ML20203N806
| ML20203N806 | |
| Person / Time | |
|---|---|
| Site: | McGuire, Mcguire  |
| Issue date: | 10/09/1986 |
| From: | Tucker H DUKE POWER CO. |
| To: | Harold Denton, Youngblood B Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20203N808 | List: |
| References | |
| NUDOCS 8610200037 | |
| Download: ML20203N806 (3) | |
Text
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e DUKE POWER GOMPANY P.O. HOX 33180 011AHLOrn!, N.C. 28242 HALILTIJGKER retzenoxe mm raronorwr (704) 373-4538 wiu aAsemoner m m October 9, 1986 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U.S. Nuclear Regulntory Commission Washington, D.C.
205S5 ATTENTION:
B.J. Youngblood, Director PWR Project Directorate #4
Subject:
McGuire Nuclear Station Docket Nos. 50-369 and 50-370 Proposed Technical Specification Changes - Revision / Supplement Extension of Allowed Outage Time for VA System
Dear Mr. Denton:
My letter of September 16, 1985 (as supplemented by related information contained in submittals dated September 20 and 23, 1986) submitted proposed license amendments (pursuant to 10CFR50.90) to Facility Operating Licenses NPF-9 and NPF-17 for McGuire Nuclear Station Units 1 and 2, respectively. The proposed amendments would reflect that the Auxiliary Building Filtered Ventilation Exhaust (VA) System consists of two shared systems serving the common Auxiliary Building rather than one system for each of two McGuire units (with an attendant increase in the time allowed to restore an inoperable VA System train to operable status from 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to 7 days). The " Notice of Consideration of Issuance of Amendment to Facility Operating License and Proposed No Significant Hazards Consideration Determination and Opportunity For Hearing" related to the submittal was published in the Federal Register on October 23, 1985.
By Mr. B.J. Youngblood's (NRC/0NRR) letter dated December 20, 1985 the NRC requested additional information regarding this submittal in two areas:
- 1) data justifying that the VA System of lower flow capacity (43,400 cfm, Unit 2) can independently establish negative pressure for those areas normally serviced by the 54,282 cfm (Unit 1) VA System; and 2) data justifying that reduced ventilation flows (of varying degrees) to all cubicles as a result of one VA train providing cooling for LOCA loads in one unit concurrent with shutdown loads without offsite power in the other unit would not have a detrimental effect on equipment operation. Also, as a result of ongoing NRC review of McGuire's VA System several further items have been identified where additional information is requested (reference my September 25, 1986 letter to Dr. J.N. Grace (NkC/ Region II)). The requested information is provided as follows:
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i Mr. Harold R. Danton October 9,'1986 Page 2 f
4 Test resulta justifying that the VA System of lower flow capacity can independently establish negative pressure for those areas normally serviced by the higher flow capacity system was provided in the above referenced September 25, 1986 letter (please note that the first paragraph of Attachment 1 of that letter indicates that the VA System was demonstrated capable of maintaining a slight negative pressure in the building with only "one of two exhaust fans operating" - this should read "one of two exhaust trains operating" where " train" refers to what is currently a single unit's VA System).
In addition to the above, as documented in the September 25, 1986 letter Duke committed to pursue a good faith effort to t
improve system performance on level 695' (ECCS pump rooms) with a goal of meeting 0.25" w.g. relative to atmosphere. Toward this end-Duke has performed additional testing (see Attachment 1) which shows that the Unit 1 and 2 ECCS pump rooms (some of which are also located on the 716' elevation) can be maintained at-a negative pressure with respect to atmosphere of greater than or equal.to 0.25" w.g., with e
the exception of the NI Pump 1A room (0.22" w.g.) [ Note that the NRC resident inspector witnessed portions of this additional testing].
With regard to NI pump 1A room, Duke believes that with minor flow adjustments the greater than or equal to 0.25" w.g. goal can be met, and accordingly intends to perform further testing in the near future to demonstrate this. However, it should be noted that the relevant Licensing basis of the plant is that the VA System is designed to provide "a slightly negative building pressure with respect to atmosphere to minimize outleakage" [ reference SSER March 1978 Section 9.4.2, and FSAR section 9.4.2] with no minimum differential _ pressure limit specified. Consequently, while Duke will strive to meet the 0.25" w.g. performance goal-(appropriate testing will be performed at 18 month intervals and any significant degradation will be j
evaluated), this limit is not considered to be an acceptance criteria for system operability and any NRC attempt to impose such a limit would be a backfit subject i
to the provisions of 10CFR50.109.
b provides the requested justification regarding post-accident heat removal, as well as information concerning the effects of humidity on the VA System. Again, since the M Juire VA System design has received previous NRC approval [ reference SSER March 1978 Section 9.4.2] Duke's position is that any NRC desired design changes (e.g. preheaters) to improve effective sustained operation of the VA System during humid conditions should be pursued through the backfit provisions of 10CFR50.109.
! is a revision to page 3/4 7-16 of the VA System Technical Specification changes proposed by the September 16, 1985 submittal. The original i
proposal, while correctly changing the LCO portion of the VA' System Technical i
Specification to reflect that the VA System will consist of two shared systems rather than one independent system for each McGuire unit, inadvertently neglected to make similar changes to the surveillance requirements portion of the specification. The revision corrects this oversight by rewording surveillance requirement 4.7.7 to read "Each Auxiliary Building Filtered Ventilation Exhaust System..." instead of "The Auxiliary...".
This is an editorial change only and j
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Mr Harold R. Denton October 9, 1986 Page 3 the previous amendmente, justification and safety analyses, and no significant hazards considerations remain valid. No further changes to the Technical Specification Bases pages are required for this revision. Also please note that the two dates in the last sentence of my September 23, 1985 letter were transposed, and should actually state that certain information in the September 20,.1985 submittal may be useful in the review of the September 16, 1985 request.
The McGuire FSAR will be appropriately revised to reflect this shared system concept in the applicable annual FSAR. update following approval. These aspects have previously been discussed in telecons between Mr. P.B. Nardoci (DPC) and Mr.
D.S. Hood of your' staff.
Since this letter revises and supplements proposed license amendments provided in my September 16, 1985 submittal which is currently under review, no additional amendment fees are necessary. Duke believes that the information contained in this letter (along with numerous telecons between various members of our respec-tive staffs in September and October,1986) satisfactorily resolves all outstand-ing issues with respect to the proposed license amendment, and requests that it be issued on a timely basis. - Should there be any questions concerning this matter or i
if additional information is required, please advise.
Very truly yours,
- b. #
Hal B. Tucker PBN/33/j gm Attachments xc: w/ attachments Dr. J. Nelson Grace Mr. W.T. Orders Regional Administrator 1000 Resident Inspector U.S. Nuclear Regulatory Commission McGuire Nuclear Station 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323 Mr. Dayne Brown, Chief Radiation Protection Branch Division of Facility Services Department of Human Resources P.O. Box 12200 Raleigh, N.C.
27605 Mr. Darl Hood, Project Manager Office of Nuclear Reactor Regulation U.S. Nuclear kegulatory Commission Washington, D.C.
20555
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