ML18113A748

Responds to NRC 781128 Ltr Re Containment Purging During Normal Plant Operation.Units Operate w/sub-atmospheric Containment Per Tech Specs.Containment Purging Operations Not Allowed & Procedures Provided to Prevent Override

ML18113A748
Person / Time
Site:	Surry
Issue date:	01/03/1979
From:	Stallings C VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	Schwencer A Office of Nuclear Reactor Regulation
References
690-112878, NUDOCS 7901080139
Download: ML18113A748 (1)

Text

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. . .* REGULATORY DOCI\ET FHF r,(JDY *.

• VIRGINIA ELECTRIC AND POWER COMPANY .*- '.". ij .* '

RICHMOND,VIBGINIA 23261 January 3,' 1979:

Mr. A. Schwencer, Chief Serial No. 690/112878*

Operating Reactors Branch 1 PO/DAC:scj Division of Operating Reactors Docket No.: 50-280 U.S. Nuclear Regulatory Commission. 50-281 Washington, D. C. 20555 License No.: DPR-32

. DPR-37

Subject:

Containment Purging During Normal Plant Operation Surry Power Station Unit Nos. 1 and 2

.. This is. in response to your letter of November 28,

• 1978 regaz:ding.

containment purging during 'operation.

Since both Surry units operate with sub-atmospheric containments as.

specified *in' the' Technical Specifications, containment purging* operations are not all.owed during power operat_ion, hot standby' or hot shutdown conditions. The Technical Specifications require that containment integrity be established prior to increasing reactor coolant temperature above 200F and that containment *air partial pressure be within specification before exceeding 350F. Operation of the purge inlet and-outlet valves above 350F would result in a violation of the Technical Specification concerning containment internal pressure.

Current Technical Specifications require that containment vacuum be maintained for all plant conditions for which engineered safeguards systems are required operational. Physical limitations prohibit containment purging unless containment vacu~m is broken. Furthermore, purge valves receive an automatic signal to close on a high radiation signal and there is no install-ed override capability for this function. For these reasons, we do not feel that an amendment to Technical Specifications is required. in regard to *-:;~

purging operations.

In addition, a review of safety injection override circuitry at Surry was conducted. On the basis of this study, it is our position that sufficient physical features, administrative controls, and procedures are provided at Surry to prevent an unsafe override of equipment important to safety.

Very truly yours,

.*  ;*

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. C. M. Stallings '

Vice President-Power Supply cc:. Mr. James P. O'Reilly and Production Operations p