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Loss of Automatic Initiation of Auxiliary … Loss of Automatic Initiation of Auxiliary Feedwater Upon Loss of Main Feedwater Technical Specification 3.3.2, Table 1, Engineered Safety Feature Actuation System Instrumentation, Function 6.g, requires, in part, two operable channels of auxiliary feedwater actuation upon trip of all main feedwater pumps in Modes 1 and 2. With one channel inoperable, Technical Specification 3.3.2.J requires, in part, that the affected channel be placed in trip within 6 hours or be in Mode 3 within the following 12 hours. Contrary to the above, on January 20, 2010, the licensee identified that at various times, the actuation logic function for auxiliary feedwater had been inoperable and that the licensee had failed to place the affected channel in trip within 6 hours and was not in Mode 3 within the following 12 hours. Specifically, the actuation logic could not be made up with one main feedwater pump operating and the second main feedwater pump secured and reset. This condition occurred during unit startups and shutdowns. The non-cited violation was documented the licensees corrective action program as Condition Report CR-2010-000638. This finding was more than minor because it was associated with the configuration control attribute of the mitigating systems cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Using IMC 0609.04, Phase 1 - Initial Screening and Characterization of Findings, the issue screened to a Phase 2 significance determination because it involved an actual loss of safety function of a single train for greater than its technical specification allowed outage time. A Phase 2 significance determination was performed using the pre-solved worksheet from the Risk Informed Inspection Notebook for Comanche Peak Nuclear Power Plant. The inspectors noted that this feature was not credited in the plants safety analysis and the auxiliary feedwater safety function was still available. Therefore, using the Phase 2 worksheets, no change in the quantifiable risk was obtained and the finding was determined to be of very low safety significance (Green).e of very low safety significance (Green).

Discovered date

23:59:59, 31 March 2011 +

Docket

05000445 + and 05000446 +

Event date

23:59:59, 31 March 2011 +

Finding integer

4 +

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) + and 1.388889e-4 d (0.00333 hours, 1.984127e-5 weeks, 4.566e-6 months) +

Identified by

Licensee-identified +

Inspection Manual Chapter

NRC Inspection Manual 0609.04 +

Inspection report

IR 05000445/2011002 +

Inspector

D Stearns +, Brian Tindell +, Louis Carson +, John Kramer + and Webb Patricia Walker +

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>.

15:42:06, 30 May 2018 +

Person