IR 05000327/2013004

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IR 05000327-13-004, 05000328-13-004; 07/01/2013 - 09/30/2013; Sequoyah Nuclear Plant, Units 1 and 2; (I.E. Other Activities)
ML13316C220
Person / Time
Site: Sequoyah  Tennessee Valley Authority icon.png
Issue date: 11/12/2013
From: Scott Shaeffer
Reactor Projects Region 2 Branch 6
To: James Shea
Tennessee Valley Authority
References
IR-13-004
Download: ML13316C220 (26)
v • d • e


Text

UNITED STATES vember 12, 2013

SUBJECT:

SEQUOYAH NUCLEAR PLANT - NRC INTEGRATED INSPECTION REPORT 05000327/2013004, 05000328/2013004

Dear Mr. Shea:

On September 30, 2013, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your Sequoyah Nuclear Plant, Units 1 and 2. On October 4, 2013, the NRC inspectors discussed the results of this inspection with Mr. Simmons and other members of your staff. Inspectors documented the results of this inspection in the enclosed inspection report.

NRC inspectors documented one finding of very low safety significance (Green) in this report.

This finding involved a violation of NRC requirements.

Further, inspectors documented a licensee-identified violation which was determined to be of very low safety significance in this report. The NRC is treating this violation as a non-cited violation (NCV) consistent with Section 2.3.2 of the Enforcement Policy.

If you contest the violation or significance of the NCV, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the Nuclear Regulatory Commission, ATTN.: Document Control Desk, Washington DC 20555-0001; with copies to the Regional Administrator, Region II; the Director, Office of Enforcement, United States Nuclear Regulatory Commission, Washington, DC 20555-0001; and the NRC Resident Inspector at the Sequoyah Nuclear Plant.

If you disagree with a cross-cutting aspect assignment in this report, you should provide a response within 30 days of the date of this inspection report, with the basis for your disagreement, to the Regional Administrator, RII, and the NRC Senior Resident Inspector at the Sequoyah Nuclear Plant. In accordance with Title 10 of the Code of Federal Regulations 2.390, Public Inspections, Exemptions, Requests for Withholding, of the NRC's "Rules of Practice," a copy of this letter, its enclosure, and your response (if any) will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of the NRCs Agencywide Documents Access and Management System (ADAMS). ADAMS is accessible from the NRC Website at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).

Sincerely,

/RA/

Scott M. Shaeffer, Chief Reactor Projects Branch 6 Division of Reactor Projects Docket Nos.: 50-327, 50-328 License Nos.: DPR-77, DPR-79

Enclosure:

Inspection Report 05000327/2013004, 05000328/2013004 w/Attachment: Supplemental Information

REGION II==

Docket Nos.: 50-327, 50-328 License Nos.: DPR-77, DPR-79 Report Nos.: 05000327/2013-004, 05000328/2013-004 Licensee: Tennessee Valley Authority (TVA)

Facility: Sequoyah Nuclear Plant, Units 1 and 2 Location: Sequoyah Access Road Soddy-Daisy, TN 37379 Dates: July 1 - September 30, 2013 Inspectors: G .Smith, Senior Resident Inspector W. Deschaine, Resident Inspector P. Braxton, Reactor Inspector (Section 4OA5.1)

Approved by: Scott M. Shaeffer, Chief Reactor Projects Branch 6 Division of Reactor Projects Enclosure

SUMMARY OF FINDINGS

IR 05000327/2013-004, 05000328/2013-004; 7/1-9/30/2013; Sequoyah Nuclear Plant, Units 1 and 2; (i.e. Other Activities)

The report covered a three-month period of inspection by resident inspectors. One non-cited violation and one licensee identified violation were identified. The significance of most findings is indicated by their color (Green, White, Yellow, Red) using Inspection Manual Chapter (IMC)0609, "Significance Determination Process" (SDP). Findings for which the SDP does not apply may be Green or be assigned a severity level after NRC management review. The NRC's program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, "Reactor Oversight Process," Revision 4, dated December 2006.

NRC-Identified

Cornerstone: Mitigating Systems

Green.

The NRC identified a Green non-cited violation (NCV) of 10CFR50 appendix B, Criterion XVI, for the licensees failure to correct a condition adverse to quality (CAQ) per NPG-SPP-22.302, Corrective Action Program Screening and Oversight.

Specifically, in April 2013, an NRC inspector identified that a lack of a vent hole in the 2B RHR pump room flood switch housing was a deficiency previously identified in June 2005 that was not corrected for a period of over seven years. The licensee took immediate corrective action to install the required vent hole. The licensee entered the finding into their corrective action program (CAP) as PER 739142.

This finding was determined to be greater than minor because it was associated with the Design Control attribute of Mitigating Systems cornerstone and adversely affected the cornerstones objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences (i.e., core damage). Specifically, the finding reduced the reliability and capability of the 2B RHR pump room flood switch to perform its safety function as designed. Using IMC 0609.04, Initial Characterization of Findings and IMC 0609 Appendix A, Exhibit 4 - External Events Screening Questions, the finding screened as very low safety significance (Green) because the finding did not involve the total loss of any safety function, identified by the licensee through a PRA, IPEEE, or similar analysis, that contributes to external event initiated core damage accident sequences. The cause of this finding was determined to have a cross-cutting aspect in the Problem Identification and Resolution area, Corrective Action component, and the aspect of taking appropriate corrective actions in a timely manner because corrective actions were not implemented after over seven years from discovery of the CAQ. P.1(d) (Section 4OA5.2).

Licensee-Identified Violations

A violation of very low safety significance which was identified by the licensee was reviewed by the inspectors. Corrective actions taken or planned by the licensee have been entered into the licensees CAP. The violation and corrective action tracking number are listed in Section 4OA7 of this report.

REPORT DETAILS

Summary of Plant Status

Unit 1 operated at or near 100 percent rated thermal power (RTP) for the entire inspection period.

Unit 2 operated at or near 100 percent rated thermal power (RTP) for the entire inspection period.

REACTOR SAFETY

Cornerstones: Initiating Events, Mitigating Systems, and Barrier Integrity

1R01 Adverse Weather Protection

a. Inspection Scope

Impending adverse weather condition (Stage I and II flood warning):

The inspectors evaluated the licensee's response to a stage I and II flood warning during an emergency drill conducted on September 18, 2013. The inspectors reviewed licensee procedure Abnormal Operating Procedure (AOP)-N.03, External Flooding, Revision 48, to assess its effectiveness in limiting the risk of external flooding events and adequately protecting mitigating systems from the effects of flooding various sections of the plant. The inspectors also verified the licensees performance of required flooding actions. The inspectors also evaluated the time compression techniques used to simulate a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period for the establishment of the maximum flood waters. In addition, the inspectors verified the various flood mode equipment/tool boxes were appropriately staged and contained the requisite flooding equipment. This activity constituted one inspection sample.

b. Findings

No findings were identified.

1R04 Equipment Alignment

.1 Partial System Walkdown

a. Inspection Scope

The inspectors performed partial walkdowns of the following three systems to verify the operability of redundant or diverse trains and components when safety equipment was inoperable. The inspectors focused on identification of discrepancies that could impact the function of the system and, therefore, potentially increase risk. The inspectors reviewed applicable operating procedures, walked down control system components, and determined whether selected breakers, valves, and support equipment were in the correct position to support system operation. The inspectors also verified that the licensee had properly identified and resolved equipment alignment problems that could cause initiating events or impact the capability of mitigating systems or barriers and entered them into the corrective action program (CAP). Documents reviewed are listed in the Attachment. The inspectors completed three samples.

  • 1A Safety injection train while 1B OOS for planned maintenance

b. Findings

No findings were identified.

1R05 Fire Protection

.1 Fire Protection Tours

a. Inspection Scope

The inspectors conducted a tour of the five areas important to safety listed below to assess the material condition and operational status of fire protection features. The inspectors evaluated whether: combustibles and ignition sources were controlled in accordance with the licensees administrative procedures; fire detection and suppression equipment was available for use; passive fire barriers were maintained in good material condition; and compensatory measures for out-of-service, degraded, or inoperable fire protection equipment were implemented in accordance with the licensees fire plan.

Documents reviewed are listed in the Attachment. The inspectors completed five samples.

  • Auxiliary building elevation 706
  • Auxiliary Building elevation 714
  • Control Building Elevation 685 (Auxiliary Instrument Rooms)
  • Auxiliary Building Elevation 690 (Corridor)
  • CDWE Building elevations 707.5 & 727.5

b. Findings

No findings were identified.

1R06 Flood Protection Measures

.1 Annual Review of Cables Located in Underground Bunkers/Manholes

a. Inspection Scope

The inspectors conducted a review of licensee inspections of safety-related cables located in underground bunkers/manholes subject to flooding. Specifically, inspectors observed inspections of manhole 52B to determine if water was present and, if found, whether it would affect safety-related system operation. In addition, the inspectors reviewed the licensees CAP to ensure that the licensee was identifying underground cabling issues and that they were properly addressed for resolution. Documents reviewed are listed in the Attachment. The inspectors completed one sample.

b. Findings

No findings were identified.

1R11 Licensed Operator Requalification Program

.1 Quarterly Review

a. Inspection Scope

The inspectors performed one licensed operator requalification program review. The inspectors observed two simulator sessions on August 26, 2013. The training scenarios involved a low power steam generator tube rupture and a steam leak outside containment with two steam generators with failed main steam isolation valves. The inspectors observed crew performance in terms of: communications; ability to take timely and proper actions; prioritizing, interpreting and verifying alarms; correct use and implementation of procedures, including the alarm response procedures; timely control board operation and manipulation, including high risk operator actions; oversight and direction provided by shift manager, including the ability to identify and implement appropriate Technical Specification (TS) action; and, group dynamics involved in crew performance. The inspectors also observed the evaluators critique and reviewed simulator fidelity to verify that it matched actual plant response. Documents reviewed are listed in the Attachment. This activity constituted one inspection sample.

b. Findings

No findings were identified

.2 Quarterly Review of Licensed Operator Performance

a. Inspection Scope

The inspectors observed and assessed licensed operator performance in the main control room during periods of heightened activity or risk. The inspectors reviewed various licensee policies and procedures such as OPDP-1, Conduct of Operations, NPG-SPP-10.0, Plant Operations, and 0-GO-5, Normal Power Operation. The inspectors utilized activities such as post-maintenance testing, surveillance testing, unplanned transients, infrequent plant evolutions, plant startups and shutdowns, reactor power and turbine load changes, and refueling and other outage activities to focus on the following conduct of operations as appropriate:

  • Operator compliance and use of procedures
  • Control board manipulations
  • Communication between crew members
  • Use and interpretation of plant instruments, indications and alarms
  • Use of human error prevention techniques
  • Documentation of activities, including initials and sign-offs in procedures
  • Supervision of activities, including risk and reactivity management
  • Pre-job briefs Specifically, the inspectors observed licensed operator performance during the following activities:
  • Unit 1: Restore rods to all-rods-out
  • Unit 1: Lower turbine load during coast down Documents reviewed are listed in the Attachment. This activity constituted one inspection sample.

b. Findings

No findings were identified

1R12 Maintenance Effectiveness

a. Inspection Scope

The inspectors reviewed the maintenance activities, issues, and systems listed below to verify the effectiveness of the licensees activities in terms of: appropriate work practices; identifying and addressing common cause failures; scoping in accordance with 10 CFR 50.65(b); characterizing reliability issues for performance; trending key parameters for condition monitoring; charging unavailability for performance; classification in accordance with 10 CFR 50.65(a)(1) or (a)(2); appropriateness of performance criteria for SSCs and functions classified as (a)(2); and appropriateness of goals and corrective actions for SSCs and functions classified as (a)(1). Documents reviewed are listed in the Attachment. The inspectors completed two samples.

  • Reviewed placement of ERCW sump pumps into (a)(1) status
  • Reviewed Sequoyah Maintenance Rule Self Assessment conducted May 13 to May 24, 2013

b. Findings

No findings were identified.

1R13 Maintenance Risk Assessments and Emergent Work Control

a. Inspection Scope

The inspectors reviewed the following activities to determine whether appropriate risk assessments were performed prior to removing equipment from service for maintenance. The inspectors evaluated whether risk assessments were performed as required by 10 CFR 50.65(a)(4), and were accurate and complete. When emergent work was performed, the inspectors reviewed whether plant risk was promptly reassessed and managed. The inspectors also evaluated whether the licensees risk assessment tool use and risk categories were in accordance with Standard Programs and Processes Procedure NPG-SPP-07.1, On-Line Work Management, Revision 10, and Instruction 0-TI-DSM-000-007.1, Risk Assessment Guidelines, Revision 9.

Documents reviewed are listed in the Attachment. The inspectors completed five samples.

  • Elevated risk due to emergent work on FCV-63-72
  • Yellow risk for 1B RHR pump maintenance
  • Red grid risk due to Bradley Line being out-of-service (OOS)
  • Review of A train & B train RHR model in EOOS software program

b. Findings

No findings were identified.

1R15 Operability Evaluations

a. Inspection Scope

For the six operability evaluations described in the PERs listed below, the inspectors evaluated the technical adequacy of the evaluations to ensure that TS operability was properly justified and the subject component or system remained available, such that no unrecognized increase in risk occurred. The inspectors compared the operability evaluations to updated final safety analysis report (UFSAR) descriptions to determine if the system or components intended function(s) were adversely impacted. In addition, the inspectors reviewed compensatory measures implemented to determine whether the compensatory measures worked as stated and the measures were adequately controlled. The inspectors also reviewed a sampling of PERs to assess whether the licensee was identifying and correcting any deficiencies associated with operability evaluations. Documents reviewed are listed in the Attachment. The inspectors completed six samples.

  • PER 734974 - DG 7 Day Tank Level Indication
  • PER 724473 - Unit 2 Ice Condenser Intermediate Door Frosting/Icing
  • PER 758465 - UFSAR conflict with Sequoyah vital battery analysis and testing
  • PER 7647742 - 1A-A CCP Room Cooler capability with leaks

b. Findings

Introduction:

An excessive amount of water was noted inside the actuator for 1-FCV-63-72, A train RHR containment sump suction valve, which ultimately rendered the valve inoperable.

Description:

On August 8, 2013 at 0709, the Unit 1 control room reactor operator noted that valve 1-FCV-63-72 showed dual indication on the control board. This valve is the A train RHR suction valve from the containment sump and is normally closed. The valve was verified locally to be in the closed position. No other activities were noted to cause the valve to open. This valve is only stroked during outages (every 18 months) as it is not readily stroked at power due to the system configuration. The licensee determined there was reasonable assurance to consider the valve operable. However, the position indication for the valve was declared inoperable per the post-accident monitoring (PAM) Technical Specification requirement. This was a 30 day Limiting Condition for Operation (LCO). Subsequently on August 14 at 2315, during a routine quarterly IST valve stroke activity, 1-FCV 74-3 failed to stroke in the closed direction from the main control room (MCR). 1-FCV-74-3 is the A train RHR suction valve from the RWST and is normally open. The valve was immediately declared OOS and the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> ECCS tech specification (3.5.2) action statement was entered. Troubleshooting revealed that the actuator of 1-FCV-63-72 contained water and this valve was declared out-of-service. The water intrusion of 1-FCV-63-72 caused shorting of interlock contacts that in turn affected the operability of 1-FCV-74-3. Repairs were made to both valves and the RHR system was returned to operable status on August 17 at 0559. As of the end of the inspection period, the licensee had not completed its formal root cause. The inspectors determined that more inspection was required in order to fully evaluate this issue. Pending additional information from the licensee such that the failure mode of 1-FCV-63-72 can be evaluated, this item was identified as unresolved item (URI)050000327/2013004-01, Water Intrusion into Actuator of Valve 1-FCV-63-72.

1R18 Plant Modifications

.1 Temporary Modifications

a. Inspection Scope

The inspectors reviewed the temporary modification listed below and the associated 10 CFR 50.59 screening, and compared it against the UFSAR and TS to verify whether the modification affected operability or availability of the affected system.

  • SQN-0-2013-012 Provide Temporary Power to Battery Boards I and II from 2-S spare charger Following installation and testing, the inspectors observed indications affected by the modification, discussed them with operators, and verified that the modification was installed properly and its operation did not adversely affect safety system functions.

Documents reviewed are listed in the Attachment. The inspectors completed one sample.

b. Findings

No findings were identified.

1R19 Post-Maintenance Testing

a. Inspection Scope

The inspectors reviewed the post-maintenance tests associated with the eight work orders (WOs) listed below to assess whether procedures and test activities ensured system operability and functional capability. The inspectors reviewed the licensees test procedure to evaluate whether: the procedure adequately tested the safety function(s)that may have been affected by the maintenance activity; the acceptance criteria in the procedure were consistent with information in the applicable licensing basis and/or design basis documents; and the procedure had been properly reviewed and approved.

The inspectors also witnessed the test or reviewed the test data to determine whether test results adequately demonstrated restoration of the affected safety function(s).

Documents reviewed are listed in the Attachment. The inspectors completed eight samples.

  • WO 114966358/114963082 FCV-63-72 repair
  • WO 114198854 - Inspect/clean/adjust/replace, as needed, the belts/sheaves/filters on the Main Control Room AHU A-A

b. Findings

No findings were identified.

1R22 Surveillance Testing

a. Inspection Scope

For the four surveillance tests identified below, the inspectors assessed whether the SSCs involved in these tests satisfied the requirements described in the TS surveillance requirements, the UFSAR, applicable licensee procedures, and whether the tests demonstrated that the SSCs were capable of performing their intended safety functions.

This was accomplished by witnessing testing and/or reviewing the test data. Documents reviewed are listed in the Attachment. The inspectors completed four samples.

In-Service Tests:

  • 0-SI-SXV-003-266.0, ASME Code Valve Testing Routine Surveillance Tests:
  • 1-SI-OPS-082-007.A, Electrical Power System Diesel Generator 1A-A
  • 1-PI-OPS-047-002.0, Steam Inlet Valve Testing
  • 2-SI-OPS-082-024.B, 2B-B D/G 24 Hour Run and Load Rejection Testing

b. Findings

No findings were identified.

Cornerstone: Emergency Preparedness

1EP6 Drill Evaluation

a. Inspection Scope

Resident inspectors evaluated the conduct of routine licensee emergency drill on July 9, 2013, to identify any weaknesses and deficiencies in classification, notification, and protective action recommendation development activities. The inspectors observed emergency response operations in the simulated control room to verify that event classification and notifications were done in accordance with EPIP-1, Emergency Plan Classification Matrix, Revision 50. The inspectors also attended the licensee critique of the drill to compare any inspector observed weakness with those identified by the licensee in order to verify whether the licensee was properly identifying deficiencies.

The inspectors completed one sample.

b. Findings

No findings were identified.

OTHER ACTIVITIES

Cornerstones: Initiating Events, Mitigating Systems, Barrier Integrity, Emergency Preparedness, Public Radiation Safety, Occupational Radiation Safety, and Security

OTHER ACTIVITIES

4OA1 Performance Indicator (PI) Verification

a. Inspection Scope

The inspectors sampled licensee submittals for the Performance Indicators (PI) listed below for the period from July 1, 2012, through June 30, 2013 for both Unit 1 and Unit 2.

Definitions and guidance contained in Nuclear Energy Institute (NEI) 99-02, Regulatory Assessment Indicator Guideline, Revision 6, were used to determine the reporting basis for each data element in order to verify the accuracy of the PI data reported during that period.

Cornerstone: Mitigating Systems

  • Safety System Functional Failures The inspectors reviewed portions of the operations logs and raw PI data developed from monthly operating reports and discussed the methods for compiling and reporting the PIs with engineering personnel. The inspectors also independently calculated selected reported values to verify their accuracy and compared graphical representations from the most recent PI report to the raw data to verify that the data was correctly reflected in the report. Specifically for the Mitigating Systems Performance Index (MSPI), the inspectors reviewed the basis document and derivation reports to verify that the licensee was properly entering the raw data as suggested by NEI 99-02. For Safety System Functional Failures, the inspectors also reviewed LERs issued during the referenced timeframe. Documents reviewed are listed in the Attachment. The inspectors completed six samples.

b. Findings

No findings were identified.

4OA2 Problem Identification and Resolution

.1 Daily Review

a. Inspection Scope

As required by Inspection Procedure 71152, Identification and Resolution of Problems, and in order to help identify repetitive equipment failures or specific human performance issues for follow-up, the inspectors performed a daily screening of items entered into the licensees CAP. This was accomplished by reviewing the description of each new PER and attending daily management review committee meetings.

b. Findings and Observations

No findings were identified.

4OA3 Event Follow-up

.1 (Closed) Licensee Event Report (LER) 05000327/2013-002-00, Loss of Auxiliary Control

Room (ACR) Instrumentation

a. Inspection Scope

On February 26, 2013, it was determined the Sequoyah Unit 1 auxiliary feedwater (AFW) flow indicators in the auxiliary control room (ACR) had been inoperable from February 8, 2013, until February 16, 2013. The Auxiliary Feed Water (AFW) flow indicators in the ACR normally indicate zero. TVA was unable to identify evidence of when exactly they failed. Operators noticed that an Essential Raw Cooling Water indicator failed on February 8, 2013. During troubleshooting on February 15, 2013, it was discovered that two fuses in the circuit cleared. These fuses supply power to instrument loops including power to the AFW flow indicators. When these fuses are blown, power is lost to the flow modifiers that provide indication. The AFW flow indicators are fed from the same power supply that feeds two other instrument loops. A flow modifier that drives a plant computer data point failed resulting in the blown fuses.

The fuses and flow modifier were replaced and the indicators were returned to operable status. Based on the review of the data, it was determined the AFW flow indicators had been out of service longer than allowed by Technical Specification 3.3.3.5. The event was documented in the licensee CAP as PERs 683145, 688013, and 717323.

The inspectors reviewed the LER, PERs and Apparent Cause Evaluation Report to verify that the cause of the event was identified and that corrective actions were appropriate. The inspectors concluded that the licensee's corrective actions were appropriate, including replacing the fuses and flow modifier for the affected circuit and establishing an alarm on the plant computer system should the AFW flow indicator instrument loop lose power. This LER is closed.

b. Findings

A licensee identified violation was identified and is documented in Section 4OA7.

4OA5 Other Activities

.1 (Closed) Unresolved Item (URI) 05000327, 328/2005011-06, Potential for Fire Damage

to Spuriously Open a Containment Sump Isolation Valve

a. Inspection Scope

During an NRC Triennial Fire Protection Inspection (TFPI), as documented in NRC Inspection Report 05000327,328/2005011 (ML053570002), a URI was opened for resolution of issues pertaining to Sequoyah Nuclear Power Plant licensing basis for multiple intra-cable hot shorts. Specifically, the URI was associated with potential fire-induced electrical circuit failures in the containment sump flow isolation valve 1-FCV-63-73 control circuit. Postulated fires in FAA-095 and FAA-070 could result in electrical circuit faults in the control cables and control logic of the isolation valve. These fire-induced faults could cause the valve to spuriously open and drain the refueling water storage tank (RWST) to the containment sump. The issue remained opened pending further NRC review of information related to the plant fire protection licensing/design basis.

The Sequoyah 2008 TFPI (ML082250098) and additional in-office reviews of Sequoyahs fire protection licensing and design basis furthered discussions with the licensee pertaining to the URI. Inspectors conducted additional in-office review of the licensees fire protection program licensing and design basis documents to determine if a performance deficiency existed. Inspectors also reviewed related corrective actions taken by the licensee to determine if they were adequate. The inspectors additional review, including discussions with regional management and NRR technical staff, did not identify a performance deficiency related to the licensing basis and commitments in place at the time the issue was identified. However, inspectors did note that the licensee took corrective actions to address the technical concerns identified in the URI. In 2010, the licensee performed a multiple circuit fault analysis using the guidance in NEI 00-01 Revision 2 and Regulatory Guide 1.189 Revision 2, which resulted in the implementation of plant-wide modifications to resolve multiple circuit failure concerns on Sequoyah Units 1 & 2. Specifically a modification was implemented to resolve the spurious concerns identified in the URI by redesigning and rewiring the flow control valve circuit with a completion date of December 2012.

b. Findings

No findings were identified.

.2 (Closed) (URI) 050000328/2013003-01, Lack of a Vent Hole on the 2B RHR Pump

Room Flood Sensor

a. Inspection Scope

The inspectors opened URI 050000328/2013003-01, Lack of a Vent Hole on the 2B RHR Pump Room Flood Sensor as a result of a flooding inspection in the second quarter 2013. More inspection was required in order to resolve the issue. On April 24, 2013, the inspectors noted that the 2B RHR pump room flood switch lacked a vent hole on the external housing that was prescribed by drawing 47W600-155, Rev. 5. This issue was previously identified as a deficient condition by an NRC inspector in 2005. The licensee subsequently installed the vent hole on July 1. On Sept 6, 2013, the inspectors evaluated testing of the flood switch conducted under WO 114902252 which concluded that the flood switch was able to perform its function despite having no vent hole. This was due to the probe protruding slightly below the external housing and thus had the potential to be activated given a flooding scenario. However, this identified deficient condition did diminish the design capabilities of the switch and was not corrected for over seven years. Only following NRC questioning was the condition ultimately corrected. The inspectors identified the one non-cited violation (NCV) as described below. (URI) 050000328/2013003-01, Lack of a Vent Hole on the 2B RHR Pump Room Flood Sensor is considered closed.

b. Findings

Introduction:

The NRC identified a Green NCV of 10CFR50 appendix B, Criterion XVI, for the licensees failure to correct a condition adverse to quality (CAQ). Specifically, in April 2013, an NRC inspector identified that a lack of a vent hole in the 2B RHR pump room flood switch housing was a deficiency previously identified in June 2005 that was not corrected for a period of over seven years.

Description:

During a flooding walkdown of the 2B RHR pump room on April 24, the inspectors noted that the protective housing that surrounded the room flood sensor, SQN-2-LS-040-0028, had no predrilled vent hole. A visual inspection of several other level sensors located in various other emergency core cooling pump rooms revealed that all sensors had an installed vent hole. A cursory inspection of the housing did not reveal a vent pathway for air. Thus, a rising water level in the room would not necessarily result in a rising level within the protective sensor housing. This non-vented condition could result in an air pocket within the sensors vicinity such that a flooding condition would not be detected by the sensor. A review of the design drawing 47W600-155, detail C155, indicated that a vent hole was required to be installed. Although the sensor protruded slightly (approximately 1/4 inch) below the housing, operability was not ensured. This issue was entered into the CAP as Problem Evaluation Report (PER)739142. The inspectors also noted that this same condition was noted by an NRC inspector on June 30, 2005 and the corrective action from the associated PER 85204 to drill a vent hole under WO #05-777741-000, was not yet completed.

Following questioning by the NRC regarding this deficient condition, the vent hole was installed under the above WO on June 26. On September 6, the inspectors observed and evaluated testing of the flood switch with the vent hole plugged and noted that the switch would still function in a flooding scenario. It was determined that the tip of the probe protruded just below the lip of the housing and this was enough to be actuated by a rising water level. However, the inspectors determined that the vent hole was part of the design of the flood switch and was left uncorrected for over seven years. The inspectors noted that the original PER written in 2005 was designated a C level PER by the licensee. Procedure NPG-SPP-22.302, Corrective Action Program Screening and Oversight, Rev. 0 defines a C level PER as a CAQ that warrants corrective action.

The inspectors determined the failure to install a vent hole was a failure by the licensee to correct a CAQ in a timely manner.

Analysis:

The licensees failure to correct a CAQ per NPG-SPP-22.302, Corrective Action Program Screening and Oversight, Rev. 0, was a performance deficiency. This finding was determined to be greater than minor because it was associated with the Design Control attribute of Mitigating systems cornerstone and adversely affected the cornerstones objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences (i.e., core damage). Specifically, the finding reduced the reliability and capability of the 2B RHR pump room flood switch to perform its safety function as designed. Using IMC 0609.04, Initial Characterization of Findings and IMC 0609 Appendix A, Exhibit 4 - External Events Screening Questions, the finding screened as very low safety significance (Green) because the finding did not involve the total loss of any safety function, identified by the licensee through a PRA, IPEEE, or similar analysis, that contributes to external event initiated core damage accident sequences. The cause of this finding was determined to have a cross-cutting aspect in the Problem Identification and Resolution area, Corrective Action component, and the aspect of taking appropriate corrective actions in a timely manner because corrective actions were not implemented after over seven years from discovery of the CAQ. P.1(d).

Enforcement:

Title 10 of the Code of Federal Regulations Part 50, Appendix B, Criterion XVI, Corrective Action, requires, in part, that Measures shall be established to assure that conditions adverse to quality, such as failures, malfunctions, deficiencies, deviations, defective material and equipment, and non-conformances are promptly identified and corrected. Contrary to the above, following its discovery on June 30, 2005, the licensee failed to correct a condition adverse to quality until June 26, 2013.

Specifically, the licensee failed to correct the 2B RHR pump room flood switch that did not have a vent hole installed in the housing as required by the plants design. On June 26, 2013, the licensee implemented corrective actions to install the vent hole on the switch. Because the finding was of very low safety significance and has been entered into the licensees CAP as PER 739142, this violation is being treated as an NCV, consistent with Section 2.3.2 of the Enforcement Policy: NCV 05000328/2013004-02, Failure to Correct a Condition Adverse to Quality.

.3 Quarterly Resident Inspector Observations of Security Personnel and Activities

a. Inspection Scope

During the inspection period, the inspectors conducted observations of security force personnel and activities to ensure that the activities were consistent with licensee security procedures and regulatory requirements relating to nuclear plant security.

These observations took place during both normal and off-normal plant working hours.

These quarterly resident inspector observations of security force personnel and activities did not constitute any additional inspection samples. Rather, they were considered an integral part of the inspectors normal plant status review and inspection activities.

b. Findings

No findings were identified.

4OA6 Meetings, Including Exit

Exit Meeting Summary

On October 4, 2013, the resident inspectors presented the inspection results to Mr.

Simmons and other members of his staff, who acknowledged the findings. The inspectors asked the licensee whether any of the material examined during the inspection should be considered proprietary. No proprietary information was identified.

4OA7 Licensee-identified Violations

The following violation of very low safety significance (Green) was identified by the licensee and is a violation of NRC requirements which meet the criteria of the NRC Enforcement Policy, for being dispositioned as a NCV.

Unit 1 Technical Specification 3.3.3.5 requires, in part, that the remote shutdown monitoring instrumentation channels shown in Table 3.3-9 shall be operable with readouts displayed external to the control room. With the number of operable remote shutdown monitoring instrumentation channels less than required by Table 3.3-9, restore the inoperable channel(s) to operable status within 7 days, or be in Hot Shutdown within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. One AFW Flow Rate instrumentation channel per steam generator is required per Table 3.3-9. Contrary to the above, on February 26, 2013, the licensee determined that they had two AFW flow indicators (1-FI-3-147C & 1-FI-3-163C)inoperable longer than 7 days. The licensee entered the issue into the corrective action program as PERs 683145, 688013, and 717323. The finding was determined to have very low safety significance (Green) because there was no actual loss of safety system function, and there was no significant increase in the likelihood of a fire.

ATTACHMENT:

SUPPLEMENTAL INFORMATION

KEY POINTS OF CONTACT

Licensee personnel

J. Carlin, Site Vice President
J. Cross, Chemistry Manager
A. Day, Radiation Protection Manager
C. Dieckmann, Manager, Maintenance
J. Johnson, Program Manager Licensing
A. Little, Site Security Manager
T. Marshall, Operations Manager
M. Meade, Flooding Manager
M. McBrearty, Licensing Manager
S. McCamy, Quality Assurance Manager
P. Noe, Director Safety and Licensing
W. Pierce, Site Engineering Director
P. Pratt, Work Control Manager
P. Simmons, Plant Manager
K. Smith, Director of Training

NRC personnel

S. Lingam, Project Manager, Office of Nuclear Reactor Regulation

LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED

Opened

05000327/2013004-01 URI Water Intrusion Into Actuator of Valve 1-

FCV-63-72 (Section 1R15)

Opened and Closed

05000328/2013004-02 NCV Failure to Correct a Condition Adverse to Quality (Section 4OA5.2)

Closed

05000327,328/2005011-06 URI Potential for Fire Damage to Spuriously Open a Containment Sump Isolation Valve (Section 4OA5.1)
05000328/2013003-01 URI Lack of a Vent Hole on the 2B RHR Pump Room Flood Sensor (Section 4OA5.2)

LIST OF DOCUMENTS REVIEWED

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