ML20140D001

Suppl to 970523 Application for Exigent Amend to License NPF-37,revising TS Surveillance Requirement Re ECCS Pump Casings & Discharge Piping High Points Outside of Containment

ML20140D001
Person / Time
Site:	Byron
Issue date:	05/31/1997
From:	Graesser K COMMONWEALTH EDISON CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20140D005	List: ML20140D001 ML20140D008
References
BYRON-97-0129, BYRON-97-129, NUDOCS 9706100185
Download: ML20140D001 (7)

Text

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If5 4 Commonwcalth Edium Company (ft - l- 11)ron Generating Mation i- ,- 460 North German Cliurcli Road fly ron,13. 610lWT'9 4

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i May 31,1997 LTR: BYRON 97-0129

_ FILE: 2.01.0301 U. S. Nuclear Regulatory Commission f Washington D.C. 20555 Attention: Document Control Desk

Subject:

Supplement to Application for EMgent Amendment to Facility Operating License Byron Station Uni! 1 Facility Operating License NPF-37

, NRC Docket No. 50-454 Emergency Core Cooling System Venting Surveillance

References:

1. Letter from G. Stanley (Comed) to NRC Document Control Desk, dated May 23,1997.

2. Letter from R. A. Capra (NRC Region III) to I.M. Johnson, " Notice of Enforcement Discretion (NOED) for Commonwealth Edison Company Regarding Byron Units 1 and 2; and Braidwood, g Unit 2," dated May 28,1997.

In Reference 1, Commonwealth Edison Co. (Comed) requested an exigent amendment for Byron Units 1 and .1 and Braidwood Units 1 and 2. The proposed change affects Technical Specification 4.5.2.b.1 with respect to venting of Emergency Core Cooling System (ECCS) pump casags and discharge piping high points outside of containment.

This was submitted as a follow-up to Reference 2.

Comed requests that the exigent amendment re: pen <a Reference 1 be approved as an emergency change for Byron Unit 1, in accordance with 10 CFR 50.91(a)(5) because an emergency situation has arisen that would prevent startup of Unit 1.10 CFR 50.91(a)(5) requires, in part, for licensees to explain why this emergency situation occurred and why g;Ol,l I it could not avoid this situation.

Unit 1 is in hot shutdown sfler cerapleting Action 22 for Technical Specif..ations Tabie

,. 3.3-3 for an inoperable channel of the steam line isolation system. While performing tht.

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scheduled quarterly partial stroke test, the active accumulator train would not l repressurize, and the channel was declared inoperable at i114 on May 29,1997. At 0303 i on May 31, the unit ramp down commenced in advance of the Technical Specin ations shutdown requirements to comply with Nuclear Operating Policy (NOP) OP-19 because the channel could not be restored to operable within the allowed time. An Emergency Notification System phone call was made at 0317. The Unit entered Mode 3 at 1458 on May 31.

l After the equipment is repaired, unit startup is precluded by failure to mer' +he ECCS i venting requirements in Technical Specification Surveillance Requirement 4.5.2.b.1. The I unit has been operating under an NOED (Reference 2). The Staff has been reviewing Comed's request for an exigent amendment (Reference 1), however, this event occurred before the Staff could complete its review of that request. Approval of the exigent i

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request (Reference 1) would have precluded the need for this emergency request. Comed anticipates that the equipment will be repaired and Unit I will be ready to commence heatup at 0000 on June 2,1997. Therefore, Comed is requesting that the pending exigent I' amendment request for Byron Unit 1 be approved as an emergency amendment request The technicaljustification for this emergency amendment request for Byron Unit 1 is identical to Attachment A of the exigent amendment request (Reference 1). Therefore, Attachment A of Reference 1 remains applicable.

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The situation could not be avoided because the rmeillance failure was unexpected, and  !

the equipment repair required more than the 484a_ c allowed action time. If the emergency request is not approved, resumption o' operation of Byron Unit 1 is not allowed. Otherwise, Unit startup would be unnecessarily precluded because Comed would need to wait two weeks for the exigent change to be approved.

The proposed changes have been reviewed and approved by the On-site and Off-site ,

Review Committees, in accordance with Comed procedures. Comed has reviewed this I proposed amendment in accordance with 10 CFR 50.92(c) and has determined +.at no significant hazards consideration exists. This is documented in Attachment A. The marked-up pages are provided in Attachment B. Comed has reviewed this request and determined that it meets the requirements of NRC Administrative Letter 95-05.

To the best of my knowledge and belief, the statements contained above are true and Co!Tect.

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Please direct any questions to Denise Saccomando, Nuclear Licensing Administrator, at (630) 663-7283.

Sincerely, l

/ 'v K.L. Graesser Site Vice President Byron Nuclear Power Station Attachments  !

cc: A. B. Beach, Regional Administrator - RIII l S. Burgess, Senior Resident Inspector - Byron G. Dick, Byron Project Manager - NRR Office of Nuclear Safety - IDNS l

Signed before me this N.N day, l

of 3 6/ 3 s. .1997, by ' M(1L W flh.L(/ '

l Notary (Public i --

NotaryPubits of M h t  : *u r w.imo l

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ATTACHMENT A l

EVALUATION OF SIGNIFICANT HAZARDS CONSIDERATION FOR PROPOSED CHANGES TO APPENDIX A, TECHNICAL SPECIFICATIONS, FOR FACILITY OPERATING LICENSE NPF-37 A. INTRODUCTION Commonwealth Edison (Comed) proposes to revise Technical Specification (TS) 4.5.2.b.1 and associated bases for Byron Unit I as they relate to the requirement to vent the Emergency Core Cooling Systems (ECCS) pump casings and discharge piping high points. The change will revise the venting requirement to l encompass the non-operating ECCS pumps and discharge piping that is provided )

with high point vent valves. Those ponions of the ECCS systems that are in communication with operating system pressure and/or flow would not be required to be vented. This would normally encompass the High Head Safety Injection

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(CV) subsystem during Modes 1-4 operation, and the Low Head Safety injection Subsystem (RH) during periods when shutdown cooling is in operation.

Additionally, the wording of the surveillance will be revised to clearly indicate l

that the installed high point vent valves and pump casing vent valves will be utilized to accomplish the venting operation. The Intermediate Head Safety Injection (SI) subsystem and the RH subsystem are equipped with pump casing vents. The centrifugal CV pumps are not equipped with pump casing vent valves due to the configuration of the suction and discharge piping. Both the suction and discharge piping enter the pump casing from the top, so the pumps are essentially self-venting. Finally, a new requirement is added to ultrasonically examine the discharge piping cDi idle centrifugal charging pump and the portion of the piping upstream C u High Head Safety injection isolation valves (ISI8801 A&B) adjacent to the vent valve ISIO45 on a monthly basii These changes are required to align the surveillance requirement with the physical construction of the installed piping, and accommodate operating conditions which preclude cycling of the installed high point vent valve during system operation.

B. NO SIGNIFICANT HAZARDS ANALYSIS Comed has evaluated this request for emergency license amendment and

'etermined that it involves no s: $ cant hazard considerations. An action is determined to involve no significa." h> zard considerations if:

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1. The proposed change does not involve a significant increase in the probability ofoccurrence or the consequences of an accident previously evaluated.

2. The proposed change does not create the possibility of a new or different kind of accident from any accident previously evaluated.

3. The proposed change does not involve a significant reduction in a margin ofsafety.

1. The proposed change does not involve a significant increase in the probability of occurrence or the consequences of an accident previously evaluated.

Comed has determined that the proposed change for relief from the surveillance  !

requirements of TS 4.5.2.b.1 for the CV system for Byron Unit I does not represent an increase in the probability or consequences of an accident. This conclusion is justified by the fact that this request does not increase the probability of an accident occurring. In addition, Comed has determined that the CV syste.n remains fully capable of performing its intended design function, including mitigation of design basis accidents. Although it has been determined that Byron is not in literal compliance with the surveillance requirements in TS 4.5.2.b.1, the functional intent of the surveillance has been met by the inherent design of the CV pumps and the configuration of system piping. This is further supported by the compensatury action to perform ultrasonic testing inspections of the vulnerable sections of CV system piping for air voids on a weekly basis. No air voids have been identified. Therefore, since the CV system is expected to function as designed; there would be no increase in consequences from that previously evaluated.

2. The proposed change does not create the possibility of a new or different kind of accident from any accident previously evaluated.

No new or different accidents are created by the proposed change. The potential for water hammer in the ECCS system piping tias been previously evaluated and found not to be a concern. In addition, Comed believes that the CV system for Byron Unit I will remain free from significant air voids. Therefore, no new or different accidents from those previously evaluated are created.

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l 3. The proposed change does not involve a significant reduction in a margin of l safety. i t

Comed has determined that, with the inherent design of the CV system, along I with the compensatory action to UT the vulnerable areas of CV system piping, the l CV system meets the intent of TS surveillance requirement 4.5.2.b.1 for ECCS ,

system venting. Therefore, since the system meets the intent of the venting '

l l surveillance, it is fully capable of performing its intended design function. No margm of safety would be reduced.

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ATTACIIMENT B l PROPOSED CIIANGES TO APPENDIX A, TECIINICAL SPECIFICATIONS, FOR FACILITY OPERATING LICENSE NPF-37 BYRON NUCLEAR POWER STATION, UNIT 1 REVISED PAGES:

3/4 5-4a (new page for Unit 1) 3/4 5-4b (applicable to Unit 2)

B 3/4 5-2 l

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