ML18139B701

Application to Amend Licenses DPR-32 & DPR-37,changing Tech Spec Sections 3.22,3.23,4.12 & 4.20 Re Auxiliary Ventilation Exhaust Filter Trains & Control & Relay Room Air Filtration Sys.Resubmitted in Response to NRC 811228 Request

ML18139B701
Person / Time
Site:	Surry
Issue date:	02/03/1982
From:	Leasburg R VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	Harold Denton, Varga S Office of Nuclear Reactor Regulation
Shared Package
ML18139B702	List: ML18139B701 ML18139B703
References
016, 16, NUDOCS 8202040265
Download: ML18139B701 (2)

Text

• e VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND.., VIRGINlA 23261 R.H.LEASBURG VICE PRESIDENT NUCLEAR 0:PERATIONS Mr. Harold R. Denton, Director Serial No.

Office of Nuclear Reactor Regulation NO/RCC:lms Attn: Mr. Steven A. Varga, Chief Docket Nos. 50-280 Operating Reactors Branch No. 1 50-281 Division of Licensing License Nos. DPR-32 U. S, Nuclear Regulatory Commission DPR-37 Washington, D. C. 20555 Gentlemen:

AUXILIARY VENTILATION SYSTEM MODIFICATION PROPOSED TECHNICAL SPECIFICATIONS SURRY POWER STATION - UNITS 1 AND 2 In response to your letter Serial No. 712 dated December 28, 1981. We are enclosing a resubmittal of Technical Specifications for the Auxiliary Ventila-tion System and Control Room Air Filtration System revised to incorporate the*

items which were discussed and agreed upon on December 23, 1981.

We find that most of your comments have been resolved. Two items which remain unresolved are the acceptance criteria for the laboratory testing of used charcoal and the flow rates 6f the Control Room Air Filtration System.

With respect to the acceptance value for the efficiency of used charcoal (changeout efficiency) we find that we must use 95% in order to prevent degradation of the redundancy of this safety-related system by frequent*

replacement and in-place testing of charcoal. Since the LOCA dose analysis took credit for 90% iodine removal efficiency, the use of 95% chan:geoti.t efficiency equates to a factor of safety of 2 which we do not believe to be an uncommon design basis for nuclear plants of the Surry vintage. R*eview of existing dose analysis shows that the use of 85% charcoal efficiency would result in control room doses greater than GDC 19 limits. Furthermore, the test conditions, and particularly the 80% relative humidity we are proposing to use during laboratory analysis, equal or exceed the calculated conditions of the ventilation system. The standard test conditions from ASTM D3803 far exceed the ventilation system requirements and their use during laboratory analysis unnecessarily penalizes the ventilation system. The standard is being invoked :principally for defining the method of testing. The standard itself suggests via footnote A of Table 1, the substitution of specific operating conditions when they substantially deviate from the standardized table values.

• In summary we must emphasize that the proposed acceptance value (i.e., 95%)

Ar;6) for changeout efficiency and the test conditions for its determination in the laboratory are in accordance with the intent of the model Technical Specifi-1/(

cation enclosed in your transmittal 373/121274 and again referred to in the 18 questions enclosed in your transmittal 045/020177. Indeed the scope of the upgrading and modification work as descibed in our transmittal of August 9, 1979 were essentially determined by the content and implications of these documents.

8202040265 820203 PDR ADOCK 05000280

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VIRGINIA ELECTRIC AND POWER COMPANY TO 2 With respect to the Control Room Air Filtration System fan flow rate, we are specifying a range of flow rates rather than a single value with a+/- 10% tole-rance as you have indicated. We* have performed analyses which show that a minimum flow of 750 cfm and a maximum flow of 1100 cfm per fan would result in control room doses within the limits of GDC 19. Unlike the Auxiliary Ventila-tion System where fan capacity is regulated by sophisticated volumetric controls to maintain constant system flow rates, the Control Room and Relay Room Filtration System is of the conventional design with no capacity regula-tion. Such a design produces a decrease in system flow rate as system (filter) resistance increases. Therefore, the specification of a flow range rather than a single flow value is consistent with your allowance of a changeout filter pressure drop of 5" water gauge. DOP and halogen leakage testing may still be conducted at flow rates within the specified range. Test results are unaffected by the absolute value of the flow rate since leakage is simply determined on a percentage basis.

We trust 'that you will find the resolution of your comments and the technical basis offered for the two instances discussed in detail acceptable; if not, we would be glad to discuss these items with your staff at your earliest convenience.

We would also like to inform you that we are proceeding with adapting the format of these Technical Specifications into the format presently being used for Surry. We should also point out that our submittal is in the form of a "Draft" Technical Specification in lieu of a final submittal. In regard to the items under discussion, we feel that a "Draft" review is warranted in order to speed up a resolution to your comments. Upon your approval, we will submit Final Technical Specifications within 30 days.

If you have any questions or require additional information, please contact us.

Very truly yours, LJ\._~

~ R~ H. Leasburg Enclosure cc: Mr. James P. O'Reilly, Regional Administrator Office of Inspection and Enforcement Region II