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On November 21, 2008, the operators perfor … On November 21, 2008, the operators performed Surveillance Test 2BwOSR 3.3.2.8-620A, Unit Two Slave Relay Surveillance (Train A K620 and K633). During the performance of this surveillance test the K620 and the K633 relays failed to energize. Prior to the failure of the relays to energize, the operators declared the 2A AFW system inoperable and entered TS Limiting Condition for Operation (LCO) 3.7.5, Condition A, due to the systems test configuration. The licensee informed the inspectors that the system was considered available for on-line risk purposes due to the fact that the system could be manually realigned to the correct configuration within 41 minutes. The licensee stated that according to the plants probabilistic risk assessment, the AFW system was not needed until 41 minutes following design basis accident. The operators also informed the inspectors that this classification was in accordance with licensees Procedure, WC-AA-101, Online Work Control Process, specifically Attachment 6, Case 4. Case 4 states that the system is available if the equipment could be promptly restored to service. Additionally, in determining whether a system is available, Case 4 also states that restoration actions need not be proceduralized but must be documented and that the assessment may take into account time needed for restoration. Title 10 of CFR Part 50.65 (a)(4), states that before performing maintenance activities (including but not limited to surveillance, post-maintenance testing (PMT) and corrective and preventive maintenance), the licensee shall assess and manage the increase in risk that may result from the proposed maintenance activities. The scope of the assessment may be limited to the SSCs that a risk informed evaluation process has shown to be significant to public health and safety. The definition of SSC Unavailability, for the purposes of availability or reliability calculations in accordance with 10 CFR Part 50.65 (a)(4) requirements, is provided in Appendix B of NUMARC 93-01, Section 11, which is the Nuclear Energy Institutes (NEI) guidance for implementation of 10 CFR Part 50.65 (a)(4) requirements. The NRC endorsed NUMARC 93-01, Section 11 in Regulatory Guide 1.182. In Section 11 of NUMARC 93-01, the unavailability definition is considered for two cases: (1) SSCs tagged out of service, and (2) SSCs not tagged out of service. In the case of 2BwOSR 3.3.2.8-620A, the SSC was out of service for surveillance testing but not be tagged out of service. In accordance with the definition of unavailability in Appendix B, of NUMARC 93-01, SSCs out of service for testing, ...not tagged out, are considered unavailable unless the plant configuration is automatically overridden by a valid starting signal, or the function can be promptly restored either by an operator in the control room or by a dedicated operator stationed locally for that purpose. Restoration actions must be uncomplicated (a single action or a few simple actions) and must not require diagnosis or repair. Credit can be taken only if the (operator) is positioned at the proper location throughout the duration of the test. The inspectors concluded that the intent is to allow licensees to take credit for restoration actions that are virtually certain to be successful during accident conditions. When questioned, the licensee stated that an equipment operator, who was in constant communication with the control room, had been assigned to realign the system if needed. The inspectors asked whether this equipment operator had been assigned any other duties and whether this equipment operator had been stationed locally in the plant at the valves that needed to be realigned. The licensee told the inspectors that the equipment operator was performing other tasks as part of his normal plant tour rounds and therefore was not stationed locally at the valves. The inspectors reviewed 2BwOSR 3.3.2.8-620A and noted that during portions of the surveillance test, contacts for both the K620 and K633 relays were jumpered to measure contact resistance. With these jumpers installed an automatic start of the 2A AFW pump would not occur on a Lo-Lo steam generator water level condition. Additionally, the AFW system discharge test valve 2AF004A would not open automatically on that same signal. This valve is normally open; however, it is closed as part of the test configuration. Following the resistance reading the jumpers are removed. This action restores the ability of the 2AF004A valve to automatically open on a steam generator (Lo-Lo) water level condition, if the K620 and K633 relays are functioning properly. Prior to attempting to energizing the K620 and K633 relays, by use of a test push button, the operators entered TS LCO action statement 3.3.2 Conditions A and J for the AFW system essential service water suction valves, 2AF006A and 2AF017A. These action statements were entered because the test switch (S804) on test panel 1PAJ11, located outside the control room, was placed in TEST, which actuated a circuit blocking function. The SX suction valves would not automatically open on low water level signal coincident with a low AFW pump suction pressure signal. With test switch S804 in TEST, an automatic start of the 2A AFW pump on a steam generator Lo-Lo signal would also be blocked. The inspectors noted that in Section E, Limitation and Actions, of 2BwOSR 3.3.2.8-620A, Step 5 stated that if necessary to emergency exit this test, perform Subsection F.3.0. This section also stated that the verifications might be delayed, but should be performed as soon as practical thereafter. Emergency exit steps contained in Subsection F.3.0 were as following: � Step 3.1 required the operators to verify or remove the jumpers installed in Subsection F.1.0. � Step 3.2 required the operators the release test switch S804 to de-energize Slave Relay K620 and K633. � Step 3.4 directs the operators to remove instrument probes from terminals 1 and 2. � Step 3.5 directs the operators to place test switch S804 to NORMAL, at 2PA11J; and � Step 3.6 required the operator to verify red light 081 is NOT ILLUMINATED indicating Train A Safeguards test cabinet is OUT OF TEST. The inspectors noted that subsequent steps direct the operators to verify or return the 2AF004A, AFW Pump 2A Discharge Control Switch at local control panel to Auto and Open. From further review of Section 11.3.2.7 of NUMARC 93-01, prompt restoration of the out-of-service SSC is the criterion to determine whether the SSC is available or not. In reviewing all of the procedural steps in Section F.3.0, Restoration and Final Conditions, of the Braidwood surveillance procedure, the inspectors noted several operator actions (versus one single action) were needed to return the SSC to service. Additionally, the inspectors did not identify any discussion or considerations of risk management activities, as such stationing maintenance or operation personnel at the locations needed for prompt restoration of the system, documented in the operator logs or in the surveillance test procedure (with the exception of 41 minutes to restore). In addressing this concern, the licensee stated that discussion of risk management activities and considerations were provided by the Unit Supervisor while conducting pre-job brief prior to the start of the surveillance activities. The licensee presented a print of an Excel spreadsheet that listed pre-job brief discussion topics for a number of TS required surveillance procedures. The inspectors reviewed this spreadsheet and noted concerns. For example, under the pre-job discussion topics of 2BwOSR 3.3.2.8-620A, Section F.2.0, instead of Section F.3.0, was listed as the procedure section to refer to if an emergency exit from the procedure is needed. The inspectors raised additional quality control and implementation issues regarding the use of the spreadsheet during pre-job briefs. The licensee documented these concerns in IR 867880. At the conclusion of the inspection period, the inspectors were continuing their evaluation of the licensee processes and controls regarding the management of on-line risk. Therefore, this item will remain open pending further NRC review to determine the adequacy and conformance to licensing and regulatory requirements. (URI 005000456/2008005-02; 05000457/2008005-02)00457/2008005-02)

Discovered date

23:59:59, 31 December 2008 +

Docket

05000456 + and 05000457 +

Event date

23:59:59, 31 December 2008 +

Exelon procedure

WC-AA-101 +

Finding

05000457/FIN-2008005-02 +

Finding integer

2 +

Finding type

URI +

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IR 05000456/2008005 +

Inspector

Richard Skokowski +, G O'Dwyer +, T Hartman +, B Palagi +, R Walton +, D Mcneil +, R Winter +, M Perry +, M Thorpe-Kavanaugh +, Billy Dickson +, Alex Garmoe +, Mel Holmberg +, Raymond Ng +, Garmoeb Dickson +, J Galla + and Matthew Mitchell +

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>.

04:14:10, 22 February 2018 +

NUMARC

NUMARC 93-01 +

Person