ML20010H783

Proposed Tech Specs Changes Eliminating Environ Monitoring of Embayment to Determine Proper Rate of Discharge Temp

ML20010H783
Person / Time
Site:	Arkansas Nuclear
Issue date:	09/24/1981
From:	ARKANSAS POWER & LIGHT CO.
To:
Shared Package
ML20010H779	List: ML20010H778 ML20010H783
References
NUDOCS 8109290290
Download: ML20010H783 (2)

Text

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2-3 95 F as established by the applicable water quality criteria.

The use of the condenser discharge RTD's provides the circu-lating water discharge temperature prior to mixing with the Dardanelle Refervoir water.

No credit was taken in the analyses and models of the circu-lating water system for heat exchange within the discharge embayment even though it is expected that the water temperature will be reduced in the embayment. Thus, the average tempera-ture should be 6 105 F even when the temperature at the con-denser discharge is greater.

2.1.3 Maximum BTU /hr Not applicable.

2.1.4 Rate of Change of Discharge Temperature Objective To avoid thermal stress to the aquatic ecosystem due to sudden changes in water temperature.

l Specification In the event of a planned shutdown during the period November through April, the reactor power level shall be redeced to 0%

at a rate such that the decrease in the condenser circulating water discharge temperature shall be 5 5*F/hr in order to avoid any adverse thermal impact on the aquacic environment in the discharge embayment. As the reduction in power level is made, I

the number of operating circulating water pumps will be reduced so as to limit the rate of decrease of the water temperature in the discharge embayment.

This limitation may be exceeded for brief periods as necessary to protect plant equipment and for certain safeguard operations which cannot be limited or negated by plant operation. These safeguard operations include automatic plant trips and compli-ance with safety-related technical specifications.

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2-4 Monitoring Requirement Condenser discharge water temperature will be monitored every hour during the power reduction utilizing the average of the computer output of the conden~ - discharge RTD readings. The RTD's have a 0-150*F range anc. a accure.cy of 10.5%.

If the plant computer is inoperable, the condenser discharge water temperature shall be monitored at least once per hour during the power reduction utilizing the condenser temperature recoroer which nas a 0-150*F range and a 10.5% accuracy.

Bases There has been no incidence of adverse environmental impact associated with any operating AP&L power plant. Based on data collected at the plant over a six year period, a rate of change of 6 5 F/hr is specified. Also, the actual rate of change of the discharge embayment will be slower than the rate of change of the circulating water system. A reduction in circulating water flow will further decrease the rate of change of tempera-ture in the discharge embayment.

2.1.5 deat Treatment of Circulating Water System Not applicable.

2.1. 6 Deicing Operations Not applicable.

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