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TS 3.9.B.2 requires that when incoming pow … TS 3.9.B.2 requires that when incoming power is not available from both startup and shutdown transformers, continued operation is permissible, provided both diesel generators and associated emergency buses remain operable, all core and containment cooling systems are operable, and reactor power level is reduced to 25% of design. Contrary to the above, on seven occasions between 2005 and August 27, 2014, for an average of 3.6 hours, Entergy conducted test Procedures 3.M.3-1, A5/A6 Buses 4kV Protective Relay Calibration/Functional Test and Annunciator Verification Critical Maintenance, and 3.M.3-29, Shutdown Transformer and 23kV Relay Calibration and Functional Test, that placed the plant in a condition not allowed by TS 3.9.B.2. Specifically, the testing would have prevented emergency buses A5 and A6 from automatically transferring to their backup power supplies. Entergy entered this condition into their CAP as CR 2016- 2735. A Region I SRA conducted a detailed risk evaluation for this issue using IMC 0609, Appendix A, Significance Determination Process for Findings At-Power, issued June 19, 2012. Using the average time from above, along with operator recovery actions, the SRA calculated the change in core damage probability to be <1E-7, which was considered to be of very low safety significance (Green)to be of very low safety significance (Green) +

Discovered date

23:59:59, 31 December 2016 +

Docket

05000293 +

Event date

23:59:59, 31 December 2016 +

Finding integer

6 +

Finding type

Non-cited violation +

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Hours

6.944444e-5 d (0.00167 hours, 9.920635e-6 weeks, 2.283e-6 months) +

Identified by

Licensee-identified +

Inspection Manual Chapter

NRC Inspection Manual 0609/Appendix A, The Significance Determination Process (SDP) for Findings At-Power +

Inspection report

IR 05000293/2016004 +

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>.

15:55:02, 30 May 2018 +

Person