Contaminant fluxes through site containment barriers: Performance assessment and illustrative results

International Nuclear Information System (INIS)

Vita, C.L.

1994-01-01

Contaminant mass flux by advective and diffusive transport is predicted for five containment barriers that use one or more clay liners, flexible membrane liners (FMLs), or liquid collection and removal systems (LCRS)s. Barriers are engineered systems intended to contain and isolate site contaminants from the environment. Barriers include liners, caps, and cutoff walls. Barriers may be used in contaminated-site cleanups (including CERCLA and RCRA), RCRA landfills, or other RCRA TSDFs. Concepts are provided for barrier performance assessment, including analysis and optimization, for meeting performance requirements and controlling risk at minimum cost. Concepts and results can help in planning, designing, or evaluating and communicating, the use or effectiveness of proposed or existing barriers for site cleanups or waste containment. 15 refs., 6 figs., 5 tabs

US DOE-EM On-Site Disposal Cell Working Group - Fostering Communication On Performance Assessment Challenges

Energy Technology Data Exchange (ETDEWEB)

Seitz, Roger R. [Savannah River Site (SRS), Aiken, SC (United States); Suttora, Linda C. [U.S. Department of Energy, Office of Site Restoration, Germantown, MD (United States); Phifer, Mark [Savannah River Site (SRS), Aiken, SC (United States)

2014-03-01

On-site disposal cells are in use and being considered at several U.S. Department of Energy (USDOE) sites as the final disposition for large amounts of waste associated with cleanup of contaminated areas and facilities. These facilities are typically developed with regulatory oversight from States and/or the US Environmental Protection Agency (USEPA) in addition to USDOE. The facilities are developed to meet design standards for disposal of hazardous waste as well as the USDOE performance based standards for disposal of radioactive waste. The involvement of multiple and different regulators for facilities across separate sites has resulted in some differences in expectations for performance assessments and risk assessments (PA/RA) that are developed for the disposal facilities. The USDOE-EM Office of Site Restoration formed a working group to foster improved communication and sharing of information for personnel associated with these Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) disposal cells and work towards more consistent assumptions, as appropriate, for technical and policy considerations related to performance and risk assessments in support of a Record of Decision and Disposal Authorization Statement. The working group holds teleconferences, as needed, focusing on specific topics of interest. The topics addressed to date include an assessment of the assumptions used for performance assessments and risk assessments (PA/RAs) for on-site disposal cells, requirements and assumptions related to assessment of inadvertent intrusion, DOE Manual 435.1-1 requirements, and approaches for consideration of the long-term performance of liners and covers in the context of PAs. The working group has improved communication among the staff and oversight personnel responsible for onsite disposal cells and has provided a forum to identify and resolve common concerns.

COMPLETION OF THE TRANSURANIC GREATER CONFINEMENT DISPOSAL BOREHOLE PERFORMANCE ASSESSMENT FOR THE NEVADA TEST SITE

International Nuclear Information System (INIS)

Colarusso, Angela; Crowe, Bruce; Cochran, John R.

2003-01-01

Classified transuranic material that cannot be shipped to the Waste Isolation Pilot Plant in New Mexico is stored in Greater Confinement Disposal boreholes in the Area 5 Radioactive Waste Management Site on the Nevada Test Site. A performance assessment was completed for the transuranic inventory in the boreholes and submitted to the Transuranic Waste Disposal Federal Review Group. The performance assessment was prepared by Sandia National Laboratories on behalf of the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office using an iterative methodology that assessed radiological releases from the intermediate depth disposal configuration against the regulatory requirements of the 1985 version of 40 CFR 191 of the U.S. Environmental Protection Agency. The transuranic materials are stored at 21 to 37 m depth (70 to 120 ft) in large diameter boreholes constructed in the unsaturated alluvial deposits of Frenchman Flat. Hydrologic processes that affect long- term isolation of the radionuclides are dominated by extremely slow upward rates of liquid/vapor advection and diffusion; there is no downward pathway under current climatic conditions and there is no recharge to groundwater under future ''glacial'' climatic conditions. A Federal Review Team appointed by the Transuranic Waste Disposal Federal Review Group reviewed the Greater Confinement Disposal performance assessment and found that the site met the majority of the regulatory criteria of the 1985 and portions of the 1993 versions of 40 CFR 191. A number of technical and procedural issues required development of supplemental information that was incorporated into a final revision of the performance assessment. These issues include inclusion of radiological releases into the complementary cumulative distribution function for the containment requirements associated with drill cuttings from inadvertent human intrusion, verification of mathematical models used in the performance

Guidelines for radiological performance assessment of DOE low-level radioactive waste disposal sites

International Nuclear Information System (INIS)

Case, M.J.; Otis, M.D.

1988-07-01

This document provides guidance for conducting radiological performance assessments of Department of Energy (DOE) low-level radioactive waste (LLW) disposal facilities. The guidance is specifically intended to provide the fundamental approach necessary to meet the performance assessment requirements. The document is written for LLW facility operators or other personnel who will manage the performance assessment task. The document is meant to provide guidance for conducting performance assessments in a generally consistent manner at all DOE LLW disposal facilities. The guidance includes a summary of performance objectives to be met by LLW disposal facilities (these objectives are derived from current DOE and other applicable federal regulatory guidelines); specific criteria for an adequate performance assessment and from which a minimum set of required calculations may be determined; recommendations of methods for screening critical components of the analysis system so that these components can be addressed in detail; recommendations for the selection of existing models and the development of site-specific models; recommendations of techniques for comparison of assessment results with performance objectives; and a summary of reporting requirements

Geochemical Data Package for Performance Assessment Calculations Related to the Savannah River Site

Energy Technology Data Exchange (ETDEWEB)

Kaplan, Daniel I. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2010-03-15

The Savannah River Site disposes of low-activity radioactive waste within subsurface-engineered facilities. One of the tools used to establish the capacity of a given site to safely store radioactive waste (i.e., that a site does not exceed its Waste Acceptance Criteria) is the Performance Assessment (PA). The objective of this document is to provide the geochemical values for the PA calculations. This work is being conducted as part of the on-going maintenance program that permits the PA to periodically update existing calculations when new data become available.

Proceedings of the tenth annual DOE low-level waste management conference: Session 2: Site performance assessment

International Nuclear Information System (INIS)

1988-12-01

This document contains twelve papers on various aspects of low-level radioactive waste management. Topics of this volume include: performance assessment methodology; remedial action alternatives; site selection and site characterization procedures; intruder scenarios; sensitivity analysis procedures; mathematical models for mixed waste environmental transport; and risk assessment methodology. Individual papers were processed separately for the database

Proceedings of the tenth annual DOE low-level waste management conference: Session 2: Site performance assessment

Energy Technology Data Exchange (ETDEWEB)

1988-12-01

This document contains twelve papers on various aspects of low-level radioactive waste management. Topics of this volume include: performance assessment methodology; remedial action alternatives; site selection and site characterization procedures; intruder scenarios; sensitivity analysis procedures; mathematical models for mixed waste environmental transport; and risk assessment methodology. Individual papers were processed separately for the database. (TEM)

A Probabilistic Performance Assessment Study of Potential Low-Level Radioactive Waste Disposal Sites in Taiwan

Science.gov (United States)

Knowlton, R. G.; Arnold, B. W.; Mattie, P. D.; Kuo, M.; Tien, N.

2006-12-01

For several years now, Taiwan has been engaged in a process to select a low-level radioactive waste (LLW) disposal site. Taiwan is generating LLW from operational and decommissioning wastes associated with nuclear power reactors, as well as research, industrial, and medical radioactive wastes. The preliminary selection process has narrowed the search to four potential candidate sites. These sites are to be evaluated in a performance assessment analysis to determine the likelihood of meeting the regulatory criteria for disposal. Sandia National Laboratories and Taiwan's Institute of Nuclear Energy Research have been working together to develop the necessary performance assessment methodology and associated computer models to perform these analyses. The methodology utilizes both deterministic (e.g., single run) and probabilistic (e.g., multiple statistical realizations) analyses to achieve the goals. The probabilistic approach provides a means of quantitatively evaluating uncertainty in the model predictions and a more robust basis for performing sensitivity analyses to better understand what is driving the dose predictions from the models. Two types of disposal configurations are under consideration: a shallow land burial concept and a cavern disposal concept. The shallow land burial option includes a protective cover to limit infiltration potential to the waste. Both conceptual designs call for the disposal of 55 gallon waste drums within concrete lined trenches or tunnels, and backfilled with grout. Waste emplaced in the drums may be solidified. Both types of sites are underlain or placed within saturated fractured bedrock material. These factors have influenced the conceptual model development of each site, as well as the selection of the models to employ for the performance assessment analyses. Several existing codes were integrated in order to facilitate a comprehensive performance assessment methodology to evaluate the potential disposal sites. First, a need

Texas' performance assessment work

International Nuclear Information System (INIS)

Charbeneau, R.J.; Hertel, N.E.; Pollard, C.G.

1990-01-01

The Texas Low-Level Radioactive Waste Disposal Authority is completing two years of detailed on-site suitability studies of a potential low-level radioactive waste disposal site in Hudspeth County, Texas. The data from these studies have been used to estimate site specific parameters needed to do a performance assessment of the site. The radiological impacts of the site have been analyzed as required for a license application. The approach adopted for the performance assessment was to use simplified and yet conservative assumptions with regard to releases, radionuclide transport, and dose calculations. The methodologies employed in the performance assessment are reviewed in the paper. Rather than rely on a single computer code, a modular approach to the performance assessment was selected. The HELP code was used to calculate the infiltration rate through the trench covers and the amount of leachate released from this arid site. Individual pathway analyses used spreadsheet calculations. These calculations were compared with those from other computer models including CRRIS, INGDOS, PATHRAE, and MICROSHIELD copyright, and found to yield conservative estimates of the effective whole body dose. The greatest difficulty in performing the radiological assessment of the site was the selection of reasonable source terms for release into the environment. A surface water pathway is unreasonable for the site. Though also unlikely, the groundwater pathway with exposure through a site boundary well was found to yield the largest calculated dose. The more likely pathway including transport of leachate from the facility through the unsaturated zone and returning to the ground surface yields small doses. All calculated doses associated with normal releases of radioactivity are below the regulatory limits

Process of performance assessment

International Nuclear Information System (INIS)

King, C.M.; Halford, D.K.

1987-01-01

Performance assessment is the process used to evaluate the environmental consequences of disposal of radioactive waste in the biosphere. An introductory review of the subject is presented. Emphasis is placed on the process of performance assessment from the standpoint of defining the process. Performance assessment, from evolving experience at DOE sites, has short-term and long-term subprograms, the components of which are discussed. The role of mathematical modeling in performance assessment is addressed including the pros and cons of current approaches. Finally, the system/site/technology issues as the focal point of this symposium are reviewed

Performance Assessment Monitoring Plan for the Hanford Site Low-Level Waste Burial Grounds

International Nuclear Information System (INIS)

SONNICHSEN, J.C.

2000-01-01

As directed by the U.S. Department of Energy (DOE), Richland Operations Office (DOE-RL), Fluor Hanford, Inc. will implement the requirements of DOE Order 435.1, Radioactive Waste Management, as the requirements relate to the continued operation of the low-level waste disposal facilities on the Hanford Site. DOE Order 435.1 requires a disposal authorization statement authorizing operation (or continued operation) of a low-level waste disposal facility. The objective of this Order is to ensure that all DOE radioactive waste is managed in a manner that protects the environment and personnel and public health and safety. The manual (DOE Order 435.1 Manual) implementing the Order states that a disposal authorization statement shall be issued based on a review of the facility's performance assessment and composite analysis or appropriate Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) of 1980 documentation. The disposal authorization shall specify the limits and conditions on construction, design, operations, and closure of the low-level waste facility. Failure to obtain a disposal authorization statement shall result in shutdown of an operational disposal facility. In fulfillment of the requirements of DOE Order 435.1, a disposal authorization statement was issued on October 25, 1999, authorizing the Hanford Site to transfer, receive, possess, and dispose of low-level radioactive waste at the 200 East Area and the 200 West Area Low-Level Burial Grounds. The disposal authorization statement constitutes approval of the performance assessment and composite analysis, authorizes operation of the facility, and includes conditions that the disposal facility must meet. One of the conditions is that monitoring plans for the 200 East Area and 200 West Area Low-Level Burial Grounds be written and approved by the DOE-RL. The monitoring plan is to be updated and implemented within 1 year following issuance of the disposal authorization statement to

Management of the Area 5 Radioactive Waste Management Site using Decision-based, Probabilistic Performance Assessment Modeling

International Nuclear Information System (INIS)

Carilli, J.; Crowe, B.; Black, P.; Tauxe, J.; Stockton, T.; Catlett, K.; Yucel, V.

2003-01-01

Low-level radioactive waste from cleanup activities at the Nevada Test Site and from multiple sites across the U.S. Department of Energy (DOE) complex is disposed at two active Radioactive Waste Management Sites (RWMS) on the Nevada Test Site. These facilities, which are managed by the DOE National Nuclear Security Administration Nevada Site Office, were recently designated as one of two regional disposal centers and yearly volumes of disposed waste now exceed 50,000 m3 (> 2 million ft3). To safely and cost-effectively manage the disposal facilities, the Waste Management Division of Environmental Management has implemented decision-based management practices using flexible and problem-oriented probabilistic performance assessment modeling. Deterministic performance assessments and composite analyses were completed originally for the Area 5 and Area 3 RWMSs located in, respectively, Frenchman Flat and Yucca Flat on the Nevada Test Site. These documents provide the technical bases for issuance of disposal authorization statements for continuing operation of the disposal facilities. Both facilities are now in a maintenance phase that requires testing of conceptual models, reduction of uncertainty, and site monitoring all leading to eventual closure of the facilities and transition to long-term stewardship

The performance assessment impacts of disposal of high-moisture, low-level radioactive waste at the Nevada Test Site

International Nuclear Information System (INIS)

Crowe, B.M.; Hansen, W.; Hechnova, A.; Voss, C.; Waters, R.; Sully, M.; Levitt, D.

1999-01-01

A panel of independent scientists was convened by the Department of Energy to assess the performance impacts of disposal of low-level radioactive waste from the Fernald Environmental Management Project. This waste stream was involved in a transportation incident in December 1997. A resulting outgrowth of investigations of the transportation incident was the recognition that the waste was transported and disposed in stress-fractured metal boxes and some of the waste contained excess moisture (high volumetric water contents). The panel was charged with determining whether disposal of this waste in the Area 5 radioactive waste management site on the Nevada Test Site has impacted the conclusions of the completed performance assessment. Three questions were developed by the panel to assess performance impacts: (1) the performance impacts of reduced container integrity, (2) the impact of reduced container integrity on subsidence of waste in the disposal pits and (3) the performance impacts of excess moisture. No performance or subsidence impacts were noted from disposal of the Fernald waste. The impacts of excess moisture were assessed through simulation modeling of the movement of moisture in the vadose zone assuming high water contents (wet waste) for different percentages of the waste inventory. No performance impacts were noted for either the base-case scenario (ambient conditions) or a scenario involving subsidence and flooding of the waste cells. The absence of performance impacts results form the extreme conservatism used in the Area 5-performance assessment and the robust nature of the disposal site

The process of performance assessment

International Nuclear Information System (INIS)

King, C.M.; Halford, D.K.

1986-01-01

An introductory review of the subject of ''Performance Assessment'' will be presented. Emphasis will be placed on the process of performance assessment from the standpoint of defining the process. Performance assessment, from evolving experience at DOE sites, has short-term and long-term subprograms, the components of which will be discussed. The role of mathematical modeling in performance assessment will be addressed including the pros and cons of current approaches. Finally, the ''system/site/technology'' issues as the focal point of this symposium will be reviewed

Performance assessment strategy for low-level waste disposal sites

International Nuclear Information System (INIS)

Starmer, R.J.; Deering, L.G.; Weber, M.F.

1988-01-01

This paper describes US Nuclear Regulatory Commission (NRC) staff views on predicting the performance of low-level radioactive waste disposal facilities. Under the Atomic Energy Act, as amended, and the Low Level Radioactive Waste Policy Act, as amended, the NRC and Agreement States license land disposal of low-level radioactive waste (LLW) using the requirements in 10 CFR Part 61 or comparable state requirements. The purpose of this paper is to briefly describe regulatory requirements for performance assessment in low-level waste licensing, a strategy for performance assessments to support license applications, and NRC staff licensing evaluation of performance assessments. NRC's current activities in developing a performance assessment methodology will provide an overall systems modeling approach for assessing the performance of LLW disposal facilities. NRC staff will use the methodology to evaluate performance assessments conducted by applicants for LLW disposal facilities. The methodology will be made available to states and other interested parties

Hanford Site baseline risk assessment methodology

International Nuclear Information System (INIS)

1993-03-01

This methodology has been developed to prepare human health and environmental evaluations of risk as part of the Comprehensive Environmental Response, Compensation, and Liability Act remedial investigations (RIs) and the Resource Conservation and Recovery Act facility investigations (FIs) performed at the Hanford Site pursuant to the Hanford Federal Facility Agreement and Consent Order referred to as the Tri-Party Agreement. Development of the methodology has been undertaken so that Hanford Site risk assessments are consistent with current regulations and guidance, while providing direction on flexible, ambiguous, or undefined aspects of the guidance. The methodology identifies Site-specific risk assessment considerations and integrates them with approaches for evaluating human and environmental risk that can be factored into the risk assessment program supporting the Hanford Site cleanup mission. Consequently, the methodology will enhance the preparation and review of individual risk assessments at the Hanford Site

Performance assessment of the Greater Confinement Disposal facility on the Nevada Test Site: Comparing the performance of two conceptual site models

International Nuclear Information System (INIS)

Baer, T.A.; Price, L.L.; Gallegos, D.P.

1993-01-01

A small amount of transuranic (TRU) waste has been disposed of at the Greater Confinement Disposal (GCD) site located on the Nevada Test Site's (NTS) Radioactive Waste Management Site (RWMS). The waste has been buried in several deep (37 m) boreholes dug into the floor of an alluvial basin. For the waste to remain in its current configuration, the DOE must demonstrate compliance of the site with the TRU disposal requirements, 40 CFR 191. Sandia's approach to process modelling in performance assessment is to use demonstrably conservative models of the site. Choosing the most conservative model, however, can be uncertain. As an example, diffusion of contaminants upward from the buried waste in the vadose zone water is the primary mechanism of release. This process can be modelled as straight upward planar diffusion or as spherical diffusion in all directions. The former has high fluxes but low release areas, the latter has lower fluxes but is spread over a greater area. We have developed analytic solutions to a simple test problem for both models and compared the total integrated discharges. The spherical diffusion conceptual model results in at least five times greater release to the accessible environment than the planar model at all diffusivities. Modifying the planar model to allow for a larger release, however, compensated for the smaller original planar discharge and resulted in a new planar model that was more conservative that the spherical model except at low diffusivities

Performance Assessment of a Low-Level Radioactive Waste Disposal Site using GoldSim Integrated Systems Model

Science.gov (United States)

Merrell, G.; Singh, A.; Tauxe, J.; Perona, R.; Dornsife, W.; grisak, G. E.; Holt, R. M.

2011-12-01

Texas Commission on Environmental Quality has approved licenses for four landfills at the Waste Control Specialists (WCS) site located in Andrews County, West Texas. The site includes a hazardous waste landfill and three landfills for radioactive waste. An updated performance assessment is necessary prior to acceptance of waste at the landfills. The updated performance assessment a) provides for more realistic and flexible dose modeling capabilities, b) addresses all plausible release and accident scenarios as they relate to the performance objectives, c) includes impact of climate and hydrologic scenarios that may impact long-term performance of the landfill, d) addresses impact of cover naturalization and degradation on the landfill, and e) incorporates uncertainty and sensitivity analysis for critical parameters. For the updated performance assessment, WCS has developed an integrated systems level performance assessment model using the GoldSim platform. GoldSim serves as a model for integrating all of the major components of a performance assessment, which include the radionuclide source term, facility design, environmental transport pathways, exposure scenarios, and radiological doses. Unlike many computer models that are based on first principles, GoldSim is a systems level model that can be used to integrate and abstract more complex sub-models into one system. This can then be used to assess the results into a unified model of the disposal system and environment. In this particular application, the GoldSim model consists of a) hydrogeologic model that simulates flow and transport through the Dockum geologic unit that underlies all of the waste facilities, b) waste cells that represent the containment unit and simulate degradation of waste forms, radionuclide leaching, and partitioning into the liquid and vapor phase within the waste unit, c) a cover system model that simulates upward diffusive transport from the underground repository to the atmosphere. In

Performance Assessment Monitoring Plan for the Hanford Site Low-Level Burial Grounds

International Nuclear Information System (INIS)

2006-01-01

The U.S. Department of Energy Order 435.1, Radioactive Waste Management, requires a disposal authorization statement authorizing operation (or continued operation) for low-level waste disposal facilities. In fulfillment of these requirements, a disposal authorization statement was issued on October 25, 1999, authorizing the Hanford Site to transfer, receive, possess, and dispose of low-level radioactive waste at the 200 East Area burial grounds and the 200 West Area burial grounds. One of the conditions is that monitoring plans for the 200 East Area and 200 West Area low-level burial grounds be written and approved by the Richland Operations Office. As a result of a record of decision for the Hanford Site Solid Waste Program and acceptance of the Hanford Site Solid Waste Environmental Impact Statement, the use of the low-level burial ground (LLBG) as a disposal facility for low-level and mixed low-level wastes has been restricted to lined trenches and the Navy reactor-compartment trench only. Hence, as of July 2004, only the two lined trenches in burial ground 218-W-5 (trenches 31 and 34, see Appendix A) and the Navy reactor-compartment trench in burial ground 218 E 12B (trench 94) are allowed to receive waste. When the two lined trenches are filled, the LLBG will cease to operate except for reactor compartment disposal at trench 94. Remaining operational lifetime of the LLBG is dependent on waste volume disposal rates. Existing programs for air sampling and analyses and subsidence monitoring are currently adequate for performance assessment at the LLBG. The waste disposal authorization for the Hanford Site is based (in part) on the post-closure performance assessments for the LLBG. In order to maintain a useful link between operational monitoring (e.g., Resource Conservation and Recovery Act [RCRA], Comprehensive Environmental Response, Compensation, and Liability Act, and State Waste Discharge Permits), constituents, monitoring frequencies, and boundaries require

Maintenance Plan for the Performance Assessments and Composite Analyses of the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site

International Nuclear Information System (INIS)

Vefa Yucel

2007-01-01

U.S. Department of Energy (DOE) Manual M 435.1-1 requires that performance assessments (PAs) and composite analyses (CAs) for low-level waste (LLW) disposal facilities be maintained by the field offices. This plan describes the activities performed to maintain the PA and the CA for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) at the Nevada Test Site (NTS). This plan supersedes the Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site (DOE/NV/11718--491-REV 1, dated September 2002). The plan is based on U.S. Department of Energy (DOE) Order 435.1 (DOE, 1999a), DOE Manual M 435.1-1 (DOE, 1999b), the DOE M 435.1-1 Implementation Guide DOE G 435.1-1 (DOE, 1999c), and the Maintenance Guide for PAs and CAs (DOE, 1999d). The plan includes a current update on PA/CA documentation, a revised schedule, and a section on Quality Assurance

Second performance assessment iteration of the Greater Confinement Disposal facility at the Nevada Test Site

International Nuclear Information System (INIS)

Baer, T.A.; Emery, J.N.; Price, L.L.; Olague, N.E.

1994-04-01

The Greater Confinement Disposal (GCD) facility was established in Area 5 at the Nevada Test Site for containment of waste inappropriate for shallow land burial. Some transuranic (TRU) waste has been disposed of at the GCD facility, and compliance of this disposal system with EPA regulation 40 CFR 191 must be evaluated. We have adopted an iterative approach in which performance assessment results guide site data collection, which in turn influences the parameters and models used in performance assessment. The first iteration was based upon readily available data, and indicated that the GCD facility would likely comply with 40 CFR 191 and that the downward flux of water through the vadose zone (recharge) had a major influence on the results. Very large recharge rates, such as might occur under a cooler, wetter climate, could result in noncompliance. A project was initiated to study recharge in Area 5 by use of three environmental tracers. The recharge rate is so small that the nearest groundwater aquifer will not be contaminated in less than 10,000 years. Thus upward liquid diffusion of radionuclides remained as the sole release pathway. This second assessment iteration refined the upward pathway models and updated the parameter distributions based upon new site information. A new plant uptake model was introduced to the upward diffusion pathway; adsorption and erosion were also incorporated into the model. Several modifications were also made to the gas phase radon transport model. Plutonium solubility and sorption coefficient distributions were changed based upon new information, and on-site measurements were used to update the moisture content distributions. The results of the assessment using these models indicate that the GCD facility is likely to comply with all sections of 40 CFR 191 under undisturbed conditions

Second performance assessment iteration of the Greater Confinement Disposal facility at the Nevada Test Site

Energy Technology Data Exchange (ETDEWEB)

Baer, T.A.; Emery, J.N. [GRAM, Inc., Albuquerque, NM (United States); Price, L.L. [Science Applications International Corp., Albuquerque, NM (United States); Olague, N.E. [Sandia National Labs., Albuquerque, NM (United States)

1994-04-01

The Greater Confinement Disposal (GCD) facility was established in Area 5 at the Nevada Test Site for containment of waste inappropriate for shallow land burial. Some transuranic (TRU) waste has been disposed of at the GCD facility, and compliance of this disposal system with EPA regulation 40 CFR 191 must be evaluated. We have adopted an iterative approach in which performance assessment results guide site data collection, which in turn influences the parameters and models used in performance assessment. The first iteration was based upon readily available data, and indicated that the GCD facility would likely comply with 40 CFR 191 and that the downward flux of water through the vadose zone (recharge) had a major influence on the results. Very large recharge rates, such as might occur under a cooler, wetter climate, could result in noncompliance. A project was initiated to study recharge in Area 5 by use of three environmental tracers. The recharge rate is so small that the nearest groundwater aquifer will not be contaminated in less than 10,000 years. Thus upward liquid diffusion of radionuclides remained as the sole release pathway. This second assessment iteration refined the upward pathway models and updated the parameter distributions based upon new site information. A new plant uptake model was introduced to the upward diffusion pathway; adsorption and erosion were also incorporated into the model. Several modifications were also made to the gas phase radon transport model. Plutonium solubility and sorption coefficient distributions were changed based upon new information, and on-site measurements were used to update the moisture content distributions. The results of the assessment using these models indicate that the GCD facility is likely to comply with all sections of 40 CFR 191 under undisturbed conditions.

Preliminary environmental site assessments in New York City

International Nuclear Information System (INIS)

Lundy, P.; Gasson, D.R.; Longendyke, S.T.

1991-01-01

Preliminary Environmental Site Assessments are often performed prior to real estate transactions or refinancing. These assessments are typically performed for real estate buyers, sellers and lending institutions. Undertaking a Preliminary Environmental Site Assessment in New York City can often be quite complex and time-consuming. This is due, in part, to the age and density of buildings in the city as well as the myriad of regulatory agencies with jurisdiction over environmental issues. This paper will discuss how environmental assessments are performed with a special emphasis on building in New York City. In includes hazardous wastes management for Radon, PCB's and asbestos

Introduction to radiological performance assessment

International Nuclear Information System (INIS)

Moss, G.

1995-02-01

A radiological performance assessment is conducted to provide reasonable assurance that performance objectives for low-level radioactive waste (LLW) disposal will be met. Beginning in the early stages of development, a radiological performance assessment continues through the operational phase, and is instrumental in the postclosure of the facility. Fundamental differences exist in the regulation of commercial and defense LLW, but the radiological performance assessment process is essentially the same for both. The purpose of this document is to describe that process in a concise and straightforward manner. This document focuses on radiological performance assessment as it pertains to commercial LLW disposal, but is applicable to US Department of Energy sites as well. Included are discussions on performance objectives, site characterization, and how a performance assessment is conducted. A case study is used to illustrate how the process works as a whole. A bibliography is provided to assist in locating additional information

The use of site characterization data in the Nirex 97 performance assessment

International Nuclear Information System (INIS)

Jackson, C.P.; Watson, S.P.

1998-01-01

Over a number of years, Nirex examined the possibility of a deep radioactive waste repository at Sellafield. Extensive site investigations were carried out, using both surface geophysics and a number of deep boreholes. Hydrogeological measurements were carried out over a wide range of length scales. The work culminated in the Nirex 97 performance assessment. The use of the site characterization data in Nirex 97 is described. The hydrogeological data can be divided into two main categories: direct measurements of the hydrogeological properties of the rocks on various length scales, and measurements of 'derived' properties such as groundwater head, salinity and temperature. The former data were used to derive initial values of the effective hydrogeological parameters for use in groundwater flow and transport models on various length scales. In order to do this, it was necessary to relate the measurements to the underlying variability and then upscale from the underlying variability to the length scales of interest. The quantification of the uncertainties, relating these to the available data, formed a major part of the analysis. The models were then calibrated using the second category of data. This led, using a Bayesian approach, to revised characterizations of the uncertainty, which were used in the calculations of repository performance. An important feature of the analysis is the systematic treatment of the uncertainties and their relation to data. When allied to an ongoing evaluation of the suitability of a site for a repository, this enables the key uncertainties to be identified as a focus for future site characterisation work

A strategy for the derivation and use of sorption coefficients in performance assessment calculations for the Yucca Mountain site

International Nuclear Information System (INIS)

Meijer, A.

1990-01-01

The chemical interactions of dissolved radionuclides with mineral surfaces along flowpaths from the proposed repository to the accessible environment around Yucca Mountain constitute one of the potential barriers to radionuclide migration at the site. Our limited understanding of these interactions suggests their details will be complex and will involve control by numerous chemical and physical parameters. It appears unlikely that we will understand all the details of these reactions or obtain all the site data required to evaluate each of them in the time available for site characterization. Yet, performance assessment calculations will require some form of coupling of chemical interaction models will hydrologic flow models for the site. Clearly, strategies will be needed to bound the problem without compromising the reliability of the performance assessment calculations required for site suitability analysis. The main purpose of this paper is to describe such a strategy. 39 refs., 7 figs., 5 tabs

SC-HTGR Performance Impact for Arid Sites

International Nuclear Information System (INIS)

Lommers, L.; Geschwindt, J.; Southworth, F.; Shahrokhi, F.

2014-01-01

The SC-HTGR provides high temperature steam which can support industrial process heat applications as well as high efficiency electricity generation. The increased generating efficiency resulting from using high steam temperature provides greater plant output than lower temperature concepts, and it also reduces the fraction of waste heat which must be rejected. This capability is particularly attractive for sites with little or no water for heat rejection. This high temperature capability provides greater flexibility for these sites, and it results in a smaller performance penalty than for lower temperature systems when dry cooling must be used. The performance of the SC-HTGR for a conventional site with wet cooling is discussed first. Then the performance for arid sites is evaluated. Dry cooling performance is evaluated for both moderately arid sites and very hot sites. Offdesign performance of the dry cooling system under extreme conditions is also considered. Finally, operating strategies are explored for sites where some cooling water may be available but only in very limited quantities. Results of these assessments confirm that the higher operating temperatures of the SC-HTGR are very beneficial for arid sites, providing significant advantages for both gross and net power generation. (author)

Performance assessment

International Nuclear Information System (INIS)

Doe, T.

1985-01-01

The purpose of performance assessment is to show that the repository is expected to serve its stated function - disposing of radioactive waste safely both during operation and for the postclosure period. Performance assessment is a straightforward concept, but its application may be very complicated. The concept of performance assessment has been clarified by the Nuclear Regulatory Commission (NRC) in their Draft Generic Technical Position on Licensing Assessment Methodology for High-Level Waste Geologic Repositories (NRC, 1984). This document has gone a long way toward defining the criteria that the NRC will use to determine whether or not information from site characterization is adequate to meet the regulations of the Nuclear Regulatory Commission and the Environmental Protection Agency (EPA). A favorable determination is required for issuance of a construction authorization, which is the first major regulatory requirement for developing a working repository. It is, therefore, essential that a research program be developed that not only resolves the outstanding technical issues, but also does it in such a way that the results are clearly applicable to the formal performance assessment and licensing procedures. The definitions of performance assessment are reviewed and the current NRC thinking is summarized

Generalized Fragility Relationships with Local Site Conditions for Probabilistic Performance-based Seismic Risk Assessment of Bridge Inventories

Directory of Open Access Journals (Sweden)

Sivathayalan S.

2012-01-01

Full Text Available The current practice of detailed seismic risk assessment cannot be easily applied to all the bridges in a large transportation networks due to limited resources. This paper presents a new approach for seismic risk assessment of large bridge inventories in a city or national bridge network based on the framework of probabilistic performance based seismic risk assessment. To account for the influences of local site effects, a procedure to generate site-specific hazard curves that includes seismic hazard microzonation information has been developed for seismic risk assessment of bridge inventories. Simulated ground motions compatible with the site specific seismic hazard are used as input excitations in nonlinear time history analysis of representative bridges for calibration. A normalizing procedure to obtain generalized fragility relationships in terms of structural characteristic parameters of bridge span and size and longitudinal and transverse reinforcement ratios is presented. The seismic risk of bridges in a large inventory can then be easily evaluated using the normalized fragility relationships without the requirement of carrying out detailed nonlinear time history analysis.

INITIAL SINGLE-SHELL TANK (SST) SYSTEM PERFORMANCE ASSESSMENT OF THE HANFORD SITE

International Nuclear Information System (INIS)

JARAYSI, M.N.

2007-01-01

The ''Initial Single-Shell Tank System Performance Assessment for the Hanford Site [1] (SST PA) presents the analysis of the long-term impacts of residual wastes assumed to remain after retrieval of tank waste and closure of the SST farms at the US Department of Energy (DOE) Hanford Site. The SST PA supports key elements of the closure process agreed upon in 2004 by DOE, the Washington State Department of Ecology (Ecology), and the US Environmental Protection Agency (EPA). The SST PA element is defined in Appendix I of the ''Hanford Federal Facility Agreement and Consent Order'' (HFFACO) (Ecology et al. 1989) [2], the document that establishes the overall closure process for the SST and double-shell tank (DST) systems. The approach incorporated in the SST PA integrates substantive features of both hazardous and radioactive waste management regulations into a single analysis. The defense-in-depth approach used in this analysis defined two major engineering barriers (a surface barrier and the grouted tank structure) and one natural barrier (the vadose zone) that will be relied on to control waste release into the accessible environment and attain expected performance metrics. The analysis evaluates specific barrier characteristics and other site features that influence contaminant migration by the various pathways. A ''reference'' case and a suite of sensitivity/uncertainty cases are considered. The ''reference case'' evaluates environmental impacts assuming central tendency estimates of site conditions. ''Reference'' case analysis results show residual tank waste impacts on nearby groundwater, air resources; or inadvertent intruders to be well below most important performance objectives. Conversely, past releases to the soil, from previous tank farm operations, are shown to have groundwater impacts that re significantly above most performance objectives. Sensitivity/uncertainty cases examine single and multiple parameter variability along with plausible alternatives

Hanford Site Risk Assessment Methodology. Revision 3

International Nuclear Information System (INIS)

1995-05-01

This methodology has been developed to prepare human health and ecological evaluations of risk as part of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) remedial investigations (RI) and the Resource conservation and Recovery Act of 1976 (RCRA) facility investigations (FI) performed at the Hanford Site pursuant to the hanford Federal Facility Agreement and Consent Order (Ecology et al. 1994), referred to as the Tri-Party Agreement. Development of the methodology has been undertaken so that Hanford Site risk assessments are consistent with current regulations and guidance, while providing direction on flexible, ambiguous, or undefined aspects of the guidance. The methodology identifies site-specific risk assessment considerations and integrates them with approaches for evaluating human and ecological risk that can be factored into the risk assessment program supporting the Hanford Site cleanup mission. Consequently, the methodology will enhance the preparation and review of individual risk assessments at the Hanford Site

Postclosure performance assessment of the SCP [Site Characterization Plan] conceptual design for horizontal emplacement: Revision 1

International Nuclear Information System (INIS)

1987-08-01

This report is a preliminary postclosure performance assessment of the repository design specified in the Site Characterization Plan Conceptual Design Report (SCP-CDR) for horizontal emplacement of high-level nuclear waste. At the time that these analyses were done, horizontal emplacement was the preferred orientation for the waste packages but vertical emplacement is now the reference design. This assessment consists of (1) a review of the regulatory requirements and strategy to demonstrate compliance with these requirements, (2) an analysis of the performance of the total repository system, (3) an analysis of the thermomechanical behavior of the repository, (4) an analysis of brine mobility in the repository, (5) an analysis of the waste package performance, (6) an analysis of the performance of seals, and (7) comments on the sensitivity of the various performance measures to uncertainties in the data and models. These are preliminary analyses and, in most cases, involve bounding calculations of the repository behavior. They have several purposes including (1) assessing how well this conceptual design ''measures up'' against requirements, (2) gaining experience in implementing the performance assessment strategy and tools and thereby learning where improvements are needed, (3) helping to identify needed data, and (4) helping to indicate required design modifications. 26 refs., 40 figs., 20 tabs

Hanford Site baseline risk assessment methodology. Revision 2

Energy Technology Data Exchange (ETDEWEB)

1993-03-01

This methodology has been developed to prepare human health and environmental evaluations of risk as part of the Comprehensive Environmental Response, Compensation, and Liability Act remedial investigations (RIs) and the Resource Conservation and Recovery Act facility investigations (FIs) performed at the Hanford Site pursuant to the Hanford Federal Facility Agreement and Consent Order referred to as the Tri-Party Agreement. Development of the methodology has been undertaken so that Hanford Site risk assessments are consistent with current regulations and guidance, while providing direction on flexible, ambiguous, or undefined aspects of the guidance. The methodology identifies Site-specific risk assessment considerations and integrates them with approaches for evaluating human and environmental risk that can be factored into the risk assessment program supporting the Hanford Site cleanup mission. Consequently, the methodology will enhance the preparation and review of individual risk assessments at the Hanford Site.

Site calibration for the wind turbine performance evaluation

International Nuclear Information System (INIS)

Nam, Yoon Su; Yoo, Neung Soo; Lee, Jung Wan

2004-01-01

The accurate wind speed information at the hub height of a wind turbine is very essential to the exact estimation of the wind turbine power performance testing. Several method on the site calibration, which is a technique to estimate the wind speed at the wind turbine's hub height based on the measured wind data using a reference meteorological mast, are introduced. A site calibration result and the wind resource assessment for the TaeKwanRyung test site are presented using three-month wind data from a reference meteorological mast and the other mast temporarily installed at the site of wind turbine. Besides, an analysis on the uncertainty allocation for the wind speed correction using site calibration is performed

Gamma camera performance: technical assessment protocol

International Nuclear Information System (INIS)

Bolster, A.A.; Waddington, W.A.

1996-01-01

This protocol addresses the performance assessment of single and dual headed gamma cameras. No attempt is made to assess the performance of any associated computing systems. Evaluations are usually performed on a gamma camera commercially available within the United Kingdom and recently installed at a clinical site. In consultation with the manufacturer, GCAT selects the site and liaises with local staff to arrange a mutually convenient time for assessment. The manufacturer is encouraged to have a representative present during the evaluation. Three to four days are typically required for the evaluation team to perform the necessary measurements. When access time is limited, the team will modify the protocol to test the camera as thoroughly as possible. Data are acquired on the camera's computer system and are subsequently transferred to the independent GCAT computer system for analysis. This transfer from site computer to the independent system is effected via a hardware interface and Interfile data transfer. (author)

Gamma camera performance: technical assessment protocol

Energy Technology Data Exchange (ETDEWEB)

Bolster, A.A. [West Glasgow Hospitals NHS Trust, London (United Kingdom). Dept. of Clinical Physics; Waddington, W.A. [University College London Hospitals NHS Trust, London (United Kingdom). Inst. of Nuclear Medicine

1996-12-31

This protocol addresses the performance assessment of single and dual headed gamma cameras. No attempt is made to assess the performance of any associated computing systems. Evaluations are usually performed on a gamma camera commercially available within the United Kingdom and recently installed at a clinical site. In consultation with the manufacturer, GCAT selects the site and liaises with local staff to arrange a mutually convenient time for assessment. The manufacturer is encouraged to have a representative present during the evaluation. Three to four days are typically required for the evaluation team to perform the necessary measurements. When access time is limited, the team will modify the protocol to test the camera as thoroughly as possible. Data are acquired on the camera`s computer system and are subsequently transferred to the independent GCAT computer system for analysis. This transfer from site computer to the independent system is effected via a hardware interface and Interfile data transfer. (author).

NRC performance assessment program

International Nuclear Information System (INIS)

Coplan, S.M.

1986-01-01

The U.S. Nuclear Regulatory Commission's (NRC) performance assessment program includes the development of guidance to the U.S. Department of Energy (DOE) on preparation of a license application and on conducting the studies to support a license application. The nature of the licensing requirements of 10 CFR Part 60 create a need for performance assessments by the DOE. The NRC and DOE staffs each have specific roles in assuring the adequacy of those assessments. Performance allocation is an approach for determining what testing and analysis will be needed during site characterization to assure that an adequate data base is available to support the necessary performance assessments. From the standpoint of establishing is implementable methodology, the most challenging performance assessment needed for licensing is the one that will be used to determine compliance with the U.S. Environmental Protection Agency's (EPA) containment requirement

Risky business: Assessing cleanup plans for waste sites

International Nuclear Information System (INIS)

Blaylock, B.

1995-01-01

ORNL was chosen to perform human health and ecological risk assessments for DOE because of its risk assessment expertise. The U.S. Department of Energy's many production and research sites contain radioactive and hazardous wastes. These waste sites pose potential risks to the health and safety of remediation and waste management workers and the public. The risks, however, vary from site to site. Some sites undoubtedly present larger risks than others and should be cleaned up first. However, before the cleanup begins, DOE is required by law to prepare an environmental impact statement on any actions that may significantly affect the environment-even actions that would clean it up

Comments on ''Use of conditional simulation in nuclear waste site performance assessment'' by Carol Gotway

International Nuclear Information System (INIS)

Downing, D.J.

1993-01-01

This paper discusses Carol Gotway's paper, ''The Use of Conditional Simulation in Nuclear Waste Site Performance Assessment.'' The paper centers on the use of conditional simulation and the use of geostatistical methods to simulate an entire field of values for subsequent use in a complex computer model. The issues of sampling designs for geostatistics, semivariogram estimation and anisotropy, turning bands method for random field generation, and estimation of the comulative distribution function are brought out

Savannah River Site - Salt-stone Disposal Facility Performance Assessment Update

International Nuclear Information System (INIS)

Newman, J.L.

2009-01-01

The Savannah River Site (SRS) Salt-stone Facility is currently in the midst of a Performance Assessment revision to estimate the effect on human health and the environment of adding new disposal units to the current Salt-stone Disposal Facility (SDF). These disposal units continue the ability to safely process the salt component of the radioactive liquid waste stored in the underground storage tanks at SRS, and is a crucial prerequisite for completion of the overall SRS waste disposition plan. Removal and disposal of low activity salt waste from the SRS liquid waste system is required in order to empty tanks for future tank waste processing and closure operations. The Salt-stone Production Facility (SPF) solidifies a low-activity salt stream into a grout matrix, known as salt-stone, suitable for disposal at the SDF. The ability to dispose of the low-activity salt stream in the SDF required a waste determination pursuant to Section 3116 of the Ronald Reagan National Defense Authorization Act of 2005 and was approved in January 2006. One of the requirements of Section 3116 of the NDAA is to demonstrate compliance with the performance objectives set out in Subpart C of Part 61 of Title 10, Code of Federal Regulations. The PA is the document that is used to ensure ongoing compliance. (authors)

performance assessment of substation site earthing using fluke ...

African Journals Online (AJOL)

2013-03-01

Mar 1, 2013 ... Earthing is the fundamental requirement for protection in all electrical ... for the performance assessment of this instrument as compare to the conventional system. ... tem and the reference earth at a given operating fre- quency ...

Assessing hospital disaster preparedness: a comparison of an on-site survey, directly observed drill performance, and video analysis of teamwork.

Science.gov (United States)

Kaji, Amy H; Langford, Vinette; Lewis, Roger J

2008-09-01

There is currently no validated method for assessing hospital disaster preparedness. We determine the degree of correlation between the results of 3 methods for assessing hospital disaster preparedness: administration of an on-site survey, drill observation using a structured evaluation tool, and video analysis of team performance in the hospital incident command center. This was a prospective, observational study conducted during a regional disaster drill, comparing the results from an on-site survey, a structured disaster drill evaluation tool, and a video analysis of teamwork, performed at 6 911-receiving hospitals in Los Angeles County, CA. The on-site survey was conducted separately from the drill and assessed hospital disaster plan structure, vendor agreements, modes of communication, medical and surgical supplies, involvement of law enforcement, mutual aid agreements with other facilities, drills and training, surge capacity, decontamination capability, and pharmaceutical stockpiles. The drill evaluation tool, developed by Johns Hopkins University under contract from the Agency for Healthcare Research and Quality, was used to assess various aspects of drill performance, such as the availability of the hospital disaster plan, the geographic configuration of the incident command center, whether drill participants were identifiable, whether the noise level interfered with effective communication, and how often key information (eg, number of available staffed floor, intensive care, and isolation beds; number of arriving victims; expected triage level of victims; number of potential discharges) was received by the incident command center. Teamwork behaviors in the incident command center were quantitatively assessed, using the MedTeams analysis of the video recordings obtained during the disaster drill. Spearman rank correlations of the results between pair-wise groupings of the 3 assessment methods were calculated. The 3 evaluation methods demonstrated

CERCLA site assessment workbook

International Nuclear Information System (INIS)

1994-08-01

This contains comments for each chapter of exercises (in Vol. 1) which illustrate how to conduct site assessments for CERCLA regulation. A through analysis of the exercises is provided so that work and solutions from Vol 1 can be critiqued and comments are also included on the strategy of site assessment whereas the exercises illustrate the principles involved. Covered exercises include the following: A preliminary assessment of a ground water site; waste characteristics and characterization of sources; documentation of observed releases and actual contamination of targets; the strategy of an SI at a surface water site; the soil exposure pathway; the air pathway

2008 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site, Nye County, Nevada: Review of the Performance Assessments and Composite Analyses

Energy Technology Data Exchange (ETDEWEB)

NSTec Environmental Management

2009-03-30

The Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site requires an annual review to assess the adequacy of the Performance Assessments (PAs) and Composite Analyses (CAs) for each of the facilities, with the results submitted annually to U.S. Department of Energy (DOE) Headquarters. The Disposal Authorization Statements for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) also require that such reviews be made and that secondary or minor unresolved issues be tracked and addressed as part of the maintenance plan. The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO) performed an annual review in fiscal year (FY) 2008 by evaluating operational factors and research results that impact the continuing validity of the PAs and CAs. This annual summary report presents data and conclusions from the FY 2008 review, and determines the adequacy of the PAs and CAs. Operational factors (e.g., waste forms and containers, facility design, and waste receipts), closure plans, monitoring results, and research and development (R&D) activities were reviewed to determine the adequacy of the PAs. Likewise, the environmental restoration activities at the Nevada Test Site relevant to the sources of residual radioactive material that are considered in the CAs, the land-use planning, and the results of the environmental monitoring and R&D activities were reviewed to determine the adequacy of the CAs.

2008 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site, Nye County, Nevada: Review of the Performance Assessments and Composite Analyses

International Nuclear Information System (INIS)

2009-01-01

The Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site requires an annual review to assess the adequacy of the Performance Assessments (PAs) and Composite Analyses (CAs) for each of the facilities, with the results submitted annually to U.S. Department of Energy (DOE) Headquarters. The Disposal Authorization Statements for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) also require that such reviews be made and that secondary or minor unresolved issues be tracked and addressed as part of the maintenance plan. The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO) performed an annual review in fiscal year (FY) 2008 by evaluating operational factors and research results that impact the continuing validity of the PAs and CAs. This annual summary report presents data and conclusions from the FY 2008 review, and determines the adequacy of the PAs and CAs. Operational factors (e.g., waste forms and containers, facility design, and waste receipts), closure plans, monitoring results, and research and development (R and D) activities were reviewed to determine the adequacy of the PAs. Likewise, the environmental restoration activities at the Nevada Test Site relevant to the sources of residual radioactive material that are considered in the CAs, the land-use planning, and the results of the environmental monitoring and R and D activities were reviewed to determine the adequacy of the CAs.

Guidance for performing preliminary assessments under CERCLA

Energy Technology Data Exchange (ETDEWEB)

NONE

1991-09-01

EPA headquarters and a national site assessment workgroup produced this guidance for Regional, State, and contractor staff who manage or perform preliminary assessments (PAs). EPA has focused this guidance on the types of sites and site conditions most commonly encountered. The PA approach described in this guidance is generally applicable to a wide variety of sites. However, because of the variability among sites, the amount of information available, and the level of investigative effort required, it is not possible to provide guidance that is equally applicable to all sites. PA investigators should recognize this and be aware that variation from this guidance may be necessary for some sites, particularly for PAs performed at Federal facilities, PAs conducted under EPA`s Environmental Priorities Initiative (EPI), and PAs at sites that have previously been extensively investigated by EPA or others. The purpose of this guidance is to provide instructions for conducting a PA and reporting results. This guidance discusses the information required to evaluate a site and how to obtain it, how to score a site, and reporting requirements. This document also provides guidelines and instruction on PA evaluation, scoring, and the use of standard PA scoresheets. The overall goal of this guidance is to assist PA investigators in conducting high-quality assessments that result in correct site screening or further action recommendations on a nationally consistent basis.

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

Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the NTS

Energy Technology Data Exchange (ETDEWEB)

Vefa Yucel

2007-01-03

U.S. Department of Energy (DOE) Manual M 435.1-1 requires that performance assessments (PAs) and composite analyses (CAs) for low-level waste (LLW) disposal facilities be maintained by the field offices. This plan describes the activities performed to maintain the PA and the CA for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) at the Nevada Test Site (NTS). This plan supersedes the Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site (DOE/NV/11718--491-REV 1, dated September 2002). The plan is based on U.S. Department of Energy (DOE) Order 435.1 (DOE, 1999a), DOE Manual M 435.1-1 (DOE, 1999b), the DOE M 435.1-1 Implementation Guide DOE G 435.1-1 (DOE, 1999c), and the Maintenance Guide for PAs and CAs (DOE, 1999d). The plan includes a current update on PA/CA documentation, a revised schedule, and a section on Quality Assurance.

Site characterization and performance assessment for a low-level radioactive waste management site in the American Southwest

International Nuclear Information System (INIS)

Shott, G.J.; Sully, M.J.; Muller, C.J.; Hammermeister, D.P.; Ginanni, J.M.

1995-01-01

The Area 5 Radioactive Waste Management Site located in southern Nevada, has been used for the disposal of low-level radioactive waste since 1961. The site is located in the Mohave Desert of the American Southwest, an extremely arid region receiving as little as 0.1 m/yr of precipitation. Site characterization studies have measured the physical, hydrologic, and geochemical properties of core samples collected from 10 shallow boreholes and 3 deep boreholes that extend through the unsaturated zone to the uppermost aquifer. Results indicate that the unsaturated zone consists of 240 m of dry alluvial sediments and is remarkably uniform with respect to most physical parameters. Measurements of saturated hydraulic conductivity with depth showed no evidence of trends, layering, or anisotropy. Parameters for hydraulic functions were not highly variable and exhibited little trend with depth. Water potential profiles indicate that water movement in the upper alluvium is upward, except immediately following a precipitation event. Below the evaporative zone, the liquid flux was downward and of the same order of magnitude as the upward thermal vapor flux induced by the geothermal gradient. The extreme climatic conditions at the site reduce or eliminate many radionuclide release and transport mechanisms. Downward transport of radionuclides to the uppermost aquifer appears unlikely under current climatic conditions. Important radionuclide transport pathways appear to be limited to upward diffusion and advection of gases and biologically-mediated transport. Conceptual models of disposal site performance have been developed based on site characterization studies. The limited transport pathways and limited land use potential of the site provide reasonable assurance that regulatory performance objectives can be met

Overview of the Hanford Site Performance Assurance Program

International Nuclear Information System (INIS)

Duncan, M.R.; Billings, M.P.; Delvin, W.L.; Scott, D.D.; Weatherby, J.W.

1991-01-01

This paper reports on a safeguards and security performance assurance program which encompasses the routine and special activities carried out to assure that safeguards and security subsystems and components are operating in a effective and reliable manner. At the Hanford Site, performance assurance involves widely varied activities, e.g., force-on-force exercises, functional testing of security components, and limited scope performance testing of material control and accountability subsystems. These activities belong to one of four categories: performance testing, functional testing, inspection, and preventive maintenance. Using categories has aided in identifying and assessing the relevant contribution each activity makes to the performance assurance program. Efforts have progressed toward incorporating performance assurance activities into the assessment of protection effectiveness required for Master Safeguards and Security Agreement development and its associated verification and validation process

Confidence assessment. Site-descriptive modelling SDM-Site Laxemar

International Nuclear Information System (INIS)

2009-06-01

The objective of this report is to assess the confidence that can be placed in the Laxemar site descriptive model, based on the information available at the conclusion of the surface-based investigations (SDM-Site Laxemar). In this exploration, an overriding question is whether remaining uncertainties are significant for repository engineering design or long-term safety assessment and could successfully be further reduced by more surface-based investigations or more usefully by explorations underground made during construction of the repository. Procedures for this assessment have been progressively refined during the course of the site descriptive modelling, and applied to all previous versions of the Forsmark and Laxemar site descriptive models. They include assessment of whether all relevant data have been considered and understood, identification of the main uncertainties and their causes, possible alternative models and their handling, and consistency between disciplines. The assessment then forms the basis for an overall confidence statement. The confidence in the Laxemar site descriptive model, based on the data available at the conclusion of the surface based site investigations, has been assessed by exploring: - Confidence in the site characterization data base, - remaining issues and their handling, - handling of alternatives, - consistency between disciplines and - main reasons for confidence and lack of confidence in the model. Generally, the site investigation database is of high quality, as assured by the quality procedures applied. It is judged that the Laxemar site descriptive model has an overall high level of confidence. Because of the relatively robust geological model that describes the site, the overall confidence in the Laxemar Site Descriptive model is judged to be high, even though details of the spatial variability remain unknown. The overall reason for this confidence is the wide spatial distribution of the data and the consistency between

Confidence assessment. Site-descriptive modelling SDM-Site Laxemar

Energy Technology Data Exchange (ETDEWEB)

2008-12-15

The objective of this report is to assess the confidence that can be placed in the Laxemar site descriptive model, based on the information available at the conclusion of the surface-based investigations (SDM-Site Laxemar). In this exploration, an overriding question is whether remaining uncertainties are significant for repository engineering design or long-term safety assessment and could successfully be further reduced by more surface-based investigations or more usefully by explorations underground made during construction of the repository. Procedures for this assessment have been progressively refined during the course of the site descriptive modelling, and applied to all previous versions of the Forsmark and Laxemar site descriptive models. They include assessment of whether all relevant data have been considered and understood, identification of the main uncertainties and their causes, possible alternative models and their handling, and consistency between disciplines. The assessment then forms the basis for an overall confidence statement. The confidence in the Laxemar site descriptive model, based on the data available at the conclusion of the surface based site investigations, has been assessed by exploring: - Confidence in the site characterization data base, - remaining issues and their handling, - handling of alternatives, - consistency between disciplines and - main reasons for confidence and lack of confidence in the model. Generally, the site investigation database is of high quality, as assured by the quality procedures applied. It is judged that the Laxemar site descriptive model has an overall high level of confidence. Because of the relatively robust geological model that describes the site, the overall confidence in the Laxemar Site Descriptive model is judged to be high, even though details of the spatial variability remain unknown. The overall reason for this confidence is the wide spatial distribution of the data and the consistency between

Performance Assessment for Pump-and-Treat Closure or Transition

Energy Technology Data Exchange (ETDEWEB)

Truex, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Christian D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Becker, Dave J. [U.S. Army Corps of Engineers Environmental and Munitions Center of Expertise, Huntsville, AL (United States); Lee, Michelle H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Nimmons, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-09-29

A structured performance assessment approach is useful to evaluate pump-and-treat (P&T) groundwater remediation, which has been applied at numerous sites. Consistent with the U.S. Environmental Protection Agency’s Groundwater Road Map, performance assessment during remedy implementation may be needed, and should consider remedy optimization, transition to alternative remedies, or remedy closure. In addition, a recent National Research Council study examined groundwater remediation at complex contaminated sites and concluded that it may be beneficial to evaluate remedy performance and the potential need for transition to alternative approaches at these sites. The intent of this document is to provide a structured approach for assessing P&T performance to support a decision to optimize, transition, or close a P&T remedy. The process presented in this document for gathering information and performing evaluations to support P&T remedy decisions includes use of decision elements to distinguish between potential outcomes of a remedy decision. Case studies are used to augment descriptions of decision elements and to illustrate each type of outcome identified in the performance assessment approach. The document provides references to resources for tools and other guidance relevant to conducting the P&T assessment.

Estimation of natural ground water recharge for the performance assessment of a low-level waste disposal facility at the Hanford Site

International Nuclear Information System (INIS)

Rockhold, M.L.; Fayer, M.J.; Kincaid, C.T.; Gee, G.W.

1995-03-01

In 1994, the Pacific Northwest Laboratory (PNL) initiated the Recharge Task, under the PNL Vitrification Technology Development (PVTD) project, to assist Westinghouse Hanford Company (WHC) in designing and assessing the performance of a low-level waste (LLW) disposal facility for the US Department of Energy (DOE). The Recharge Task was established to address the issue of ground water recharge in and around the LLW facility and throughout the Hanford Site as it affects the unconfined aquifer under the facility. The objectives of this report are to summarize the current knowledge of natural ground water recharge at the Hanford Site and to outline the work that must be completed in order to provide defensible estimates of recharge for use in the performance assessment of this LLW disposal facility. Recharge studies at the Hanford Site indicate that recharge rates are highly variable, ranging from nearly zero to greater than 100 mm/yr depending on precipitation, vegetative cover, and soil types. Coarse-textured soils without plants yielded the greatest recharge. Finer-textured soils, with or without plants, yielded the least. Lysimeters provided accurate, short-term measurements of recharge as well as water-balance data for the soil-atmosphere interface and root zone. Tracers provided estimates of longer-term average recharge rates in undisturbed settings. Numerical models demonstrated the sensitivity of recharge rates to different processes and forecast recharge rates for different conditions. All of these tools (lysimetry, tracers, and numerical models) are considered vital to the development of defensible estimates of natural ground water recharge rates for the performance assessment of a LLW disposal facility at the Hanford Site

Quantifying and visualizing site performance in clinical trials.

Science.gov (United States)

Yang, Eric; O'Donovan, Christopher; Phillips, JodiLyn; Atkinson, Leone; Ghosh, Krishnendu; Agrafiotis, Dimitris K

2018-03-01

One of the keys to running a successful clinical trial is the selection of high quality clinical sites, i.e., sites that are able to enroll patients quickly, engage them on an ongoing basis to prevent drop-out, and execute the trial in strict accordance to the clinical protocol. Intuitively, the historical track record of a site is one of the strongest predictors of its future performance; however, issues such as data availability and wide differences in protocol complexity can complicate interpretation. Here, we demonstrate how operational data derived from central laboratory services can provide key insights into the performance of clinical sites and help guide operational planning and site selection for new clinical trials. Our methodology uses the metadata associated with laboratory kit shipments to clinical sites (such as trial and anonymized patient identifiers, investigator names and addresses, sample collection and shipment dates, etc.) to reconstruct the complete schedule of patient visits and derive insights about the operational performance of those sites, including screening, enrollment, and drop-out rates and other quality indicators. This information can be displayed in its raw form or normalized to enable direct comparison of site performance across studies of varied design and complexity. Leveraging Covance's market leadership in central laboratory services, we have assembled a database of operational metrics that spans more than 14,000 protocols, 1400 indications, 230,000 unique investigators, and 23 million patient visits and represents a significant fraction of all clinical trials run globally in the last few years. By analyzing this historical data, we are able to assess and compare the performance of clinical investigators across a wide range of therapeutic areas and study designs. This information can be aggregated across trials and geographies to gain further insights into country and regional trends, sometimes with surprising results. The

Performance assessment calculational exercises

International Nuclear Information System (INIS)

Barnard, R.W.; Dockery, H.A.

1990-01-01

The Performance Assessment Calculational Exercises (PACE) are an ongoing effort coordinated by Yucca Mountain Project Office. The objectives of fiscal year 1990 work, termed PACE-90, as outlined in the Department of Energy Performance Assessment (PA) Implementation Plan were to develop PA capabilities among Yucca Mountain Project (YMP) participants by calculating performance of a Yucca Mountain (YM) repository under ''expected'' and also ''disturbed'' conditions, to identify critical elements and processes necessary to assess the performance of YM, and to perform sensitivity studies on key parameters. It was expected that the PACE problems would aid in development of conceptual models and eventual evaluation of site data. The PACE-90 participants calculated transport of a selected set of radionuclides through a portion of Yucca Mountain for a period of 100,000 years. Results include analyses of fluid-flow profiles, development of a source term for radionuclide release, and simulations of contaminant transport in the fluid-flow field. Later work included development of a problem definition for perturbations to the originally modeled conditions and for some parametric sensitivity studies. 3 refs

Hanford Site's Integrated Risk Assessment Program: No-intervention risk assessment

International Nuclear Information System (INIS)

Mahaffey, J.A.; Dukelow, J.S. Jr.; Stenner, R.D.

1994-08-01

The long-term goal of the Integrated Risk Assessment program (IRAP) is to estimate risks to workers, the public, organizations, and groups with reserved rights to Site access, the ecosystem, and natural resources to aid in managing environmental restoration and waste management at the Hanford Site. For each of these, information is needed about current risks, risks during cleanup, and endstate risks. The objective is three-fold: to determine if and when to remediate, and to what extent; to identify information unavailable but needed to make better cleanup decisions; to establish technology performance criteria for achieving desired cleanup levels; to understand costs and benefits of activities from a Site-wide perspective. The no-intervention risk, assessment is the initial evaluation of public health risks conducted under IRAP. The objective is to identify types of activities that the US Department of Energy (DOE) must accomplish for closure of the Hanford Site, defined as no further DOE intervention. There are two primary conclusions from the no-intervention risk assessment. First, some maintenance and operations activities at Hanford must be continued to protect the public from grave risks. However, when large Hanford expenditures are compared to cleanup progress, funds expended for maintenance and operations must be put in proper perspective. Second, stakeholder's emphasis on public risks at Hanford, as indicated by remediation priorities, are not in line with those estimated. The focus currently is on compliance with regulations, and on dealing with issues which are visible to stakeholders

Performance Assessment National Review Group

International Nuclear Information System (INIS)

Lieberman, J.A.; Davis, S.N.; Harleman, D.R.F.

1985-02-01

Performance assessment involves predicting the potential radiological impact of a nuclear waste disposal system, taking into account all of the natural and engineered components of the system. It includes the analysis and evaluation of predicted system and component performance to determine compliance with regulatory performance criteria. In the context of the nuclear waste management program, performance assessment has five major purposes: to assist in the evaluation and selection of repository sites; to guide the research, development, and testing programs; to assist in the evaluation of repository designs; to assist in the evaluation of the design and performance of engineered barriers; and to show regulatory compliance and support repository licensing. Current performance assessment methodologies are still in the developmental stage. Only the simplest of bounding calculations have produced quantitative predictions of radionuclide releases. The methodologies require considerable extension and validation before they can provide answers suitable for project decisions and licensing. 135 refs., 9 figs., 1 tab

Building Confidence in LLW Performance Assessments - 13386

Energy Technology Data Exchange (ETDEWEB)

Rustick, Joseph H.; Kosson, David S.; Krahn, Steven L.; Clarke, James H. [Vanderbilt University, Department of Civil and Environmental Engineering and Consortium for Risk Evaluation with Stakeholder Participation, Nashville, Tennessee, 37235 (United States)

2013-07-01

The performance assessment process and incorporated input assumptions for four active and one planned DOE disposal sites were analyzed using a systems approach. The sites selected were the Savannah River E-Area Slit and Engineered Trenches, Hanford Integrated Disposal Facility, Idaho Radioactive Waste Management Complex, Oak Ridge Environmental Management Waste Management Facility, and Nevada National Security Site Area 5. Each disposal facility evaluation incorporated three overall system components (1) site characteristics (climate, geology, geochemistry, etc.), (2) waste properties (waste form and package), and (3) engineered barrier designs (cover system, liner system). Site conceptual models were also analyzed to identity the main risk drivers and risk insights controlling performance for each disposal facility. (authors)

Building Confidence in LLW Performance Assessments - 13386

International Nuclear Information System (INIS)

Rustick, Joseph H.; Kosson, David S.; Krahn, Steven L.; Clarke, James H.

2013-01-01

The performance assessment process and incorporated input assumptions for four active and one planned DOE disposal sites were analyzed using a systems approach. The sites selected were the Savannah River E-Area Slit and Engineered Trenches, Hanford Integrated Disposal Facility, Idaho Radioactive Waste Management Complex, Oak Ridge Environmental Management Waste Management Facility, and Nevada National Security Site Area 5. Each disposal facility evaluation incorporated three overall system components (1) site characteristics (climate, geology, geochemistry, etc.), (2) waste properties (waste form and package), and (3) engineered barrier designs (cover system, liner system). Site conceptual models were also analyzed to identity the main risk drivers and risk insights controlling performance for each disposal facility. (authors)

Performance Assessment Transport Modeling of Uranium at the Area 5 Radioactive Waste Management Site at the Nevada National Security Site

International Nuclear Information System (INIS)

2010-01-01

Following is a brief summary of the assumptions that are pertinent to the radioactive isotope transport in the GoldSim Performance Assessment model of the Area 5 Radioactive Waste Management Site, with special emphasis on the water-phase reactive transport of uranium, which includes depleted uranium products. The Area 5 PA model assumes activity disposed in trenches is well mixed within the native alluvium of the trench at the time the facility is closed. Waste containers and waste forms are assumed not to limit the release of radionuclides for transport. In the Area 5 RWMS PA model, the pathways that are considered to bring radioactivity in the waste zone to the surface soils of the closure covers are (1) plant uptake, (2) burrowing animal activity, and (3) advection/dispersion/diffusion in the pore water. Water-phase transport is a minor component of the transport, which is dominated by plant uptake and burrowing animal activity. Because the soil column is mostly dry, upward water flux rates are extremely small, resulting in small advective/dispersive transport of radioactive isotopes in pore water of the unsaturated zone. Reactive transport of radioactive elements in the Area 5 soil pore water are modeled using element-specific partition coefficients (Kds) that partition radioactivity between pore water and soil of the disposal cell, and solubility limits that control the solubility of elements in pore water. Geochemical modeling is not performed in the Area 5 RWMS GoldSim PA model; however, Kds and solubility limits were derived from previous geochemical modeling performed using Area 5 geochemical data. Kds for uranium were developed based on geochemical modeling using the mineral characteristics of soil (alluvium) and the chemical characteristics of water at the site (Carle et al., 2002). In the GoldSim model, uranium Kd is represented with a lognormal distribution with a mean value of 0.8 milliliter per gram (taken from Figure 4.11, Page 4-19 of Carle et al

Binding-site assessment by virtual fragment screening.

Directory of Open Access Journals (Sweden)

Niu Huang

2010-04-01

Full Text Available The accurate prediction of protein druggability (propensity to bind high-affinity drug-like small molecules would greatly benefit the fields of chemical genomics and drug discovery. We have developed a novel approach to quantitatively assess protein druggability by computationally screening a fragment-like compound library. In analogy to NMR-based fragment screening, we dock approximately 11,000 fragments against a given binding site and compute a computational hit rate based on the fraction of molecules that exceed an empirically chosen score cutoff. We perform a large-scale evaluation of the approach on four datasets, totaling 152 binding sites. We demonstrate that computed hit rates correlate with hit rates measured experimentally in a previously published NMR-based screening method. Secondly, we show that the in silico fragment screening method can be used to distinguish known druggable and non-druggable targets, including both enzymes and protein-protein interaction sites. Finally, we explore the sensitivity of the results to different receptor conformations, including flexible protein-protein interaction sites. Besides its original aim to assess druggability of different protein targets, this method could be used to identifying druggable conformations of flexible binding site for lead discovery, and suggesting strategies for growing or joining initial fragment hits to obtain more potent inhibitors.

Site remediation guided by risk assessment

International Nuclear Information System (INIS)

McBean, E.A.; Gowing, A.; Pieczonka, G.

2002-01-01

'Full text:' Risk assessment (RA) provides an effective tool for identifying hazards with respect to human health and ecological receptors, hazards that arise from contaminants in the environment. Risk assessment relies upon: hazard identification/problem formulation; toxicity assessment; exposure assessment; and risk characterization. Hence, risk assessment provides an effective guide for site remediation through the identification of the associated risks arising from pre- and potential post-remediation activities. As a demonstration of this decision-making process, a site-specific risk assessment (SSRA) was performed on a chemical producing facility. Historical waste practices during the production of DDT compounds resulted in impacted site soils and sediment and soils of the creek passing through the facility. The purpose of the SSRA was to derive site-specific cleanup values for the impacted on-site soils, creek sediments, and embankment soils, incorporating human and ecological receptors associated with the environmental media. The human exposure pathways considered were dermal contact, incidental ingestion, and inhalation of the various soils. The potential human receptors were industrial workers, construction workers, trespassers, and off-site residents. Ingestion of fish from the creek by residents was also evaluated in the human health risk assessment (HHRA). Food web analyses were used to evaluate the impact of exposure to chemical compounds in aquatic sediments and related soils by ecological receptors such as the great blue heron, raccoon, and mink. The SSRA involved modelling the daily chemical intake by receptors and the transfer of chemicals to identified secondary media (e.g., ambient air or animal tissues) that are also potential exposure media. These models, while using the site-specific chemical data in the source media, possess uncertainties associated with default parameters that are only approximations and not site-specific (e.g., soil

CERCLA site assessment workbook, Volume 1

International Nuclear Information System (INIS)

1994-08-01

This workbook provides instructions for planning, implementing, and reporting site assessments under CERCLA, commonly referred to as Superfund. Site assessment consists of two information-gathering steps: the remedial preliminary assessment (PA) and the site inspection (SI). The information obtained is then used to estimate, or score, a site's relative risk to public health and the environment. The score is derived via the hazard ranking system (HRS). Although the workbook and its exercises can be adapted to group study, it is designed primarily for use by an individual

Effective gasoline site assessment using the D TECH trademark BTEX immunoassay

International Nuclear Information System (INIS)

Hudak, R.T.; Melby, J.M.; Stave, J.W.

1994-01-01

The application of immunoassay to environmental testing can greatly aid in assessing sites for various contaminants including PCB, TNT, RDX, PAH and BTEX. Immunoassay offers several benefits to site assessment: it is accurate, reproducible and relatively inexpensive compared to instrumental analysis. In addition, because of its ease-of-use, this technique is ideal for the field and requires minimal user training. To demonstrate not only the effectiveness of the BTEX immunoassay, but also the reliability of the field results, a gasoline contaminated site was assessed comparing the BTEX immunoassay to gas chromatography. All sampling and site related activities were executed in accordance to the USEPA SW-846 guidelines. Three (3) analyses were performed on each sample. One immunoassay analysis was performed in the field by an individual who received two (2) hours of training prior to the start of the study. A technician familiar with the immunoassay ran the second analysis in a laboratory. Finally, an independent GC laboratory certified for BTEX method 8020 and 602 performed the GC analyses. One hundred one (101) samples were analyzed: thirty-nine (39) samples were water, the other sixty-two (62) were soils ranging from clay to silt. The results and costs of the methods are compared

Stochastic hydrogeologic units and hydrogeologic properties development for total-system performance assessments. Yucca Mountain Site Characterization Project

International Nuclear Information System (INIS)

Schenker, A.R.; Guerin, D.C.; Robey, T.H.; Rautman, C.A.; Barnard, R.W.

1995-09-01

A stochastic representation of the lithologic units and associated hydrogeologic parameters of the potential high-level nuclear waste repository are developed for use in performance-assessment calculations, including the Total-System Performance Assessment for Yucca Mountain-SNL Second Iteration (TSPA-1993). A simplified lithologic model has been developed based on the physical characteristics of the welded and nonwelded units at Yucca Mountain. Ten hydrogeologic units are developed from site-specific data (lithologic and geophysical logs and core photographs) obtained from the unsaturated and saturated zones. The three-dimensional geostatistical model of the ten hydrogeologic units is based on indicator-coding techniques and improves on the two-dimensional model developed for TSPA91. The hydrogeologic properties (statistics and probability distribution functions) are developed from the results of laboratory tests and in-situ aquifer tests or are derived through fundamental relationships. Hydrogeologic properties for matrix properties, bulk conductivities, and fractures are developed from existing site specific data. Extensive data are available for matrix porosity, bulk density, and matrix saturated conductivity. For other hydrogeologic properties, the data are minimal or nonexistent. Parameters for the properties are developed as beta probability distribution functions. For the model units without enough data for analysis, parameters are developed as analogs to existing units. A relational, analytic approach coupled with bulk conductivity parameters is used to develop fracture parameters based on the smooth-wall-parallel-plate theory. An analytic method is introduced for scaling small-core matrix properties to the hydrogeologic unit scales

Site-Specific Analyses for Demonstrating Compliance with 10 CFR 61 Performance Objectives - 12179

Energy Technology Data Exchange (ETDEWEB)

Grossman, C.J.; Esh, D.W.; Yadav, P.; Carrera, A.G. [U.S. Nuclear Regulatory Commission, 11545 Rockville Pike, Rockville, MD 20852 (United States)

2012-07-01

The U.S. Nuclear Regulatory Commission (NRC) is proposing to amend its regulations at 10 CFR Part 61 to require low-level radioactive waste disposal facilities to conduct site-specific analyses to demonstrate compliance with the performance objectives in Subpart C. The amendments would require licensees to conduct site-specific analyses for protection of the public and inadvertent intruders as well as analyses for long-lived waste. The amendments would ensure protection of public health and safety, while providing flexibility to demonstrate compliance with the performance objectives, for current and potential future waste streams. NRC staff intends to submit proposed rule language and associated regulatory basis to the Commission for its approval in early 2012. The NRC staff also intends to develop associated guidance to accompany any proposed amendments. The guidance is intended to supplement existing low-level radioactive waste guidance on issues pertinent to conducting site-specific analyses to demonstrate compliance with the performance objectives. The guidance will facilitate implementation of the proposed amendments by licensees and assist competent regulatory authorities in reviewing the site-specific analyses. Specifically, the guidance provides staff recommendations on general considerations for the site-specific analyses, modeling issues for assessments to demonstrate compliance with the performance objectives including the performance assessment, intruder assessment, stability assessment, and analyses for long-lived waste. This paper describes the technical basis for changes to the rule language and the proposed guidance associated with implementation of the rule language. The NRC staff, per Commission direction, intends to propose amendments to 10 CFR Part 61 to require licensees to conduct site-specific analyses to demonstrate compliance with performance objectives for the protection of public health and the environment. The amendments would require a

Use of Historical Pump-and-Treat Data to Enhance Site Characterization and Remediation Performance Assessment.

Science.gov (United States)

Brusseau, Mark L

2013-10-01

Groundwater withdrawal and contaminant concentration data are routinely collected for pump-and-treat operations conducted at hazardous waste sites. These data sets can be mined to produce a wealth of information to support enhanced site characterization, optimization of remedial system operations, and improved decision making regarding long-term site management and closure. Methods that may be used to analyze and interpret pump-and-treat data to produce such assessments are presented, along with a brief illustration of their application to a site. The results presented herein illustrate that comprehensive analysis of pump-and-treat data is a powerful, cost-effective method for providing higher-resolution, value-added characterization of contaminated sites.

Performance assessment review for DOE LLW disposal facilities

International Nuclear Information System (INIS)

Wilhite, Elmer L.

1992-01-01

assessments. These lessons are shared among the various US DOE sites to improve the process of evaluating low-level waste disposal sites for long-term performance. (author)

Conceptual, experimental and computational approaches to support performance assessment of hydrology and chemical transport at Yucca Mountain; Yucca Mountain Site Characterization Project

Energy Technology Data Exchange (ETDEWEB)

Narasimhan, T.N.; Wang, J.S.Y. [Lawrence Berkeley Lab., CA (United States)

1992-07-01

The authors of this report have been participating in the Sandia National Laboratory`s hydrologic performance assessment of the Yucca Mountain, Nevada, since 1983. The scope of this work is restricted to the unsaturated zone at Yucca Mountain and to technical questions about hydrology and chemical transport. The issues defined here are not to be confused with the elaborate hierarchy of issues that forms the framework of the US Department of Energy plans for characterizing the site (DOE, 1989). The overall task of hydrologic performance assessment involves issues related to hydrology, geochemistry, and energy transport in a highly heterogeneous natural geologic system which will be perturbed in a major way by the disposal activity. Therefore, a rational evaluation of the performance assessment issues must be based on an integrated appreciation of the aforesaid interacting processes. Accordingly, a hierarchical approach is taken in this report, proceeding from the statement of the broad features of the site that make it the site for intensive studies and the rationale for disposal strategy, through the statement of the fundamental questions that need to be answered, to the identification of the issues that need resolution. Having identified the questions and issues, the report then outlines the tasks to be undertaken to resolve the issues. The report consists essentially of two parts. The first part deals with the definition of issues summarized above. The second part summarizes the findings of the authors between 1983 and 1989 under the activities of the former Nevada Nuclear Waste Storage Investigations (NNWSI) and the current YMP.

Context for performance assessment

International Nuclear Information System (INIS)

Kocher, D.C.

1997-01-01

In developing its recommendations on performance assessment for disposal of low-level radioactive waste, Scientific committee 87-3 of the National Council on Radiation Protection and Measurements (NCRP) has considered a number of topics that provide a context for the development of suitable approaches to performance assessment. This paper summarizes the Committee' discussions on these topics, including (1) the definition of low-level waste and its sources and properties, as they affect the variety of wastes that must be considered, (2) fundamental objectives and principles of radioactive waste disposal and their application to low-level waste, (3) current performance objectives for low-level waste disposal in the US, with particular emphasis on such unresolved issues of importance to performance assessment as the time frame for compliance, requirements for protection of groundwater and surface water, inclusion of doses from radon, demonstrating compliance with fixed performance objectives using highly uncertain model projections, and application of the principle that releases to the environment should be maintained as low as reasonably achievable (ALARA), (4) the role of active and passive institutional controls over disposal sites, (5) the role of the inadvertent human intruder in low-level waste disposal, (6) model validation and confidence in model outcomes, and (7) the concept of reasonable assurance of compliance

Performance assessment for low-level waste disposal in the UK

Energy Technology Data Exchange (ETDEWEB)

Ashworth, A.B. [UK Dept. of the Environment, London (United Kingdom)

1995-12-31

British Nuclear Fuels plc (BNFL) operate a site for the disposal of Low Level Radioactive Waste at Drigg in West Cumbria, in North-West England. HMIP are responsible for the regulation of the site with regard to environmental discharges of radioactive materials, both operational and post-closure. This paper is concerned with post-closure matters only. Two post-closure performance assessments have been carried out for this site: one by the National Radiological Protection Board (NRPB) in 1987; and a subsequent one carried out on behalf of HMIP, completed in 1991. Currently, BNFL are preparing a Safety Case for continued operation of the Drigg site, and it expected that the core of this Case will comprise BNFL`s own analysis of post-closure performance. HMIP has developed procedures for the assessment of this Case, based upon experience of the previous Drigg assessments, and also upon the experience of similar work carried out in the assessment of Intermediate Level Waste (ILW) disposal at both deep and shallow potential sites. This paper describes the more important features of these procedures.

The use of chemical and radionuclide risk estimates in site performance evaluation of mixed waste sites

International Nuclear Information System (INIS)

Till, J.E.; Meyer, K.R.

1988-01-01

Many radioactive waste sites contain not only radioactive material but also varying amounts of chemical waste. The use of such procedures implies some risk at any exposure level, and thus requires that an exposure level be determined that corresponds to an acceptable risk to an individual or a population. Although the uncertainties and limitations of these methods are of concern, the assumption has been generally adopted that the human dose response for all carcinogens is linear, with no threshold occurring at low levels of exposure. With the move toward decontamination programs and clean-up of various mixed waste sites throughout the US, there is interest in the possibility that risk estimates calculated individually for radionuclides and for chemicals may be combined to reflect the total risk for each site. The purpose of this paper is to examine the feasibility of combining risk estimates during risk/benefit analyses. For a variety of reasons, the state of radiation risk assessment is more advanced than that of chemical risk assessment. The reasons for this disparity are summarized in this paper. Quantitative radiation risk assessment is currently being performed, but involves a high degree of uncertainty. Chemical risk assessment in general does not allow quantitative results bracketed by uncertainty analysis. Therefore, it is concluded that it is currently not possible to develop a useful, quantitative combined risk assessment for a mixed waste site, but that it may be possible to develop such a capability in the future

Site descriptions for preliminary radiological assessments of low-level waste repositories

International Nuclear Information System (INIS)

Burgess, W.E.; Jones, C.H.; Sumerling, T.J.; Ashton, J.

1988-07-01

The environmental contexts of four sites, previously under investigation by UK Nirex Ltd. as potential locations for low-level waste disposal facilities, are described. Information on geographical setting, climate, surface hydrology, land use, agriculture, fisheries, geology and hydrogeology is presented. The geological and hydrogeological data are interpreted with the support of deterministic modelling of groundwater conditions. The routes by which radionuclides may migrate from the site are identified and reduced to 1D statistical descriptions suitable for use in probabilistic risk assessments. Additional data required to improve the assessment of the performance of the site are identified. (author)

Environmental assessment, Richton Dome site, Mississippi

International Nuclear Information System (INIS)

1986-05-01

The Nuclear Waste Policy Act of 1982 (42 USC Sections 10101-10226) requires the environmental assessment of a potential site to include a statement of the basis for the nomination of a site as suitable for characterization. Volume 2 of this environmental assessment provides a detailed evaluation of the Richton Dome Site and its suitability as the site for a radioactive waste disposal facility under DOE siting guidelines, as well as a comparison of the Richton Dome site with other proposed sites. Evaluation of the Richton Dome site is based on the reference repository design, but the evaluation will not change if based on the Mission Plan repository concept. The comparative evaluation of proposed sites is required under DOE guidelines, but is not intended to directly support the subsequent recommendation of three sites for characterization as candidate sites. 428 refs., 24 figs., 62 tabs

Coordinated site characterization and performance assessment - an iterative approach for the site evaluation

International Nuclear Information System (INIS)

Papp, T.; Ericsson, L.O.; Thegerstroem, C.; Almen, K.E.

1995-01-01

SKB planning for siting a deep repository involves feasibility studies in 5-10 municipalities surface based characterization and drilling on two candidate sites and detailed characterization of one site including a shaft to proposed repository depth. The selection of a site or the detailed layout of the repository defines characteristics that might influence safety in a broad sense. There is a strong ling between the safety, technical (engineering) and functional aspects. The site selection will be based on general geoscientific information, i.e. mechanical stability, ground-water chemistry, slow ground-water movements and complicating factors like high potential for mineralization. The general layout of the repository in the actual geological structure of the site must be done with regard to a number of guidelines, e.g. to hydraulically separate the parts of the repository containing the spent nuclear fuel from those for other types of long lived waste and to separate the two stages of the spent fuel repository so they can be handled separately in the licensing process. When the various parts of the repository have been tentatively located the consequence of the multiple barrier principle is that the layout of the various parts should be made with the aim to utilize the available natural barrier system at the site as well as possible. (authors). 2 refs., 3 figs., 2 tabs

Remotely operated excavator needs assessment/site visit summary

Energy Technology Data Exchange (ETDEWEB)

Straub, J.; Haller, S.; Worsley, R. [Westinghouse Environmental Management Co. of Ohio, Cincinnati, OH (United States); King, M. [THETA Technology Inc. (United States)

1992-12-02

The Uranium in Soils Integrated Demonstration requested an assessment of soil excavation needs relative to soil remediation. The following list identifies the DOE sites assessed: Mound Laboratory, Paducah Gaseous Diffusion Plant, Portsmouth Gaseous Diffusion Plant, Nevada Test Site, Lawrence Livermore National Laboratory, Rocky Flats Plant, Los Alamos National Laboratory, Sandia National Laboratory, Idaho National Engineering Laboratory, Hanford Site, and Fernald Site. The reviewed sites fall into one or more of the following three categories: production, EPA National Priorities List, or CERCLA (superfund) designation. Only three of the sites appear to have the need for a remotely operated excavator rope. Hanford and Idaho Falls have areas of high-level radioactive contamination either buried or in/under buildings. The Fernald site has a need for remote operated equipment of different types. It is their feeling that remote equipment can be used to remove the health dangers to humans by removing them from the area. Most interviewees stated that characterization technologies needs are more immediate concern over excavation. In addition, the sites do not have similar geographic conditions which would aid in the development of a generic precision excavator. The sites visited were not ready to utilize or provide the required design information necessary to draft a performance specification. This creates a strong case against the development of one type of ROPE for use at these sites. Assuming soil characterization technology/methodology is improved sufficiently to allow accurate and real time field characterization then development of a precision excavator might be pursued based on FEMP needs, since the FEMP`s sole scope of work is remediation. The excavator could then be used/tested and then later modified for other sites as warranted.

Some viewpoints on reference biospheres in Finnish performance assessments

International Nuclear Information System (INIS)

Rasilainen, K.; Kattilakoski, E.; Suolanen, V.; Vieno, T.; Vuori, S.

2002-01-01

Viewpoints are presented concerning biosphere studies in performance assessments of nuclear waste disposal. The points are based on experiences from several Finnish performance assessments. The latest performance assessment for spent fuel disposal, TILA-99, was considered in the Decision in Principle process for the site selection of the repository. The points given are also based on experiences from participation in international projects dealing with biosphere modelling, for instance BIOMOVS and BIOMASS. (author)

Risk assessment-led characterisation of the SiteChar UK north sea site for the geological storage of CO2

International Nuclear Information System (INIS)

Akhurst, Maxine; Hannis, Sarah D.; Quinn, Martyn F.; Long, David; Shi, Ji-Quan; Koenen, Marielle; Pluymaekers, Maarten; Delprat-Jannaud, Florence; Lecomte, Jean-Claude; Bossie-Codreanu, Daniel; Nagy, Stanislaw; Klimkowski, Lukas; Gei, Davide

2015-01-01

Risk assessment-led characterisation of a site for the geological storage of CO 2 in the UK northern North Sea was performed for the EU SiteChar research project as one of a portfolio of sites. Implementation and testing of the SiteChar project site characterisation work-flow has produced a 'dry-run' storage permit application that is compliant with regulatory requirements. A site suitable for commercial-scale storage was characterised, compatible with current and future industrial carbon dioxide (CO 2 ) sources in the northern UK. Pre-characterisation of the site, based on existing information acquired during hydrocarbon exploration and production, has been achieved from publicly available data. The project concept is to store captured CO 2 at a rate of 5 Mt per year for 20 years in the Blake Oil Field and surrounding Captain Sandstone saline aquifer. This commercial-scale storage of 100 Mt CO 2 can be achieved through a storage scenario combining injection of CO 2 into the oil field and concurrent water production down-dip of the field. There would be no encroachment of supercritical phase CO 2 for more than two kilometres beyond the field boundary and no adverse influence on operating hydrocarbon fields provided there is pressure management. Components of a storage permit application for the site are presented, developed as far as possible within a research project. Characterisation and technical investigations were guided by an initial assessment of perceived risks to the prospective site and a need to provide the information required for the storage permit application. The emphasis throughout was to reduce risks and uncertainty on the subsurface containment of stored CO 2 , particularly with respect to site technical performance, monitoring and regulatory issues, and effects on other resources. The results of selected risk assessment-led site characterisation investigations and the subsequent risk reassessments are described together with their

Performance assessment for low-level radioactive waste disposal

International Nuclear Information System (INIS)

Cook, J.R.; Hsu, R.H.; Wilhite, E.L.; Yu, A.D.

1996-01-01

In October 1994 the Savannah River Site became the first US DOE complex to use concrete vaults to dispose of low-level radioactive solid waste and better prevent soil and groundwater contamination. This article describes the design and gives a performance assessment of the vaults. Topics include the following: Performance objectives; scope; the performance assessment process-assemble a multidisciplinary working group; collect available data; define credible pathways/scenarios; develop conceptual models; conduct screening and detailed model calculations; assess sensitivity/uncertainty; integrate and interpret results; report. 9 figs., 3 tabs

TSPA 1991: An initial total-system performance assessment for Yucca Mountain; Yucca Mountain Site Characterization Project

Energy Technology Data Exchange (ETDEWEB)

Barnard, R.W.; Wilson, M.L.; Dockery, H.A.; Kaplan, P.G.; Eaton, R.R.; Bingham, F.W. [Sandia National Labs., Albuquerque, NM (United States); Gauthier, J.H.; Robey, T.H. [Spectra Research Inst., Albuquerque, NM (United States)

1992-07-01

This report describes an assessment of the long-term performance of a repository system that contains deeply buried highly radioactive waste; the system is assumed to be located at the potential site at Yucca Mountain, Nevada. The study includes an identification of features, events, and processes that might affect the potential repository, a construction of scenarios based on this identification, a selection of models describing these scenarios (including abstraction of appropriate models from detailed models), a selection of probability distributions for the parameters in the models, a stochastic calculation of radionuclide releases for the scenarios, and a derivation of complementary cumulative distribution functions (CCDFs) for the releases. Releases and CCDFs are calculated for four categories of scenarios: aqueous flow (modeling primarily the existing conditions at the site, with allowances for climate change), gaseous flow, basaltic igneous activity, and human intrusion. The study shows that models of complex processes can be abstracted into more simplified representations that preserve the understanding of the processes and produce results consistent with those of more complex models.

Impact of the site specialty of a continuity practice on students' clinical skills: performance with standardized patients.

Science.gov (United States)

Pfeiffer, Carol A; Palley, Jane E; Harrington, Karen L

2010-07-01

The assessment of clinical competence and the impact of training in ambulatory settings are two issues of importance in the evaluation of medical student performance. This study compares the clinical skills performance of students placed in three types of community preceptors' offices (pediatrics, medicine, family medicine) on yearly clinical skills assessments with standardized patients. Our goal was to see if the site specialty impacted on clinical performance. The students in the study were completing a 3-year continuity preceptorship at a site representing one of the disciplines. Their performance on the four clinical skills assessments was compared. There was no significant difference in history taking, physical exam, communication, or clinical reasoning in any year (ANOVA p< or = .05) There was a small but significant difference in performance on a measure of interpersonal and interviewing skills during Years 1 and 2. The site specialty of an early clinical experience does not have a significant impact on performance of most of the skills measured by the assessments.

Performance assessment task team progress report

International Nuclear Information System (INIS)

Wood, D.E.; Curl, R.U.; Armstrong, D.R.; Cook, J.R.; Dolenc, M.R.; Kocher, D.C.; Owens, K.W.; Regnier, E.P.; Roles, G.W.; Seitz, R.R.

1994-05-01

The U.S. Department of Energy (DOE) Headquarters EM-35, established a Performance Assessment Task Team (referred to as the Team) to integrate the activities of the sites that are preparing performance assessments (PAs) for disposal of new low-level waste, as required by Chapter III of DOE Order 5820.2A, open-quotes Low-Level Waste Managementclose quotes. The intent of the Team is to achieve a degree of consistency among these PAs as the analyses proceed at the disposal sites. The Team's purpose is to recommend policy and guidance to the DOE on issues that impact the PAs, including release scenarios and parameters, so that the approaches are as consistent as possible across the DOE complex. The Team has identified issues requiring attention and developed discussion papers for those issues. Some issues have been completed, and the recommendations are provided in this document. Other issues are still being discussed, and the status summaries are provided in this document. A major initiative was to establish a subteam to develop a set of test scenarios and parameters for benchmarking codes in use at the various sites. The activities of the Team are reported here through December 1993

Hanford immobilized low-activity tank waste performance assessment

International Nuclear Information System (INIS)

Mann, F.M.

1998-01-01

The Hanford Immobilized Low-Activity Tank Waste Performance Assessment examines the long-term environmental and human health effects associated with the planned disposal of the vitrified low-level fraction of waste presently contained in Hanford Site tanks. The tank waste is the by-product of separating special nuclear materials from irradiated nuclear fuels over the past 50 years. This waste has been stored in underground single and double-shell tanks. The tank waste is to be retrieved, separated into low and high-activity fractions, and then immobilized by private vendors. The US Department of Energy (DOE) will receive the vitrified waste from private vendors and plans to dispose of the low-activity fraction in the Hanford Site 200 East Area. The high-level fraction will be stored at Hanford until a national repository is approved. This report provides the site-specific long-term environmental information needed by the DOE to issue a Disposal Authorization Statement that would allow the modification of the four existing concrete disposal vaults to provide better access for emplacement of the immobilized low-activity waste (ILAW) containers; filling of the modified vaults with the approximately 5,000 ILAW containers and filler material with the intent to dispose of the containers; construction of the first set of next-generation disposal facilities. The performance assessment activity will continue beyond this assessment. The activity will collect additional data on the geotechnical features of the disposal sites, the disposal facility design and construction, and the long-term performance of the waste. Better estimates of long-term performance will be produced and reviewed on a regular basis. Performance assessments supporting closure of filled facilities will be issued seeking approval of those actions necessary to conclude active disposal facility operations. This report also analyzes the long-term performance of the currently planned disposal system as a basis

Hanford immobilized low-activity tank waste performance assessment

Energy Technology Data Exchange (ETDEWEB)

Mann, F.M.

1998-03-26

The Hanford Immobilized Low-Activity Tank Waste Performance Assessment examines the long-term environmental and human health effects associated with the planned disposal of the vitrified low-level fraction of waste presently contained in Hanford Site tanks. The tank waste is the by-product of separating special nuclear materials from irradiated nuclear fuels over the past 50 years. This waste has been stored in underground single and double-shell tanks. The tank waste is to be retrieved, separated into low and high-activity fractions, and then immobilized by private vendors. The US Department of Energy (DOE) will receive the vitrified waste from private vendors and plans to dispose of the low-activity fraction in the Hanford Site 200 East Area. The high-level fraction will be stored at Hanford until a national repository is approved. This report provides the site-specific long-term environmental information needed by the DOE to issue a Disposal Authorization Statement that would allow the modification of the four existing concrete disposal vaults to provide better access for emplacement of the immobilized low-activity waste (ILAW) containers; filling of the modified vaults with the approximately 5,000 ILAW containers and filler material with the intent to dispose of the containers; construction of the first set of next-generation disposal facilities. The performance assessment activity will continue beyond this assessment. The activity will collect additional data on the geotechnical features of the disposal sites, the disposal facility design and construction, and the long-term performance of the waste. Better estimates of long-term performance will be produced and reviewed on a regular basis. Performance assessments supporting closure of filled facilities will be issued seeking approval of those actions necessary to conclude active disposal facility operations. This report also analyzes the long-term performance of the currently planned disposal system as a basis

An overview of performance assessment methodology

International Nuclear Information System (INIS)

Hongnian Jow

2010-01-01

The definition of performance assessment (PA) within the context of a geologic repository program is a post-closure safety assessment; a system analysis of hazards associated with the facility and the ability of the site and the design of the facility to provide for the safety functions. For the last few decades, PA methodology bas been developed and applied to different waste disposal programs around the world. PA has been used in the safety analyses for waste disposal repositories for low-level waste, intermediate level waste, and high-level waste including spent nuclear fuels. This paper provides an overview of the performance assessment methodology and gives examples of its applications for the Yucca Mountain Project. (authors)

2009 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site, Nye County, Nevada: Review of the Performance Assessments and Composite Analysis

Energy Technology Data Exchange (ETDEWEB)

NSTec Environmental Management

2010-03-15

The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office performed an annual review of the Area 3 and Area 5 Radioactive Wate Management Site (RWMS) Performance Assessments (PAs) and Composite Analyses (CAs) in fiscal year (FY) 2009. This annual summary report presents data and conclusions from the FY 2009 review, and determines the adequacy of the PAs and CAs. Operational factors (e.g., waste forms and containers, facility design, and waste receipts), closure plans, monitoring results, and research and development (R&D) activities were reviewed to determine the adequacy of the PAs. Likewise, the environmental restoration activities at the Nevada Test Site relevant to the sources of residual radioactive material that are considered in the CAs, the land-use planning, and the results of the environmental monitoring and R&D activities were reviewed to determine the adequacy of the CAs.

2009 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site, Nye County, Nevada: Review of the Performance Assessments and Composite Analysis

International Nuclear Information System (INIS)

2010-01-01

The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office performed an annual review of the Area 3 and Area 5 Radioactive Waste Management Site (RWMS) Performance Assessments (PAs) and Composite Analyses (CAs) in fiscal year (FY) 2009. This annual summary report presents data and conclusions from the FY 2009 review, and determines the adequacy of the PAs and CAs. Operational factors (e.g., waste forms and containers, facility design, and waste receipts), closure plans, monitoring results, and research and development (R and D) activities were reviewed to determine the adequacy of the PAs. Likewise, the environmental restoration activities at the Nevada Test Site relevant to the sources of residual radioactive material that are considered in the CAs, the land-use planning, and the results of the environmental monitoring and R and D activities were reviewed to determine the adequacy of the CAs.

Applicability of the Linear Sorption Isotherm Model to Represent Contaminant Transport Processes in Site Wide Performance Assessments

International Nuclear Information System (INIS)

FOGWELL, T.W.; LAST, G.V.

2003-01-01

The estimation of flux of contaminants through the vadose zone to the groundwater under varying geologic, hydrologic, and chemical conditions is key to making technically credible and sound decisions regarding soil site characterization and remediation, single-shell tank retrieval, and waste site closures (DOE 2000). One of the principal needs identified in the science and technology roadmap (DOE 2000) is the need to improve the conceptual and numerical models that describe the location of contaminants today, and to provide the basis for forecasting future movement of contaminants on both site-specific and site-wide scales. The State of Knowledge (DOE 1999) and Preliminary Concepts documents describe the importance of geochemical processes on the transport of contaminants through the Vadose Zone. These processes have been identified in the international list of Features, Events, and Processes (FEPs) (NEA 2000) and included in the list of FEPS currently being developed for Hanford Site assessments (Soler et al. 2001). The current vision for Hanford site-wide cumulative risk assessments as performed using the System Assessment Capability (SAC) is to represent contaminant adsorption using the linear isotherm (empirical distribution coefficient, K d ) sorption model. Integration Project Expert Panel (PEP) comments indicate that work is required to adequately justify the applicability of the linear sorption model, and to identify and defend the range of K d values that are adopted for assessments. The work plans developed for the Science and Technology (S and T) efforts, SAC, and the Core Projects must answer directly the question of ''Is there a scientific basis for the application of the linear sorption isotherm model to the complex wastes of the Hanford Site?'' This paper is intended to address these issues. The reason that well documented justification is required for using the linear sorption (K d ) model is that this approach is strictly empirical and is often

Atmospheric Characterization of the US Offshore Sites and Impact on Turbine Performance (Poster)

Energy Technology Data Exchange (ETDEWEB)

Arora, Dhiraj [Alstom Renewable US LLC; Ehrmann, Robert [Alstom Renewable US LLC; Zuo, Delong [Texas Tech University; Xiao, Jingting [Texas Tech University

2016-10-25

Reliable, long term offshore atmospheric data is critical to development of the US offshore wind industry. There exists significant lack of meteorological, oceanographic, and geological data at potential US offshore sites. Assessment of wind resources at heights in the range of 25-200m is needed to understand and characterize offshore wind turbine performance. Data from the US Department of Energy owned WindSentinel buoy from two US offshore sites and one European site is analyzed. Low Level Jet (LLJ) phenomena and its potential impact on the performance of an offshore wind turbine is investigated.

Hanford low-level tank waste interim performance assessment

International Nuclear Information System (INIS)

Mann, F.M.

1997-01-01

The Hanford Low-Level Tank Waste Interim Performance Assessment examines the long-term environmental and human health effects associated with the disposal of the low-level fraction of the Hanford single and double-shell tank waste in the Hanford Site 200 East Area. This report was prepared as a good management practice to provide needed information about the relationship between the disposal system design and performance early in the disposal system project cycle. The calculations in this performance assessment show that the disposal of the low-level fraction can meet environmental and health performance objectives

Technical challenges in the qualitative ecological risk assessments performed on the Hanford Site operable units

International Nuclear Information System (INIS)

Probasco, K.M.

1994-01-01

Qualitative Risk Assessments (QRAS) have been selected as the method for providing the risk-driver indications for interim, remedial, and cleanup actions for the Hanford Site operable units' ecological risk assessments. This expedited response action path has been developed for the Hanford Site to facilitate time-critical decisions and generate immediate emergency cleanup actions. Tight budgets and aggressive time schedules are a major factor in the development of the QRA process. The QRA is a quick way to find immediate threats and a good precursor to a full risk assessment. However, numerous technical challenges have been identified with the QRA approach. The QRA approach differs from a baseline risk assessment in several ways. The main differences involve the use of data that have previously been gathered from the site, and the development of a ''bias-for-action'' document that would reveal qualitative risks from the contaminants identified at the operable units. Technical challenges concerning the ecological portion of these QRAs have raised questions about using the ORA for decision-making and may have weakened the validity of its use in the established procedural framework. Challenges involving such issues as the extrapolation of the contaminant data, data validation and screening techniques, receptor selections, and the final risk characterization outcome threaten the feasibility of the QRA as a decision-making tool. This discussion provides insight into resolving technical challenges and may be a ''lessons-learned'' device for those interested in the QRA approach. Ultimately, these challenges are proving to be learning tools for scientists, regulators, and ecologists and are identifying the data gaps and research direction for future ecological baseline risk assessments

Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site

International Nuclear Information System (INIS)

V. Yucel

2002-01-01

U.S. Department of Energy (DOE) Order 435.1 requires that performance assessments (PAs) and composite analyses (CAs) for low-level waste (LLW) disposal facilities be maintained by the field offices. This plan describes the activities to be performed in maintaining the Performance Assessment (PA) and Composite Analysis (CA) for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) at the Nevada Test Site (NTS). The Disposal Authorization Statement (DAS) for the continuing operations of a LLW facility at the DOE complex specifies the conditions for operations based on approval of a PA and CA, and requires the facility to implement a maintenance program to assure that these conditions will remain protective of the public health and the environment in the future. The goal of the maintenance program is to provide that assurance. The maintenance process is an iterative one in which changing conditions may result in a revision of PA and CA; the revised PA and CA may impose a different set of conditions for facility operation, closure, and postclosure. The maintenance process includes managing uncertainty, performing annual reviews, submitting annual summary reports to DOE Headquarters (DOE/HQ), carrying out special analyses, and revising the PAs and CAs, if necessary. Management of uncertainty is an essential component of the maintenance program because results of the original PAs and CAs are understood to be based on uncertain assumptions about the conceptual models; the mathematical models and parameters; and the future state of the lands, disposal facilities, and human activities. The annual reviews for the PAs include consideration of waste receipts, facility specific factors, results of monitoring, and results of research and development (R and D) activities. Likewise, results of ongoing R and D, changes in land-use planning, new information on known sources of residual radioactive materials, and identification of new sources may warrant an evaluation to

The role of performance assessment in radioactive waste disposal

International Nuclear Information System (INIS)

Stenhouse, M.J.

1998-01-01

Performance assessment has many applications in the field of radioactive waste management, none more important than demonstrating the suitability of a particular repository system for waste disposal. The role of performance assessment in radioactive waste disposal is discussed with reference to assessments performed in civilian waste management programmes. The process is, however, relevant, and may be applied directly to the disposal of defence-related wastes. When used in an open and transparent manner, performance assessment is a powerful methodology not only for convincing the authorities of the safety of a disposal concept, but also for gaining the wider acceptance of the general public for repository siting. 26 refs

Accident consequence assessment and siting criteria development

International Nuclear Information System (INIS)

Kollas, J.G.

1988-01-01

The methodology developed is based on assessing the average over a large spectrum of meteorological conditions whole body collective dose resulting from a severe reference accident. The assessment of this dose is performed by code CRAC.GAEC, the Greek A.E.C. version of code CRAC2. The collective dose, which is chosen as a measure of the social radiation risk, is compared to the dose corresponding to a level of social risk encountered historically in energy production as a whole. The outcome of the comparison can be the determination of one or more sectors of acceptable sites for a set of specific conditions considered, such as the reactor characteristics. The present approach was aimed to deal with the problems stemming from the demographic idiomorphy of Greece, where one third of the country's population is concentrated in Athens, with the rest of the country exhibiting small population densities. One of the applications of the methodology developed concerned the identification of acceptable sites near Athens. For these sites the risk from the reference severe accident of a standard reactor to the over three millions inhabitants of Athens is less tan the risk corresponding to the same population that is due to energy production

The Promise, Practice, and State of Planning Tools to Assess Site Vulnerability to Runoff Phosphorus Loss.

Science.gov (United States)

Kleinman, P J A; Sharpley, A N; Buda, A R; Easton, Z M; Lory, J A; Osmond, D L; Radcliffe, D E; Nelson, N O; Veith, T L; Doody, D G

2017-11-01

Over the past 20 yr, there has been a proliferation of phosphorus (P) site assessment tools for nutrient management planning, particularly in the United States. The 19 papers that make up this special section on P site assessment include decision support tools ranging from the P Index to fate-and-transport models to weather-forecast-based risk calculators. All require objective evaluation to ensure that they are effective in achieving intended benefits to protecting water quality. In the United States, efforts have been underway to compare, evaluate, and advance an array of P site assessment tools. Efforts to corroborate their performance using water quality monitoring data confirms previously documented discrepancies between different P site assessment tools but also highlights a surprisingly strong performance of many versions of the P Index as a predictor of water quality. At the same time, fate-and-transport models, often considered to be superior in their prediction of hydrology and water quality due to their complexity, reveal limitations when applied to site assessment. Indeed, one consistent theme from recent experience is the need to calibrate highly parameterized models. As P site assessment evolves, so too do routines representing important aspects of P cycling and transport. New classes of P site assessment tools are an opportunity to move P site assessment from general, strategic goals to web-based tools supporting daily, operational decisions. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Consideration of liners and covers in performance assessments

Energy Technology Data Exchange (ETDEWEB)

Phifer, Mark A. [Savannah River National Laboratory, Aiken, SC (United States); Seitz, Robert R. [Savannah River National Laboratory, Aiken, SC (United States); Suttora, Linda C. [USDOE Enviromental Management, Washington, DC (United States)

2014-09-18

On-site disposal cells are in use and being considered at several United States Department of Energy (USDOE) sites as the final disposition for large amounts of waste associated with cleanup of contaminated areas and facilities. These disposal cells are typically regulated by States and/or the U.S. Environmental Protection Agency under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) in addition to having to comply with requirements in DOE Order 435.1, Radioactive Waste Management due to the radioactive waste. The USDOE-Environmental Management Office of Site Restoration formed a working group to foster improved communication and sharing of information for personnel associated with these CERCLA disposal cells and work towards more consistent assumptions, as appropriate, for technical and policy considerations related to CERCLA risk assessments and DOE Order 435.1 performance assessments in support of a Record of Decision and Disposal Authorization Statement, respectively. One of the issues considered by the working group, which is addressed in this report, was how to appropriately consider the performance of covers and liners/leachate collections systems in the context of a DOE Order 435.1 performance assessment (PA). This same information may be appropriate for consideration within CERCLA risk assessments for these facilities. These OSDCs are generally developed to meet hazardous waste (HW) disposal design standards under the Resource Conservation and Recovery Act (RCRA) as well as the DOE Order 435.1 performance based standards for disposal of radioactive waste. To meet the standards for HW, the facilities typically include engineered covers and liner/leachate collection systems. Thus, when considering such facilities in the context of a DOE Order 435.1 PA, there is a need to address the evolution of performance of covers and liner/leachate collection systems in the context of meeting a performance standard considering time

Threshold Assessment: Definition of Acceptable Sites as Part of Site Selection for the Japanese HLW Program

International Nuclear Information System (INIS)

McKenna, S.A.; Wakasugi, Keiichiro; Webb, E.K.; Makino, Hitoshi; Ishihara, Yoshinao; Ijiri, Yuji; Sawada, Atsushi; Baba, Tomoko; Ishiguro, Katsuhiko; Umeki, Hiroyuki

2000-01-01

For the last ten years, the Japanese High-Level Nuclear Waste (HLW) repository program has focused on assessing the feasibility of a basic repository concept, which resulted in the recently published H12 Report. As Japan enters the implementation phase, a new organization must identify, screen and choose potential repository sites. Thus, a rapid mechanism for determining the likelihood of site suitability is critical. The threshold approach, described here, is a simple mechanism for defining the likelihood that a site is suitable given estimates of several critical parameters. We rely on the results of a companion paper, which described a probabilistic performance assessment simulation of the HLW reference case in the H12 report. The most critical two or three input parameters are plotted against each other and treated as spatial variables. Geostatistics is used to interpret the spatial correlation, which in turn is used to simulate multiple realizations of the parameter value maps. By combining an array of realizations, we can look at the probability that a given site, as represented by estimates of this combination of parameters, would be good host for a repository site

Surficial geology and performance assessment for a Radioactive Waste Management Facility at the Nevada Test Site

International Nuclear Information System (INIS)

Snyder, K.E.; Gustafson, D.L.; Huckins-Gang, H.E.; Miller, J.J.; Rawlinson, S.E.

1995-02-01

At the Nevada Test Site, one potentially disruptive scenario being evaluated for the Greater Confinement Disposal (GCD) Facility Performance Assessment is deep post-closure erosion that would expose buried radioactive waste to the accessible environment. The GCD Facility located at the Area 5 Radioactive Waste Management Site (RWMS) lies at the juncture of three alluvial fan systems. Geomorphic surface mapping in northern Frenchman Flat indicates that reaches of these fans where the RWMS is now located have been constructional since at least the middle Quaternary. Mapping indicates a regular sequence of prograding fans with entrenchment of the older fan surfaces near the mountain fronts and construction of progressively younger inset fans farther from the mountain fronts. At the facility, the oldest fan surfaces are of late Pleistocene and Holocene age. More recent geomorphic activity has been limited to erosion and deposition along small channels. Trench and pit wall mapping found maximum incision in the vicinity of the RWMS to be less than 1.5 m. Based on collected data, natural geomorphic processes are unlikely to result in erosion to a depth of more than approximately 2 m at the facility within the 10,000-year regulatory period

Environmental site assessments should include radon gas testing

International Nuclear Information System (INIS)

Nardi, M.A.

1991-01-01

There are two emerging influences that will require radon gas testing as part of many property transfers and most site assessments. These requirements come from lending regulators and state legislatures. Fannie Mae and others have developed environmental investigation guidelines for the purchase of environmentally contaminated real estate. These guidelines include radon gas testing for many properties. Several states have enacted laws that require environmental disclosure forms be prepared to ensure that the parties involved in certain real estate transactions are aware of the environmental liabilities that may come with the transfer of property. Indiana has recently enacted legislation that would require the disclosure of the presence of radon gas on many commercial real estate transactions. With more lenders and state governments likely to follow this trend, radon gas testing should be performed during all property transfers and site assessment to protect the parties involved from any legal liabilities

Use of GIS and 3D Modeling for Development and Conceptualization of a Performance Assessment Model for Decommissioning of a Complex Site

International Nuclear Information System (INIS)

Esh, D. W.; Gross, A. J.; Thaggard, M.

2006-01-01

Geographic Information Systems (GIS) and 3D geo-spatial modeling were employed to facilitate development and conceptualization of a performance assessment (PA) model that will be used to evaluate the health impacts of residual radioactivity at a former nuclear materials processing facility site in New York. Previous operations have resulted in a number of different sources of radiological contamination that must be assessed during site decommissioning. A performance assessment model is being developed to estimate radiological dose to potential receptors through the simulation of the release and transport of radionuclides, and exposure to residual contamination for hundreds to thousands of years in the future. A variety of inputs are required to parameterize the performance assessment model, such as: distance from the waste to surface water bodies, thickness of geologic units for saturated transport, saturated thickness of the geologic units, and spatial and temporal average of percent of waste that is saturated. GIS and 3D modeling are used to analyze and abstract aleatory uncertainty associated with the dimensionality of the geologic system into epistemic uncertainty for one- and two-dimensional process models for flow and transport of radionuclides. Three-dimensional geo-spatial modeling was used to develop the geologic framework and the geometrical representation of the residual contamination within the geologic framework. GIS was used in the initial development and parameterization of the transport pathways, to provide spatial context to the PA model, and to link it to the 3D geologic framework and contamination geometry models. Both the GIS and 3-D modeling were used to interpret the results of runs of the PA model. (authors)

Software Quality Assurance Plan for GoldSim Models Supporting the Area 3 and Area 5 Radioactive Waste Management Site Performance Assessment Program

International Nuclear Information System (INIS)

Gregory J. Shott, Vefa Yucel

2007-01-01

This Software Quality Assurance Plan (SQAP) applies to the development and maintenance of GoldSim models supporting the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) performance assessments (PAs) and composite analyses (CAs). Two PA models have been approved by the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office (NNSA/NSO) as of November 2006 for the PA maintenance work undertaken by National Security Technologies, LLC (NSTec). NNSA/NSO asked NSTec to assume the custodianship of the models for future development and maintenance. The models were initially developed by Neptune and Company (N and C)

Software Quality Assurance Plan for GoldSim Models Supporting the Area 3 and Area 5 Radioactive Waste Management Sites Performance Assessment Program

Energy Technology Data Exchange (ETDEWEB)

Gregory J. Shott, Vefa Yucel

2007-01-03

This Software Quality Assurance Plan (SQAP) applies to the development and maintenance of GoldSim models supporting the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) performance assessments (PAs) and composite analyses (CAs). Two PA models have been approved by the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office (NNSA/NSO) as of November 2006 for the PA maintenance work undertaken by National Security Technologies, LLC (NSTec). NNSA/NSO asked NSTec to assume the custodianship of the models for future development and maintenance. The models were initially developed by Neptune and Company (N&C).

Performance Assessment/Composite Analysis Modeling to Support a Holistic Strategy for the Closure of F Area, a Large Nuclear Complex at the Savannah River Site

International Nuclear Information System (INIS)

COOK, JAMES

2004-01-01

A performance-based approach is being used at the Savannah River Site to close the F area Complex. F Area consists of a number of large industrial facilities including plutonium separations, uranium fuel fabrication, tanks for storing high level waste and a number of smaller operations. A major part of the overall closure strategy is the use of techniques derived from the Performance Assessment and Composite Analysis requirements for low level waste disposal at DOE sites. This process will provide a means of demonstrating the basis for deactivation, decommissioning and closure decisions to management, stakeholders and regulators

Environmental assessment, Richton Dome site, Mississippi (US)

Energy Technology Data Exchange (ETDEWEB)

none,

1986-05-01

The Nuclear Waste Policy Act of 1982 (42 USC Sections 10101-10226) requires the environmental assessment of a potential site to include a statement of the basis for the nomination of a site as suitable for characterization. Volume 2 of this environmental assessment provides a detailed evaluation of the Richton Dome Site and its suitability as the site for a radioactive waste disposal facility under DOE siting guidelines, as well as a comparison of the Richton Dome site with other proposed sites. Evaluation of the Richton Dome site is based on the reference repository design, but the evaluation will not change if based on the Mission Plan repository concept. The comparative evaluation of proposed sites is required under DOE guidelines, but is not intended to directly support the subsequent recommendation of three sites for characterization as candidate sites. 428 refs., 24 figs., 62 tabs. (MHB)

Engineering assessment of radioactive sands and residues, Lowman Site, Lowman, Idaho

International Nuclear Information System (INIS)

1981-09-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Lowman site in order to revise the December 1977 engineering assessment of the problems resulting from the existence of radioactive sands and residues at Lowman, Idaho. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of radioactive sands and residues and radiation exposure of individuals and nearby populations, and investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 191,000 tons of radioactive sands, residues, and contaminated soils at the Lowman site constitutes the most significant environmental impact, although windblown radioactive sands and external gamma radiation also are factors

THE PENA BLANCA NATURAL ANALOGUE PERFORMANCE ASSESSMENT MODEL

Energy Technology Data Exchange (ETDEWEB)

G. Saulnier and W. Statham

2006-04-16

The Nopal I uranium mine in the Sierra Pena Blanca, Chihuahua, Mexico serves as a natural analogue to the Yucca Mountain repository. The Pena Blanca Natural Analogue Performance Assessment Model simulates the mobilization and transport of radionuclides that are released from the mine and transported to the saturated zone. The Pena Blanca Natural Analogue Performance Assessment Model uses probabilistic simulations of hydrogeologic processes that are analogous to the processes that occur at the Yucca Mountain site. The Nopal I uranium deposit lies in fractured, welded, and altered rhyolitic ash-flow tuffs that overlie carbonate rocks, a setting analogous to the geologic formations at the Yucca Mountain site. The Nopal I mine site has the following analogous characteristics as compared to the Yucca Mountain repository site: (1) Analogous source--UO{sub 2} uranium ore deposit = spent nuclear fuel in the repository; (2) Analogous geology--(i.e. fractured, welded, and altered rhyolitic ash-flow tuffs); (3) Analogous climate--Semiarid to arid; (4) Analogous setting--Volcanic tuffs overlie carbonate rocks; and (5) Analogous geochemistry--Oxidizing conditions Analogous hydrogeology: The ore deposit lies in the unsaturated zone above the water table.

THE PENA BLANCA NATURAL ANALOGUE PERFORMANCE ASSESSMENT MODEL

International Nuclear Information System (INIS)

G. Saulnier; W. Statham

2006-01-01

The Nopal I uranium mine in the Sierra Pena Blanca, Chihuahua, Mexico serves as a natural analogue to the Yucca Mountain repository. The Pena Blanca Natural Analogue Performance Assessment Model simulates the mobilization and transport of radionuclides that are released from the mine and transported to the saturated zone. The Pena Blanca Natural Analogue Performance Assessment Model uses probabilistic simulations of hydrogeologic processes that are analogous to the processes that occur at the Yucca Mountain site. The Nopal I uranium deposit lies in fractured, welded, and altered rhyolitic ash-flow tuffs that overlie carbonate rocks, a setting analogous to the geologic formations at the Yucca Mountain site. The Nopal I mine site has the following analogous characteristics as compared to the Yucca Mountain repository site: (1) Analogous source--UO 2 uranium ore deposit = spent nuclear fuel in the repository; (2) Analogous geology--(i.e. fractured, welded, and altered rhyolitic ash-flow tuffs); (3) Analogous climate--Semiarid to arid; (4) Analogous setting--Volcanic tuffs overlie carbonate rocks; and (5) Analogous geochemistry--Oxidizing conditions Analogous hydrogeology: The ore deposit lies in the unsaturated zone above the water table

Assessing the representativeness of wind data for wind turbine site evaluation

Science.gov (United States)

Renne, D. S.; Corotis, R. B.

1982-01-01

Once potential wind turbine sites (either for single installations or clusters) are identified through siting procedures, actual evaluation of the sites must commence. This evaluation is needed to obtain estimates of wind turbine performance and to identify hazards to the machine from the turbulence component of the atmosphere. These estimates allow for more detailed project planning and for preliminary financing arrangements to be secured. The site evaluation process can occur in two stages: (1) utilizing existing nearby data, and (2) establishing and monitoring an onsite measurement program. Since step (2) requires a period of at least 1 yr or more from the time a potential site has been identified, step (1) is often an essential stage in the preliminary evaluation process. Both the methods that have been developed and the unknowns that still exist in assessing the representativeness of available data to a nearby wind turbine site are discussed. How the assessment of the representativeness of available data can be used to develop a more effective onsite meteorological measurement program is also discussed.

Radiological risk assessment of a radioactively contaminated site

International Nuclear Information System (INIS)

Devgun, J.S.

1990-01-01

A limited-scope preliminary assessment of radiological risk has been conducted at a radioactively contaminated site under current site use conditions and based on the available preliminary radiological characterization data for the site. The assessment provides useful input to the remedial action planning for the site. 8 refs., 1 fig., 2 tabs

Department of Energy Plutonium ES ampersand H Vulnerability Assessment Savannah River Site interim compensatory measures

International Nuclear Information System (INIS)

Bickford, W.E.

1994-01-01

The Savannah River Site (SRS) has recently completed a self-assessment of potential vulnerabilities associated with plutonium and other transuranic materials stored at the site. An independent Working Group Assessment Team (WGAT) appointed by DOE/ES ampersand H also performed an independent assessment, and reviewed and validated the site self-assessment. The purpose of this report is to provide a status of interim compensatory measures at SRS to address hazards in advance of any corrective actions. ES ampersand H has requested this status for all vulnerabilities ranked medium or higher with respect to potential consequences to workers, environment, and the public

Technology assessment guide for application of engineered sorbent barriers to low-level radioactive waste disposal sites

Energy Technology Data Exchange (ETDEWEB)

Freeman, H.D.; Jones, E.O.; Depner, J.P.

1989-06-01

An engineered sorbent barrier (ESB) uses sorbent materials (such as activated carbon or natural zeolites) to restrict migration of radionuclides from low-level waste sites. The permeability of the ESB allows moisture to pass while the sorbent material traps or absorbs contaminants. In contrast, waste sites with impermeable barriers could fill with water, especially those waste sites in humid climates. A sorbent barrier can be a simple, effective, and inexpensive method for restricting radionuclide migration. This report provides information and references to be used in assessing the sorbent barrier technology for low-level waste disposal. The ESB assessment is based on sorbent material and soil properties, site conditions, and waste properties and inventories. These data are used to estimate the thickness of the barrier needed to meet all performance requirements for the waste site. This document addresses the following areas: (1) site information required to assess the need and overall performance of a sorbent barrier; (2) selection and testing of sorbent materials and underlying soils; (3) use of radionuclide transport models to estimate the required barrier thickness and long-term performance under a variety of site conditions; (4) general considerations for construction and quality assurance; and (5) cost estimates for applying the barrier. 37 refs., 6 figs., 2 tabs.

Safety assessment input for site selection - the Swedish example - 59031

International Nuclear Information System (INIS)

Andersson, Johan

2012-01-01

Svensk Kaernbraenslehantering AB (SKB) has performed comprehensive investigations of two candidate sites for a final repository for Sweden's spent nuclear fuel. In March 2011 SKB decided to submit licence applications for a final repository at Forsmark. Before selection, SKB stated that the site that offers the best prospects for achieving long-term safety in practice would be selected. Based on experiences previous safety assessments, a number of issues related to long-term safety need to be considered in the context of site comparison. The factors include sensitivity to climate change such as periods of permafrost and glaciations, rock mechanics evolution including the potential for thermally induced spalling and sensitivity to potential future earthquakes, current and future groundwater flow, evolution of groundwater composition and proximity to mineral resources. Each of these factors related to long-term safety for the two candidate sites is assessed in a comparative analysis of site characteristics. The assessment also considers differences in biosphere conditions and in the confidence of the site descriptions. The comparison is concluded by an assessment on how the identified differences would affect the estimated radiological risk from a repository located at either of the sites. The assessment concludes that there are a number of safety related site characteristics for which the analyses do not show any decisive differences in terms of implications on safety, between the sites Forsmark and Laxemar. However, the frequency of water conducting fractures at repository depth is much smaller at Forsmark than at Laxemar. This difference, in turn, affects the future stability of the current favourable groundwater composition, which combined with the much higher flows at Laxemar would, for the current repository design, lead to a breach in the safety functions for the buffer and the canister for many more deposition positions at Laxemar than at Forsmark. Thereby

Linkage between site characterization program and performance and design data needs

International Nuclear Information System (INIS)

Blanchard, M.B.; Dobson, D.C.; Younker, J.L.; Voegele, M.D.

1990-01-01

The basis for identifying site-specific data needs for the Yucca Mountain site was a thorough review and evaluation of the regulatory requirements for a geologic repository. The US Nuclear Regulatory Commission's (NRC) regulation governing disposal of high-level waste in a geologic repository utilizes a multiple barrier approach that includes reliance on both engineered and natural elements. Given an understanding of the regulatory requirements, the next step was to identify the natural features of the site and the components of the engineered barriers considered most likely to make significant contributions to isolation of waste at Yucca Mountain. The intent was to develop a site testing program that focused on understanding those natural site characteristics and processes most likely to contribute to waste isolation; and providing site data necessary to design and assess the performance of engineered barriers. 3 refs., 3 figs

Integrated fate and toxicity assessment for site contaminants

International Nuclear Information System (INIS)

MacDonell, Margaret; Peterson, John; Finster, Molly; Douglas, R.

2007-01-01

Understanding the fate and toxicity of environmental contaminants is essential to framing practical management decisions. Forms and bioavailable concentrations often change over time due to natural physical, chemical, and biological processes. For some sites, hundreds of contaminants may be of initial interest, and even small projects can involve a substantial number of contaminants. With multiple assessments common, attention to effectiveness and efficiency is important, and integrating fate and toxicity information provides a valuable way to focus the analyses. Fate assessments help identify what forms may be present where and when, while toxicity information indicates what health effects could result if people were exposed. The integration process is illustrated by an application for the Hanford site, to support long-term management decisions for the cesium and strontium capsules. Fate data, health-based benchmarks, and related toxicity information were effectively combined to indicate performance targets for chemicals and radionuclides identified for capsule leachate that could migrate to groundwater. More than 50 relevant benchmarks and toxicity context were identified for 15 of the 17 study contaminants; values for chronic drinking water exposure provided the common basis for selected indicators. For two chemicals, toxicity information was identified from the scientific literature to guide the performance targets. (authors)

Architecting Web Sites for High Performance

Directory of Open Access Journals (Sweden)

Arun Iyengar

2002-01-01

Full Text Available Web site applications are some of the most challenging high-performance applications currently being developed and deployed. The challenges emerge from the specific combination of high variability in workload characteristics and of high performance demands regarding the service level, scalability, availability, and costs. In recent years, a large body of research has addressed the Web site application domain, and a host of innovative software and hardware solutions have been proposed and deployed. This paper is an overview of recent solutions concerning the architectures and the software infrastructures used in building Web site applications. The presentation emphasizes three of the main functions in a complex Web site: the processing of client requests, the control of service levels, and the interaction with remote network caches.

Preliminary Performance Assessment for the Waste Management Area C at the Hanford Site in Southeast Washington

International Nuclear Information System (INIS)

Bergeron, Marcel P.; Singleton, Kristin M.; Eberlein, Susan J.

2015-01-01

A performance assessment (PA) of Single-Shell Tank (SST) Waste Management Area C (WMA C) located at the U.S. Department of Energy's (DOE) Hanford Site in southeastern Washington is being conducted to satisfy the requirements of the Hanford Federal Facility Agreement and Consent Order (HFFACO), as well as other Federal requirements and State-approved closure plans and permits. The WMP C PA assesses the fate, transport, and impacts of radionuclides and hazardous chemicals within residual wastes left in tanks and ancillary equipment and facilities in their assumed closed configuration and the subsequent risks to humans into the far future. The part of the PA focused on radiological impacts is being developed to meet the requirements for a closure authorization under DOE Order 435.1 that includes a waste incidental to reprocessing determination for residual wastes remaining in tanks, ancillary equipment, and facilities. An additional part of the PA will evaluate human health and environmental impacts from hazardous chemical inventories in residual wastes remaining in WMA C tanks, ancillary equipment, and facilities needed to meet the requirements for permitted closure under RCRA.

Preliminary Performance Assessment for the Waste Management Area C at the Hanford Site in Southeast Washington

Energy Technology Data Exchange (ETDEWEB)

Bergeron, Marcel P. [Washington River Protection Solutions LLC, Richland, WA (United States); Singleton, Kristin M. [Washington River Protection Solutions LLC, Richland, WA (United States); Eberlein, Susan J. [Washington River Protection Solutions LLC, Richland, WA (United States)

2015-01-07

A performance assessment (PA) of Single-Shell Tank (SST) Waste Management Area C (WMA C) located at the U.S. Department of Energy's (DOE) Hanford Site in southeastern Washington is being conducted to satisfy the requirements of the Hanford Federal Facility Agreement and Consent Order (HFFACO), as well as other Federal requirements and State-approved closure plans and permits. The WMP C PA assesses the fate, transport, and impacts of radionuclides and hazardous chemicals within residual wastes left in tanks and ancillary equipment and facilities in their assumed closed configuration and the subsequent risks to humans into the far future. The part of the PA focused on radiological impacts is being developed to meet the requirements for a closure authorization under DOE Order 435.1 that includes a waste incidental to reprocessing determination for residual wastes remaining in tanks, ancillary equipment, and facilities. An additional part of the PA will evaluate human health and environmental impacts from hazardous chemical inventories in residual wastes remaining in WMA C tanks, ancillary equipment, and facilities needed to meet the requirements for permitted closure under RCRA.

Performance assessment methods for mixed waste sites at the Savannah River Plant

International Nuclear Information System (INIS)

King, C.M.; Marter, W.L.; Looney, B.B.

1987-01-01

Risk assessment techniques were applied to Savannah River Plant (SRP) waste facilities as part of a program on waste site cleanup and groundwater protection. The components of risk assessment and the technical basis for application of the risk evaluation process to the principal pollutants at SRP (radionuclides, toxic chemicals, and carcinogenic compounds) are given. An extensive technical data base from the fields of radiation health physics, toxicology, and environmental sciences is required. Data are summarized for each class of contaminant and parameter values are provided for use in numerical analysis of risk. A review of risk assessment uncertainties and the limitations of predictive risk assessment are summarized. Risk estimators for each class of contaminants at the SRP were tabulated for radionuclides, toxic chemicals, and carcinogens from the technical literature. Estimation of human health risk is not an additive process for radiation effects and chemical carcinogensis since their respective dosimetric models are distinctly different - even though the induction of cancer is reported to be the common end result. Risk estimation for radionuclides and chemical carcinogens should be tabulated separately. Impacts due to toxic chemicals in the biosphere should also be estimated as a separate entity because toxic chemical risk estimators are uniquely different and do not reflect the probability of a detrimental health effect. 29 refs., 3 figs., 2 tabs

Performance Assessment Position Paper: Time for Compliance

International Nuclear Information System (INIS)

Wilhite, E.L.

2003-01-01

This study lays out the historical development of the time frame for a low-level waste disposal facility to demonstrate compliance with the DOE performance objectives and requirements. The study recommends that 1,000 years should be used as the time for compliance for all of the performance objectives and requirements (i.e., for the all-pathways, air pathway, radon emanation, water resource protection and inadvertent intruder analyses) for all low-level waste disposal facility performance assessments at the Savannah River Site

Independent University Study to Assess the Performance of a Humate Amendment for Copper Detoxification at the H-12 Outfall at Savannah River Site

Energy Technology Data Exchange (ETDEWEB)

Looney, B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Harmon, S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); King, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-09-06

The overarching objective of this study was to evaluate the effectiveness of the copper detoxification process that is in place at the Savannah River Site H-12 Outfall. The testing was performed in two phases; Phase 1 assessed the safety and potential for intrinsic toxicity of the humate amendment being used at the H-12 Outfall, Borregro HA-1, as well as an alternative amendment sodium humic acid. The second phase assessed the effectiveness of Borregro HA-1 in mitigating and reducing toxic effects of copper.

Assessing hypotheses about nesting site occupancy dynamics

Science.gov (United States)

Bled, Florent; Royle, J. Andrew; Cam, Emmanuelle

2011-01-01

Hypotheses about habitat selection developed in the evolutionary ecology framework assume that individuals, under some conditions, select breeding habitat based on expected fitness in different habitat. The relationship between habitat quality and fitness may be reflected by breeding success of individuals, which may in turn be used to assess habitat quality. Habitat quality may also be assessed via local density: if high-quality sites are preferentially used, high density may reflect high-quality habitat. Here we assessed whether site occupancy dynamics vary with site surrogates for habitat quality. We modeled nest site use probability in a seabird subcolony (the Black-legged Kittiwake, Rissa tridactyla) over a 20-year period. We estimated site persistence (an occupied site remains occupied from time t to t + 1) and colonization through two subprocesses: first colonization (site creation at the timescale of the study) and recolonization (a site is colonized again after being deserted). Our model explicitly incorporated site-specific and neighboring breeding success and conspecific density in the neighborhood. Our results provided evidence that reproductively "successful'' sites have a higher persistence probability than "unsuccessful'' ones. Analyses of site fidelity in marked birds and of survival probability showed that high site persistence predominantly reflects site fidelity, not immediate colonization by new owners after emigration or death of previous owners. There is a negative quadratic relationship between local density and persistence probability. First colonization probability decreases with density, whereas recolonization probability is constant. This highlights the importance of distinguishing initial colonization and recolonization to understand site occupancy. All dynamics varied positively with neighboring breeding success. We found evidence of a positive interaction between site-specific and neighboring breeding success. We addressed local

Quality assurance in performance assessments

Energy Technology Data Exchange (ETDEWEB)

Maul, P.R.; Watkins, B.M.; Salter, P.; Mcleod, R [QuantiSci Ltd, Henley-on-Thames (United Kingdom)

1999-01-01

Following publication of the Site-94 report, SKI wishes to review how Quality Assurance (QA) issues could be treated in future work both in undertaking their own Performance Assessment (PA) calculations and in scrutinising documents supplied by SKB (on planning a repository for spent fuels in Sweden). The aim of this report is to identify the key QA issues and to outline the nature and content of a QA plan which would be suitable for SKI, bearing in mind the requirements and recommendations of relevant standards. Emphasis is on issues which are specific to Performance Assessments for deep repositories for radioactive wastes, but consideration is also given to issues which need to be addressed in all large projects. Given the long time over which the performance of a deep repository system must be evaluated, the demonstration that a repository is likely to perform satisfactorily relies on the use of computer-generated model predictions of system performance. This raises particular QA issues which are generally not encountered in other technical areas (for instance, power station operations). The traceability of the arguments used is a key QA issue, as are conceptual model uncertainty, and code verification and validation; these were all included in the consideration of overall uncertainties in the Site-94 project. Additionally, issues which are particularly relevant to SKI include: How QA in a PA fits in with the general QA procedures of the organisation undertaking the work. The relationship between QA as applied by the regulator and the implementor of a repository development programme. Section 2 introduces the discussion of these issues by reviewing the standards and guidance which are available from national and international organisations. This is followed in Section 3 by a review of specific issues which arise from the Site-94 exercise. An outline procedure for managing QA issues in SKI is put forward as a basis for discussion in Section 4. It is hoped that

Quality assurance in performance assessments

International Nuclear Information System (INIS)

Maul, P.R.; Watkins, B.M.; Salter, P.; Mcleod, R

1999-01-01

Following publication of the Site-94 report, SKI wishes to review how Quality Assurance (QA) issues could be treated in future work both in undertaking their own Performance Assessment (PA) calculations and in scrutinising documents supplied by SKB (on planning a repository for spent fuels in Sweden). The aim of this report is to identify the key QA issues and to outline the nature and content of a QA plan which would be suitable for SKI, bearing in mind the requirements and recommendations of relevant standards. Emphasis is on issues which are specific to Performance Assessments for deep repositories for radioactive wastes, but consideration is also given to issues which need to be addressed in all large projects. Given the long time over which the performance of a deep repository system must be evaluated, the demonstration that a repository is likely to perform satisfactorily relies on the use of computer-generated model predictions of system performance. This raises particular QA issues which are generally not encountered in other technical areas (for instance, power station operations). The traceability of the arguments used is a key QA issue, as are conceptual model uncertainty, and code verification and validation; these were all included in the consideration of overall uncertainties in the Site-94 project. Additionally, issues which are particularly relevant to SKI include: How QA in a PA fits in with the general QA procedures of the organisation undertaking the work. The relationship between QA as applied by the regulator and the implementor of a repository development programme. Section 2 introduces the discussion of these issues by reviewing the standards and guidance which are available from national and international organisations. This is followed in Section 3 by a review of specific issues which arise from the Site-94 exercise. An outline procedure for managing QA issues in SKI is put forward as a basis for discussion in Section 4. It is hoped that

Visualization of Safety Assessment Result Using GIS in SITES

International Nuclear Information System (INIS)

Yun, Bong-Yo; Park, Joo Wan; Park, Se-Moon; Kim, Chang-Lak

2006-01-01

Site Information and Total Environmental database management System (SITES) is an integrated program for overall data analysis, environmental monitoring, and safety analysis that are produced from the site investigation and environmental assessment of the relevant nuclear facility. SITES is composed of three main modules such as Site Environment Characterization database for Unified and Reliable Evaluation system (SECURE), Safety Assessment INTegration system (SAINT) and Site Useful Data Analysis and ALarm system (SUDAL). The visualization function of safety assessment and environmental monitoring results is designed. This paper is to introduce the visualization design method using Geographic Information System (GIS) for SITES

Baseline risk assessment of groundwater contamination at the Uranium Mill Tailings Site near Gunnison, Colorado

Energy Technology Data Exchange (ETDEWEB)

1993-12-01

This Baseline Risk Assessment of Groundwater Contamination at the Uranium Mill Tailings Site Near Gunnison, Colorado evaluates potential impacts to public health or the environment resulting from groundwater contamination at the former uranium mill processing site. The tailings and other contaminated material at this site are being placed in an off-site disposal cell by the US Department of Energy`s (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating groundwater contamination. This is the second risk assessment of groundwater contamination at this site. The first risk assessment was performed primarily to evaluate existing domestic wells. This risk assessment evaluates the most contaminated monitor wells at the processing site. It will be used to assist in determining what remedial action is needed for contaminated groundwater at the site after the tailings are relocated. This risk assessment follows an approach outlined by the US Environmental Protection Agency (EPA). The first step is to evaluate groundwater data collected from monitor wells at the site. Evaluation of these data showed that the main contaminants in the groundwater are cadmium, cobalt, iron, manganese, sulfate, uranium, and some of the products of radioactive decay of uranium.

Baseline risk assessment of groundwater contamination at the Uranium Mill Tailings Site near Gunnison, Colorado

International Nuclear Information System (INIS)

1993-12-01

This Baseline Risk Assessment of Groundwater Contamination at the Uranium Mill Tailings Site Near Gunnison, Colorado evaluates potential impacts to public health or the environment resulting from groundwater contamination at the former uranium mill processing site. The tailings and other contaminated material at this site are being placed in an off-site disposal cell by the US Department of Energy's (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating groundwater contamination. This is the second risk assessment of groundwater contamination at this site. The first risk assessment was performed primarily to evaluate existing domestic wells. This risk assessment evaluates the most contaminated monitor wells at the processing site. It will be used to assist in determining what remedial action is needed for contaminated groundwater at the site after the tailings are relocated. This risk assessment follows an approach outlined by the US Environmental Protection Agency (EPA). The first step is to evaluate groundwater data collected from monitor wells at the site. Evaluation of these data showed that the main contaminants in the groundwater are cadmium, cobalt, iron, manganese, sulfate, uranium, and some of the products of radioactive decay of uranium

Radiological performance assessment for the E-Area Vaults Disposal Facility

International Nuclear Information System (INIS)

Cook, J.R.

1994-01-01

These document contains appendices A-M for the performance assessment. They are A: details of models and assumptions, B: computer codes, C: data tabulation, D: geochemical interactions, E: hydrogeology of the Savannah River Site, F: software QA plans, G: completeness review guide, H: performance assessment peer review panel recommendations, I: suspect soil performance analysis, J: sensitivity/uncertainty analysis, K: vault degradation study, L: description of naval reactor waste disposal, M: porflow input file

DOE site-specific threat assessment

International Nuclear Information System (INIS)

West, D.J.; Al-Ayat, R.A.; Judd, B.R.

1985-01-01

A facility manager faced with the challenges of protecting a nuclear facility against potential threats must consider the likelihood and consequences of such threats, know the capabilities of the facility safeguards and security systems, and make informed decisions about the cost-effectivness of safeguards and security upgrades. To help meet these challenges, the San Francisco Operations Office of the Department of Energy, in conjunction with the Lawrence Livermore Laboratory, has developed a site-specific threat assessment approach and a quantitative model to improve the quality and consistency of site-specific threat assessment and resultant security upgrade decisions at sensitive Department of Energy facilities. 5 figs

Tiger Team Assessment of the Savannah River Site

International Nuclear Information System (INIS)

1990-06-01

This draft document contains findings identified during the Tiger Team Compliance Assessment of the US Department of Energy Savannah River Site (SRS), located in three counties (Aiken, Barnwell and Allendale), South Carolina. The Assessment was directed by the Department's Office of the Assistant Secretary for Environment, Safety, and Health (ES ampersand H) and was conducted from January 29 to March 23, 1990. The Savannah River Site Tiger Team Compliance Assessment was broad in scope covering the Environment, Safety and Health, and Management areas and was designed to determine the site's compliance with applicable Federal (including DOE), state, and local regulations and requirements. The scope of the Environmental assessment was sitewide while the Safety and Health assessments included site operating facilities (except reactors), and the sitewide elements of Aviation Safety, Emergency Preparedness, Medical Services, and Packaging and Transportation

Lessons learned: Needs for improving human health risk assessment at USDOE Sites

International Nuclear Information System (INIS)

Hamilton, L.D.; Holtzman, S.; Meinhold, A.F.; Morris, S.C.; Rowe, M.D.; Daniels, J.I.; Layton, D.W.; Anspaugh, L.R.

1993-09-01

Realistic health risk assessments were performed in a pilot study of three U.S. Department of Energy (USDOE) sites. These assessments, covering a broad spectrum of data and methods, were used to identify needs for improving future health risk assessments at USDOE sites. Topics receiving specific recommendations for additional research include: choice of distributions for Monte Carlo simulation; estimation of risk reduction; analysis of the U.S. Department of Agriculture Database on food and nutrient intakes; investigations on effects of food processing on contaminant levels; background food and environmental concentrations of contaminants; method for handling exposures to groundwater plumes, methods for analyzing less than lifetime exposure to carcinogens; and improvement of bioaccumulation factors

Optimising the remediation of sites contaminated by the Wismut uranium mining operations using performance and risk assessment

Energy Technology Data Exchange (ETDEWEB)

Pelz, F.; Jakubick, A.Th.; Kahnt, R. [Wismut GmbH, Chemnitz (Germany)

2003-07-01

The cost and risk assessment at Wismut GmbH is performed for optimising the remediation of sites contaminated by uranium mining and milling. An iterative either probabilistic or deterministic 'top-down' model of the remediation project as an integrated system is used. Initially all relevant processes are captured in a rather abstract and simplistic way. In the course of the model development those variables and processes to which results have been shown to be sensitive are described in more detail. This approach is useful for identifying any gaps in the knowledge base that have to be filled in the course of the multi-attributive decision making. The requirement for optimisation, also with respect to socio-economic impacts, is met by including other variables in addition to costs and health risks. (authors)

Optimising the remediation of sites contaminated by the Wismut uranium mining operations using performance and risk assessment

International Nuclear Information System (INIS)

Pelz, F.; Jakubick, A.Th.; Kahnt, R.

2003-01-01

The cost and risk assessment at Wismut GmbH is performed for optimising the remediation of sites contaminated by uranium mining and milling. An iterative either probabilistic or deterministic 'top-down' model of the remediation project as an integrated system is used. Initially all relevant processes are captured in a rather abstract and simplistic way. In the course of the model development those variables and processes to which results have been shown to be sensitive are described in more detail. This approach is useful for identifying any gaps in the knowledge base that have to be filled in the course of the multi-attributive decision making. The requirement for optimisation, also with respect to socio-economic impacts, is met by including other variables in addition to costs and health risks. (authors)

Total system performance assessment - 1995: An evaluation of the potential Yucca Mountain Repository

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-11-01

The U.S. Department of Energy (DOE) is currently investigating the feasibility of permanently disposing the nation`s commercial high-level radioactive wastes (in the form of spent fuel from the over 100 electric power-generating nuclear reactors across the U.S.) and a portion of the defense high-level radioactive wastes (currently stored at federal facilities around the country) in the unsaturated tuffaceous rocks at Yucca Mountain, Nevada. Quantitative predictions based on the most current understanding of the processes and parameters potentially affecting the long-term behavior of the disposal system are used to assess the ability of the site and its associated engineered designs to meet regulatory objectives set forward by the U.S. Nuclear Regulatory Commission (NRC) and the U.S. Environmental Protection Agency (EPA). The evaluation of the ability of the overall system to meet the performance objectives specified in the applicable regulatory standards has been termed total system performance assessment (TSPA). The aim of any total system performance assessment is to be as complete and reasonably conservative as possible and to assure that the descriptions of the predictive models and parameters are sufficient to ascertain their accuracy. Total system performance assessments evolve with time. As additional site and design information is generated, performance assessment analyses can be revised to become more representative of the expected conditions and remove some of the conservative assumptions necessitated by the incompleteness of site and design data. Previous iterations of total system performance assessment of the Yucca Mountain site and associated engineered barriers have been conducted in 1991 and 1993. These analyses have been documented in Barnard, Eslinger, Wilson and Andrews.

Total system performance assessment - 1995: An evaluation of the potential Yucca Mountain Repository

International Nuclear Information System (INIS)

1995-11-01

The U.S. Department of Energy (DOE) is currently investigating the feasibility of permanently disposing the nation's commercial high-level radioactive wastes (in the form of spent fuel from the over 100 electric power-generating nuclear reactors across the U.S.) and a portion of the defense high-level radioactive wastes (currently stored at federal facilities around the country) in the unsaturated tuffaceous rocks at Yucca Mountain, Nevada. Quantitative predictions based on the most current understanding of the processes and parameters potentially affecting the long-term behavior of the disposal system are used to assess the ability of the site and its associated engineered designs to meet regulatory objectives set forward by the U.S. Nuclear Regulatory Commission (NRC) and the U.S. Environmental Protection Agency (EPA). The evaluation of the ability of the overall system to meet the performance objectives specified in the applicable regulatory standards has been termed total system performance assessment (TSPA). The aim of any total system performance assessment is to be as complete and reasonably conservative as possible and to assure that the descriptions of the predictive models and parameters are sufficient to ascertain their accuracy. Total system performance assessments evolve with time. As additional site and design information is generated, performance assessment analyses can be revised to become more representative of the expected conditions and remove some of the conservative assumptions necessitated by the incompleteness of site and design data. Previous iterations of total system performance assessment of the Yucca Mountain site and associated engineered barriers have been conducted in 1991 and 1993. These analyses have been documented in Barnard, Eslinger, Wilson and Andrews

Site characterization in fractured crystalline rock

International Nuclear Information System (INIS)

Andersson, Peter; Andersson, J.E.; Gustafsson, E.; Nordqvist, R.; Voss, C.

1993-03-01

This report concerns a study which is part of the SKI performance assessment project SITE-94. SITE-94 is a performance assessment of a hypothetical repository at a real site. The main objective of the project is to determine how site specific data should be assimilated into the performance assessment process and to evaluate how uncertainties inherent in site characterization will influence performance assessment results. Other important elements of SITE-94 are the development of a practical and defensible methodology for defining, constructing and analyzing scenarios, the development of approaches for treatment of uncertainties, evaluation of canister integrity, and the development and application of an appropriate Quality Assurance plan for Performance Assessments. (111 refs.)

The Moulded Site Data (MSD) wind correlation method: description and assessment

Energy Technology Data Exchange (ETDEWEB)

King, C.; Hurley, B.

2004-12-01

The long-term wind resource at a potential windfarm site may be estimated by correlating short-term on-site wind measurements with data from a regional meteorological station. A correlation method developed at Airtricity is described in sufficient detail to be reproduced. An assessment of its performance is also described; the results may serve as a guide to expected accuracy when using the method as part of an annual electricity production estimate for a proposed windfarm. (Author)

A formalism to generate probability distributions for performance-assessment modeling

International Nuclear Information System (INIS)

Kaplan, P.G.

1990-01-01

A formalism is presented for generating probability distributions of parameters used in performance-assessment modeling. The formalism is used when data are either sparse or nonexistent. The appropriate distribution is a function of the known or estimated constraints and is chosen to maximize a quantity known as Shannon's informational entropy. The formalism is applied to a parameter used in performance-assessment modeling. The functional form of the model that defines the parameter, data from the actual field site, and natural analog data are analyzed to estimate the constraints. A beta probability distribution of the example parameter is generated after finding four constraints. As an example of how the formalism is applied to the site characterization studies of Yucca Mountain, the distribution is generated for an input parameter in a performance-assessment model currently used to estimate compliance with disposal of high-level radioactive waste in geologic repositories, 10 CFR 60.113(a)(2), commonly known as the ground water travel time criterion. 8 refs., 2 figs

Evaluation of the OnSite malaria rapid test performance in Miandrivazo, Madagascar.

Science.gov (United States)

Ravaoarisoa, E; Andriamiandranoro, T; Raherinjafy, R; Jahevitra, M; Razanatsiorimalala, S; Andrianaranjaka, V; Randrianarivelojosia, M

2017-10-01

The performance of the malaria rapid diagnostic test OnSite-for detecting pan specific pLDH and Plasmodium falciparum specific HRP2 - was assessed during the malaria transmission peak period in Miandrivazo, in the southwestern part of Madagascar from April 20 to May 6, 2010. At the laboratory, the quality control OnSite Malaria Rapid Test according to the WHO/TDR/FIND method demonstrated that the test had good sensitivity. Of the 218 OnSite tests performed at the Miandrivazo Primary Health Center on patients with fever or a recent history of fever, four (1.8%, 95% CI: 0.6-4.9%) were invalid. Ninety four (43,1%) cases of malaria were confirmed by microscopy, of which 90 were P. falciparum malaria and 4 Plasmodium vivax malaria. With a Cohen's kappa coefficient of 0.94, the agreement between microscopy and OnSite is excellent. Compared with the rapid test CareStart™ commonly used within the public health structures in Madagascar, the sensitivity and specificity of the OnSite test were 97.9% and 96.8%.

Challenges in radiological impact assessment studies at new sites for nuclear facilities and its safety review and assessment for siting consent

International Nuclear Information System (INIS)

Mukherjee Roy, Susmita; Roshan, A.D.; Bishnoi, L.R.

2018-01-01

One of the basic requirement of site evaluation for a Nuclear Facility (NF) is radiological impact assessment (RIA). This involves evaluation of transportation of radioactive materials discharged from a nuclear facility under normal operational or accidental conditions, through different compartments of environment viz. air, land and water, and finally assessment of its consequences. Amongst others, site characteristics and the site related parameters play major role in evaluation of impact of postulated releases from NPPs. Doses to public from both external and internal exposures are computed to assess potential consequences of a radiological release and acceptability of the site-plant pair is established based on the outcome of this assessment. A comprehensive study of the site characteristics including meteorology, hydrology, hydro-geology and demography of the region along with details of land and water use, bioaccumulation, transfer to and from the environmental matrices is required for accomplishing satisfactory RIA

Uncertainty management in radioactive waste repository site assessment

International Nuclear Information System (INIS)

Baldwin, J.f.; Martin, T.P.; Tocatlidou

1994-01-01

The problem of performance assessment of a site to serve as a repository for the final disposal of radioactive waste involves different types of uncertainties. Their main sources include the large temporal and spatial considerations over which safety of the system has to be ensured, our inability to completely understand and describe a very complex structure such as the repository system, lack of precision in the measured information etc. These issues underlie most of the problems faced when rigid probabilistic approaches are used. Nevertheless a framework is needed, that would allow for an optimal aggregation of the available knowledge and an efficient management of the various types of uncertainty involved. In this work a knowledge-based modelling of the repository selection process is proposed that through a consequence analysis, evaluates the potential impact that hypothetical scenarios will have on a candidate site. The model is organised around a hierarchical structure, relating the scenarios with the possible events and processes that characterise them, and the site parameters. The scheme provides for both crisp and fuzzy parameter values and uses fuzzy semantic unification and evidential support logic reference mechanisms. It is implemented using the artificial intelligence language FRIL and the interaction with the user is performed through a windows interface

Abstraction of information in repository performance assessments. Examples from the SKI project Site-94

International Nuclear Information System (INIS)

Dverstorp, B.; Andersson, J.

1995-01-01

Performance Assessment of a nuclear waste repository implies an analysis of a complex system with many interacting processes. Even if some of these processes may be known to large detail, problems arise when combining all information, and means of abstracting information from complex detailed models into models that couple different processes are needed. Clearly, one of the major objectives of performance assessment, to calculate doses or other performance indicators, implies an enormous abstraction of information compared to all information that is used as input. Other problems are that the knowledge of different parts or processes is strongly variable and adjustments, interpretations, are needed when combining models from different disciplines. In addition, people as well as computers, even today, always have a limited capacity to process information and choices have to be made. However, because abstraction of information clearly is unavoidable in performance assessment the validity of choices made, always need to be scrutinized and judgements made need to be updated in an iterative process

TURVA-2012: Performance assessment

International Nuclear Information System (INIS)

Hellae, Pirjo; Snellman, Margit; Marcos, Nuria; Pastina, Barbara; Smith, Paul; Koskinen, Kari

2014-01-01

TURVA-2012 is Posiva's safety case in support of the Preliminary Safety Analysis Report (PSAR) and application for a construction licence for a repository for disposal of spent nuclear fuel at the Olkiluoto site in south-western Finland. Posiva's safety concept is based on long-term isolation and containment, which is achieved through a robust engineered barrier system (EBS) design and favourable geological conditions at the repository site. The reference design considered in the TURVA-2012 safety case is the KBS-3V design, with the EBS consisting of a copper-iron canister, a buffer of swelling clay material, a backfill in the deposition tunnels of low-permeability material and closure of the central tunnels and other underground openings. The host rock acts as a natural barrier. Each barrier contributes to safety through one or more safety function. The conditions needed for the barriers to fulfil their respective safety functions are expressed in terms of performance targets for the EBS and the target properties for the host rock. The performance assessment (Posiva, 2013), which is a key component of TURVA-2012, analyses the ability of the repository system to provide containment and isolation of the spent nuclear fuel during the long-term evolution of the system and the site. The conditions needed for the barriers to fulfil their respective safety functions are expressed in terms of performance targets for the engineered barriers and target properties for the host rock, for example properties related to the corrosion resistance and mechanical strength of the canister as well as groundwater flow and composition. The analyses take into account the uncertainties in the initial state, the subsequent thermal, hydraulic, mechanical and chemical evolution of the repository system and uncertainties in the evolution. The conclusions of the performance assessment are based mostly on the output of key modelling activities. Whenever modelling is not possible the conclusions

Site characterization at the Rabbit Valley Geophysical Performance Evaluation Range

International Nuclear Information System (INIS)

Koppenjan, S.; Martinez, M.

1994-01-01

The United States Department of Energy (US DOE) is developing a Geophysical Performance Evaluation Range (GPER) at Rabbit Valley located 30 miles west of Grand Junction, Colorado. The purpose of the range is to provide a test area for geophysical instruments and survey procedures. Assessment of equipment accuracy and resolution is accomplished through the use of static and dynamic physical models. These models include targets with fixed configurations and targets that can be re-configured to simulate specific specifications. Initial testing (1991) combined with the current tests at the Rabbit Valley GPER will establish baseline data and will provide performance criteria for the development of geophysical technologies and techniques. The US DOE's Special Technologies Laboratory (STL) staff has conducted a Ground Penetrating Radar (GPR) survey of the site with its stepped FM-CW GPR. Additionally, STL contracted several other geophysical tests. These include an airborne GPR survey incorporating a ''chirped'' FM-CW GPR system and a magnetic survey with a surfaced-towed magnetometer array unit Ground-based and aerial video and still frame pictures were also acquired. STL compiled and analyzed all of the geophysical maps and created a site characterization database. This paper discusses the results of the multi-sensor geophysical studies performed at Rabbit Valley and the future plans for the site

Assessment of the Nevada Test Site as a Site for Distributed Resource Testing and Project Plan: March 2002

Energy Technology Data Exchange (ETDEWEB)

Horgan, S.; Iannucci, J.; Whitaker, C.; Cibulka, L.; Erdman, W.

2002-05-01

The objective of this project was to evaluate the Nevada Test Site (NTS) as a location for performing dedicated, in-depth testing of distributed resources (DR) integrated with the electric distribution system. In this large scale testing, it is desired to operate multiple DRs and loads in an actual operating environment, in a series of controlled tests to concentrate on issues of interest to the DR community. This report includes an inventory of existing facilities at NTS, an assessment of site attributes in relation to DR testing requirements, and an evaluation of the feasibility and cost of upgrades to the site that would make it a fully qualified DR testing facility.

Performance assessment development for a LILW repository in Slovenia

International Nuclear Information System (INIS)

Zeleznik, N.; Mele, I.

2001-01-01

Simultaneously with the site selection process for a low and intermediate level radioactive waste (LILW) repository, the preliminary assessment of the influence of the specific disposal concept on the environment and on the population was developed. The performance assessment team, organized in 1997 by ARAO, prepared several basic studies in order to clarify the objectives of the performance and safety assessment (PA/SA) procedure. In 1999 also the first performance assessment of two safety cases (surface and underground) for generic site for a LILW repository was realized. In the year 2000 activities on PA/SA analyses continued. A systematic, generic list was prepared of all possible features, events and processes (FEP list) predictable for surface or underground LILW disposal in Slovenia. Recommended and selected were the most reliable scenarios with conceptual models for LILW disposal in normal and altered evolution conditions. New verification of the obtained results was done with more powerful and accurate models for the surface repository over an aquifer of lower water permeability and an underground repository in a plastic rock. The results for both generic cases under normal evolution scenarios showed that there is a negligible dose influence on members of the critical population due to the migration of radionuclides from the foreseen LILW repository. The results of the already performed work as well as plans for the future activities are presented in the paper.(author)

Y-12 site-specific earthquake response analysis and soil liquefaction assessment

International Nuclear Information System (INIS)

Ahmed, S.B.; Hunt, R.J.; Manrod, W.E. III.

1995-01-01

A site-specific earthquake response analysis and soil liquefaction assessment were performed for the Oak Ridge Y-12 Plant. The main purpose of these studies was to use the results of the analyses for evaluating the safety of the performance category -1, -2, and -3 facilities against the natural phenomena seismic hazards. Earthquake response was determined for seven (7), one dimensional soil columns (Fig. 12) using two horizontal components of the PC-3 design basis 2000-year seismic event. The computer program SHAKE 91 (Ref. 7) was used to calculate the absolute response accelerations on top of ground (soil/weathered shale) and rock outcrop. The SHAKE program has been validated for horizontal response calculations at periods less than 2.0 second at several sites and consequently is widely accepted in the geotechnical earthquake engineering area for site response analysis

Hanford Site Performance Report - March 1999

International Nuclear Information System (INIS)

EDER, D.M.

2001-01-01

The purpose of the Hanford Site Performance Report is to provide the Department of Energy Richland Operations Office's (DOE-RL's) report of Hanford's performance by: U.S. Department of Energy, Richland Operations Office, Project Hanford Management Contract (PHMC) through Fluor Daniel Hanford, Inc. (FDH) and its subcontractors, Environmental Restoration Contract through Bechtel Hanford, Inc. (BHI), and its subcontractors, and Pacific Northwest National Laboratories (PNNL) for Science and Technology (S and T) Mission and support to the Environmental Management (EM). This report is published monthly with the intent of relating work performance and progress in the context of the Success Indicators and Critical Success Factors as outlined in the Hanford Strategic Plan. On a quarterly basis, the report also addresses performance and progress related to the Science and Technology Mission's Critical Outcomes as derived from the Hanford Strategic Plan. Section A of this report is the Executive Summary, encapsulating high-level data in this report into an overall brief. Summary information provided includes Notable Accomplishments, a performance profile with associated analyses, Critical Issues, Key Integration Activities, and a ''quick list'' of Upcoming Key Events. Section B of this report, the Site Summary section, provides Environmental Management performance data specifically organized to the pertinent Critical Success Factors and Success Indicators, and Science and Technology data in the context of the Critical Outcomes. The Site Summary demonstrates the various missions' overall progress against these strategic objectives. The information is presented in both narrative and graphical formats. The remaining sections provide performance data relative to each individual mission area (e.g., Waste Management, Spent Nuclear Fuels, etc.). The information provided in the Mission Area sections is at a level of greater detail than is presented in either the Executive Summary or

Hanford Site Performance Report - May 1999

International Nuclear Information System (INIS)

EDER, D.M.

2001-01-01

The purpose of the Hanford Site Performance Report is to provide the Department of Energy Richland Operations Office's (DOE-RL's) report of Hanford's performance by: U. S. Department of Energy, Richland Operations Office, Project Hanford Management Contract (PHMC) through Fluor Daniel Hanford, Inc. (FDH) and its subcontractors, Environmental Restoration Contract through Bechtel Hanford, Inc. (BHI), and its subcontractors, and Pacific Northwest National Laboratories (PNNL) for Science and Technology (S and T) Mission and support to the Environmental Management (EM). This report is published monthly with the intent of relating work performance and progress in the context of the Success Indicators and Critical Success Factors as outlined in the Hanford Strategic Plan. On a quarterly basis, the report also addresses performance and progress related to the Science and Technology Mission's Critical Outcomes as derived from the Hanford Strategic Plan. Section A of this report is the Executive Summary, encapsulating high-level data in this report into an overall brief. Summary information provided includes Notable Accomplishments, a performance profile with associated analyses, Critical Issues, Key Integration Activities, and a ''quick list'' of Upcoming Key Events. Section B of this report, the Site Summary section, provides Environmental Management performance data specifically organized to the pertinent Critical Success Factors and Success Indicators, and Science and Technology data in the context of the Critical Outcomes. The Site Summary demonstrates the various missions' overall progress against these strategic objectives. The information is presented in both narrative and graphical formats. The remaining sections provide performance data relative to each individual mission area (e.g., Waste Management, Spent Nuclear Fuels, etc.). The information provided in the Mission Area sections is at a level of greater detail than is presented in either the Executive Summary or

Hanford Site Performance Report - April 1999

International Nuclear Information System (INIS)

EDER, D.M.

2001-01-01

The purpose of the Hanford Site Performance Report is to provide the Department of Energy Richland Operations Office's (DOE-RL's) report of Hanford's performance by: U.S. Department of Energy, Richland Operations Office, Project Hanford Management Contract (PHMC) through Fluor Daniel Hanford, Inc. (FDH) and its subcontractors, Environmental Restoration Contract through Bechtel Hanford, Inc. (BHI), and its subcontractors, and Pacific Northwest National Laboratories (PNNL) for Science and Technology (S and T) Mission and support to the Environmental Management (EM). This report is published monthly with the intent of relating work performance and progress in the context of the Success Indicators and Critical Success Factors as outlined in the Hanford Strategic Plan. On a quarterly basis, the report also addresses performance and progress related to the Science and Technology Mission's Critical Outcomes as derived from the Hanford Strategic Plan. Section A of this report is the Executive Summary, encapsulating high-level data in this report into an overall brief. Summary information provided includes Notable Accomplishments, a performance profile with associated analyses, Critical Issues, Key Integration Activities, and a ''quick list'' of Upcoming Key Events. Section B of this report, the Site Summary section, provides Environmental Management performance data specifically organized to the pertinent Critical Success Factors and Success Indicators, and Science and Technology data in the context of the Critical Outcomes. The Site Summary demonstrates the various missions' overall progress against these strategic objectives. The information is presented in both narrative and graphical formats. The remaining sections provide performance data relative to each individual mission area (e.g., Waste Management, Spent Nuclear Fuels, etc.). The information provided in the Mission Area sections is at a level of greater detail than is presented in either the Executive Summary or

Hanford Site performance report - December 1998

International Nuclear Information System (INIS)

EDER, D.M.

2001-01-01

The purpose of the Hanford Site Performance Report is to provide the Department of Energy Richland Operations Office's (DOE-RL's) report of Hanford's performance by: U. S. Department of Energy, Richland Operations Office, Project Hanford Management Contract (PHMC) through Fluor Daniel Hanford, Inc. (FDH) and its subcontractors, Environmental Restoration Contract through Bechtel Hanford, Inc. (BHI), and its subcontractors, and Pacific Northwest National Laboratories (PNNL) for Science and Technology support to the Environmental Management (EM) mission. This report is published monthly with the intent of relating work performance and progress in the context of the Success Indicators and Critical Success Factors as outlined in the Hanford Strategic Plan. Currently, the report focuses on the EM mission, and will be expanded in the future to include non-EM activities. Section A of this report is the Executive Summary, encapsulating high-level data in this report into an overall brief. Summary information provided includes Notable Accomplishments, a tabular performance profile with associated analyses, Critical Issues, Key Integration Activities, a look at Significant Trends, and a ''quick list'' of Upcoming Key Events. Section B of this report, the Site Summary section, provides Environmental Management performance data specifically organized to the pertinent Critical Success Factors and Success Indicators. The Site Summary is a compilation of performance data from all of the Mission Areas and the Projects that comprise these Mission Areas; the information is presented in both narrative and graphical formats. The remaining sections provide performance data relative to each individual mission area (e.g., Waste Management, Spent Nuclear Fuels, etc.). The information provided in the Mission Area sections is at a level of greater detail than is presented in either the Executive Summary or the Site Summary sections. At the end of this report, a glossary of terms is provided

The use of performance assessments in Yucca Mountain repository waste package design activities

International Nuclear Information System (INIS)

Jardine, L.J.

1990-01-01

The Yucca Mountain Project is developing performance assessment approaches as part of the evaluations of the suitability of Yucca Mountain as a repository site. Lawrence Livermore National Laboratory is developing design concepts and the scientific performance assessment methodologies and techniques used for the waste package and engineered barrier system components. This paper presents an overview of the approach under development for postclosure performance assessments that will guide the conceptual design activities and assist in the site suitability evaluations. This approach includes establishing and modeling for the long time periods required by regulations: near-field environment characteristics surrounding the emplaced wastes; container materials performance responses; and waste form properties. All technical work is being done under a fully qualified quality assurance program

Radioactive Waste Management Complex performance assessment: Draft

Energy Technology Data Exchange (ETDEWEB)

Case, M.J.; Maheras, S.J.; McKenzie-Carter, M.A.; Sussman, M.E.; Voilleque, P.

1990-06-01

A radiological performance assessment of the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory was conducted to demonstrate compliance with appropriate radiological criteria of the US Department of Energy and the US Environmental Protection Agency for protection of the general public. The calculations involved modeling the transport of radionuclides from buried waste, to surface soil and subsurface media, and eventually to members of the general public via air, ground water, and food chain pathways. Projections of doses were made for both offsite receptors and individuals intruding onto the site after closure. In addition, uncertainty analyses were performed. Results of calculations made using nominal data indicate that the radiological doses will be below appropriate radiological criteria throughout operations and after closure of the facility. Recommendations were made for future performance assessment calculations.

Radioactive Waste Management Complex performance assessment: Draft

International Nuclear Information System (INIS)

Case, M.J.; Maheras, S.J.; McKenzie-Carter, M.A.; Sussman, M.E.; Voilleque, P.

1990-06-01

A radiological performance assessment of the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory was conducted to demonstrate compliance with appropriate radiological criteria of the US Department of Energy and the US Environmental Protection Agency for protection of the general public. The calculations involved modeling the transport of radionuclides from buried waste, to surface soil and subsurface media, and eventually to members of the general public via air, ground water, and food chain pathways. Projections of doses were made for both offsite receptors and individuals intruding onto the site after closure. In addition, uncertainty analyses were performed. Results of calculations made using nominal data indicate that the radiological doses will be below appropriate radiological criteria throughout operations and after closure of the facility. Recommendations were made for future performance assessment calculations

Low-level waste disposal site performance assessment with the RQ/PQ methodology. Final report

International Nuclear Information System (INIS)

Rogers, V.C.; Grant, M.W.; Sutherland, A.A.

1982-12-01

A methodology called RQ/PQ (retention quotient/performance quotient) has been developed for relating the potential hazard of radioactive waste to the natural and man-made barriers provided by a disposal facility. The methodology utilizes a systems approach to quantify the safety of low-level waste disposed in a near-surface facility. The main advantages of the RQ/PQ methodology are its simplicity of analysis and clarity of presentation while still allowing a comprehensive set of nuclides and pathways to be treated. Site performance and facility designs for low-level waste disposal can be easily investigated with relatively few parameters needed to define the problem. Application of the methodology has revealed that the key factor affecting the safety of low-level waste disposal in near surface facilities is the potential for intrusion events. Food, inhalation and well water pathways dominate in the analysis of such events. While the food and inhalation pathways are not strongly site-dependent, the well water pathway is. Finally, burial at depths of 5 m or more was shown to reduce the impacts from intrusion events

Engineering assessment of inactive uranium mill tailings, Spook site, Converse County, Wyoming

International Nuclear Information System (INIS)

1981-10-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Spook site in order to revise the December 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings 48 mi northeast of Casper, in Converse County, Wyoming. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 187,000 tons of tailings at the Spook site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover makes and gamma densitometers for measuring cross-sectionally averaged mass velocity in steady steam-water flow are presented. The results are interpreted ntation

Engineering assessment of inactive uranium mill tailings, Spook site, Converse County, Wyoming

Energy Technology Data Exchange (ETDEWEB)

1981-10-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Spook site in order to revise the December 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings 48 mi northeast of Casper, in Converse County, Wyoming. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 187,000 tons of tailings at the Spook site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover makes and gamma densitometers for measuring cross-sectionally averaged mass velocity in steady steam-water flow are presented. The results are interpreted ntation.

Preliminary risk assessment of Power Plant Plomin site contaminated by radioactive slag and ash

International Nuclear Information System (INIS)

Skanata, D.; Sinka, D.; Lokner, V.; Schaller, A.

1996-01-01

There is a certain number of radioactively contaminated sites in the Republic of Croatia, one of them being known as Power Plant Plomin site, which contains radioactive slag and ash. Due to a relatively high quantity of the deposited material, as well as relatively high population density of the neighbouring area, it is very important to assess the impact of the site on human health and environment. Using RESRAD computer code and PATHRAE method a preliminary assessment of doses and radiation risks for the workers who spend most of their working day at the pile has been performed. PATHRAE method has also been used for the assessment of radiation risks for the neighbouring population. The assessment is preliminary in its character due to the lack of input data. On the basis of assessment results, recommendations are being given comprising measurements to be taken with a view to coming up with the final risk assessment, as well as protective measures which should be undertaken in the meantime. (author)

Interim report - geotechnical site assessment methodology. Vol.1

International Nuclear Information System (INIS)

Tunbridge, L.W.; Richards, L.R.

1983-05-01

An interim report summarizing the research conducted on geotechnical site assessment methodology at the Carwynnen test mine in Cornwall. The geological setting of the test site in the Cornubian granite batholith is described. The effect of structure imposed by discontinuities on the engineering behaviour of rock masses is discussed and the scanline survey method of obtaining data on discontinuities in the rock mass is described. The requirement for remote geophysical methods of characterizing the mass is discussed and initial experiments using seismic and ultrasonic velocity measurements are reported. Computer programs to perform statistical analysis of the discontinuity patterns are described. Overcoring and hydraulic fracturing methods of determining the in-situ stress are briefly described and the results of a programme of in-situ stress measurements using the overcoring method are reported. (author)

Confidence assessment. Site descriptive modelling SDM-Site Forsmark

International Nuclear Information System (INIS)

2008-09-01

The objective of this report is to assess the confidence that can be placed in the Forsmark site descriptive model, based on the information available at the conclusion of the surface-based investigations (SDM-Site Forsmark). In this exploration, an overriding question is whether remaining uncertainties are significant for repository engineering design or long-term safety assessment and could successfully be further reduced by more surface based investigations or more usefully by explorations underground made during construction of the repository. The confidence in the Forsmark site descriptive model, based on the data available at the conclusion of the surface-based site investigations, have been assessed by exploring: Confidence in the site characterisation data base; Key remaining issues and their handling; Handling of alternative models; Consistency between disciplines; and, Main reasons for confidence and lack of confidence in the model. It is generally found that the key aspects of importance for safety assessment and repository engineering of the Forsmark site descriptive model are associated with a high degree of confidence. Because of the robust geological model that describes the site, the overall confidence in Forsmark site descriptive model is judged to be high. While some aspects have lower confidence this lack of confidence is handled by providing wider uncertainty ranges, bounding estimates and/or alternative models. Most, but not all, of the low confidence aspects have little impact on repository engineering design or for long-term safety. Poor precision in the measured data are judged to have limited impact on uncertainties on the site descriptive model, with the exceptions of inaccuracy in determining the position of some boreholes at depth in 3-D space, as well as the poor precision of the orientation of BIPS images in some boreholes, and the poor precision of stress data determined by overcoring at the locations where the pre

Performance assessment - risk assessment vive la differences

International Nuclear Information System (INIS)

Nitschke, R.L.

1997-01-01

In the sister worlds of radioactive waste management disposal and environmental restoration, there are two similar processes and computational approaches for determining the acceptability of the proposed activities. While similar, these two techniques can lead to confusion and misunderstanding if the differences are not recognized and appreciated. In the case of radioactive waste management, the performance assessment process is used to determine compliance with certain prescribed 'performance objectives'. These objectives are designed to ensure that the disposal of radioactive (high-level, low-level, and/or transuranic) waste will be protective of human health and the environment. The environmental link is primarily through assuring protection of the groundwater as a resource. In the case of environmental restoration, the risk assessment process is used to determine the proper remedial action response, if any, for a past hazardous waste release. The process compares the 'no action' or 'leave as is' option with both carcinogenic and noncarcinogenic values for human health to determine the need for any action and to help to help determine just what the appropriate action would need to be. The impacts to the ecological system are evaluated in a slightly, different but similar fashion. Now the common objectives between these two processes notwithstanding. There are some key and fundamental differences that need to be answered that make direct comparisons or a common approach inappropriate. Failure to recognize this can lead to confusion and misunderstanding. This can be particularly problematic when one is faced with an active disposal facility located within the boundaries of an environmental restoration site as is the case at the Idaho National Engineering Laboratory (INEL). Through a critical evaluation of the performance assessment and risk assessment processes, highlighting both similarities and differences, it is hoped that greater understanding and appreciation

Assessment of mixed hazardous and radioactive waste sites at Hanford

International Nuclear Information System (INIS)

McLaughlin, T.J.; Cramer, K.H.; Lamar, D.A.; Sherwood, D.R.; Stenner, R.D.; Schulze, W.B.

1987-10-01

The US Department of Energy and Pacific Northwest Laboratory recently completed a preliminary assessment of 685 inactive hazardous waste sites located on the Hanford Site. The preliminary assessment involved collecting historical data and individual site information, conducting site inspections, and establishing an environmental impact priority, using the Hazard Ranking System, for each of these 685 sites. This preliminary assessment was the first step in the remediation process required by the Comprehensive Environmental Response, Compensation and Liability Act. This paper presents the results of that preliminary assessment. 10 refs., 4 figs., 1 tab

Overview of a performance assessment methodology for low-level radioactive waste disposal facilities

International Nuclear Information System (INIS)

Kozak, M.W.; Chu, M.S.Y.

1991-01-01

A performance assessment methodology has been developed for use by the US Nuclear Regulatory Commission in evaluating license applications for low-level waste disposal facilities. This paper provides a summary and an overview of the modeling approaches selected for the methodology. The overview includes discussions of the philosophy and structure of the methodology. This performance assessment methodology is designed to provide the NRC with a tool for performing confirmatory analyses in support of license reviews related to postclosure performance. The methodology allows analyses of dose to individuals from off-site releases under normal conditions as well as on-site doses to inadvertent intruders. 24 refs., 1 tab

Improvement of Off-site Dose Assessment Code for Operating Nuclear Power Plant

Energy Technology Data Exchange (ETDEWEB)

Kim, Juyub; Kim, Juyoul; Shin, Kwangyoung [FNC Technology Co. Ltd., Yongin (Korea, Republic of); You, Songjae; Moon, Jongyi [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

2014-05-15

XOQDOQ code which calculates atmospheric Dispersion factor was included into INDAC also. A research on the improvement of off-site dose assessment system for an operating nuclear power plant was performed by KINS in 2011. As a result, following improvements were derived: - Separation of dose assessment for new and existing facilities - Update of food ingestion data - Consideration of multi-unit operation and so on In order to reflect the results, INDAC is under modification. INDAC is an integrated dose assessment code for an operating nuclear power plant and consists of three main modules: XOQDOQ, GASDOS and LIQDOS. The modules are under modification in order to improve the accuracy of assessment and usability. Assessment points for multi-unit release can be calculated through the improved code and the method on dose assessment for multi-unit release has been modified, so that the dose assessment result of multi-unit site becomes more realistic by relieving excessive conservatism. Finally, as the accuracy of calculation modules has been improved, the reliability of dose assessment result has been strengthened.

Baseline risk assessment of groundwater contamination at the Uranium Mill Tailings Site near Gunnison, Colorado

International Nuclear Information System (INIS)

1994-04-01

This report evaluates potential impacts to public health or the environment resulting from groundwater contamination at the former uranium mill processing site. The tailings and other contaminated material at this site are being placed in an off-site disposal cell by the US Department of Energy's (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating groundwater contamination. This is the second risk assessment of groundwater contamination at this site. The first risk assessment was performed primarily to evaluate existing domestic wells to determine the potential for immediate human health and environmental impacts. This risk assessment evaluates the most contaminated groundwater that flows beneath the processing site towards the Gunnison River. The monitor wells that have consistently shown the highest concentration of most contaminants are used in this risk assessment. This risk assessment will be used in conjunction with additional activities and documents to assist in determining what remedial action is needed for contaminated groundwater at the site after the tailings are relocated. This risk assessment follows an approach outlined by the US Environmental Protection Agency (EPA). The first step is to evaluate groundwater data collected from monitor wells at the site. Evaluation of these data showed that the main contaminants in the groundwater are cadmium, cobalt, iron, manganese, sulfate, uranium, and some of the products of radioactive decay of uranium

Engineering assessment of inactive uranium mill tailings, Durango Site, Durango, Colorado

International Nuclear Information System (INIS)

1981-06-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Durango site in order to revise the November 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Durango, Colorado. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the nearly 1.6 million tons of tailings at the Durango site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite and off-site decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II through IV). Cost estimates for the seven options range from about $10,700,000 for stabilization in-place, to about $21,800,000 for disposal at a distance of about 10 mi. Three principal alternatives for the reprocessing of the Durango tailings were examined: (a) heap leaching; (b) treatment at an existing mill; and (c) reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $30/lb U 3 O 8 by either heap leach or conventional plant processes

Patient Self-Assessment of Surgical Site Infection is Inaccurate.

Science.gov (United States)

Richter, Vered; Cohen, Matan J; Benenson, Shmuel; Almogy, Gideon; Brezis, Mayer

2017-08-01

Availability of surgical site infection (SSI) surveillance rates challenges clinicians, healthcare administrators and leaders and the public. The purpose of this report is to demonstrate the consequences patient self-assessment strategies have on SSI reporting rates. We performed SSI surveillance among patients undergoing general surgery procedures, including telephone follow-up 30 days after surgery. Additionally we undertook a separate validation study in which we compared patient self-assessments of SSI with surgeon assessment. Finally, we performed a meta-analysis of similar validation studies of patient self-assessment strategies. There were 22/266 in-hospital SSIs diagnosed (8.3%), and additional 16 cases were detected through the 30-day follow-up. In total, the SSI rate was 16.8% (95% CI 10.1-18.5). In the validation survey, we found patient telephone surveillance to have a sensitivity of 66% (95% CI 40-93%) and a specificity of 90% (95% CI 86-94%). The meta-analysis included five additional studies. The overall sensitivity was 83.3% (95% CI 79-88%), and the overall specificity was 97.4% (95% CI 97-98%). Simulation of the meta-analysis results divulged that when the true infection rate is 1%, reported rates would be 4%; a true rate of 50%, the reported rates would be 43%. Patient self-assessment strategies in order to fulfill 30-day SSI surveillance misestimate SSI rates and lead to an erroneous overall appreciation of inter-institutional variation. Self-assessment strategies overestimate SSIs rate of institutions with high-quality performance and underestimate rates of poor performance. We propose such strategies be abandoned. Alternative strategies of patient follow-up strategies should be evaluated in order to provide valid and reliable information regarding institutional performance in preventing patient harm.

Tiger Team Assessment of the Savannah River Site: Appendices

International Nuclear Information System (INIS)

1990-06-01

This draft document contains findings identified during the Tiger Team Compliance Assessment of the US Department of Energy Savannah River Site (SRS), located in three countries (Aiken, Barnwell and Allendale), South Carolina. The Assessment was directed by the Department's Office of the Assistant Secretary for Environment, Safety, and Health (ES ampersand H) and was conducted from January 29 to March 23, 1990. The Savannah River Site Tiger Team Compliance Assessment was broad in scope covering the Environment, Safety and Health, and Management areas and was designed to determine the site's compliance with applicable Federal (including DOE), state, and local regulations and requirements. The scope of the Environmental assessment was sitewide while the Safety and Health assessments included site operating facilities (except reactors), and the sitewide elements of Aviation Safety, Emergency Preparedness, Medical Services, and Packaging and Transportation. This report contains the appendices to the assessment

Tiger team assessment of the Argonne Illinois site

International Nuclear Information System (INIS)

1990-01-01

This report documents the results of the Department of Energy's (DOE) Tiger Team Assessment of the Argonne Illinois Site (AIS) (including the DOE Chicago Operations Office, DOE Argonne Area Office, Argonne National Laboratory-East, and New Brunswick Laboratory) and Site A and Plot M, Argonne, Illinois, conducted from September 17 through October 19, 1990. The Tiger Team Assessment was conducted by a team comprised of professionals from DOE, contractors, consultants. The purpose of the assessment was to provide the Secretary of Energy with the status of Environment, Safety, and Health (ES ampersand H) Programs at AIS. Argonne National Laboratory-East (ANL-E) is the principal tenant at AIS. ANL-E is a multiprogram laboratory operated by the University of Chicago for DOE. The mission of ANL-E is to perform basic and applied research that supports the development of energy-related technologies. There are a significant number of ES ampersand H findings and concerns identified in the report that require prompt management attention. A significant change in culture is required before ANL-E can attain consistent and verifiable compliance with statutes, regulations and DOE Orders. ES ampersand H activities are informal, fragmented, and inconsistently implemented. Communication is seriously lacking, both vertically and horizontally. Management expectations are not known or commondated adequately, support is not consistent, and oversight is not effective

Tiger team assessment of the Argonne Illinois site

Energy Technology Data Exchange (ETDEWEB)

1990-10-19

This report documents the results of the Department of Energy's (DOE) Tiger Team Assessment of the Argonne Illinois Site (AIS) (including the DOE Chicago Operations Office, DOE Argonne Area Office, Argonne National Laboratory-East, and New Brunswick Laboratory) and Site A and Plot M, Argonne, Illinois, conducted from September 17 through October 19, 1990. The Tiger Team Assessment was conducted by a team comprised of professionals from DOE, contractors, consultants. The purpose of the assessment was to provide the Secretary of Energy with the status of Environment, Safety, and Health (ES H) Programs at AIS. Argonne National Laboratory-East (ANL-E) is the principal tenant at AIS. ANL-E is a multiprogram laboratory operated by the University of Chicago for DOE. The mission of ANL-E is to perform basic and applied research that supports the development of energy-related technologies. There are a significant number of ES H findings and concerns identified in the report that require prompt management attention. A significant change in culture is required before ANL-E can attain consistent and verifiable compliance with statutes, regulations and DOE Orders. ES H activities are informal, fragmented, and inconsistently implemented. Communication is seriously lacking, both vertically and horizontally. Management expectations are not known or commondated adequately, support is not consistent, and oversight is not effective.

A Bayesian belief network approach for assessing uncertainty in conceptual site models at contaminated sites

Science.gov (United States)

Thomsen, Nanna I.; Binning, Philip J.; McKnight, Ursula S.; Tuxen, Nina; Bjerg, Poul L.; Troldborg, Mads

2016-05-01

A key component in risk assessment of contaminated sites is in the formulation of a conceptual site model (CSM). A CSM is a simplified representation of reality and forms the basis for the mathematical modeling of contaminant fate and transport at the site. The CSM should therefore identify the most important site-specific features and processes that may affect the contaminant transport behavior at the site. However, the development of a CSM will always be associated with uncertainties due to limited data and lack of understanding of the site conditions. CSM uncertainty is often found to be a major source of model error and it should therefore be accounted for when evaluating uncertainties in risk assessments. We present a Bayesian belief network (BBN) approach for constructing CSMs and assessing their uncertainty at contaminated sites. BBNs are graphical probabilistic models that are effective for integrating quantitative and qualitative information, and thus can strengthen decisions when empirical data are lacking. The proposed BBN approach facilitates a systematic construction of multiple CSMs, and then determines the belief in each CSM using a variety of data types and/or expert opinion at different knowledge levels. The developed BBNs combine data from desktop studies and initial site investigations with expert opinion to assess which of the CSMs are more likely to reflect the actual site conditions. The method is demonstrated on a Danish field site, contaminated with chlorinated ethenes. Four different CSMs are developed by combining two contaminant source zone interpretations (presence or absence of a separate phase contamination) and two geological interpretations (fractured or unfractured clay till). The beliefs in each of the CSMs are assessed sequentially based on data from three investigation stages (a screening investigation, a more detailed investigation, and an expert consultation) to demonstrate that the belief can be updated as more information

Technical summary of the Performance Assessment Calculational Exercises for 1990 (PACE-90)

International Nuclear Information System (INIS)

Barnard, R.W.; Dockery, H.A.

1991-06-01

A Performance Assessment Calculational Exercise for 1990 (PACE-90) was coordinated by the Yucca Mountain Site Characterization Project Office for a total-system performance-assessment problem. The primary objectives of the exercise were to develop performance-assessment computational capabilities of the Yucca Mountain Project participates and to aid in identifying critical elements and processes associated with the calculation. The problem defined for PACE-90 was simulation of a ''nominal case'' groundwater flow and transport of a selected group of radionuclides through a portion of Yucca Mountain. Both 1-D and 2-D calculations were run for a modeling period of 100,000 years. The nuclides used, 99 Tc, 135 Cs, 129 I, and 237 Np, were representative of ''classes'' of long-lived nuclides expected to be present in the waste inventory. Movement of the radionuclides was simulated through a detailed hydrostratigraphy developed from Yucca Mountain data specifically for this exercise. The results showed that, for the specified conditions with the conceptual models used in the problem, no radioactive contamination reached the water table, 230 m below the repository. However, due to the unavailability of sufficient site-specific data, the results of this exercise cannot be considered a comprehensive total-system- performance assessment of the Yucca Mountain site as a high-level- waste repository. 46 refs., 94 figs., 19 tabs

A rapid stability assessment of China's IGS sites after the Ms7. 0 Lushan earthquake

Directory of Open Access Journals (Sweden)

Meng Jie

2013-05-01

Full Text Available A rapid and accurate assessment of the stability of surveying and mapping reference points is important for post – disaster rescue, disaster relief and reconstruction activities. Using Precise Point Positioning (PPP technology, a rapid assessment of the stability of the IGS sites in China was performed after the Ms 7. 0 Lushan earthquake using rapid precise ephemeris and rapid precise satellite clock products. The results show that the earthquake had a very small impact and did not cause significant permanent deformation at the IGS sites. Most of the sites were unaffected and remained stable after the earthquake.

Evaluating the adequacy of a reference site pool for ecological assessments in environmentally complex regions

Science.gov (United States)

Ode, Peter R.; Rehn, Andrew C.; Mazor, Raphael D.; Schiff, Kenneth C.; Stein, Eric D.; May, Jason; Brown, Larry R.; Herbst, David B.; Gillette, D.D.; Lunde, Kevin; Hawkins, Charles P.

2016-01-01

Many advances in the field of bioassessment have focused on approaches for objectively selecting the pool of reference sites used to establish expectations for healthy waterbodies, but little emphasis has been placed on ways to evaluate the suitability of the reference-site pool for its intended applications (e.g., compliance assessment vs ambient monitoring). These evaluations are critical because an inadequately evaluated reference pool may bias assessments in some settings. We present an approach for evaluating the adequacy of a reference-site pool for supporting biotic-index development in environmentally heterogeneous and pervasively altered regions. We followed common approaches for selecting sites with low levels of anthropogenic stress to screen 1985 candidate stream reaches to create a pool of 590 reference sites for assessing the biological integrity of streams in California, USA. We assessed the resulting pool of reference sites against 2 performance criteria. First, we evaluated how well the reference-site pool represented the range of natural gradients present in the entire population of streams as estimated by sites sampled through probabilistic surveys. Second, we evaluated the degree to which we were successful in rejecting sites influenced by anthropogenic stress by comparing biological metric scores at reference sites with the most vs fewest potential sources of stress. Using this approach, we established a reference-site pool with low levels of human-associated stress and broad coverage of environmental heterogeneity. This approach should be widely applicable and customizable to particular regional or programmatic needs.

Dose assessment from potential radionuclide emissions from stacks on the Hanford Site

International Nuclear Information System (INIS)

Davis, W.E.; Barnett, J.M.

1995-04-01

On February 3, 1993, the US Department of Energy, Richland Operations Office (RL), received a Compliance Order and Information Request from the Director of the Air and Toxics Division of the US Environmental Protection Agency (EPA), Region 10. The Compliance Order required RL to (1) evaluate all radionuclide emission points at the Hanford Site to determine which points are subject to the continuous emission sampling requirements of Title 40, Code of Federal Regulations, Part 61 (40 CFR 61), Subpart H, and (2) continuously sample radionuclide emissions in accordance with requirements in 40 CFR 61.93. The Information Request required RL to provide a written Compliance Plan to meet the requirements of the Compliance Order. A Compliance Plan was submitted to EPA, Region 10, on April 30, 1993. The Compliance Plan specified that a dose assessment would be performed for 84 Westinghouse Hanford Company (WHC) stacks registered with the Washington State Department of Health on the Hanford Site. Any stack identified in the assessment as having potential emissions to cause an effective dose equivalent (EDE) to a maximum exposed individual (MEI) greater than 0.1 mrem y -1 must have a compliant sampling system. In addition, a Federal Facility Compliance Agreement (FFCA) was signed on. February 7, 1994. The FFCA required that all unregistered stacks on the Hanford Site be assessed. This requirement increased the number of stacks to be assessed to 123 stacks. Six methods for performing the assessments are described. An initial assessment using only the HEPA filtration factor for back calculations identified 32 stacks that would have emissions which would cause an EDE to the MEI greater than 0.1 mrem y -1 . When the other methods were applied the number was reduced to 20 stacks. The paper discusses reasons for these overestimates

2011 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada National Security Site, Nye County, Nevada: Review of the Performance Assessments and Composite Analyses

International Nuclear Information System (INIS)

2012-01-01

The Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site (National Security Technologies, LLC, 2007a) requires an annual review to assess the adequacy of the Performance Assessments (PAs) and Composite Analyses (CAs), with the results submitted annually to U.S. Department of Energy (DOE) Office of Environmental Management. The Disposal Authorization Statements for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) also require that such reviews be made and that secondary or minor unresolved issues be tracked and addressed as part of the maintenance plan (DOE, 1999a; 2000). The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office performed an annual review of the Area 3 and Area 5 RWMS PAs and CAs for fiscal year (FY) 2011. This annual summary report presents data and conclusions from the FY 2011 review, and determines the adequacy of the PAs and CAs. Operational factors (e.g., waste forms and containers, facility design, and waste receipts), closure plans, monitoring results, and research and development (R and D) activities were reviewed to determine the adequacy of the PAs. Likewise, the environmental restoration activities at the Nevada National Security Site (NNSS) (formerly the Nevada Test Site) relevant to the sources of residual radioactive material that are considered in the CAs, the land-use planning, and the results of the environmental monitoring and R and D activities were reviewed to determine the adequacy of the CAs. Important developments in FY 2011 include the following: (1) Operation of a new shallow land disposal unit and a new Resource Conservation and Recovery Act (RCRA)-compliant lined disposal unit at the Area 5 RWMS; (2) Development of new closure inventory estimates based on disposals through FY 2011; (3) Evaluation of new or revised waste streams by special analysis; (4) Development of

2011 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada National Security Site, Nye County, Nevada: Review of the Performance Assessments and Composite Analyses

Energy Technology Data Exchange (ETDEWEB)

NSTec Environmental Management

2012-03-20

The Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site (National Security Technologies, LLC, 2007a) requires an annual review to assess the adequacy of the Performance Assessments (PAs) and Composite Analyses (CAs), with the results submitted annually to U.S. Department of Energy (DOE) Office of Environmental Management. The Disposal Authorization Statements for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) also require that such reviews be made and that secondary or minor unresolved issues be tracked and addressed as part of the maintenance plan (DOE, 1999a; 2000). The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office performed an annual review of the Area 3 and Area 5 RWMS PAs and CAs for fiscal year (FY) 2011. This annual summary report presents data and conclusions from the FY 2011 review, and determines the adequacy of the PAs and CAs. Operational factors (e.g., waste forms and containers, facility design, and waste receipts), closure plans, monitoring results, and research and development (R and D) activities were reviewed to determine the adequacy of the PAs. Likewise, the environmental restoration activities at the Nevada National Security Site (NNSS) (formerly the Nevada Test Site) relevant to the sources of residual radioactive material that are considered in the CAs, the land-use planning, and the results of the environmental monitoring and R and D activities were reviewed to determine the adequacy of the CAs. Important developments in FY 2011 include the following: (1) Operation of a new shallow land disposal unit and a new Resource Conservation and Recovery Act (RCRA)-compliant lined disposal unit at the Area 5 RWMS; (2) Development of new closure inventory estimates based on disposals through FY 2011; (3) Evaluation of new or revised waste streams by special analysis; (4) Development of

Dose assessment for potential radionuclide emissions from stacks on the Hanford Site: NESHAP compliance

International Nuclear Information System (INIS)

Davis, W.E.; Barnett, J.M.; Kenoyer, J.L.

1994-03-01

The purpose of this document is to present the assessment results for the registered stacks on the Hanford Site for potential emissions, i.e. emissions with no control devices in place. Further, the document will identify those stacks requiring continuous monitoring, i.e. the effective dose equivalent from potential emissions >0.1 mrem/yr. The stack assessment of potential emissions was performed on 84 registered stacks on the Hanford Site. These emission sources represent individual point sources presently registered under Washington Administrative code 246-247 with the Washington Department of Health. The methods used in assessing the potential emissions from the stacks are described

Riel Converter Station, Winnipeg: Site selection and environmental assessment status report

International Nuclear Information System (INIS)

1991-01-01

As part of its expansion plans, Manitoba Hydro is planning to construct a converter station east of Winnipeg to receive power from a 850-km dc transmission line which will be constructed to bring power from a new generating station in the north of the province. Work performed to date on site selection and preliminary environmental assessment of the converter station is reviewed. The role of the converter station is described and the potential impacts are summarized in such areas as employment opportunities, pollution and noise during construction, electric and magnetic field effects, and land use impacts. Site selection criteria are outlined and potential sites are identified and evaluated. The Deacon site has been chosen as the preferred site since it has a number of inherent advantages including existing ownership by Manitoba Hydro, proximity to existing transmission rights-of-way, and low visual and land-use impact. 12 figs

Environmental assessment: Richton Dome site, Mississippi

International Nuclear Information System (INIS)

1986-05-01

In February 1983, the US Department of Energy (DOE) identified the Richton Dome site in Mississippi as one of the nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high-level radioactive waste. To determine their suitability, the Richton Dome site and the eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. These evaluations were reported in draft environmental assessments (EAs), which were issued for public review and comment. After considering the comments received on the draft EAs, the DOE prepared the final EAs. The site is in the Gulf interior region, which is one of five distinct geohydrologic settings considered for the first repository. This setting contains two other potentially acceptable sites--the Cypress Creek Dome site in Mississippi and the Vacherie Dome site in Louisiana. Although the Cypress Creek Dome and the Vacherie Dome sites are suitable for site characterization, the DOE has concluded that the Richton Dome site is the preferred site in the Gulf interior region. On the basis of the evaluations reported in this EA, the DOE has found that the Richton Dome site is not disqualified under the guidelines

Environmental assessment: Richton Dome Site, Mississippi

Energy Technology Data Exchange (ETDEWEB)

none,

1986-05-01

In February 1983, the US Department of Energy (DOE) identified the Richton Dome site in Mississippi as one of the nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high-level radioactive waste. To determine their suitability, the Richton Dome site and the eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. These evaluations were reported in draft environmental assessments (EAs), which were issued for public review and comment. After considering the comments received on the draft EAs, the DOE prepared the final EAs. The site is in the Gulf interior region, which is one of five distinct geohydrologic settings considered for the first repository. This setting contains two other potentially acceptable sites--the Cypress Creek Dome site in Mississippi and the Vacherie Dome site in Louisiana. Although the Cypress Creek Dome and the Vacherie Dome sites are suitable for site characterization, the DOE has concluded that the Richton Dome site is the preferred site in the Gulf interior region. On the basis of the evaluations reported in this EA, the DOE has found that the Richton Dome site is not disqualified under the guidelines.

Environmental assessment: Richton Dome site, Mississippi

Energy Technology Data Exchange (ETDEWEB)

none,

1986-05-01

In February 1983, the US Department of Energy (DOE) identified the Richton Dome site in Mississippi as one of the nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high-level radioactive waste. To determine their suitability, the Richton Dome site and the eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. These evaluations were reported in draft environmental assessments (EAs), which were issued for public review and comment. After considering the comments received on the draft EAs, the DOE prepared the final EAs. The site is in the Gulf interior region, which is one of five distinct geohydrologic settings considered for the first repository. This setting contains two other potentially acceptable sites--the Cypress Creek Dome site in Mississippi and the Vacherie Dome site in Louisiana. Although the Cypress Creek Dome and the Vacherie Dome sites are suitable for site characterization, the DOE has concluded that the Richton Dome site is the preferred site in the Gulf interior region. On the basis of the evaluations reported in this EA, the DOE has found that the Richton Dome site is not disqualified under the guidelines.

Environmental assessment: Richton Dome Site, Mississippi

International Nuclear Information System (INIS)

1986-05-01

In February 1983, the US Department of Energy (DOE) identified the Richton Dome site in Mississippi as one of the nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high-level radioactive waste. To determine their suitability, the Richton Dome site and the eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. These evaluations were reported in draft environmental assessments (EAs), which were issued for public review and comment. After considering the comments received on the draft EAs, the DOE prepared the final EAs. The site is in the Gulf interior region, which is one of five distinct geohydrologic settings considered for the first repository. This setting contains two other potentially acceptable sites--the Cypress Creek Dome site in Mississippi and the Vacherie Dome site in Louisiana. Although the Cypress Creek Dome and the Vacherie Dome sites are suitable for site characterization, the DOE has concluded that the Richton Dome site is the preferred site in the Gulf interior region. On the basis of the evaluations reported in this EA, the DOE has found that the Richton Dome site is not disqualified under the guidelines

Radionuclide transport report for the safety assessment SR-Site

Energy Technology Data Exchange (ETDEWEB)

2010-12-15

This document compiles radionuclide transport calculations of a KBS-3 repository for the safety assessment SR-Site. The SR-Site assessment supports the licence application for a final repository at Forsmark, Sweden

7 CFR 1948.83 - Performance of site development work.

Science.gov (United States)

2010-01-01

... 7 Agriculture 13 2010-01-01 2009-01-01 true Performance of site development work. 1948.83 Section 1948.83 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE... Development Assistance Program § 1948.83 Performance of site development work. Site development work will be...

Quality assessment in in vivo NMR spectroscopy: IV. A multicentre trial of test objects and protocols for performance assessment in clinical NMR spectroscopy

DEFF Research Database (Denmark)

Keevil, S.F.; Barbiroli, B; Collins, D.J.

1995-01-01

implemented on commercially available MR systems at ten sites in Europe. At each site, a number of parameters devised by the Concerted Action were measured using prototype test objects. Some of these parameters related to the quality of localisation and others to the overall performance of the spectrometer...... in the development of the Concerted Action's final recommendations for MRS performance assessment, and demonstrate that such assessment provides valuable information in the comparison of spectroscopy data from different sites and in the development of new localisation sequences, and provides a means of quality...... assurance in MRS...

Tiger Team Assessment of the Oak Ridge K-25 Site

International Nuclear Information System (INIS)

1991-12-01

The Office of Special Projects in the Office of the Assistant Secretary for Environment, Safety, and Health (EH) has the responsibility to conduct Tiger Team Assessments for the Secretary of Energy. This report documents the Tiger Team Assessment of the Oak Ridge K-25 Site (K-25 Site), Oak Ridge, Tennessee. The purpose of the Assessment is to provide the Secretary of Energy with concise information on the: current ES ampersand H compliance status of the Site and the vulnerabilities associated with that compliance status; root causes for noncompliance; adequacy of DOE and site contractor ES ampersand H management programs; adequacy of response actions developed to address identified problem areas; and adequacy of ES ampersand H self-assessments and the institutionalization of the self-assessment process at the K-25 Site

Spent fuel as a waste form: Data needs to allow long term performance assessment under repository disposal conditions

International Nuclear Information System (INIS)

Oversby, V.M.

1986-12-01

Performance assessment calculations are required for high level waste repositories for a period of 10,000 years. The Siting Guidelines require a comparison of sites following site characterization and prior to final site selection to be made over a 100,000 year period. To perform the required calculations, a detailed knowledge of the physical and chemical processes that affect waste form performance will be needed for each site. This paper will review the factors that affect the release of radionuclides from spent fuel under repository conditions, summarize our present state of knowledge, and suggest areas where more work is needed to support the performance assessment calculations. 17 refs., 5 figs., 3 tabs

Use of toxicity assessment to develop site specific remediation criteria for oil and gas facilities : guidance manual

International Nuclear Information System (INIS)

1996-01-01

The results of a two year study into the evaluation of toxicity-based methods to develop site-specific, risk-based cleanup objectives for the decommissioning of oil and gas facilities were compiled into a manual of guidance. The two basic approaches used in determining remediation criteria for contaminated sites are: (1) comparison of the concentrations of chemicals found on-site with broad regional or national soil and water quality objectives developed for the chemicals involved, and (2) site-specific risk assessment. Toxicity tests are used to test organisms such as earthworms, lettuce seeds, or larval fish directly in the soil, water or sediment suspected of being contaminated. The effects of any contamination on the survival, growth, reproduction, and behaviour of the test organisms are then evaluated. The manual provides guidance in: (1) using toxicity assessments within the regulatory framework of site decommissioning, (2) performing a toxicity assessment, and (3) developing site-specific criteria for a risk assessment. 18 refs., 3 tabs., 5 figs

Hanford Site Cleanup Challenges and Opportunities for Science and Technology - A Strategic Assessment

International Nuclear Information System (INIS)

Johnson, W.; Reichmuth, B.; Wood, T.; Glasper, M.; Hanson, J.

2002-01-01

. Hanford was the first site where such a unique, comprehensive assessment was performed. This paper provides a means to share this approach with other sites and to introduce Hanford's S and T challenges to potential technology providers and other interested parties

Summary of the engineering assessment of inactive uranium-mill tailings, Bowman Site, Bowman, North Dakota

International Nuclear Information System (INIS)

1981-11-01

Ford, Bacon and Davis Utah Inc. has performed an engineering assessment of the problems resulting from the existence of radioactive residues from the burning of uranium-bearing lignite at Bowman, North Dakota. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of ash residues and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 97,000 tons of ash and contaminated materials at the Bowman site constitutes a significant environmental impact, although windblown ash and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the contaminated materials to remote disposal sites and decontamination of the ashing site (Options II through IV). Cost estimates for the four options range from about $1,740,000 for stabilization in-place, to about $3,060,000 for disposal at a distance of about 4 mi. Reprocessing the ash for uranium recovery is not feasible because of the extremely small amount of material available at the site and because of its low U 3 O 8 content

A study on development of monitoring and assessment module for sites

International Nuclear Information System (INIS)

Park, Se Moon; Yoon, Bong Yo; Kim, Dae Jung; Park, Joo Wan; Kim, Chang Lak

2006-01-01

As the development of total management systems for sites along with site environmental information is becoming standard, the system known as the Site Information and Total Environmental database management System (SITES) has been developed over the last two years. The first result was a database management system for storing data obtained from facilities, and a site characterization in addition to an environmental assessment of a site. The SITES database is designed to be effective and practical for use with facility management and safety assessment in relation to Geographic Information Systems. SITES is a total management program, which includes its database, its data analysis system required for site characterization, a safety assessment modeling system and an environment monitoring system. I can contribute to the institutional management of the facility and to its safety reassessment. SITES is composed of two main modules: the SITES Database Module (SDM) and the Monitoring and Assessment (M and A) module. The M and A module is subdivided into two sub-modules: the Safety Assessment System (SAS) and the Site Environmental Monitoring System (SEMS). SAS controls the data (input and output) from the SITES DB for the site safety assessment, whereas SEMS controls the data obtained from the records of the measuring sensors and facilities. The on-line site and environmental monitoring data is managed in SEMS. The present paper introduces the procedure and function of the M and A modules

Modular risk analysis for assessing multiple waste sites

International Nuclear Information System (INIS)

Whelan, G.; Buck, J.W.; Nazarali, A.

1994-06-01

Human-health impacts, especially to the surrounding public, are extremely difficult to assess at installations that contain multiple waste sites and a variety of mixed-waste constituents (e.g., organic, inorganic, and radioactive). These assessments must address different constituents, multiple waste sites, multiple release patterns, different transport pathways (i.e., groundwater, surface water, air, and overland soil), different receptor types and locations, various times of interest, population distributions, land-use patterns, baseline assessments, a variety of exposure scenarios, etc. Although the process is complex, two of the most important difficulties to overcome are associated with (1) establishing an approach that allows for modifying the source term, transport, or exposure component as an individual module without having to re-evaluate the entire installation-wide assessment (i.e., all modules simultaneously), and (2) displaying and communicating the results in an understandable and useable maimer to interested parties. An integrated, physics-based, compartmentalized approach, which is coupled to a Geographical Information System (GIS), captures the regional health impacts associated with multiple waste sites (e.g., hundreds to thousands of waste sites) at locations within and surrounding the installation. Utilizing a modular/GIS-based approach overcomes difficulties in (1) analyzing a wide variety of scenarios for multiple waste sites, and (2) communicating results from a complex human-health-impact analysis by capturing the essence of the assessment in a relatively elegant manner, so the meaning of the results can be quickly conveyed to all who review them

Occupational radiation dose assessment for a non site specific spent fuel storage facility

International Nuclear Information System (INIS)

Hadley, J.; Eble, R.G. Jr.

1997-01-01

To expedite the licensing process of the non site specific Centralized Interim Storage Facility (CISF) the Department of Energy has completed a phase I CISF Topical Safety Analysis Report (TSAR). The TSAR will be used in licensing the phase I CISF if a site is designated. An occupational radiation does assessment of the facility operations is performed as part of the phase I CISF design. The first phase of the CISF has the capability to receive, transfer, and store SNF in dual-purpose cask/canister systems (DPC's). Currently there are five vendor technologies under consideration. The preliminary dose assessment is based on estimated occupational exposures using traditional power plant ISFSI and transport cask handling processes. The second step in the process is to recommend ALARA techniques to reduce potential exposures. A final dose assessment is completed implementing the ALARA techniques and a review is performed to ensure that the design is in compliance with regulatory criteria. The dose assessment and ALARA evaluation are determined using the following input information: Dose estimates from vendor SAR's; ISFSI experience with similar systems; Traditional methods of operations; Expected CISF cask receipt rates; and feasible ALARA techniques. 5 refs., 1 tab

Epibenthic Assessment of a Renewable Tidal Energy Site

Directory of Open Access Journals (Sweden)

Emma V. Sheehan

2013-01-01

Full Text Available Concern over global climate change as a result of fossil fuel use has resulted in energy production from renewable sources. Marine renewable energy devices provide clean electricity but can also cause physical disturbance to the local environment. There is a considerable paucity of ecological data at potential marine renewable energy sites that is needed to assess potential future impacts and allow optimal siting of devices. Here, we provide a baseline benthic survey for the Big Russel in Guernsey, UK, a potential site for tidal energy development. To assess the suitability of proposed sites for marine renewable energy in the Big Russel and to identify potential control sites, we compared species assemblages and habitat types. This baseline survey can be used to select control habitats to compare and monitor the benthic communities after installation of the device and contribute towards the optimal siting of any future installation.

The Waste Isolation Pilot Plant Performance Assessment Program

International Nuclear Information System (INIS)

Myers, J.; Coons, W.E.; Eastmond, R.; Morse, J.; Chakrabarti, S.; Zurkoff, J.; Colton, I.D.; Banz, I.

1986-01-01

The Waste Isolation Pilot Plant (WIPP) Performance Assessment Program involves a comprehensive analysis of the WIPP project with respect to the recently finalized Environmental Protection Agency regulations regarding the long-term geologic isolation of radioactive wastes. The performance assessment brings together the results of site characterization, underground experimental, and environmental studies into a rigorous determination of the performance of WIPP as a disposal system for transuranic radioactive waste. The Program consists of scenario development, geochemical, hydrologic, and thermomechanical support analyses and will address the specific containment and individual protection requirements specified in 40 CFR 191 sub-part B. Calculated releases from these interrelated analyses will be reported as an overall probability distribution of cumulative release resulting from all processes and events occurring over the 10,000 year post-closure period. In addition, results will include any doses to the public resulting from natural processes occurring over the 1,000 year post-closure period. The overall plan for the WIPP Performance Assessment Program is presented along with approaches to issues specific to the WIPP project

Fuels and Materials Examination Facility: Environmental assessment, Hanford site, Richland, Washington: Environmental assessment

International Nuclear Information System (INIS)

1980-07-01

The Fuels and Materials Examination Facility (FMEF) and the High Performance Fuel Laboratory (HPFL) were originally proposed to be constructed as separate facilities in the 400 Area of the Hanford Site near Richland, Washington. The environmental effects of these two facilities were described and evaluated in the FMEF Environmental Assessment and the HPFL Final Environmental Impact Statement, ERDA-1550. For economic reasons, the two facilities will no longer be built as separate facilities. The FMEF facility plans have been modified to incorporate some of the features of the proposed HPFL facility while retaining essentially all of the capabilities of the original FMEF proposal. The purpose of this document is to update the FMEF Environmental Assessment to appropriately reflect addition of certain HPFL features into the FMEF facility and to assess the environmental affects of the facility which resulted from inclusion of HPFL features into the FMEF facility

Engineering assessment of inactive uranium mill tailings: Lakeview site, Lakeview, Oregon

International Nuclear Information System (INIS)

1981-10-01

This assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The three alternative actions presented in this engineering assessment include millsite decontamination with the addition of 3 m of stabilization cover material (Option I) and removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II and III). Cost estimates range from about $6,000,000 for stabilization in-place, to about $7,500,000 for disposal at a distance of about 10 miles. Three alternatives for reprocessing the Lakeview tailings were examined: heap leaching, treatment at an existing mill, and reprocessing at a new conventional mill. The cost of the uranium recovered would be over $450/lb of U 3 O 8 and hence reprocessing is not economical

Engineering assessment of inactive uranium mill tailings: Lakeview site, Lakeview, Oregon

Energy Technology Data Exchange (ETDEWEB)

None

1981-10-01

This assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The three alternative actions presented in this engineering assessment include millsite decontamination with the addition of 3 m of stabilization cover material (Option I) and removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II and III). Cost estimates range from about $6,000,000 for stabilization in-place, to about $7,500,000 for disposal at a distance of about 10 miles. Three alternatives for reprocessing the Lakeview tailings were examined: heap leaching, treatment at an existing mill, and reprocessing at a new conventional mill. The cost of the uranium recovered would be over $450/lb of U/sub 3/O/sub 8/ and hence reprocessing is not economical.

Even Faster Web Sites Performance Best Practices for Web Developers

CERN Document Server

Souders, Steve

2009-01-01

Performance is critical to the success of any web site, and yet today's web applications push browsers to their limits with increasing amounts of rich content and heavy use of Ajax. In this book, Steve Souders, web performance evangelist at Google and former Chief Performance Yahoo!, provides valuable techniques to help you optimize your site's performance. Souders' previous book, the bestselling High Performance Web Sites, shocked the web development world by revealing that 80% of the time it takes for a web page to load is on the client side. In Even Faster Web Sites, Souders and eight exp

Seismic assessment of a site using the time series method

International Nuclear Information System (INIS)

Krutzik, N.J.; Rotaru, I.; Bobei, M.; Mingiuc, C.; Serban, V.; Androne, M.

2001-01-01

1. To increase the safety of a NPP located on a seismic site, the seismic acceleration level to which the NPP should be qualified must be as representative as possible for that site, with a conservative degree of safety but not too exaggerated. 2. The consideration of the seismic events affecting the site as independent events and the use of statistic methods to define some safety levels with very low annual occurrence probabilities (10 -4 ) may lead to some exaggerations of the seismic safety level. 3. The use of some very high values for the seismic accelerations imposed by the seismic safety levels required by the hazard analysis may lead to very expensive technical solutions that can make the plant operation more difficult and increase the maintenance costs. 4. The consideration of seismic events as a time series with dependence among the events produced may lead to a more representative assessment of a NPP site seismic activity and consequently to a prognosis on the seismic level values to which the NPP would be ensured throughout its life-span. That prognosis should consider the actual seismic activity (including small earthquakes in real time) of the focuses that affect the plant site. The method is useful for two purposes: a) research, i.e. homogenizing the history data basis by the generation of earthquakes during periods lacking information and correlation of the information with the existing information. The aim is to perform the hazard analysis using a homogeneous data set in order to determine the seismic design data for a site; b) operation, i.e. the performance of a prognosis on the seismic activity on a certain site and consideration of preventive measures to minimize the possible effects of an earthquake. 5. The paper proposes the application of Autoregressive Time Series to issue a prognosis on the seismic activity of a focus and presents the analysis on Vrancea focus that affects Cernavoda NPP site by this method. 6. The paper also presents the

Geosphere process report for the safety assessment SR-Site

International Nuclear Information System (INIS)

Skagius, Kristina

2010-11-01

This report documents geosphere processes identified as relevant to the long-term safety of a KBS-3 repository, and forms an important part of the reporting of the safety assessment SR-Site. The detailed assessment methodology, including the role of the process reports in the assessment, is described in the SR-Site Main report /SKB 2011/

Geosphere process report for the safety assessment SR-Site

Energy Technology Data Exchange (ETDEWEB)

Skagius, Kristina (ed.) (Kemakta Konsult AB, Stockholm (Sweden))

2010-11-15

This report documents geosphere processes identified as relevant to the long-term safety of a KBS-3 repository, and forms an important part of the reporting of the safety assessment SR-Site. The detailed assessment methodology, including the role of the process reports in the assessment, is described in the SR-Site Main report /SKB 2011/

Performance Art at the Campusphere: Pedagogical Experiments On-Site

Science.gov (United States)

Ben-Shaul, Daphna

2018-01-01

Following a unique practice and research laboratory entitled "Performance: Site/Self" that took place in 2013-2015, this article discusses the implementation of performance art at an academic site--the Tel Aviv University campus. This pedagogical and artistic initiative, characterised by the transgressive pedagogy of performance art…

Low-level waste disposal performance assessments - Total source-term analysis

Energy Technology Data Exchange (ETDEWEB)

Wilhite, E.L.

1995-12-31

Disposal of low-level radioactive waste at Department of Energy (DOE) facilities is regulated by DOE. DOE Order 5820.2A establishes policies, guidelines, and minimum requirements for managing radioactive waste. Requirements for disposal of low-level waste emplaced after September 1988 include providing reasonable assurance of meeting stated performance objectives by completing a radiological performance assessment. Recently, the Defense Nuclear Facilities Safety Board issued Recommendation 94-2, {open_quotes}Conformance with Safety Standards at Department of Energy Low-Level Nuclear Waste and Disposal Sites.{close_quotes} One of the elements of the recommendation is that low-level waste performance assessments do not include the entire source term because low-level waste emplaced prior to September 1988, as well as other DOE sources of radioactivity in the ground, are excluded. DOE has developed and issued guidance for preliminary assessments of the impact of including the total source term in performance assessments. This paper will present issues resulting from the inclusion of all DOE sources of radioactivity in performance assessments of low-level waste disposal facilities.

Environmental assessment: Davis Canyon site, Utah

International Nuclear Information System (INIS)

1986-05-01

In February 1983, the US Department of Energy (DOE) identified the Davis Canyon site in Utah as one of the nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high-level radioactive waste. To determine their suitability, the Davis Canyon site and the eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. These evaluations were reported in draft environmental assessments (EAs), which were issued for public review and comment. After considering the comments received on the draft EAs, the DOE prepared the final EA. The Davis Canyon site is in the Paradox Basin, which is one of five distinct geohydrologic settings considered for the first repository. This setting contains one other potentially acceptable site -- the Lavender Canyon site. Although the Lavender Canyon site is suitable for site characterization, the DOE has concluded that the Davis Canyon site is the preferred site in the Paradox Basin. On the basis of the evaluations reported in this EA, the DOE has found that the Davis Canyon site is not disqualified under the guidelines. Furthermore, the DOE has fond that the site is suitable for site characterization because the evidence does not support a conclusion that the site will not be able to meet each of the qualifying conditions specified in the guidelines. On the basis of these findings, the DOE is nominating the Davis Canyon site as one of five sites suitable for characterization. 181 figs., 175 tabs

Environmental assessment: Davis Canyon site, Utah

Energy Technology Data Exchange (ETDEWEB)

none,

1986-05-01

In February 1983, the US Department of Energy (DOE) identified the Davis Canyon site in Utah as one of the nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high- level radioactive waste. To determine their suitability, the Davis Canyon site and the eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. These evaluations were reported in draft environmental assessments (EAs), which were issued for public review and comment. After considering the comments received on the draft EAs, the DOE prepared the final EA. The Davis Canyon site is in the Paradox Basin, which is one of five distinct geohydrologic settings considered for the first repository. This setting contains one other potentially acceptable site -- the Lavender Canyon site. Although the Lavender Canyon site is suitable for site characterization, the DOE has concluded that the Davis Canyon site is the preferred site in the Paradox Basin. On the basis of the evaluations reported in this EA, the DOE has found that the Davis Canyon site is not disqualified under the guidelines. Furthermore, the DOE has found that the site is suitable for site characterization because the evidence does not support a conclusion that the site will not be able to meet each of the qualifying conditions specified in the guidelines. On the basis of these findings, the DOE is nominating the Davis Canyon site as one of the five sites suitable for characterization.

Environmental assessment: Davis Canyon site, Utah

Energy Technology Data Exchange (ETDEWEB)

none,

1986-05-01

In February 1983, the US Department of Energy (DOE) identified the Davis Canyon site in Utah as one of the nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high-level radioactive waste. To determine their suitability, the Davis Canyon site and the eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. These evaluations were reported in draft environmental assessments (EAs), which were issued for public review and comment. After considering the comments received on the draft EAs, the DOE prepared the final EA. The Davis Canyon site is in the Paradox Basin, which is one of five distinct geohydrologic settings considered for the first repository. This setting contains one other potentially acceptable site -- the Lavender Canyon site. Although the Lavender Canyon site is suitable for site characterization, the DOE has concluded that the Davis Canyon site is the preferred site in the Paradox Basin. On the basis of the evaluations reported in this EA, the DOE has found that the Davis Canyon site is not disqualified under the guidelines. Furthermore, the DOE has fond that the site is suitable for site characterization because the evidence does not support a conclusion that the site will not be able to meet each of the qualifying conditions specified in the guidelines. On the basis of these findings, the DOE is nominating the Davis Canyon site as one of five sites suitable for characterization. 181 figs., 175 tabs.

Environmental assessment: Davis Canyon site, Utah

Energy Technology Data Exchange (ETDEWEB)

none,

1986-05-01

In February 1983, the US Department of Energy (DOE) identified the Davis Canyon site in Utah as one of the nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high-level radioactive waste. To determine their suitability, the Davis Canyon site and the eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. These evaluations were reported in draft environmental assessments (EAs), which were issued for public review and comment. After considering the comments received on the draft EAs, the DOE prepared the final EA. The Davis Canyon site is in the Paradox Basin, which is one of five distinct geohydrologic settings considering for the first repository. This setting contains one other potentially acceptable site -- the Lavender Canyon site. Although the Lavender Canyon site is suitable for site characterization, the DOE has concluded that the Davis Canyon site is the preferred site in the Paradox Basin. On the basis of the evaluations reported in this EA, the DOE has found that the Davis Canyon site is not disqualified under the guidelines. Furthermore, the DOE has found that the site is suitable for site characterization because the evidence does not support a conclusion that the site will not be able to meet each of the qualifying conditions specified in the guidelines. On the basis of these findings, the DOE is nominating the Davis Canyon site as one of five sites suitable for characterization.

Environmental assessment: Davis Canyon site, Utah

International Nuclear Information System (INIS)

1986-05-01

In February 1983, the US Department of Energy (DOE) identified the Davis Canyon site in Utah as one of the nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high-level radioactive waste. To determine their suitability, the Davis Canyon site and the eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. These evaluations were reported in draft environmental assessments (EAs), which were issued for public review and comment. After considering the comments received on the draft EAs, the DOE prepared the final EA. The Davis Canyon site is in the Paradox Basin, which is one of five distinct geohydrologic settings considering for the first repository. This setting contains one other potentially acceptable site -- the Lavender Canyon site. Although the Lavender Canyon site is suitable for site characterization, the DOE has concluded that the Davis Canyon site is the preferred site in the Paradox Basin. On the basis of the evaluations reported in this EA, the DOE has found that the Davis Canyon site is not disqualified under the guidelines. Furthermore, the DOE has found that the site is suitable for site characterization because the evidence does not support a conclusion that the site will not be able to meet each of the qualifying conditions specified in the guidelines. On the basis of these findings, the DOE is nominating the Davis Canyon site as one of five sites suitable for characterization

Environmental assessment: Davis Canyon site, Utah

International Nuclear Information System (INIS)

1986-05-01

In February 1983, the US Department of Energy (DOE) identified the Davis Canyon site in Utah as one of the nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high- level radioactive waste. To determine their suitability, the Davis Canyon site and the eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. These evaluations were reported in draft environmental assessments (EAs), which were issued for public review and comment. After considering the comments received on the draft EAs, the DOE prepared the final EA. The Davis Canyon site is in the Paradox Basin, which is one of five distinct geohydrologic settings considered for the first repository. This setting contains one other potentially acceptable site -- the Lavender Canyon site. Although the Lavender Canyon site is suitable for site characterization, the DOE has concluded that the Davis Canyon site is the preferred site in the Paradox Basin. On the basis of the evaluations reported in this EA, the DOE has found that the Davis Canyon site is not disqualified under the guidelines. Furthermore, the DOE has found that the site is suitable for site characterization because the evidence does not support a conclusion that the site will not be able to meet each of the qualifying conditions specified in the guidelines. On the basis of these findings, the DOE is nominating the Davis Canyon site as one of the five sites suitable for characterization

Summary of the engineering assessment of radioactive sands and residues, Lowman Site, Lowman, Idaho

International Nuclear Information System (INIS)

1981-09-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Lowman site in order to revise the December 1977 engineering assessment of the problems resulting from the existence of radioactive sands and residues at Lowman, Idaho. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of radioactive sands and residues and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 191,000 tons of radioactive sands, residues, and contaminated soils at the Lowman site constitutes the most significant environmental impact, although windblown radioactive sands and external gamma radiation also are factors

Environmental assessment of ground-water compliance activities at the Uranium Mill Tailings Site, Spook, Wyoming

International Nuclear Information System (INIS)

1997-02-01

This report assesses the environmental impacts of the Uranium Mill Tailings Site at Spook, Wyoming on ground water. DOE previously characterized the site and monitoring data were collected during the surface remediation. The ground water compliance strategy is to perform no further remediation at the site since the ground water in the aquifer is neither a current nor potential source of drinking water. Under the no-action alternative, certain regulatory requirements would not be met

2012 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada National Security Site, Nye County, Nevada: Review of the Performance Assessments and Composite Analyses

Energy Technology Data Exchange (ETDEWEB)

Shott, G. [National Security Technologies, LLC

2013-03-18

The Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site (National Security Technologies, LLC 2007a) requires an annual review to assess the adequacy of the performance assessments (PAs) and composite analyses (CAs), with the results submitted to the U.S. Department of Energy (DOE) Office of Environmental Management. The Disposal Authorization Statements for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) also require that such reviews be made and that secondary or minor unresolved issues be tracked and addressed as part of the maintenance plan (DOE 1999a, 2000). The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office performed an annual review of the Area 3 and Area 5 RWMS PAs and CAs for fiscal year (FY) 2012. This annual summary report presents data and conclusions from the FY 2012 review, and determines the adequacy of the PAs and CAs. Operational factors (e.g., waste forms and containers, facility design, and waste receipts), closure plans, monitoring results, and research and development (R&D) activities were reviewed to determine the adequacy of the PAs. Likewise, the environmental restoration activities at the Nevada National Security Site (NNSS) relevant to the sources of residual radioactive material that are considered in the CAs, the land-use planning, and the results of the environmental monitoring and R&D activities were reviewed to determine the adequacy of the CAs. Important developments in FY 2012 include the following: Release of a special analysis for the Area 3 RWMS assessing the continuing validity of the PA and CA; Development of a new Area 5 RWMS closure inventory estimate based on disposals through FY 2012; Evaluation of new or revised waste streams by special analysis; and Development of version 4.114 of the Area 5 RWMS GoldSim PA model. The Area 3 RWMS has been in inactive status since

Environment, Safety and Health Progress Assessment of the Hanford Site

International Nuclear Information System (INIS)

1992-05-01

This report documents the result of the US Department of Energy (DOE) Environment, Safety and Health (ES ampersand H) Progress Assessment of the Hanford Site, in Richland, Washington. The assessment, which was conducted from May 11 through May 22, 1992, included a selective-review of the ES ampersand H management systems and programs of the responsible DOE Headquarters Program Offices the DOE Richland Field Office, and the site contractors. The ES ampersand H Progress Assessments are part of the Secretary of Energy's continuing effort to institutionalize line management accountability and the self-assessment process throughout DOE and its contractor organizations. The purpose of the Hanford Site ES ampersand H Progress Assessment is to provide the Secretary with an independent assessment of the adequacy and effectiveness of the DOE and contractor management structures, resources, and systems to address ES ampersand H problems and requirements. They are not intended to be comprehensive compliance assessments of ES ampersand H activities. The point of reference for assessing programs at the Hanford Site was, for the most part, the Tiger Team Assessment of the Hanford Site, which was conducted from May 21 through July 18, 1990. A summary of issues and progress in the areas of environment, safety and health, and management is included

Total system performance assessment - 1995: An evaluation of the potential Yucca Mountain repository

International Nuclear Information System (INIS)

Atkins, J.E.; Lee, J.H.; Lingineni, S.; Mishra, S.; McNeish, J.A.; Sassani, D.C.; Sevougian, S.D.

1995-11-01

The U.S. Department of Energy (DOE) is currently investigating the feasibility of permanently disposing the nation's commercial high-level radioactive wastes (in the form of spent fuel from the over 100 electric power-generating nuclear reactors across the U.S.) and a portion of the defense high-level radioactive wastes (currently stored at federal facilities around the country) in the unsaturated tuffaceous rocks at Yucca Mountain, Nevada. Quantitative predictions based on the most current understanding of the processes and parameters potentially affecting the long-term behavior of the disposal system are used to assess the ability of the site and its associated engineered designs to meet regulatory objectives of the US NRC and the US EPA. The evaluation of the ability of the overall system to meet the performance objectives specified in the applicable regulatory standards has been termed total system performance assessment (TSPA). Total system performance assessments require the explicit quantification of the relevant processes and process interactions. In addition assessments are useful to help define the most significant processes, the information gaps and uncertainties and therefore the additional information required for more robust and defensible assessment of the overall performance. The aim of any total system performance assessment is to be as complete and reasonably conservative as possible and to assure that the descriptions of the predictive models and parameters are sufficient to ascertain their accuracy. Total system performance assessments evolve with time. Previous iterations of total system performance assessment of the Yucca Mountain site and associated engineered barriers have been conducted in 1991 and 1993

Total system performance assessment - 1995: An evaluation of the potential Yucca Mountain repository

Energy Technology Data Exchange (ETDEWEB)

Atkins, J.E.; Lee, J.H.; Lingineni, S.; Mishra, S; McNeish, J.A.; Sassani, D.C.; Sevougian, S.D.

1995-11-01

The U.S. Department of Energy (DOE) is currently investigating the feasibility of permanently disposing the nation`s commercial high-level radioactive wastes (in the form of spent fuel from the over 100 electric power-generating nuclear reactors across the U.S.) and a portion of the defense high-level radioactive wastes (currently stored at federal facilities around the country) in the unsaturated tuffaceous rocks at Yucca Mountain, Nevada. Quantitative predictions based on the most current understanding of the processes and parameters potentially affecting the long-term behavior of the disposal system are used to assess the ability of the site and its associated engineered designs to meet regulatory objectives of the US NRC and the US EPA. The evaluation of the ability of the overall system to meet the performance objectives specified in the applicable regulatory standards has been termed total system performance assessment (TSPA). Total system performance assessments require the explicit quantification of the relevant processes and process interactions. In addition assessments are useful to help define the most significant processes, the information gaps and uncertainties and therefore the additional information required for more robust and defensible assessment of the overall performance. The aim of any total system performance assessment is to be as complete and reasonably conservative as possible and to assure that the descriptions of the predictive models and parameters are sufficient to ascertain their accuracy. Total system performance assessments evolve with time. Previous iterations of total system performance assessment of the Yucca Mountain site and associated engineered barriers have been conducted in 1991 and 1993.

Environmental assessment, Deaf Smith County site, Texas

Energy Technology Data Exchange (ETDEWEB)

1986-05-01

The Nuclear Waste Policy Act of 1982 (42 USC sections 10101-10226) requires the environmental assessment of a proposed site to include a statement of the basis for nominating a site as suitable for characterization. Volume 2 provides a detailed statement evaluating the site suitability of the Deaf Smith County Site under DOE siting guidelines, as well as a comparison of the Deaf Smith County Site to the other sites under consideration. The evaluation of the Deaf Smith County Site is based on the impacts associated with the reference repository design, but the evaluation will not change if based on the Mission Plan repository concept. The second part of this document compares the Deaf Smith County Site to Davis Canyon, Hanford, Richton Dome and Yucca Mountain. This comparison is required under DOE guidelines and is not intended to directly support subsequent recommendation of three sites for characterization as candidate sites. 259 refs., 29 figs., 66 refs. (MHB)

Environmental assessment, Deaf Smith County site, Texas

International Nuclear Information System (INIS)

1986-05-01

The Nuclear Waste Policy Act of 1982 (42 USC sections 10101-10226) requires the environmental assessment of a proposed site to include a statement of the basis for nominating a site as suitable for characterization. Volume 2 provides a detailed statement evaluating the site suitability of the Deaf Smith County Site under DOE siting guidelines, as well as a comparison of the Deaf Smith County Site to the other sites under consideration. The evaluation of the Deaf Smith County Site is based on the impacts associated with the reference repository design, but the evaluation will not change if based on the Mission Plan repository concept. The second part of this document compares the Deaf Smith County Site to Davis Canyon, Hanford, Richton Dome and Yucca Mountain. This comparison is required under DOE guidelines and is not intended to directly support subsequent recommendation of three sites for characterization as candidate sites. 259 refs., 29 figs., 66 refs

Geotechnical site assessment methodology

International Nuclear Information System (INIS)

Tunbridge, L.W.; Richards, L.R.

1985-09-01

A final report summarizing the research conducted on geotechnical site assessment methodology at the Carwynnen test mine in Cornwall. The geological setting of the test site in the Cornubian granite batholith is described. The effect of structure imposed by discontinuities on the engineering behaviour of rock masses is discussed and the scanline survey method of obtaining data on discontinuities in the rock mass is described. The applicability of some methods of statistical analysis for discontinuity data is reviewed. The requirement for remote geophysical methods of characterizing the mass is discussed and experiments using seismic and ultrasonic velocity measurements are reported. Methods of determining the in-situ stresses are described and the final results of a programme of in-situ stress measurements using the overcoring and hydrofracture methods are reported. (author)

Monitoring the performance of off-site processors

International Nuclear Information System (INIS)

Miller, C.C.

1995-01-01

Commercial nuclear power plants have been able to utilize the latest technologies and achieve large volume reduction by obtaining off-site waste processor services. Although the use of such services reduce the burden of waste processing it also reduces the utility's control over the process. Monitoring the performance of off-site processors is important so that the utility is cognizant of the waste disposition for required regulatory reporting. In addition to obtaining data for Reg Guide 1.21 reporting, Performance monitoring is important to determine which vendor and which services to utilize. Off-site processor services were initially offered for the decontamination of metallic waste. Since that time the list of services has expanded to include supercompaction, survey for release, incineration and metal melting. The number of vendors offering off-site services has increased and the services they offer vary. processing rates vary between vendors and have different charge bases. Determining which vendor to use for what service can be complicated and confusing

The MULTIMEDIA exposure model as a risk assessment tool at LUST sites

International Nuclear Information System (INIS)

Bowers, R.B.

1994-01-01

In the course of characterizing Leaking Underground Storage Tank (LUST) sites in the Commonwealth, Virginia Department of Environmental Quality (VDEQ) regulations section 6.5.A.2.b of VR-680-13-02, requires that a risk assessment be performed which must address, among other issues, aqueous phase contaminant exposure levels to critical receptors. often, during the course of conducting such an assessment, the aqueous phase contaminant plume has not yet intercepted the critical down gradient receptor. Thus, the determination of the maximum potential exposure level to this receptor can only be made through the use of an appropriate fate and transport model. This paper focuses on an application of the saturated zone module of the USEPA's MULTIMEDIA Exposure Assessment model. The case study presented involves a LUST site in the Commonwealth, in which four critical receptors of leaded gasoline contaminated groundwater were identified. These receptors included three residential water wells and an intermittent stream. At this particular site, the aqueous phase contaminant plume had not yet reached any of the receptors; and the MULTIMEDIA model was employed to predict the steady-state aqueous phase concentrations with very favorable results

Formerly Utilized Sites Remedial Action Program environmental compliance assessment checklists

Energy Technology Data Exchange (ETDEWEB)

Levine, M.B.; Sigmon, C.F.

1989-09-29

The purpose of the Environmental Compliance Assessment Program is to assess the compliance of Formerly Utilized Site Remedial Action Program (FUSRAP) sites with applicable environmental regulations and Department of Energy (DOE) Orders. The mission is to identify, assess, and decontaminate sites utilized during the 1940s, 1950s, and 1960s to process and store uranium and thorium ores in support of the Manhattan Engineer District and the Atomic Energy Commission. To conduct the FUSRAP environmental compliance assessment, checklists were developed that outline audit procedures to determine the compliance status of the site. The checklists are divided in four groups to correspond to these regulatory areas: Hazardous Waste Management, PCB Management, Air Emissions, and Water Discharges.

Formerly Utilized Sites Remedial Action Program environmental compliance assessment checklists

International Nuclear Information System (INIS)

Levine, M.B.; Sigmon, C.F.

1989-01-01

The purpose of the Environmental Compliance Assessment Program is to assess the compliance of Formerly Utilized Site Remedial Action Program (FUSRAP) sites with applicable environmental regulations and Department of Energy (DOE) Orders. The mission is to identify, assess, and decontaminate sites utilized during the 1940s, 1950s, and 1960s to process and store uranium and thorium ores in support of the Manhattan Engineer District and the Atomic Energy Commission. To conduct the FUSRAP environmental compliance assessment, checklists were developed that outline audit procedures to determine the compliance status of the site. The checklists are divided in four groups to correspond to these regulatory areas: Hazardous Waste Management, PCB Management, Air Emissions, and Water Discharges

Assessing reservoir performance risk in CO2 storage projects

International Nuclear Information System (INIS)

Bowden, A.R.; Rigg, A.

2005-01-01

One of the main issues for researchers involved with geological storage of carbon dioxide (CO 2 ) has been the development of a proper methodology to assess and compare alternative CO 2 injection projects on the basis of risk. Consideration needs to be given to technical aspects, such as the risk of leakage and the effectiveness of the intended reservoir, as well as less tangible aspects such as the value and safety of geological storage of CO 2 , and potential impacts on the community and environment. The Geological Disposal of Carbon Dioxide (GEODISC), was a research program of the Australian Petroleum Cooperative Research Centre which identified 56 potential environmentally sustainable sites for CO 2 injection (ESSCIs) within Australia. Several studies were carried out, involving detailed evaluation of the suitability of 4 selected sites, including Dongara, Petrel, Gippsland and Carnarvon. The GEODISC program included a risk assessment research module which required a complete and quantified risk assessment of CO 2 injection as a storage option. Primary goals were to assess the risk of leakage, to assess the effectiveness of the intended reservoir, and to assess negative consequences to facilitate comparison of alternative sites. This paper discussed the background and risk assessment model. Key performance indicators (KPIs) were also developed to address the purpose of risk assessment. It was concluded that the RISQUE method is an appropriate approach and that potential injection projects can be measured against six KPIs including containment; effectiveness; self-funding potential; wider community benefits; community safety and community amenity. 6 refs., 3 tabs., 3 figs

Engineering assessment of inactive uranium mill tailings, Tube City site, Tuba City, Arizona

International Nuclear Information System (INIS)

1981-09-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Tuba City site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Tuba City, Arizona. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 0.8 million tons of tailings at the Tuba City site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material (Option I), to rterial (Option I), to rema densitometers for measuring cross-sectionally averaged mass velocity in steady steam-water flow are presented. The results are interpreted ntation

Radiological/toxicological sabotage assessments at the Savannah River Site

International Nuclear Information System (INIS)

Johnson, H.D.; Pascal, M.D.; Richardson, D.L.

1995-01-01

This paper describes the methods being employed by Westinghouse Savannah River Company (WSRC) to perform graded assessments of radiological and toxicological sabotage vulnerability at Savannah River Site (SRS) facilities. These assessments are conducted to ensure that effective measures are in place to prevent, mitigate, and respond to a potential sabotage event which may cause an airborne release of radiological/toxicological material, causing an adverse effect on the health and safety of employees, the public, and the environment. Department of Energy (DOE) Notice 5630.3A, open-quotes Protection of Departmental Facilities Against Radiological and Toxicological Sabotage,close quotes and the associated April 1993 DOE-Headquarters guidance provide the requirements and outline an eight-step process for hazardous material evaluation. The process requires the integration of information from a variety of disciplines, including safety, safeguards and security, and emergency preparedness. This paper summarizes WSRC's approach towards implementation of the DOE requirements, and explains the inter-relationships between the Radiological and Toxicological Assessments developed using this process, and facility Hazard Assessment Reports (HAs), Safety Analysis Reports (SARs), and Facility Vulnerability Assessments (VAs)

Probabilistic Seismic Hazard Assessment Method for Nonlinear Soil Sites based on the Hazard Spectrum of Bedrock Sites

International Nuclear Information System (INIS)

Hahm, Dae Gi; Seo, Jeong Moon; Choi, In Kil

2011-01-01

For the probabilistic safety assessment of the nuclear power plants (NPP) under seismic events, the rational probabilistic seismic hazard estimation should be performed. Generally, the probabilistic seismic hazard of NPP site is represented by the uniform hazard spectrum (UHS) for the specific annual frequency. In most case, since that the attenuation equations were defined for the bedrock sites, the standard attenuation laws cannot be applied to the general soft soil sites. Hence, for the probabilistic estimation of the seismic hazard of soft soil sites, a methodology of probabilistic seismic hazard analysis (PSHA) coupled with nonlinear dynamic analyses of the soil column are required. Two methods are commonly used for the site response analysis considering the nonlinearity of sites. The one is the deterministic method and another is the probabilistic method. In the analysis of site response, there exist many uncertainty factors such as the variation of the magnitude and frequency contents of input ground motion, and material properties of soil deposits. Hence, nowadays, it is recommended that the adoption of the probabilistic method for the PSHA of soft soil deposits considering such uncertainty factors. In this study, we estimated the amplification factor of the surface of the soft soil deposits with considering the uncertainties of the input ground motions and the soil material properties. Then, we proposed the probabilistic methodology to evaluate the UHS of the soft soil site by multiplying the amplification factor to that of the bedrock site. The proposed method was applied to four typical target sites of KNGR and APR1400 NPP site categories

Geochemical Data Package for Performance Assessment Calculations Related to the Savannah River Site

Energy Technology Data Exchange (ETDEWEB)

Kaplan, Daniel I. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-07-22

The Savannah River Site (SRS) disposes of low-level radioactive waste (LLW) and stabilizes high-level radioactive waste (HLW) tanks in the subsurface environment. Calculations used to establish the radiological limits of these facilities are referred to as Performance Assessments (PA), Special Analyses (SA), and Composite Analyses (CA). The objective of this document is to revise existing geochemical input values used for these calculations. This work builds on earlier compilations of geochemical data (2007, 2010), referred to a geochemical data packages. This work is being conducted as part of the on-going maintenance program of the SRS PA programs that periodically updates calculations and data packages when new information becomes available. Because application of values without full understanding of their original purpose may lead to misuse, this document also provides the geochemical conceptual model, the approach used for selecting the values, the justification for selecting data, and the assumptions made to assure that the conceptual and numerical geochemical models are reasonably conservative (i.e., bias the recommended input values to reflect conditions that will tend to predict the maximum risk to the hypothetical recipient). This document provides 1088 input parameters for geochemical parameters describing transport processes for 64 elements (>740 radioisotopes) potentially occurring within eight subsurface disposal or tank closure areas: Slit Trenches (ST), Engineered Trenches (ET), Low Activity Waste Vault (LAWV), Intermediate Level (ILV) Vaults, Naval Reactor Component Disposal Areas (NRCDA), Components-in-Grout (CIG) Trenches, Saltstone Facility, and Closed Liquid Waste Tanks. The geochemical parameters described here are the distribution coefficient, Kd value, apparent solubility concentration, k_s value, and the cementitious leachate impact factor.

Engineering assessment of inactive uranium mill tailings: Monument Valley Site, Monument Valley, Arizona

Energy Technology Data Exchange (ETDEWEB)

1981-10-01

Ford, Bacon and Davis Utah Inc. has reevalated the Monument Valley site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Monument Valley, Arizona. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposure of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 1.1 million tons of tailings at the Monument Valley site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II through IV). Cost estimates for the four options range from about $6,600,000 for stabilization in-place, to about $15,900,000 for disposal at a distance of about 15 mi. Three principal alternatives for reprocessing the Monument Valley tailings were examined: heap leaching; Treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovery is economically unattractive.

Engineering assessment of inactive uranium mill tailings: Monument Valley Site, Monument Valley, Arizona

International Nuclear Information System (INIS)

1981-10-01

Ford, Bacon and Davis Utah Inc. has reevalated the Monument Valley site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Monument Valley, Arizona. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposure of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 1.1 million tons of tailings at the Monument Valley site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II through IV). Cost estimates for the four options range from about $6,600,000 for stabilization in-place, to about $15,900,000 for disposal at a distance of about 15 mi. Three principal alternatives for reprocessing the Monument Valley tailings were examined: heap leaching; Treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovery is economically unattractive

Performance of a radioactive waste internment site

International Nuclear Information System (INIS)

Bernhardt, D.E.; Owen, D.H.; Mishub, R.J.; Prewett, S.V.; Cole, L.W.

1990-01-01

Aerojet disposed of 30,000 cubic meters of uranium and thorium wastes in an engineered 12,000 square meter (3 acre) internment site in Tennessee. The operation, performed under a State of Tennessee source material license, is based on termination of the license with the material remaining in place, and the option of future commercial use of the site. The closure plan included a long-term monitoring program. Yearly monitoring of the site has verified performance within the design criteria. Full-time construction monitored by a licensed engineer and extensive testing of materials ensured construction of the site according to or better than the specifications. Surface subsidence of the site has averaged about 2.2 cm with a range of 0 to 4.3 cm at 11 settlement markers after 4 years. The anticipated settlement, based on design parameters, was between 15 and 25 cm. The present anticipated settlement is 8 to 15 cm, based on the as-built parameters, and the long-term monitoring results. Slope stability analysis indicates the stability has improved with time due to consolidation of materials and reduced groundwater activity as a result of site construction. There has been no need for corrective action maintenance due to erosion, sluffing of slopes, or subsidence. Groundwater monitoring indicates the materials have been isolated, and there have also been no indications of springs or leakage from the site. 9 refs., 2 figs., 3 tabs

Baseline risk assessment of groundwater contamination at the Uranium Mill Tailings Site near Gunnison, Colorado. Revision 1

Energy Technology Data Exchange (ETDEWEB)

1994-04-01

This report evaluates potential impacts to public health or the environment resulting from groundwater contamination at the former uranium mill processing site. The tailings and other contaminated material at this site are being placed in an off-site disposal cell by the US Department of Energy`s (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating groundwater contamination. This is the second risk assessment of groundwater contamination at this site. The first risk assessment was performed primarily to evaluate existing domestic wells to determine the potential for immediate human health and environmental impacts. This risk assessment evaluates the most contaminated groundwater that flows beneath the processing site towards the Gunnison River. The monitor wells that have consistently shown the highest concentration of most contaminants are used in this risk assessment. This risk assessment will be used in conjunction with additional activities and documents to assist in determining what remedial action is needed for contaminated groundwater at the site after the tailings are relocated. This risk assessment follows an approach outlined by the US Environmental Protection Agency (EPA). The first step is to evaluate groundwater data collected from monitor wells at the site. Evaluation of these data showed that the main contaminants in the groundwater are cadmium, cobalt, iron, manganese, sulfate, uranium, and some of the products of radioactive decay of uranium.

FEP report for the safety assessment SR-Site

Energy Technology Data Exchange (ETDEWEB)

2010-12-15

This report documents the analysis and processing of features, events and processes, FEPs, that has been carried out within the safety assessment SR-Site, and forms an important part of the reporting of the project. The main part of the work was conducted within the earlier safety assessment SR-Can, which was a preparatory stage for the SR-Site assessment. The overall objective of the FEP analysis and processing in both SR-Can and SR-Site included development of a database of features, events and processes, an SKB FEP database, in a format that facilitates both a systematic analysis of FEPs and documentation of that FEP analysis, as well as facilitating revisions and updates to be made in connection with new safety assessments. The primary objective in SR-Site was to establish an SR-Site FEP catalogue within the framework of the SKB FEP database. This FEP catalogue was required to contain all FEPs that needed to be handled in SR-Site and is an update of the corresponding SR-Can FEP catalogue that was established for the SR-Can assessment. The starting point for the handling of FEPs in SR-Site was the SR-Can version of the SKB FEP database and associated SR-Can reports. The SR-Can version of the SKB FEP database includes the SR-Can FEP catalogue, as well as the sources for the identification of FEPs in SR-Can, namely the SR 97 processes and variables, Project FEPs in the NEA International FEP database version 1.2 and matrix interactions in the Interaction matrices developed for a deep repository of the KBS-3 type. Since the completion of the FEP work within SR-Can, an updated electronic version, version 2.1, of the NEA FEP database has become available. Compared with version 1.2 of the NEA FEP database, version 2.1 contains FEPs from two more projects. As part of SR-Site, all new Project FEPs in version 2.1 of the NEA FEP database have been mapped according to the methodology adopted in SR-Can resulting in an SR-Site version of the SKB FEP database. The SKB FEP

FEP report for the safety assessment SR-Site

International Nuclear Information System (INIS)

2010-12-01

This report documents the analysis and processing of features, events and processes, FEPs, that has been carried out within the safety assessment SR-Site, and forms an important part of the reporting of the project. The main part of the work was conducted within the earlier safety assessment SR-Can, which was a preparatory stage for the SR-Site assessment. The overall objective of the FEP analysis and processing in both SR-Can and SR-Site included development of a database of features, events and processes, an SKB FEP database, in a format that facilitates both a systematic analysis of FEPs and documentation of that FEP analysis, as well as facilitating revisions and updates to be made in connection with new safety assessments. The primary objective in SR-Site was to establish an SR-Site FEP catalogue within the framework of the SKB FEP database. This FEP catalogue was required to contain all FEPs that needed to be handled in SR-Site and is an update of the corresponding SR-Can FEP catalogue that was established for the SR-Can assessment. The starting point for the handling of FEPs in SR-Site was the SR-Can version of the SKB FEP database and associated SR-Can reports. The SR-Can version of the SKB FEP database includes the SR-Can FEP catalogue, as well as the sources for the identification of FEPs in SR-Can, namely the SR 97 processes and variables, Project FEPs in the NEA International FEP database version 1.2 and matrix interactions in the Interaction matrices developed for a deep repository of the KBS-3 type. Since the completion of the FEP work within SR-Can, an updated electronic version, version 2.1, of the NEA FEP database has become available. Compared with version 1.2 of the NEA FEP database, version 2.1 contains FEPs from two more projects. As part of SR-Site, all new Project FEPs in version 2.1 of the NEA FEP database have been mapped according to the methodology adopted in SR-Can resulting in an SR-Site version of the SKB FEP database. The SKB FEP

Current developments in the assessment of petroleum hydrocarbon contaminated sites: Analysis, interpretation, and use of the TPH parameter for quantitative risk assessment

International Nuclear Information System (INIS)

Garcia-Surette, M.; Maynard, P.; Lamie, P.O.; Kaslick, C.

1995-01-01

In 1994, the Massachusetts Department of Environmental Protection (MDEP) estimated that petroleum-only cases comprised approximately one-half of the state's hazardous waste sites currently under investigation and/or remediation. Because of this significant percentage, it became clear that assessing petroleum sites more efficiently in terms of risk and cleanup alternatives was necessary. One of these key MDEP policies describes an alternative risk assessment approach enabling the quantitative characterization of total petroleum hydrocarbon (TPH)-related health risks. The approach relies on the use of an analytical technique by which the mass of petroleum hydrocarbons within specified carbon ranges is quantified. MDEP's TPH risk assessment approach was successfully employed at a residential site contaminated with No. 2 fuel oil. The combined use of MDEP's suggested analytical methods, alternative reference compounds and toxicity values, as well as chromatograms, standard dose equations, and an EPA-approved box model, facilitated the performance of a more realistic and cost-effective assessment of risk. Such assessment provided key management information to regulatory agencies, and project managers, as well as property owners concerned with potential property value loss

Performance Assessment Program for the Savannah River Site Liquid Waste Facilities - 13610

Energy Technology Data Exchange (ETDEWEB)

Rosenberger, Kent H. [Savannah River Remediation LLC, Building 705-1C, Aiken, SC 29808 (United States)

2013-07-01

The Liquid Waste facilities at the U.S. Department of Energy's (DOE) Savannah River Site (SRS) are operated by Liquid Waste Operations contractor Savannah River Remediation LLC (SRR). A separate Performance Assessment (PA) is prepared to support disposal operations at the Saltstone Disposal Facility and closure evaluations for the two liquid waste tank farm facilities at SRS, F-Tank Farm and H-Tank Farm. A PA provides the technical basis and results to be used in subsequent documents to demonstrate compliance with the pertinent requirements identified in operations and closure regulatory guidance. The Saltstone Disposal Facility is subject to a State of South Carolina industrial solid waste landfill permit and the tank farms are subject to a state industrial waste water permit. The three Liquid Waste facilities are also subject to a Federal Facility Agreement approved by the State, DOE and the Environmental Protection Agency (EPA). Due to the regulatory structure, a PA is a key technical document reviewed by the DOE, the State of South Carolina and the EPA. As the waste material disposed of in the Saltstone Disposal Facility and the residual material in the closed tank farms is also subject to reclassification prior to closure via a waste determination pursuant to Section 3116 of the Ronald W. Reagan National Defense Authorization Act of Fiscal Year 2005, the U.S. Nuclear Regulatory Commission (NRC) is also a reviewing agency for the PAs. Pursuant to the Act, the NRC also has a continuing role to monitor disposal actions to assess compliance with stated performance objectives. The Liquid Waste PA program at SRS represents a continual process over the life of the disposal and closure operations. When the need for a PA or PA revision is identified, the first step is to develop a conceptual model to best represent the facility conditions. The conceptual model will include physical dimensions of the closed system, both the engineered and natural system, and

Performance Assessment Program for the Savannah River Site Liquid Waste Facilities - 13610

International Nuclear Information System (INIS)

Rosenberger, Kent H.

2013-01-01

The Liquid Waste facilities at the U.S. Department of Energy's (DOE) Savannah River Site (SRS) are operated by Liquid Waste Operations contractor Savannah River Remediation LLC (SRR). A separate Performance Assessment (PA) is prepared to support disposal operations at the Saltstone Disposal Facility and closure evaluations for the two liquid waste tank farm facilities at SRS, F-Tank Farm and H-Tank Farm. A PA provides the technical basis and results to be used in subsequent documents to demonstrate compliance with the pertinent requirements identified in operations and closure regulatory guidance. The Saltstone Disposal Facility is subject to a State of South Carolina industrial solid waste landfill permit and the tank farms are subject to a state industrial waste water permit. The three Liquid Waste facilities are also subject to a Federal Facility Agreement approved by the State, DOE and the Environmental Protection Agency (EPA). Due to the regulatory structure, a PA is a key technical document reviewed by the DOE, the State of South Carolina and the EPA. As the waste material disposed of in the Saltstone Disposal Facility and the residual material in the closed tank farms is also subject to reclassification prior to closure via a waste determination pursuant to Section 3116 of the Ronald W. Reagan National Defense Authorization Act of Fiscal Year 2005, the U.S. Nuclear Regulatory Commission (NRC) is also a reviewing agency for the PAs. Pursuant to the Act, the NRC also has a continuing role to monitor disposal actions to assess compliance with stated performance objectives. The Liquid Waste PA program at SRS represents a continual process over the life of the disposal and closure operations. When the need for a PA or PA revision is identified, the first step is to develop a conceptual model to best represent the facility conditions. The conceptual model will include physical dimensions of the closed system, both the engineered and natural system, and modeling

Phase II, Title I, engineering assessment of inactive uranium mill tailings, Riverton Site, Riverton, Wyoming

International Nuclear Information System (INIS)

1977-12-01

An engineering assessment was performed of the problems resulting from the existence of radioactive uranium mill tailings at the Spook Site, Converse County, Wyoming. Services include the performance of core drillings, soil, water and other sample analyses, radiometric measurements to determine areas with radium-contaminated materials, the evaluation of resulting radiation exposures of individuals and nearby populations, the investigation of site geology, hydrology, and meteorology and the evaluation and costing of alternative corrective actions. Radon gas release from the 187,000 tons of tailings at the Spook Site constitutes the main environmental impact, which is negligible. The two alternative actions presented are better fencing of the site in its present state, and placing tailings and contaminated on-site materials and soil in the open-pit mine and covering the resulting pile with 2 ft of overburden materials. The cost estimates for the options are $81,000 and $142,000, respectively

An assessment of the performance of municipal constructed wetlands in Ireland.

Science.gov (United States)

Hickey, Anthony; Arnscheidt, Joerg; Joyce, Eadaoin; O'Toole, James; Galvin, Gerry; O' Callaghan, Mark; Conroy, Ken; Killian, Darran; Shryane, Tommy; Hughes, Francis; Walsh, Katherine; Kavanagh, Emily

2018-03-15

While performance assessments of constructed wetlands sites around the world have appraised their capacity for effective removal of organics, a large variance remains in these sites' reported ability to retain nutrients, which appears to depend on differences in design, operation and climate factors. Nutrient retention is a very important objective for constructed wetlands, to avoid eutrophication of aquatic environments receiving their effluents. This study assessed the performance of constructed wetlands in terms of nutrient retention and associated parameters under the humid conditions of Ireland's temperate maritime climate. A review of the performance of 52 constructed wetland sites from 17 local authorities aimed to identify the best performing types of constructed wetlands and the treatment factors determining successful compliance with environmental standards. Data analysis compared effluent results from constructed wetlands with secondary free surface flow or tertiary horizontal subsurface flow, hybrid systems and integrated constructed wetlands with those from small-scale mechanical wastewater treatment plants of the same size class. Nutrient concentrations in effluents of constructed wetlands were negatively correlated (p treatment performance of constructed wetlands significantly (p wastewater treatment plants, secondary free surface water and tertiary horizontal subsurface flow wetlands showed a very large variance in effluent concentrations for organic and nutrient parameters. E. coli numbers in effluents were lowest for integrated constructed wetlands with an arithmetic mean of 89 MPN/100 ml. Despite Ireland's humid climate, some constructed wetland sites achieved long or frequent periods of zero effluent discharge and thus did not transfer any waterborne pollution to their receptors during these periods. Copyright © 2018 Elsevier Ltd. All rights reserved.

LCA of contaminated site remediation - integration of site-specific impact assessment of local toxic impacts

DEFF Research Database (Denmark)

Lemming, Gitte; Hauschild, Michael Zwicky; Chambon, Julie Claire Claudia

2011-01-01

impacts have typically been assessed using site-generic characterization models representing a continental scale and excluding the groundwater compartment. Soil contaminants have therefore generally been assigned as emissions to surface soil or surface water compartments. However, such site-generic...... assessments poorly reflect the fate of frequent soil contaminants such as chloroethenes as they exclude the groundwater compartment and assume that the main part escapes to the atmosphere. Another important limitation of the generic impact assessment models is that they do not include the formation......The environmental impacts from remediation can be divided into primary and secondary impacts. Primary impacts cover the local impacts associated with the on-site contamination, whereas the secondary impacts are impacts on the local, regional and global scale generated by the remediation activities...

Lessons learned from the preliminary performance assessment exercise for the Vienne site strategies for investigating the granodiorite confinement capability

International Nuclear Information System (INIS)

Lebon, P.

1999-01-01

One of the three sites under study by ANDRA is located on the Poitou shoal in the Vienne Department. The granitic basement rock is overlain by a 160 m thick layer of Jurassic sediments containing two seasonally pumped aquifers. The preliminary hydrogeological model of the granitic basement assumed that regional flow is SE-NW, and circulates in the hecto-metric fractures, and that groundwater flow velocity is very low. A preliminary performance assessment exercise focusing on the geological barrier was carried out based on these assumptions and a disposal concept where radwaste is stored in separate granodiorite 'blocks' delimited by the water-bearing fractures. As regards of the granodioritic blocks, the programme goals include analysing of detailed structure, obtaining uncontaminated samples of interstitial ground water in order to determine its physicochemical properties and evaluating transport and retention parameters. (author)

The Future Through the Past: The Use of Analog Sites for Design Criteria and Long Term Performance Assessment of Evapotranspiration Landfill Covers

Energy Technology Data Exchange (ETDEWEB)

Shafer, D. S.; Miller, J. J.; Young, M. H.; Edwards, S. C.; Rawlinson, S. E.

2002-02-26

There is growing support for using evapotranspiration (ET) covers for closure of low-level waste (LLW) and other types of waste disposal sites, particularly in the lower latitude arid regions of the western United States. At the Nevada Test Site (NTS), monolayer ET covers are the baseline technology for closure of LLW and mixed LLW cells. To better predict the long-term performance of monolayer ET covers, as well as to identify design criteria that will potentially improve their performance, the properties of, and processes occurring on, analog sites for ET covers on the NTS are being studied. The project is funded through the Subsurface Contaminants Focus Area of the U.S. Department of Energy. Four analog sites on the NTS have been selected to predict performance of ET covers over a 1,000-year compliance period. Two sites are relatively recently disturbed (within the last 50 years) and have been selected to evaluate processes and changes on ET covers for the early period after active cover maintenance is discontinued. Two other sites, late to mid-Holocene in age, are intended as analogs for the end of the compliance period (1,000 years or more); both surfaces are abandoned alluvial/colluvial deposits. The history of the early post-institutional control analog sites are being evaluated by an archaeologist to help determine when the sites were last disturbed or modified, and the mode of disturbance to help set baseline conditions. Similar to other ''landforms,'' ET covers will evolve over time because of pedogenic, biotic, and climatic processes. Properties of analog sites that could affect ET water balance performance will be evaluated to help understand ET cover performance over time.

An automated radiological survey method for performing site remediation and decommissioning

International Nuclear Information System (INIS)

Handy, R.G.; Bolch, W.E.; Harder, G.F.; Tolaymat, T.M.

1994-01-01

A portable, computer-based method of performing environmental monitoring and assessment for site remediation and decommissioning has been developed. The integrated system has been developed to provide for survey time reductions and real-time data analysis. The technique utilizes a notebook 486 computer with the necessary hardware and software components that makes it possible to be used in an almost unlimited number of environmental monitoring and assessment scenarios. The results from a pilot, open-quotes hide-and-seekclose quotes gamma survey and an actual alpha decontamination survey were elucidated. It was found that a open-quotes hide-and-seekclose quotes survey could come up with timely and accurate conclusions about the position of the source. The use of the automated system in a Th-232 alpha survey resulted in a reduction in the standard time necessary to do a radiological survey. In addition, the ability to analyze the data on-site allowed for identification and location of areas which needed further decontamination. Finally, a discussion on possible future improvements and field conclusions was made

The development and status of performance assessment in radioactive waste disposal

International Nuclear Information System (INIS)

McCombie, C.; Papp, T.; Coplan, S.

1990-01-01

The development of formal performance assessment in radioactive waste disposal has been in progress for around 10-15 years now. The time is particularly opportune for a review of the state-of-the-art because of current changes in the status of repository planning and implementation worldwide. Several major feasibility-type studies have been completed, the first full site-specific safety analyses are being performed for engineered underground disposal facilities for L/ILW, and - for HLW - the die are now being cast by implementers and regulatory determining how the safety analyses for licensing are to be performed and assessed. The article reviews the development of performance assessment and attempts to identify some key issues occupying safety analysts and regulatory reviewers involved in waste disposal today. (author) 7 figs

Preliminary Performance Assessment for Disposal of APT and CLWR/TEF Wastes at SRS

International Nuclear Information System (INIS)

Wilhite, E.L.

1998-01-01

This section provides the descriptive information for understanding the analyses presented in this preliminary performance assessment. This section addresses the approach taken in the PA, provides a general description of the Savannah River Site E-Area low-level waste facility, and discusses the performance criteria used for evaluating performance

SITE: a methodology for assessment of energy facility siting patterns. Regional studies program

International Nuclear Information System (INIS)

Frigerio, N.A.; Habegger, L.J.; King, R.F.; Hoover, L.J.; Clark, N.A.; Cobian, J.M.

1975-08-01

The timely development of the nation's energy production capacity in a manner that minimizes potential adverse local and regional impacts associated with energy facilities requires the use of sophisticated techniques for evaluation of siting alternatives and fuel cycle options. This report is a documentation of the computerized SITE methodology that has been developed for evaluating health, environmental, and socioeconomic impacts related to utilization of alternate sites for energy production within a region of interest. The cost, impact, and attribute vectors, which are generated and displayed on density maps, can be used in a multiparameter overlay process to identify preferable siting areas. The assessment of clustered facilities in energy centers is also possible within the SITE analysis framework. An application of the SITE methodology to Northern Illinois is presented. Also included is a description of the ongoing extension of SITE for the accumulative evaluation of alternative regional energy siting patterns and fuel cycle options. An appendix provides documentation and user information for the SITE computer program

Environmental compliance assessment findings for Weldon Spring Site Remedial Action Program

International Nuclear Information System (INIS)

Sigmon, C.F.; Levine, M.B.

1990-01-01

This report presents the results of an environmental assessment conducted at Weldon Spring Site Remedial Action Project (WSSRAP) in St. Charles County, Missouri, in accordance with the Formerly Utilized Sites Remedial Action Program (FUSRAP) Environmental Compliance Assessment Checklists. The purpose of this assessment was to evaluate the compliance of the site with applicable federal and Missouri environment regulations. Assessments activities included the following: review of site records, reports ,and files; inspection of the WSSRAP storage building, other selected buildings, and the adjacent grounds; and interviews with project personnel. This assessment was conducted on August 28-30, 1989. The assessment covered five management areas as set forth in the Checklist: Hazardous Waste Management, Polychlorinated Biphenyls (PCBs) Management; Air Emissions; Wastewater Discharges and Petroleum Management. No samples were collected. 1 ref., 2 figs., 1 tab

Improved power performance assessment methods

Energy Technology Data Exchange (ETDEWEB)

Frandsen, S; Antoniou, I; Dahlberg, J A [and others

1999-03-01

The uncertainty of presently-used methods for retrospective assessment of the productive capacity of wind farms is unacceptably large. The possibilities of improving the accuracy have been investigated and are reported. A method is presented that includes an extended power curve and site calibration. In addition, blockage effects with respect to reference wind speed measurements are analysed. It is found that significant accuracy improvements are possible by the introduction of more input variables such as turbulence and wind shear, in addition to mean wind speed and air density. Also, the testing of several or all machines in the wind farm - instead of only one or two - may provide a better estimate of the average performance. (au)

Energy Efficiency, Water Efficiency, and Renewable Energy Site Assessment: Seneca Rocks Discovery Center, Seneca Rocks, West Virginia

Energy Technology Data Exchange (ETDEWEB)

Kiatreungwattana, Kosol [National Renewable Energy Lab. (NREL), Golden, CO (United States); Salasovich, James [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kandt, Alicen [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-03-22

As part of ongoing efforts by the U.S. Forest Service to reduce energy use and incorporate renewable energy technologies into its facilities, the Department of Energy's National Renewable Energy Laboratory performed an energy efficiency and renewable energy site assessment of the Seneca Rocks Discovery Center in Seneca Rocks, West Virginia. This report documents the findings of this assessment, and provides site-specific information for the implementation of energy and water conservation measures, and renewable energy measures.

Application of a generic biosphere model for dose assessments to five European sites

International Nuclear Information System (INIS)

Chen, Q; Kowe, R; Mobbs, S F; Proehl, G; Olyslaegers, G; Zeevaert, T; Kanyar, B; Pinedo, P; Simon, I; Bergstroem, U; Hallberg, B; Jones, J A; Oatway, W B; Watson, S J

2006-01-01

The BIOMOSA (BIOsphere MOdels for Safety Assessment of radioactive waste disposal) project was part of the EC fifth framework research programme. The main goal of this project was to improve the scientific basis for the application of biosphere models in the framework of long-term safety studies of radioactive waste disposal facilities and to enhance the confidence in using biosphere models for performance assessments. The study focused on the development and application of a generic biosphere tool BIOGEM (BIOsphere GEneric Model) using the IAEA BIOMASS reference biosphere methodology, and the comparison between BIOGEM and five site-specific biosphere models. The site-specific models and the generic model were applied to five typical locations in Europe, resulting in estimates of the annual effective individual doses to the critical groups and the ranking of the importance of the exposure pathways for each of the sites. Uncertainty in the results was also estimated by means of stochastic calculations based on variation of the site-specific parameter values. This paper describes the generic model and the deterministic and stochastic results obtained when it was applied to the five sites. Details of the site-specific models and the corresponding results are described in two companion papers. This paper also presents a comparison of the results between the generic model and site-specific models. In general, there was an acceptable agreement of the BIOGEM for both the deterministic and stochastic results with the results from the site-specific models

Development of a Risk-Based Probabilistic Performance-Assessment Method for Long-Term Cover Systems - 2nd Edition

International Nuclear Information System (INIS)

HO, CLIFFORD K.; ARNOLD, BILL W.; COCHRAN, JOHN R.; TAIRA, RANDAL Y.

2002-01-01

A probabilistic, risk-based performance-assessment methodology has been developed to assist designers, regulators, and stakeholders in the selection, design, and monitoring of long-term covers for contaminated subsurface sites. This report describes the method, the software tools that were developed, and an example that illustrates the probabilistic performance-assessment method using a repository site in Monticello, Utah. At the Monticello site, a long-term cover system is being used to isolate long-lived uranium mill tailings from the biosphere. Computer models were developed to simulate relevant features, events, and processes that include water flux through the cover, source-term release, vadose-zone transport, saturated-zone transport, gas transport, and exposure pathways. The component models were then integrated into a total-system performance-assessment model, and uncertainty distributions of important input parameters were constructed and sampled in a stochastic Monte Carlo analysis. Multiple realizations were simulated using the integrated model to produce cumulative distribution functions of the performance metrics, which were used to assess cover performance for both present- and long-term future conditions. Performance metrics for this study included the water percolation reaching the uranium mill tailings, radon gas flux at the surface, groundwater concentrations, and dose. Results from uncertainty analyses, sensitivity analyses, and alternative design comparisons are presented for each of the performance metrics. The benefits from this methodology include a quantification of uncertainty, the identification of parameters most important to performance (to prioritize site characterization and monitoring activities), and the ability to compare alternative designs using probabilistic evaluations of performance (for cost savings)

Methodology for assessing performance of waste management systems

International Nuclear Information System (INIS)

Meshkov, N.K.; Herzenberg, C.L.; Camasta, S.F.

1988-01-01

The newly revised draft DOE Order 5820.2, Chapter 3, requires that DOE low-level waste shall be managed on a systematic basis using the most appropriate combination of waste generation reduction, segregation, treatment, and disposal practices so that the radioactive components are contained and the overall cost effectiveness is minimized. This order expects each site to prepare and maintain an overall waste management systems performance assessment supporting the combination of waste management practices used in generation reduction segregation, treatment, packaging, storage, and disposal. A document prepared by EG and G Idaho, Inc. for the Department of Energy called Guidance for Conduct of Waste Management Systems Performance Assessment is specifically intended to provide the approach necessary to meet the systems performance assessment requirement of DOE Order 5820.2, Chapter 3, and other applicable state regulations dealing with LLW (low-level radioactive wastes). Methods and procedures are needed for assessing the performance of a waste management system. This report addresses this need. The purpose of the methodology provided in this report is to select the optimal way to manage particular sets of waste streams from generation to disposal in a safe and cost-effective manner, and thereby assist the DOE LLW mangers in complying with the DOE Order 5820.2, Chapter 3, and the associated guidance document

Probabilistic Radiological Performance Assessment Modeling and Uncertainty

Science.gov (United States)

Tauxe, J.

2004-12-01

A generic probabilistic radiological Performance Assessment (PA) model is presented. The model, built using the GoldSim systems simulation software platform, concerns contaminant transport and dose estimation in support of decision making with uncertainty. Both the U.S. Nuclear Regulatory Commission (NRC) and the U.S. Department of Energy (DOE) require assessments of potential future risk to human receptors of disposal of LLW. Commercially operated LLW disposal facilities are licensed by the NRC (or agreement states), and the DOE operates such facilities for disposal of DOE-generated LLW. The type of PA model presented is probabilistic in nature, and hence reflects the current state of knowledge about the site by using probability distributions to capture what is expected (central tendency or average) and the uncertainty (e.g., standard deviation) associated with input parameters, and propagating through the model to arrive at output distributions that reflect expected performance and the overall uncertainty in the system. Estimates of contaminant release rates, concentrations in environmental media, and resulting doses to human receptors well into the future are made by running the model in Monte Carlo fashion, with each realization representing a possible combination of input parameter values. Statistical summaries of the results can be compared to regulatory performance objectives, and decision makers are better informed of the inherently uncertain aspects of the model which supports their decision-making. While this information may make some regulators uncomfortable, they must realize that uncertainties which were hidden in a deterministic analysis are revealed in a probabilistic analysis, and the chance of making a correct decision is now known rather than hoped for. The model includes many typical features and processes that would be part of a PA, but is entirely fictitious. This does not represent any particular site and is meant to be a generic example. A

Vicinity Property Assessments at Formerly Utilized Sites Remedial Action Program Project Sites in the New York District - 13420

Energy Technology Data Exchange (ETDEWEB)

Ewy, Ann; Hays, David [U.S. Army Corps of Engineers (United States)

2013-07-01

The Formerly Utilized Sites Remedial Action Program (FUSRAP) has addressed sites across the nation for almost 4 decades. Multiple stake holder pressures, multiple regulations, and process changes occur over such long time periods. These result in many challenges to the FUSRAP project teams. Initial FUSRAP work was not performed under Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Records of Decision (ROD). The ROD identifies the remedy decision and ultimately the criteria to be used to release a site. Early FUSRAP projects used DOE Orders or the Uranium Mill Tailings Radiation Control Act (UMTRCA) standards. Under current RODs, regulations may differ, resulting in different cleanup criteria than that used in prior Vicinity Property (VP) remediation. The USACE, in preparation for closeout of Sites, conducts reviews to evaluate whether prior actions were sufficient to meet the cleanup criteria specified in the current ROD. On the basis of these reviews, USACE has conducted additional sampling, determined that prior actions were sufficient, or conducted additional remediation consistent with the selected remedy in the ROD. As the public pressures, regulations, and processes that the FUSRAP encounters continue to change, the program itself continues to evolve. Assessment of VPs at FUSRAP sites is a necessary step in the life cycle of our site management. (authors)

Vicinity Property Assessments at Formerly Utilized Sites Remedial Action Program Project Sites in the New York District - 13420

International Nuclear Information System (INIS)

Ewy, Ann; Hays, David

2013-01-01

The Formerly Utilized Sites Remedial Action Program (FUSRAP) has addressed sites across the nation for almost 4 decades. Multiple stake holder pressures, multiple regulations, and process changes occur over such long time periods. These result in many challenges to the FUSRAP project teams. Initial FUSRAP work was not performed under Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Records of Decision (ROD). The ROD identifies the remedy decision and ultimately the criteria to be used to release a site. Early FUSRAP projects used DOE Orders or the Uranium Mill Tailings Radiation Control Act (UMTRCA) standards. Under current RODs, regulations may differ, resulting in different cleanup criteria than that used in prior Vicinity Property (VP) remediation. The USACE, in preparation for closeout of Sites, conducts reviews to evaluate whether prior actions were sufficient to meet the cleanup criteria specified in the current ROD. On the basis of these reviews, USACE has conducted additional sampling, determined that prior actions were sufficient, or conducted additional remediation consistent with the selected remedy in the ROD. As the public pressures, regulations, and processes that the FUSRAP encounters continue to change, the program itself continues to evolve. Assessment of VPs at FUSRAP sites is a necessary step in the life cycle of our site management. (authors)

Phase II, Title I engineering assessment of radioactive sands and residues, Lowman Site, Lowman Idaho

Energy Technology Data Exchange (ETDEWEB)

1977-12-01

An engineering assessment was performed of the problems resulting from the existence of radioactive uranium sand residues at the Lowman, Idaho, site. Services normally include the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and other radium-contaminated materials, the evaluation of resulting investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas release from the 90,000 tons of sand residues at the Lowman site constitutes the most significant environmental impact, although external gamma radiation is also a factor. The two alternative actions presented are dike construction, fencing, and maintenance (Option I); and consolidation of the piles, addition of a 2-ft-thick stabilization cover, and on-site cleanup (Option II). Both options include remedial action at off-site structures. Cost estimates for the two options are $393,000 and $590,000.

Phase II, Title I engineering assessment of radioactive sands and residues, Lowman Site, Lowman Idaho

International Nuclear Information System (INIS)

1977-12-01

An engineering assessment was performed of the problems resulting from the existence of radioactive uranium sand residues at the Lowman, Idaho, site. Services normally include the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and other radium-contaminated materials, the evaluation of resulting investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas release from the 90,000 tons of sand residues at the Lowman site constitutes the most significant environmental impact, although external gamma radiation is also a factor. The two alternative actions presented are dike construction, fencing, and maintenance (Option I); and consolidation of the piles, addition of a 2-ft-thick stabilization cover, and on-site cleanup (Option II). Both options include remedial action at off-site structures. Cost estimates for the two options are $393,000 and $590,000

Engineering assessment of inactive uranium mill tailings: Maybell Site, Maybell, Colorado

International Nuclear Information System (INIS)

1981-09-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Maybell site in order to revise the October 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Maybell, Colorado. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 2.6 million dry tons of tailings at the Maybell site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The two alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material (Option I), to disposal of the tailings in a nearby open pit mine and decontamination of the tailings site (Option II). Cost estimates for the two options are about $11,700,000 for stabilization in-place and about $22,700,000 for disposal within a distance of 2 mi. Three principal alternatives for the reprocessing of the Maybell tailings were examined: (a) heap leaching; (b) treatment at an existing mill; and (c) reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $125 and $165/lb of U 3 O 8 by heap leach and conventional plant processes, respectively. The spot market price for uranium was $25/lb early in 1981. Therefore, reprocessing the tailings for uranium recovery is not economically attractive at present

Assessment of Public Acceptability in LILW Repository Site Selection Process in Slovenia

International Nuclear Information System (INIS)

Zeleznik, N.; Kralj, M.; Polic, M.; Kos, D.

2006-01-01

Slovenian national agency for radioactive waste management ARAO has after longer period of preparation activities started with the more direct work on the site selection process for low and intermediate level waste (LILW) repository. In November 2004, the official administrative procedure for the siting of the repository started with the First public conference on spatial planning issues carried out by the Ministry of Environment and Spatial Planning together with ARAO. Just after the conference the Program for the preparation of the Detailed plan of national importance for the LILW repository was accepted by the Ministry. ARAO invited in the beginning of December 2004 all local communities in Slovenia (except 3 of them which have already refused to cooperate) to participate and volunteer a site or area in their local community for further investigation. The invitation for the application of local communities provided clear instructions on how to participate in further determination of potentially suitable sites and under what conditions. By the beginning of April 2005 ARAO finished the bidding process with 8 applications of local communities which decided to participate in the further site selection for LILW repository. Due to the financial and other limitations (human resources, spatial planning procedure, etc.) only in maximum three local communities further characterization could be performed. Therefore prefeasibility study of all volunteer local communities was conducted in which besides technical, environmental and spatial availability also public acceptability should be assessed. For assessment of public acceptability the methodology has been prepared which includes objective parameters of local environment (such as demographic data, economy, infrastructure and social issues in relation to the repository) as well as subjective values (attitudes of individual groups - opinion makers, politicians and all residents - to the sitting and construction of LILW

Deep geologic disposal. Lessons learnt from recent performance assessment studies

International Nuclear Information System (INIS)

Pescatore, C.; Andersson, J.

1998-01-01

Performance assessment (PA) studies are part of the decision basis for the siting, operation, and closure of deep repositories of long-lived nuclear wastes. In 1995 the NEA set up the Working Group on Integrated Performance Assessments of Deep Repositories (IPAG) with the goals to analyse existing PA studies, learn about what has been produced to date, and shed light on what could be done in future studies. Ten organisations submitted their most recent PA study for analysis and discussion, including written answers to over 70 questions. Waste management programmes, disposal concepts, geologies, and different types and amounts of waste offered a unique opportunity for exchanging information, assessing progress in PA since 1990, and identifying recent trends. A report was completed whose main lessons are overviewed. (author)

Engineering assessment of inactive uranium mill tailings, Shiprock site, Shiprock, New Mexico

International Nuclear Information System (INIS)

1981-07-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Shiprock site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Shiprock, New Mexico. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 1.5 million dry tons of tailings at the Shiprock site constitutes the most significant environental impact, although windblown tailings and external gamma radiation also are factors. The eight alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II through VIII). Cost estimates for the eight options range from about $13,400,000 for stabilization in place to about $37,900,000 for disposal at a distance of about 16 miles. Three principal alternatives for the reprocessing of the Shiprock tailings were examined: (a) heap leaching; (b) treatment at an existing mill; and (c) reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $230/lb by heap leach and $250/lb by conventional plant processes. The spot market price for uranium was $25/lb early in 1981. Therefore, reprocessing the tailings for uranium recovery is not economically attractive

Environmental assessment of remedial action at the Gunnison Uranium Mill Tailings Site, Gunnison, Colorado

International Nuclear Information System (INIS)

Bachrach, A.; Hoopes, J.; Morycz, D.; Bone, M.; Cox, S.; Jones, D.; Lechel, D.; Meyer, C.; Nelson, M.; Peel, R.; Portillo, R.; Rogers, L.; Taber, B.; Zelle, P.; Rice, G.

1984-12-01

This document assesses and compares the environmental impacts of various alternatives for remedial action at the Gunnison uranium of mill tailings site located 0.5 miles south of Gunnison, Colorado. The site covers 56 acres and contains 35 acres of tailings, 2 of the original mill buildings and a water tower. The Uranium Mill Tailings Radiation Control of Act of 1978 (UMTRCA), Public Law 95-604, authorizes the US Department of Energy to clean up the site to reduce the potential health impacts associated with the residual radioactive materials remaining at the site and at associated [vicinity] properties off the site. The US Environmental Protection Agency promulgated standards for the remedial actions (40 CFR 192). Remedial actions must be performed in accordance with these standards and with the occurrence of the Nuclear Regulatory Commission. Four alternatives have been addressed in this document. The first alternative is to consolidate the tailings and associated contaminated soils into a recontoured pile on the southern portion of the existing site. A radon barrier of silty clay would be constructed over the pile and various erosion control measures would be taken to assure the long-term integrity of the pile. Two other alternatives which involve moving the tailings to new locations are assessed in this document. These alternatives generally involve greater short-term impacts and are more costly but would result in the tailings being stabilized in a location farther from the city of Gunnison. The no action alternative is also assessed

Engineering assessment of inactive uranium mill tailings, Green River Site, Green River, Utah

International Nuclear Information System (INIS)

1981-08-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Green River site in order to revise the December 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Green River, Utah. This evaluation has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative remedial actions. Radon gas released from the 123,000 tons of tailings at the Green River site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors

Summary of the engineering assessment of inactive uranium mill tailings, Spook Site, Converse County, Wyoming

International Nuclear Information System (INIS)

1981-10-01

Ford, Bacon, Davis Utah Inc. has reevaluated the Spook site in order to revise the December 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings 48 mi northeast of Casper, in Converse County, Wyoming. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 187,000 tons of tailings at the Spook site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover materI), to rema densitometers for measuring cross-sectionally averaged mass velocity in steady steam-water flow are presented. The results are interpreted ntation

Radiological risk assessment for radioactive contamination at landfill site

International Nuclear Information System (INIS)

Devgun, J.S.

1990-01-01

A limited-scope preliminary assessment of radiological risk has been conducted for a landfill site where radioactive residues resulting from past uranium ore processing operations are present. Potential radiation doses to an individual under different scenarios have been predicted using the RESRAD computer code. The assessment provides useful input to the remedial action planning for the site that is currently underway. 7 refs., 6 figs., 3 tabs

Assessing the Performance of Natural Resource Systems

Directory of Open Access Journals (Sweden)

Bruce Campbell

2002-01-01

Full Text Available Assessing the performance of management is central to natural resource management, in terms of improving the efficiency of interventions in an adaptive-learning cycle. This is not simple, given that such systems generally have multiple scales of interaction and response; high frequency of nonlinearity, uncertainty, and time lags; multiple stakeholders with contrasting objectives; and a high degree of context specificity. The importance of bounding the problem and preparing a conceptual model of the system is highlighted. We suggest that the capital assets approach to livelihoods may be an appropriate organizing principle for the selection of indicators of system performance. In this approach, five capital assets are recognized: physical, financial, social, natural, and human. A number of principles can be derived for each capital asset; indicators for assessing system performance should cover all of the principles. To cater for multiple stakeholders, participatory selection of indicators is appropriate, although when cross-site comparability is required, some generic indicators are suitable. Because of the high degree of context specificity of natural resource management systems, a typology of landscapes or resource management domains may be useful to allow extrapolation to broader systems. The problems of nonlinearities, uncertainty, and time lags in natural resource management systems suggest that systems modeling is crucial for performance assessment, in terms of deriving "what would have happened anyway" scenarios for comparison to the measured trajectory of systems. Given that a number of indicators are necessary for assessing performance, the question becomes whether these can be combined to give an integrative assessment. We explore five possible approaches: (1 simple additive index, as used for the Human Development Index; (2 derived variables (e.g., principal components as the indices of performance; (3 two-dimensional plots of

Guidance for treatment of variability and uncertainty in ecological risk assessments of contaminated sites

International Nuclear Information System (INIS)

1998-06-01

Uncertainty is a seemingly simple concept that has caused great confusion and conflict in the field of risk assessment. This report offers guidance for the analysis and presentation of variability and uncertainty in ecological risk assessments, an important issue in the remedial investigation and feasibility study processes. This report discusses concepts of probability in terms of variance and uncertainty, describes how these concepts differ in ecological risk assessment from human health risk assessment, and describes probabilistic aspects of specific ecological risk assessment techniques. The report ends with 17 points to consider in performing an uncertainty analysis for an ecological risk assessment of a contaminated site

Assessing reservoir performance risk in CO{sub 2} storage projects

Energy Technology Data Exchange (ETDEWEB)

Bowden, A.R. [URS Corp., San Francisco, CA (United States); Rigg, A. [CRC for Greenhouse Gas Technologies, Canberra (Australia)

2005-07-01

One of the main issues for researchers involved with geological storage of carbon dioxide (CO{sub 2}) has been the development of a proper methodology to assess and compare alternative CO{sub 2} injection projects on the basis of risk. Consideration needs to be given to technical aspects, such as the risk of leakage and the effectiveness of the intended reservoir, as well as less tangible aspects such as the value and safety of geological storage of CO{sub 2}, and potential impacts on the community and environment. The Geological Disposal of Carbon Dioxide (GEODISC), was a research program of the Australian Petroleum Cooperative Research Centre which identified 56 potential environmentally sustainable sites for CO{sub 2} injection (ESSCIs) within Australia. Several studies were carried out, involving detailed evaluation of the suitability of 4 selected sites, including Dongara, Petrel, Gippsland and Carnarvon. The GEODISC program included a risk assessment research module which required a complete and quantified risk assessment of CO{sub 2} injection as a storage option. Primary goals were to assess the risk of leakage, to assess the effectiveness of the intended reservoir, and to assess negative consequences to facilitate comparison of alternative sites. This paper discussed the background and risk assessment model. Key performance indicators (KPIs) were also developed to address the purpose of risk assessment. It was concluded that the RISQUE method is an appropriate approach and that potential injection projects can be measured against six KPIs including containment; effectiveness; self-funding potential; wider community benefits; community safety and community amenity. 6 refs., 3 tabs., 3 figs.

Baseline ecological risk assessment Salmon Site, Lamar County, Mississippi

International Nuclear Information System (INIS)

1995-04-01

The Salmon Site (SS), formerly the Tatum Dome Test Site, located in Mississippi was the site of two nuclear and two gas explosion tests conducted between 1964 and 1970. A consequence of these testing activities is that radionuclides were released into the salt dome, where they are presently contained. During reentry drilling and other site activities, incidental liquid and solid wastes that contained radioactivity were generated, resulting in some soil, ground water and equipment contamination. As part of the remedial investigation effort, a Baseline Ecological Risk Assessment was conducted at the SS. The purpose is to gauge ecological and other environmental impacts attributable to past activities at the former test facility. The results of this facility-specific baseline risk assessment are presented in this document

Baseline ecological risk assessment Salmon Site, Lamar County, Mississippi

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-04-01

The Salmon Site (SS), formerly the Tatum Dome Test Site, located in Mississippi was the site of two nuclear and two gas explosion tests conducted between 1964 and 1970. A consequence of these testing activities is that radionuclides were released into the salt dome, where they are presently contained. During reentry drilling and other site activities, incidental liquid and solid wastes that contained radioactivity were generated, resulting in some soil, ground water and equipment contamination. As part of the remedial investigation effort, a Baseline Ecological Risk Assessment was conducted at the SS. The purpose is to gauge ecological and other environmental impacts attributable to past activities at the former test facility. The results of this facility-specific baseline risk assessment are presented in this document.

Radiological performance assessment for the E-Area Vaults Disposal Facility. Appendices A through M

Energy Technology Data Exchange (ETDEWEB)

Cook, J.R.

1994-04-15

These document contains appendices A-M for the performance assessment. They are A: details of models and assumptions, B: computer codes, C: data tabulation, D: geochemical interactions, E: hydrogeology of the Savannah River Site, F: software QA plans, G: completeness review guide, H: performance assessment peer review panel recommendations, I: suspect soil performance analysis, J: sensitivity/uncertainty analysis, K: vault degradation study, L: description of naval reactor waste disposal, M: porflow input file. (GHH)

Engineering assessment of inactive uranium mill tailings. Vitro site, Salt Lake City, Utah

International Nuclear Information System (INIS)

1981-04-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Vitro site in order to revise the April 1976 assessment of the problems resulting from the existence of radioactive uranium mill tailings at Salt Lake City, Utah. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 1.9 million tons of tailings at the Vitro site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite and off-site decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings to remote disposal sites, and decontamination of the tailings site (Options II through IV). Cost estimates for the four options range from about $36,400,000 for stabilization in-place, to about $91,000,000 for disposal at a distance of about 85 mi. Three principal alternatives for the reprocessing of the Vitro tailings were examined: heap leaching; treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $200/lb by heap leach and $130/lb by conventional plant processes. Spot market price for uranium was $28.00 in November 1980. Therefore, reprocessing the tailings for uranium recovery appears to be economically unattractive at present

The development and status of performance assessment in radioactive waste disposal

International Nuclear Information System (INIS)

McCombie, C.; Papp, T.; Coplan, S.

1990-01-01

The development of formal performance assessment in radioactive waste disposal has been in progress for around 10-15 years now. The time is particularly opportune for a review of the state-of-the-art because of current changes in the status of repository planning and implementation world-wide. Several major feasibility-type studies have been completed, the first full site-specific safety analyses are being performed for engineered underground disposal facilities for L/ILW, and - for HLW - the die are now being cast by implementers and regulators determining how the safety analyses for licensing are to be performed and assessed. This introductory paper reviews the development of performance assessment, including a reiteration of the aims and a recapitulation of the technical progress and achievements to date. The most important purpose, however, is to identify some key issues occupying safety analysts and regulatory reviewers involved in waste disposal today. The objective is to present the generally accepted consensus on the state of the art in performance assessment. 40 refs., 2 figs

A method of risk assessment for a multi-plant site

International Nuclear Information System (INIS)

White, R.F.

1983-06-01

A model is presented which can be used in conjunction with probabilistic risk assessment to estimate whether a site on which there are several plants (reactors or chemical plants containing radioactive materials) meets whatever risk acceptance criteria or numerical risk guidelines are applied at the time of the assessment in relation to various groups of people and for various sources of risk. The application of the multi-plant site model to the direct and inverse methods of risk assessment is described. A method is proposed by which the potential hazard rating associated with a given plant can be quantified so that an appropriate allocation can be made when assessing the risks associated with each of the plants on a site. (author)

Development of exposure scenarios for CERCLA risk assessments at the Savannah River Site

International Nuclear Information System (INIS)

Nix, D.W.; Immel, J.W.; Phifer, M.A.

1992-01-01

A CERCLA Baseline Risk Assessment (BRA) is performed to determine if there are any potential risks to human health and the environment from waste unit at SRS. The SRS has numerous waste units to evaluate in the RFMU and CMS/FS programs and, in order to provide a consistent approach, four standard exposure scenarios were developed for exposure assessments to be used in human health risk assessments. The standard exposure scenarios are divided into two temporal categories: (a) Current Land Use in the BRA, and (b) Future Land Use in the RERA. The Current Land Use scenarios consist of the evaluation of human health risk for Industrial Exposure (of a worker not involved in waste unit characterization or remediation), a Trespasser, a hypothetical current On-site Resident, and an Off-site Resident. The Future Land Use scenario considers exposure to an On-site Resident following termination of institutional control in the absence of any remedial action (No Action Alternative), as well as evaluating potential remedial alternatives against the four scenarios from the BRA. A critical facet in the development of a BRA or RERA is the scoping of exposure scenarios that reflect actual conditions at a waste unit, rather than using factors such as EPA Standard Default Exposure Scenarios (OSWER Directive 9285.6-03) that are based on upper-bound exposures that tend to reflect worst case conditions. The use of site-specific information for developing risk assessment exposure scenarios will result in a more realistic estimate of Reasonable Maximum Exposure for SRS waste units

Development of exposure scenarios for CERCLA risk assessments at the Savannah River Site

Energy Technology Data Exchange (ETDEWEB)

Nix, D.W.; Immel, J.W. [Westinghouse Savannah River Co., Aiken, SC (United States); Phifer, M.A. [Tennessee Univ., Knoxville, TN (United States). Dept. of Civil Engineering

1992-12-31

A CERCLA Baseline Risk Assessment (BRA) is performed to determine if there are any potential risks to human health and the environment from waste unit at SRS. The SRS has numerous waste units to evaluate in the RFMU and CMS/FS programs and, in order to provide a consistent approach, four standard exposure scenarios were developed for exposure assessments to be used in human health risk assessments. The standard exposure scenarios are divided into two temporal categories: (a) Current Land Use in the BRA, and (b) Future Land Use in the RERA. The Current Land Use scenarios consist of the evaluation of human health risk for Industrial Exposure (of a worker not involved in waste unit characterization or remediation), a Trespasser, a hypothetical current On-site Resident, and an Off-site Resident. The Future Land Use scenario considers exposure to an On-site Resident following termination of institutional control in the absence of any remedial action (No Action Alternative), as well as evaluating potential remedial alternatives against the four scenarios from the BRA. A critical facet in the development of a BRA or RERA is the scoping of exposure scenarios that reflect actual conditions at a waste unit, rather than using factors such as EPA Standard Default Exposure Scenarios (OSWER Directive 9285.6-03) that are based on upper-bound exposures that tend to reflect worst case conditions. The use of site-specific information for developing risk assessment exposure scenarios will result in a more realistic estimate of Reasonable Maximum Exposure for SRS waste units.

A Bayesian belief network approach for assessing uncertainty in conceptual site models at contaminated sites

DEFF Research Database (Denmark)

Thomsen, Nanna Isbak; Binning, Philip John; McKnight, Ursula S.

2016-01-01

the most important site-specific features and processes that may affect the contaminant transport behavior at the site. However, the development of a CSM will always be associated with uncertainties due to limited data and lack of understanding of the site conditions. CSM uncertainty is often found...... to be a major source of model error and it should therefore be accounted for when evaluating uncertainties in risk assessments. We present a Bayesian belief network (BBN) approach for constructing CSMs and assessing their uncertainty at contaminated sites. BBNs are graphical probabilistic models...... that are effective for integrating quantitative and qualitative information, and thus can strengthen decisions when empirical data are lacking. The proposed BBN approach facilitates a systematic construction of multiple CSMs, and then determines the belief in each CSM using a variety of data types and/or expert...

Engineering assessment of inactive uranium mill tailings, Gunnison Site, Gunnison, Colorado: summary

International Nuclear Information System (INIS)

1981-09-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Gunnison site in order to revise the November 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Gunnison, Colorado. This evaluation has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the ivnvestigations of site hydrology and meteorology, and the evaluation and costing of alternative remedial actions. Radon gas released from the combined 540,000 dry tons of tailings and the 435,400 tons of contaminated waste at the Gunnison site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The 10 alternative actions presented in this engineering assessment range from stabilization of the site in its present location with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings to disposal sites along with decontamination of the Gunnison site (Options II through X). Cost estimates for the 10 options range from about $8,900,000 for stabilization in-place, to about $14,000,000 for disposal in the North Alkali Creek area at a distance of about 18 mi. Truck haulage would be used to transport the tailings and contaminated materials from the Gunnison site to the selected disposal site. Three principal alternatives for the reprocessing of the Gunnison tailings were examined: heap leaching; treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocesssing. The cost of the uranium recovered would be about $250 and $230/lb of U 3 O 8 by heap leach and conventional plant processes, respectively. The spot market price for uranium was $25/lb early in 1981

Contaminated site risk and uncertainty assessment for impacts on surface and groundwater

DEFF Research Database (Denmark)

Thomsen, Nanna Isbak

available between sites and choosing between the need for further investigation or remediation. This is a question of prioritizing the sites that pose the greatest risk, and it is a matter of making decisions under uncertainty. Both tasks require a structured assessment of the risk posed by the contaminated...... sites. In a conventional risk assessment of a contaminated site, risk is evaluated by assessing whether a concentration guideline is exceeded at a specific point of compliance in the water resource of interest. If the guideline is exceeded, it is concluded that the site poses a risk. However......, a contaminated site may pose a threat to multiple water resources, or multiple contaminated sites may threaten a single water resource. For more advanced risk assessments, it is therefore relevant to develop methods that can handle this challenge. In this thesis, four contributions are made to the field...

SITE-94. Scenario development FEP audit list preparation: methodology and presentation

International Nuclear Information System (INIS)

Stenhouse, M.; Chapman, N.; Sumerling, T.

1993-04-01

This report concerns a study which is part of the SKI performance assessment project SITE-94. SITE-94 is a performance assessment of a hypothetical repository at a real site. The main objective of the project is to determine how site specific data should be assimilated into the performance assessment process and to evaluate how uncertainties inherent in site characterization will influence performance assessment results. Other important elements of SITE-94 are the development of a practical and defensible methodology for defining, constructing and analyzing scenarios, the development of approaches for treatment of uncertainties , evaluation of canister integrity, and the development and application of an appropriate quality assurance plan for performance assessments

Obtaining reasonable assurance on geochemical aspects of performance assessment of deep geologic repositories

International Nuclear Information System (INIS)

Van Luik, A.E.; Serne, R.J.

1986-01-01

Providing reasonable assurance that a deep geologic disposal system will perform as required by regulation involves, in part, the building of confidence by providing a sound scientific basis for the site characterization, engineered system design, and system performance modeling efforts. Geochemistry plays a role in each of these activities. Site characterization must result in a description of the in situ geochemical environment that will support the design of the engineered system and the modeling of the transport of specific radionuclides to the accessible environment. Judging the adequacy of this site characterization effort is a major aspect of providing reasonable assurance. Within site characterization, there are a number of geochemical issues that need to be addressed such as the usefulness of natural analog studies, and assessing the very long-term stability of the site geochemistry, given expected temperature and radiation conditions

Baseline risk assessment for groundwater contamination at the uranium mill tailings site, Gunnison, Colorado

International Nuclear Information System (INIS)

1990-11-01

The Gunnison Baseline Risk Assessment for Groundwater Contamination at the Uranium Mill Tailings Site was performed to determine if long-term use of groundwater from domestic wells near the site has a potential for adverse health effects. The risk assessment was based on the results of sampling domestic wells during 1989--1990. A risk assessment evaluates health risks by comparing the amount of a contaminant taken in by a person with the amount of the contaminant that may be toxic. The Gunnison Risk Assessment used high intake values to estimate the maximum levels a person might be exposed to. The results of the risk assessment are divided into cancer (carcinogenic) risks and non-carcinogenic risks. Five key contaminants were evaluated for adverse health risks: uranium, manganese, lead antimony, and cadmium. Due to the potential health risks and the unavoidable uncertainties associated with limited groundwater and toxicity data, it is prudent public health policy to provide a permanent alternate water supply. Additionally, providing a permanent alternate water supply is cost-effective compared to long-term routine monitoring

F-Tank Farm Performance Assessment Updates through the Special Analysis Process at Savannah River Site - 12169

Energy Technology Data Exchange (ETDEWEB)

Layton, Mark H. [Savannah River Remediation, LLC (United States)

2012-07-01

The F-Area Tank Farm (FTF) is owned by the U.S. Department of Energy and operated by Savannah River Remediation, LLC (SRR), Liquid Waste Operations contractor at DOE's Savannah River Site (SRS). The FTF is in the north-central portion of the SRS and occupies approximately 22 acres within F-Area. The FTF is an active radioactive waste storage facility consisting of 22 carbon steel waste tanks and ancillary equipment such as transfer lines, evaporators and pump tanks. An FTF Performance Assessment (PA) was prepared to support the eventual closure of the FTF underground radioactive waste tanks and ancillary equipment. The PA provides the technical basis and results to be used in subsequent documents to demonstrate compliance with the pertinent requirements identified below for final closure of FTF. The FTank Farm is subject to a state industrial waste water permit and Federal Facility Agreement. Closure documentation will include an F-Tank Farm Closure Plan and tank-specific closure modules utilizing information from the performance assessment. For this reason, the State of South Carolina and the Environmental Protection Agency must be involved in the performance assessment review process. The residual material remaining after tank cleaning is also subject to reclassification prior to closure via a waste determination pursuant to Section 3116 of the Ronald W. Reagan National Defense Authorization Act of Fiscal Year 2005. The projected waste tank inventories in the FTF PA provide reasonably bounding FTF inventory projections while taking into account uncertainties in the effectiveness of future tank cleaning technologies. As waste is removed from the FTF waste tanks, the residual contaminants will be sampled and the remaining residual inventory is characterized. In this manner, tank specific data for the tank inventories at closure will be available to supplement the waste tank inventory projections currently used in the FTF PA. For FTF, the new tank specific data

White paper updating conclusions of 1998 ILAW performance assessment

International Nuclear Information System (INIS)

MANN, F.M.

2000-01-01

The purpose of this document is to provide a comparison of the estimated immobilized low-activity waste (LAW) disposal system performance against established performance objectives using the beat estimates for parameters and models to describe the system. The principal advances in knowledge since the last performance assessment (known as the 1998 ILAW PA [Mann 1998a]) have been in site specific information and data on the waste form performance for BNFL, Inc. relevant glass formulations. The white paper also estimates the maximum release rates for technetium and other key radionuclides and chemicals from the waste form. Finally, this white paper provides limited information on the impact of changes in waste form loading

White paper updating conclusions of 1998 ILAW performance assessment

Energy Technology Data Exchange (ETDEWEB)

MANN, F.M.

2000-05-11

The purpose of this document is to provide a comparison of the estimated immobilized low-activity waste (LAW) disposal system performance against established performance objectives using the beat estimates for parameters and models to describe the system. The principal advances in knowledge since the last performance assessment (known as the 1998 ILAW PA [Mann 1998a]) have been in site specific information and data on the waste form performance for BNFL, Inc. relevant glass formulations. The white paper also estimates the maximum release rates for technetium and other key radionuclides and chemicals from the waste form. Finally, this white paper provides limited information on the impact of changes in waste form loading.

Performance assessment for Nuclear Power Plant Krsko intermediate and low-level rad-waste repository

International Nuclear Information System (INIS)

Jelavic, V.; Skanata, D.; Plecjas, I.

1990-01-01

Performance safety Assessment for NPP Krsko radwaste repository was performed (LLW/ILW). Shallow land and tunnel type concept were analyzed. Because it was based on two unknown referent sites, one for the shallow land concept and the other for the tunnel type, analysis was generic in nature. Scenario selecting process and consequence analysis were performed by using deterministic approach. Results for both concepts of disposal suggests that proposed NPP Krsko radwaste repository reference site and disposal technology will fully meet radiation limits imposed by the Yugoslav regulations and ICRP guidelines. (author)

Flamanville 3 EPR, Safety Assessment and On-site Inspections

International Nuclear Information System (INIS)

Piedagnel, Corinne; Tarallo, Francois; Monnot, Bernard

2011-01-01

As a Technical Support Organisation of the French Safety Authority (ASN), the IRSN carries out the safety assessment of EPR project design and participates in the ASN inspections performed at the construction site and in factories. The design assessment consists in defining the safety functions which should be ensured by civil structures, evaluating the EPR Technical Code for Civil works (ETC-C) in which EdF has defined design criteria and construction rules, and carrying out a detailed assessment of a selection of safety-related structures. Those detailed assessments do not consist of a technical control but of an analysis whose objectives are to ensure that design and demonstrations are robust, in accordance with safety and regulatory rules. Most assessments led IRSN to ask EdF to provide additional justification sometimes involving significant modifications. In the light of those complementary justifications and modifications, IRSN concluded that assessments carried out on design studies were globally satisfactory. The participation of IRSN to the on-site inspections led by ASN is a part of the global control of the compliance of the reactor with its safety objectives. For that purpose IRSN has defined a methodology and an inspection program intended to ASN: based on safety functions associated with civil works (confinement and resistance to aggressions), the corresponding behaviour requirements are identified and linked to a list of main civil works elements. During the inspections, deviations to the project's technical specifications or to the rules of the art were pointed out by IRSN. Those deviations cover various items, such as concrete fabrication, concrete pouring methodology, lack of reinforcement in some structures, unadapted welding procedures of the containment leak-tight steel liner and unsatisfactory treatment of concreting joints. The analysis of those problems has revealed flaws in the organisation of the contractors teams together with an

Assessing Contractor Capabilities for Streamlined Site Investigations

Science.gov (United States)

The purpose of this document is to familiarize and encourage brownfields decision makers to investigate and employ innovative methods for characterizing their sites, to assist brownfields decision makers in assessing contractors' capabilities.

Performance assessment techniques for groundwater recovery and treatment systems

Energy Technology Data Exchange (ETDEWEB)

Kirkpatrick, G.L. [Environmental Resources Management, Inc., Exton, PA (United States)

1993-03-01

Groundwater recovery and treatment (pump and treat systems) continue to be the most commonly selected remedial technology for groundwater restoration and protection programs at hazardous waste sites and RCRA facilities nationwide. Implementing a typical groundwater recovery and treatment system includes the initial assessment of groundwater quality, characterizing aquifer hydrodynamics, recovery system design, system installation, testing, permitting, and operation and maintenance. This paper focuses on methods used to assess the long-term efficiency of a pump and treat system. Regulatory agencies and industry alike are sensitive to the need for accurate assessment of the performance and success of groundwater recovery systems for contaminant plume abatement and aquifer restoration. Several assessment methods are available to measure the long-term performance of a groundwater recovery system. This paper presents six assessment techniques: degree of compliance with regulatory agency agreement (Consent Order of Record of Decision), hydraulic demonstration of system performance, contaminant mass recovery calculation, system design and performance comparison, statistical evaluation of groundwater quality and preferably, integration of the assessment methods. Applying specific recovery system assessment methods depends upon the type, amount, and quality of data available. Use of an integrated approach is encouraged to evaluate the success of a groundwater recovery and treatment system. The methods presented in this paper are for engineers and corporate management to use when discussing the effectiveness of groundwater remediation systems with their environmental consultant. In addition, an independent (third party) system evaluation is recommended to be sure that a recovery system operates efficiently and with minimum expense.

Preliminary site description Laxemar stage 2.1. Feedback for completion of the site investigation including input from safety assessment and repository engineering

International Nuclear Information System (INIS)

2006-09-01

The Laxemar subarea is the focus for the complete site investigations in the Simpevarp area. The south and southwestern parts of the subarea (the so-called 'focused area') have been designated for focused studies during the remainder of the site investigations. This area, some 5.3 square kilometres in size, is characterised on the surface by an arc shaped body of quartz monzodiorite gently dipping to the north, flanked in the north and south by Aevroe granite. The current report documents work conducted during stage 2.1 of the site-descriptive modelling of the Laxemar subarea. The primary objective of the work performed is to provide feedback to the site investigations at Laxemar to ensure that adequate and timely data and information are obtained during the remaining investigation stage. The work has been conducted in cooperation with the site investigation team at Laxemar and representatives from safety assessment and repository engineering. The principal aim of this joint effort has been to safeguard that adequate data are collected that resolve the remaining issues/uncertainties which are of importance for repository layout and long-term safety. The proposed additional works presented in this report should be regarded as recommended additions and/or modifications in relation to the CSI programme published early 2006. The overall conclusion of the discipline-wise review of critical issues is that the CSI programme overall satisfies the demands to resolve the remaining uncertainties. This is interpreted to be partly a result of the close interaction between the site modelling team, site investigation team and the repository engineering teams, which has been in operation since early 2005. In summary, the performed interpretations and modelling have overall confirmed the version 1.2 results. The exception being Hydrogeology where the new Laxemar 2.1 borehole data suggest more favourable conditions in the south and west parts of the focused area compared with the

Design of an environmental site assessment template for open radioactive site contamination : a radioecological risk approach and case study

International Nuclear Information System (INIS)

Nguyen, T.

2004-01-01

To reduce redundancy, cost, and time, while at the same time ultimately increasing the effectiveness of the radioactive risk management process, a logical framework incorporating risk assessments (human cancer and environmental risks) into the environmental site assessment process was designed for radioactive open site contamination. Risk-based corrective action is becoming an increasingly more acceptable approach for the remediation of contaminated sites. In the past, cleanup goals were usually established without any regard to the risk involved, by mandating remediation goals based solely on maximum contamination levels. Now, a multi-stage environmental site assessment template has been developed on a radioecological approach. The template gives a framework for making environmentally sound decisions based on relevant regulations and guidelines. The first stage involves the comparison of the background screening activity level to the regulated activity level, the second stage involves the use of site-specific information to determine the risk involved with the contamination, and the third stage provides a remediation decision matrix based on results from the first two stages. This environmental site assessment template is unique because it incorporates the modified Canadian National Classification System for radioactive contaminated sites and two different types of risk assessments (human cancer risks and the newly designed ecological risk) into the decision making process. The template was used to assess a radiologically contaminated site at the Canadian Forces Base at Suffield (Alberta) as a case study, and it reaffirms the Department of National Defence's action as appropriate. This particular site is a Class 3, has an overall insignificant human cancer risk ( -6 ) and a low environmental risk, and conforms to all regulated guidelines. Currently, it is restricted and should be left as is, provided that the subsurface is not disturbed. (author)

Management Challenges in Developing Performance Assessments and Effectively Communicating Their Results - 13612

Energy Technology Data Exchange (ETDEWEB)

Thomas, Steve; Mahoney, Mark [Savannah River Remediations LLC, Building 705-1C, Savannah River Site, Aiken, SC 29808 (United States)

2013-07-01

The end of the Cold War has left a legacy of approximately 37 million gallons of radioactive waste in the aging waste tanks at the Department of Energy's Savannah River Site (SRS). A robust program is in place to remove waste from these tanks, treat the waste to separate into a relatively small volume of high level waste and a large volume of low-level waste, and to actively dispose of the low-level waste on-site and close the cleaned waste tanks and associated ancillary structures. To support performance-based, risk-informed decision making, performance assessments have been developed for the low-level waste disposal facility and for the SRS Tank Farms. Although these performance assessments share many similar features, the nature of the hazards and associated containments differ. As a management team, we are challenged to effectively communicate both the similarities and differences of these performance assessments, how they should be used to support sound decision making for treatment, disposal and waste tank cleaning decisions, and in defending their respective assumptions to the regulatory community and the public but, equally important, to our own corporate decision makers and operations personnel. Effective development and defense of these performance assessments, and effective interpretation and communication of the results are key to making cost-effective, pragmatic decisions for the safe disposal of the low-level waste and stabilization and operational closure of the cleaned tanks and associated structures. This paper will focus on the importance and challenges in communicating key attributes, conclusions and operational implications within a company. (authors)

Geotechnical site assessment methodology

International Nuclear Information System (INIS)

Tunbridge, L.W.; Richards, L.R.

1985-09-01

The reports comprising this volume concern the research conducted on geotechnical site assessment methodology at the Carwynnen test mine in granites in Cornwall, with particular reference to the effect of structures imposed by discontinuities on the engineering behaviour of rock masses. The topics covered are: in-situ stress measurements using (a) the hydraulic fracturing method, or (b) the US Bureau of Mines deformation probe; scanline discontinuity survey - coding form and instructions, and data; applicability of geostatistical estimation methods to scalar rock properties; comments on in-situ stress at the Carwynnen test mine and the state of stress in the British Isles. (U.K.)

Quantifying and visualizing site performance in clinical trials

OpenAIRE

Eric Yang; Christopher O'Donovan; JodiLyn Phillips; Leone Atkinson; Krishnendu Ghosh; Dimitris K. Agrafiotis

2018-01-01

Background: One of the keys to running a successful clinical trial is the selection of high quality clinical sites, i.e., sites that are able to enroll patients quickly, engage them on an ongoing basis to prevent drop-out, and execute the trial in strict accordance to the clinical protocol. Intuitively, the historical track record of a site is one of the strongest predictors of its future performance; however, issues such as data availability and wide differences in protocol complexity can co...

A Framework for Treating Uncertainty to Facilitate Waste Disposal Decision Making - Application of the Approach to GCD Performance Assessment

International Nuclear Information System (INIS)

Brown, T.J.; Cochran, J.R.; Gallegos, D.P.

1999-01-01

This paper presents an approach for treating uncertainty in the performance assessment process to efficiently address regulatory performance objectives for radioactive waste disposal and discusses the application of the approach at the Greater Confinement Disposal site. In this approach, the performance assessment methodology uses probabilistic risk assessment concepts to guide effective decisions about site characterization activities and provides a path toward reasonable assurance regarding regulatory compliance decisions. Although the approach is particularly amenable to requirements that are probabilistic in nature, the approach is also applicable to deterministic standards such as the dose-based and concentration-based requirements

Prospective safety performance evaluation on construction sites.

Science.gov (United States)

Wu, Xianguo; Liu, Qian; Zhang, Limao; Skibniewski, Miroslaw J; Wang, Yanhong

2015-05-01

This paper presents a systematic Structural Equation Modeling (SEM) based approach for Prospective Safety Performance Evaluation (PSPE) on construction sites, with causal relationships and interactions between enablers and the goals of PSPE taken into account. According to a sample of 450 valid questionnaire surveys from 30 Chinese construction enterprises, a SEM model with 26 items included for PSPE in the context of Chinese construction industry is established and then verified through the goodness-of-fit test. Three typical types of construction enterprises, namely the state-owned enterprise, private enterprise and Sino-foreign joint venture, are selected as samples to measure the level of safety performance given the enterprise scale, ownership and business strategy are different. Results provide a full understanding of safety performance practice in the construction industry, and indicate that the level of overall safety performance situation on working sites is rated at least a level of III (Fair) or above. This phenomenon can be explained that the construction industry has gradually matured with the norms, and construction enterprises should improve the level of safety performance as not to be eliminated from the government-led construction industry. The differences existing in the safety performance practice regarding different construction enterprise categories are compared and analyzed according to evaluation results. This research provides insights into cause-effect relationships among safety performance factors and goals, which, in turn, can facilitate the improvement of high safety performance in the construction industry. Copyright © 2015 Elsevier Ltd. All rights reserved.

SR 97 - Alternative models project. Discrete fracture network modelling for performance assessment of Aberg

International Nuclear Information System (INIS)

Dershowitz, B.; Eiben, T.; Follin, S.; Andersson, Johan

1999-08-01

As part of studies into the siting of a deep repository for nuclear waste, Swedish Nuclear Fuel and Waste Management Company (SKB) has commissioned the Alternative Models Project (AMP). The AMP is a comparison of three alternative modeling approaches for geosphere performance assessment for a single hypothetical site. The hypothetical site, arbitrarily named Aberg is based on parameters from the Aespoe Hard Rock Laboratory in southern Sweden. The Aberg model domain, boundary conditions and canister locations are defined as a common reference case to facilitate comparisons between approaches. This report presents the results of a discrete fracture pathways analysis of the Aberg site, within the context of the SR 97 performance assessment exercise. The Aberg discrete fracture network (DFN) site model is based on consensus Aberg parameters related to the Aespoe HRL site. Discrete fracture pathways are identified from canister locations in a prototype repository design to the surface of the island or to the sea bottom. The discrete fracture pathways analysis presented in this report is used to provide the following parameters for SKB's performance assessment transport codes FARF31 and COMP23: * F-factor: Flow wetted surface normalized with regards to flow rate (yields an appreciation of the contact area available for diffusion and sorption processes) [TL -1 ]. * Travel Time: Advective transport time from a canister location to the environmental discharge [T]. * Canister Flux: Darcy flux (flow rate per unit area) past a representative canister location [LT -1 ]. In addition to the above, the discrete fracture pathways analysis in this report also provides information about: additional pathway parameters such as pathway length, pathway width, transport aperture, reactive surface area and transmissivity, percentage of canister locations with pathways to the surface discharge, spatial pattern of pathways and pathway discharges, visualization of pathways, and statistical

SR 97 - Alternative models project. Discrete fracture network modelling for performance assessment of Aberg

Energy Technology Data Exchange (ETDEWEB)

Dershowitz, B.; Eiben, T. [Golder Associates Inc., Seattle (United States); Follin, S.; Andersson, Johan [Golder Grundteknik KB, Stockholm (Sweden)

1999-08-01

As part of studies into the siting of a deep repository for nuclear waste, Swedish Nuclear Fuel and Waste Management Company (SKB) has commissioned the Alternative Models Project (AMP). The AMP is a comparison of three alternative modeling approaches for geosphere performance assessment for a single hypothetical site. The hypothetical site, arbitrarily named Aberg is based on parameters from the Aespoe Hard Rock Laboratory in southern Sweden. The Aberg model domain, boundary conditions and canister locations are defined as a common reference case to facilitate comparisons between approaches. This report presents the results of a discrete fracture pathways analysis of the Aberg site, within the context of the SR 97 performance assessment exercise. The Aberg discrete fracture network (DFN) site model is based on consensus Aberg parameters related to the Aespoe HRL site. Discrete fracture pathways are identified from canister locations in a prototype repository design to the surface of the island or to the sea bottom. The discrete fracture pathways analysis presented in this report is used to provide the following parameters for SKB's performance assessment transport codes FARF31 and COMP23: * F-factor: Flow wetted surface normalized with regards to flow rate (yields an appreciation of the contact area available for diffusion and sorption processes) [TL{sup -1}]. * Travel Time: Advective transport time from a canister location to the environmental discharge [T]. * Canister Flux: Darcy flux (flow rate per unit area) past a representative canister location [LT{sup -1}]. In addition to the above, the discrete fracture pathways analysis in this report also provides information about: additional pathway parameters such as pathway length, pathway width, transport aperture, reactive surface area and transmissivity, percentage of canister locations with pathways to the surface discharge, spatial pattern of pathways and pathway discharges, visualization of pathways, and

Summary of the engineering assessment of inactive uranium mill tailings, Tuba City site, Tuba City, Arizona

International Nuclear Information System (INIS)

1981-09-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Tuba City site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Tuba City, Arizona. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 0.8 million tons of tailings at the Tuba City site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material (Option I), to rema densitometers for measuring cross-sectionally averaged mass velocity in steady steam-water flow are presented. The results are interpreted ntation

Fuel and canister process report for the safety assessment SR-Site

International Nuclear Information System (INIS)

Werme, Lars; Lilja, Christina

2010-12-01

This report documents fuel and canister processes identified as relevant to the long-term safety of a KBS-3 repository. It forms an important part of the reporting of the safety assessment SR-Site. The detailed assessment methodology, including the role of the process reports in the assessment, is described in the SR-Site Main report /SKB 2011/

Fuel and canister process report for the safety assessment SR-Site

Energy Technology Data Exchange (ETDEWEB)

Werme, Lars; Lilja, Christina (eds.)

2010-12-15

This report documents fuel and canister processes identified as relevant to the long-term safety of a KBS-3 repository. It forms an important part of the reporting of the safety assessment SR-Site. The detailed assessment methodology, including the role of the process reports in the assessment, is described in the SR-Site Main report /SKB 2011/

Development of exposure scenarios for CERCLA risk assessments at the Savannah River Site (U)

International Nuclear Information System (INIS)

Nix, D.W.; Immel, J.W.; Phifer, M.A.

1992-01-01

Environmental Restoration (ER) activities at the Savannah River Site (SRS) begin with the characterization of inactive hazardous, radioactive and mixed waste disposal areas by a combined Resource Conservation Recovery Act (RCRA) Facility Investigation (RFI)/Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) Remedial Investigation (Rl) followed by evaluation of remedial alternatives in a RCRA Corrective Measures Study (CMS)/CERCLA Feasibility Study (FS). A CERCLA Baseline Risk Assessment (BRA) is performed during the RFVRI characterization to determine if there are any potential risks to human health or the environment from the waste unit. If it is determined that there is need for remedial action, a Risk Evaluation of Remedial Alternatives (RERA) is performed as part of the CMS/FS to provide a basis for selecting a remedy that is protective of human health and the environment. The SRS has numerous waste units to evaluate in the RFI/RI and CMS/FS programs and, in order to provide a consistent approach, four standard exposure scenarios were developed for exposure assessments to be used in human health risk assessments. The standard exposure scenarios are divided into two temporal categories: (a) Current Land Use in the BRA, and (b) Future Land Use in the RERA. The Current Land Use scenarios consist of the evaluation of human health risk for Industrial Exposure (of a worker not involved in waste unit characterization or remediation), a Trespasser, a hypothetical current On-site Resident, and an Off-site Resident. The Future Land Use scenario considers exposure to an On-site Resident following termination of institutional control in the absence of any remedial action (No Action Alternative), as well as evaluating potential remedial alternatives against the four scenarios from the BRA. A critical facet in the development of a BRA or RERA is the seeping of exposure scenarios that reflect actual conditions at a waste unit, rather than using

Quantifying and visualizing site performance in clinical trials

Directory of Open Access Journals (Sweden)

Eric Yang

2018-03-01

Conclusions: The use of operational data from Covance Central Laboratories provides a unique perspective into the performance of clinical sites with respect to many important metrics such as patient enrollment and retention. These metrics can, in turn, be used to guide operational planning and site selection for new clinical trials, thereby accelerating recruitment, improving quality, and reducing cost.

Engineering assessment of inactive uranium mill tailings, Naturita site, Naturita, Colorado. Phase II, Title I

International Nuclear Information System (INIS)

1977-11-01

Ford, Bacon and Davis Utah Inc. has performed an engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Naturita, Colorado. The Phase II, Title I services include the preparation of topographic maps, the performance of core drillings sufficient to determine areas and volumes of tailings, the performance of radiometric measurements to determine the extent of radium contamination, the evaluation of resulting radiation exposures of individuals and nearby populations, the investigation of site hydrology and meteorology, and the costing of alternative corrective actions. Radon gas release from the 704,000 tons of tailings at the Naturita site constitutes the most significant environmental impact although windblown tailings and external gamma radiation are also factors. Ranchers Exploration and Development Company has been licensed by the State of Colorado to reprocess the tailings at a location 3 mi from the present site where they will be stabilized for long-term storage. The remedial action options include remedial action for structures in Naturita and Nucla (Option I) at an estimated cost of $270,000 and remedial action for structures and open land adjacent to the tailings site (Option II) at an estimated cost of $950,000

Low-level radioactive waste performance assessments: Source term modeling

International Nuclear Information System (INIS)

Icenhour, A.S.; Godbee, H.W.; Miller, L.F.

1995-01-01

Low-level radioactive wastes (LLW) generated by government and commercial operations need to be isolated from the environment for at least 300 to 500 yr. Most existing sites for the storage or disposal of LLW employ the shallow-land burial approach. However, the U.S. Department of Energy currently emphasizes the use of engineered systems (e.g., packaging, concrete and metal barriers, and water collection systems). Future commercial LLW disposal sites may include such systems to mitigate radionuclide transport through the biosphere. Performance assessments must be conducted for LUW disposal facilities. These studies include comprehensive evaluations of radionuclide migration from the waste package, through the vadose zone, and within the water table. Atmospheric transport mechanisms are also studied. Figure I illustrates the performance assessment process. Estimates of the release of radionuclides from the waste packages (i.e., source terms) are used for subsequent hydrogeologic calculations required by a performance assessment. Computer models are typically used to describe the complex interactions of water with LLW and to determine the transport of radionuclides. Several commonly used computer programs for evaluating source terms include GWSCREEN, BLT (Breach-Leach-Transport), DUST (Disposal Unit Source Term), BARRIER (Ref. 5), as well as SOURCE1 and SOURCE2 (which are used in this study). The SOURCE1 and SOURCE2 codes were prepared by Rogers and Associates Engineering Corporation for the Oak Ridge National Laboratory (ORNL). SOURCE1 is designed for tumulus-type facilities, and SOURCE2 is tailored for silo, well-in-silo, and trench-type disposal facilities. This paper focuses on the source term for ORNL disposal facilities, and it describes improved computational methods for determining radionuclide transport from waste packages

Engineering assessment of inactive uranium mill tailings: Mexican Hat Site, Mexican Hat, Utah

International Nuclear Information System (INIS)

1981-09-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Mexican Hat site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Mexican Hat, Utah. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 2.2 million tons of tailings at the Mexican Hat site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material to removal of the tailings to remote disposal sites and decontamination of the tailings site. Cost estimates for the four options range from about $15,200,000 for stabilization in place, to about $45,500,000 for disposal at a distance of about 16 mi. Three principal alternatives for the reprocessing of the Mexican Hat tailings were examined: heap leaching; treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $115/lb of U 3 O 8 whether by heap leach or conventional plant processes. The spot market price for uranium was $25/lb early in 1981. Reprocessing the Mexican Hat tailings for uranium recovery is not economically attractive under present conditions

Regulatory compliance for a Yucca Mountain Repository: A performance assessment perspective

International Nuclear Information System (INIS)

Dyer, J.R.; Van Luik, A.E.; Gil, A.V.; Brocoum, S.J.

1997-01-01

The U.S. Department of Energy's Yucca Mountain Site Characterization Project is scheduled to submit a License Application in the year 2002. The License Application is to show compliance with the regulations promulgated by the U.S. Nuclear Regulatory Commission which implement standards promulgated by the U.S. Environmental Protection Agency. These standards are being revised, and it is not certain what their exact nature will be in term of either the performance measure(s) or the time frames that are to be addressed. This paper provides some insights pertaining to this regulatory history, an update on Yucca Mountain performance assessments, and a Yucca Mountain Site Characterization Project perspective on proper standards based on Project experience in performance assessment for its proposed Yucca Mountain Repository system. The Project's performance assessment based perspective on a proper standard applicable to Yucca Mountain may be summarized as follows: a proper standard should be straight forward and understandable; should be consistent with other standards and regulations; and should require a degree of proof that is scientifically supportable in a licensing setting. A proper standard should have several attributes: (1) propose a reasonable risk level as its basis, whatever the quantitative performance measure is chosen to be, (2) state a definite regulatory time frame for showing compliance with quantitative requirements, (3) explicitly recognize that the compliance calculations are not predictions of actual future risks, (4) define the biosphere to which risk needs to be calculated in such a way as to constrain potentially endless speculation about future societies and future human actions, and (5) have as its only quantitative requirement the risk limit (or surrogate performance measure keyed to risk) for the total system

Seismic Hazard Assessment in Site Evaluation for Nuclear Installations: Ground Motion Prediction Equations and Site Response

International Nuclear Information System (INIS)

2016-07-01

The objective of this publication is to provide the state-of-the-art practice and detailed technical elements related to ground motion evaluation by ground motion prediction equations (GMPEs) and site response in the context of seismic hazard assessments as recommended in IAEA Safety Standards Series No. SSG-9, Seismic Hazards in Site Evaluation for Nuclear Installations. The publication includes the basics of GMPEs, ground motion simulation, selection and adjustment of GMPEs, site characterization, and modelling of site response in order to improve seismic hazard assessment. The text aims at delineating the most important aspects of these topics (including current practices, criticalities and open problems) within a coherent framework. In particular, attention has been devoted to filling conceptual gaps. It is written as a reference text for trained users who are responsible for planning preparatory seismic hazard analyses for siting of all nuclear installations and/or providing constraints for anti-seismic design and retrofitting of existing structures

Engineering assessment of inactive uranium mill tailings: Maybell Site, Maybell, Colorado. Summary

International Nuclear Information System (INIS)

1981-09-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Maybell site in order to revise the October 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Maybell, Colorado. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 2.6 million dry tons of tailings at the Maybell site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The two alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material (Option I), to disposal of the tailings in a nearby open pit mine and decontamination of the tailings site (Option II). Cost estimates for the two options are about $11,700,000 for stabilization in-place and about $22,700,000 for disposal within a distance of 2 mi. Three principal alternatives for the reprocessing of the Maybell tailings were examined: (a) heap leaching; (b) treatment at an existing mill; and (c) reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $125 and $165/lb of U 3 O 8 by heap leach and conventional plant processes, respectively. The spot market price for uranium was $25/lb early in 1981. Therefore, reprocessing the tailings for uranium recovery is not economically attractive at present

Safety assessment of multi-unit NPP sites subject to external events

International Nuclear Information System (INIS)

Samaddar, Sujit; Hibino, Kenta; Coman, Ovidiu

2014-01-01

This paper presents a framework for conducting a probabilistic safety assessment of multi-unit sites against external events. The treatment of multiple hazard on a unit, interaction between units, implementation of severe accident measures, human reliability, environmental conditions, metric of risk for both reactor and non-reactor sources, integration of risk and responses and many such important factors need to be addressed within the context of this framework. The framework facilitates the establishment of a comprehensive methodology that can be applied internationally to the peer review of safety assessment of multi-unit sites under the impact of multiple external hazards. In summary, it can be said that the site safety assessment for a multi-unit site will be quite complex and need to start with individual unit risk assessments, these need to be combined considering the interactions between units and their responses, and the fragilities of the installations established considering the combined demands from all interactions. Using newly established risk metric the risk can then be integrated for the overall site. Fig. 2 shows schematically such a proposal. Much work has to done and the IAEA has established a working group that is systematically establishing the structure and process to incorporate the many issues that are a part of a multi-unit site safety assessment. (authors)

Feasibility Study of Economics and Performance of Solar Photovoltaics at the Price Landfill Site in Pleasantville, New Jersey. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

Energy Technology Data Exchange (ETDEWEB)

Salasovich, J.; Geiger, J.; Mosey, G.; Healey, V.

2013-05-01

The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Price Landfill site in Pleasantville, New Jersey, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site. This study did not assess environmental conditions at the site.

Feasibility Study of Economics and Performance of Solar Photovoltaics at the Tower Road Site in Aurora, Colorado. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

Energy Technology Data Exchange (ETDEWEB)

Van Geet, O.; Mosey, G.

2013-03-01

The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Tower Road site in Aurora, Colorado, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site. This study did not assess environmental conditions at the site.

The Effects of Performance-Based Assessment Criteria on Student Performance and Self-Assessment Skills

Science.gov (United States)

Fastre, Greet Mia Jos; van der Klink, Marcel R.; van Merrienboer, Jeroen J. G.

2010-01-01

This study investigated the effect of performance-based versus competence-based assessment criteria on task performance and self-assessment skills among 39 novice secondary vocational education students in the domain of nursing and care. In a performance-based assessment group students are provided with a preset list of performance-based…

Geologic Data Package for 2001 Immobilized Low-Activity Waste Performance Assessment

International Nuclear Information System (INIS)

SP Reidel; DG Horton

1999-01-01

This database is a compilation of existing geologic data from both the existing and new immobilized low-activity waste disposal sites for use in the 2001 Performance Assessment. Data were compiled from both surface and subsurface geologic sources. Large-scale surface geologic maps, previously published, cover the entire 200-East Area and the disposal sites. Subsurface information consists of drilling and geophysical logs from nearby boreholes and stored sediment samples. Numerous published geological reports are available that describe the subsurface geology of the area. Site-specific subsurface data are summarized in tables and profiles in this document. Uncertainty in data is mainly restricted to borehole information. Variations in sampling and drilling techniques present some correlation uncertainties across the sites. A greater degree of uncertainty exists on the new site because of restricted borehole coverage. There is some uncertainty to the location and orientation of elastic dikes across the sites

Risk assessment for the on-site transportation of radioactive wastes for the U.S. Department of Energy Waste Management Programmatic Environmental Impact Statement

International Nuclear Information System (INIS)

Biwer, B.M.; Monette, F.A.; Chen, S.Y.

1996-12-01

This report documents the risk assessment performed for the on-site transportation of radioactive wastes in the US Department of Energy (DOE) Waste Management Programmatic Environmental Impact Statement (WM PEIS). Risks for the routine shipment of wastes and the impacts from potential accidental releases are analyzed for operations at the Hanford Site (Hanford) near Richland, Washington. Like other large DOE sites, hanford conducts waste management operations for all wastes types; consequently, the impacts calculated for Hanford are expected to be greater than those for smaller sites. The risk assessment conducted for on-site transportation is intended to provide an estimate of the magnitude of the potential risk for comparison with off-site transportation risks assessed for the WM PEIS

Systems Analysis, Scenario Construction and Consequence Analysis Definition for SITE-94

Energy Technology Data Exchange (ETDEWEB)

Chapman, N A; Robinson, P [Intera Information Technologies Ltd (United Kingdom); Andersson, Johan; Wingefors, S [Swedish Nuclear Power Inspectorate, Stockholm (Sweden); Skagius, K; Wiborgh, M [Kemakta Konsult AB, Stockholm (Sweden); Wene, C O [Chalmers Inst. of Technology, Goeteborg (Sweden)

1995-06-01

SITE-94 is a performance assessment of a hypothetical repository at a real site. The main objective of the project is to determine how site specific data should be assimilated into the performance assessment process and to evaluate how uncertainties inherent in site characterization will influence performance assessment results. This report uses scenario definition work as a vehicle to introduce the systems approach to performance assessment which has been developed and tested in SITE-94 and which constitutes one of the main advances made during the project. The results of the application of the methodology are presented separately, in the SITE-94 Summary Report. 40 refs, 21 figs, 12 tabs.

Systems Analysis, Scenario Construction and Consequence Analysis Definition for SITE-94

International Nuclear Information System (INIS)

Chapman, N.A.; Robinson, P.; Andersson, Johan; Wingefors, S.; Skagius, K.; Wiborgh, M.; Wene, C.O.

1995-06-01

SITE-94 is a performance assessment of a hypothetical repository at a real site. The main objective of the project is to determine how site specific data should be assimilated into the performance assessment process and to evaluate how uncertainties inherent in site characterization will influence performance assessment results. This report uses scenario definition work as a vehicle to introduce the systems approach to performance assessment which has been developed and tested in SITE-94 and which constitutes one of the main advances made during the project. The results of the application of the methodology are presented separately, in the SITE-94 Summary Report. 40 refs, 21 figs, 12 tabs

The Contribution of Palaeoseismology to Seismic Hazard Assessment in Site Evaluation for Nuclear Installations

International Nuclear Information System (INIS)

2015-06-01

IAEA Safety Standards Series No. SSG-9, Seismic Hazards in Site Evaluation for Nuclear Installations, published in 2010, covers all aspects of site evaluation relating to seismic hazards and recommends the use of prehistoric, historical and instrumental earthquake data in seismic hazard assessments. Prehistoric data on earthquakes cover a much longer period than do historical and instrumental data. However, gathering such data is generally difficult in most regions of the world, owing to an absence of human records. Prehistoric data on earthquakes can be obtained through the use of palaeoseismic techniques. This publication describes the current status and practices of palaeoseismology, in order to support Member States in meeting the recommendations of SSG-9 and in establishing the necessary earthquake related database for seismic hazard assessment and reassessment. At a donors’ meeting of the International Seismic Safety Centre Extrabudgetary Project in January 2011, it was suggested to develop detailed guidelines on seismic hazards. Soon after the meeting, the disastrous Great East Japan Earthquake and Tsunami of 11 March 2011 and the consequent accident at the Fukushima Daiichi nuclear power plant occurred. The importance of palaeoseismology for seismic hazard assessment in site evaluation was highlighted by the lessons learned from the Fukushima Daiichi nuclear power plant accident. However, no methodology for performing investigations using palaeoseismic techniques has so far been available in an IAEA publication. The detailed guidelines and practical tools provided here will be of value to nuclear power plant operating organizations, regulatory bodies, vendors, technical support organizations and researchers in the area of seismic hazard assessment in site evaluation for nuclear installations, and the information will be of importance in support of hazard assessments in the future

Appreciating "Thirdspace": An Alternative Way of Viewing and Valuing Site-Specific Dance Performance

Science.gov (United States)

Munjee, Tara

2014-01-01

Site-specific dance performance involves the presentation of choreography in connection with a site. The context of the site combined with a viewer's personal history, beliefs, and identity impact the reading and appreciation of the performance. Although both stage and site dance performance valuing elicit multiple interpretations of artistic…

Engineering assessment of inactive uranium mill tailings: Mexican Hat site, Mexican Hat, Utah. Summary

International Nuclear Information System (INIS)

1981-09-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Mexican Hat site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Mexican Hat, Utah. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 2.2 million tons of tailings at the Mexican Hat site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material to removal of the tailings to remote disposal sites and decontamination of the tailings site. Cost estimates for the four options range from about $15,200,000 for stabilization in place, to about $45,500,000 for disposal at a distance of about 16 mi. Three principal alternatives for the reprocessing of the Mexican Hat tailings were examined: (a) heap leaching; treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $115/lb of U 3 O 8 whether by heap leach or conventional plant processes. The spot market price for uranium was $25/lb early in 1981. Reprocessing the Mexican Hat tailings for uranium recovery is not economically attractive under present conditions

24 CFR 115.206 - Performance assessments; Performance standards.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Performance assessments; Performance standards. 115.206 Section 115.206 Housing and Urban Development Regulations Relating to Housing... AGENCIES Certification of Substantially Equivalent Agencies § 115.206 Performance assessments; Performance...

2013 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada National Security Site, Nye County, Nevada; Review of the Performance Assessments and Composite Analyses

Energy Technology Data Exchange (ETDEWEB)

Shott, Gregory [NSTec

2014-03-01

The Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site (National Security Technologies, LLC 2007a) requires an annual review to assess the adequacy of the performance assessments (PAs) and composite analyses (CAs), with the results submitted to the U.S. Department of Energy (DOE) Office of Environmental Management. The Disposal Authorization Statements for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) also require that such reviews be made and that secondary or minor unresolved issues be tracked and addressed as part of the maintenance plan (DOE 1999a, 2000). The U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office performed an annual review of the Area 3 and Area 5 RWMS PAs and CAs for fiscal year (FY) 2013. This annual summary report presents data and conclusions from the FY 2013 review, and determines the adequacy of the PAs and CAs. Operational factors (e.g., waste forms and containers, facility design, and waste receipts), closure plans, monitoring results, and research and development (R&D) activities were reviewed to determine the adequacy of the PAs. Likewise, the environmental restoration activities at the Nevada National Security Site (NNSS) relevant to the sources of residual radioactive material that are considered in the CAs, the land-use planning, and the results of the environmental monitoring and R&D activities were reviewed to determine the adequacy of the CAs. Important developments in FY 2013 include the following: • Development of a new Area 5 RWMS closure inventory estimate based on disposals through FY 2013 • Evaluation of new or revised waste streams by special analysis • Development of version 4.115 of the Area 5 RWMS GoldSim PA/CA model The Area 3 RWMS has been in inactive status since July 1, 2006, with the last shipment received in April 2006. The FY 2013 review of operations

ASSESSING AEROBIC NATURAL ATTENUATION OF TRICHLOROETHENE AT FOUR DOE SITES

International Nuclear Information System (INIS)

Koelsch, Michael C.; Starr, Robert C.; Sorenson, Kent S. Jr.

2005-01-01

National Laboratory site using carbon tetrachloride as the conservative tracer under aerobic conditions showed evidence of TCE attenuation with a range of TCE half-lives from 2 to 9.5 years. At Paducah Gaseous Diffusion Plant's Northwest Plume the assessment was performed using Tc-99 as the conservative tracer. TCE appears to have a half-life of about 7 years in the lower portion of the Northwest Plume regional gravel aquifer. Evidence for TCE attenuation at Rocky Flats Environmental Technology Site was identified in two plumes. PCE was used as the conservative tracer in both plumes. TCE appears to be attenuating with a half-life of 0.85 years in the Industrialized Area--Southwest Plume, and with a half-life of 2.4 years in the 903 Pad South Plume. At the Savannah River Site, A/M Area, PCE was used as the conservative tracer in five different horizons. In four of the five horizons, TCE appears to be degrading with a half-life between 4 and 12 years, while no degradation could be quantified in the fifth horizon. If aerobic TCE degradation can be confirmed at these sites, this attenuation mechanism might be important much more often than previously thought, and might make MNA feasible where it was previously not considered

Issues in performance assessments for disposal of US Department of Energy low-level waste

International Nuclear Information System (INIS)

Wood, D.E.; Wilhite, E.L.; Duggan, G.J.

1994-12-01

The US Department of Energy (DOE) and its contractors have long been pioneers in the field of radiological performance assessment (PA). Much effort has been expended in developing technology and acquiring data to facilitate the assessment process. This is reflected in DOE Order 5820.2A, Radioactive Waste Management Chapter III of the Order lists policy and requirements to manage the DOEs low-level waste; performance objectives for low-level waste management are stated to ensure the protection of public health and the environment. A radiological PA is also required to demonstrate compliance with the performance objectives. DOE Order 5820.2A further requires that an Oversight and Peer Review Panel be established to ensure consistency and technical quality around the DOE complex in the development and application of PA models that include site-specific geohydrology and waste composition. The DOE has also established a Performance Assessment Task Team (PATT) to integrate the activities of sites that are preparing PAs. The PATT's purpose is to recommend policy and guidance to DOE on issues that impact PAs so that the approaches taken are as consistent as possible across the DOE complex

Environmental assessments required to support nomination of sites

International Nuclear Information System (INIS)

Mussler, R.M.

1984-01-01

The Nuclear Waste Policy Act of 1982 establishes a schedule for siting the nation's first repository for nuclear waste and spent fuel. The Act assigns the primary responsibility for conducting this siting program to the Department ofEnergy. The provisions of the Act are reviewed, including six legal requirements that must be considered for each environmental assessment, each of which is discussed in detail

Performance assessment for a hypothetical low-level waste disposal facility

International Nuclear Information System (INIS)

Smith, C.S.; Rohe, M.J.; Ritter, P.D.

1997-01-01

Disposing of low-level waste (LLW) is a concern for many states throughout the United States. A common disposal method is below-grade concrete vaults. Performance assessment analyses make predictions of contaminant release, transport, ingestion, inhalation, or other routes of exposure, and the resulting doses for various disposal methods such as the below-grade concrete vaults. Numerous assumptions are required to simplify the processes associated with the disposal facility to make predictions feasible. In general, these assumptions are made conservatively so as to underestimate the performance of the facility. The objective of this report is to describe the methodology used in conducting a performance assessment for a hypothetical waste facility located in the northeastern United States using real data as much as possible. This report consists of the following: (a) a description of the disposal facility and site, (b) methods used to analyze performance of the facility, (c) the results of the analysis, and (d) the conclusions of this study

Performance assessment for a hypothetical low-level waste disposal facility

Energy Technology Data Exchange (ETDEWEB)

Smith, C.S.; Rohe, M.J.; Ritter, P.D. [and others

1997-01-01

Disposing of low-level waste (LLW) is a concern for many states throughout the United States. A common disposal method is below-grade concrete vaults. Performance assessment analyses make predictions of contaminant release, transport, ingestion, inhalation, or other routes of exposure, and the resulting doses for various disposal methods such as the below-grade concrete vaults. Numerous assumptions are required to simplify the processes associated with the disposal facility to make predictions feasible. In general, these assumptions are made conservatively so as to underestimate the performance of the facility. The objective of this report is to describe the methodology used in conducting a performance assessment for a hypothetical waste facility located in the northeastern United States using real data as much as possible. This report consists of the following: (a) a description of the disposal facility and site, (b) methods used to analyze performance of the facility, (c) the results of the analysis, and (d) the conclusions of this study.

Dose assessments in nuclear power plant siting

International Nuclear Information System (INIS)

1988-03-01

This document is mainly intended to provide information on dose estimations and assessments for the purpose of nuclear power plant (NPP) siting. It is not aimed at giving radiation protection guidance, criteria or procedures to be applied during the process of NPP siting nor even to provide recommendations on this subject matter. The document may however be of help for implementing some of the Nuclear Safety Standards (NUSS) documents on siting. The document was prepared before April 26, 1986, when a severe accident at the Unit 4 of Chernobyl NPP in the USSR had occurred. It should be emphasized that this document does not bridge the gap which exists in the NUSS programme as far as radiation protection guidance for the specific case of siting of NPP is concerned. The Agency will continue to work on this subject with the aim to prepare a safety series document on radiation protection requirements for NPP siting. This document could serve as a working document for this purpose. Refs, figs and tabs

Feasibility Study of Economics and Performance of Wind Turbine Generators at the Newport Indiana Chemical Depot Site

Energy Technology Data Exchange (ETDEWEB)

Roberts, Joseph Owen [National Renewable Energy Lab. (NREL), Golden, CO (United States); Mosey, Gail [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2013-11-01

The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Newport Indiana Chemical Depot site in Newport, Indiana, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) was contacted to provide technical assistance for this project. The purpose of this report is to assess the sitefor possible wind turbine electrical generator installation and estimate the cost, performance, and site impacts of different wind energy options. In addition, the report recommends financing options that could assist in the implementation of a wind system at the site.

Siting of a low-level radioactive waste management facility - environmental assessment experiences of the Canadian siting task force

International Nuclear Information System (INIS)

Gorber, D.M.; Story, V.A.

1995-01-01

After public opposition to the plans for a low-level radioactive waste facility at one of two candidate areas at Port Hope, Canada the Environmental Assessment process was postponed, and an independent Siting Process Task Force was set-up to assess the most suitable technologies for LLRW disposal, the areas with the best potential in the province to use these technologies, and the most promising approaches to site selection. The Task Force recommended a five-phased siting process known as the 'Co-operative Siting Process', which was based on the voluntary participation of local communities and a collaborative, joint-planning style of decision making. An independent Siting Task Force was to be established to ensure that the principles of the recommended process was upheld. This siting process is still underway, and problems and successes that have been encountered are summarized in this contribution

Environmental assessment of remedial action at the Mexican Hat uranium mill tailings site, Mexican Hat, Utah

International Nuclear Information System (INIS)

1987-10-01

This document assesses the environmental impacts of the proposed remedial action at the Mexican Hat uranium mill tailings site located on the Navajo Reservation in southern Utah. The site covers 235 acres and contains 69 acres of tailings and several of the original mill structures. Remedial action must be performed in accordance with standards and with the concurrence of the US Nuclear Regulatory Commission and the Navajo Nation. The proposed action is to stabilize the tailings within the present tailings site by consolidating the tailings and associated contaminated soils into a recontoured pile. A radon barrier of compacted earth would be constructed over the pile, and various erosion control measures would be taken to assure the long-term stability of the pile. The no action alternative is also assessed in this document. 240 refs., 12 figs., 20 tabs

Los Alamos low-level waste performance assessment status

International Nuclear Information System (INIS)

Wenzel, W.J.; Purtymun, W.D.; Dewart, J.M.; Rodgers, J.E.

1986-06-01

This report reviews the documented Los Alamos studies done to assess the containment of buried hazardous wastes. Five sections logically present the environmental studies, operational source terms, transport pathways, environmental dosimetry, and computer model development and use. This review gives a general picture of the Los Alamos solid waste disposal and liquid effluent sites and is intended for technical readers with waste management and environmental science backgrounds but without a detailed familiarization with Los Alamos. The review begins with a wide perspective on environmental studies at Los Alamos. Hydrology, geology, and meteorology are described for the site and region. The ongoing Laboratory-wide environmental surveillance and waste management environmental studies are presented. The next section describes the waste disposal sites and summarizes the current source terms for these sites. Hazardous chemical wastes and liquid effluents are also addressed by describing the sites and canyons that are impacted. The review then focuses on the transport pathways addressed mainly in reports by Healy and Formerly Utilized Sites Remedial Action Program. Once the source terms and potential transport pathways are described, the dose assessment methods are addressed. Three major studies, the waste alternatives, Hansen and Rogers, and the Pantex Environmental Impact Statement, contributed to the current Los Alamos dose assessment methodology. Finally, the current Los Alamos groundwater, surface water, and environmental assessment models for these mesa top and canyon sites are described

The Use of Numerical Models in Support of Site Characterization and Performance Assessment Studies of Geological Repositories. Results of an IAEA Coordinated Research Project 2005-2010

International Nuclear Information System (INIS)

2013-10-01

The siting, development and operation of waste disposal facilities, and the related safety issues, have been described in many IAEA publications. The safe management and disposal of radioactive waste from the nuclear fuel cycle remains a necessary condition for future development of nuclear energy. In particular, the disposal of high level waste and spent nuclear fuel in geological repositories, despite having been studied worldwide over the past several decades, still requires full scale demonstration through safe implementation, as planned at the national level in Finland and Sweden by 2020 and 2023, respectively, and in France by 2025. Safety assessment techniques are currently applicable to potential facility location and development through a quite large range of approaches and methodologies. By implementing research activities through coordinated research projects (CRPs), the IAEA enables research institutes in both developing and developed Member States to collaborate on research topics of common interest. In response to requests by several Member States in different networks and platforms dealing with waste disposal, in 2005 a CRP on The Use of Numerical Models in Support of Site Characterization and Performance Assessment Studies of Geological Repositories was proposed and developed to transfer modelling expertise and numerical simulation technology to countries needing them for their national nuclear waste management programmes. All Member States involved in this CRP have acquired the scientific basis for, and expertise in, the site characterization process, including test design, data analysis, model calibration, model validation, predictive modelling, sensitivity analysis and uncertainty propagation analysis. This expertise is documented in this publication, in which numerical modelling is used to address the pertinent issue of site characterization and its impact on safety, using data and information from a potential repository site

Environmental assessment: Reference repository location, Hanford site, Washington

Energy Technology Data Exchange (ETDEWEB)

none,

1986-05-01

In February 1983, the US Department of Energy (DOE) identified a reference repository location at the Hanford Site in Washington as one of the nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high-level radioactive waste. The site is in the Columbia Plateau, which is one of five distinct geohydrologic settings considered for the first repository. To determine their suitability, the Hanford Site and the eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. These evaluations were reported in draft environmental assessments (EAs), which were issued for public review and comment. After considering the comments received on the draft EAs, the DOE prepared the final EAs. On the basis of the evaluations reported in this EA, the DOE has found that the Hanford site is not disqualified under the guidelines. The DOE has also found that it is suitable for site characterization because the evidence does not support a conclusion that the site will not be able to meet each of the qualifying conditions specified in the guidelines. On the basis of these findings, the DOE is nominating the Hanford site as one of five sites suitable for characterization.