ML19282B554

Notification of Completion of Review of Tech Specs Surveillance Requirements & Preoperational Testing Associated W/Reactor Startup.Advises That Certain Surveillance Stds Will Be Due Before Refueling Date

ML19282B554
Person / Time
Site:	North Anna
Issue date:	03/07/1979
From:	Stallings C VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	Parr O Office of Nuclear Reactor Regulation
References
120, NUDOCS 7903150351
Download: ML19282B554 (5)

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VinGINIA ELecrnic Ann Powen Cownwxv RICIIMOND,VIHOINIA u Ou 61 March 7, 1979 '

Mr. Harold R. Denton, Director Ser! ' No. 120 Office of Nuclear Reactor Regulation P0/DLu:scj Attn: Mr. O. D. Parr, Chief Docket No.: 50-338 Light Water Reactors Branch No. 3 License No.: NPF-4 Division of Project Management U. S. Nuclear Regulatory Commission Washington, D. C. 20555 s

Dear Mr. Denton:

We have recently completed a review of the Technical Specification surveillance requirements for North Anna Unit 1 and of the preoperational testing associated with the startup of that unit. It has been determined that, due to the protracted nature of the preoperational test program, certain surveillance requirements will become due for performance befare the anticipated refueling date of September, 1979.

The surveillance requirements in question fall into four categories:

1) Type B and C leakage testing, 2) reactor protection and engineered safety features response time, 3) safety injection and containment depressuri-zation actuation, and 4) instrument calibration.

North Anna Unit 1 is presently scheduled to be shutdown on March 24, 1979 for a one week snubber inspection. We have made every effort to schedule as many of the refueling surveillance requirements as possible during the snubber inspection outage. However, the performance of all such tests which are due before September, 1979 would require an extension of the outage by several weeks. Accordingly, we have evaluated the implications of deferring certain of the surveillance requirements until the September refueling. We have concluded that the deferral of a small portion of the surveillance requirements would have no significant ef fect on the ability of the plant systems to respond and perform in the event of an accident. Those surveillance items for which deferral is planned are listed in the attachment, with the dates of last performance and current due dates. Note that many of the items listed will not be late if performed by mid September, based on the 25% scheduling flexibility permitted by T.S. 4.0.2. As explained below, in certain cases, alternate or abbreviated testing will be performed. The tests for which deferral is planned represent only a small but time consuming portion of the refueling test requirements in each category. We request your approval of the deferral of those items listed in the attachment. It is further requested that the 25% scheduling allowance permitted by Technical Specification 4.0.2 be considered not to have been used in the deferral process and therefore not applicable to the combined interval limits of T.S.

This will allow flexibility in the scheduling of surveillance 4.0.2.b.

testing after the first refueling. b(3 790315035sl

v,wisia EucTMIC AMD POWEN tOMPm TO Mr. Harold R. Denton 2 Following, for each of the four test categories, are discussions of the implications of test deferral and, where ann 1.icable, explanations of alternate testing to be performed.

1) Type B & C Testing The Type B and C leakage tests completed prior to unit startup demonstrated that the North Anna Unit 1 containment was exceptionally leak tight. The total Type B and C leakage was 384.34 SCFD with 110.74 SCFD from Type B and 273.6 SCFD from Type C. This total was less than 9% of the allowable limit of 4395.0 SCFD.

To demonstrate that the North Anna Unit 1 containment remains satisfactorily leak tight we intend to perform an abbreviated Type C leak test during the snubber inspection outage. The purpose of the abbreviated test will be to determine, based on a sampling of penetrations, if Type C leak tightness has deteriorated significantly since the preoperational tests. The sample of penetrations to be tested will include all penetrations which leaked at a rate greater than 6 SCFD during the initial testing. This sampling criteria includes all penetra-tions which leaked at even a moderate rate during initial testing.

During the initial Type C tests, the proposed sample contributed 85% of the total leak rate. This approach will prevent a 3 to 4 week outage extension by deferring the testing of the large majority of valves which showed zero or negligible leakage during the initial tests.

The test of the sample penetrations will be in accordance with established Type C testing procedures. A new total leakage for the sample group will be determined. The total leakage for the sample will be divided by the initial Type C test total for the sample to yield a ratio, "R", representative of the degree of leakage increase. The total initial Type C leakage will then be multiplied by "R" to determine an estimated current total leakage. If the estimated current Type C leakage is greater than 3077 SCFD (70% of the limit), the leakage testing program will be expanded to include the entire Type C test program.

Regarding Type B testing, the initial Type B total was only 2.5%

of the limit. The only Type B penetration which has been disturbed since the initial test are the personnel hatches, which are tested in accordance with T.S. 4.6.1.3. Due to their outstanding performance to date and the nearly new condition of the penetration seals, we have concluded that the deterioration of the Type B penetrations has been negligible.

We consider the abbreviated Type C test program to be a prudent and conservative means to assure containment integrity and more than adequate justification for deferral of a portion of the leakage testing requirements for three months.

Vinoisir Eucraic no Powra Cowersy To Mr. Harold R. Denton 3

2) Reactor Protection and Engineered Safety Features Response Times Technical Specifications require that one train and a fraction of the number of channels be tested every 18 months such that response times of both logic trains of the Reactor Protection and Engineered Safeguards Features (ESF) systems are measured every 36 months. As part of the preoperational test program, both trains and all channels of protection and ESF junctions were checked and found to be in tolerance (typically 10-40% below limits).

We intend to test both trains and all channels of protection and ESF functions during the September refueling. This exceeds the requirement of testing each train every 36 months. The rotating test sequence permitted by Technical Specifications will be followed in subsequent refuelings. Since most of the extensions requested are short compared to the allowable 36 months, and in view of the comprehensive testing to be performed during the first refueling, we consider the short extensions to be justified.

3) Safety Injection and Containment Depressurization Actuation The tests in this category involve cycling of valves and energizing pumps in response to test signals. Each of the valves and pumps responded satisfactorily to test signals during preoperational testing. Pursuant to T.S. 4.0.5. many of the valves and all of the pumps involved are functionally tested on a greater frequency than 18 months to assure operability. In addition, the reactor trip and ESF Actuation System logic is tested monthly in accordance with T.S. 4.3.1.1.2 and 4.3.2.1.2.

Based on this information and the fact that the average extension is only about I week, the deferral of these tests is considered reasonable.

The list also includes station blackout functions. It was demonstrat-ed that the diesel generator would start from ambient conditiot,s and pick up the bus from blackout conditions during unit startup procedures in May 1978. This test functionally tested many of the time delay relays and some of the ESF equipment (charging pumps). In additon, the diesel is full load tested monthly to verify operability. We therefore consider diesel operability during a station blackout to have been sufficiently demonstrated such that these tests can be deferred until the refueling outage.

vinomA Euctuic AND POWEk COMPANY To Mr. Harold R. Denton 4

4) Instrument Calibration The two instrument calibration items include calibration of the station reserve under voltage relays and of the seismic instrumentation.

In the case of the UV relays the calibration can probably be completed by 9/13/79, within the allowable extension of 25%. Thus, for the UV relays we are requesting only that the 25% allowance be considered non-cumulative for this extension.

The calibration of the scismic instrumentation is performed by a consultant. While we are attempting to arrange for the performance of these calibrations during the snubber inspection outage, this may not be possible. We do not believe that an extension of approximately 3 months will affect the ability of these instruments to perform their intended function. We have made every ef fort to schedule as many of the refueling surveillance requirements as possible during the snubber inspection outage. We will perform an abbreviated Type C leakage test to verify containment integrity.

As summarized above, the deferral of these few surveillance requirerents will have no significant effect on the ability of the systems to respond and perform under accident conditions. Accordingly, an extension of the upcoming outage by several weeks in order to perform these test would result in significant expense and use of alternate fuels with no commensurate benefits.

Your timely response to this request vould be greatly appreciated.

Very truly yours, Y

C. M. Stallings Vice President-Power Supply and Production Operations

ATTACIDIENT

1) Type B and C Testing T.S. LAST DONE 24M

4. 6.1. 2.d (Type B) 6/28/77 6/28/79 (Type C) 6/6/77 6/6/79

2) Time Response Testing T.S. LAST DONE 18M DATE 18M + 25% DATE

4. 3.1.1. 3 (Sensors) 10/11/77 4/11/79 8/26/79 (Circuit) 10/13/77 4/13/79 8/28/79 (Slave Relays) 10/19/77 4/19/79 9/4/79 (UV Coil) 12/15/77 6/15/79 11/1/79 4.3.2.1.3 (Turb-Reactor) 11/2/77 5/2/79 9/17/79

3) Safety Inj ec tion, Containment Depressurization Actuat, Station Blackout T.S. LAST DONE 18M DATE 18M + 25% DATE

4. 6. 2.1. C 10/25/77 4/25/79 9/10/79

4. 6. 2. 2.1. C 10/25/77 4/25/79 9/10/79 4.6.2.3.C 10/25/77 4/25/79 9/10/79 4.6.3.1.2.a 10/20/77 4/20/79 9/5/79 4.'.3.1.2.b 10/25/77 4/25/79 9/10/79 4.7.4.1.d.2 10/25/77 4/25/79 9/10/79

4. 7. 8.1. d . 2 10/25/77 4/25/79 9/10/79 4.7.1.2.b.2 10/25/77 4/25/79 9/10/79 4.8.1.1.2.C.2 .6 6/30/77 12/30/78 4/15/79

4) Instrument Calibrations T.S. LAST DONE 18M DATE 18M + 25% DATE 4.3.2.1.1 (Channel 10/28/77 4/28/79 9/13/79 Cal. item 6C) 4.3.3.3.1 7/12/77 1/12/79 5/27/79