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{{#Regex_clear:During a routine internal a … {{#Regex_clear:During a routine internal audit of the Uranium Recovery 3-inch Extraction System on February 13 at 0930, a Nuclear Criticality Safety (NCS) engineer observed several inconsistencies between the documented limits and controls in the Integrated Safety Analysis summary and those derived in the associated NCS evaluations. These anomalies were non-conservative in nature and included items such as the inside diameters of the columns, column wall thickness, and limits on the number of stainless steel columns in the system. In addition, the most recent NCS evaluation of the system employed a different analytical methodology than earlier evaluations. The evaluation employed the solid angle methodology, which had not been previously utilized to evaluate the 3-inch Extraction System. In past evaluations, the system was modeled using the law of substitution as a 7 x 2 array of 4-inch columns, mirrored in the x and y faces to form an infinite planar array. This change in methodology was incorrect. Based on these uncertainties in the safety basis, the engineer was unable to determine if double contingency was maintained.</br>An evaluation is currently being performed.</br>BWXT is making this 24-hour report in accordance with 10 CFR 70.61, Appendix A, (b)(1) - Any event or condition that results in the facility being in a state that was not analyzed, was improperly analyzed, or is different from that analyzed in the Integrated Safety Analysis, and which results in failure to meet the performance requirements of � 70.61.</br>The operation was immediately shutdown by Nuclear Criticality Safety pending further investigation.</br>The licensee notified the NRC Resident Inspector. }}ee notified the NRC Resident Inspector. }} +
14:30:00, 13 February 2008 +
43,983 +
17:01:00, 13 February 2008 +
14:30:00, 13 February 2008 +
{{#Regex_clear:During a routine internal a … {{#Regex_clear:During a routine internal audit of the Uranium Recovery 3-inch Extraction System on February 13 at 0930, a Nuclear Criticality Safety (NCS) engineer observed several inconsistencies between the documented limits and controls in the Integrated Safety Analysis summary and those derived in the associated NCS evaluations. These anomalies were non-conservative in nature and included items such as the inside diameters of the columns, column wall thickness, and limits on the number of stainless steel columns in the system. In addition, the most recent NCS evaluation of the system employed a different analytical methodology than earlier evaluations. The evaluation employed the solid angle methodology, which had not been previously utilized to evaluate the 3-inch Extraction System. In past evaluations, the system was modeled using the law of substitution as a 7 x 2 array of 4-inch columns, mirrored in the x and y faces to form an infinite planar array. This change in methodology was incorrect. Based on these uncertainties in the safety basis, the engineer was unable to determine if double contingency was maintained.</br>An evaluation is currently being performed.</br>BWXT is making this 24-hour report in accordance with 10 CFR 70.61, Appendix A, (b)(1) - Any event or condition that results in the facility being in a state that was not analyzed, was improperly analyzed, or is different from that analyzed in the Integrated Safety Analysis, and which results in failure to meet the performance requirements of � 70.61.</br>The operation was immediately shutdown by Nuclear Criticality Safety pending further investigation.</br>The licensee notified the NRC Resident Inspector. }}ee notified the NRC Resident Inspector. }} +
Has query"Has query" is a predefined property that represents meta information (in form of a <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Subobject">subobject</a>) about individual queries and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.
00:00:00, 13 February 2008 +
SNM-42 +
Modification date"Modification date" is a predefined property that corresponds to the date of the last modification of a subject and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.
23:30:23, 24 November 2018 +
17:01:00, 13 February 2008 +
0.105 d (2.52 hours, 0.015 weeks, 0.00345 months) +
14:30:00, 13 February 2008 +
24 Hour Report Concerning Improperly Analyzed Condition Related to Integrated Safety Analysis +
URL"URL" is a <a href="/Special:Types/URL" title="Special:Types/URL">type</a> and predefined property provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a> to represent URI/URL values.