ML20037B533

Requests Analyses & Other Relevant Info Needed to Determine Possible Damage in Event of Cask Drop Caused by Sys Failure & Whether Design or Procedural Mods Would Be Appropriate to Reduce Probability of Occurrence

ML20037B533
Person / Time
Site:	Dresden
Issue date:	02/21/1974
From:	Skovholt D US ATOMIC ENERGY COMMISSION (AEC)
To:	Abel J COMMONWEALTH EDISON CO.
References
NUDOCS 8010140671
Download: ML20037B533 (2)

Text

....,4 Distribution s#ocket File AEC PDR FEB 211974 RP Reading Branch Reading ich t 5e. 50-10

-JRBuchanan, ORNL DJSkovholt, L:0R TJCarter, L:0R ACRS (16)

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Co~a:onwealth Pdison Co=pany OGC ATL;;

Mr. J. S. Abel DLLZiemann, L:0RB #2 Kuclear Licensing M inistrator -

RDSilver, L:0RB #2-Lolling Water Reactors RMDiggs, L:0RB #2 Post Office Box 767 SVarga,'L:RP p.

Chicago, Illinois 60690

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M:e Regulatory staff's review of reactor power plant safety includes consideration of postulated spent fuel shipping cask drop accidents.

Tnese events must be adequately docu::ented and analyced by licensecs and ap >licants and evaluated by the staff. Possible damage that could occur to plant structures, systems, and components ir:portcut to cafety in the event of a cack drop caused by a failure in the crane syste= or handling devices n:ust be evaluated. Our review of the FSt.R (b'azards Sir mng Ee. port) for Drcsden Unit 1 indicates that the probability of damage from these. postulated events has not been explicitly cdd2cssed and evaluated.

We request that you provide us with analyces and other relevant infor -

nation needed to determine the poscible dacar.e in the event of a ecsk drop caused by a system failure and whether design or prccedural todi--

fications vould be appropriate to reduce the probability of occurrence.

Areas of particular concern which should be includcd in your evaluation are the following:

1.

Integrity of the spent fuel storage pool - If the cask should drop while being handled over the storage pool, would t'te pool floor be damaged to the extent that ruheup capability could not be cssured?

2.

Upont fual integrity - Can the ccok be pocitioned ucar spent fuel so t at a cask can drop on the spent fuel or be deficetec onto the cpent fuel if it should hit a pool cd;;c?

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Co:2onvcalth Edison Co=pany p{g i i gg 9

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Lescriptien of the handling-equipocat for thc cpeat fuul cas,.

Fruvide a description of the crana facilities currently instclied in the plent, indicating design conditions to uhich they were dec1gned, the tests that have been perforned on the crenes in accordance uith accepted code procedures and describe the factor of safety that you believe to cr.ist in the current crane oyaten.

Particular attention should be given to control brcking versus energency holding brakes that are currently installed. Evaluate the re h m stall torque of the crane notor and the capability of the brakes to preclude this torque being transmittcJ to the load -

being lifted. Describe any other protective features that are instc31cd that would prevent a tno blocking situation from occurring should the load be raised too high. Also provido a description of cll lifting devices such as clings, hecks, repca r cnd the attachcants to the spent fual cask.

If the results of your analysis indicate that changes in the design of your fuel shipping cash crane syste:as or handHng devices are necessary to protect plant structures, systems, or conponents important to scfety 7

or to prevent spent fuel damage, please provide infor=ation on your plans to revise the design of your facility or equipment as required.

We vill need esticates of the schedule for design, fabricatien, and installation of any nodifications found to be neccuscry. The report of your cnalysis and any prcposed nodifications should be cubmitted as an amendment to' the Safety Analysis Report by May 15, 1974. Cec signed and thirty-nine copics of the amendrant should be provided.

Sinc'erely,

cmp.en se.d cr

n. J. skovboh Dotald J. Skovholt Assistant Director for Operating Fe. actors Directorate cf Licccsing cc: Jchn i!. Rova. L:quirc Ichnn, Linccin L Lecle Counselors at Ls.

One Firct Sctional l'lara Cnicago, Illinois 60670 Anthony Z. Eoisnan, Esquire Berlin. Eoisman and Kessler 1712 H Strcct, U. U.

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