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SecPop Version 4: Sector Population Land Fraction and Economic Estimation Program: Users? Guide Model Manual and Verification Report

Weber, scott W.; Bixler, Nathan E.; McFadden, Katherine L.

In 1973 the U.S. Environmental Protection Agency (EPA) developed SecPop to calculate population estimates to support a study on air quality. The Nuclear Regulatory Commission (NRC) adopted this program to support siting reviews for nuclear power plant construction and license applications. Currently SecPop is used to prepare site data input files for offsite consequence calculations with the MELCOR Accident Consequence Code System (MACCS). SecPop enables the use of site-specific population, land use, and economic data for a polar grid defined by the user. Updated versions of SecPop have been released to use U.S. decennial census population data. SECPOP90 was released in 1997 to use 1990 population and economic data. SECPOP2000 was released in 2003 to use 2000 population data and 1997 economic data. This report describes the current code version, SecPop version 4.3, which uses 2010 population data and both 2007 and 2012 economic data. It is also compatible with 2000 census and 2002 economic data. At the time of this writing, the current version of SecPop is 4.3.0, and that version is described herein. This report contains guidance for the installation and use of the code as well as a description of the theory, models, and algorithms involved. This report contains appendices which describe the development of the 2010 census file, 2007 county file, and 2012 county file. Finally, an appendix is included that describes the validation assessments performed.

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TYPE Other Report YEAR 2018
OSTIDOI

Sequoyah SOARCA uncertainty analysis of a STSBO accident

PSAM 2018 - Probabilistic Safety Assessment and Management

Bixler, Nathan E.; Dennis, Matthew L.; Brooks, Dusty M.; Osborn, Douglas M.; Ghosh, S.T.; Hathaway, Alfred

The U.S. Nuclear Regulatory Commission initiated the state-of-the-art reactor consequence analyses (SOARCA) project to develop realistic estimates of the offsite radiological health consequences for potential severe reactor accidents. The SOARCA analysis of an ice condenser containment plant was performed because its relatively low design pressure and reliance on igniters makes it potentially susceptible to early containment failure from hydrogen combustion during a severe accident. The focus was on station blackout accident scenarios where all alternating current power is lost. Accident progression calculations used the MELCOR computer code and offsite consequence analyses were performed with MACCS. The analysis included more than 500 MELCOR and MACCS simulations to account for uncertainty in important accident progression and offsite consequence input parameters. Consequences from severe nuclear power plant accidents modeled in this and previous SOARCA analyses are smaller than calculated in earlier studies. The delayed releases calculated provide more time for emergency response actions. The results show that early containment failure is very unlikely, even without successful use of igniters. However, these results are dependent on the distributions assigned to safety valve failure-to-close parameters, and considerable uncertainty remains on the true distributions for these parameters due to very limited test data. Even for scenarios resulting in early containment failure, the calculated individual latent fatal cancer risks are very small. Early and latent-cancer fatality risks are one focus of this paper. Regression results showing the most influential parameters are also discussed.

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TYPE Conference Poster YEAR 2018
ScopusOSTI

State-of-the-art reactor consequence analyses project: Uncertainty analysis of a potential unmitigated short-term station blackout of the surry nuclear power station

Risk, Reliability and Safety: Innovating Theory and Practice - Proceedings of the 26th European Safety and Reliability Conference, ESREL 2016

Ghosh, S.T.; Ross, Kyle R.; Bixler, Nathan E.; Weber, S.J.; Sallaberry, C.J.; Jones, J.A.

The evaluation of accident phenomena and the potential offsite consequences of severe nuclear reactor accidents has been the subject of considerable research by the U.S. Nuclear Regulatory Commission (NRC) over the last several decades. As a result, capability exists to conduct more detailed, integrated, and realistic analyses of potential severe accidents at nuclear power reactors. Through the application of modern analysis tools and techniques, the State-of-the-Art Reactor Consequence Analyses (SOARCA) project was completed in 2012. This project developed a body of knowledge regarding the realistic outcomes of postulated severe nuclear reactor accidents with best-estimate analyses of selected accident scenarios at the Peach Bottom Atomic Power Station (Peach Bottom), a boiling-water reactor (BWR), and the Surry Power Station (Surry), a pressurized-water reactor (PWR). The SOARCA project continued with an integrated uncertainty analysis (UA) of a potential unmitigated long term station blackout (LTSBO) accident at Peach Bottom completed in 2013. This Peach Bottom UA provided important insights regarding how uncertainties in selected severe accident progression and consequence parameters affect the results of the BWR LTSBO analysis. A Surry integrated UA has just been completed to provide similar insights for a potential PWR short-term station blackout (STSBO).

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TYPE Conference Poster YEAR 2017
ScopusOSTI
Results 26–50 of 109
Results 26–50 of 109