ML20065B924

Informs That Util Commits to Listed Conditions Applicable to Cycle 10 Startup from Current Unplanned Shutdown from Remainder of Cycle 10 Operation

ML20065B924
Person / Time
Site:	Three Mile Island
Issue date:	03/26/1994
From:	Broughton T GENERAL PUBLIC UTILITIES CORP.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
C311-94-2147, NUDOCS 9404040204
Download: ML20065B924 (2)

Text

j GPU Nuclear Corporation ' I J Nuclear argnir*

Middletown, Pennsylvania 17057-0480 (717)944-7621 i Writer's Direct Dial Number:

March 26, 1994 C311-94-2147 U. S. Nuclear Regulatory Commission Att: Document Control Desk Washington, DC 20555 l

Dear Sir:

.i

Subject:

Three Mile Island Nuclear Generating Station, Unit 1 (TMI-1)

Operating License No. DPR-50  ;

Docket No. 50-289 i

Cycle 10 Control Rod Drop Times Pursuant to discussions with NRC on March 25, 1994 GPU Nuclear commits to the '

following conditions applicable to Cycle 10 startup from the current unplanned shutdown and for the remainder of Cycle 10 operation.

1. GPU Nuclear requests that Technical Specification Change Request (TSCR) No. 242 submitted March 22, 1994 be withdrawn. Exigent i circumstances regarding control rod drop time test criteria no -i longer exist, as all control rods are~ currently within existing Technical Specification requirements.

2. GPU Nuclear will perform the following short term corrective actions-to minimize crud buildup within the control rod drive mechanism.

l A. Increase lithium concentration in the Reactor Coolant System j (RCS) to raise pH to reduce the rate of corrosion. )

B. Control rod drive mechanisms will be exercised every two weeks  !

during the remainder of Cycle 10 to reduce.the likelihood of crud buildup in.the gap between the. lead screw and the. thermal' barrier bushing.

C. Control rod drop times will be obtained within three months of Reactor startup.

9404040204 940326 PDR p

ADDCK 05000289 PDR

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f GPU Nuclear Corporation is a subsidiary of General Pubhc Utsties Corporation

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. 1 C311-94-2147 P(ge 2 of 2 i

3. Within two months of the date of this letter GPU Nuclear will submit our evaluation criteria and a contingency plan to be utilized for the control rod drop time test described in 2C above.

4. If TMI-l experiences an unplanned shutdown prior to the control rod drop time test described in 2C above, TMI-l will. verify that all control rods are within the existing Technical Specification acceptance criteria of 1.66 seconds.

5. If during control rod drop time testing conducted in accordance with Items 2C and 4 above, any control rods exceed the 1.66 second drop time criteria, such rods will not be exercised prior to obtaining NRC approval. ,

6. If during control rod drop time testing conducted in accordance with Items 2C and 4 above, any control rods fail the 1.66 second drop time criteria, NRC approval may allow exercising these rods to within drop time criteria. If NRC approval is not obtained to'-

exercise these rods, or these rods cannot be exercised to within the 1.66 second drop time criteria, at least one control rod drive mechanism will be removed and inspected.

7. Within six months of the date of this letter, GPU Nuclear will provide a long term plan to address necessary actions to improve control rod drive mechanism performance and reliability. The intent of this plan is to ensure that control rods will continue to satisfy the current Technical Specification drop time criteria of 1.66 seconds.

As agreed, TMI-1 plans to return to power operation on March 26, 1994.

Sincerely, T. G. Broug ton DJD/plp cc: Region I Administrator TMI-l Senior Project Manager TMI Senior Resident Inspector Director, Project Directorate 1 Director, Division of Reactor Projects, Region I

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