ML20125A576

Concludes That Proposed Amend Does Not Involve Significant Hazard Considerations Not Previously Evaluated & That There Is Reasonable Assurance That Health & Safety of Public Will Not Be Endangered by Proposed Activities

ML20125A576
Person / Time
Site:	Monticello
Issue date:	02/20/1973
From:	James Shea US ATOMIC ENERGY COMMISSION (AEC)
To:	Ziemann D US ATOMIC ENERGY COMMISSION (AEC)
References
NUDOCS 9212080400
Download: ML20125A576 (1)

Text

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• UNITED ST ATES ATOMIC ENERGY COMMISSION W ASHtNGT ON. D C 2 0 *> 4 *-

%n e/ February 20, 1973 Files (Docket No. 50-263)

Ziemann, Chief, ORB #2, L THRU:b.Dk.

MONTICELLO - .lANGE TO ALLOW 50 GRAMS OF U-235 FOR FISSION CHAMBERS INSTEAD OF ONE GRAM (NORTHLid STATES POWER COMPANY)

By letter dated February 5, 1973, Northern States Power Company (NSP) proposed an amendment to Provisional Operating License No. DPR-22 for the Monticello Nuclear Generating Plant. The proposed amendment would permit the receipt, possession, and use of up to 50 grams of U-235 contained in fission chambers for use during refueling outages. The proposed amendment will not affect normal reactor operations since the large fission chambers (dunkers) can be inserted in emptj fuel bundle positions only when the reactor vessel head and other upper reactor vessel internals are removed from the reactor vessel for fuel inspection or refueling purposes.

Up to six fiss.on chambers, each containing 2 to 6 grams of U-235, may be inserted into the core or core periphery whenever improved neutron detection sensitivity is required during the refueling operations to demonstrate the required shutdown margins. All dunkers must be removed before reinstallation of the upper reactor vessel internals and reactor vessel head can be accomplished because of physical interference. The change is necessary because each of the large fission chambers contains more U-235 than all of the miniature fission chambers used for normal reactor control combined.

We have concluded that the proposed amendment does not involve significant hazard considerations not previously evaluated and that there is reasonable assurance that the health and safety of the public will not be endangered by the proposed activities. ,

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gpu.a -- <.o em James Shea Jperati Reactors Branch #2 Directorate of Licensing cc: Northern States Power Company PDR

,..,,,m Local PDR D. J. Skovholt, L 0R R0 (3)

D. L. Ziemann, L:0R #2 J. J. Shea, L:0R #2 R. M. Diggs, L'OR #2 R. Tedesco, L:CS (2)

M. Jinks (2) 9212080400 730220 f I: J PDR ADOCK 05000263 P PDR

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