ML13182A428

IR 05000261-13-008, 01/01/2013 - 03/30/2013, Carolina Power and Light Company, H.B. Robinson Steam Electric Plant, Unit 2, Maintenance Effectiveness

ML13182A428
Person / Time
Site:	Robinson
Issue date:	07/01/2013
From:	Croteau R P Division Reactor Projects II
To:	Gideon W R Progress Energy Co
References
EA-13-129 IR-13-008
Download: ML13182A428 (16)

See also: IR 05000261/2013008

Text

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UNITED STATES NUCLEAR REGULATORY COMMISSION

REGION II 245 PEACHTREE CENTER AVENUE NE, SUITE 1200 ATLANTA, GEORGIA 30303-1257

Enclosures transmitted herewith contain SUNSI. When separated from Enclosure 2 this

document is decontrolled.

LIMITED INTERNAL DISTRIBUTION PERMITTED

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July 1, 2013

EA-13-129

Mr. William R. Gideon

Vice President

Progress Energy H. B. Robinson Steam Electric Plant, Unit 2 3581 West Entrance Rd

Hartsville, SC 29550

SUBJECT: H.B. ROBINSON STEAM ELECTRIC PLANT - NRC INSPECTION REPORT

05000261/ 2013008; PRELIMINARY WHITE FINDING AND APPARENT VIOLATION

Dear Mr. Gideon:

On March 30, 2013, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your H. B. Robinson Steam Electric Plant Unit 2. The enclosed inspection report documents

the inspection results which were discussed on May 22, 2013 and June 25, 2013, with you and

other 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 enclosed inspection report discusses one finding that has preliminarily been determined to be a White finding with low to moderate safety significance that may require additional NRC inspections. As described in the enclosed report, the finding involved the failure to perform

adequate preventive maintenance on the dedicated shutdown diesel generator (DSDG) cooling

system, in accordance with vendor recommendations and as required by procedure PLP-018,

"Quality Assurance Program for Non-Safety Sy

stems and Equipment used to meet the Station Blackout rule" and Fire Safe Shutdown (SSD) equipment maintenance requirements. During surveillance testing of the DSDG on October 2, 2012, the DSDG automatically shut down on high engine temperature due to a failure of the radiator drive belts. The condition of the drive belts was significantly degraded due, in part, to a lack of adequate inspection, maintenance,

and/or periodic replacement, which would have rendered the plant unable to cope for eight

hours after a postulated station blackout, or provide emergency power for certain selected Fire

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W. Gideon 2

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Safe Shutdown (SSD) scenarios. The DSDG was subsequently repaired and returned to service. Since the DSDG was last successfully run on August 28, 2012, the exposure time for

the failure to run was from this date until October 03, 2012, when immediate corrective actions

were taken to replace the drive belts. No actual event requiring the use of the DSDG occurred

during this period.

This finding was assessed based on the best available information, using the applicable Significance Determination Process (SDP) in accordance with Inspection Manual Chapter (IMC) 0609. The basis for the NRC staff's preliminaril

y significance determination is provided as an enclosure to this letter.

The finding is also an apparent violation (AV) of NRC requirements set forth in 10 CFR 50.63 (c)(2) because you failed to have the DSDG (identified as the alternate ac power source)

capable of withstanding a station blackout for the specified coping period. This violation is being considered for escalated enforcement action in accordance with the Enforcement Policy, which

can be found on the NRC's Web site at http://www.nrc.gov/about-nrc/regulatory/enforcement/enforce-pol.html.

In accordance with NRC Inspection Manual Chapter (IMC) 0609, Significance Determination Process, we intend to complete our risk evaluations using the best available information and

issue our final significance determination within 90 days of the date of this letter. The

Significance Determination Process encourages an open dialogue between the NRC staff and the licensee; however, the dialogue should not impact the timeliness of the staff's final

determination.

Before the NRC makes its final decision on this matter, we are providing you an opportunity to

either: (1) present to the NRC your perspectives on the facts and assumptions used by the NRC to arrive at this finding and the significance at a Regulatory Conference, or (2) submit your position on this finding to the NRC in writing. If you request a Regulatory Conference, it should

be held within 30 days of the receipt of this letter and we encourage you to submit supporting

documentation at least one week prior to the conference to make the conference more efficient

and effective. If a Regulatory Conference is held, it will be open for public observation. The

NRC will also issue a press release to announce the conference. If you decide to submit only a written response, such a submittal should be sent to the NRC within 30 days of the receipt of this letter. If you decline to request either a Regulatory Conference or submit a written

response, you relinquish your right to appeal the final significance determination; in that, by not

doing either you fail to meet the appeal requirements stated in the Prerequisites and Limitations sections of Attachment 2 of IMC 0609.

If you choose to provide a written response, it should be clearly marked as "Response to

Apparent Violation in Inspection Report No. 05000261/2013008"; EA-13-129, and should

include for the apparent violation: the reason for the apparent violation, or, if contested, the

basis for disputing the apparent violation; the corrective steps that have been taken and the

results achieved; the corrective steps that will be taken to avoid further violations; and the date when full compliance will be achieved. Your response may reference or include previously docketed correspondence, if the correspondence adequately addresses the required response.

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W. Gideon 3

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If an adequate response is not received within the time specified or an extension of time has not been granted by the NRC, the NRC will proceed with its enforcement decision.

Please contact George Hopper at (404) 997-4645 within 10 days from the issue date of this

letter to notify the NRC of your intentions. If we have not heard from you within 10 days, we will

continue with our significance determination and enforcement decision. The final resolution of this matter will be conveyed in separate correspondence.

Since the NRC has not made a final determination in this matter, no Notice of Violation is being

issued for this inspection finding at this time. Please be advised that the characterization of the

apparent violation described in the enclosure may change as a result of further NRC review. You will be advised by separate correspondence of the results of our deliberations on this

matter.

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 you choose to provide one, will be made available electronically for public inspection in the NRC Public Document Room or from the NRC's Agencywide Documents Access and Management System (ADAMS), accessible from the NRC

Web site at http://www.nrc.gov/reading-rm/adams.html. To the extent possible, your response should not include any personal privacy, proprietary, or safeguards information so that it can be

made available to the Public without redaction. However, because of the security-related

information contained in Enclosure 2 and in accordance with 10 CFR 2.390, a copy of Enclosure 2 will not be available for public inspection.

Sincerely, /RA/

Richard P. Croteau, Director

Division of Reactor Projects

Docket Nos.: 50-261 License Nos.: DPR-23

Enclosures:

1. NRC Inspection Report 05000261/2013008

w/Attachment: Supplemental Information 2. Phase 3 w/Attachments: (OFFICAL USE ONLY - SECURITY RELATED INFORMATION)

cc w/encls: (See page 4)

_________________________ SUNSI REVIEW COMPLETE FORM 665 ATTACHED OFFICE RII:DRP RII:DRP RII:DRP RII:EICS RII:EICS RII:DRP RII:DRP SIGNATURE GTH /RA for/ Via email GTH /RA/ SES /RA for/ RPC /RA/ NAME JDodson CScott GHopper SSparks CEvans WJones RCroteau DATE 07/01/2013 06/28/2013 06/27/2013 06/28/2013 06/28/2013 E-MAIL COPY? YES NO YES NO YES NO YES NO YES NO YES NO YES NO

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W. Gideon 4

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cc w/encl: cc w/Inspection Summary:

Donald W. Barker

Manager, Nuclear Oversight

H. B. Robinson Steam Electric Plant, Unit 2

Progress Energy 3581 West Entrance Rd.

Hartsville, SC 29550

Richard Hightower

Supervisor Licensing/Regulatory Programs

Progress Energy

H. B. Robinson Steam Electric Plant

3581 West Entrance Road

Hartsville, SC 29550

William R. Gideon

Vice President

H. B. Robinson Steam Electric Plant, Unit 2

Progress Energy

3581 West Entrance Rd.

Hartsville, SC 29550

Thomas Cosgrove

Plant General Manager

H.B. Robinson Steam Electric Plant, Unit 2

Progress Energy 3581 West Entrance Rd.

Hartsville, SC 29550

Christos Kamilaris

Manager, Support Services H.B. Robinson Steam Electric Plant, Unit 2

Progress Energy

3581 West Entrance Rd.

Hartsville, SC 29550

Joseph W. Donahue Vice President

Nuclear Oversight

Progress Energy

TPP-15

100 E. Davie Street

Raleigh, NC 27601

Edward T. O'Neil

Director

Nuclear Protective Serv and Emergency

Preparedness

Progress Energy

TPP-15 100 East Davie Street

Raleigh, NC 27601

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W. Gideon 5

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Letter to William R. Gideon from Richard P. Croteau dated July 1, 2013

SUBJECT: H.B. ROBINSON STEAM ELECTRIC PLANT - NRC INSPECTION REPORT 05000261/ 2013008; PRELIMINARY WHITE FINDING AND APPARENT

VIOLATION

Distribution w/encls:

RidsNrrPMRobinson Resource

C. Evans, RII

L. Douglas, RII

B. Westreich, NSIR E. McNiel, NSIR RIDSNRRDIRS

OE Mail

PUBLIC

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Enclosure 1 U. S. NUCLEAR REGULATORY COMMISSION

REGION II

Docket Nos.: 50-261

License Nos.: DPR-23

Report Nos.: 05000261/2013008

Licensee: Carolina Power and Light (CP&L)

Facility: H.B. Robinson Steam Electric Plant, Unit 2

Location: 3581 West Entrance Road

Hartsville, SC 2955

Dates: January 1, 2013 - March 30, 2013

Inspectors: J. Hickey, Senior Resident Inspector C. Scott, Resident Inspector

G. McDonald, Senior Risk Analyst

Approved by: Richard P. Croteau, Director

Division of Reactor Projects

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Enclosure 1 SUMMARY OF FINDINGS

IR 05000261/2013008; January 1 - March 30, 2013; Carolina Power and Light Company, H.B.

Robinson Steam Electric Plant, Unit 2; Maintenance Effectiveness

This inspection was conducted by the resident inspectors. One Apparent Violation was

identified. The significance of most findings is indicated by their color (Green, White, Yellow, or Red) using Inspection Manual Chapter (IMC) 0609, "Significance Determination Process" (SDP) dated June 2, 2011. Findings for which the SDP does not apply may be Green or be assigned a severity level after NRC management review. Cross-cutting aspects are determined using IMC 0310 "Components Within the Cross-Cutting Areas" dated October 28, 2011. All violations of

NRC requirements are dispositioned in accordance with the NRCs Enforcement Policy dated

June 7, 2012. The NRC's program for overseeing the safe operation of commercial nuclear

power reactors is described in NUREG-1649, "R

eactor Oversight Process," Revision 4, dated December 2006.

A. NRC-Identified and Self-Revealing Findings

Cornerstone: Mitigating Systems

(TBD) An Apparent Violation (AV) of 10 CFR 50.63, "Loss of All Alternating Current Power", was identified for the licensee's failure to perform adequate preventive

maintenance on the dedicated shutdown diesel generator (DSDG) cooling system, in

accordance with vendor recommendations and as required by procedure PLP-018, "Quality Assurance Program for Non-Safety

Systems and Equipment used to meet the Station Blackout rule" and Fire Safe Shutdown (SSD) equipment maintenance

requirements. This resulted in failure of the radiator fan belts and the automatic

shutdown of the DSDG on high engine temperature, during a surveillance test performed on October 2, 2012. The licensee corrected this condition by installing new radiator fan belts and entered the issue into their corrective action program as NCR 564838.

The inspectors determined that the failure to perform adequate preventive maintenance

on the DSDG cooling system, in accordance with vendor recommendations and as required by PLP-018, "Quality Assurance Program for Non-Safety Systems and

Equipment used to meet the Station Blackout rule" and Fire Safe Shutdown (SSD) equipment maintenance requirements was a performance deficiency (PD). This finding was more than minor because it affected the Mitigating Systems cornerstone attribute of

Equipment Performance and affected the cornerstone objective of ensuring the

availability, reliability, and capability of

systems and components that respond to initiating events to preclude undesirable consequences (i.e. core damage). Specifically, the failure to perform adequate preventive maintenance on the dedicated shutdown diesel generator (DSDG) cooling system, in accordance with vendor recommendations

resulted in the DSDG automatically shutting down on high engine temperature due to a

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Enclosure 1 failure of the radiator drive belts on October 2, 2012, during surveillance testing. The condition of the drive belts were significantly degraded due, in part, to a lack of adequate

inspection, maintenance, and/or periodic replacement, which would have rendered the

plant unable to cope for eight hours after a postulated station blackout, or provide

emergency power for certain selected Fire SSD scenarios.

Significance Determination Process (SDP) screening performed per NRC Inspection Manual Chapter (IMC) 0609.04 determined that the Performance Deficiency (PD)

affected the Mitigating Systems Cornerstone due to the Station Blackout (SBO)

mitigation function being affected and External Event Mitigation Systems were affected

due to the fire SSD function being impacted. The SDP screening determined that a detailed risk evaluation was required. A detailed SDP risk analysis was performed by a regional SRA in accordance with the guidance of NRC IMC 0609 Appendix A for the

internal events risk assessment using both the NRC H.B. Robinson SPAR model and the licensee's Robinson full scope probabilistic risk assessment (PRA) model. The

external fire risk was evaluated using the guidance of NRC IMC 0609 Appendix F and NUREG/CR 6850 revision 0 and 1 utilizing data from the licensee's National Fire Protection Association 805 project and the licensee's Robinson full scope PRA model.

The finding has external event risk which is greater than the internal risk. The internal

risk was dominated by SBO LOOP scenarios which would lead to core damage via a

loss of reactor coolant pump (RCP) seal cooling, RCP seal failure, and loss of reactor coolant system (RCS) inventory. The ex

ternal risk was dominated by fire scenarios which would result in loss of the E1 and E2 buses and result in LOSP to the DS Bus

requiring use of the DSDG for alternate shutdown per procedure DSP-002. The

dominant fire scenarios were high energy ARC fault (HEAF) scenarios in the emergency

switch gear room (ESWGR), hot gas layer scenarios in the cable spreading room (CSR) and ESWGR and a main control board fire in the main control room. The fire scenarios would lead to loss of RCP seal cooling sequences which would lead to core damage via

RCP seal failure and loss of RCS inventory. Risk increase over the base case was >1E-

6/year and <1E-5/year including internal event risk and the risk of selected fire

scenarios. The NRC concluded that the significanc

e of the finding is preliminarily low to moderate safety significance (White).

The inspectors determined that no cross cutting aspect was applicable to this

performance deficiency because the licensee has failed to perform adequate

preventative maintenance since the belts were installed in 2003 and this finding was not

indicative of current licensee performance. (Section 1R12)

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Enclosure 1 REPORT DETAILS

1. REACTOR SAFETY

Cornerstones: Initiating Events, Mitigating Systems, and Barrier Integrity

1R12 Maintenance Effectiveness

.1 (Closed) Unresolved item (URI): Adequacy of Preventative Maintenance on the

Dedicated Shutdown Diesel Generator Cooling System

a. Inspection Scope

The inspectors reviewed the licensee's Root Cause Evaluation (RCE) regarding the trip

of the Dedicated Shutdown Diesel Generator, on October 2, 2012, during monthly

surveillance testing.

b. Findings

Introduction: An Apparent Violation (AV) of 10 CFR 50.63, "Loss of All Alternating Current Power", was identified for the licensee's failure to perform adequate preventive

maintenance on the dedicated shutdown diesel generator (DSDG) cooling system, in

accordance with vendor recommendations and as required by procedure PLP-018, "Quality Assurance Program for Non-Safety

Systems and Equipment used to meet the Station Blackout rule" and Fire Safe Shutdown (SSD) equipment maintenance

requirements. This resulted in failure of the radiator fan belts and the automatic

shutdown of the DSDG on high engine temperature, during a surveillance test performed

on October 2, 2012.

Description: On October 2, 2012, during monthly testing of the DSDG, in accordance with OST-910, "Dedicated Shutdown Diesel Generator (Monthly)," the control room

received a "DSDG Trouble" alarm. Shortly after the alarm was received, the DSDG

tripped. The licensee determined that the DSDG automatically shutdown on high engine

temperature. After the trip, the diesel

was inspected and the licensee discovered that the radiator drive belts were not attached to their respective pulleys. The fan belts were replaced and the DSDG was returned to service on October 3, 2012. The licensee

initiated a root cause investigation to determine the cause of the fan belt failure.

The licensee's root cause evaluation (RCE) documented that all three drive belts had varying degrees of wear and degradation. The mode of failure was that the belts were thrown from their pulleys during operation. The analysis noted a complete loss of the

belts outer rubber fabric and pitting on the belt pulleys. Based on a historical look at

fan/motor vibration data and the material condition of the belts and motor pulleys, the

analysis concluded that the belts had been slowly degrading for the last few years.

Further, the wear observed on the belts could be attributed to improper tensioning of the fan belts which was further exacerbated by pitting on the fan pulleys. The licensee's

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Enclosure 1 preventative maintenance for the radiator fan includes a 2 year inspection of the DSDG radiator fan in accordance with PM-MDSD-FAN-001, "Cooling Tower Fan Inspection,"

Rev. 0 and a 4 year alignment and inspection of the radiator fan in accordance with CM-

608, "Alignment and Adjustment of Belt Driven Equipment," Rev 15. The inspectors

noted that the licensee's preventative maintenance (PM) program for the DSDG radiator

fans relied primarily on visual inspections and did not require the use of quantitative criteria for determining belt wear. The failed belts were originally installed in 2003. All inspections, conducted since installation, were found to be satisfactory and did not

identify any signs of degradation. The last visual inspection of the fan belts was

September 12, 2011, and the last satisfactory surveillance run was performed on August

28, 2012.

The DSDG was not available to supply back-up power, if required, from August 28, 2012 until the belts were replaced on October 3, 2012. The DSDG serves as an alternative

AC power source for plant shutdown loads under Station Blackout and Appendix R

scenarios. Based on, 8S19-P-101, RNP Station Blackout Coping Analysis Report, Robinson is required to cope for 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> after a station blackout. The licensee's UFSAR, Rev.18, Section 1.8, conformance to NRC Regulatory Guides (RG), states that

the licensee will comply with the intent of RG 1.155, Station Blackout. RG 1.155, states,

in part, that inspections, tests, administrative controls, and training necessary for

compliance with 50.63 should be prescribed by documented instructions, procedures,

and drawings and should be accomplished in ac

cordance with these documents. PLP-

018, "Quality Assurance Program for Non-Safety Systems and Equipment Used to Meet the Station Blackout Rule," states that the "DSDG shall be inspected in accordance with

vendor recommended maintenance guidelines." The fan belt manufacturer recommends

the use of a belt gauge during inspections of the belts and pulleys. However, CM-608

"Alignment and Adjustment of Belt Driven Equipment," gives mechanics the option to use a belt gauge with a quantitative criteria value of 1/32 inch wear. Based on a document review of past inspections and interviews with maintenance staff, the RCE

determined that the gauge was not typically used. In addition the RCE identified that the

criteria for visual inspections was inconsistent among the radiator PM procedures and lacked specific criteria. The evaluation also noted that another contributor to belt failure

could be age degradation. The licensee's evaluation documented that the root cause of the issue was the lack of a time-based replacement for the fan belts. The belts had been in-service since 2003 and the recommended shelf life is 6-8 years. The licensee has initiated corrective actions to revise their PM procedures to include quantitative

inspection criteria and require the use of a belt gauge during belt and pulley inspections.

Additionally, the licensee has established a PM to replace the fan belts every 4 years.

The inspectors found that the vendor recommended service life is 3 to 5 years if

maintained in accordance with the vendor recommended preventative maintenance

guidelines. The fan belt vendor maintenance guidelines included a recommendation to

inspect belts, pulleys, check for vibration, bearings, belt cover, alignment, wear, and

tension of the radiator fan belts at a 3 to 6 month interval. These belts were in service since 2003.

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Enclosure 1

Analysis: The inspectors determined that the failure to perform adequate preventive maintenance on the DSDG cooling system, in accordance with vendor recommendations

and as required by PLP-018, "Quality Assurance Program for Non-Safety Systems and Equipment used to meet the Station Blackout rule" and Fire Safe Shutdown (SSD)

equipment maintenance requirements was a performance deficiency (PD). This finding

was more than minor because it affected the Mitigating Systems cornerstone attribute of Equipment Performance and affected the cornerstone objective of ensuring the availability, reliability, and capability of

systems and components that respond to initiating events to preclude undesirable consequences (i.e. core damage). Specifically,

the failure to perform adequate preventive maintenance on the dedicated shutdown

diesel generator (DSDG) cooling system, in accordance with vendor recommendations resulted in the DSDG automatically shutting down on high engine temperature due to a failure of the radiator drive belts on October 2, 2012, during surveillance testing. The

condition of the drive belts were significantly degraded, due in part to a lack of adequate

inspection, maintenance, and/or periodic replacement, which would have rendered the

plant unable to cope for eight hours after a postulated station blackout, or provide emergency power for certain selected Fire SSD scenarios.

Significance Determination Process (SDP) screening performed per NRC Inspection

Manual Chapter (IMC) 0609.04 determined that the PD affected the Mitigating Systems

Cornerstone due to the Station Blackout (SBO) mitigation function being affected and

External Event Mitigation Systems were affected due to the fire SSD function being impacted. The SDP screening determined that a detailed risk evaluation was required. A detailed SDP risk analysis was performed by a regional SRA in accordance with the

guidance of NRC IMC 0609 Appendix A for the internal events risk assessment using

both the NRC H.B. Robinson SPAR model and the licensee's Robinson full scope

probabilistic risk assessment (PRA) model. The external fire risk was evaluated using

the guidance of NRC IMC 0609 Appendix F and NUREG/CR 6850 revision 0 and 1 utilizing data from the licensee's National Fire Protection Association 805 project and the

licensee's Robinson full scope PRA model.

The major analysis assumptions included:

• A 36 day exposure period;

• The DSDG was assumed to trip on high temperature in approximately 10 minutes after an automatic or manual start and its radiator fan drive would not cycle off for the duration of its SBO or SSD mission time;

• E1 to E2 cross-tie Bus Duct was not in service during the exposure period;

• Recovery was performed as a sensitivity analysis as licensee estimated 2.5 - 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> for radiator fan belt replacement under SBO conditions, final best risk estimate did not credit recovery;

• Fire induced damage to cable tray R85 in ESWGR would result in spurious opening of breaker 52-16B and loss of control power to 480V E2 breakers;

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Enclosure 1

• 480V Switchgear E1 HEAF zone of influence (ZOI) contains tray R85 and E1 HEAF would cause non-recoverable damage to E1; and

• 480V Switchgear E1 Offsite feeder bus duct HEAF ZOI contains tray R85 and R65 and this bus duct HEAF would cause LOSP to DS Bus and loss of control power to

E1 and E2.

The finding has external event risk which is greater than the internal risk. The internal

risk was dominated by SBO LOOP scenarios which would lead to core damage via a

loss of RCP seal cooling, RCP seal failure, and loss of RCS inventory. The external risk was dominated by fire scenarios which would result in loss of the E1 and E2 buses and result in LOSP to the DS Bus requiring use of the DSDG for alternate shutdown per

procedure DSP-002. The dominant fire scenarios were HEAF scenarios in the ESWGR,

hot gas layer scenarios in the CSR and ESWGR and a main control board fire in the

main control room. The fire scenarios would lead to loss of RCP seal cooling sequences

which would lead to core damage via RCP seal failure and loss of RCS inventory. Risk increase over the base case was >1E-6/year and <1E-5/year including internal event risk and the risk of selected fire scenarios. The

NRC concluded that the significance of the finding is preliminarily low to moderate safety significance (White).

The inspectors determined that no cross cutting aspect was applicable to this performance deficiency because the licensee has failed to perform adequate preventative maintenance since the belts were installed in 2003 and this finding was not

indicative of current licensee performance.

Enforcement: 10 CFR 50.63 (c)(2), states, in part, that the alternate ac power source, as defined in section 50.2, will constitute acceptable capability to withstand station blackout provided an analysis is performed which demonstrates that the plant has this capability from onset of the station blackout until the alternate ac source(s) and required shutdown

equipment are started and lined up to operate. Robinson Nuclear Plant Station Blackout

Coping Analysis Report 8S19-P-101, identifies the DSDG as its alternate ac power source and specifies that Robinson is required to cope for eight hours after a station blackout or provide emergency power for certain selected Fire Safe Shutdown (SSD) scenarios.

Contrary to the above, from August 28, 2012, to October 3, 2012, the licensee's

accepted alternate ac power source lacked the capability to withstand station blackout

for the required durations specified in its coping analysis. Specifically, during surveillance testing of the DSDG on October 2, 2012, the DSDG automatically shut down on high engine temperature due to a failure of the radiator drive belts. The

condition of the drive belts was significantly degraded due, in part, to a lack of adequate

inspection, maintenance, and/or periodic replacement, which would have rendered the

plant unable to cope for eight hours after a postulated station blackout or provide emergency power for certain selected Fire Safe Shutdown (SSD) scenarios. As a result, belt degradation went undetected and during surveillance testing of the DSDG on

October 2, 2012, the DSDG automatically shut down on high engine temperature due to

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Enclosure 1 a failure of the radiator fan drive belts. Following the shutdown, the licensee corrected this condition by installing new radiator fan belts and entered the issue into their

corrective action program as NCR 564838. This apparent violation is identified as AV 05000261/2013008-01, Failure to Perform Adequate Preventative Maintenance on the

DSDG In accordance with Vendor Guidelines.

4OA6 Management Meetings

1. Exit Meeting Summary

On May 22, 2013, and June 25, 2013, the resident inspectors presented the inspection results to Mr. Gideon and other members of the licensee staff. The inspectors confirmed that proprietary information was not provided or examined during the inspection period.

ATTACHMENT: SUPPLEMENTAL INFORMATION

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Attachment SUPPLEMENTAL INFORMATION

KEY POINTS OF CONTACT

Licensee Personnel

T. Cosgrove, Plant General Manager

H. Curry, Training Manager

D. Douglas, Maintenance Manager

C. Freligh, Nuclear Oversight Manager

R. Gideon, Vice President

M. Glover, Director - Site Operations R. Hightower, Licensing/Reg. Programs Supervisor

K. Holbrook, Operations Manager

B. Houston, Radiation Protection Superintendent

L. Martin, Engineering Director

K. Moser, Outage & Scheduling Manager J. Rotchford Jr., Environmental & Chemistry Superintendent

S. Wheeler, Support Services Manager

NRC Personnel

G. Hopper, Region II, Chief Reactor Projects Branch 4

LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED

Opened 05000261/2013008-01 AV Failure to Perform Adequate Preventative Maintenance

on the DSDG In accordance with Vendor Guidelines

(Section 1R12)

Closed 05000261/2012005-01 URI Adequacy of Preventative Maintenance on the

Dedicated Shutdown Diesel Generator Cooling System)

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Attachment LIST OF DOCUMENTS REVIEWED

Section 1R12: Maintenance Effectiveness

Procedures

PLP-018, Quality Assurance Program for Non-Safety Related Systems and Equipment Used to Meet the Station Blackout Rule, Rev.17 CM-608, Alignment and Adjustment of Belt Driven Equipment, Rev.16 CM-608, Alignment and Adjustment of Belt Driven Equipment, Rev. 015

OST-910, Dedicated Shutdown Diesel Generator (Monthly), Rev. 52

PM-108, Dedicated Shutdown Diesel Tent Four Month Inspection, Rev. 32

APP-025, Dedicated Shutdown Diesel Generator Annunciator Panel, Rev. 10

ADM-NGGC-0203, Preventive Maintenance and Surveillance Testing Program, Rev. 18 DSP-001, Alternative Shutdown Diagnostic, Rev.13

DSP-002, Hot Shutdown Using the Dedicated /Alternative Shutdown System, Rev. 27 PM-M-DSD-Fan-001, DSD Cooling Tower Fan-001, Rev. 0

Work Orders

1692322-01

1155184-01

1070719-01

803609-01

875542-01

804624-01

717710-01

AR's RCE 564838, DSDG Trip on High Engine Coolant Temperature 574123, RCE AR 564838 Extended Beyond 45 Days 209184, Unanticipated LCO 3.7.9 Entry Due to Degraded Belt on HVA-1B

591614, Clarification of Guidance for Transitioning to DSP-002

Miscellaneous

ME00197R12, Material Evaluation-Shelf Life Requirements, Nov. 6, 2008 Gates Belt Drive Preventive Maintenance and Safety Manual, 2004 ESI-EMD Owners Group, Recommended Maintenance Program-Mechanical, Revision 6, May

2011

Gates Facts Technical Information Library, Tips on Selecting and Applying Drive Belts, March,

1993 Enelco Industrial Fans, Service Manual Installation Operation and Maintenance Gates Industrial Belt and Drive Preventive Maintenance, 2009