ML20149D797
| ML20149D797 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 01/06/1988 |
| From: | Counsil W, John Marshall TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| CP-87-129, TXX-88031, NUDOCS 8801130124 | |
| Download: ML20149D797 (2) | |
Text
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- TXX-88031 Fi e # 10110
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906.5 Ret. f 10CFR50.55(e) 7UELECTRIC I,I,'",U 5",$,,,
January 6, 1988 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C.
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SUBJECT:
COMANCllE PEAK STEAM ELECTRIC STATION (CPSES) 00CAET N05. 50-445 AMD 50-446 CONTAINMENT SPRAY SYSTEM PH SDAR: CP-87-129 (INTERIM REPORT)
Gentlemen:
On December 7, 198:, we verbally notified your Mr. H. S. Phillips of a deficiency involving the containment spray pH, Due to the nature and extent of the analysis necessary to evaluate the containment spray pH effects on safety-related equipment, this item is being conservatively identified as reportable under 10CFR50.55(e).
The iequired information follows.
DESCRIPTION The containment spray system (CSS) pH calculatica was performed for the injection phase when tha containment spray borated refueling water storage tank (RWST) pumps are taking suction from the While in this phase, the RWST water is buffered with sodium hydroxide (Na0H) via the containment spray pump eductor to ebtain a spray pH of approximately 10.
However, during the operation of the CSS following an accident, the pump suction is shifted from the RWST to the containment sump prior to depletion of the chemical addition tank (CAT) contents.
For a period of approximately 30 minutes Na0H from the i
CAT will be added to sump water which has a higher pH than RWST water.
The adjusted spray pH will then reach approximately 13 which will exceed the maximum of 10.5 specified in FSAR Section 6.5.2, and which was used for equipment qsalification specifications.
i In addition, if either CAT supply isolction valve LV4754 or LV4753 fails to
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open under receipt of an open signal ("P"), the containment spray train i
associated with this failed vah? will inject untreated RWST water directly into the containment during the injection phase.
The spray pH associated with untreated RWST water is approximately 5, which is below the 8.5 minimum pli specified in the FSAR.
If either normally open valve LV4752 or tV1753 were to be inadvertently closed, the same results would occur.
After depletion of the RWST contents, a possible high pH condition could exist, but for a longer period of time than that discussed in the previous paragraph, Note that in this case, i.e., assuming a valve failure, the out-of-range pH would exist in one spray train only.
The pH of the spray from the other train would be in the expected range.
8801130124 880106 PDR ADOCK 05000445 dl.7 g
PDR J th ohve street LB81 Dallas Texas 7201
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p TXX-88031 January 6, 1988 Page 2 of 2 SAFETY IMPLICATIONS The potential violation of the environmental qualification envelope of safety related equipment inside containment could impair the ability to mitigate the c;nsequences of a LOCA, or to achieve and maintain shutdown.
Due to the nature and extent of this condition we ha.e conservatively assumed that this condition could adversely affect the safety of operations.
CORRECTIVE AC110N We are evaluating the required corrective actions for this deficiency. Our next report on this issue will be submitted no later than February 26, 1988.
Very truly yours, kl,6, C a n L W. G. Counsil
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By:
J. S. Marshall Supervisor, Generic Licensing BSD/mlh c - Mr. R. D. Martin, Region IV Residerit inspectors, CPSES (3) d 6
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