IR 05000313/2007009

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IR 05000313-07-009; 05000368-07-009, 10/31/2007 Through 02/20/2008, Arkansas Nuclear One, Units 1 & 2, Special Inspection Report
ML080590142
Person / Time
Site: Arkansas Nuclear  Entergy icon.png
Issue date: 02/27/2008
From: Clark J
NRC/RGN-IV/DRP/RPB-E
To: Mitchell T
Entergy Operations
References
IR-07-009
Download: ML080590142 (43)


Text

UNITED STATES NU CLE AR RE GU LATOR Y C O M M I S S I O N ary 27, 2008

SUBJECT:

ARKANSAS NUCLEAR ONE - NRC SPECIAL INSPECTION REPORT 05000313/2007009 AND 05000368/2007009

Dear Mr. Mitchell:

On February 20, 2008, the U.S. Nuclear Regulatory Commission (NRC) completed a special inspection at your Arkansas Nuclear One, Units 1 and 2, facility. This inspection examined activities associated with a brief fire in an electrical panel resulting in the loss of a division of safety equipment on October 23, 2007. On this occasion a centrifugal charging pump was undergoing 18-month surveillance testing when a fire occurred in the charging pump breaker cubicle which resulted in the loss of a division of safety equipment. In response to the fire a declaration of an Alert was made. The NRC's initial evaluation satisfied the criteria in NRC Management Directive 8.3, NRC Incident Investigation Program, for conducting a special inspection. The basis for initiating this special inspection is further discussed in the inspection charter, which is included in this report as Attachment 2. The determination that the inspection would be conducted was made by the NRC on October 31, 2007, and the inspection started on that date.

The enclosed inspection report documents the inspection findings, which were discussed on November 6, 2007, January 10, 2008 and again on February 20, 2008, with members of your staff. The inspection examined activities conducted under your license as they relate to safety and compliance with the Commission's rules and regulations and with the conditions of your license. The inspectors reviewed selected procedures and records, observed activities, and interviewed personnel.

The report documents three NRC identified and self-revealing findings of very low safety significance (Green). All three of the findings were determined to involve violations of NRC requirements. Because of their very low safety significance and because they were entered into your corrective action program, the NRC is treating these findings as noncited violations (NCVs)

consistent with Section VI.A.1 of the NRC Enforcement Policy. If you contest these NCVs, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the U.S. Nuclear Regulatory Commission, ATTN.: Document Control Desk, Washington DC 20555-0001; with copies to the Regional Administrator, U.S. Nuclear Regulatory Commission Region IV, 611 Ryan Plaza Drive, Suite 400, Arlington, Texas, 76011-4005; the

Entergy Operations, Inc. -2-Director, Office of Enforcement, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001; and the NRC Resident Inspector at the Arkansas Nuclear One, Units 1 and 2, facility.

In accordance with 10 CFR 2.390 of the NRC's Rules of Practice, a copy of this letter, its enclosure, and your response (if any) will be made available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of NRCs document system (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).

Sincerely,

/RA G.Miller for/

Jeff Clark, P.E.

Chief, Project Branch E Division of Reactor Projects Dockets: 50-313; 50-368 License: DPR-51; NPF-6

Enclosure:

NRC Inspection Report 05000313/2007009; 05000368/2007009 w/Attachments Attachment 1: Supplemental Information Attachment 2: Special Inspection Charter Attachment 3: Significance Determination Evaluation

REGION IV==

Docket: 50-313, 50-368 Licenses: DPR-51, NPF-6 Report No.: 05000313/20070009; 05000368/2007009 Licensee: Entergy Operations, Inc.

Facility: Arkansas Nuclear One, Units 1 and 2 Location: Junction of Hwy. 64W and Hwy. 333 South Russellville, Arkansas Dates: October 31, 2007 through February 20, 2008 Inspectors: R. Bywater, Senior Reactor Analyst R. Egli, Reactor Technology Instructor J. Josey, Resident Inspector, Project Branch E, DRP M. Runyan, Senior Reactor Analyst W. Walker, Senior Project Engineer, Project Branch C, DRP Approved By: Jeff Clark, P.E., Chief, Project Branch E Division of Reactor Projects-1- Enclosure

SUMMARY OF FINDINGS

IR 05000313/2007009, 05000368/2007009; 10/31/07 - 02/20/08; Arkansas Nuclear One, Units 1 and 2; Special Inspection in response to a fault in a breaker cubicle which resulted in a brief fire in an electrical panel resulting in the loss of a division of safety equipment on October 23, 2007.

The report covered a 7-day period (October 31 through November 6, 2007) of onsite inspection, with in office review through February 20, 2008, by a special inspection team consisting of one senior project engineer, one resident inspector, and two senior reactor analysts. Three noncited violations were identified. The significance of most findings is indicated by its color (Green,

White, Yellow, or Red) using Inspection Manual Chapter 0609, Significance Determination Process. Findings for which the significance determination process does not apply may be Green or be assigned a severity level after NRCs 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 3, dated July 2000.

Summary of Event The NRC conducted a special inspection to better understand the circumstances surrounding a fault in a breaker cubicle which resulted in a brief fire in an electrical panel resulting in the loss of a division of safety equipment on October 23, 2007. In accordance with NRC Management Directive 8.3, NRC Incident Investigation Program, it was determined that this event involved repetitive failures of systems used to mitigate the effects of an actual event, involved potential adverse generic implications, and had sufficient risk significance to warrant a special inspection.

NRC-Identified and Self-Revealing Findings

Cornerstone: Initiating Events

Green.

A self-revealing noncited violation was identified associated with the licensees failure to comply with Unit 2 Technical Specifications, Section 6.4.1,

Procedures, for the failure to ensure adequate procedures were available for maintenance that was conducted on the Unit 2 motor control centers.

Specifically, the maintenance procedure used by the licensee did not require visual inspections, nor cleaning, and lubrication of the bus to stab contact surface which facilitated degradation of the motor control center bus bars and also allowed this degradation to continue unrecognized. This issue was entered into the licensee's corrective action program as Condition Report ANO-2-2007-1512.

The finding was determined to be more than minor because it affected the protection against external factors attribute of both the Initiating Events and Mitigating Systems cornerstone. Using the Manual Chapter 0609, "Significance Determination Process," Phase 1 worksheets, the inspectors concluded that a Phase 2 evaluation was required.

The inspectors performed a Phase 2 analysis using Appendix A, "Technical Basis For At Power Significance Determination Process," of Manual Chapter 0609,

"Significance Determination Process," and the Phase 2 worksheets for Arkansas Nuclear One. The inspectors determined that the Phase 2 presolved table and worksheets did not contain appropriate target sets to estimate accurately the risk impact of the finding, therefore, a senior reactor analyst performed a Phase 3 analysis. The estimated change in core damage frequency was 8.463E-7/yr.

The estimated change in large early release frequency was 4.842E-8/yr.

Therefore, the significance of the finding was determined to be

Green.

(Section 2.1)

Green.

A self-revealing noncited violation of 10 CFR Part 50, Appendix B,

Criterion XVI, Corrective Actions, was identified associated with the licensees failure to implement adequate corrective actions to prevent recurrence of a significant condition adverse to quality. Specifically, during the Root Cause Evaluation performed for the fire in Motor Control Center 2B-22 in October 2000, the licensee failed to recognize and evaluate previously documented instances where other breakers exhibited degraded connections that were similar, and as such, were precursors to the failure of the breaker in Motor Control Center 2B-22.

Also, the licensee failed to recognize and evaluate these same degraded breaker connection conditions that were discovered during extent of condition inspections and subsequent motor control center maintenance inspections. The licensees failure to identify and evaluate all instances of degraded breaker connections contributed to their failure to adequately identify the cause and implement corrective actions to prevent recurrence of this significant condition adverse to quality. This resulted in a fire in Motor Control Center 2B-52 on October 23, 2007. This issue was entered into the licensee's corrective action program as Condition Report ANO-2-2008-0060.

The finding was determined to be more than minor because it affected the protection against external factors attribute of both the Initiating Events and Mitigating Systems cornerstone. Using the Manual Chapter 0609, "Significance Determination Process," Phase 1 worksheets, the inspectors concluded that a Phase 2 evaluation was required.

The inspectors performed a Phase 2 analysis using Appendix A, "Technical Basis For At Power Significance Determination Process," of Manual Chapter 0609,

"Significance Determination Process," and the Phase 2 worksheets for Arkansas Nuclear One. The inspectors determined that the Phase 2 presolved table and worksheets did not contain appropriate target sets to estimate accurately the risk impact of the finding, therefore, a senior reactor analyst performed a Phase 3 analysis. The estimated change in core damage frequency was 8.463E-7/yr.

The estimated change in large early release frequency was 4.842E-8/yr.

Therefore, the significance of the finding was determined to be

Green.

The cause of this finding was determined to have a crosscutting aspect in the area of problem identification and resolution associated with the corrective action program (P.1[c]) in that the licensee failed to thoroughly evaluate the fire in Motor Control Center 2B-22 such that the resolution addressed the cause and extent of condition. This also includes conducting effectiveness reviews of corrective actions to ensure that the issue was resolved after more indications were discovered. (Section 2.2)

Green.

The inspectors identified a noncited violation of 10 CFR Part 50,

Appendix B, Criterion XVI, Corrective Action, for the licensees failure to take adequate corrective actions in response to a motor control center fire that occurred on October 24, 2000. Specifically, the licensee had identified dust and dirt in the motor control center as a condition adverse to quality, assigned a corrective action for the condition, and subsequently closed the corrective action without correcting the condition. This issue was entered into the licensee's corrective action program as Condition Reports ANO 2-2007-1566,

ANO-2-2008-0050, and ANO-2-2008-0071.

The finding was determined to be more than minor because it affected the protection against external factors attribute of the Initiating Events cornerstone, and it directly affected the cornerstone objective to limit the likelihood of those events that upset plant stability and challenge critical safety functions during shutdown as well as power operations. Using the Manual Chapter 0609,

Appendix F, Fire Protection Significance Determination Process, Phase 1 worksheet, the finding was determined to have very low safety significance because the condition represented a low degradation of fire prevention and administrative controls feature. The finding had crosscutting aspects in the area of problem identification and resolution associated with the corrective action program P.1[d]) because the licensee failed to take appropriate corrective actions to address safety issues in a timely matter. (Section 2.3)

Licensee-Identified Violations

None.

REPORT DETAILS

1.0 SPECIAL

INSPECTION SCOPE

The NRC conducted a special inspection at Arkansas Nuclear One (ANO) to better understand the circumstances surrounding a fault in a breaker cubicle which resulted in a brief fire in an electrical panel resulting in the loss of a division of safety equipment on October 23, 2007. On this occasion centrifugal charging Pump A was undergoing 18-month surveillance testing following mechanical maintenance. During the testing, the pump was started locally at the charging pump breaker cubicle; following that, the pump was immediately started remotely from the control room. During the remote start, a fire occurred in the charging pump breaker cubicle which resulted in Motor Control Center (MCC) 2B-52 de-energizing due to load center Breaker 2B-532 tripping. The loss of MCC 2B-52 resulted in the loss of one division of Engineered Safety Features. The fire in conjunction with the loss of one division of Engineered Safety Features resulted in operators declaring an Alert. In accordance with NRC Management Directive 8.3, it was determined that this event had sufficient risk significance to warrant a special inspection.

The team used NRC Inspection Procedure 93812, Special Inspection, to conduct the inspection. The special inspection team reviewed procedures, corrective action documents, operator logs, design documentation, maintenance records, and procurement records for the MCC. The team interviewed various station personnel regarding the event. The team reviewed the licensees preliminary root cause analysis report, past failure records, extent of condition evaluation, immediate and long term corrective actions, and industry operating experience. A list of specific documents reviewed is provided in Attachment 1. The charter for the special inspection is included as Attachment 2.

1.1 Event Summary During full power operation on October 23, 2007, mechanical maintenance was completed on Charging Pump A and the pump was undergoing 18 month surveillance testing. During the testing, the pump was started locally at the charging pump breaker cubicle; following that, the pump was immediately started remotely from the control room. During the remote start, a fire occurred in the charging pump breaker cubicle which resulted in MCC 2B-52 de-energizing due to load center Breaker 2B-532 tripping.

The following equipment was declared inoperable as a result of the load center being de-energized: Low Pressure Safety Injection Pump 2P-34A, High Pressure Safety Injection Pump 2P-89A, Emergency Diesel Generator 2K-4A, Control Room Emergency Chiller 2VE-1A, and Containment Spray Pump 2P-35A. As a result, the fire brigade was called out. The fire in MCC 2B-52 was out and no fire extinguishers were discharged.

An Alert was declared at 11:05 p.m. CDT on Unit 2 due to a fire onsite affecting one train of Engineered Safety Feature systems. Operators realigned electrical equipment in accordance with plant procedures and the Alert was exited at 1:33 a.m. CDT.

The time line below describes the major events following the start of the Charging Pump A on October 23, 2007.

October 23, 2007 10:50 p.m.

Charging Pump A filled and vented.

10:55 p.m.

At the breaker, locally started charging Pump A for 18-month surveillance test in accordance with Procedure OP-2305.016, Remote Feature Periodic Testing.

10:56 p.m.

Secured charging Pump A. Placed the local remote switch to remote.

10:58 p.m.

Control room attempted to start charging Pump A. Fire occurred in Breaker 2B-52A5 cubicle.

MCC 2B-52 de-energized when Breaker 2B-532, MCC 2B-52 supply breaker tripped automatically on over voltage.

Entered Procedure OP-2203.034, fire and explosion abnormal operating procedure (AOP).

Entered the following Technical Specifications (TS) due to MCC 2B-52 fire:

TS 3.5.2 for Low Pressure Safety Injection Pump 2P-34A, and High Pressure Safety Injection Pump 2P-89A being inoperable TS 3.4.4 for pressurizer proportional heater Group 1 being inoperable TS 3.8.1.1 for Emergency Diesel Generator 2K-4A being inoperable TS 3.7.6.1 for control room emergency ventilation and Air Conditioning System 2VE-1A being inoperable TS 3.6.2.1 for containment spray Pump 2P-35A being inoperable TS 3.7.3.1 for Loop 1 service water header being inoperable TS 3.6.3.1 for containment isolation valves being inoperable TS 3.7.1.2 for emergency feedwater Pump 2P-7B being inoperable due to Loop 1 of service water being inoperable

TS 3.6.2.3 for a containment cooler being inoperable due to Loop 1 of service water being inoperable 11:04 p.m.

Fire in MCC 2B-52 is out.

No extinguishers were discharged.

Reflash watch is set.

11:05 p.m.

Declared an Alert on Unit 2 due to fire in MCC 2B-52. Emergency Action Level 7.6, Fire or explosion onsite affecting one train of any ESF system.

11:12 p.m.

NRC notified of Unit 2 Alert declaration.

1:33 a.m.

Terminated the Alert.

1.2 Operator and Plant Response to the Event The team assessed the response of the control room operators to the MCC fire and loss of a division of safety equipment. The team reviewed operator logs and plant computer data to evaluate operator performance in coping with the event and transient and verified that operator actions were in accordance with the response required by plant procedures and training. The team also conducted interviews with the control room operators who were on shift the night of the event.

The team concluded the operators acted appropriately to respond to the MCC fire and Alert declaration. The inspectors also concluded the operators acted promptly and appropriately in entering required TSs for safety equipment that was de-energized due to the breaker fire and the emergency declaration.

The inspectors also reviewed operator logs, alarm history, and available trend information to evaluate the plant response to the loss of the division of safety equipment.

The inspectors concluded the MCC breakers and electrical system functioned as described in the Final Safety Analysis Report. Following the fire in the charging pump breaker cubicle, MCC 2B-52 de-energized due to the load center Breaker 2B-532 tripping as designed. The inspectors also concluded the integrated plant response to the overall event occurred as described in the Final Safety Analysis Report.

1.3 Root Cause Evaluation The inspectors reviewed and assessed the licensees root cause analysis for technical accuracy, thoroughness, and corrective actions proposed and taken. The inspectors reviewed the scope and processes used by licensee personnel to identify the root cause of the fault and fire in MCC 2B-52. The inspectors compared information gained through inspection to the event information and assumptions made in the root cause reports.

The inspectors interviewed licensee personnel, reviewed logs, and reviewed personal statements. The inspectors evaluated the licensees extent of condition review and common cause evaluation.

The licensee entered the MCC 2B-52 fault and fire issue in the corrective action program (CAP) as CR ANO-2-2007-1512 and performed an RCE in response to determine the cause of the fault. Evaluation techniques utilized by the licensee included a failure modes analysis. Through this effort, the licensee determined that a high resistance connection at the bus/stab interface combined with the high starting current associated with large loads was the cause of this event. While the licensee concluded that the exact root cause could not be determined because of the damage sustained by the bus/stab contact surfaces during the event, the licensee was able to identify that the most probable root causes were inadequate preventative maintenance and inadequate original design.

To better understand the damage mechanism the stab caused to the bus bar when not lubricated, the licensee performed shop testing with subsequent laboratory analysis. The shop testing demonstrated that when not lubricated, the stabs caused noticeable damage to the tin coating on the bus bar. The laboratory analysis further confirmed that the stabbing of the un-lubricated bus bar removed the tin coating exposing the aluminum bus bar. The licensee concluded that the preventative maintenance procedure used did not require visual inspections, nor cleaning and lubrication of the bus to stab contact surface which facilitated degradation of the MCC bus bars and also allowed this degradation to continue unrecognized. Corrective actions were identified to revise both Units 1 and 2 MCC maintenance procedures to provide guidance for inspecting, cleaning and lubricating bus/stab connections; to develop and implement an equivalency/modification to replace existing plated aluminum bus bars with plated copper bus bars; and to clean, inspect, and lubricate the stab/bus connections on MCC cubicles with large loads by the end of Refueling Outage 2R20.

Aspects of organizational and programmatic weakness were also evaluated by the root cause team and reviewed by the inspectors. These included the two identified root causes: preventative maintenance less than adequate and original design inadequate, as well as timeliness of completing extent of condition inspections for Breaker 2B-53 event, thermography not performed on Unit 2 safety-related MCCs, and use of operating experience.

The extent of the condition for the cause of the fault and fire in MCC 2B-52 was assessed by the root cause team because of its potential to exist in all of the other MCCs. In response, the licensee developed a list of breaker cubicles with the same risk factors that resulted in the fire in MCC 2B-52 and performed boroscopic inspections to verify that the same condition did not exist in other MCCs. This is discussed in more detail in Section 1.4 of this report. The inspectors reviewed the licensees actions and concluded that the licensees extent of condition evaluation was adequate.

The final portion of the licensees RCE consisted of a previous occurrence evaluation.

The licensee determined that there have been several previous events associated with Unit 2 that were similar in nature to the issue identified with MCC 2B-52. The licensee concluded that degraded stab connections are an industry concern. Their review also determined that there had been no missed opportunities or actions that should have been taken.

The inspectors determined that the cause evaluation for the fault and fire in MCC 2B-52 was thorough and technically sound. However, the inspectors determined that in some areas the RCE was narrowly focused and lacked rigor when evaluating some of the issues. Specific examples were the licensees previous occurrence evaluation and the organizational and programmatic weakness evaluation.

The inspectors considered the evaluation to be narrowly focused with respect to the previous occurrence evaluation since it did not fully evaluate all previous instances where breakers were discovered with similar degraded conditions. This resulted in the licensee failing to identify that there were missed opportunities and as such address this issue appropriately. This is discussed in more detail in Sections 1.6 and 2.2 of this report.

Also, the inspectors considered the licensees conclusion in the area of organizational and programmatic weakness regarding preventative maintenance as being less than adequate was narrowly focused and lacking rigor. Specifically, the licensee determined that the preventative maintenance procedure used had been developed using a preventative maintenance engineering evaluation, which had been developed by engineering based largely on vendor manual requirements, as well as other inputs. The licensee identified that Evaluation PMEE-023 provided the requirements for the Unit 2 MCCs, and that these requirements had been taken from the Periodic Inspection and Semi-annual Inspection sections of the vendor manual which did not include the requirement to lubricate the bus/stab interface. However, during the root cause investigation, the team identified that the installation section of the vendor manual had a requirement to inspect the stabs to insure they were lubricated (petroleum jelly).

However, the licensees root cause team determined that it could not be concluded that the intent of the manual was that this lubrication be repeated periodically. Furthermore, the licensee determined that while grease can serve to inhibit oxidation and limit plating damage, other inputs caution against the effects of hardened grease on connections.

Therefore, the licensee determined that there was no over-riding good practice argument for the use of grease without a supporting basis.

While the inspectors did not conclude that grease hardening was an issue, they noted that grease hardening is a well known industry issue and as such, there is a substantial amount of industry information concerning grease hardening and actions/programs to monitor for and prevent this issue. Also, the inspectors concluded that there was industry information available to the licensee that identified the need to lubricate aluminum bus bars to prevent damage and aluminum oxidation. As such, the inspectors concluded that the organizational and programmatic weakness evaluation regarding preventative maintenance was less than adequate.

1.4 Breakers Potentially Susceptible to Failure Mechanism Identified by Root Cause The licensee determined that since the identified causes of inadequate maintenance and design weaknesses existed on all ITE Series 5600 MCCs, the condition that caused the fault in MCC 2B-52 could occur in other MCCs. Furthermore, the licensee determined that certain factors, larger load sizes, and a higher number of starts when combined with the identified causes produced failures.

During their review, the licensee determined that the ITE Series 5600 MCCs were installed primarily in 480 VAC applications on Unit 2, but similar MCCs had been added to both Units 1 and 2 as later design additions. As such, the similar MCCs were assumed to be susceptible to the same condition if the same casual factors existed.

Based on this, the licensee determined that there were over 900 active cubicles installed in ITE Series 5600 model MCCs in both units. As such, the licensee determined that it was not feasible to perform inspections of all of these cubicles in the short term so the licensee prioritized their inspection efforts by developing a list of cubicles with the same risk factors that resulted in the fault in MCC 2B-52. This prioritization produced a list of 167 potentially susceptible cubicles with a weighting factor from 0-7, where the higher the rating indicated the higher the probability of stab damage occurs. Of these 167, the licensee immediately inspected the top 29 cubicles, which were weighted as a 4 or higher.

During their initial inspections of the 29 cubicles, the licensee identified 3 cubicles that appeared to exhibit indications of stab to bus bar degradation. The identified cubicles were Breaker 2B-62A5, charging Pump 2P-36B, Breaker 2B-64J3, turbine generator turning gear and Breaker 2B-42C6, stator water cooling Pump 2P-25B. Subsequently, the licensee determined that the indications observed on Breaker 2B-42C6 stator water cooling Pump 2P-25B was due to discolored grease on the bus bar.

The inspectors noted that the licensee initially focused on breaker cubicles with a weighting factor of 4 or higher. During their review, the inspectors determined that there were previous repetitive occurrences of degradation associated with breakers that the licensee had classified as having a weighting factor of 3. The inspectors informed the licensee of this and the licensee subsequently expanded the scope of their review to encompass breakers with a weighting factor of 3 or higher.

During expanded scope inspections, the licensee identified two additional breakers that exhibited indications of bus to stab degradation. The identified cubicles were Breaker 2B-26D1/D2, auxiliary building extension Chiller 2VCH-3B and Cubicle 2B-26G5, auxiliary building extension radiological waste exhaust Fan 2VEF-51B.

The licensee de-energized and removed from service all cubicles that were determined to have degradation.

1.5 Evaluation of Operability Determination for Degraded Breakers The licensee identified a total of five breaker cubicles that appeared to exhibit signs of bus to stab degradation. Of these cubicles, four were de-energized and removed from service pending repair. The cubicle that was not de-energized, Breaker 2B-42C6, stator water cooling Pump 2P-25B was evaluated by the licensee as functional in CR ANO-2-2007-1525.

Stator water cooling Pump 2P-25B was classified as a high risk maintenance rule component, and as such, the licensee performed a functionality assessment of its condition. During their assessment, the licensee identified that the cubicle appeared to be showing signs of degradation and overheating at the stab to bus connection.

However, the licensee determined that this degradation did not prevent the pump from

performing its function. The licensee identified that the cubicle had a work request written to remove the cubicle and inspect the stabs and bus bars for degradation, and that the degradation present did not prevent the pump from performing its function. The licensee also cited that Pump 2P-25B had been the running stator water cooling pump from May 2007 through October 2007. Based on this, the licensee determined that stator water cooling Pump 2P-25B remained functional.

The inspectors reviewed the licensees CR and functionality determination associated with the stator water cooling pump. The inspectors determined that the licensees functionality assessment was not adequate to support the continued use of the pump.

The fact that a work order had been written to inspect the cubicle stabs and bus bars at some point in the future and that the pump had run for the previous five months was not relevant to the condition that was being evaluated and was determined to not be adequate bases for functionality.

The inspectors informed the licensee of their concerns associated with stator water cooling Pump 2P-25B. Subsequently, the licensee initiated CR ANO-2-2007-1575 to re-evaluate the issue. During subsequent review, the licensee was able to determine that the indications observed associated with the stator water cooling pump were in fact a result of discolored grease on the bus bar.

1.6 Event Precursors The inspectors performed a review of the licensees CAP database as well as the facilities maintenance database to determine if previously identified MCC problems could have been viewed as precursors to the event on October 23, 2007. During this review, the inspectors considered previously documented issues where stab to bus bar degradation had been identified as well as any actual breaker fire events. The inspectors identified five previous events that appeared to be similar to that identified on Breaker 2B-52A5. Specifically,

  • In April 1998, during performance of preventative maintenance on Breaker 2B-26C1, Auxiliary Building Extension Chiller 2VCH-3A, the Phase B stab was found to be welded to its associated bus bar.
  • In September 1999, during performance of preventative maintenance on Breaker 2B-26C1, the middle phase stab was discovered to be welded to its associated bus bar.
  • In October 2000, while performing postmodification testing of Main Chill Water Pump 2VP-1B, Unit 2 experienced a loss of MCC 2B-22 and a fire inside Breaker Cubicle 2B-22A5, the breaker for the main chiller water pump.
  • In October 2001, Breakers 2B-21A6, Heating Boiler Hot Water Circulating Pump 2VP-4B, and Breaker 2B-26D1, Auxiliary Building Extension Chiller 2VCH-3B, were found with burnt bus bars.
  • In November 2006, molten metal was identified on the Phase A bus bar of Breaker 2B-26H5, Regeneration System Air Blower 2C-29.

Based on this, the inspectors determined that there had been event precursors documented by the licensee in various facility databases. As such, the inspectors concluded that the licensee had failed to recognize and evaluate all breakers that had exhibited degraded conditions which were similar. This resulted in the licensee failing to recognize and analyze pertinent information about previous breaker issues which were precursors to the event in October 23, 2007.

1.7 MCC Maintenance and Testing The inspectors reviewed the licensees program for maintenance and inspection of the MCCs, particularly as it related to the historical health of the breakers and ability to recognize and identify material deficiencies. During their review the inspectors noted that the licensees generic preventative maintenance frequency for MCCs was every 6 years, and most of the nonsafety related MCCs were set to this periodicity. However, the safety-related MCCs periodicity was every 9 years. This was based on the licensees determination that the safety-related MCCs were located in clean areas. The inspectors also noted that Procedure OP-2412.074, Unit 2 Motor Control Centers, Revision 6, was the licensees procedure used for performance of their preventative maintenance task on the MCCs. This procedure only required cleaning in the MCC housing where accessible and appropriate, and generally only directed the cleaning of the interior of the breaker cubicle without removing it from the MCC housing.

The inspectors determined that the licensees program was not in accordance with industry standards for MCC maintenance. Specifically, the industry standard is to clean and inspect inside of the MCC housing during maintenance to maintain the area clear of dust and dirt. The inspectors determined that, since the interior of the MCCs were not readily accessible from the rear; the licensee was not performing interior cleaning of the MCC housings. Based on this, the inspectors determined that the licensees program was not adequate to recognize and identify material deficiencies of breakers. A finding associated with this issue is described in Section 2.3 of this report.

1.8 Industry Operating Experience (OE) and Potential Generic Issues The inspectors performed searches of OE databases and other sources to identify reports of similar problems, both inside and outside the nuclear industry. The inspectors conducted interviews of licensee personnel, reviews of pertinent OE materials discovered independently as well as with the assistance of the NRCs OE section, and an evaluation of actions taken by the licensee in response to relevant OE.

The inspectors determined that the licensee had appropriately reviewed and incorporated OE associated with the circumstances of other MCC/breaker issues, and that a failure to incorporate applicable OE into station practices was not a contributing cause to the fault in MCC 2B-52. The inspectors reviewed several items of OE, inspection reports, and licensee event reports. It appeared to the inspectors that the licensee had accounted for all available OE at the time that could have reasonably been obtained and reviewed.

2.0 SPECIAL INSPECTION FINDINGS 2.1 Inadequate Maintenance Procedure for MCC Breakers A self-revealing noncited violation was identified associated with the licensees failure to comply with Unit 2 Technical Specifications, Section 6.4.1, Procedures, for the failure to ensure adequate procedures were available for maintenance that was conducted on the Unit 2 motor control centers. Specifically, the maintenance procedure used by the licensee did not require visual inspections, nor cleaning, and lubrication of the bus to stab contact surface which facilitated degradation of the motor control center bus bars and also allowed this degradation to continue unrecognized.

On October 23, 2007, Unit 2 operations were in the process of performing an 18 month surveillance testing on Charging Pump 2P-36A in accordance with Procedure OP-2305.016, Remote Features Periodic Testing, Revision 21. This surveillance tests the local/remote start feature of the charging pump to ensure that it operates correctly from the selected station. The charging pump was started and secured by an operator at MCC 2B-52 using the local control station. Control was then transferred to the remote station and control room operators attempted to start the Charging Pump A to complete testing. As the pump was being started, a fault occurred in MCC 2B-52 Breaker 2B-52A5. The local operator at MCC 2B-52 reported a flash, followed by smoke, and fire. Concurrently, Feeder Breaker 2B-532 tripped, de-energizing MCC 2B-52, which resulted in the loss of one train of Engineered Safety Features. The Unit 2 control room also received a fire alarm for the affected area and entered AOP OP-2203.034, Fire or Explosion. In response to this condition, Unit 2 operators declared an Alert based on a fire or explosion with loss of one train of Engineered Safety Features.

The licensee performed an RCE of this event as documented in CR ANO-2-2007-1512.

During this evaluation, the licensee identified that high resistance connection at the stab/bus interface combined with high starting current associated with large loads was the cause of this event. The licensee concluded that the exact root cause could not be determined because of the damage that was sustained during the event but the licensee identified as a probable root cause that preventative maintenance was less than adequate. Specifically, preventative maintenance Procedure OP-2412.074, Unit 2 AC Motor Control Centers, Revision 6, does not require visual inspections and cleaning/lubrication of the bus/stab contact surface, which is contrary to standard industry practice and cubicle installation instructions contained in the vendor technical manual. Also, this practice allowed degradation of the stab to bus connection to continue unrecognized.

The licensee determined that maintenance technicians did not use lubricant on stabs or bus bars when inserting the ITE Series 5600 breaker cubicles, nor was lubrication required/recommended by maintenance Procedure OP-2412.074, Unit 2 AC Motor Control Centers. However, ITE Series 5600 Technical Document TD I005 0150, General Instructions Motor Control Center Series 5600, Revision 1, recommends that the stab fingers be lubricated with petroleum jelly prior to insertion.

The licensee was able to determine that during the mid 1980s, common maintenance Procedure OP-1403.085, MCC Maintenance, had contained a step to apply NO-OX-ID grease to the breaker stabs. Subsequently, Procedure OP-1412.054, Unit 1 AC Motor Control Centers, superseded Procedure OP-1403.085, Motor Control Center Maintenance, in 1989, and this procedure did not require maintenance technicians to lubricate the breaker stabs. Procedure OP-2412.074, Unit 2 AC Motor Control Centers, was issued in 1993 and also did not require lubrication of the breaker stabs.

The inspectors reviewed the licensees RCE of this event. During their review, the inspectors noted that the use of lubrication during the installation of MCC breakers was an established industry practice. The inspectors also noted that Unit 2 uses aluminum bus bars coated with tin, and as such, there is industry operating experience that identifies that any damage to the coating will lead to the formation of aluminum oxide which is known to cause a localized high resistance point. The inspectors noted that the industry operating experience that identified the importance of using the proper lubrication to prevent damaging the bus bars and inhibit oxide formation was available to the licensee.

The inspectors also noted that the licensee performed testing of an undamaged portion of bus bar. This testing consisted of 30 stabs with an un-lubricated bar and 30 stabs with a lubricated bar. The licensee determined that there was noticeable wear of the tin coating on the un-lubricated bar, whereas the lubricated bar showed little wear. The licensee also performed a metallurgical examination of this bus bar and stab as documented in Metallurgical Examination of Bus Bar and Stab From Electrical Equipment 2B26H5 ANO-2. In this analysis it was noted that the bus bar and stab both showed signs of coating damage from the un-lubricated damage.

The safety significance and enforcement aspects of this finding are described in Sections 3.1 and 4.1, respectively.

2.2 Failure to Identify, Correct, and Prevent Recurrence of a Significant Condition Adverse to Quality A self-revealing noncited violation of 10 CFR Part 50, Appendix B, Criterion XVI, Corrective Actions, was identified associated with the licensees failure to implement adequate corrective actions to prevent recurrence of a significant condition adverse to quality. Specifically, during the Root Cause Evaluation performed for the fire in Motor Control Center 2B-22 in October 2000, the licensee failed to recognize and evaluate previously documented instances where other breakers exhibited degraded connections that were similar, and as such, were precursors to the failure of the breaker in Motor Control Center 2B-22. Also, the licensee failed to recognize and evaluate these same

degraded breaker connection conditions that were discovered during extent of condition inspections and subsequent motor control center maintenance inspections. The licensees failure to identify and evaluate all instances of degraded breaker connections contributed to their failure to adequately identify the cause and implement corrective actions to prevent recurrence of this significant condition adverse to quality On October 23, 2007, while Unit 2 Operations was in the process of performing testing on charging Pump 2P-36A in accordance with Procedure OP-2305.016, Remote Features Periodic Testing, Revision 21, a fault occurred in MCC 2B-52 Breaker 2B-52A5. This fault resulted in a fire in the MCC and also resulted in Feeder Breaker 2B-532 tripping, de-energizing MCC 2B-52 and resulting in the loss of one train of Engineered Safety Features. The licensee entered this issue into their CAP as CR ANO-2-2007-1512, and performed an RCE of this event, as documented in this CR.

During the inspectors review of this event, they determined that a previous fire in MCC 2B-22 was caused by similar circumstances. Specifically, on October 24, 2000, while an operator was attempting to start Main Chill Water Pump 2VP-1B for postmodification testing, lights in the room went out and the pump did not start. The operator went to MCC 2B-22 and noted smoke coming from the MCC, all of the indicating lights on the MCC off, and fire in the Main Chill Water Pump 2VP-1B Breaker 2B-22A5, which was extinguished by the operator with a CO2 fire extinguisher. The licensee entered this issue into their CAP as CR ANO-2-2000-0766.

Subsequently, on October 25, 2000, while performing extent of condition inspections in response to the fire in MCC 2B-22, the Phase B stab on Breaker 2B-11A6, Heating Boiler Water Circulating Pump 2VP-4A, was found to be damaged by heat and arcing where contact between the stab and bus bar was made. The licensee entered this issue into their CAP as CR ANO-2-2000-0767, which was subsequently closed to CR ANO-2-2000-0766 for resolution.

The licensee performed an RCE of these events, as documented in CR ANO-2-2000-0766. During this process, the licensee identified that the center stab of Breaker 2B-22A5 appeared to have suffered previous damage. The licensee concluded that based on the MCC design, the fault condition should not have resulted in bus bar degradation unless there was already a high resistance stab connection. Based on this, the licensee determined that on October 24, 2000, the high inrush starting current caused the center stab of Breaker 2B-22A5 to emit an arc and a small amount of molten metal which resulted in a fire and subsequent Phase 3 fault which caused Feeder Breaker 2B-213 to trip which de-energized MCC 2B-22. The licensee determined the root cause of this event to be a degraded subcomponent. Specifically, the stabs on the breaker did not exert enough tension on the bus bar to support the high starting current without damage to the bus bars and stabs. The licensee also determined that the root cause for the condition discovered on Breaker 2B-11A6 to be the same.

The inspectors reviewed the licensees RCE for this event. During this review, the inspectors noted that the licensee had identified that there had been events both at ANO and other sites where arcing was involved but did not consider them to be applicable because none of these events had led to a fire. The inspectors questioned this position based on the licensees determination that there had been previous damage on the bus bars of Breaker 2B-22A5 that had not resulted in a fire as well as the degradation observed on Breaker 2B-11A6 that had not resulted in a fire. The inspectors conducted a review of previously documented issues where stab to bus bar degradation was identified and noted two previous events where degradation appeared to be similar to that identified on Breakers 2B-22A5 and 2B-11A6. Specifically:

  • In April 1998, during performance of preventative maintenance on Breaker 2B-26C1, Auxiliary Building Extension Chiller 2VCH-3A, the Phase B stab was found to be welded to its associated bus bar. The licensee initiated Job Order (JO) 00754703 to replace the affected bus bar and breaker stab.
  • In September 1999, during performance of preventative maintenance on Breaker 2B-26C1, the middle phase stab was discovered to be welded to its associated bus bar. The licensee initiated Job Order 796818 to replace the affected bus bar and breaker stab.

The inspectors determined that the licensees decision to not evaluate previous events based solely on the fact that these events had not resulted in a fire was not appropriate and was narrowly focused. Specifically, the inspectors determined that this criterion was not representative of all of the conditions identified and being evaluated by the licensee in the RCE. As such, the inspectors determined that the licensee had not adequately investigated and evaluated these previous instances where breakers where discovered with similar degraded conditions. This resulted in the licensee overlooking pertinent information that was available for the identification of the failure mechanism as well as the actual root cause of the failure.

The inspectors also noted that the licensee had used a failure modes analysis (FMA) to determine the root cause. Through the FMA the licensee had determined that the potential failure causes Number 3, High resistance connection, and Number 19, Contacts spread from repeated installation and lost tension or were faulty and never had enough tension, with all the evidence substantiated the root cause of faulty stabs. The inspectors questioned the licensees conclusion based on the FMA data. Specifically, the refuting evidence for the stab tension as a potential failure condition identified that there was not a history of repeated installations of this breaker, along with no substantiated supporting evidence. The inspectors also noted that, in the previous breakers with degraded conditions, loose spring clips had not been identified nor had loose spring clips been found with degradation in any of the extent of condition inspections. Furthermore, the inspectors noted there had been a subsequent similar degraded condition identified on a Unit 2 breaker during performance of maintenance that had not been evaluated for applicability. Also in each of these conditions, the inspectors noted that spring clip tension was not identified as an issue. Specifically, in October 2001, Breakers 2B-21A6, Heating Boiler Hot Water Circulating Pump 2VP-4B, and 2B-26D1, Auxiliary Building Extension Chiller 2VCH-3B, were found with burnt bus

bars. The licensee entered these issues into the CAP as CRs ANO-2-2001-1091 and ANO-2-2001-1108 and generated maintenance Action Items 55722 and 55715 to replace the affected bus bars. Subsequently, these CRs were closed to trend with no further investigation or review performed.

The inspectors also noted that in November 2006, molten metal was identified on the Phase A bus bar of Breaker 2B-26H5, Regeneration System Air Blower 2C-29. The licensee entered this into their CAP as CR ANO-2-2006-2568 and performed an apparent cause evaluation of this issue. In this evaluation, the licensee had determined that the cause of the degradation was poor cubicle insertion. The inspectors questioned this determination because the licensee had verified that the cubicle was fully inserted and was not able to determine when the cubicle was last removed or reinstalled. The inspectors determined that this was another example of the licensees failure to recognize and evaluate the same degraded breaker connection conditions that had previously been identified.

The inspectors concluded that the licensee failed to accurately identify the root cause of the fire in MCC 2B-52A5 as well as the degradation in Breaker 2B-11A6 using all available pertinent data. The inspectors determined that the root cause for these issues was the same as that identified in CR ANO-2-2007-1512; preventative maintenance was less than adequate. Specifically, preventative maintenance procedures did not require visual inspections and cleaning/lubrication of the bus/stab contact surface.

The safety significance and enforcement aspects of this finding are described in Sections 3.2 and 4.2, respectively.

2.3 Inadequate Implementation of Corrective Actions Fail to Correct a Condition Adverse to Quality The inspectors identified a noncited violation of 10 CFR Part 50, Appendix B, Criterion XVI, Corrective Action, for the licensees failure to take adequate corrective actions in response to a motor control center fire that occurred on October 24, 2000.

Specifically, the licensee had identified dust and dirt in the motor control center as a condition adverse to quality, assigned a corrective action for the condition, and subsequently closed the corrective action without correcting the condition.

On October 23, 2007, while Unit 2 operations was in the process of performing testing on Charging Pump 2P-36A in accordance with Procedure OP-2305.016, Remote Features Periodic Testing, Revision 21, a fault occurred in MCC 2B-52 Breaker 2B-52A5. This fault resulted in a fire in the MCC and also resulted in Feeder Breaker 2B-532 tripping de-energizing MCC 2B-52 resulting in the loss of one division of Engineered Safety Features.

As part of the inspectors review of this issue, walkdowns of the affected equipment and area were conducted. During these walkdowns following the event, the inspectors noted a large amount of dust and dirt internal to MCC 2B-52. The inspectors inquired about the dust and dirt that was present in the MCC and were informed by the licensee that this was not uncommon because they did not remove the breaker cubicles from the MCC

during clean and inspect maintenance but merely wiped down the inside of the breaker cubicles.

The inspectors questioned the licensees response based on the review of a previous similar event where dust and dirt had been identified as a contributing cause to a fire in another MCC. Specifically, on October 24, 2000, while starting main chiller chilled water Pump 2VP-1B for postmaintenance testing, a fire occurred in MCC 2B-22 Breaker 2B-22A5. This resulted in Feeder Breaker 2B-213 tripping which de-energized MCC 2B-22. The licensee performed a Root Cause Analysis of this event as documented in CR CR-ANO-2-2000-0766. In their Root Cause Analysis the licensee identified as a contributing cause that preventative maintenance activities for MCCs were less than adequate because the procedure allowed for steps requiring cleaning of the internal of the MCCs to not be performed and that accumulated dust and dirt created an environment where an ignition source could create a fire. Based on this, the licensee had initiated Corrective Action 9 to CR ANO-2-2000-0766 to correct this condition.

The inspectors noted that the licensee subsequently determined that dust and dirt was not a contributing cause to the fire in MCC 2B-22. However, the inspectors determined that this issue was a condition adverse to quality, and as such, determined the licensee had not adequately addressed the issue. Specifically during their review, the inspectors determined that the licensee had closed this corrective action to the stations preventative maintenance optimization program for resolution. Subsequently, the preventative maintenance optimization program closed the action without resolution of this issue. The licensee entered this into their CAP as CRs ANO-2-2007-1566, ANO-2-2008-0050, and ANO-2-2008-0071.

The safety significance and enforcement aspects of this finding are described in Sections 3.3 and 4.3, respectively.

3.0 ASSESSMENT 3.1 Inadequate Maintenance Procedure for MCC Breakers The inspectors determined that the licensees failure to ensure that adequate procedures were available for maintenance conducted on MCC 2B-52 was a performance deficiency. The finding was determined to be more than minor because it affected the protection against external factors attribute of both the Initiating Events and Mitigating Systems cornerstone. Using the Manual Chapter 0609, Significance Determination Process, Phase 1 Worksheets, the inspectors concluded that a Phase 2 evaluation was required.

The finding was determined to be more than minor because it affected the protection against external factors attribute of both the Initiating Events and Mitigating Systems cornerstone. Using the Manual Chapter 0609, "Significance Determination Process,"

Phase 1 worksheets, the inspectors concluded that a Phase 2 evaluation was required.

The inspectors performed a Phase 2 analysis using Appendix A, "Technical Basis For At Power Significance Determination Process," of Manual Chapter 0609, "Significance

Determination Process," and the Phase 2 worksheets for Arkansas Nuclear One. The inspectors determined that the Phase 2 presolved table and worksheets did not contain appropriate target sets to estimate accurately the risk impact of the finding, therefore, a senior reactor analyst performed a Phase 3 analysis. The estimated change in core damage frequency was 8.463E-7/yr. The estimated change in large early release frequency was 4.842E-8/yr. Therefore, the significance of the finding was determined to be Green.

3.2 Failure to Identify, Correct, and Prevent Recurrence of a Significant Condition Adverse to Quality The finding was determined to be more than minor because it affected the protection against external factors attribute of both the Initiating Events and Mitigating Systems cornerstone. Using the Manual Chapter 0609, "Significance Determination Process,"

Phase 1 worksheets, the inspectors concluded that a Phase 2 evaluation was required.

The inspectors performed a Phase 2 analysis using Appendix A, "Technical Basis For At Power Significance Determination Process," of Manual Chapter 0609, "Significance Determination Process," and the Phase 2 worksheets for Arkansas Nuclear One. The inspectors determined that the Phase 2 presolved table and worksheets did not contain appropriate target sets to estimate accurately the risk impact of the finding, therefore, a senior reactor analyst performed a Phase 3 analysis. The estimated change in core damage frequency was 8.463E-7/yr. The estimated change in large early release frequency was 4.842E-8/yr. Therefore, the significance of the finding was determined to be Green. The cause of this finding was determined to have a crosscutting aspect in the area of problem identification and resolution associated with the corrective action program (P.1[c]) in that the licensee failed to thoroughly evaluate the fire in Motor Control Center 2B-22 such that the resolution addressed the cause and extent of condition. This also includes conducting effectiveness reviews of corrective actions to ensure that the issue was resolved after more indications were discovered.

3.3 Inadequate Implementation of Corrective Actions Fail to Correct a Condition Adverse to Quality The inspectors determined that the licensees failure to perform adequate corrective actions for a condition adverse to quality associated with inadequate preventative maintenance activities of MCCs was a performance deficiency. The finding was determined to be more than minor because it affected the protection against external factors attribute of the Initiating Events cornerstone, and it directly affected the cornerstone objective to limit the likelihood of those events that upset plant stability and challenge critical safety functions during shutdown as well as power operations. Using the Manual Chapter 0609, Appendix F, Fire Protection Significance Determination Process, Phase 1 Worksheet, the finding was determined to have very low safety significance because the condition represented a low degradation of fire prevention and administrative controls feature. The finding had crosscutting aspects in the area of problem identification and resolution associated with the CAP (P.1 [d]) because the licensee failed to take appropriate corrective actions to address safety issues in a timely manner.

4.0 ENFORCEMENT 4.1 Inadequate Maintenance Procedure for MCC Breakers Unit 2 Technical Specifications, Section 6.4.1.a, Procedures, requires, in part, that written procedures shall be established, implemented, and maintained covering the applicable procedures recommended in Regulatory Guide 1.33, Revision 2, Appendix A, February 1978. Regulatory Guide 1.33, Appendix A, Section 9.a., requires, in part, that maintenance that can affect the performance of safety-related equipment should be performed in accordance with written procedures, documented instructions, or drawings appropriate to the circumstances. Contrary to the above, on October 4, 2003, when maintenance was performed on MCC 2B-52 using Procedure OP-2412.074, Unit 2 AC Motor Control Centers, the licensee failed to ensure adequate procedures were available for the maintenance conducted. Because this finding is of very low safety significance and has been entered into the CAP as CR ANO-2-2007-1512, this violation is being treated as an NCV consistent with Section VI.A of the NRC Enforcement Policy:

NCV 05000368/2007009-01, Inadequate Maintenance Procedure for Motor Control Center Breakers.

4.2 Failure to Identify, Correct, and Prevent Recurrence of a Significant Condition Adverse to Quality 10 CFR Part 50, Appendix B, Criterion XVI, Corrective Actions, 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 nonconformances are promptly identified and corrected. In the case of significant conditions adverse to quality, the measures shall assure that the cause of the condition is determined and corrective action taken to preclude repetition. Contrary to the above, the licensee failed to properly evaluate and identify the cause of the breaker fire in MCC 2B-22 in October 2000. Subsequently, the corrective actions that were implemented for the identified cause were not sufficient to correct the condition and prevent repetition which resulted in a fire in MCC 2B-52 on October 23, 2007. Because this finding is of very low safety significance and has been entered into the CAP as CR ANO-2-2008-0060, this violation is being treated as an NCV consistent with Section VI.A of the NRC Enforcement Policy: NCV 05000368/2007009-02, Failure to Identify, Correct, and Prevent Recurrence of a Significant Condition Adverse to Quality.

4.3 Inadequate Implementation of Corrective Actions Fail to Correct a Condition Adverse to Quality 10 CFR Part 50, Appendix B, Criterion XVI, Corrective Action, requires, in part, that measures be established to assure that conditions adverse to quality are promptly identified and corrected. Contrary to this, between June 2001 and October 2007, the licensees measures failed to assure that a condition adverse to quality was promptly corrected. Specifically, the licensee had identified dust and dirt internal to the station MCCs as a condition adverse to quality, assigned a corrective action to address this condition, and subsequently closed this corrective action without resolution of the issue.

Because this finding is of very low safety significance and has been entered into the CAP

as CR ANO-2-2008-0071, this violation is being treated as an NCV consistent with Section VI.A of the NRC Enforcement Policy: NCV 05000368/2007009-03, Inadequate Implementation of Corrective Actions Fail to Correct a Condition Adverse to Quality.

4OA6 Meetings, Including Exit

On November 6, 2007, and January 10, 2008, the results of this inspection were presented to T. Mitchell, Vice President Nuclear Generation, and other members of his staff who acknowledged the findings. Additionally, on February 20, 2008, the final results of this inspection were presented to B. Berryman, Plant General Manager, and other members of his staff who acknowledged the findings. The inspector confirmed that no proprietary material was examined during the inspection.

ATTACHMENT 1:

SUPPLEMENTAL INFORMATION

KEY POINTS OF CONTACT

Licensee Personnel

B. Berryman, General Manager, Plant Operations
C. Bregar, Nuclear Safety Assurance Director
J. Browning, Manager, Maintenance
L. Cawyer, Reactor Operator
S. Cotton, Manager, Training & Development
B. Efrid, Reactor Operator
J. Eichenberger, Director, Nuclear Safety
D. James, Licensing Manager
J. Miller, System Engineering Manager
T. Mitchell, Vice President, Operations
C. Reasoner, Engineering Director
R. Scheide, Licensing Specialist
J. Smith, Quality Assurance Manager
W. Strickland, Senior Reactor Operator
F. Van Buskirk, Licensing Specialist
R. Walters, Operations Manager
M. Woodby, Design Engineering Manager

LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED

Opened and Closed

05000368/2007009-01 Inadequate Maintenance Procedure for Motor Control Center NCV Breakers
05000368/2007009-02 Failure to Identify, Correct and Prevent Recurrence of A NCV Significant Condition Adverse to Quality
05000368/2007009-03 Inadequate Implementation of Corrective Actions Fail to NCV Correct a Condition Adverse to Quality

LIST OF DOCUMENTS REVIEWED