ML18153B588

Proposed Tech Specs Clarifying Operability Requirements of Individual Rod Position Indicating Sys During Reactor Startup & Power Operations

ML18153B588
Person / Time
Site:	Surry
Issue date:	01/25/1989
From:	VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:
Shared Package
ML18153B587	List: ML18153B586 ML18153B588
References
NUDOCS 8901270327
Download: ML18153B588 (3)

Text

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ATTACHMENT I Proposed Technical Specification Changes

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• 3.12-10

5. If power has been reduced in accordance with Specification 3 .12. C. 5. b, power may be increased above 75'% power provided that:

a) an analysis has been performed to determine the hot channel factors and the resulting allowable power level based on the limits of Specification 3.12.B.1, and b) an evaluation of the effects of operating at the increased power level on the accident analyses of Table 3.12-1 has been completed.

D. Core Quadrant Power Balance:

1. If the reactor is operating above 75% of rated power with one excore nuclear channel out of service, the core quadrant power balance shall be determined:

a. Once per day, and

b. After a change in power 1eve 1 greater than 10% or more than 30 inches of control rod motion.

2. The core quadrant power balance shall be determined by one of the following methods:

a. Movable detectors (at least two per quadrant)

b. Core exit thermocouples (at least four per quadrant)

E. Rod Position Indicator Channels

1. Rod Position Indication shall be provided as follows:

a. Above 50% power, the rod position indication system shall be operable and capable of determining the control rod positions to within +/-12 steps of their respective group step demand counter indications.

b. From movement of control banks to achieve criticality up to 50% power, the rod position indication system shall be operable and capable of determining the control rod positions to within +/-24 steps of their respective group step demand counter indications for a maximum of one hour out of twenty-four, and to within +/-12 steps otherwise. During the one-hour "Thermal Soak" period, the step demand counters shall be operable and capable of determining the group demand positions to within +/-2 steps.

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• TS 3.12-11

c. In hot, intermediate and cold shutdown conditions, the step demand counters shall be operable and capable of determining the group demand positions to within +/-2 steps. The rod position indicators sha 11 be available to verify rod movement upon demand.

2. If a rod position indicator channel is out of service, then:

a. For operation above 50% of rated power, the position of the RCC shall be checked indirectly using the movable incore detectors at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and immediately after any motion of the non-indicating rod exceeding 24 steps, or

b. Reduce Power to less than 50% of rated power within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. During operations below 50% of rated power, no special monitoring is required.

3. If more than one rod position (RPI) indicator channel per group or two RPI channels per bank are inoperable during control bank motion to achieve criticality or power operations, then the requirements of Speci fi cation 3. 0 .1 will be followed.

The reactivity control concept assumed for operation is that reactivity changes a*ccompanyi ng changes in reactor power are compensated by control rod assembly motion. Reactivity changes associated with xenon, samarium,

.fuel depletion, and large changes in reactor coolant temperature (operating temperature to cold shutdown) are compensated for by changes in the soluble boron concentration. During power operation, the shutdown groups are fully withdrawn and control of power is by the control groups.

A reactor trip occurring during power operation wil 1 p1ace the reactor into the hot shutdown condition. The control rod assembly insertion limits provide for achieving hot shutdown by reactor trip at any time, assuming the highest worth control rod assembly remains fully withdrawn, with sufficient margins to meet the assumptions used in the accident analysis. In addition, they provide a limit