ML20206H022

Informs That Licensee Changes Bases for TS 3/4.6.1.2, Containment Leakage. Changes Allow Use of Other NRC Staff Approved/Endorsed Integrated Leak Test Methodologies to Perform Containment Leakage Rate Testing.Ts Bases Page,Encl

ML20206H022
Person / Time
Site:	North Anna
Issue date:	05/03/1999
From:	Christian D VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20206H026	List: ML20206H022 ML20206H030
References
99-262, NUDOCS 9905110013
Download: ML20206H022 (8)

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YIRGINI A ISIECTRIC AND I'OWER CONWANY Racissu:Ni>, Vinoisir 2326:

May 3, 1999 U.S. Nuclear Regulatory Commission Serial No.99-262 Attention: Document Control Desk NL&OS/GSS/ETS R0 Washington, D.C. 20555 Docket Nos.

50-338 50-339 License Nos. NPF-4 NPF-7 Gentlemen:

VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNITS 1 AND 2 TECHNICAL SPECIFICATION BASES CHANGE 10CFR50 APPENDIX J, OPTION B LEAKAGE-RATE TESTING METHODOLOGIF)

Virginia Electric and Power Company has changed the Bases for Technical Specifications 3/4.6.1.2 " Containment Leakage." These changes are being made to allow the use of other NRC staff approved / endorsed integrated leak test methodologies to perform containment leakage rate testing. Therefore, we are providing the following Technical Specification Bases changes to the containment leakage testing methodologies for your information.

The Technical Specifications Bases changes have been reviewed and app oved by the Station Nuclear Safety and Operating Committee and the Management Safety Review Committee. It has been determined that these changes do not involve an unreviewed safety question as defined in 10 CFR 50.59.

A discussion and the Technical Specifications Bases changes are provided in Attachments 1 and 2 respectively.

If you have any further questions, please contact us.

Very truly yours, t

?, j. J I O D. A. Christian Vice President-Nuclear Operations 7

Corrmitments made in this letter:

1.

There are no comm"ments in this letter 9905110013 990503 PDR ADOCK 05000330 P

PDR

Attachments 1.

Discussion of Changes 2.

Technical Specifications Bases Changes cc:

U.S. Nuclear Regulatory Commission Region II Atlanta Fed.srul Center 61 Forsyth Street, SW Suite 23785 Atlanta, Georgia 30303 Mr. M. J. Morgan NRC Senior Resident inspector North Anna Power Station Commissioner Department of Radiological Health Room 104A 1500 East Main Street Richmond, Virginia 23219 Mr. J. E. Reasor Old Dominion Electric Cooperative innsbrook Corporate Center 4201 Dominion Blvd.

Glen Allen, Virginia 23060 I

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COMMONWEALTH OF VIRGINIA

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COUNTY OF HENRICO

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The foregoing document was acknowledged before me, in and for ti e County i

and Commonwealth aforesaid, today by D. A. Christian, who is Vice President -

Nuclear Operations, of Virginia Electric and Power Company. He has affirmed before me that he is duly authorized to execute and file the foregoing document in behalf of that Company, and that the statements in the document are true to 1

the best of his knowledge and belief.

Acknowledged before me this 3 day of ObV

,19h.

My Commission Expires: March 31,2000.

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[ JY Notary Public l

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L(SEAL)

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l Discussion of Changes Noeth Anna Power Station Units 1 and 2 Virginia Electric and Power Company

1 DISCUSSION OF CHANGE Introduction The Nuclear Regulatory Commission amended 10 CFR 50 Appendix J, " Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors" on October 26,1995, to provide a performance-based option, Option B, for leakage-rate testing requirements. By letter dated November 20,1995, as supplemented by letter dated January 23,1996, Virginia Electric and Power Company submitted proposed changes to the Technical Specifications (TS) for the North Anna Power Station, Units 1 and 2.

These changes were approved by the NRC in letter dated February 9,1996, " North Anna Units 1 and 2 -Issuance of Amendments Re: 10 CFR 50 Appendix J, Option B" and incorporated into the North Anna Units 1 and 2 Technical Specifications as Amendments 196 and 177, respectively. The changes permitted the use of Option B

" Performance-Based Requirements" to 10 CFR Part 50, Appendix J.

At that time, we chose not to identify a specific performance testing program in the Technical Specifications as an administrative program or include a discussion of the performance-based testing option in the Bases of the Technical Specifications. Since that time, we have evaluated other NRC approved / endorsed Type A test methodologies which permit significant improvement in the time required to perform a Type A test.

Therefore, we are changing the Techn. cal Specifications Bases to eliminate the specific reference to the mass-point (Type A test) method included in ANSl/ANI 56.8-1087, and ir.cluding a discussion of performance-based testing in accordance with Option B of 10 CFR Part 50, Appendix J, and Regulatory Guide 1.163 deted Septaber 1995,

" Performance-Based Containment Leak-Test Program." The Bases change permits the use of other NRC staff approved integra+ed leak rate test methodologies.

Using other NRC approved test methodologies to perform containment leakage-rate testing does not create an unreviewed safety question. The NRC approved / endorsed test methodologies provide assurance that the containment, and those systems and components which penetrate the containment, do not exceed the allowable leakage-rate values specified in the Technical Specifications and Bases.

Therefore, an unreviewed safety question is not created by this Technical Specification Bases change.

_ Background One of the conditions required of all operating licenses as specified in 10 CFR 50.54(o) is that primary reactor containments meet the leakage-rate test requirements in either Options A or B of Appendix J to 10 CFR 50. These test requirements ensure that (a) leakage through those containments or systems and components penetrating these containments does not exceed the allowable leakage rates specified in the Technical i

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4 Specifications and (b) integrity of the containment structure is maintained during its service life. Option B identifies the performance-based requirements and criteria for preoperational and subsequent periodic leakage-rate testing.

Section I, " Introduction" of 10 CFR 50 Appendix J states that specific guidance concerning a performance-based leakage-test program, acceptable leakage-rate methods, procedures, and analyses that may be used to implement these requirements and criteria are provided in Regulatory Guide 1.163.

Discussion Compliance with 10 CFR 50, Appendix J provides assurance that the primary containment, and those systems and components that penetrate the primary containment, do not exceed the allowable leakage-rate values specified in the Technical Specifications. On September 12,1995, the NRC approved the issuance of a revision to 10 CFR Part 50, Appendix J, which was subsequently published in the Federal Register on September 26,1995, and became effective on October 26,1995.

The revision added Option B, " Performance-Based Requirements" to Appendix J to allow licensees to voluntarily replace the prescriptive testing requirements of Appendix J with testing requirements based on both overall and individual component leakage-rate performance. Regulatory Guide 1.163 dated September 1995 was developed as a method acceptable to the NRC staff for implementing Option B. This regulatory guide states that the Nuclear Energy institute (NEI) document NEl 94-01, " Industry Guideline for implementing Performance-Based Option of 10 CFR Part 50, Appendix J," Revision 0, dated July 26,1995, provides methods acceptable to the NRC staff for complying with Option B.

The initial Technical Specifications changes replaced specific surveillance requirements related to primary containment leakage-rate testing (Type A) and the corresponding acceptance criteria with the requirement to perform the required leakage-rate testing in accordance with 10 CFR Part 50 Appendix J, Option B, as modified by approved exemptions and Regulatory Guide 1.163, September 1995. However, the reference to a specific testing methodology for the Type A test in the Technical Specifications Basis, Section 3/4.6.1.2 was not modified at that time. Consistent with the approved Technical Specification Amendments 196 and 177 and to permit the use of additional NRC approved testing methodologies, we are changing the Technical Specifications Bases to eliminate the specific reference to the mass-point (Type A test) method included in ANSI /ANI 56.8-1987, and including a discussion of performance-based testing in accordance with 10 CFR Part 50 Appendix J, Option B, and Regulatory Guide 1.163, September 1995.

This Basis change will permit the use of other NRC staff approved / endorsed integrated leak rate test methodologies to perform containment leakage-rate testing.

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I Specific Changes The second paragraph of Basis Section 3/4.6.1.2 CONTAINMENT LEAKAGE for Units 1 and 2 currently states:

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"The surveillance testing for measuring leakage rates are consistent with the requirements of Appendix "J" of 10 CFR 50. Due to the increased accuracy of the mass-point method for containment integrated leakage testing, the mass-point method referenced in ANSI /ANS 56.8-1987 can be used in lieu of the methods described in ANSI N45.4-1972."

The changes to the second paragraph Basis Section 3/4.6.1.2 CONTAINMENT

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LEAKAGE for Units 1 and 2 is modified as follows:

"The surveillance testing for measuring leakage rates are consistent with the l

requirements of Appendix "J" of 10 CFR 50. The containment is tested by performing leakage-rate testing as required by 10 CFR 50, Appendix J, j

Option B, as modified by approved exemptions, and in accordance with the guidelines contained in Regulatory Guide 1.163, dated September 1995 or j

other NRC approved leakage-rate testing methodologies."

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Safety Significance Using alternative NRC approved / endorsed leakage-rate test methodologies to perform the containment Type A test does not create an unreviewed safety question as described below:

I The Bases change does not increase the probability of occurrence or the j

consequences of an accident or malfunction of equipment important to safety j

previously evaluated in the safety analysis report.

l Using other approved / endorsed test methodologies does not affect the operation of the plant or generate any new methods of operation. Therefore, using other testing methodology has no impact on the probability of occurrence on any previously evaluated accident.

j The NRC approved / endorsed test methodologies adequately measure i

containment leakage to ensure tFat the primary containment, and those systems and components which penetrate the containment, do not exceed the allowable j

leakage-rate values specified in the Technical Specifications and associated Bases. The allowable leakage rate is adequately determined so that the leakage I

assumed in the safety analyses is not exceeded and the consequence of any previously identified accident or event are cot increased.

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The Bases change does not create the possibility of an accident or malfunction of a different type than any evaluated previously in the safety analysis report.

Using other NRC approved / endorsed test methodologies does not involve any physical alteration of the plant or changes in methods of operations. These testing methodologies do not impose any new plant requirements or eliminate any existing requirements. Therefore, it is concluded that no new or different kind of accident or malfunction from any previously evaluated has been created.

- The Bases change does not result in a reduction in margin of safety as defined in the basis for any Technical Specifications.

The Bases change will not reduce the margin of safety since the change has no effect on any safety analyses assumptions, lising NRC approved / endorsed test methodologies provides assurance that the containment, and those systems and components which penetrate the containment, do not exceed the allowable leakage-rate values specified in the Technical Specifications and Bases.

Therefore, the proposed changes do not result in a reduction in a margin of safety.

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