ML20081G090

Final Deficiency Rept 102 Re Damaged Control Rod Blades on RHR Pumps.Initially Reported on 830927.Blade Guides Which Interfered W/Control Rod Insertion Are Temporary & Will Be Replaced W/Fuel Bundles at Fuel Load

ML20081G090
Person / Time
Site:	Fermi
Issue date:	10/27/1983
From:	Wells D DETROIT EDISON CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
102, 10CFR-055.55E, 10CFR-55.55E, EF2-65289, NUDOCS 8311040110
Download: ML20081G090 (2)

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• OU (313) 237-8000 EF2-65289 Mr.-James G. Keppler,' Regional Administrator Region III U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, Illinois 60137

Subject:

Report of 10CFR50.55(e) Item on Damaged Control Rod Blades

(#102)-

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Dear Mr. Keppler:

' This is Detroit Edison's final report concerning damaged control rod

. blades at the Fermi 2 site. The-item was originally reported on

' September 27, 1983, to Mr. J. Konklin of NRC Region III by Detroit Edison's Mr. W. R. Wingfield, Quality Engineer - Construction Quality Assurance.

On September. 22, 1983, a problem was discovered following Preopera-

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tional Test E1100.001 ("Three RHR Pump Run"). While inserting the control rods, some operated sluggishly and others would not fully insert.. Attempts to insert additional rods were stopped pending

- f urther_ . inve s tigation. .The initial investigation revealed there was actual damage sustained to two (2) of the control rod blades and two (2) orifice fuel supports. A detailed inspection of core internals identified three (3) peripheral control rods that could not be fully inserted due to a stoppage by blade guides which were out of position.

A detailed plan will be. developed and implemented prior to further three,(3)~or four (4) RHR pump run attempts.

Further investigation revealed a misalignment of several control rod blade guides. A differential pressure across the core plate during the previous "Three RHR Pump Run" had caused a lift of the blade guides. A detailed plan to inspect control rod blades, orifice fuel support castings and blade guides has been developed and implemented.

An evaluation of safety implications has determined that there is no compromise of safety or reliability.- The ability to insert control rods is a safety concern only when fuel is installed in the core.

Enrico Fermi 2 has not loaded fuel. Even if the occurrence had gone undetected, the ability'to insert control rods with fuel in the core would'not-have been jeopardized. The blade guides which interferred with the control' rod ineertion are temporary, and will be replaced by fuel bundles .at fuel load; removal of the temporary guide would have eliminated any interference, and all control rods could have been inserted when~ fuel was in the core.

8311040110 831027 "

PDR ADOCK 05000341 #

M OCT 311983 1 9

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-Mr. Jane's G. Keppler, Regional Administrator J 0ctober- 27,-.1983:

EF2-65289

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,Pagec2-The 'following - precautions were taken' to prevent : blade guide lif t

. during;.a' subsequent RHR Pump' Run on October 7,1983:

Removal, of the temporary-0* manway cover;

_ fa.

JE; (Removallof; all blade -guides, except for four (4)' single blade -

guides tied around-each incore probe;-

c. Removal of all peripheral fuel support pieces;-

p d. . Assuring that the water level is over the blade guides prior to LPCl injection;-

e. -Verify proper blade guide position subsequent to each three (3) or four (4) pump'RRR injections; and

f. . + Verify _ all blade zguides for proper blade guide positions af ter

- reinstallations in: support of CEE) operation.

Similar precautions will be taken during further' RHR three (3) and four'(4) pumpLvessel injections.

-If;you have questions concerning this matter, please contact Mr. G. M. Trahey, Assistant Director -' Project. Quality Assurance.

> Very truly yours, r

cc: Mr; Richard DeYoung, Director

' Office of Inspection and Enforcement

.U.S. Nuclear: Regulatory Commission

-Washington, D.C.. 20555 Mr. Paul Byron,' Senior: Resident Inspector U.S.-Nuclear Regulatory. Commission 6450 North Dixie liighway, Newport, Michigan 48166 x

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