ML20237H436

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Responds to NRC 870729 & 0506 Ltrs Re Nonconformances Noted in Insp Repts 50-277/87-11 & 50-278/87-11.Corrective Actions:Separate Automatic Control Circuit Being Created in Event of App R Fire
ML20237H436
Person / Time
Site: Peach Bottom  Constellation icon.png
Issue date: 08/28/1987
From: Gallagher J
PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:
NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM), NRC OFFICE OF ENFORCEMENT (OE)
References
NUDOCS 8709030269
Download: ML20237H436 (9)


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PHILADELPHIA ELECTRIC COMPANY i l

2301 M A RK ET STR EET P.O. BOX 8699 PHILADELPHIA A, PA.19101 (21si s4iscot j do * * *,7 ;f,^,',',^,y H z a August, 28, 1987 l

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Docket Nos. 50-277 '

50-278 Director 3 Office of Enforcement j U. S. Nuclear Regulatory Commission Attn Document Control Desk Washington, DC 20555

SUBJECT:

Reply to Notice of Violation (Combined Inspection Report Nos. 50-277/87-11 and 50-278/87-11)

Dear Director:

Your letter dated July 29, 1987 transmitted the " Notice of Violation and Proposed Imposition of Civil Penalty" concerning the Combined Inspection Report 50-277/87-11 and 50-278/87-11.

This Inspection Report was previously transmitted to the Philadelphia Electric Company in a letter dated May 6, 1987.

The " Notice of Violation and Proposed Imposition of Civil Penalty" describes specific examples of the failure to satisfy the fire protection requirements of 10 CPR Part 50, Appendix R. Attached is our reply to the Notice and a check payable to the Commission in the amount of $50,000 in payment of the proposed Civil Penalty. i l

If you have any questions or require additional information, please do not hesitate to contact us.

l Very truly ;murs, 1

1 Attachments l

.cc: Addressee T. P. Johnson, Resident Site Inspector #

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8709030269 B70828 gDR ADOCK 0500 7

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Attcchm:nt A Page 1 of 7 Docket Nos. 50-277 50-278 Philadelphia Electric Company's Reply to The Notice of Violation Restatement of the Violation 10 CFR 50, Appendix R, Section III.G.1 requ.res, in part, that fire protection features shall be provided for structures, systems and components important to safe shutdown. These features shall be capable of limiting firt tiamage so that one train of systems necessary to achieve and m/.intain hot shutdown conditions from either the control room or emergency control stations is free of fire damage.

Section III.G.2 states, in part, that where cables or equipment of redundant trains of systems necessary to achieve and maintain hot shutdown conditions are located within the same fire area outside of primary containment, a means of maintaining one of the trains free of fire damage shall be provided.

Contrary to the above, the licensee identified to the NRC, in letters dated May 22, September 17, and October 31, 1986, numerous instances where cables and equipment of redundarit trains of systems necessary to achieve hot shutdown were located within the same fire area outside of primary containment, and a means of maintaining one of the trains free of fire damage was not provided.

Specific examples of these failures included the following:

1. Control power cables for the redundant Emergency Service Water Pumps A and B were located in the same fire area, Fire Area 43 for Units 2 and 3. The operation of one of these pumpn is needed for safe shutdown in that they supply service water to the diesel generators, the emergency AC power source.
2. Control power cables for the four redundant Residual Heat Removal (RHR) pumps (Nos. 2AP35, 2BP35, 2CP35 and 2DP25) were in Fire Area No. 35 of Unit 2. The operation of one of

-these pumps is needed in the Suppression Pool Cooling Mode to remove decay heat and achieve safe shutdown. ,

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3. Reactor Water Level Indicators (Nos. LI3-2-3-85A, LI3-2 l; 85B, LI3-2-3-rt5, LR3-2-3-110A, LR3-2-3-110B), Reactor Pressure Indicators (Nos. PI3-6-90A, PI3-6-90B), and Reactor Pressure Recorders (Nos. PR3-2-3-404A, PR3-2-3-404B, and l PR3-6-96) were located in fire area No. 13N of Unit 3.

These indicators and recorders are needed for the monitoring i

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Attachment A Page 2 of 7 Docket Nos. 50-277 50-278 and control of reactor water level and pressure to achieve  !

E safe shutdown. I

4. Various power, control, and indication components of the Reactor Core Isolation Cooling (RCIC) system, control cables j for the High Pressure Coolant Injection (HPCI) system, and I components for the RHR System or the Core Spray (CS) system were located in Fire Area No. 6S of Unit 2. The RCIC system, HPCI system, RHR system in the Low Pressure Coolant Injection Mode, and the Core Spray System in conjunction with the manual operation of safety relief valves, are
  • 1 needed to provide coolant makeup to the reactor to achieve safe shutdown.

) 5. The instrument air supply cooper tubing to the Safety Relief

] Valves (SRVs) and the redundant nitrogen supply copper J tubing to the SRVs were located in Fire Area No. 13S of Unit

3. The tubing is used to provide pneumatic power for manual operation of the SRVs, which in turn provides for depressurization of the reactor when needed to achieve safe shutdown.

Admission or Denial of the Violation Philadelphia Electric Company acknowledges the violation as stated.

Reason for the Violation Philadelphia Electric Company initiated a safe shutdown confirmatory review in the fall of 1985 to demonstrate our 3 compliance to Appendix R at the Peach Bottom Atomic Power Station Units 2 and 3, especially with respect to the latest Appendix R guidance. This review identified approximately 50 nonconformances based on changes in previous safe shutdown analyses assumptions, consideration of additional spurious operations, identification of oversights in the previous analyses and the inclusion of modifications required for safe and alternative shutdown that were previously identified. These nonconformances were submitted to the Nuclear Regulatory Commission in letters dated May 22, 1986, September 17, 1986 and October 31, 1986 and were discussed at a June 3, 1987 Enforcement Conference. This Notice of Violation lists five of the nonconformances identified in the letters previously forwarded to the Nuclear Regulatory Commission.

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Attachment A L Page 3 of 7 l Docket Nos. 50-277 50-278 )

Extent or Significance of the Violation The significance of the five identified nonconformances on the safe shutdown capability of Units 2 and 3 are as follows:

A. Nonconformance Items 1, 2, and 4 The rereview of the safe shutdown capability at Peach i Bottom Units 2 and 3 that began in the fall of 1985 included the guidance provided in Generic Letter 86- j

10. This guidance has been factored into the assumptions used in performing the Appendix R safe shutdown analyses. The safe shutdown analyses, performed prior to the 1985 review, assumed that hot shorts and grounds cn the ungrounded DC system will not inhibit safe shutdown. Ungrounded DC systems are now assumed to become grounded as a result of an Appendix R fire and the potential for opening of control fuses and spurious operations are included in the analyses. These assumptions lead to the failure of: a) both Emergency Service Water pumps as the result of an Appendix R fire in Fire Area 43, b) all four Unit 2 Residual Heat Removal system pumps as a result of a fire in Fire Area 35 and, c) the Unit 2 High Pressure Coolant Injection System as the result of a fire in Fire Area 6S. Failure of this equipment could result in the failure to achieve safe shutdown.

B. Nonconformance Item 3 1

Prev ous analyses assumed that sufficient station battery capacity existed to supply power to equipment e necessary to achieve Hot Shutdown in the event of an Appendix R fire. Cold Shutdown would be achieved following repairs to equipment which would restore battery charging capability. As a result of the guidance provided in Generic Letter 86-10, multiple high impedance faults in fire damaged circuits are now factored into the battery depletion calculations. The batteries will deplete at a faster rate with the largest credible high impedance fault being added to each battery capacity calculation. Consequently, a fire in Fire Area 13N will result in a faster depletion of the station battery which supplies power to the process monitoring instrumentation. The process monitoring instrumentation is needed for the monitoring of reactor water level and pressure to achieve safe shutdown.

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Attachment A Page 4 of 7 Docket Nos. 50-277 50-278 C. Nonconformance Item 5 Previous analyses assumed that Unit 2 instrument air compressors would be available to provide pneumatic power to the Unit 3 Safety Relief Valves via cross tie piping in the event of an Appendix R fire in Fire Area 13S. During the rereview in the fall of 1985, it was determined that although the Unit 2 headers to the Unit 3 Safety Relief Valves would be free from fire damage, nonisolatable parallel headers could be subjected to fire damage and subsequently result in the inability to provide pneumatic power for manual operation of the Unit 3 Safety Relief Valves. Loss of manual control of the Unit 3 Safety Relief Valves would not allow for sufficient reactor vessel depressurization to achieve Cold Shutdown.

Corrective Actions and Results Achieved Interim and permanent corrective actions for the nonconformance items have been identified in previous correspondence to the Nuclear Regulatory Commission dated November 28, 1986 and June 4, 1986. The five examples cited in the Notice of Violation are identified in the November 28, 1986 submittal as conditions I.B.1, I.B.3, I.A.1, I.B.4 and I.E. Modifications to correct the previously identified nonconformance items have either been completed or are in progress. To verify that these modifications accomplish the safe shutdown objective and that all modifications designed since the generation of the initial safe shutdown database do not degrade safe shutdown capability, the safe shutdown database and analysis have been updated for Unit 2 only. 1 This revision does not include the Unit 3 safe shutdown modifications because the Unit 3 outage is scheduled to begin in October 1987 and the Unit 3 modification designs are not complete. The Unit 3 safe shutdown modifications are evaluated {

and added in the safe shutdown database and analyses as part of I the modification process.

In respanse to the five nonconformance items identified in this Inspection Report, the corrective actions discussed below are being taken. Modifications required to bring Unit 2 into  ;

compliance with Appendix R will be completed prior to Unit 2 i startup after the current refueling outage, and modifications required to bring Unit 3 into compliance with Appendix R will be i completed prior to Unit 3 startup after the upcoming pipe )

replacement outage.

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Attachment A Page 5 of 7 Docket Nos. 50-277 50-278 l l

A. Nonconformance Item 1 A separate automatic control circuit for the Emergency Service Water pump breakers is being created by a modification that separately fuses from the main control circuit the automatic logic that starts an Emergency Service Water pump from either the low speed relays, the MCA relay, or back-up pump logic. The fuses are coordinated to open before the main control power fuses of the pump breaker. This will isolate i fire-induced faults on the automatic control circuit and allow the Emergency Service Water pump to be operated manually without loss of indication or relay protection. This modification will ensure the l availability of a Emergency tarvice Water pump in the l event of an Appendix R fire in Fire Area 43.

B. Nonconformance Item 2 Control Cable ZA2A1506J, which is required for the 2A Residual Heat Removal System pump breaker, was l encapsulated in a 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> fire barrier in Fire Area 35.

This modification provided separation for redundant Residual Heat Removal trains thus ensuring the availability of a Residual Heat Removal pump in the event of an Appendix R fire in Fire Area 35. This modification was completed January 14, 1987.

C. Nonconformance Item 3 Reactor water level indication will be ensured by the installation of a new level transmitter and the establishment of a new reactor water level loop (LI3-2-3-113) for safe shutdown. Normal power to the loop will be from Unit 3; an alternate source from Unit 2 will be available via a manual transfer switch. Power to the reactor pressure recorder (PR3-6-96) will be ensured by the installation of a manual transfer switch to provide an alternate power source from Unit i

2. This modification will ensure the availability of I sufficient process monitoring instrumentation in the event of an Appendix R fire in Fire Area 13N.

l D. Nonconformance Item 4 The high reactor water level trip units will be l relocated outside of Fire Area 6S as part of a plant l modification that adds pressure compensation to l reactor water level indication. Consequently, the I

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4 Attachment A Page 6 of 7 Docket Nos. 50-277 50-278 cable problem previously identified with a spurious and sustained trip signal to the High Pressure Coolant Injection will no longer exist. Safe shutdown will be assured through the use of the High Pressure Coolant Injection System in the event of an Appendix R fire in Fire Area 6S.

E. Nonconformance Item 5 In the event of an Appendix R fire, pneumatic power to the Sdfety Relief Valves will be ensured by the installation of a backup nitrogen supply from the Safety Grade Instrument Gas System. The backup nitrogen will be available to the Safety Relief Valves via manual operation. After the manual alignment of the backup nitrogen supply, manual control of the Unit 3 E, H, and J Safety Relief Valves will be available from the Main Plant Control Room in the event of an Appendix R fire in Fire Area 13S.

Actions to Prevent Recurrence Philadelphia Electric Company concurs with the Nuclear Regulatory Commission that the process to complete the fire protection review and implementation of the modifications at the Peach Bottom Atomic Power Station has been lengthy in reaching a resolution. Although we believe that the Philadelphia Electsic Company gave Appendix R and its impact on Peach Bottom significant management attention over the past several years and that the level of this attention increased to even a higher level upon deciding in the Fall of 1985 to perform the confirmatory review, evidently, the importance of the situation was not fully recognized.

Engineering and Research Department Procedures require completion of a Fire Protection Review Checklist for every modification. As an action to prevent recurrence, the safe shutdown portion of this checklist is supplemented by a safe shutdown evaluation form. The evaluation form is used by the Philadelphia Electric Company Engineering Department in its evaluation of the impact of the modification on the current revision of the safe shutdown database and analysis and all previous safe shutdown evaluation forms. The use of the checklist and the evaluation form ensures continued compliance to the requirements of Appendix R. The incorporation of the evaluation data into revisions of the safe shutdown database and analysis is done periodically.

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Attachment A Page 7'of 7 Docket Nos. 50-277 50-278 1

.l Date for full Compliance Modifications required to bring Unit 2 into ec.pliance with

-Appendix R will be completed prior to Unit 2 startup after the current refuelittg outage, and modifications required to bring Unit 3 into compliance with Appendix R will be completed. prior to Unit 3 startup after the upcoming pipe replacement outage. These modifications resolve all noncompliance identified by 3

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