TXX-9416, Provides Addl Info to Suppl Ltr Re Inservice Test Program

Provides Addl Info to Suppl Ltr Re Inservice Test Program

ML20072C405
Person / Time
Site:	Comanche Peak
Issue date:	08/12/1994
From:	William Cahill TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
TXX-94164, NUDOCS 9408170225
Download: ML20072C405 (3)

Text

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.""."".'"".aa, Log # TXX-94164

. _ File # 10010 i I

1 _~ 950 I

r r Ref. # 10CFR50.12(a)(2)(ii) 7UELECTRIC 10CFR50.55a(f)(4)(ii) f I

William J. Cahill, Jr.

u~, n e r,,,um August 12, 1994 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555

SUBJECT:

COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)

DOCKET N05. 50-445 AND 50-446 REQUEST FOR EXEMPTION FROM 10CFR50.55a(f)(4)(ii) FOR UNIT 1 INSERVICE TEST PROGRAM (TEST INTERVALS),

ADDITIONAL INFORMATION REF: 1) Appendix R of Supplement No. 26 to NUREG-0797, Related to the Operation of Comanche Peak Steam Electric Station, Unit 2 (February 1993)

2) NRC Letter from Suzanne C. Black to William J. Cahill, Jr.

dated January 29, 1993, " Safety Evaluation of the first ten-year interval inservice testing program for pumps and valves, Comanche Peak Steam Electric Station, Unit 1 (TAC NO. M84072)"

l 3) TV Electric Letter logged TXX-94051 from William J. Cahill, Jr. to the NRC dated March 1, 1994 Gentlemen:

In References 1 and 2, the NRC stated that if TU Electric proposed to use the Unit 2 commercial operation date for establishing the 120-month interval for both units an exemption from the regulations is required.

Pursuant to 10CFR50.12(a)(2)(ii), TU Electric requested in Reference 3 an exemption from the requirement of 10CFR50.55a(f)(4)(ii) to allow the first periodic 120-month interval for the Unit 1 Inservice Test Plan to begin on the Unit 2 commercial operation date (August 3, 1993). The first periodic interval for Unit 1 is currently based on the Unit 1 commercial operation date(August 13,1990). As a result of conversations with the NRC staff, this letter is providing additional information to supplement Reference 3.

Regulation 10CFR50.12(a)(2)(ii) allows an exemption if:

Application of the regulation in the particular circumstances would not serve the underlying purpose of the rule or is not necessary to achieve the underlying purpose of the rule l

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TXX-94164 Page 2 of 3 The underlying purpose of the rule is to assure that inservice testing programs are routinely updated to conform to advances in the industry in order to assure continued operability of pumps and valves requ % d for safe operation. At TU Electric's request, the NRC staff granted perrn,ssion to use the later approved 1989 edition of ASME Section XI for the interval of inservice testing at CPSE: Unit 2 and at the same time granted permission to update the Unit 1 Inservice Test (IST) program to the use of that same Code.

Effectively, the pumps and valves at CPSES Units 1 and 2 are being tested to the requirements of a later Code edition that might otherwise not be required to be implemented until the year 2000 for Unit 1 and the year 2003 for Unit 2. The changes to the 1989 edition of ASME Section XI regarding pump and valve testing represent a substantial technical improvement over the 1986 edition not usualh 'ound from edition to edition. Since none of the IST test frequencies are directly tied to the 120-month interval (e.g.,

"twice per 120-month interval"), the test frequencies are unchanged and remain compliant with the committed edition of the code or as modified by approved relief requests.

The proposed exemption provides a degree of IST that is equivalent to that required by 10CFR50.55a(f)(ii) such that there would be no increase in the risk of failure for operational readiness of pumps and valves whose function is required for the safety of Unit 1. Accordingly the underlying purpose of 10CFR50.55a(f)(4)(ii) would continue to be achieved. Since the Unit 1 IST was updated to the Code edition required to support the ccmmercial operation of Unit 2 on August 3, 1!93, Unit 1 was effectively updated per 10CFR50.55a(f)(4)(ii) at 'hnt time. Thus using that date as the start of the 120-month interval wil' acii ieve the underlying purpose of the rule.

Also as required by regulation 10CFR50.12(a)(1) the exemption must not present an undue risk to the public health and safety, and be consistent with the common defense and security. A significant Unit difference is eliminated by applying the same Code requirements to the testing of both units. An advantage is the reduction in the potential risk for personnel errors in the performance of testing requirements. The significant reduction in administrative effort required in reviewing and approving periodic updates would free limited resources for safety significant issues.

This exemption increases plant safety through simplification and standardization of plant testing procedures, does not present an undue risk to the public health and safety and is consistent with the commer defense and security.

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TXX-94164

• Page 3 of 3 If you have any questions please contact Mr. Carl B. Corbin at (214)812-8859.

Sincerely, William J. Cahill, Jr.

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By:

D. R. Woodlan Docket Licensing Manager CBC/bm c- Mr. L. J. Callan, Region IV Mr. Y. A. Yandell, Region IV Resident Inspectors, CPSES (2)

Mr. T. A. Bergman, NRR

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