ML20096C270

Proposed Changes to Tech Specs,Revising Section 5.3.1.E to Remove Weight Limitation of Spent Fuel Shipping Cask

ML20096C270
Person / Time
Site:	Oyster Creek
Issue date:	08/28/1984
From:	GENERAL PUBLIC UTILITIES CORP.
To:
Shared Package
ML20096C038	List: ML20096C033 ML20096C039 ML20096C270
References
NUDOCS 8409050191
Download: ML20096C270 (1)

Text

o 5.3 Al)XILIARY EQUIPMENT.

5.3.1 Fuel Storage A. Normal; storage.for unirradiated fuel assemblies ,is in critically-safe new fuel storage racks in the reactor building storage vault; otherwise, fuel, shall! be stored in arrays which hive a Keff less than 0.95 under optimum conditions of moderation or in NRC-approved shipping containers.

• B. . The' spent. fuel-shall be stored in the spent fuel storage facility which shall be designed to maintain fuel in a geometry providing a K

oo les{ then ur equal to 0.95.

C. The $aximum U-235 loading in grams of U-235 per axial centimeter of

- fuel shall not exceed 15.6 gms U-235/cm.

D. . Loads greater than the weight of one fuel assembly shall not be moved over stored irradiated fuel in the spent fuel storage facility.

E. The spent fuel shipping cask"shall not be lifted more than six inches

• above the top plate of the cask drop protection system. Vertical limit switches shall be operable to assure the six inch vertical limit is met when the cask is above the top plate of the cask drop protection system. .

F. The temperature of theswater in the spent fuel storage pool, measured at or near the surface, shall not exceed 1250F.

BASIS 1

~

The specification of Koo 0.95-t.nd the m'aximum,U-235, loading of 15.6 gm U-235/cm pcr axial centimeter for fuel in the spent. fuel storage facility assures ~an ample margin. from criticality. Conservative assumptions and allowance for tolerances, void effects, calculational uncertainties, pool temperature effects, etc. have been considered in the. derivation of these limits (1,2).' Note that the 15.6 gm U-235/cm is equivalent.to a 3 w/o enrichment. (7) .

The 15.6"gm U-235/cm is.the limit of U-235 at;any plane through the assembly perpendiculer to the length of the assimbly. It is to assure that possible non-uniform enrichments along the length of fuel rods cannot lead to a critical condition.

~

i The effects of a dropped fuel bundle onto stored fuel in the spent fuel .

l storage facility has been analyzed. This analysis shows that the fuel bundle i drop would riot cause doses resulting from ruptured. fuel pins that exceed 10 CFR 100 limits .(3, 4, 5) and that dropped wasteican,s will not damage the pool ifner.- -

i i -The elevation l' imitation of the spent fuel shipping cask to no more than 6 l- inches above the top plate of the cask drop protection system prevents loss of the pool integrity resulting from postulated drop accidents. An analysis of the effects of a 100 ton cask drop from 6 inches has been done (6) which showed that the pool structure is capable of. sustaining the loads imposed L during such a drop. Limit switches on:the crane restrict the elsvation of the l cask to 6 inches when.it is above the top plate.

l s '\

Amendment No. 22. ,

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