ML20133N881

Responds to Concern Re Adequacy of Preoperational Test to Measure Flow Velocity Distribution of Auxiliary Bldg Filtered Ventilation Sys.Engineering Evaluation Concluded That Ventilation Sys Operable

ML20133N881
Person / Time
Site:	McGuire, Mcguire
Issue date:	10/28/1985
From:	Tucker H DUKE POWER CO.
To:	Adensam E, Harold Denton Office of Nuclear Reactor Regulation
Shared Package
ML20133N885	List: ML20133N881 ML20133N886 ML20133N892 ML20133N894 ML20133N897
References
NUDOCS 8510300209
Download: ML20133N881 (2)

Text

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!sn LEAR PisoptTTtot (704) a73-4 mu October 28, 1985 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Attention: Ms. E. G. Adensam, Chief Licensing Branch No. 4

Subject:

McGuire Nuclear Station Docket Nos. 50-369, -370

Dear Mr. Denton:

During a recent NRC inspection at McGuire, a concern was raised regarding the Auxiliary Building Filtered Ventilation (VA) system. The concern is the adequacy of the pre-operational test to measure flow velocity distribution. This test is required by ANS 510-1975, RG 1.52 and the McGuire FSAR.

Duke committed to perform the test provided acceptance critaria suitable to the McGuire design could be utilized and a plan of action identified in the event the acceptance criteria were not met. On October 23, 1985, NRC/RII issued a Confirmation of ActioD letter (Attachment 1) on this concern.

As committed, Duke conducted air flow distribution tests for the VA, system of each McGuire unit. Attachment 2 to this letter provides the test procedures for Unit 1 (TT/1/A/9100/101A, TT/1/A/9100/101B). Similar test procedures have been prepared for Unit 2. The Acceptance Criteria for Supplemental Filter Testing (MCC-1211.00-00-0096) is provided in Attachment 3. Based on a telephonc conference call on October 24, 1985, NRC confirmed that use of the acceptable criteria from ANSI /ASME N510-1980 was acceptable. NRC also stated that it does not agree with any other acceptance criteria.

The results of the testing conducted are summarized in Attachment 4. For Unit 1, the flow velocity distribution at the HEPA exit exceeds the acceptance criteria and the point to point flow velocity distribution at carbon inlet also exceeds the acceptance criteria. For Unit 2, the flow velocity distribu-tion at the HEPA exit exceeds the acceptance criteria. Duke engineers have reviewed these results and prepared an engineering evaluation which is included in Attachment 4.

Based on these results and the analysis conducted, it is considered that both VA systems at McGuire are operable. Duke also consideres that the existing carbon bed surveillance program is adequate. To provide additional assurance of the adequacey of the existing surveillance program, Duke will have carbon samples from the high velocity location, a rendom location, and from new 8510300209 851028 PDR P

ADOCK 05000369 i j PDR l 1 .

I Mr. Harold R. Denton, Director October 28, 1985 Page 2 charcoal analyzed by a laboratory. Upon receipt of the results, Duke will evaluate what additional actions may be taken. The results are anticipated within two weeks.

If there are any questions regarding this, please advise through normal licensing channels.

Very truly yours, S , SN Hal B. Tucker RLG/hrp Attachments cc: Dr. J. Nelson Grace, Regional Administrator U. S. Nuclear Regulatory Commission Region II 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323 Mr. W. T. Orders NRC Resident Inspector McGuire Nuclear Station Mr. Darl Hood, Project Manager Division of Licensing Office of Nuclear Regulatory Commission Washington, D. C. 20555

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