulse assemblies, culminating in Godiva IV and Skua, and to the Kinglet and Sheba solution assemblies

History of critical experiments at Pajarito Site

Energy Technology Data Exchange (ETDEWEB)

Paxton, H.C.

1983-03-01

This account describes critical and subcritical assemblies operated remotely at the Pajarito Canyon Site at the Los Alamos National Laboratory. Earliest assemblies, directed exclusively toward the nuclear weapons program, were for safety tests. Other weapon-related assemblies provided neutronic information to check detailed weapon calculations. Topsy, the first of these critical assemblies, was followed by Lady Godiva, Jezebel, Flattop, and ultimately Big Ten. As reactor programs came to Los Alamos, design studies and mockups were tested at Pajarito Site. For example, nearly all 16 Rover reactors intended for Nevada tests were preceded by zero-power mockups and proof tests at Pajarito Site. Expanded interest and capability led to fast-pulse assemblies, culminating in Godiva IV and Skua, and to the Kinglet and Sheba solution assemblies.

Site Restoration

Energy Technology Data Exchange (ETDEWEB)

Noynaert, L.; Bruggeman, A.; Cornelissen, R.; Massaut, V.; Rahier, A

2001-04-01

The objectives, the programme, and the achievements of the Site Restoration Department of SCK-CEN in 2000 are summarised. Main activities include the decommissioning of the BR3 PWR-reactor as well as other clean-up activities, projects on waste minimisation and activities related to the management of decommissioning projects. The department provides consultancy and services to external organisations.

Site Restoration

International Nuclear Information System (INIS)

Noynaert, L.; Bruggeman, A.; Cornelissen, R.; Massaut, V.; Rahier, A.

2001-01-01

The objectives, the programme, and the achievements of the Site Restoration Department of SCK-CEN in 2000 are summarised. Main activities include the decommissioning of the BR3 PWR-reactor as well as other clean-up activities, projects on waste minimisation and activities related to the management of decommissioning projects. The department provides consultancy and services to external organisations

Nuclear reactor safety: on the history of the regulatory process

International Nuclear Information System (INIS)

Okrent, D.

1981-01-01

This manuscript is derived from a long report which examines the history of the evolution of light water reactor safety. The central portion of the document provides a historical view of the development of siting policy and the major safety issues which interacted strongly with siting policy. A very incomplete selection of the very many important issues and developments in light water reactor safety is also included. Coverage of the loss-of-coolant accident (LOCA) has deliberately been abbreviated to include only a few selected aspects

Passive safe small reactor for distributed energy supply system sited in water filled pit at seaside

International Nuclear Information System (INIS)

Ishida, Toshihisa; Imayoshi, Shou

2003-01-01

Japan Atomic Energy Research Institute has developed a Passive Safe Small Reactor for Distributed Energy Supply System (PSRD) concept. The PSRD is an integrated-type PWR with reactor thermal power of 100 to 300 MW aimed at supplying electricity, district heating, etc. In design of the PSRD, high priority is laid on enhancement of safety as well as improvement of economy. Safety is enhanced by the following means: i) Extreme reduction of pipes penetrating the reactor vessel, by limiting to only those of the steam, the feed water and the safety valves, ii) Adoption of the water filled containment and the passive safety systems with fluid driven by natural circulation force, and iii) Adoption of the in-vessel type control rod drive mechanism, accompanying a passive reactor shut-down device. For improvement of economy, simplification of the reactor system and long operation of the core over five years without refueling with low enriched UO 2 fuel rods are achieved. To avoid releasing the radioactive materials to the circumstance even if a hypothetical accident, the containment is submerged in a pit filled with seawater at a seaside. Refueling or maintenance of the reactor can be conducted using an exclusive barge instead of the reactor building. (author)

Research reactors fuel cycle problems and dilemma

International Nuclear Information System (INIS)

Romano, R.

2004-01-01

During last 10 years, some problems appeared in different steps of research reactors fuel cycle. Actually the majority of these reactors have been built in the 60s and these reactors were operated during all this long period in a cycle with steps which were dedicated to this activity. Progressively and for reasons often economical, certain steps of the cycle became more and more difficult to manage due to closing of some specialised workshops in the activities of scraps recycling, irradiated fuel reprocessing, even fuel fabrication. Other steps of the cycle meet or will meet difficulties, in particular supplying of fissile raw material LEU or HEU because this material was mostly produced in enrichment units existing mainly for military reason. Rarefaction of fissile material lead to use more and more enriched uraniums said 'of technical quality', that is to say which come from mixing of varied qualities of enriched material, containing products resulting from reprocessing. Actually, problems of end of fuel cycle are increased, either consisting of intermediary storage on the site of reactor or on specialised sites, or consisting of reprocessing. This brief summary shows most difficulties which are met today by a major part of industrials of the fuel cycle in the exercise of their activities

Ground testing of an SP-100 prototypic reactor

International Nuclear Information System (INIS)

Motwani, K.; Pflasterer, G.R.; Upton, H.; Lazarus, J.D.; Gluck, R.

1988-01-01

SP-100 is a space power system which is being developed by GE to meet future space electrical power requirements. The ground testing of an SP-100 prototypic reactor system will be conducted at the Westinghouse Hanford Company site located at Richland, Washington. The objective of this test is to demonstrate the performance of a full scale prototypic reactor system, including the reactor, control system and flight shield. The ground test system is designed to simulate the flight operating conditions while meeting all the necessary nuclear safety requirements in a gravity environment. The goal of the reactor ground test system is to establish confidence in the design maturity of the SP-100 space reactor power system and resolve the technical issues necessary for the development of a flight mission design

Nuclear reactors and technology in the next stage

International Nuclear Information System (INIS)

Orlov, V.

2000-01-01

Author deals with the perspectives of development of nuclear power. It is possible to create in a fairly short time reactors and fuel technology that would meet the main requirements for large-scale power production, i.e.: (a) to afford a 100-fold reduction in the specific consumption of uranium, by utilizing thousands of tonnes of Pu accumulated in the spent fuel from the reactors of the fl t stage; .to rule out nuclear disasters, by taking advantage of the intrinsic properties and behavior of reactor, coolant, fuel, etc., with the plants made simpler and cheaper; (b) to hit a balance between the radiotoxicity of waste and that of feed uranium, by providing neutron transmutation; (c) to create power reactors and fuel cycle technology that would not afford extraction of weapon-grade materials. To fulfil all these requirements, it is necessary to provide substantial neutron excess in a chain reaction for Pu breeding, to use fuel with an equilibrium composition, to bum actinides and LLFPs. All this can be done only in fast reactors. Fast reactors can also provide fuel for thermal reactors that might still be used for some applications, operating in a Th/U cycle, which is the best option for such facilities. Novel engineering solutions will be necessary: high-density heat-conductive fuel (UPuN), chemically inert high-boiling coolant (Pb), dry reprocessing. These issues have been studied well enough to allow embarking on the development of advanced fast reactors. Minatom institutions are finalizing a detailed design of a demonstration BREST-300 plant, complete with an on-site fuel cycle that will meet the requirements of large-scale nuclear power. Hopefully, construction of this plant at Beloyarsk site with its subsequent trial operation would open a door to the next stage in nuclear power development. (author)

At-reactor storage of spent fuel for life-of-plant

International Nuclear Information System (INIS)

Fuierer, A.A.

1990-01-01

The management of commercial spent fuel is a fairly broad topic beginning with the discharge from a reactor, its storage on-site, its transport from the reactor site to a U.S. Department of Energy (DOE) facility, and its ultimate disposal in a geologic repository. This paper discusses spent-fuel management in the at-reactor phase. There are two basic methods for at-reactor storage of spent fuel. The first is wet storage in a pool, and the second is dry storage external to the plant in some form of cask or vault. Spent-fuel consolidation will impact the utility and the DOE waste system. Some of these impacts have a positive effect and some have a negative effect, and each will vary somewhat for each utility. Spent-fuel consolidation and life-of-plant storage will be an increased burden to utilities but will likely result in significant cost savings to the overall waste management system and by proper integration can result in significant institutional benefits

Fuel Management of WWER-1000 Reactors of Kudankulam Nuclear Power Plant, India

International Nuclear Information System (INIS)

Pandey, Y.; Chauhan, A.

2008-01-01

Two units of WWER-1000 reactors of Russian design are under construction at Kudankulam site in India. These reactors are expected to be commissioned in 2008. The fuel management services for these reactors shall be carried out using Russian Computer codes. This paper includes a brief description of the core, fuel assembly lattice and physics modeling of the lattice and core for these reactors. Presented in this paper are the salient features of the core load pattern designs and fuel performance for 8 operating cycles of these reactors. The paper describes key improvements in the core load pattern designs to enhance the fuel utilization and its thermal behaviour. Presented in the paper are also the on site fuel management strategies with regard to fuel inventory and nuclear material accounting. A computer code for Fuel Inventory and Nuclear Material Accounting (FINMAC) has been developed for this purpose. The code FINMAC takes care of receipt of fresh fuel, flow between various accounting sub areas (ASAs), burnup or production of nuclear isotopes in the reactor cores and discharge from the reactor core. The code generates Material Balance Reports (MBRs) and Composition of Ending Inventory Reports (COEIs) as per the IAEA standards. (authors)

Situation of test and research reactors' spent fuels

International Nuclear Information System (INIS)

Shimizu, Kenichi; Uchiyama, Junzo; Sato, Hiroshi

1996-01-01

The U.S. DOE decided a renewal Off-Site Fuel Policy for stopping to spread a highly enriched uranium which was originally enriched at the U.S., the policy declared that to receive all HEU spent fuels from Test and Research reactors in all the world. In Japan, under bilateral agreement of cooperation between the government of the United States and the government of Japan concerning peaceful uses of nuclear energy, the highly enriched uranium of Test and Research Reactors' fuels was purchased from the U.S. and the fuels had been manufactured in Japan, America, Germany and France. On the other hand, a former president of the U.S. J. Carter proposed that to convert the fuels from HEU to LEU concerning a nonproliferation of nuclear materials in 1978, and Japan absolutely supported this policy. Under this condition, the U.S. stopped to receive the spent fuels from the other countries concerning legal action to the Off-Site Fuels Policy. As a result, the spent fuels are increasing, and to cross to each reactor's storage capacity, and if this policy start, a faced crisis of Test and Research Reactors will be avoided. (author)

Development of fault diagnostic technique using reactor noise analysis

International Nuclear Information System (INIS)

Park, Jin Ho; Kim, J. S.; Oh, I. S.; Ryu, J. S.; Joo, Y. S.; Choi, S.; Yoon, D. B.

1999-04-01

The ultimate goal of this project is to establish the analysis technique to diagnose the integrity of reactor internals using reactor noise. The reactor noise analyses techniques for the PWR and CANDU NPP(Nuclear Power Plants) were established by which the dynamic characteristics of reactor internals and SPND instrumentations could be identified, and the noise database corresponding to each plant(both Korean and foreign one) was constructed and compared. Also the change of dynamic characteristics of the Ulchin 1 and 2 reactor internals were simulated under presumed fault conditions. Additionally portable reactor noise analysis system was developed so that real time noise analysis could directly be able to be performed at plant site. The reactor noise analyses techniques developed and the database obtained from the fault simulation, can be used to establish a knowledge based expert system to diagnose the NPP's abnormal conditions. And the portable reactor noise analysis system may be utilized as a substitute for plant IVMS(Internal Vibration Monitoring System). (author)

Development of fault diagnostic technique using reactor noise analysis

Energy Technology Data Exchange (ETDEWEB)

Park, Jin Ho; Kim, J. S.; Oh, I. S.; Ryu, J. S.; Joo, Y. S.; Choi, S.; Yoon, D. B

1999-04-01

The ultimate goal of this project is to establish the analysis technique to diagnose the integrity of reactor internals using reactor noise. The reactor noise analyses techniques for the PWR and CANDU NPP(Nuclear Power Plants) were established by which the dynamic characteristics of reactor internals and SPND instrumentations could be identified, and the noise database corresponding to each plant(both Korean and foreign one) was constructed and compared. Also the change of dynamic characteristics of the Ulchin 1 and 2 reactor internals were simulated under presumed fault conditions. Additionally portable reactor noise analysis system was developed so that real time noise analysis could directly be able to be performed at plant site. The reactor noise analyses techniques developed and the database obtained from the fault simulation, can be used to establish a knowledge based expert system to diagnose the NPP's abnormal conditions. And the portable reactor noise analysis system may be utilized as a substitute for plant IVMS(Internal Vibration Monitoring System). (author)

Advanced Safeguards Approaches for New Fast Reactors

International Nuclear Information System (INIS)

Durst, Philip C.; Therios, Ike; Bean, Robert; Dougan, A.; Boyer, Brian; Wallace, Rick L.; Ehinger, Michael H.; Kovacic, Don N.; Tolk, K.

2007-01-01

This third report in the series reviews possible safeguards approaches for new fast reactors in general, and the ABR in particular. Fast-neutron spectrum reactors have been used since the early 1960s on an experimental and developmental level, generally with fertile blanket fuels to 'breed' nuclear fuel such as plutonium. Whether the reactor is designed to breed plutonium, or transmute and 'burn' actinides depends mainly on the design of the reactor neutron reflector and the whether the blanket fuel is 'fertile' or suitable for transmutation. However, the safeguards issues are very similar, since they pertain mainly to the receipt, shipment and storage of fresh and spent plutonium and actinide-bearing 'TRU'-fuel. For these reasons, the design of existing fast reactors and details concerning how they have been safeguarded were studied in developing advanced safeguards approaches for the new fast reactors. In this regard, the design of the Experimental Breeder Reactor-II 'EBR-II' at the Idaho National Laboratory (INL) was of interest, because it was designed as a collocated fast reactor with a pyrometallurgical reprocessing and fuel fabrication line--a design option being considered for the ABR. Similarly, the design of the Fast Flux Facility (FFTF) on the Hanford Site was studied, because it was a successful prototype fast reactor that ran for two decades to evaluate fuels and the design for commercial-scale fast reactors

The use of on-site Project Officers by a nuclear regulatory body

International Nuclear Information System (INIS)

Beare, J.W.

1977-01-01

In Canada consideration of applications for licensing nuclear installations is entrusted to the Reactor Safety Advisory Committee within the Atomic Energy Control Board (AECB). The licensing procedure is conducted in three stages (site approval, construction licence, operating licence). In order to control construction and operation of nuclear installations Project Officers are assigned to each particular installation. The policy of AECB is to send these officers on site several months before the reactor reaches criticality; and during reactor operation. This system clearly provides great practical advantages. (NEA) [fr

Back-end of the research reactor fuel cycle

International Nuclear Information System (INIS)

Gruber, Gehard J.

1996-01-01

This paper outlines the status of topics and issues related to: (1) Research Reactor Spent Nuclear Fuel Return to the U.S., including policy, shipments and ports of entry, management sites, fees, storage technologies, contracts, actual shipment, and legal process, (2) UKAEA: MTR Spent Nuclear Fuel Reprocessing, (3) COGEMA: MTR Spent Nuclear Fuel Reprocessing, and (4) Intermediate Storage + Direct Disposal for Research Reactors. (author)

Research reactor support

International Nuclear Information System (INIS)

2005-01-01

Research reactors (RRs) have been used in a wide range of applications including nuclear power development, basic physics research, education and training, medical isotope production, geology, industry and other fields. However, many research reactors are fuelled with High Enriched Uranium (HEU), are underutilized and aging, and have significant quantities of spent fuel. HEU inventories (fresh and spent) pose security risks Unavailability of a high-density-reprocessable fuel hinders conversion and limits back-end options and represents a survival dilemma for many RRs. Improvement of interim spent fuel storage is required at some RRs. Many RRs are under-utilized and/or inadequately funded and need to find users for their services, or permanently shut down and eventually decommission. Reluctance to decommission affect both cost and safety (loss of experienced staff ) and many shut down but not decommissioned RR with fresh and/or spent fuel at the sites invoke serious concern. The IAEA's research reactor support helps to ensure that research reactors can be operated efficiently with fuels and targets of lower proliferation and security concern and that operators have appropriate technology and options to manage RR fuel cycle issues, especially on long term interim storage of spent research reactor fuel. Availability of a high-density-reprocessable fuel would expand and improve back end options. The International Atomic Energy Agency provides assistance to Member States to convert research reactors from High Enriched Uranium fuel and targets (for medical isotope production) to qualified Low Enriched Uranium fuel and targets while maintaining reactor performance levels. The assistance includes provision of handbooks and training in the performance of core conversion studies, advice for the procurement of LEU fuel, and expert services for LEU fuel acceptance. The IAEA further provides technical and administrative support for countries considering repatriation of its

Safety in decommissioning of research reactors

International Nuclear Information System (INIS)

1986-01-01

This Guide covers the technical and administrative considerations relevant to the nuclear aspects of safety in the decommissioning of reactors, as they apply to the reactor and the reactor site. While the treatment, transport and disposal of radioactive wastes arising from decommissioning are important considerations, these aspects are not specifically covered in this Guide. Likewise, other possible issues in decommissioning (e.g. land use and other environmental issues, industrial safety, financial assurance) which are not directly related to radiological safety are also not considered. Generally, decommissioning will be undertaken after planned final shutdown of the reactor. In some cases a reactor may have to be decommissioned following an unplanned or unexpected event of a series or damaging nature occurring during operation. In these cases special procedures for decommissioning may need to be developed, peculiar to the particular circumstances. This Guide could be used as a basis for the development of these procedures although specific consideration of the circumstances which create the need for them is beyond its scope

Safety Evaluation Report: Restart of K-Reactor, Savannah River Site

International Nuclear Information System (INIS)

1991-08-01

In April 1991, the Department of Energy (DOE) issued DOE/DP-0084T, ''Safety Evaluation Report Restart of K-Reactor Savannah River Site.'' The Safety Evaluation Report (SER) documents the results of DOE reviews and evaluations of the programmatic aspects of a large number of issues which need to be satisfactorily addressed before restart. The issues were evaluated for compliance with the restart criteria included in the SER. The results of those evaluations determined that the restart criteria had been satisfied for some of the issues. However, for most of the issues at least part of the applicable restart criteria had not been found to be satisfied a the time the evaluations were prepared. For those issues, open or confirmatory items were identified that required resolution. This document supplements the April 1991 SER. The SER Supplement documents the resolution of several of the open items identified in the SER. Only those issues (sections) for which at least one open item identified in the SER has now been closed are addressed in this Supplement. Additionally, some SER sections had no open items identified. Therefore, this Supplement does not include all sections that were addressed in the SER. If there are any open items remaining to be resolved for the sections included in this Supplement, that is so identified at the end of the section. The resolution of those remaining open times, and all remaining open items for those SER sections not included in this first Supplement, will be documented in future SER Supplements. Resolution of all open items for an issue indicates that its associated restart criteria have been satisfied, and that DOE concludes that the programmatic aspects of the issue have been satisfactorily addressed

Alteration in reactor installations (Unit 1 and 2 reactor facilities) in the Hamaoka Nuclear Power Station of The Chubu Electric Power Co., Inc. (report)

International Nuclear Information System (INIS)

1982-01-01

A report by the Nuclear Safety Commission to the Ministry of International Trade and Industry concerning the alteration in Unit 1 and 2 reactor facilities in the Hamaoka Nuclear Power Station, Chubu Electric Power Co., Inc., was presented. The technical capabilities for the alteration of reactor facilities in Chubu Electric Power Co., Inc., were confirmed to be adequate. The safety of the reactor facilities after the alteration was confirmed to be adequate. The items of examination made for the confirmation of the safety are as follows: reactor core design (nuclear design, mechanical design, mixed reactor core), the analysis of abnormal transients in operation, the analysis of various accidents, the analysis of credible accidents for site evaluation. (Mori, K.)

Special Analysis for the Disposal of the Idaho National Laboratory Unirradiated Light Water Breeder Reactor Rods and Pellets Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

Energy Technology Data Exchange (ETDEWEB)

None

2014-08-31

The purpose of this special analysis (SA) is to determine if the Idaho National Laboratory (INL) Unirradiated Light Water Breeder Reactor (LWBR) Rods and Pellets waste stream (INEL103597TR2, Revision 2) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS). The INL Unirradiated LWBR Rods and Pellets waste stream consists of 24 containers with unirradiated fabricated rods and pellets composed of uranium oxide (UO2) and thorium oxide (ThO2) fuel in zirconium cladding. The INL Unirradiated LWBR Rods and Pellets waste stream requires an SA because the 229Th, 230Th, 232U, 233U, and 234U activity concentrations exceed the Nevada National Security Site (NNSS) Waste Acceptance Criteria (WAC) Action Levels.

Use of the VR-1 ''Vrabec'' training reactor

International Nuclear Information System (INIS)

Matejka, K.; Kolros, A.; Krops, S.; Polach, S.; Sklenka, L.

1994-01-01

An overview is presented of the extent and ways of using the VR-1 training reactor, which is operated by the Faculty of Nuclear Science and Physical Engineering, Czech Technical University in Prague. A list and the characteristics of 16 problems developed for teaching purposes is given, and the 14 faculties and 2 research institutes participating in the teaching activities are listed. The reactor is used in the education and training of nuclear scientists and engineers. The instrumentation, experimental, handling and operating tools, as well as documentation and texts relating to the reactor are described. The following examples of the teaching activities are included: a guided visit to the operating reactor site, reactor dynamics study and delayed neutron measurement, training course, and the basic criticality experiment. Nuclear safety aspects (hypothetical accidents, quality control and system qualification demonstration, safety culture) are stressed during the education. The reactor department is involved in international cooperation projects. (J.B.). 3 refs

Canisters and nonfuel components at commercial nuclear reactors

International Nuclear Information System (INIS)

Gibbard, K.; Thorpe, J.; Moore, R.S.

1995-01-01

The Energy Information Administration of the U.S. Department of Energy (DOE) collects data annually from commercial nuclear power reactors via the Nuclear Fuel Data survey, Form RW-859. Over the past three years, the survey has collected data on the quantities and types of nonfuel components and on the quantities and contents of canisters in storage at reactor sites. This paper focuses on the annual changes in the data, specific implications of these changes, and lessons that should be applied to future revisions of the study. The total number of canisters reported by utilities for each year from 1986 to 1993 is listed. Changes in the quantities of nonfuel components report by General Reactors from 1992 to 1993 are also provided. Comparisons of canister and nonfuel components components data from year to year and from reactor to reactor point out that survey questions on these topics have been interpreted differently by reactor personnel

'Experience with decommissioning of research and test reactors at Argonne National Laboratory'

International Nuclear Information System (INIS)

Bhattacharyya, S.K.; Yule, T.J.; Fellhauer, C.R.; Boing, L.E.

2002-01-01

A large number of research reactors around the world have reached the end of their useful operational life. Many of these are kept in a controlled storage mode awaiting decontamination and decommissioning (D and D). At Argonne National Laboratory located near Chicago in the United States of America, significant experience has been gained in the D and D of research and test reactors. These experiences span the entire range of activities in D and D - from planning and characterization of the facilities to the eventual disposition of all waste. A multifaceted D nd D program has been in progress at the Argonne National Laboratory - East site for nearly a decade. The program consists of three elements: - D and D of nuclear facilities on the site that have reached the end of their useful life; - Development and demonstrations of technologies that help in safe and cost effective D and D; - Presentation of training courses in D and D practices. Nuclear reactor facilities have been constructed and operated at the ANL-E site since the earliest days of nuclear power. As a result, a number of these early reactors reached end-of-life long before reactors on other sites and were ready for D and D earlier. They presented an excellent set of test beds on which D and D practices and technologies could be demonstrated in environments that were similar to commercial reactors, but considerably less hazardous. As shown, four reactor facilities, plutonium contaminated glove boxes and hot cells, a cyclotron facility and assorted other nuclear related facilities have been decommissioned in this program. The overall cost of the program has been modest relative to the cost of comparable projects undertaken both in the U.S. and abroad. The safety record throughout the program was excellent. Complementing the actual operations, a set of D and D technologies are being developed. These include robotic methods of tool handling and operation, chemical and laser decontamination techniques, sensors

Integral fast reactor safety features

International Nuclear Information System (INIS)

Cahalan, J.E.; Kramer, J.M.; Marchaterre, J.F.; Mueller, C.J.; Pedersen, D.R.; Sevy, R.H.; Wade, D.C.; Wei, T.Y.C.

1988-01-01

The integral fast reactor (IFR) is an advanced liquid-metal-cooled reactor concept being developed at Argonne National Laboratory. The two major goals of the IFR development effort are improved economics and enhanced safety. In addition to liquid metal cooling, the principal design features that distinguish the IFR are: a pool-type primary system, and advanced ternary alloy metallic fuel, and an integral fuel cycle with on-site fuel reprocessing and fabrication. This paper focuses on the technical aspects of the improved safety margins available in the IFR concept. This increased level of safety is made possible by the liquid metal (sodium) coolant and pool-type primary system layout, which together facilitate passive decay heat removal, and a sodium-bonded metallic fuel pin design with thermal and neutronic properties that provide passive core responses which control and mitigate the consequences of reactor accidents

A strategy for resolving the research reactor dilemma in the US

International Nuclear Information System (INIS)

Kerr, H.T.

1991-01-01

The steadily declining number of operating research reactors in the US has been characterized as a growing dilemma that could significantly limit future opportunities for research and educational programs. An overview is presented describing the existing inventory of research reactors in the US Projections are given of potential research and other uses for the reactors. The factors which have contributed to the declining population of research reactors are discussed, and a strategy is proposed to identify and preserve those research reactor facilities needed to fulfill future national needs. The proposed strategy will focus on establishment of user-oriented research reactor centers that are affiliated with reactors at universities, national laboratories, and defense sites in the US and, where appropriate, in foreign countries

A method of installing a reactor container

International Nuclear Information System (INIS)

Hayashi, Kenji; Murakawa, Hisao.

1975-01-01

Object: To achieve exact installation of a reactor container at a site. Structure: A pole is set upright at the center of a cylindrical base portion, a plurality of beams are disposed around the pole in a radial fashion to form a cone, a plurality of steel plates are mounted successively around the cone through a ring, and the steel plates are welded to each other to assemble and install a reactor container at the same time. (Kamimura, M.)

Unique differences in applying safety analyses for a graphite moderated, channel reactor

International Nuclear Information System (INIS)

Moffitt, R.L.

1993-06-01

Unlike its predecessors, the N Reactor at the Hanford Site in Washington State was designed to produce electricity for civilian energy use as well as weapons-grade plutonium. This paper describes the major problems associated with applying safety analysis methodologies developed for commercial light water reactors (LWR) to a unique reactor like the N Reactor. The focus of the discussion is on non-applicable LWR safety standards and computer modeling/analytical variances of standards. The approaches used to resolve these problems to develop safety standards and limits for the N Reactor are described

2011 Annual Industrial Wastewater Reuse Report for the Idaho National Laboratory Site's Advanced Test Reactor Complex Cold Waste Pond

International Nuclear Information System (INIS)

Lewis, Mike

2012-01-01

This report describes conditions, as required by the state of Idaho Industrial Wastewater Reuse Permit (LA 000161 01, Modification B), for the wastewater land application site at the Idaho National Laboratory Site's Advanced Test Reactor Complex Cold Waste Pond from November 1, 2010 through October 31, 2011. The report contains the following information: Facility and system description Permit required effluent monitoring data and loading rates Groundwater monitoring data Status of compliance activities Noncompliance and other issues Discussion of the facility's environmental impacts During the 2011 permit year, approximately 166 million gallons of wastewater were discharged to the Cold Waste Pond. This is well below the maximum annual permit limit of 375 million gallons. As shown by the groundwater sampling data, sulfate and total dissolved solids concentrations are highest near the Cold Waste Pond and decrease rapidly as the distance from the Cold Waste Pond increases. Although concentrations of sulfate and total dissolved solids are elevated near the Cold Waste Pond, both parameters were below the Ground Water Quality Rule Secondary Constituent Standards in the down gradient monitoring wells.

MIT pebble bed reactor project

Energy Technology Data Exchange (ETDEWEB)

Kadak, Andrew C. [Massachusetts Institute of Technology, Cambridge (United States)

2007-03-15

The conceptual design of the MIT modular pebble bed reactor is described. This reactor plant is a 250 Mwth, 120 Mwe indirect cycle plant that is designed to be deployed in the near term using demonstrated helium system components. The primary system is a conventional pebble bed reactor with a dynamic central column with an outlet temperature of 900 C providing helium to an intermediate helium to helium heat exchanger (IHX). The outlet of the IHX is input to a three shaft horizontal Brayton Cycle power conversion system. The design constraint used in sizing the plant is based on a factory modularity principle which allows the plant to be assembled 'Lego' style instead of constructed piece by piece. This principle employs space frames which contain the power conversion system that permits the Lego-like modules to be shipped by truck or train to sites. This paper also describes the research that has been conducted at MIT since 1998 on fuel modeling, silver leakage from coated fuel particles, dynamic simulation, MCNP reactor physics modeling and air ingress analysis.

MIT pebble bed reactor project

International Nuclear Information System (INIS)

Kadak, Andrew C.

2007-01-01

The conceptual design of the MIT modular pebble bed reactor is described. This reactor plant is a 250 Mwth, 120 Mwe indirect cycle plant that is designed to be deployed in the near term using demonstrated helium system components. The primary system is a conventional pebble bed reactor with a dynamic central column with an outlet temperature of 900 C providing helium to an intermediate helium to helium heat exchanger (IHX). The outlet of the IHX is input to a three shaft horizontal Brayton Cycle power conversion system. The design constraint used in sizing the plant is based on a factory modularity principle which allows the plant to be assembled 'Lego' style instead of constructed piece by piece. This principle employs space frames which contain the power conversion system that permits the Lego-like modules to be shipped by truck or train to sites. This paper also describes the research that has been conducted at MIT since 1998 on fuel modeling, silver leakage from coated fuel particles, dynamic simulation, MCNP reactor physics modeling and air ingress analysis

Realities of proximity facility siting

International Nuclear Information System (INIS)

DeMott, D.L.

1981-01-01

Numerous commercial nuclear power plant sites have 2 to 3 reactors located together, and a group of Facilities with capabilities for fuel fabrication, a nuclear reactor, a storage area for spent fuel, and a maintenance area for contaminated equipment and radioactive waste storage are being designed and constructed in the US. The proximity of these facilities to each other provides that the ordinary flow of materials remain within a limited area. Interactions between the various facilities include shared resources such as communication, fire protection, security, medical services, transportation, water, electrical, personnel, emergency planning, transport of hazardous material between facilities, and common safety and radiological requirements between facilities. This paper will explore the advantages and disadvantages of multiple facilities at one site. Problem areas are identified, and recommendations for planning and coordination are discussed

Integral fast reactor shows its mettle

International Nuclear Information System (INIS)

Chang, Ya.; Lajnberri, M.; Barris, L.; Uoters, L.

1988-01-01

The main aspects of the problem of developing a closed fuel cycle at a NPP built in the so-called integrated version when a fast reactor and the plant for spent fuel regeneration and fuel element production are located in the same site (IFR project), are considered. The technologies of U-Pu-Zr alloy fuel reprocessing and production based on high-temperature metallurgical process and the method of casting under pressure are described. The demonstration of practical feasibility of the fuel cycle on the basis of the IFR reactor is planned for 1990

Regulatory aspects of nuclear reactor decommissioning

International Nuclear Information System (INIS)

Ross, W.M.

1990-01-01

The paper discusses the regulatory aspects of decommissioning commercial nuclear power stations in the UK. The way in which the relevant legislation has been used for the first time in dealing with the early stages of decommissioning commercial nuclear reactor is described. International requirements and how they infit with the UK system are also covered. The discussion focusses on the changes which have been required, under the Nuclear Site Licence, to ensure that the licensee carries out of work of reactor decommissioning in a safe and controlled manner. (Author)

Tritium instrumentation for a fusion reactor power plant

International Nuclear Information System (INIS)

Shank, K.E.; Easterly, C.E.

1976-09-01

A review of tritium instrumentation is presented. This includes a discussion of currently available in-plant instrumentation and methods required for sampling stacks, monitoring process streams and reactor coolants, analyzing occupational work areas for air and surface contamination, and personnel monitoring. Off-site instrumentation and collection techniques are also presented. Conclusions are made concerning the adequacy of existing instrumentation in relation to the monitoring needs for fusion reactors

Radioiodine in the Savannah River Site environment

Energy Technology Data Exchange (ETDEWEB)

Kantelo, M.V.; Bauer, L.R.; Marter, W.L.; Murphy, C.E. Jr.; Zeigler, C.C.

1993-01-15

Radioiodine, which is the collective term for all radioactive isotopes of the element iodine, is formed at the Savannah River Site (SRS) principally as a by-product of nuclear reactor operations. Part of the radioiodine is released to the environment during reactor and reprocessing operations at the site. The purpose of this report is to provide an introduction to radioiodine production and disposition, its status in the environment, and the radiation dose and health risks as a consequence of its release to the environment around the Savannah River Plant. A rigorous dose reconstruction study is to be completed by thee Center for Disease Control during the 1990s.

Radioiodine in the Savannah River Site environment

International Nuclear Information System (INIS)

Kantelo, M.V.; Bauer, L.R.; Marter, W.L.; Murphy, C.E. Jr.; Zeigler, C.C.

1993-01-01

Radioiodine, which is the collective term for all radioactive isotopes of the element iodine, is formed at the Savannah River Site (SRS) principally as a by-product of nuclear reactor operations. Part of the radioiodine is released to the environment during reactor and reprocessing operations at the site. The purpose of this report is to provide an introduction to radioiodine production and disposition, its status in the environment, and the radiation dose and health risks as a consequence of its release to the environment around the Savannah River Plant. A rigorous dose reconstruction study is to be completed by thee Center for Disease Control during the 1990s

Advanced Safeguards Approaches for New Fast Reactors

Energy Technology Data Exchange (ETDEWEB)

Durst, Philip C.; Therios, Ike; Bean, Robert; Dougan, A.; Boyer, Brian; Wallace, Rick L.; Ehinger, Michael H.; Kovacic, Don N.; Tolk, K.

2007-12-15

This third report in the series reviews possible safeguards approaches for new fast reactors in general, and the ABR in particular. Fast-neutron spectrum reactors have been used since the early 1960s on an experimental and developmental level, generally with fertile blanket fuels to “breed” nuclear fuel such as plutonium. Whether the reactor is designed to breed plutonium, or transmute and “burn” actinides depends mainly on the design of the reactor neutron reflector and the whether the blanket fuel is “fertile” or suitable for transmutation. However, the safeguards issues are very similar, since they pertain mainly to the receipt, shipment and storage of fresh and spent plutonium and actinide-bearing “TRU”-fuel. For these reasons, the design of existing fast reactors and details concerning how they have been safeguarded were studied in developing advanced safeguards approaches for the new fast reactors. In this regard, the design of the Experimental Breeder Reactor-II “EBR-II” at the Idaho National Laboratory (INL) was of interest, because it was designed as a collocated fast reactor with a pyrometallurgical reprocessing and fuel fabrication line – a design option being considered for the ABR. Similarly, the design of the Fast Flux Facility (FFTF) on the Hanford Site was studied, because it was a successful prototype fast reactor that ran for two decades to evaluate fuels and the design for commercial-scale fast reactors.

Regional groundwater flow model for C, K. L. and P reactor areas, Savannah River Site, Aiken, SC

Energy Technology Data Exchange (ETDEWEB)

Flach, G.P.

2000-02-11

A regional groundwater flow model encompassing approximately 100 mi2 surrounding the C, K, L, and P reactor areas has been developed. The reactor flow model is designed to meet the planning objectives outlined in the General Groundwater Strategy for Reactor Area Projects by providing a common framework for analyzing groundwater flow, contaminant migration and remedial alternatives within the Reactor Projects team of the Environmental Restoration Department. The model provides a quantitative understanding of groundwater flow on a regional scale within the near surface aquifers and deeper semi-confined to confined aquifers. The model incorporates historical and current field characterization data up through Spring 1999. Model preprocessing is automated so that future updates and modifications can be performed quickly and efficiently. The CKLP regional reactor model can be used to guide characterization, perform scoping analyses of contaminant transport, and serve as a common base for subsequent finer-scale transport and remedial/feasibility models for each reactor area.

Regional groundwater flow model for C, K. L. and P reactor areas, Savannah River Site, Aiken, SC

International Nuclear Information System (INIS)

Flach, G.P.

2000-01-01

A regional groundwater flow model encompassing approximately 100 mi2 surrounding the C, K, L, and P reactor areas has been developed. The reactor flow model is designed to meet the planning objectives outlined in the General Groundwater Strategy for Reactor Area Projects by providing a common framework for analyzing groundwater flow, contaminant migration and remedial alternatives within the Reactor Projects team of the Environmental Restoration Department. The model provides a quantitative understanding of groundwater flow on a regional scale within the near surface aquifers and deeper semi-confined to confined aquifers. The model incorporates historical and current field characterization data up through Spring 1999. Model preprocessing is automated so that future updates and modifications can be performed quickly and efficiently. The CKLP regional reactor model can be used to guide characterization, perform scoping analyses of contaminant transport, and serve as a common base for subsequent finer-scale transport and remedial/feasibility models for each reactor area

Preliminary Evaluation of Removing Used Nuclear Fuel from Shutdown Sites

Energy Technology Data Exchange (ETDEWEB)

Maheras, Steven J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Best, Ralph E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ross, Steven B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buxton, Kenneth A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); England, Jeffery L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McConnell, Paul E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Massaro, Lawrence M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jensen, Philip J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-09-30

A preliminary evaluation of removing spent nuclear fuel (SNF) from 13 shutdown nuclear power reactor sites was conducted. At these shutdown sites the nuclear power reactors have been permanently shut down and the sites have been decommissioned or are undergoing decommissioning. The shutdown sites were Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, Zion, Crystal River, Kewaunee, San Onofre, and Vermont Yankee. The evaluation was divided into four components: (1) characterization of the SNF and greater-than-Class C low-level radioactive waste (GTCC waste) inventory, (2) a description of the on-site infrastructure and conditions relevant to transportation of SNF and GTCC waste, (3) an evaluation of the near-site transportation infrastructure and experience relevant to shipping transportation casks containing SNF and GTCC waste, including identification of gaps in information, and (4) an evaluation of the actions necessary to prepare for and remove SNF and GTCC waste. Every site was found to have at least one off-site transportation mode option for removing its SNF and GTCC waste; some have multiple options. Experience removing large components during reactor decommissioning provided an important source of information used to identify the transportation mode options for the sites. Especially important in conducting the evaluation were site visits, through which information was obtained that would not have been available otherwise. Extensive photographs taken during the site visits proved to be particularly useful in documenting the current conditions at or near the sites. It is expected that additional site visits will be conducted to add to the information presented in the evaluation.

Research and development studies on the seismic behaviour of the PEC fast reactor

Energy Technology Data Exchange (ETDEWEB)

Martelli, Alessandro [ENEA, Fast Reactor Department, Bologna (Italy); [Bologna University, Faculty of Engineering, Nuclear Engineering Section, Bologna (Italy)

1988-07-01

As introduction to the meeting, this paper provides an overview on the extensive research and development studies performed by ENEA, in co-operation with ANSALDO and ISMES, in the framework of the seismic verification of the Italian PEC fast reactor. The purpose is also to stress the reasons why a wide-ranging experimental programme and detailed numerical analysis, validated on the test results, have been performed for the PEC reactor building and the main vessel. Thus, after some notes on the high levels of the design earthquakes adopted for PEC and the important features of fast reactors in general and PEC as a specific case (making it particularly sensitive to seismic excitations), the paper presents the studies performed for the reactor-block, the core and the shutdown system, summarizing their main features and showing some of the main results. Furthermore, the non-negligible feed-backs of the seismic studies on the reactor-block design are recalled, and the needs of checking seismic design analysis of the main vessel and the reactor building are explained. The on-site experimental programme and the related numerical analysis concerning the main vessel and the reactor building are also shortly described: however, specific papers will present more details on these studies, and will also stress the usefulness of the on-site tests performed on the reactor building for the optimization of the PEC seismic monitoring system. Finally, the Italian lecture invited to this meeting will provide an overview on the state-of-the-art on on-site testing and seismic monitoring in Italy, stressing the perspective of adopting methodologies similar to those used for PEC, for nuclear power plants in general. (author)

Frequency limitations on reactor release derived from radiological criteria

International Nuclear Information System (INIS)

Clarke, R.H.

1976-05-01

Acceptable frequencies are suggested with which a number of defined individual and collective dose criteria are met. This has enabled a relationship to be proposed between the frequency and any event leading to release of radioactive material and the dose commitment to the hypothetical individual at the site boundary. The philosphy developed is generally applicable, but in this instance it has been demonstrated for an SGHW Reactor located at Sizewell. The results are derived on the basis of an acceptable level of risk of fatality to the most exposed individual and the application of the methodology to other reactor types and sites is demonstrated. (author)

On-site treatment of a motorway service area wastewater using a package sequencing batch reactor (SBR).

Science.gov (United States)

Del Solar, J; Hudson, S; Stephenson, T

2005-01-01

A sequencing batch reactor (SBR) treating the effluent of a motorway service station in the south of England situated on a major tourist route was investigated. Wastewater from the kitchens, toilets and washrooms facilities was collected from the areas on each side of the motorway for treatment on-site. The SBR was designed for a population equivalent (p.e.) of 500, assuming an average flow of 100 m3/d, influent biochemical oxygen demand (BOD) of 300 mg/l, and influent suspended solids (SS) of 300 mg/l. Influent monitoring over 8 weeks revealed that the average flow was only 65 m3/d and the average influent BOD and SS were 480 mg/l and 473 mg/l respectively. This corresponded to a high sludge loading rate (F:M) of 0.42 d(-1) which accounted for poor performance. Therefore the cycle times were extended from 6 h to 7 h and effluent BOD improved from 79 to 27 mg/l.

New Production Reactors Program: Report to the Congress by the Secretary of Energy

International Nuclear Information System (INIS)

1990-01-01

In August 1988, DOE issued a report to Congress announcing the Department's proposal for assuring future tritium production capacity through the building of new facilities, specifically, a preferred duality strategy that calls for the design and construction of a new, up-to-date heavy water reactor (HWR) at the Savannah River Site in South Carolina; and, at the same time, to proceed with the design and construction of a modular high-temperature gas-cooled reactor (MHTGR) plant to be located at the Idaho National Engineering Laboratory in Idaho. As a contingency, the Department is developing a light water reactor (LWR) tritium target for possible use in the partially completed WNP-1 reactor located on the Hanford Site, near Richland, Washington. The Secretary created the Office of New Production Reactors (NP) to accomplish the following mission: To provide new production reactor capacity on an urgent schedule for an assured supply of nuclear materials, primarily tritium, to maintain the Nation's nuclear deterrent capability. The organizational philosophy of the Program calls for strong central control with increased safety, environmental, and quality assurance oversight. In addition to separate Engineering Technology Offices for HWR, MHTGR, and LWR that will maintain technical control throughout the life of the Program, the NP Director has created oversight Offices for Safety and Quality and for Environment. An NP Project Management Office will be established at each of the three project sites with the Project Officer reporting directly to the Director of NP. Safety, Quality, and Environmental Field Representatives will be located on-site at the Project Management Offices to serve as a ''resident'' for the Headquarters' Office to whom they will report

Department of Energy's High Flux Isotope Reactor (HFIR), October 20--24, 1980: A special report prepared for the Nuclear Facilities Personnel Qualification and Training Committee: An independent on-site safety review

International Nuclear Information System (INIS)

1981-02-01

The intent of this on-site safety review was to make a broad management assessment of HFIR operations, rather than conduct a detailed in-depth audit. The result of the review should only be considered as having identified trends or indications. The Team's observations and recommendations are based upon licensed reactor facility practices used to meet industry standards. For the most part, these standards form the basis for many of the comments in this report. The Team believes that a uniform minimum standard of performance should be achieved in the operation of DOE reactors. In order to assure that this is accomplished, clear standards are necessary. Consistent with the provisions of past AEC and ERDA policy, the Team has used the standards of the commercial nuclear power industry. It is recognized that this approach is conservative in that the HFIR reactor has a significantly greater degree of inherent safety (low temperature, low pressure, low power) than a licensed reactor

Decommissioning of the Salaspils Research Reactor

Directory of Open Access Journals (Sweden)

Abramenkovs Andris

2011-01-01

Full Text Available In May 1995, the Latvian government decided to shut down the Salaspils Research Reactor and to dispense with nuclear energy in the future. The reactor has been out of operation since July 1998. A conceptual study on the decommissioning of the Salaspils Research Reactor was drawn up by Noell-KRC-Energie- und Umwelttechnik GmbH in 1998-1999. On October 26th, 1999, the Latvian government decided to start the direct dismantling to “green-field” in 2001. The upgrading of the decommissioning and dismantling plan was carried out from 2003-2004, resulting in a change of the primary goal of decommissioning. Collecting and conditioning of “historical” radioactive wastes from different storages outside and inside the reactor hall became the primary goal. All radioactive materials (more than 96 tons were conditioned for disposal in concrete containers at the radioactive wastes depository “Radons” at the Baldone site. Protective and radiation measurement equipment of the personnel was upgraded significantly. All non-radioactive equipment and materials outside the reactor buildings were released for clearance and dismantled for reuse or conventional disposal. Contaminated materials from the reactor hall were collected and removed for clearance measurements on a weekly basis.

Design/licensing of on-site package for core component

International Nuclear Information System (INIS)

Ogasawara, K.; Chohzuka, T.; Shimura, T.; Kikuchi, T.; Fujiwara, R.; Karigome, S.; Takani, M.

1993-01-01

For storage of used core components which are produced from reactors, Tohoku EPCO decided to construct a site bunker at Onagawa site. It was also decided to develop and fabricate one packaging to transport core components from the reactor buildings to the site bunker. The packaging will be used within the power station; therefore, it shall comply with 'The Law for the Business of Electric Power' and relevant Notification. The main requirements of the packaging are as follows: 1) The number of contents, such as channel boxes and control rods, shall be as large as possible. 2) The weight and the outer dimensions of the packaging shall be within the limitation of the reactor building and the site bunker. 3) Materials shall be selected from those which have been already applied for existing packagings and utilized without any problems. 4) It shall be considered during design of trunnions that handling equipment, such as lifting beam, can be used for not only this packaging but also for existing spent fuel packagings. The design of the packaging is completed and has been licensed. The packaging is scheduled to be utilized from November, 1993. (J.P.N.)

REACTOR GROUT THERMAL PROPERTIES

Energy Technology Data Exchange (ETDEWEB)

Steimke, J.; Qureshi, Z.; Restivo, M.; Guerrero, H.

2011-01-28

Savannah River Site has five dormant nuclear production reactors. Long term disposition will require filling some reactor buildings with grout up to ground level. Portland cement based grout will be used to fill the buildings with the exception of some reactor tanks. Some reactor tanks contain significant quantities of aluminum which could react with Portland cement based grout to form hydrogen. Hydrogen production is a safety concern and gas generation could also compromise the structural integrity of the grout pour. Therefore, it was necessary to develop a non-Portland cement grout to fill reactors that contain significant quantities of aluminum. Grouts generate heat when they set, so the potential exists for large temperature increases in a large pour, which could compromise the integrity of the pour. The primary purpose of the testing reported here was to measure heat of hydration, specific heat, thermal conductivity and density of various reactor grouts under consideration so that these properties could be used to model transient heat transfer for different pouring strategies. A secondary purpose was to make qualitative judgments of grout pourability and hardened strength. Some reactor grout formulations were unacceptable because they generated too much heat, or started setting too fast, or required too long to harden or were too weak. The formulation called 102H had the best combination of characteristics. It is a Calcium Alumino-Sulfate grout that contains Ciment Fondu (calcium aluminate cement), Plaster of Paris (calcium sulfate hemihydrate), sand, Class F fly ash, boric acid and small quantities of additives. This composition afforded about ten hours of working time. Heat release began at 12 hours and was complete by 24 hours. The adiabatic temperature rise was 54 C which was within specification. The final product was hard and displayed no visible segregation. The density and maximum particle size were within specification.

Conceptual design study of fusion experimental reactor (FY86 FER)

International Nuclear Information System (INIS)

Saito, Ryusei; Kashihara, Shin-ichiro; Itoh, Shin-ichi

1987-08-01

This report describes the results of conceptual design study on plant systems for the Fusion Experimental Reactor (FY86 FER). Design studies for FER plant systems have been continued from FY85, especially for design modifications made in accordance with revisions of plasma scaling parameters and system improvements. This report describes 1) system construction, 2) site and reactor building plan, 3) repaire and maintenance system, 4) tritium circulation system, 5) heating, ventilation and air conditioning system, 6) tritium clean-up system, 7) cooling and baking system, 8) waste treatment and storage system, 9) control system, 10) electric power system, 11) site factory plan, all of which are a part of FY86 design work. The plant systems described in this report generally have been based on the FY86 FER (ACS Reactor) which is an one of the six candidates for FER. (author)

Reactor safety study. An assessment of accident risks in U. S. commercial nuclear power plants. Appendix VI. Calculation of reactor accident consequences. [PWR and BWR

Energy Technology Data Exchange (ETDEWEB)

1975-10-01

Information is presented concerning the radioactive releases from the containment following accidents; radioactive inventory of the reactor core; atmospheric dispersion; reactor sites and meteorological data; radioactive decay and deposition from plumes; finite distance of plume travel; dosimetric models; health effects; demographic data; mitigation of radiation exposure; economic model; and calculated results with consequence model.

Remaining Sites Verification Package for the 100-F-52, 146-FR Radioecology and Aquatic Biology Laboratory Soil, Waste Site Reclassification Form 2008-022

Energy Technology Data Exchange (ETDEWEB)

J. M. Capron

2008-06-27

The 100-F-52 waste site consisted of the soil under and around the former 146-FR Radioecology and Aquatic Biology Laboratory. The laboratory was used for studies of the effects of pre-reactor and post-reactor process water on fish eggs, young fish, and other small river creatures of interest. In accordance with this evaluation, the confirmatory sampling results support a reclassification of this site to No Action. The current site conditions achieve the remedial action objectives and the corresponding remedial action goals established in the Remaining Sites ROD. The results of confirmatory sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.

Code on the safety of nuclear research reactors: Design

International Nuclear Information System (INIS)

1992-01-01

The main objective of this publication is to provide a safety basis for the design of a research reactor and for the assessment of the design. Another objective is to cover certain aspects related to regulatory supervision, siting and quality assurance, as far as these are related to activities for the design of a research reactor. These objectives are expressed in terms of requirements and recommendations for the design of research reactors. Emphasis is placed on the safety requirements that shall be met rather than on ways in which they can be met. The requirements and recommendations may form the foundation necessary for a Member State to develop specific regulations and safety criteria for its research reactor programme.

Early Site Permit Demonstration Program: Siting Guide, Site selection and evaluation criteria for an early site permit application

International Nuclear Information System (INIS)

1993-01-01

In August 1991, the Joint Contractors came to agreement with Sandia National Laboratories (SNL) and the Department of Energy (DOE) on a workscope for the cost-shared Early Site Permit Demonstration Program. One task within the scope was the development of a guide for site selection criteria and procedures. A generic Siting Guide his been prepared that is a roadmap and tool for applicants to use developing detailed siting plans for their specific region of the country. The guide presents three fundamental principles that, if used, ensure a high degree of success for an ESP applicant. First, the site selection process should take into consideration environmentally diverse site locations within a given region of interest. Second, the process should contain appropriate opportunities for input from the public. Third, the process should be applied so that it is clearly reasonable to an impartial observer, based on appropriately selected criteria, including criteria which demonstrate that the site can host an advanced light water reactor (ALWR). The Siting Guide provides for a systematic, comprehensive site selection process in which three basic types of criteria (exclusionary, avoidance, and suitability) are presented via a four-step procedure. It provides a check list of the criteria for each one of these steps. Criteria are applied qualitatively, as well as presented numerically, within the guide. The applicant should use the generic guide as an exhaustive checklist, customizing the guide to his individual situation

Nuclear technology and reactor safety engineering. The situation ten years after the Chernobyl reactor accident

International Nuclear Information System (INIS)

Birkhofer, A.

1996-01-01

Ten years ago, on April 26, 1986 the most serious accident ever in the history of nuclear tgechnology worldwide happened in unit 4 of the nuclear power plant in Chernobyl in the Ukraine, this accident unveiling to the world at large that the Soviet reactor design lines are bearing unthought of safety engineering deficits. The dimensions of this reactor accident on site, and the radioactive fallout spreading far and wide to many countries in Europe, vividly nourished the concern of great parts of the population in the Western world about the safety of nuclear technology, and re-instigated debates about the risks involved and their justification. Now that ten years have elapsed since the accident, it is appropriate to strike a balance and analyse the situation today. The number of nuclear power plants operating worldwide has been growing in the last few years and this trend will continue, primarily due to developments in Asia. The Chernobyl reactor accident has pushed the international dimension of reactor safety to the foreground. Thus the Western world had reason enough to commit itself to enhancing the engineered safety of reactors in East Europe. The article analyses some of the major developments and activities to date and shows future perspectives. (orig.) [de

Future development of the research nuclear reactor IRT-2000 in Sofia

International Nuclear Information System (INIS)

Apostolov, T.G.

1999-01-01

The present paper presents a short description of the research reactor IRT-2000 Sofia, started in 1961 and operated for 28 years. Some items are considered, connected to the improvements made in the contemporary safety requirements and the unrealized project for modernization to 5 MW. Proposals are considered for reconstruction of reactor site to a 'reactor of low power' for education purposes and as a basis for the country's nuclear technology development. (author)

The advanced MAPLE reactor concept

International Nuclear Information System (INIS)

Lidstone, R.F.; Lee, A.G.; Gillespie, G.E.; Smith, H.J.

1989-01-01

During the past several years, Atomic Energy of Canada Limited (AECL) has been developing the new MAPLE multipurpose reactor concept, which is capable of generating peak thermal neutron fluxes of up to 3 x 10 18 n/m 2 s in its heavy water reflector at a nominal thermal power level of 15MW. An assessment of the MAPLE-D 2 O reactor has shown that it could also be used as a high-flux neutron source. it could be developed to be used for several applications if a 12-site annular core is used. Thermal fluxes several times greater than in existing facilities would be available (author)

Power distribution forecasting device for reactors

International Nuclear Information System (INIS)

Tsukii, Makoto

1981-01-01

Purpose: To save expensive calculations on the forecasting of reactor power distribution. Constitution: Core status (CSD) such as entire coolant flow rate, pressures in the reactor, temperatures at the outlet and inlet and positions for control rods are inputted into a power distribution calculation device to calculate the power distribution based on physical models intermittently. Further, present power distribution is calculated based on in-core neutron flux measured values and CSD in a process control computer. Further, the ratio of the calculation results of the latter to those of the former is calculated, stored and inputted into a correction device to correct the forecast power distribution obtained by the power distribution calculation device. This enables to forecast the power distribution with excellent responsivity in the reactor site. (Furukawa, Y.)

Integral fast reactor safety features

International Nuclear Information System (INIS)

Cahalan, J.E.; Kramer, J.M.; Marchaterre, J.F.; Mueller, C.J.; Pedersen, D.R.; Sevy, R.H.; Wade, D.C.; Wei, T.Y.C.

1988-01-01

The Integral Fast Reactor (IFR) is an advanced liquid-metal-cooled reactor concept being developed at Argonne National Laboratory. The two major goals of the IFR development effort are improved economics and enhanced safety. In addition to liquid metal cooling, the principal design features that distinguish the IFR are: (1) a pool-type primary system, (2) an advanced ternary alloy metallic fuel, and (3) an integral fuel cycle with on-site fuel reprocessing and fabrication. This paper focuses on the technical aspects of the improved safety margins available in the IFR concept. This increased level of safety is made possible by (1) the liquid metal (sodium) coolant and pool-type primary system layout, which together facilitate passive decay heat removal, and (2) a sodium-bonded metallic fuel pin design with thermal and neutronic properties that provide passive core responses which control and mitigate the consequences of reactor accidents

Quantities of actinides in nuclear reactor fuel cycles

International Nuclear Information System (INIS)

Ang, K.P.

1975-01-01

The quantities of plutonium and other fuel actinides have been calculated for equilibrium fuel cycles for 1000 MW reactors of the following types: water reactors fueled with slightly enriched uranium, water reactors fueled with plutonium and natural uranium, fast-breeder reactors, gas-cooled reactors fueled with thorium and highly enriched uranium, and gas-cooled reactors fueled with thorium, plutonium, and recycled uranium. The radioactivity levels of plutonium, americium, and curium processed yearly in these fuel cycles are greatest for the water reactors fueled with natural uranium and recycled plutonium. The total amount of actinides processed is calculated for the predicted future growth of the United States nuclear power industry. For the same total installed nuclear power capacity, the introduction of the plutonium breeder has little effect upon the total amount of plutonium processed in this century. The estimated amount of plutonium in the low-level process wastes in the plutonium fuel cycles is comparable to the amount of plutonium in the high-level fission product wastes. The amount of plutonium processed in the nuclear fuel cycles can be considerably reduced by using gas-cooled reactors to consume plutonium produced in uranium-fueled water reactors. These, and other reactors dedicated for plutonium utilization, could be co-located with facilities for fuel reprocessing and fuel fabrication to eliminate the off-site transport of separated plutonium. (U.S.)

Development of small reactor safety criteria in Canada

International Nuclear Information System (INIS)

Ernst, P.C.; French, P.M.; Axford, D.J.; Snell, V.G.

1990-01-01

A number of new small reactor designs have been proposed in Canada over the last several years and some have reached the stage where licensing discussions have been initiated with the Atomic Energy Control Board (AECB). An inter-organizational Small Reactor Criteria (SRC) working group was formed in 1988 to propose safety and licensing criteria for these small reactors. Two levels of criteria are proposed. The first level forms a safety philosophy and the second is a set of criteria for specific reactor applications. The safety philosophy consists of three basic safety objectives together with evaluation criteria, and fourteen fundamental principles measured by specific criteria, which must be implemented to meet the safety objectives. Two of the fourteen principles are prime: defence in depth, and safety culture; the other twelve principles can be seen as deriving from them. A benefit of this approach is that the concepts of defence in depth and safety culture become well-defined. The objectives and principles are presented in the paper and their criteria are summarized. The second level of criteria, under development, will form a safety application set and will provide small reactor criteria in a number of general areas, such as regulatory process and safety assessment, as well as for specific reactor life-cycle activities, from siting through to decommissioning. The criteria are largely deterministic. However, the frequencies and consequences of postulated accidents are assessed against numerical criteria to assist in judging the acceptability of plant design, operation, and proposed siting. All criteria proposed are designed to be testable in some evidentiary fashion, readily enabling an assessment of compliance for a given proposal

SRP reactor safety evolution

International Nuclear Information System (INIS)

Rankin, D.B.

1984-01-01

The Savannah River Plant reactors have operated for over 100 reactor years without an incident of significant consequence to on or off-site personnel. The reactor safety posture incorporates a conservative, failure-tolerant design; extensive administrative controls carried out through detailed operating and emergency written procedures; and multiple engineered safety systems backed by comprehensive safety analyses, adapting through the years as operating experience, changes in reactor operational modes, equipment modernization, and experience in the nuclear power industry suggested. Independent technical reviews and audits as well as a strong organizational structure also contribute to the defense-in-depth safety posture. A complete review of safety history would discuss all of the above contributors and the interplay of roles. This report, however, is limited to evolution of the engineered safety features and some of the supporting analyses. The discussion of safety history is divided into finite periods of operating history for preservation of historical perspective and ease of understanding by the reader. Programs in progress are also included. The accident at Three Mile Island was assessed for its safety implications to SRP operation. Resulting recommendations and their current status are discussed separately at the end of the report. 16 refs., 3 figs

Tritium Formation and Mitigation in High Temperature Reactors

Energy Technology Data Exchange (ETDEWEB)

Piyush Sabharwall; Carl Stoots

2012-08-01

Tritium is a radiologically active isotope of hydrogen. It is formed in nuclear reactors by neutron absorption and ternary fission events and can subsequently escape into the environment. In order to prevent the tritium contamination of proposed reactor buildings and surrounding sites, this paper examines the root causes and potential solutions for the production of this radionuclide, including materials selection and inert gas sparging. A model is presented that can be used to predict permeation rates of hydrogen through metallic alloys at temperatures from 450–750°C. Results of the diffusion model are presented for one steadystate value of tritium production in the reactor.

Radionuclide trap for liquid metal cooled reactors

International Nuclear Information System (INIS)

McGuire, J.C.; Brehm, W.F.

1978-10-01

At liquid metal cooled reactor operating temperatures, radioactive corrosion product transport and deposition in the primary system will be sufficiently high to limit access time for maintenance of system components. A radionuclide trap has been developed to aid in controlling radioactivity transport. This is a device which is located above the reactor core and which acts as a getter, physically immobilizing radioactive corrosion products, particularly 54 Mn. Nickel is the getter material used. It is most effective at temperatures above 450 0 C and effectiveness increases with increasing temperature. Prototype traps have been tested in sodium loops for 40,000 hours at reactor primary temperatures and sodium velocities. Several possible in-reactor trap sites were considered but a location within the top of each driver assembly was chosen as the most convenient and effective. In this position the trap is changed each time fuel is changed

Proposed fuel cycle for the Integral Fast Reactor

International Nuclear Information System (INIS)

Burris, L.; Walters, L.C.

1985-01-01

One of the key features of ANL's Integral Fast Reactor (IFR) concept is a close-coupled fuel cycle. The proposed fuel cycle is similar to that demonstrated over the first five to six years of operation of EBR-II, when a fuel cycle facility adjacent to EBR-II was operated to reprocess and refabricate rapidly fuel discharged from the EBR-II. Locating the IFR and its fuel cycle facility on the same site makes the IFR a self-contained system. Because the reactor fuel and the uranium blanket are metals, pyrometallurgical processes (shortned to ''pyroprocesses'') have been chosen. The objectives of the IFR processes for the reactor fuel and blanket materials are to (1) recover fissionable materials in high yield; (2) remove fission products adequately from the reactor fuel, e.g., a decontamination factor of 10 to 100; and (3) upgrade the concentration of plutonium in uranium sufficiently to replenish the fissile-material content of the reactor fuel. After the fuel has been reconstituted, new fuel elements will be fabricated for recycle to the reactor

Decontamination and decommissioning techniques for research reactors

International Nuclear Information System (INIS)

Oh, Won Zin; Won, H. J.; Jung, C. H.; Choi, W. K.; Kim, G. N.; Lee, K. W.

2002-05-01

Evaluation of soil decontamination process and the liquid decontamination waste treatment technology are investigation of organic acid as a decontamination agent, investigation of the liquid waste purification process and identification of recycling the decontamination agents. Participation on IAEA CRP meeting are preparation of IAEA technical report on 'studies on decommissioning of TRIGA reactors and site restoration technologies' and exchange the research result, technology, experience and safety regulation of the research reactor D and D of USA, Great Britain, Canada, Belgium, Italy, India and so forth

Development of Advanced Monitoring System with Reactor Neutrino Detection Technique for Verification of Reactor Operations

International Nuclear Information System (INIS)

Furuta, H.; Tadokoro, H.; Imura, A.; Furuta, Y.; Suekane, F.

2010-01-01

Recently, technique of Gadolinium-loaded liquid scintillator (Gd-LS) for reactor neutrino oscillation experiments has attracted attention as a monitor of reactor operation and ''nuclear Gain (GA)'' for IAEA safeguards. When the thermal operation power is known, it is, in principle, possible to non-destructively measure the ratio of Pu/U in reactor fuel under operation from the reactor neutrino flux. An experimental program led by Lawrence Livermore National Laboratory and Sandia National Laboratories in USA has already demonstrated feasibility of the reactor monitoring by neutrinos at San Onofre Nuclear Power Station, and the Pu monitoring by neutrino detection is recognized as a candidate of novel technology to detect undeclared operation of reactor. However, further R and D studies of detector design and materials are still necessary to realize compact and mobile detector for practical use of neutrino detector. Considering the neutrino interaction cross-section and compact detector size, the detector must be set at a short distance (a few tens of meters) from reactor core to accumulate enough statistics for monitoring. In addition, although previous reactor neutrino experiments were performed at underground to reduce cosmic ray muon background, feasibility of the measurement at ground level is required for the monitor considering limited access to the reactor site. Therefore, the detector must be designed to be able to reduce external backgrounds extremely without huge shields at ground level, eg. cosmic ray muons and fast neutrons. We constructed a 0.76 ton Gd-LS detector, and carried out a reactor neutrino measurement at the experimental fast reactor JOYO in 2007. The neutrino detector was set up at 24.3m away from the reactor core at the ground level, and we understood the property of the main background; the cosmic-ray induced fast neutron, well. Based on the experience, we are constructing a new detector for the next experiment. The detector is a Gd

The ultimate safe (US) Reactor: A concept for the third millenium

International Nuclear Information System (INIS)

Gat, U.

1986-01-01

The Ultimate Safe (U.S.) Reactor is based on a novel safety concept. Fission products in the reactor are allowed to accumulate only to a level at which they would constitute a harmless source term. Removal of fission products also removes the decay heat - the driving force for the source term. The reactor has no excess criticality and is controlled by the reactivity temperature coefficient. Safety is inherent and passive. Waste is removed from the site promptly

Future development of the research nuclear reactor IRT-2000 in Sofia

Energy Technology Data Exchange (ETDEWEB)

Apostolov, T.G. [Institute for Nuclear Research and Nuclear Energy, BAS, Sofia (Bulgaria)

1999-07-01

The present paper presents a short description of the research reactor IRT-2000 Sofia, started in 1961 and operated for 28 years. Some items are considered, connected to the improvements made in the contemporary safety requirements and the unrealized project for modernization to 5 MW. Proposals are considered for reconstruction of reactor site to a 'reactor of low power' for education purposes and as a basis for the country's nuclear technology development. (author)

Neutronic calculations of AFPR-100 reactor based on Spherical Cermet Fuel particles

International Nuclear Information System (INIS)

Benchrif, A.; Chetaine, A.; Amsil, H.

2013-01-01

Highlights: • AFPR-100 reactor considered as a small nuclear reactor without on-site refueling originally based on TRISO micro-fuel element. • The AFPR-100 reactor was re-designed using the new Spherical Cermet fuel element. • The adoption of the Cermet fuel instead of TRISO fuel reduces the core lifetime operation by 3.1 equivalent full power years. • We discussed the new micro-fuel element candidate for small and medium sized reactors. - Abstract: The Atoms For Peace Reactor (AFPR-100), as a 100 MW(e) without the need of on-site refueling, was originally based on UO2 TRISO fuel coated particles embedded in a carbon matrix directly cooled by light water. AFPR-100 is considered as a small nuclear reactor without open-vessel refueling which is proposed by Pacific Northwest National Laboratory (PNNL). An account of significant irradiation swelling in the silicon carbide fission product barrier coating layer of TRISO fuel element, a Spherical Cermet Fuel element has been proposed. Indeed, the new fuel concept, which was developed by PNNL, consists of changing the pyro-carbon and ceramic coatings that are incompatible with low temperature by Zirconium. The latter was chosen to avoid any potential Wigner energy effect issues in the TRISO fuel element. Actually, the purpose of this study is to assess the goal of AFPR-100 concept using the Cermet fuel; undeniably, the fuel core lifetime prediction may be extended for reasonably long period without on-site refueling. In fact, we investigated some neutronic parameters of reactor core by the calculation code SRAC95. The results suggest that the core fuel lifetime beyond 12 equivalent full power years (EFPYs) is possible. Hence, the adoption of Cermet fuel concept shows a core lifetime decrease of about 3.1 EFPY

Dismantling method for reactor pressure vessel and system therefor

International Nuclear Information System (INIS)

Hayashi, Makoto; Enomoto, Kunio; Kurosawa, Koichi; Saito, Hideyo.

1994-01-01

Upon dismantling of a reactor pressure vessel, a containment building made of concretes is disposed underground and a spent pressure vessel is contained therein, and incore structures are contained in the spent pressure vessel. Further, a plasma-welder and a pressing machine are disposed to a pool for provisionally placing reactor equipments in the reactor building for devoluming the incore structures by welding and compression. An overhead-running crane and rails therefor are disposed on the roof and the outer side of the reactor building for transporting the pressure vessel from the reactor building to the containment building. They may be contained in the containment building after incorporation of the incore structures into the pressure vessel at the outside of the reactor building. For the devoluming treatment, a combination of cutting, welding, pressing and the like are optically conducted. A nuclear power plant can be installed by using a newly manufactured nuclear reactor, with no requirement for a new site and it is unnecessary to provide a new radioactive waste containing facility. (N.H.)

The research reactor radiation emergency countermeasure system in Korea

International Nuclear Information System (INIS)

Kim, Hee Reyoung; Choi, Geun-Sik; Lee, Wanno; Chung, Kun Ho; Kang, Mun Ja; Lee, Chang-Woo

2010-01-01

A disaster prevention system was established for a radiation emergency from an operation of a research reactor with a thermal power of 30 MW th in Korea. A national radiation disaster countermeasure organization was set up to cope with the radiation emergency classified into three cases whose effective doses were more than 1 mSv/h inside the nuclear facility, inside the site boundary and outside the site boundary. Its role consists of the proclamation and consequent withdrawal of a disaster, a general assessment, an emergency medical service, a field control, radiation protection, resident protection implement, an accident analysis, a security plan, a radiation environmental investigation plan and probe, a radiation environmental effect assessment, and others. The emergency planning zone (EPZ) was settled to be within a radius of 800 m, the average distance between the site boundary and the center of a research reactor in operation, as a quick and effective early countermeasure from the result of the radiation environmental effect assessment. The environmental probing zone was chosen to extend to a radius of 2 km from a research reactor according to the moving path of the radioactive cloud so that a densely populated area could be considered and would be extended to 10 km according to the radiation level of the research reactor and atmospheric diffusion. Practically, the environmental probing is implemented at 22 points inside the site and eight points outside the site considering the geography, population and the wind direction. The gamma radiation dose and atmospheric radioactivity are analyzed during an effluence, and the radioactivity of a ground surface deposit and an environmental sample are analyzed after an effluence. The environmental laboratory covers the analysis of the gamma radioisotopes, tritium, strontium, uranium, gross alpha and beta. It is estimated that the habitability can be recovered when the radiation dose rate is less than 1 mSv/h inside the

Preparations for decommissioning the TRIGA Mark III Berkeley Research Reactor

International Nuclear Information System (INIS)

Denton, Michael M.; Lim, Tek. H.

1988-01-01

On December 20, 1986 the chancellor of UC Berkeley announced his decision to decommission the 20 year old Berkeley Research Reactor citing as principal reasons a decline in use and a need to erect a new computer science building over the reactor's site. In order to meet the University's construction timetable for the new building, the reactor staff together with other units of the campus administration have initiated a program to remove the reactor structure and clear the room for unlicensed use as expediently as possible. Due to the sequence of events which must occur in a limited amount of time, the University adopted a policy to contract out as much of the work as possible, including generation of the defueling and decommissioning plans.The first physical step in the decommissioning project is the removal of the irradiated fuel. This task is largely contracted out to a commercial firm with experience in the transport of radioactive materials and reactor fuel. As suggested by the NRC, the reactor will be defueled under the current operating license. This requires that all fuel must be off-site before the DP can be approved. Therefore any delay in defueling in-turn delays the decommissioning. The NRC has given no commitment or date for completion of their review. Informal discussion with NRC project managers and the experience from other facilities indicate that the review process will take between six and nine months

Decontamination around the site of Chernobylsk; Decontamination autour du site de Tchernobyl

Energy Technology Data Exchange (ETDEWEB)

Manesse, D; Rzepka, J P; Maubert, H

1990-12-01

This report describes the decontamination of the site around the nuclear plant of Chernobylsk after the reactor accident of 1986. The work of decontamination in urban areas, buildings, fields and vegetation are detailed. The interventions to reduce the contamination of surface waters and to protect ground waters are also given. (N.C.).

Penn State advanced light water reactor concept

International Nuclear Information System (INIS)

Borkowski, J.A.; Smith, K.A.; Edwards, R.M.; Robinson, G.E.; Schultz, M.A.; Klevans, E.H.

1987-01-01

The accident at Three Mile Island heightened concerns over the safety of nuclear power. In response to these concerns, a research group at the Pennsylvania State University (Penn State) undertook the conceptual design of an advanced light water reactor (ALWR) under sponsorship of the US Dept. of Energy (DOE). The design builds on the literally hundreds of years worth of experience with light water reactor technology. The concept is a reconfigured pressurized water reactor (PWR) with the capability of being shut down to a safe condition simply by removing all ac power, both off-site and on-site. Using additional passively activated heat sinks and replacing the pressurizer with a pressurizing pump system, the concept essentially eliminates the concerns of core damage associated with a total station blackout. Evaluation of the Penn State ALWR concept has been conducted using the EPRI Modular Modeling System (MMS). Results show that a superior response to normal operating transients can be achieved in comparison to the response with a conventional PWR pressurizer. The DOE-sponsored Penn State ALWR concept has evolved into a significant reconfiguration of a PWR leading to enhanced safety characteristics. The reconfiguration has touched a number of areas in overall plant design including a shutdown turbine in the secondary system, additional passively activated heat sinks, a unique primary side pressurizing concept, a low pressure cleanup system, reactor building layout, and a low power density core design

When reactors reach old age

International Nuclear Information System (INIS)

Fischetti, M.

1986-01-01

While the battle over whether to build new nuclear plants has quieted in recent times, a second struggle is shaping up in the United States as reactors approach a new stage of life: retirement. Four decades into the nuclear power age, questions of how best to dismantle and dispose of a nuclear power plant remain largely unanswered. The debates have been mainly academic until now - although reactors have operated for 25 years, decommissioning retired reactors has simply not been fully planned in this country. But the Shippingport Atomic Power Station in Pennsylvania, the first large-scale power reactor to be retired, is now being decommissioned. The work has rekindled the debates in the light of reality. Outside the United States, decommissioning is also being confronted on a new plane. Virtually all groups involved in decommissioning a reactor in the United States - the utility, the Nuclear Regulatory Commission, the U.S. Department of Energy, the U.S. Environmental Protection Agency, state public service commissions, and citizen organizations - agree that for the most part the technology to dismantle and dispose of a reactor safely is available. They disagree, however, on which technical option is the safest or cheapest and on who should pay for dismantlement. And there are further complications: Which regulations must be complied with. How much radiation exposure for workers and the public is acceptable. Even with answers to these questions, uncertainty about where to dispose of the radioactive waste and about how much residual radiation can be left at a former reactor site plagues the architects of decommissioning. This article discusses these questions

Location analysis and strontium-90 concentrations in deer antlers on the Hanford Site

International Nuclear Information System (INIS)

Tiller, B.L.; Eberhardt, L.E.; Poston, T.M.

1995-05-01

The primary objective of this study was to examine the levels of strontium-90 ( 90 Sr) in deer antlers collected from near previously active reactor sites and distant from the reactor sites along that portion of the Columbia River which borders the Hanford Site. A second objective was to analyze the movements and home-ranges of mule deer residing within these areas and determine to what extent this information contributes to the observed 90 Sr concentrations. 90 Sr is a long-lived radionuclide (29.1 year half life) produced by fission in irradiated fuel in plutonium production reactors on the Hanford Site. It is also a major component of atmospheric fallout from weapons testing. Concentrations of radionuclides found in the developed environment onsite do not pose a health concern to humans or various wildlife routinely monitored. However, elevated levels of radionuclides in found biota may indicate routes of exposure requiring attention

Nuclear safety. Concerns about the nuclear power reactors in Cuba

International Nuclear Information System (INIS)

Wells, Jim; Aloise, Gene; Flaherty, Thomas J.; Fitzgerald, Duane; Zavala, Mario; Hayward, Mary Alice

1992-09-01

In 1976, the Soviet Union and Cuba concluded an agreement to construct two 440-megawatt nuclear power reactors near Cienfuegos on the south central coast of Cuba, about 180 miles south of Key West, Florida. The construction of these reactors, which began around 1983, was a high priority for Cuba because of its heavy dependence on imported oil. Cuba is estimated to need an electrical generation capacity of 3,000 megawatts by the end of the decade. When completed, the first reactor unit would provide a significant percentage (estimated at over 15 percent) of Cuba's need for electricity. It is uncertain when Cuba's nuclear power reactors will become operational. On September 5, 1992, Fidel Castro announced the suspension of construction at both of Cuba's reactors because Cuba could not meet the financial terms set by the Russian government to complete the reactors. Cuban officials had initially planned to start up the first of the two nuclear reactors by the end of 1993. However, before the September 5 announcement, it was estimated that this reactor would not be operational until late 1995 or early 1996. The civil construction (such as floors and walls) of the first reactor is currently estimated to be about 90 percent to 97 percent complete, but only about 37 percent of the reactor equipment (such as pipes, pumps, and motors) has been installed. The civil construction of the second reactor is about 20 percent to 30 percent complete. No information was available about the status of equipment for the second reactor. According to former Cuban nuclear power and electrical engineers and a technician, all of whom worked at the reactor site and have recently emigrated from Cuba, Cuba's nuclear power program suffers from poor construction practices and inadequate training for future reactor operators. One former official has alleged, for example, that the first reactor containment structure, which is designed to prevent the accidental release of radioactive material into

RSK-guidelines for PWR reactors

International Nuclear Information System (INIS)

1979-01-01

The RSK guidelines for PWA reactors of April 24, 1974, have been revised and amended in this edition. The RSK presents a summary of safety requirements to be observed in the design, construction, and operation of PWR reactors in the form of guidelines. From January 1979 onwards these guidelines will be the basis of siting and safety considerations for new PWR reactors, and newly built nuclear power plants will have to form these guidelines. They are not binding for existing nuclear power plants under construction or in operation. It will be a matter of individual discussion whether or not the guidelines will be applied in these plants. The main purpose of the guidelines is to facilitate discussion among RSK members and to give early information on necessary safety requirements. If the guidelines are observed by producers and operators, the RSK will make statements on individual projects at short notice. (orig./HP) [de

Spent fuel management plans for the FiR 1 Reactor

International Nuclear Information System (INIS)

Salmenhaara, S. E. J.

2002-01-01

The FiR 1-reactor, a 250 kW TRIGA reactor, has been in operation since 1962. The main purpose to run the reactor is now the Boron Neutron Capture Therapy (BNCT). The BNCT work dominates the current utilization of the reactor: three days per week for BNCT purposes and only two days per week for other purposes such as the neutron activation analysis and isotope production. The final disposal site is situated in Olkiluoto, on the western coast of Finland. Olkiluoto is also one of the two nuclear power plant sites in Finland. In the new operating license of our reactor there is a special condition. We have to achieve a binding agreement between our Research Centre and either the domestic Nuclear Power Companies about the possibility to use the Olkiluoto final disposal facility for our spent fuel or US DOE about the return of our spent fuel back to USA. If we want to continue the reactor operation beyond the year 2006. the domestic final disposal is the only possibility. At the moment it seems to be reasonable to prepare to both possibilities: the domestic final disposal and the return to the USA offered by US DOE. Because the cost estimates of the both possibilities are on the same order of magnitude, the future of the reactor itself will decide, which of the spent fuel policies will be obeyed. In a couple of years' time it will be seen, if the funding of the reactor and the incomes from the BNCT treatments will cover the costs. If the BNCT and other irradiations develop satisfactorily, the reactor can be kept in operation beyond the year 2006 and the domestic final disposal will be implemented. If, however, there is still lack of money, there is no reason to continue the operation of the reactor and the choice of US DOE alternative is natural. (author)

Prototype fast breeder reactor main options

International Nuclear Information System (INIS)

Bhoje, S.B.; Chellapandi, P.

1996-01-01

Fast reactor programme gets importance in the Indian energy market because of continuous growing demand of electricity and resources limited to only coal and FBR. India started its fast reactor programme with the construction of 40 MWt Fast Breeder Test Reactor (FBTR). The reactor attained its first criticality in October 1985. The reactor power will be raised to 40 MWt in near future. As a logical follow-up of FBTR, it was decided to build a prototype fast breeder reactor, PFBR. Considering significant effects of capital cost and construction period on economy, systematic efforts are made to reduce the same. The number of primary and secondary sodium loops and components have been reduced. Sodium coolant, pool type concept, oxide fuel, 20% CW D9, SS 316 LN and modified 9Cr-1Mo steel (T91) materials have been selected for PFBR. Based on the operating experience, the integrity of the high temperature components including fuel and cost optimization aspects, the plant temperatures are recommended. Steam temperature of 763 K at 16.6 MPa and a single TG of 500 MWe gross output have been decided. PFBR will be located at Kalpakkam site on the coast of Bay of Bengal. The plant life is designed for 30 y and 75% load factor. In this paper the justifications for the main options chosen are given in brief. (author). 2 figs, 2 tabs

Next Generation Reactors in Korea

International Nuclear Information System (INIS)

Oh, Yongshick; Choi, Youngsang; Park, Keecheol

1990-01-01

In Korea, nuclear power will be continuously needed to meet the trend of steady increase in electricity demand. But in relation to the further development of nuclear energy, there are still many uncertainties to be solved such as power demand forecast, site availability, thermal energy utilization and technology enhancement for economic and safety. To cope with those uncertainties effectively and to proceed the nuclear projects uninterruptedly, KEPCO decided to initiate two research project. i. e., one is 'the outlook and developmental strategy of nuclear energy for the early 21st century in the R. O. K' and the other is 'the feasibility study on the advanced reactors in Korea. Prospects of nuclear energy in Korea was overviewed and recommendations from the industry were introduced. It is strong opinion of Korea nuclear industry that nuclear policy should be changed from the support policy to the target management policy. In the point of reactor strategy, the life of light water reactor technology might be longer than expected before in Korea and it is emphasized that good maintenance of light water reactor technology and smooth transition program to the advanced technologies should be carefully considered. There are differences in the opinions between preferences to the evolutionary and/or passive, inherently safe reactors but, in the long-term point of view, it is judged to be desirable to have alternatives

Decommissioning and decontrolling the R1-reactor

International Nuclear Information System (INIS)

Bergman, C.; Holmberg, B.T.

1985-01-01

Sweden's first nuclear reactor - the research reactor R1 - situated in bedrock under the Royal Technical Institute of Stockholm, has in the period 1981-1983 been subject to a complete decommissioning. The National Institute for Radiation Protection has followed the work in detail, and has after the completion of the decommissioning performed measurements of radioactivity on site. The report gives an account of the work the Institute has done in preparation for- and during decommissioning and specifically report on the measurements for classification of the local as free for non-nuclear use. (aa)

L-Reactor operation, Savannah River Plant: environmental assessment

International Nuclear Information System (INIS)

1982-08-01

The purpose of this document is to assess the significance of the effects on the human environment of the proposed resumption of L-reactor operation at the Savannah River Plant, scheduled for October 1983. The discussion is presented under the following section headings: need for resumption of L-Reactor operations and purpose of this environmental assessment; proposed action and alternative; affected environment (including, site location and description, land use, historic and archeological resources, socioeconomic and community characteristics, geology and seismology, hydrology, meteorology and climatology, ecology, and radiation environment); environmental consequences; summary of projected L-Reactor releases and impacts; and Federal and State permits and approval. The three appendices are entitled: radiation dose calculation methods and assumptions; floodplain/wetlands assessment - L-Reactor operations; and, conversion table. A list of references is included at the end of each chapter

Preliminary report about nuclear accident of Chernobylsk reactor

International Nuclear Information System (INIS)

Oliveira, A.R. de.

1986-07-01

The preliminary report of nuclear accident at Chernobyl, in URSS is presented. The Chernobyl site is located geographically and the RBMK type reactors - initials of russian words which mean high power pressure tube reactors are described. The conditions of reactor operation in beginning of accident, the events which lead to reactor destruction, the means to finish the fire, the measurements adopted by Russian in the accident location, the estimative of radioactive wastes, the meteorological conditions during the accident, the victims and medical assistence, the sanitary aspects and consequences for population, the evaluation of radiation doses received at small and medium distance and the estimative of reffered doses by population attained are presented. The official communication of Russian Minister Council and the declaration of IAEA general manager during a collective interview in Moscou are annexed. (M.C.K.) [pt

Development of a new physics data library for the SRS reactors

International Nuclear Information System (INIS)

Niemer, K.A.

1993-01-01

The Savannah River Site (SRS) reactors have historically operated at power levels of -2500 MW; thus, previous reactor physics data libraries were created based on that constant power. However, as a result of recent lower power operation, the existing physics data libraries are no longer adequate. Therefore, a new power-dependent physics library was needed to model the reactor at different power levels. The design and development of a new power-dependent physics data library is discussed in this paper

Early Site Permit Demonstration Program: Siting Guide, Site selection and evaluation criteria for an early site permit application. Revision 1

Energy Technology Data Exchange (ETDEWEB)

1993-03-24

In August 1991, the Joint Contractors came to agreement with Sandia National Laboratories (SNL) and the Department of Energy (DOE) on a workscope for the cost-shared Early Site Permit Demonstration Program. One task within the scope was the development of a guide for site selection criteria and procedures. A generic Siting Guide his been prepared that is a roadmap and tool for applicants to use developing detailed siting plans for their specific region of the country. The guide presents three fundamental principles that, if used, ensure a high degree of success for an ESP applicant. First, the site selection process should take into consideration environmentally diverse site locations within a given region of interest. Second, the process should contain appropriate opportunities for input from the public. Third, the process should be applied so that it is clearly reasonable to an impartial observer, based on appropriately selected criteria, including criteria which demonstrate that the site can host an advanced light water reactor (ALWR). The Siting Guide provides for a systematic, comprehensive site selection process in which three basic types of criteria (exclusionary, avoidance, and suitability) are presented via a four-step procedure. It provides a check list of the criteria for each one of these steps. Criteria are applied qualitatively, as well as presented numerically, within the guide. The applicant should use the generic guide as an exhaustive checklist, customizing the guide to his individual situation.

Hanford/Tomsk reciprocal site visit: Plutonium agreement compliance talks

International Nuclear Information System (INIS)

Libby, R.A.; Sorenson, R.; Six, D.; Schiegel, S.C.

1994-11-01

The objective of the visit to Hanford Site was to: demonstrate equipment, technology, and methods for calculating Pu production, measuring integrated reactor power, and storing and safeguarding PuO 2 ; demonstrate the shutdown of Hanford production reactors; and foster openness and transparency of Hanford operations. The first day's visit was an introduction to Hanford and a review of the history of the reactors. The second day consisted of discussions on the production reactors, reprocessing operations, and PuO 2 storage. The group divided on the third day to tour facilities. Group A toured the N reactor, K-West reactor, K-West Basins, B reactor, and participated in a demonstration and discussion of reactor modeling computer codes. Group B toured the Hanford Pu Storage Facility, 200-East Area, N-cell (oxide loadout station), the Automated Storage Facility, and the Nondestructive Assay Measurement System. Group discussions were held during the last day of the visit, which included scheduling of a US visit to Russia

Remaining Sites Verification Package for the 100-F-52, 146-FR Radioecology and Aquatic Biology Laboratory Soil. Attachment to Waste Site Reclassification Form 2008-022

International Nuclear Information System (INIS)

Capron, J.M.

2008-01-01

The 100-F-52 waste site consisted of the soil under and around the former 146-FR Radioecology and Aquatic Biology Laboratory. The laboratory was used for studies of the effects of pre-reactor and post-reactor process water on fish eggs, young fish, and other small river creatures of interest. In accordance with this evaluation, the confirmatory sampling results support a reclassification of this site to No Action. The current site conditions achieve the remedial action objectives and the corresponding remedial action goals established in the Remaining Sites ROD. The results of confirmatory sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River

A comparison between dispersed nuclear power plants and a nuclear energy center at a hypothetical site on Kentucky Lake, Tennessee. Vol. III. Environmental considerations

International Nuclear Information System (INIS)

Fitzpatrick, F.C.; Gray, D.D.; Hyndman, J.R.; Sisman, O.; Suffern, J.S.; Tyrrell, P.A.; West, D.C.

1976-02-01

The thermal, ecological, and social impacts of a 40-reactor NEC are compared to impacts from four 10-reactor NECs and ten 4-reactor power plants. The comparison was made for surrogate sites in western Tennessee. The surrogate site for the 40-reactor NEC is located on Kentucky Lake. A layout is postulated for ten clusters of four reactors each with 2.5-mile spacing between clusters. The plants use natural-draft cooling towers. A transmission system is proposed for delivering the power (48,000 MW) to five load centers. Comparable transmission systems are proposed for the 10-reactor NECs and the 4-reactor dispersed sites delivering power to the same load centers.

Reactor theory and power reactors. 1. Calculational methods for reactors. 2. Reactor kinetics

International Nuclear Information System (INIS)

Henry, A.F.

1980-01-01

Various methods for calculation of neutron flux in power reactors are discussed. Some mathematical models used to describe transients in nuclear reactors and techniques for the reactor kinetics' relevant equations solution are also presented

TARMS, an on-line boiling water reactor operation management system

International Nuclear Information System (INIS)

Iwamoto, T.; Sakurai, S.; Uematsu, H.; Tsuiki, M.; Makino, K.

1984-01-01

The TARMS (Toshiba Advanced Reactor Management System) software package was developed as an effective on-line, on-site tool for boiling water reactor core operation management. It was designed to support a complete function set to meet the requirement to the current on-line process computers. The functions can be divided into two categories. One is monitoring of the present core power distribution as well as related limiting parameters. The other is aiding site engineers or reactor operators in making the future reactor operating plan. TARMS performs these functions with a three-dimensional BWR core physics simulator LOGOS 2, which is based on modified one-group, coarse-mesh nodal diffusion theory. A method was developed to obtain highly accurate nodal powers by coupling LOGOS 2 calculations with the readings of an in-core neutron flux monitor. A sort of automated machine-learning method also was developed to minimize the errors caused by insufficiency of the physics model adopted in LOGOS 2. In addition to these fundamental calculational methods, a number of core operation planning aid packages were developed and installed in TARMS, which were designed to make the operator's inputs simple and easy. (orig.) [de

Early site reviews for nuclear power facilities: procedures and possible technical review options. Draft

International Nuclear Information System (INIS)

1978-02-01

The document provides guidance for utility companies, State and other governmental agencies, and others who may request or may wish to participate in an early review of site suitability issues related to a site proposed for a nuclear power or test reactor. Although the emphasis of this document is on a nuclear electric generating station, the guidance provided can be used for a test reactor or other kinds of reactors. The procedures to be followed by applicants for construction permits and by others are described and the possible significant areas of technical review are delineated

The U.S. reduced enrichment research and test reactor (RERTR) program

International Nuclear Information System (INIS)

Travelli, A.

1993-01-01

Research and test reactors are widely deployed to study the irradiation behavior of materials of interest in nuclear engineering, to produce radioisotopes for medicine, industry, and agriculture, and as a basic research and teaching tool. In order to maximize neutron flux per unit power and/or to minimize capital costs and fuel cycle costs, most of these reactors were de- signed to utilize uranium with very high enrichment (in the 70% to 95% range). Research reactor fuels with such high uranium enrichment cause a potential risk of nuclear weapons proliferation. Over 140 research and test reactors of significant power (between 10 kW and 250 MW) are in operation with very highly enriched uranium in more than 35 countries, with total power in excess of 1,700 MW. The overall annual fuel requirement of these reactors corresponds to approximately 1,200 kg of 235 U. This highly strategic material is normally exported from the United States, converted to metal form, shipped to a fuel fabricator, and then shipped to the reactor site in finished fuel element form. At the reactor site the fuel is first stored, then irradiated, stored again, and eventually shipped back to the United States for reprocessing. The whole cycle takes approximately four years to complete, bringing the total required fuel inventory to approximately 5,000 kg of 235 U. The resulting international trade in highly-enriched uranium may involve several countries in the process of refueling a single reactor and creates a considerable concern that the highly-enriched uranium may be diverted for non-peaceful purposes while in fabrication, transport, or storage, particularly when it is in the unirradiated form. The proliferation resistance of nuclear fuels used in research and test reactors can be considerably improved by reducing their uranium enrichment to a value less than 20%, but significantly greater than natural to avoid excessive plutonium production

Licensing of MAPLE reactors in Canada

International Nuclear Information System (INIS)

Lee, A.G.; Labrie, J.P.; Langman, V.J.

1999-01-01

Full text: The Operating Licence for a MAPLE reactor (i.e., a 10 MW(th), pool-type reactor), has been approved by the Atomic Energy Control Board (AECB) on August 16th, 1999. This Operating Licence has been obtained within three years of the initiation of the MDS Nordion Medical Isotopes Reactor (MMIR) project, which entails the design, construction and commissioning of two 10 MW MAPLE reactors at AECL's Chalk River Laboratories. The scope and nature of the information required by the AECB, the licensing process and highlights of the events which led to successfully obtaining the Operating Licence for the MAPLE reactor are discussed. These discussions address all phases of the licensing process (i.e., the environmental assessment in support of siting, the Preliminary Safety Analysis Report, PSAR, in support of design, procurement and construction, the Final Safety Analysis Report, FSAR, in support of commissioning and operations, and the development of suitable quality assurance subprograms for each phase). An overview of some of the unique technical aspects associated with the MAPLE reactors, and how they have been addressed during the licensing process are also provided (e.g., applying CSA N285.0, General Requirements for Pressure-Retaining Systems and Components in CANDU Nuclear Power Plants, to a small, low pressure, low temperature research reactor, confirmation of the performance of the driver fuel via laboratory and/or in-reactor testing, validation of the computer codes used to perform the safety analyses, critical parameter uncertainty assessment, full scale hydraulic testing of the performance of the design, fuel handling, human factors validation, operator training and certification). (author)

Reactor core in FBR type reactor

International Nuclear Information System (INIS)

Masumi, Ryoji; Kawashima, Katsuyuki; Kurihara, Kunitoshi.

1989-01-01

In a reactor core in FBR type reactors, a portion of homogenous fuels constituting the homogenous reactor core is replaced with multi-region fuels in which the enrichment degree of fissile materials is lower nearer to the axial center. This enables to condition the composition such that a reactor core having neutron flux distribution either of a homogenous reactor core or a heterogenous reactor core has substantially identical reactivity. Accordingly, in the transfer from the homogenous reactor core to the axially heterogenous reactor core, the average reactivity in the reactor core is substantially equal in each of the cycles. Further, by replacing a portion of the homogenous fuels with a multi-region fuels, thereby increasing the heat generation near the axial center, it is possiable to reduce the linear power output in the regions above and below thereof and, in addition, to improve the thermal margin in the reactor core. (T.M.)

Nuclear energy. The innovations of the N4 reactor

International Nuclear Information System (INIS)

Anon.

1998-01-01

The coupling to the electric network of the two first units of N4 type reactors, on the site of Chooz in the Ardennes, marks the third great step of the French nuclear programme of PWR type reactors, after the realization of 34 units of 900 MWe and 20 units of 1300 M We. The nuclear boiler N4, realizes a new evolution in power, in performances and in reliability. (N.C.)

Location analysis and strontium-90 concentrations in deer antlers on the Hanford Site

Energy Technology Data Exchange (ETDEWEB)

Tiller, B L; Eberhardt, L E; Poston, T M

1995-05-01

The primary objective of this study was to examine the levels of strontium-90 ({sup 90}Sr) in deer antlers collected from near previously active reactor sites and distant from the reactor sites along that portion of the Columbia River which borders the Hanford Site. A second objective was to analyze the movements and home-ranges of mule deer residing within these areas and determine to what extent this information contributes to the observed {sup 90}Sr concentrations. {sup 90}Sr is a long-lived radionuclide (29.1 year half life) produced by fission in irradiated fuel in plutonium production reactors on the Hanford Site. It is also a major component of atmospheric fallout from weapons testing. Concentrations of radionuclides found in the developed environment onsite do not pose a health concern to humans or various wildlife routinely monitored. However, elevated levels of radionuclides in found biota may indicate routes of exposure requiring attention.

Analysis of radiation safety for Small Modular Reactor (SMR) on PWR-100 MWe type

Science.gov (United States)

Udiyani, P. M.; Husnayani, I.; Deswandri; Sunaryo, G. R.

2018-02-01

Indonesia as an archipelago country, including big, medium and small islands is suitable to construction of Small Medium/Modular reactors. Preliminary technology assessment on various SMR has been started, indeed the SMR is grouped into Light Water Reactor, Gas Cooled Reactor, and Solid Cooled Reactor and from its site it is group into Land Based reactor and Water Based Reactor. Fukushima accident made people doubt about the safety of Nuclear Power Plant (NPP), which impact on the public perception of the safety of nuclear power plants. The paper will describe the assessment of safety and radiation consequences on site for normal operation and Design Basis Accident postulation of SMR based on PWR-100 MWe in Bangka Island. Consequences of radiation for normal operation simulated for 3 units SMR. The source term was generated from an inventory by using ORIGEN-2 software and the consequence of routine calculated by PC-Cream and accident by PC Cosyma. The adopted methodology used was based on site-specific meteorological and spatial data. According to calculation by PC-CREAM 08 computer code, the highest individual dose in site area for adults is 5.34E-02 mSv/y in ESE direction within 1 km distance from stack. The result of calculation is that doses on public for normal operation below 1mSv/y. The calculation result from PC Cosyma, the highest individual dose is 1.92.E+00 mSv in ESE direction within 1km distance from stack. The total collective dose (all pathway) is 3.39E-01 manSv, with dominant supporting from cloud pathway. Results show that there are no evacuation countermeasure will be taken based on the regulation of emergency.

Concerning modification of plan for installation of reactors (addition of No.4 reactor and modification of No.1, No.2 and No.3 reactor facilities) at Hamaoka nuclear power plant of Chubu Electric Power Co., Ltd. (reply to inquiry)

International Nuclear Information System (INIS)

1988-01-01

The Nuclear Safety Commission on Oct. 22, 1987 directed the Nuclear Reactor Safety Expert Group to carry out a study on it, made deliberations after receiving a report from the Group on Jun. 28, and submitted the findings to the Minister of International Trade and Industry on Jul. 14. The study and deliberations were intended to determine the conformity of the modifications to the applicable laws relating to control of nuclear material, nuclear fuel and nuclear reactor. The investigation on the location covered the site conditions, geology, seismic environment, meteorology, hydrology, and social environment. The investigations on the safety design of the reactor facilities addressed the design of the overall reactor facilities, anti-earthquake design, and design of other equipment including reactor core, fuel equipment, monitors, reactivity controllers, safety protection equipment, and emergency core cooler. Other investigations included exposure evaluation and accident analysis. It was concluded that the modifications would not have adverse effects on the safety of the reactor facilities. (Nogami, K.)

An alternative proposal for the disposal of potentially contaminated railroad crossties at the Savannah River Site. Revision 1

International Nuclear Information System (INIS)

Hochel, R.C.

1996-06-01

The Savannah River Site (SRS) has accumulated approximately 300,000 crossties that have been replaced over a 40-year period of maintaining the site's 62 miles of railroad track. The ties reside in a pile on an open area of 2.3 acres near the site's F-Area facilities. A small fraction of the ties are potentially contaminated with radioactivity as a result of past site practices and service. Contamination was possible from occasional leaks in transport-casks moved by rail from the site's five nuclear materials production reactors to its two reprocessing facilities. Casks typically were filled with spent fuel, targets, and water from the reactor disassembly basins, which contained small amounts of fission and neutron activation product radioactivity normal to the operation of nuclear reactors

Hydrogeological and Groundwater Flow Model for C, K, L, and P Reactor Areas, Savannah River Site, Aiken, South Carolina

International Nuclear Information System (INIS)

Flach, G.P.

1999-01-01

A regional groundwater flow model encompassing approximately 100 mi 2 surrounding the C, K. L. and P reactor areas has been developed. The Reactor flow model is designed to meet the planning objectives outlined in the General Groundwater Strategy for Reactor Area Projects by providing a common framework for analyzing groundwater flow, contaminant migration and remedial alternatives within the Reactor Projects team of the Environmental Restoration Department

Preliminary Study of Potential Market for Small Reactors

International Nuclear Information System (INIS)

Minato, A.; Brown, N. W.

2008-01-01

Small reactors are an energy supply for a specific purpose and oriented for a different market than large reactors. Small reactors will provide a local solution for developed and developing countries, such as, in remote areas, on small grids, or for non-electricity applications such as, district heating, seawater desalination and process heat. Single or medium sized power stations with small reactors should be compared with single fissile or renewable energy source and not be compared with large reactors. CRIEPI and LLNL have studied the business opportunities for small reactors. The small reactor concept is planned for initial use in small remote communities and in developing countries with small power distribution grid. Rapid installation and simple operation of the small plants is intended to support use in these communities without requiring development of a substantial nuclear technology infrastructure. In this study, two approaches were used in the assessment of the potential market. The first approach took a global look at the need for small nuclear plants. Then selected countries and sites were identified based on countries expressing interest in small reactors to the IAEA and consideration of sites in the US and Japan. (1) Tunisia, Mexico, Indonesia, Uruguay, Egypt and Argentina have demonstrated interest in nuclear power. Selecting one of these is dependent on political and socioeconomic factors, some of which have been identified, that require direct interaction with the countries to establish if they represent real opportunities. (2) The states of Hawaii and Alaska in the United States have high power cost and remote or island communities that may benefit from small nuclear plants. Alaska has shown greater interest in power alternatives including small than Hawaii and there is clearly less public resistance to nuclear power in Alaska. (3) The countries in Central America are actively expanding their power grids but have not demonstrated great interest

The organization of research reactor safety in the UKAEA

International Nuclear Information System (INIS)

Redpath, W.

1983-01-01

The present state of organization and development of research reactor safety in the UKAEA are outlined by addressing the fundamental safety principles which have been adopted in keeping with national health and safety requirement. The organisation, assessment and monitoring of research reactor safety on complex multi-discipline and multi-activity nuclear research and development site are discussed. Methods of safety assessment, such as probabilistic risk assessment and risk acceptance criteria, which have been developed and applied in practice are explained, and some indication of the directions in which some of the current developments in the safety of UKAEA research reactors is also included. (A.J.)

Project management plan for the 105-C Reactor interim safe storage project. Revision 1

International Nuclear Information System (INIS)

Miller, R.L.

1997-01-01

In 1942, the Hanford Site was commissioned by the US Government to produce plutonium. Between 1942 and 1955, eight water-cooled, graphite-moderated reactors were constructed along the Columbia River at the Hanford Site to support the production of plutonium. The reactors were deactivated from 1964 to 1971 and declared surplus. The Surplus Production Reactor Decommissioning Project (BHI 1994b) will decommission these reactors and has selected the 105-C Reactor to be used as a demonstration project for interim safe storage at the present location and final disposition of the entire reactor core in the 200 West Area. This project will result in lower costs, accelerated schedules, reduced worker exposure, and provide direct benefit to the US Department of Energy for decommissioning projects complex wide. This project sets forth plans, organizational responsibilities, control systems, and procedures to manage the execution of the Project Management Plan for the 105-C Reactor Interim Safe Storage Project (Project Management Plan) activities to meet programmatic requirements within authorized funding and approved schedules. The Project Management Plan is organized following the guidelines provided by US Department of Energy Order 4700.1, Project Management System and the Richland Environmental Restoration Project Plan (DOE-RL 1992b)

Nordic study on reactor waste

International Nuclear Information System (INIS)

1981-08-01

In 1981, 14 nuclear power reactors are in operation and 2 under construction in the Nordic countries. So far, the reactor waste originating from day-to-day operation of these plants has been stored in solidified form at the reactor sites. Within a few years a satisfactory disposal procedure needs to be established. While the main R and D effects in the waste field have earlier been devoted to the question of irradiated fuel and waste from reprocessing, there is therefore now an increased interest in reactor waste with its much lower radioactivity but somewhat larger volumes. Since 1977, efforts have been made in a joint Nordic study to examine which facts need to be known in order to perform a comprehensive safety assessment of a reactor waste management system. In the present study a Reference system related to the waste generated over 30 years from six 500 MW-reactors is examined. The dominating radionuclides during storage and transportation accident scenarios are Cs-134, Cs-137 and Co-60. For most of the release scenarios from repositories Cs-137 and Sr-90 are dominating. Some scenarios are, however, dominated by the very longlived nuclides I-129 and C-14. A closer examination of the concentration in the waste of these nuclides and of their leaching properties indicates that their small - but significant - influence, as calculated, is probably grossly overestimated. The mechanical stability obtained in routine solidification processes of reactor waste products in conjunction with the outer container (steel drum, transport container, etc.) turns out to be sufficient. Difficulties were encountered in applying ICRP methodology and available dose calculation methods to calculation of population doses due to small activity releases, and effects extending into the far future. (EG)

A novel approach to the production of medical radioisotopes: the homogeneous SLOWPOKE reactor

International Nuclear Information System (INIS)

Bonin, H.W.; Hilborn, J.W.; Carlin, G.E.; Gagnon, R.; Busatta, P.

2015-01-01

In 2009, the unexpected 15-month outage of the Canadian NRU nuclear reactor resulted in a sudden 30% world shortage, with higher shortages experienced in North America than in Europe. Commercial radioisotope production is from just eight nuclear reactors, most being aging systems near the end of their service life. This paper proposes a more efficient production and distribution model. Tc-99m unit doses would be distributed to regional hospitals from ten integrated 'industrial radiopharmacies', located at existing licensed nuclear reactor sites in North America. At each site, one or more 20 kW Homogeneous SLOWPOKE nuclear reactors would deliver 15 litres of irradiated aqueous uranyl sulfate fuel solution daily to industrial-scale hot cells, for extraction of Mo-99; and the low-enriched uranium would be recycled. Purified Mo-99 would be incorporated in large Mo-99/Tc-99m generators for extraction of Tc-99m five days a week; and each automated hot-cell facility would be designed to load up to 7,000 Tc-99m syringes daily for road delivery to all of the nuclear medicine hospitals within a 3-hour range. At the current price of $20 per unit dose, the annual gross income from 10 sites would be approximately $360 million. The Homogeneous SLOWPOKE reactor evolved from the inherently safe SLOWPOKE-2 research reactor, with a double goal: replacing the heterogeneous SLOWPOKE-2 reactors at the end-of-core life, enabling them to continue their primary missions of research and education, together with full time commercial radioisotope production. The Homogeneous SLOWPOKE reactor was modelled using both deterministic and probabilistic reactor simulation codes. The homogeneous fuel mixture is a dilute aqueous solution of low-enriched uranyl sulfate containing approximately 1 kg of U-235. The reactor is controlled by mechanical absorber rods in the beryllium reflector. Safety analysis was carried out for both normal operation and transient conditions. The most severe

A novel approach to the production of medical radioisotopes: the homogeneous SLOWPOKE reactor

Energy Technology Data Exchange (ETDEWEB)

Bonin, H.W., E-mail: bonin-h@rmc.ca [Royal Military College of Canada, Kingston, Ontario (Canada); Hilborn, J.W. [retired, Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Carlin, G.E. [Ontario Power Generation, Toronto, Ontario (Canada); Gagnon, R.; Busatta, P. [Royal Canadian Navy, Ottawa, Ontario (Canada)

2015-03-15

In 2009, the unexpected 15-month outage of the Canadian NRU nuclear reactor resulted in a sudden 30% world shortage, with higher shortages experienced in North America than in Europe. Commercial radioisotope production is from just eight nuclear reactors, most being aging systems near the end of their service life. This paper proposes a more efficient production and distribution model. Tc-99m unit doses would be distributed to regional hospitals from ten integrated 'industrial radiopharmacies', located at existing licensed nuclear reactor sites in North America. At each site, one or more 20 kW Homogeneous SLOWPOKE nuclear reactors would deliver 15 litres of irradiated aqueous uranyl sulfate fuel solution daily to industrial-scale hot cells, for extraction of Mo-99; and the low-enriched uranium would be recycled. Purified Mo-99 would be incorporated in large Mo-99/Tc-99m generators for extraction of Tc-99m five days a week; and each automated hot-cell facility would be designed to load up to 7,000 Tc-99m syringes daily for road delivery to all of the nuclear medicine hospitals within a 3-hour range. At the current price of $20 per unit dose, the annual gross income from 10 sites would be approximately $360 million. The Homogeneous SLOWPOKE reactor evolved from the inherently safe SLOWPOKE-2 research reactor, with a double goal: replacing the heterogeneous SLOWPOKE-2 reactors at the end-of-core life, enabling them to continue their primary missions of research and education, together with full time commercial radioisotope production. The Homogeneous SLOWPOKE reactor was modelled using both deterministic and probabilistic reactor simulation codes. The homogeneous fuel mixture is a dilute aqueous solution of low-enriched uranyl sulfate containing approximately 1 kg of U-235. The reactor is controlled by mechanical absorber rods in the beryllium reflector. Safety analysis was carried out for both normal operation and transient conditions. The most severe

Socioeconomic consequences of nuclear reactor accidents

International Nuclear Information System (INIS)

Tawil, J.J.; Callaway, J.W.; Coles, B.L.; Cronin, F.J.; Currie, J.W.; Imhoff, K.L.; Lewis, P.M.; Nesse, R.J.; Strenge, D.L.

1984-06-01

This report identifies and characterizes the off-site socioeconomic consequences that would likely result from a severe radiological accident at a nuclear power plant. The types of impacts that are addressed include economic impacts, health impacts, social/psychological impacts and institutional impacts. These impacts are identified for each of several phases of a reactor accident - from the warning phase through the post-resettlement phase. The relative importance of the impact during each accident phase and the degree to which the impact can be predicted are indicated. The report also examines the methods that are currently used for assessing nuclear reactor accidents, including development of accident scenarios and the estimating of socioeconomic accident consequences with various models. Finally, a critical evaluation is made regarding the use of impact analyses in estimating the contribution of socioeconomic consequences to nuclear accident reactor accident risk. 116 references, 7 figures, 15 tables

Screening and identification of sites for a proposed Monitored Retrievable Storage Facility

International Nuclear Information System (INIS)

1985-04-01

The Director, Office of Civilian Radioactive Waste Management (OCRWM), Department of Energy (DOE), has identified the Clinch River Breeder Reactor site, the DOE Oak Ridge Reservation and the Tennessee Valley Authority (TVA) Hartsville Nuclear Plant site as preferred and alternative sites, respectively, for development of site-specific designs as part of the proposal for construction of an integrated Monitored Retrievable Storage (MRS) Facility. The proposal, developed pursuant to Section 141 (b) of the Nuclear Waste Policy Act of 1982, will be submitted to Congress in January 1986. The Director expects to propose to Congress that an MRS be constructed at the perferred site. His judgment could change based on information to be developed between now and January 1986. The decision to construct an MRS facility and final site selection are reserved by Congress for itself. The Director's judgment is based on the results of a rigorous site screening and evaluation process described in this report. The three sites were selected from among eleven sites evaluated in detail. The Clinch River Breeder Reactor site, owned by the Tennessee Valley Authority, was identified as the preferred site. It has several particularly desirable features including: (1) federal ownership and control by the Department of Energy; (2) particularly good transportation access (five miles to the nearest interstate highway and direct rail access); (3) site characteristics and current data base judged by the NRC in 1983 as sufficient for granting a limited work authorization for the now cancelled breeder reactor; and (4) a technical community in the vicinity of site which can provide experienced nuclear facility support functions. 6 figs., 2 tabs

Concept and designs of new-generation fast reactors

International Nuclear Information System (INIS)

Mitenkov, F.M.

1993-01-01

This article discusses the general safety requirements and characteristics for future nuclear power plants. It examines various designs - loop, block, and integrated layouts for reactors. Specifically, the article focuses an integrated design for sodium-cooled fast reactors noting that the BN-600 reactor has operated accident-free over the past 12 years. An obvious advantage of this scheme is that the coolant of the primary loop is localized in one volume (in a vessel), there are no short connections and large-diameter pipes, which of course sharply reduces the probability in coolant leaks. With an integrated scheme the problem of embrittlement of the reactor vessel by neutron irradiation is obviated. The neutron fluence for the vessels of the AST-500 and VPBER-600 reactors, built with an integrated scheme, is less than 10 17 cm -2 . Such a fluence does not cause any appreciable change in the mechanical properties of the vessel steel. The integrated layout of the reactor makes it possible to build a containment vessel. In this case it is possible to eliminate the danger of the reactor core drying out and thus cooling of the reactor in emergency situations can be simplified substantially. In an integrated layout, however, access is more difficult to the equipment inside the reactor, thus limiting or complicating maintenance work. The integrated layout, therefore, requires the use of highly reliable equipment built according to designs that have been proven in operation and have been passed representative service-life tests under laboratory conditions. The integrated layout considerably increases the mass and size characteristics of the reactor. New solutions thus are needed for the organization of work on reactor fabrication and assembly. In the case of the BN-600 and Superphenix reactors the welding of the reactor vessels and the assembly work were done on the building site

Energy Multiplier Module (EM{sup 2}) - advanced small modular reactor for electricity generation

Energy Technology Data Exchange (ETDEWEB)

Bertch, T.; Schleicher, R.; Choi, H.; Rawls, J., E-mail: timothy.bertch@ga.com [General Atomics, San Diego, California (United States)

2013-07-01

In order to provide cost effective nuclear energy in other than large reactor, large grid applications, fission technology needs to make further advances. 'Convert and burn' fast reactors offer long life cores, improved fuel utilization, reduced waste and other benefits while achieving cost effective energy production in a smaller reactor. General Atomics' Energy Multiplier Module (EM{sup 2}), a helium-cooled compact fast reactor that augments its fissile fuel load with either depleted uranium (DU) or used nuclear fuel (UNF). The convert and burn in-situ provides 250 MWe with a 30 year core life. High temperature provides a simple, high efficiency direct cycle gas turbine which along with modular construction, fewer systems, road shipment and minimum on site construction support cost effectiveness. Additional advantages in fuel cycle, non-proliferation and siting flexibility and its ability to meet all safety requirements make for an attractive power source, especially in remote and small grid regions. (author)

International Thermonuclear Experimental Reactor (ITER) plant layout and site services

International Nuclear Information System (INIS)

Chuyanov, V.

2001-01-01

The ITER site has not been determined at this time. Nevertheless, to develop a construction plan and a cost estimate, it is necessary to have a detailed layout of the buildings, structures, and outdoor equipment integrated with the balance of plant service systems prototypical of large fusion power plants. These services include electric power for magnet feeds and plasma heating systems, cryogenic and conventional cooling systems, compressed air, gas supplies, de-mineralized water, steam, and drainage. Nuclear grade facilities are provided to handle tritium fuel and activated waste, as well as to prevent radioactive exposure of either the workers or the public. To avoid interference between services of different types and for efficient arrangement of buildings, structures, and equipment within the site area, a plan was developed which segregated different classes of services to four quadrants surrounding the tokamak building, placed at the approximate geographic center of the site. Location of the twenty-seven buildings on the generic site was selected to meet all design requirements at minimum total project cost. A similar approach has been used to determine the location of services above, at, and below grade. The generic site plan can be adapted to the site selected for ITER without significant changes to the buildings or equipment. Some rearrangements may be required by site topography resulting primarily in changes to the length of services that link the buildings and equipment. (author)

International Thermonuclear Experimental Reactor (ITER) plant layout and site services

International Nuclear Information System (INIS)

Chuyanov, V.

1999-01-01

The ITER site has not been determined at this time. Nevertheless, to develop a construction plan and a cost estimate, it is necessary to have a detailed layout of the buildings, structures, and outdoor equipment integrated with the balance of plant service systems prototypical of large fusion power plants. These services include electric power for magnet feeds and plasma heating systems, cryogenic and conventional cooling systems, compressed air, gas supplies, de-mineralized water, steam, and drainage. Nuclear grade facilities are provided to handle tritium fuel and activated waste, as well as to prevent radioactive exposure of either the workers or the public. To avoid interference between services of different types and for efficient arrangement of buildings, structures, and equipment within the site area, a plan was developed which segregated different classes of services to four quadrants surrounding the tokamak building, placed at the approximate geographic center of the site. Location of the twenty-seven buildings on the generic site was selected to meet all design requirements at minimum total project cost. A similar approach has been used to determine the location of services above, at, and below grade. The generic site plan can be adapted to the site selected for ITER without significant changes to the buildings or equipment. Some rearrangements may be required by site topography resulting primarily in changes to the length of services that link the buildings and equipment. (author)

Nuclear Reactor RA Safety Report, Format and Contents

International Nuclear Information System (INIS)

1986-11-01

This is a new complete version of the safety report of nuclear reactor RA is made according to the recommendations of the IAEA. Report includes all the relevant data needed for evaluation of safe operation of this nuclear facility. Each of seven volumes of this report cover separate topics as follows: (1) introduction; (2) Site characteristics; (3) description of the reactor building and installations; (4) description of the reactor; (5) description of the coolant system; (6) description of the regulation and safety instrumentation; (7) description of the power supply system; (8) description of the auxiliary systems; (9) radiation protection issues; (10) radioactive waste management (11) reactor operation; (12) accident analysis during previous operation; (13) analysis of possible accident causes; (14) safety analysis and preventive actions: (15) analysis of significant accidents; (16) analysis of maximum possible accident; (17) environmental impact analysis in case of accident [sr

Transfer of Plutonium-Uranium Extraction Plant and N Reactor irradiated fuel for storage at the 105-KE and 105-KW fuel storage basins, Hanford Site, Richland Washington

International Nuclear Information System (INIS)

1995-07-01

The U.S. Department of Energy (DOE) needs to remove irradiated fuel from the Plutonium-Uranium Extraction (PUREX) Plant and N Reactor at the Hanford Site, Richland, Washington, to stabilize the facilities in preparation for decontamination and decommissioning (D ampersand D) and to reduce the cost of maintaining the facilities prior to D ampersand D. DOE is proposing to transfer approximately 3.9 metric tons (4.3 short tons) of unprocessed irradiated fuel, by rail, from the PUREX Plant in the 200 East Area and the 105 N Reactor (N Reactor) fuel storage basin in the 100 N Area, to the 105-KE and 105-KW fuel storage basins (K Basins) in the 100 K Area. The fuel would be placed in storage at the K Basins, along with fuel presently stored, and would be dispositioned in the same manner as the other existing irradiated fuel inventory stored in the K Basins. The fuel transfer to the K Basins would consolidate storage of fuels irradiated at N Reactor and the Single Pass Reactors. Approximately 2.9 metric tons (3.2 short tons) of single-pass production reactor, aluminum clad (AC) irradiated fuel in four fuel baskets have been placed into four overpack buckets and stored in the PUREX Plant canyon storage basin to await shipment. In addition, about 0.5 metric tons (0.6 short tons) of zircaloy clad (ZC) and a few AC irradiated fuel elements have been recovered from the PUREX dissolver cell floors, placed in wet fuel canisters, and stored on the canyon deck. A small quantity of ZC fuel, in the form of fuel fragments and chips, is suspected to be in the sludge at the bottom of N Reactor's fuel storage basin. As part of the required stabilization activities at N Reactor, this sludge would be removed from the basin and any identifiable pieces of fuel elements would be recovered, placed in open canisters, and stored in lead lined casks in the storage basin to await shipment. A maximum of 0.5 metric tons (0.6 short tons) of fuel pieces is expected to be recovered

Hydrogeological and Groundwater Flow Model for C, K, L, and P Reactor Areas, Savannah River Site, Aiken, South Carolina

Energy Technology Data Exchange (ETDEWEB)

Flach, G.P.

1999-02-24

A regional groundwater flow model encompassing approximately 100 mi{sup 2} surrounding the C, K. L. and P reactor areas has been developed. The Reactor flow model is designed to meet the planning objectives outlined in the General Groundwater Strategy for Reactor Area Projects by providing a common framework for analyzing groundwater flow, contaminant migration and remedial alternatives within the Reactor Projects team of the Environmental Restoration Department.

The Oak Ridge Research Reactor: safety analysis: Volume 2, supplement 2

International Nuclear Information System (INIS)

Hurt, S.S.

1986-11-01

The Oak Ridge Research Reactor Safety Analysis was last updated via ORNL-4169, Vol. 2, Supplement 1, in May of 1978. Since that date, several changes have been effected through the change-memo system described below. While these changes have involved the cooling system, the electrical system, and the reactor instrumentation and controls, they have not, for the most part, presented new or unreviewed safety questions. However, some of the changes have been based on questions or recommendations stemming from safety reviews or from reactor events at other sites. This paper discusses those changes which were judged to be safety related and which include revisions to the syphon-break system and changes related to seismic considerations which were very recently completed. The maximum hypothetical accident postulated in the original safety analysis requires dynamic containment and filtered flow for compliance with 10CFR100 limits at the site boundary

Special Purpose Nuclear Reactor (5 MW) for Reliable Power at Remote Sites Assessment Report

Energy Technology Data Exchange (ETDEWEB)

Sterbentz, James William [Idaho National Lab. (INL), Idaho Falls, ID (United States). Nuclear Science and Technology Division; Werner, James Elmer [Idaho National Lab. (INL), Idaho Falls, ID (United States). Nuclear Science and Technology Division; McKellar, Michael George [Idaho National Lab. (INL), Idaho Falls, ID (United States). Nuclear Science and Technology Division; Hummel, Andrew John [Idaho National Lab. (INL), Idaho Falls, ID (United States). Nuclear Science and Technology Division; Kennedy, John Charles [Idaho National Lab. (INL), Idaho Falls, ID (United States). Nuclear Science and Technology Division; Wright, Richard Neil [Idaho National Lab. (INL), Idaho Falls, ID (United States). Nuclear Science and Technology Division; Biersdorf, John Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States). Nuclear Science and Technology Division

2017-04-01

The Phenomena Identification and Ranking Table (PIRT) technique was conducted on the Special Purpose Reactor nuclear plant design. The PIRT is a structured process to identify safety-relevant/safety-significant phenomena and assess the importance and knowledge base by ranking the phenomena. The Special Purpose Reactor is currently in the conceptual design stage. The candidate reactor has a solid monolithic stainless steel core with an array of heat pipes and fuel pellets embedded in the monolith. The heat pipes are used to remove heat from the core using simple, reliable, and well-characterized physics (capillarity, boiling, and condensation). In the initial design, one heat exchanger is used for the working fluid that produces energy, and a second heat exchanger is used to remove decay heat in emergency or shutdown conditions. In addition, a power conversion cycle such as an open-air Brayton system is available as an option for power conversion and process heat. This report summarizes and documents the process and scope of the four PIRT reviews, noting the major activities and conclusions. The identified phenomena, analyses, rationales, and associated ratings are presented along with a summary of the findings from the four individual PIRTs, namely (1) Reactor Accident and Normal Operations, (2) Heat Pipes, (3) Materials, and (4) Power Conversion. The PIRT reports for these four major system areas evaluated are attached as appendixes to this report and provide considerably more detail about each assessment as well as a more complete listing of the phenomena that were evaluated.

Safety of Research Reactors. Specific Safety Requirements (French Edition)

International Nuclear Information System (INIS)

2017-01-01

This Safety Requirements publication establishes requirements for all main areas of safety for research reactors, with particular emphasis on requirements for design and operation. It explains the safety objectives and concepts that form the basis for safety and safety assessment for all stages in the lifetime of a research reactor. Technical and administrative requirements for the safety of new research reactors are established in accordance with these objectives and concepts, and they are to be applied to the extent practicable for existing research reactors. The safety requirements established in this publication for the management of safety and regulatory supervision apply to site evaluation, design, manufacturing, construction, commissioning, operation (including utilization and modification), and planning for decommissioning of research reactors (including critical assemblies and subcritical assemblies). The publication is intended for use by regulatory bodies and other organizations with responsibilities in these areas and in safety analysis, verification and review, and the provision of technical support.

Reactor core and initially loaded reactor core of nuclear reactor

International Nuclear Information System (INIS)

Koyama, Jun-ichi; Aoyama, Motoo.

1989-01-01

In BWR type reactors, improvement for the reactor shutdown margin is an important characteristic condition togehter with power distribution flattening . However, in the reactor core at high burnup degree, the reactor shutdown margin is different depending on the radial position of the reactor core. That is , the reactor shutdown margin is smaller in the outer peripheral region than in the central region of the reactor core. In view of the above, the reactor core is divided radially into a central region and as outer region. The amount of fissionable material of first fuel assemblies newly loaded in the outer region is made less than the amount of the fissionable material of second fuel assemblies newly loaded in the central region, to thereby improve the reactor shutdown margin in the outer region. Further, the ratio between the amount of the fissionable material in the upper region and that of the fissionable material in the lower portion of the first fuel assemblies is made smaller than the ratio between the amount of the fissionable material in the upper region and that of the fissionable material in the lower region of the second fuel assemblies, to thereby obtain a sufficient thermal margin in the central region. (K.M.)

Some technical solutions on organization and technology of reactor room component mounting

International Nuclear Information System (INIS)

Romanovskij, V.I.

1982-01-01

Design of the production equipment for mounting sites of heat facilities of the Zaporozhe NPP is considered. Plan of the production equipment for mounting sites of heat facilities and flowsheet of mounting of supporting truss of the reactor are presented

Mitigative techniques and analysis of generic site conditions for ground-water contamination associated with severe accidents

Energy Technology Data Exchange (ETDEWEB)

Shafer, J.M.; Oberlander, P.L.; Skaggs, R.L.

1984-04-01

The purpose of this study is to evaluate the feasibility of using ground-water contaminant mitigation techniques to control radionuclide migration following a severe commercial nuclear power reactor accident. The two types of severe commercial reactor accidents investigated are: (1) containment basemat penetration of core melt debris which slowly cools and leaches radionuclides to the subsurface environment, and (2) containment basemat penetration of sump water without full penetration of the core mass. Six generic hydrogeologic site classifications are developed from an evaluation of reported data pertaining to the hydrogeologic properties of all existing and proposed commercial reactor sites. One-dimensional radionuclide transport analyses are conducted on each of the individual reactor sites to determine the generic characteristics of a radionuclide discharge to an accessible environment. Ground-water contaminant mitigation techniques that may be suitable, depending on specific site and accident conditions, for severe power plant accidents are identified and evaluated. Feasible mitigative techniques and associated constraints on feasibility are determined for each of the six hydrogeologic site classifications. The first of three case studies is conducted on a site located on the Texas Gulf Coastal Plain. Mitigative strategies are evaluated for their impact on contaminant transport and results show that the techniques evaluated significantly increased ground-water travel times. 31 references, 118 figures, 62 tables.

Mitigative techniques and analysis of generic site conditions for ground-water contamination associated with severe accidents

International Nuclear Information System (INIS)

Shafer, J.M.; Oberlander, P.L.; Skaggs, R.L.

1984-04-01

The purpose of this study is to evaluate the feasibility of using ground-water contaminant mitigation techniques to control radionuclide migration following a severe commercial nuclear power reactor accident. The two types of severe commercial reactor accidents investigated are: (1) containment basemat penetration of core melt debris which slowly cools and leaches radionuclides to the subsurface environment, and (2) containment basemat penetration of sump water without full penetration of the core mass. Six generic hydrogeologic site classifications are developed from an evaluation of reported data pertaining to the hydrogeologic properties of all existing and proposed commercial reactor sites. One-dimensional radionuclide transport analyses are conducted on each of the individual reactor sites to determine the generic characteristics of a radionuclide discharge to an accessible environment. Ground-water contaminant mitigation techniques that may be suitable, depending on specific site and accident conditions, for severe power plant accidents are identified and evaluated. Feasible mitigative techniques and associated constraints on feasibility are determined for each of the six hydrogeologic site classifications. The first of three case studies is conducted on a site located on the Texas Gulf Coastal Plain. Mitigative strategies are evaluated for their impact on contaminant transport and results show that the techniques evaluated significantly increased ground-water travel times. 31 references, 118 figures, 62 tables

Concerning installation of reactor at Noto nuclear power plant of Hokuriku Electric Power Co., Inc. (reply to inquiry)

International Nuclear Information System (INIS)

1988-01-01

In response to an inquiry on the conformity of the title issue to the applicable law concerning nuclear material, nuclear fuel and nuclear reactor, the Nuclear Safety Commission ordered the Nuclear Reactor Safety Expert Group to make a study, made an examination after receiving a report from the Group, and submit the findings to the Minister of International Trade and Industry. The study on the site conditions covered the site location, geology, effects or earthquakes, meteorology, hydrology and social environment. The study on the safety design of the reactor covered the design of the facilities as a whole, anti-earthquake design, reactor, instrumentation, reactor shutdown system, reactivity control, protection, cooling system, reactor vessel, fuel handling, fuel storage, and radiation control. The study also included exposure evaluation, abnormal transient state analysis and accident analysis. It is concluded that the relevant company has a technical capability required for the installation and proper operation of the reactor in question, and that the reactor will have adequate safety with no possibility of causing a disaster. (Nogami, K.)

Seismic PSA method for multiple nuclear power plants in a site

Energy Technology Data Exchange (ETDEWEB)

Hakata, Tadakuni [Nuclear Safety Commission, Tokyo (Japan)

2007-07-15

The maximum number of nuclear power plants in a site is eight and about 50% of power plants are built in sites with three or more plants in the world. Such nuclear sites have potential risks of simultaneous multiple plant damages especially at external events. Seismic probabilistic safety assessment method (Level-1 PSA) for multi-unit sites with up to 9 units has been developed. The models include Fault-tree linked Monte Carlo computation, taking into consideration multivariate correlations of components and systems from partial to complete, inside and across units. The models were programmed as a computer program CORAL reef. Sample analysis and sensitivity studies were performed to verify the models and algorithms and to understand some of risk insights and risk metrics, such as site core damage frequency (CDF per site-year) for multiple reactor plants. This study will contribute to realistic state of art seismic PSA, taking consideration of multiple reactor power plants, and to enhancement of seismic safety. (author)

The brief introduction to decommissioning of nuclear reactor projects

International Nuclear Information System (INIS)

Zhao Shixin

1991-01-01

The basic concept and procedure of the decommissioning of nuclear reactor project and the three stages of decommissioning defined by IAEA are introduced. The main work of decommissioning of nuclear reactor are as following: (1) the documentary and technological preparation; (2) the site preparation of decommissioning project; (3) the dismantling of equipment piping system and components; (4) the decontamination of the piping system before and after decomminssioning; (5) the storage and disposal of the operational and decommissioning waste

The brief introduction to decommissioning of nuclear reactor projects

Energy Technology Data Exchange (ETDEWEB)

Shixin, Zhao [Beijing Inst. of Nuclear Engineering (China)

1991-08-01

The basic concept and procedure of the decommissioning of nuclear reactor project and the three stages of decommissioning defined by IAEA are introduced. The main work of decommissioning of nuclear reactor are as following: (1) the documentary and technological preparation; (2) the site preparation of decommissioning project; (3) the dismantling of equipment piping system and components; (4) the decontamination of the piping system before and after decomminssioning; (5) the storage and disposal of the operational and decommissioning waste.

An expert system for pressurized water reactor load maneuvers

International Nuclear Information System (INIS)

Chaung Lin; Jungping Chen; Yihjiunn Lin; Lianshin Lin

1993-01-01

Restartup after reactor shutdown and load-follow operations are the important tasks in operating pressurized water reactors. Generally, the most efficient method is to apply constant axial offset control (CAOC) strategy during load maneuvers. An expert system using CAOC strategy, fuzzy reasoning, a two-node core model, and operational constraints has been developed. The computation time is so short that this system, which leads to an approximate closed-loop control, could be useful for on-site calculation

Rocketdyne Propulsion and Power DOE Operations annual site environmental report 1997

International Nuclear Information System (INIS)

Robinson, K.S.

1998-01-01

This annual report discusses environmental monitoring at two manufacturing and test sites operated in the Los Angeles area by Rocketdyne Propulsion and Power of Boeing North American, Inc. These are identified as Area 4 of the SSFL and the De Soto site. These sites have been used for research and development (R and D), engineering, and testing in a broad range of technical fields primarily in energy research and nuclear reactor technology. The De Soto site had research and development laboratories involved with nuclear research. This work was terminated in 1995 and only D and D activities will have potential for impact on the environment. Since 1956, Area 4 has been used for work with nuclear materials, including fabricating nuclear reactor fuels, testing nuclear reactors, and dissembling used fuel elements. This work ended in 1988 and subsequent efforts have been directed toward decommissioning and decontamination of the former nuclear facilities. The primary purpose of this report is to present information on environmental and effluent monitoring of DOE-sponsored activities to the regulatory agencies responsible for oversight. Information presented here concentrates on Area 4 at SSFL, which is the only area at SSFL where DOE operations were performed

The siting of nuclear power stations in Britain

International Nuclear Information System (INIS)

Wright, H.A.

1975-01-01

It is a fundamental precept that all prudent precautions should be taken. The secondary contribution to public safety derived by a proper choice of site must therefore be utilised. A siting policy should limit the choice of site but give the Utility sufficient freedom of choice to enable the more remote sites to be available for the adoption of new reactor types. For a significant release few people should be affected sufficiently to require evacuation, and account must also be taken of population centres possibly up to 20 miles from the site. (orig.) [de

The Hanford Site: An anthology of early histories

Energy Technology Data Exchange (ETDEWEB)

Gerber, M.S.

1993-10-01

This report discusses the following topics: Memories of War: Pearl Harbor and the Genesis of the Hanford Site; safety has always been promoted at the Hanford Site; women have an important place in Hanford Site history; the boom and bust cycle: A 50-year historical overview of the economic impacts of Hanford Site Operations on the Tri-Cities, Washington; Hanford`s early reactors were crucial to the sites`s history; T-Plant made chemical engineering history; the UO{sub 3} plant has a long history of service. PUREX Plant: the Hanford Site`s Historic Workhorse. PUREX Plant Waste Management was a complex challenge; and early Hanford Site codes and jargon.

Action for declaration of annulment of reactor construction permit dismissed

International Nuclear Information System (INIS)

Anon.

1982-01-01

The Higher Administrative Court of Rheinland Pfalz has confirmed two decisions by the Koblenz Administrative Court dismissing an actions to declare the annulment of the partial construction permit issued for the Muelheim-Kaerlich reactor. Appeal was not admitted. The plaintiffs, who are under age and were represented by their father, are permanently resident in Schleswig-Holstein, at about 470 km from the site and have a further residence in Mainz, about 60 km away from the site. They plead to have a legitimate interest in the declaration of nullity on the grounds of the uncertainty created in legal matters by the delivery of the permit and its being unconstitutional as well as for ideological and religious reasons. The ruling deals also with the importance of the distance from the site of a nuclear reactor, which is considered to be such as to exclude the 'necessary spatial relation'. (orig./HP) [de

Machinery Vibration Monitoring Program at the Savannah River Site

International Nuclear Information System (INIS)

Potvin, M.M.

1990-01-01

The Reactor Maintenance's Machinery Vibration Monitoring Program (MVMP) plays an essential role in ensuring the safe operation of the three Production Reactors at the Westinghouse Savannah River Company (WRSC) Savannah River Site (SRS). This program has increased machinery availability and reduced maintenance cost by the early detection and determination of machinery problems. This paper presents the Reactor Maintenance's Machinery Vibration Monitoring Program, which has been documented based on Electric Power Research Institute's (EPRI) NP-5311, Utility Machinery Monitoring Guide, and some examples of the successes that it has enjoyed

Distributional effects of the fiscal impact of power plant siting

International Nuclear Information System (INIS)

Vogt, D.P.; Bjornstad, D.J.

1976-01-01

Classical economic base analysis is grounded in the concept that export activity drives the local economy and that economic impacts due to development can be traced to changes in the export base. Local government activities are frequently treated as a consequence of economic change, but no significant economic impact has been associated with imported tax dollars. In this paper the siting of a power reactor is examined, and it is concluded that the major economic impact related to the siting may result from increases in the tax base, which permit either increased public expenditure or increased disposable income through tax rate decreases. It is argued that as the fraction of the tax base that is owned nonlocally increases, the community perceives a price change, since smaller amounts of local income must be foregone to purchase a constant level of public services. This relationship is estimated using a sample of rural counties drawn from the State of Tennessee. The empirical results generally support the importance of the price variable in determining discretionary expenditures out of local disposable incomes. This finding conforms to other results obtained through an examination of actual reactor sitings, and points to the importance of understanding community responses to increased tax base for understanding local economic impacts from reactor siting

Oklo reactors: natural analogs to nuclear waste repositories

International Nuclear Information System (INIS)

Curtis, D.B.; Benjamin, T.M.; Gancarz, A.J.

1981-01-01

The 2-billion-year-old fossil reactors at Oklo are ancient natural nuclear waste sites. Isotope dilution mass spectrometric analyses of the fission products in the reactor core uraninite and the peripheral pelitic sandstone provide data for calculating the reactor operating parameters, the quantities of fissiogenic isotopes produced, the fraction of these isotopes retained in the cores, and the location in the peripheral rocks of the fissiogenic fraction lost from the cores. For a duration of criticality of 3 x 10 5 yrs, the thermal plus resonance neutron fluence ranged between 10 20 and 10 21 neutrons/cm 2 . The fraction of technetium (60 to 85%), ruthenium (75 to 90%), and neodymium (85 to 100%) retained is negatively correlated with fluence. The lost fission products are contained within a few tens of meters of their source, the reactor cores. The systematics of the decay of 99 Tc (t/sub 1/2/ = 2.13 x 10 5 yr) to 99 Ru limits the period of fissiogenic element migration to approximately 1 million yr at a time 2 billion yr ago. Thermodynamic calculations of the temperature-dependent solubilities indicate that the loss of fissiogenic elements is diffusion controlled, whereas retention in the surrounding rocks is a result of temperature-dependent deposition from an aqueous solution. These results concerning the geochemistry of technetium, ruthenium, and neodymium at a natural waste site support the concept of geologic burial of man-made radioactive wastes

Department of Energy's Advanced Test Reactor (ATR), July 14--18, 1980: An independent on-site safety review

International Nuclear Information System (INIS)

1981-02-01

The intent of this review was not to conduct a detailed in-depth audit, but rather to make a broad management assessment of ATR operations. The results of the review should only be considered as having identified trends or indications. The Team's observations and recommendations for the most part are based upon standards used for licensed reactor facility practices. These standards form the basis for many of the comments in this report. The Team believes that a uniform minimum standard of performance should be achieved in the operation of DOE reactors. In order to assure that this is accomplished, clear standards are necessary. Consistent with the past AEC and ERDA policy, the Team has used the standards of the commercial nuclear power industry. It is recognized that this approach is conservative, in that the ATR reactor has a significantly greater degree of inherent safety (lower pressure, temperature, power, etc.) than a licensed reactor. Although the Review Team found no indications or evidence that the plant is being operated in an unsafe manner, various areas were identified where improvements are either needed or should be considered to increase the safety of reactor operations

On-site and off-site emergency planning at Cekmece Nuclear Research and Training Centre

International Nuclear Information System (INIS)

Soyberk, O.A.

1986-01-01

An emergency plan was prepared for minimizing the consequences of any unforeseen radiation accident in Cekmece Nuclear Research and Training Centre (CNAEM) in Istanbul, Turkey. CNAEM is situated near Kucukcekmece Lake, which is about 30 km to the west of Istanbul. It includes two pool-type research reactors of 1 MW(th) and 5 MW(th). The population in the nearest inhabited areas varies from 1000 to 50,000. Accidents are classified, according to their severity, into three categories at CNAEM: (a) local emergency, (b) on-site emergency, (c) off-site emergency. During local emergency situations evacuation is not necessary. An on-site emergency situation requires the evacuation of personnel from the plant. Personnel hearing the emergency alarm should move directly to the preselected place as soon as possible. An off-site emergency is any accident that leads to widespread contamination outside the boundary. In this situation the Turkish Atomic Energy Authority and governmental authorities are notified immediately. The emergency organization group consists of: (a) Plant Superintendent, (b) Emergency Director, (c) Reactor Supervisor, (d) Senior Health Physicist, (e) Reactor Shift Operator, (f) Health Physicists. The administration building will be used as the Emergency Control Centre. The emergency teams working under the direction of the Emergency Director consist of: (a) Health Physics, (b) Fire and Rescue, (c) First Aid and Decontamination, (d) Transportation, (e) Security and Patrol. The emergency situation is evaluated in three phases at CNAEM. The first phase is the first few hours after the beginning of the accident. The second phase is between 8-10 hours or more following the first phase. The third phase is the recovery phase. The integrated doses over periods of two hours and two days are calculated according to the situation of the core, i.e. total or partial melting, and weather conditions. The results of the calculated parameters can be adapted to possible

National Report of Bulgaria [National practice at WWER sites

International Nuclear Information System (INIS)

2017-01-01

Kozloduy NPP Plc. is located in north-western Bulgaria at about 3 km from the Danube River, which serves as a source of cooling water and a receiver of liquid released from the plant (Fig. I.3). Six nuclear units were constructed on Kozloduy NPP site. Units 1 to 4 are WWER-440/230 reactors and Units 5 and 6 are WWER-1000/320 reactors. Units 1 to 4 were commissioned from 1974 to 1982. Units 5 and 6 were commissioned in 1987 and 1991, respectively. On December 31, 2002 Units 1 and 2 were shut down and on December 31, 2006 Units 3 and 4 were shut down as well. Spent Nuclear Fuel was removed from the pre-reactor pools and the reactors have been prepared for decommissioning. Units 1 and 2 (in 2008) and Units 3 and 4 (in 2012) were declared as Decommissioning Facilities by Ministerial Decree and outsourced from the plant. A separate complex consisting of facilities for treatment and conditioning of wet and dry solid radioactive waste (RAW) and a facility for storage of conditioned RAW was commissioned in 2001 on site. The complex is situated next to the Auxiliary Building of Units 5 and 6. In 2005 this complex was outsourced as a separate enterprise called the Specialized Enterprise for Radioactive Waste (SE RAW). There are two Spent Fuel Storage Facilities (SFSF) for wet and dry storage located on the plant site as well.

Radiological characterization and challenges at decommissioning sites

International Nuclear Information System (INIS)

Moore, Scott

2002-01-01

Scott Moore described the dose-based radiological characterisation process used in the USA, and four current characterisation issues faced there. His paper emphasized the importance of characterisation to control decommissioning hazards and costs: The License Termination Rule (LTR), Subpart E to 10 CFR Part 20, provides the dose-based criteria that the U.S. Nuclear Regulatory Commission (NRC) uses as the basis for regulating cleanup at material and reactor sites. The LTR permits the release of sites for unrestricted use, if the radioactivity that is distinguishable from background results in a total effective dose equivalent to an average member of a critical group that does not exceed 0.25 milli-Sievert per year (mSv/yr) (25 milli-rem/year) and the residual radioactivity has been reduced to levels that are as low as reasonably achievable. Additionally, the LTR establishes criteria for license termination with restrictions on future land use, which allow for a dose to the critical group of 0.25 mSv/yr (25 milli-rem/year) with restrictions in place, and 1 mSv/yr (100 milli-rem/year) if the restrictions fail. In certain circumstances as outlined in Subpart E, a dose as high as 5 mSv/yr (500 milli-rem/year) is permitted if restrictions fail. Following issuance of the dose-based LTR in 1997, NRC staff developed the Standard Review Plan for Decommissioning Plans (NUREG-1727). NUREG-1727 is a guidance document that describes the methods that NRC has determined are acceptable for implementing the LTR and other decommissioning regulations. While NUREG-1727 is focused on the review of decommissioning plans for nuclear material sites, it provides general guidance that in many cases is applicable to reactor sites (e.g., review criteria for dose-modeling and radiological surveys). In addition to NUREG-1727, staff developed the Standard Review Plan for Evaluating Nuclear Power Reactor License Termination Plans (NUREG-1700) as specific guidance for reactor decommissioning. NUREG

Nuclear reactor physics course for reactor operators

International Nuclear Information System (INIS)

Baeten, P.

2006-01-01

The education and training of nuclear reactor operators is important to guarantee the safe operation of present and future nuclear reactors. Therefore, a course on basic 'Nuclear reactor physics' in the initial and continuous training of reactor operators has proven to be indispensable. In most countries, such training also results from the direct request from the safety authorities to assure the high level of competence of the staff in nuclear reactors. The aim of the basic course on 'Nuclear Reactor Physics for reactor operators' is to provide the reactor operators with a basic understanding of the main concepts relevant to nuclear reactors. Seen the education level of the participants, mathematical derivations are simplified and reduced to a minimum, but not completely eliminated