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DOE OSTI · 23047510

Moderation Control Challenges in a Shutdown Facility

Hines, Tom·Wilson, Matthew
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Abstract

On October 27, 2015, an Occurrence Reporting and Processing System (ORPS) Significance Category 1 nuclear criticality safety (NCS) event was discovered at the Paducah Gaseous Diffusion Plant (PGDP) located near Paducah, Kentucky. The NCS violation was a result of the failure to obtain semi-annual moisture samples on sections of large (greater than or equal to 14-inch inside diameter) cascade piping. The event was reported in ORPS EM-PPPOFPDPPGDP- DEAC-2015-0020 under reporting criterion 3C(2) which states, 'A condition in which no documented controls are available to prevent a criticality accident. An accident has not occurred due to other, non-documented barriers or controls.' The purpose of this paper is to present the challenges the site encountered maintaining atmospheric moderation control after the enrichment operation ended, the oversight activities in response to the event and the need to evaluate the changed conditions impact on the Nuclear Criticality Safety Evaluation (NCSE)

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11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIESCRITICALITYGASEOUS DIFFUSION PLANTSHUMIDITYOPERATIONRADIATION ACCIDENTSREACTOR SHUTDOWNSAFETY ANALYSIS

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BibTeXRIS

Hines, Tom, Wilson, Matthew. 2017-07-01. Moderation Control Challenges in a Shutdown Facility. https://www.osti.gov/biblio/23047510

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