ML18153C315

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Proposed Tech Specs Re Outside Recirculation Spray & Containment Spray Surveillance Frequency
ML18153C315
Person / Time
Site: Surry  Dominion icon.png
Issue date: 08/01/1990
From:
VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:
Shared Package
ML18153C314 List:
References
NUDOCS 9008060142
Download: ML18153C315 (5)


Text

ATTACHMENT 1 SURRY POWER STATION PROPOSED TECHNICAL SPECIFICATION CHANGE ORS AND CS SURVEILLANCE FREQUENCY

e TS 4.5-2

2. By verifying that each motor-operated valve in the recirculation spray flow paths performs satisfactorily when tested in accordance with Specification 4.0.3.
3. At least once per 5 years, coincident with the closest refueling outage, by performing on air or smoke flow test and verifying each spray nozzle is unobstructed.

C. Each weight-loaded check valve in the containment spray and outside containment recirculation spray subsystems shall be demonstrated operable at least once each refueling period, by cycling the valve one complete cycle of full travel and verifying that each valve opens when the discharge line of the pump is pressurized with air and seats when a vacuum is applied.

D. A visual inspection of the containment sump and the inside containment recirculation spray pump wells and the engineered safeguards suction inlets shall be performed at least once each refueling period and/or after major maintenance activities in the containment. The inspection should verify that the containment sump and pump wells are free of debris that could degrade system operation and that the sump components (i.e., trash racks, screens) are properly installed and show no sign of structural distress or excessive corrosion.

Basis The flow testing of each containment spray pump is performed by opening the normally closed valve in the containment spray pump recirculation line returning water to the refueling water storage tank. The containment spray pump is operated and a quantity of water recirculated to the refueling water storage tank. The discharge to the tank is divided into two fractions; one for the major portion of the recirculation flow and the other to pass a small quantity of water through test nozzles which are identical with those used in the containment spray headers. The purpose of the recirculation through the test nozzles is to assure that there are no particulate material in the refueling water storage tank small enough to pass through pump suction strainers and large enough to clog spray nozzles.

ATTACHMENT 2 SURRY POWER STATION SIGNIFICANT HAZARDS CONSIDERATION DETERMINATION

DISCUSSION OF PROPOSED CHANGE The surveillance requirement in Section 4.5 is being changed to require that the weight-loaded check valves in the Outside Recirculation and Containment Spray Systems be tested every Refueling Period rather than every eighteen (18) months.

This change is being requested so that the surveillance test will be performed during cold shutdown as intended, rather than requiring containment entry at power or a unit shutdown just to complete the test. Performance of this test requires the erection of scaffolding inside containment to reach the valves. This level of work is normally not performed in a sub-atmospheric containment at power for personnel safety. In addition, the change from 18 months to each refueling period does not significantly increase the probability of a valve failure. The valves in question are not operated during normal operations. Futhermore, the normal operating cycle is 18 months and (

the test would typically be performed within the 18 month plus 25% interval. Only if an extended shutdown during the operating cycle for maintenance or resolution of a technical issue was necessary, would the 18 month plus 25% interval be exceeded.

Exceeding the 18 month plus 25% interval on an infrequent basis would have no significant effect on the valve operability.

SIGNIFICANT HAZARDS CONSIDERATION Virginia Electric and Power Company has reviewed the proposed changes against the criteria of 10 CFR 50.92 and has concluded that the changes as proposed do not pose a significant hazards consideration. Specifically, the proposed Technical Specifications change will only change the frequency of the surveillance test for the Outside Recirculation Spray and the Containment Spray weight-loaded check valves from once every eighteen (18) months to once per Refueling Period. A refueling period is nominally 18 months unless an unexpected equipment problem or technical issue requires an extended shutdown. Thus, operation of the Surry Power Station in accordance with the proposed changes will not:

1. Involve a significant increase in the probability or consequences of an accident previously evaluated. Operation of Surry Power Plant will not be changed Performing the surveillance of the Outside Recirculation Spray and Containment Spray weight-loaded check valves on a refueling period frequency rather than an eighteen (18) month basis will not significantly

........ ) .

e increase the potential for a stuck check valve and or the loss of a train of either system. The normal operating cycle fuel load is designed for eighteen months and the surveillance test will normally be performed every 18 months plus or minus 25%. Only when an extended outage is required for maintenance or resolution of a technical issue would the surveillance period extend beyond the plus 25% range. Operation of plant equipment is not being modified.

2. Create the possibility of a new or different kind of accident from any accident previously evaluated. Changing the surveillance frequency of the Outside Recirculation Spray and Containment Spray weight-loaded check valves has no impact on plant design or operation and in no way impacts the accidents previously analyzed. Therefore, no new or different kind of accident is created.
3. Involve a significant reduction in the margin of safety. No physical plant modifications, changes in plant operations, or changes in accident analysis assumptions are being made. Therefore, the accident analysis assumptions remain bounding and safety margins remain unchanged.