ML20078K300

Proposed Tech Specs Re Mod to Basis Section for TS 15.3.3, Eccs,Acs Air Recirculation Fan Coolers & CS for Plant Units 1 & 2

ML20078K300
Person / Time
Site:	Point Beach
Issue date:	02/01/1995
From:	WISCONSIN ELECTRIC POWER CO.
To:
Shared Package
ML20078K296	List: ML20078K300 NPL-95-0046, Submits Mod to Basis Section for TS 15.3.3, Eccs,Acs,Air Recirculation Fan Coolers & CS, for Plant Units 1 & 2
References
NUDOCS 9502090162
Download: ML20078K300 (1)

Text

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. s Assuming 1.he reactor has been operating at full rated power for at least 100 days, the magnitude of the decay heat decreases as follows after initiating hot shutdown.*

Time After Shutdown Decay Heat % of Rated Power 1 min. 3.6 30 min. 1.55 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> 1.25 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> 0.7 l 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> 0.4 i

• Based on ANS 5.1-1979, " Decay Heat Power in Light-Water Reactors" l I

Thus, the requirement for core cooling in case of a postulated loss-of-coolant  ;

accident while in the hot shutdown condition is significantly reduced below the requirements for a postulated loss-of-coolant accident during power operation.

Putting the reactor in the hot shutdown condition significantly reduces the poten-tial consequences of a loss-of-coolant accident, and also allows more free access to some of the engineered safety system components in order to effect repairs.

When the failures involve the residual heat removal system, in order to insure redundant means of decay heat removal, the reactor system may remain in a condition with reactor coolant temperatures greater than 350af so that the reactor coolant loops and associated steam generators may be utilized for redundant decay heat removal . However, when the remaining RHR loop must be relied upon for redundant decay heat removal capability, reactor coolant temperatures shall be maintained between 350'F and 140 F.

With respect to the core cooling function, there is some functional redundancy for certain ranges of break sizes.*

The operability of the Refueling Water Storage Tank (RWST) as part of the ECCS ensures that a sufficient supply of borated water is available for injection by the ECCS in the event of either a LOCA or a steamline break. The limits on RWST 9502090162 950201 PDR ADOCK 05000266 P pop 15.3.3-8 December 21, 1994 Unit 1 - Amendment No. 159 Unit 2 - Amendment No. 163