ML20081G933
| ML20081G933 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 03/16/1995 |
| From: | Stetz J CENTERIOR ENERGY |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 2267, IEB-88-011, IEB-88-11, NUDOCS 9503240013 | |
| Download: ML20081G933 (2) | |
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- GNTERNHt
- W ENERGY 300 Madison Avenue John P. Stetz Toledo, OH 43652-0001 Vee President Nuclear 419-249-2300 Davis-Besse Docket Number 50-346 License Number NPF-3 Serial Number 2267
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March 16, 1995 1
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United States Nuclear Regulatory Commission Document Control Desk Washington, D. C.
20555
Subject:
Completion of Actions Relating to Bulletin Number 88-11, " Pres-l surizer Surge Line Thermal Stratification" l
Gentlemen l
The purpose of this letter is to inform the NRC of Toledo Edison's comple-tion of its actions relating to Bulletin Number 88-11, " Pressurizer Surge l
Line Thermal Stratification," at the Davis-Besse Nuclear Power Station l
(DBNPS) Unit Number 1.
This letter was requested by the NRC' Staff in its letter (Toledo Edison Log Number 4189) dated April 15, 1994 (reference:
TAC Number 72128).
Toledo Edison has completed the following final actions which vere prev-iously discussed in its letter (Serial Number 2190) to the NRC dated December 3, 1993:
- 1. Modifications were completed during the Ninth Refueling Outage (9RFO) pursuant to ensuring that the pressurizer surge line whip restraints and variable spring support PSU-H1 do not interfere with surge line thermal displacement. Also, the anchor bolts on the support structure for PSU-R1 (the restraint to which PSU-H1 was formerly attached) were restored to a safety factor of four. The l
9RF0 was completed on November 15, 1994.
- 2. The pressurizer surge line thermal insulation was modified during j
the 9RF0 pursuant to ensuring that the the top-to-bottom tempera-l ture differences in the surge line are reduced.
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Operating Companies:
Cleveland Electnc muminating O
Toledo Edison 9503240013 950316 i
PDR ADOCK 05000346 l
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8 Dock 2t Nurber 50-346 Liccn o Nu b;r NPF-3 S:ri'cl Nu:ber 2267 i
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- 3. The pressurizer. surge line thermal conditions were monitored during heatup from the 9RF0 pursuant to confirming the conservatism of the plant-specific analysis for future surge line conditions. The data i
obtained from this monitoring has been evaluated and the structural integrity of the surge line has been confirmed for the 40-year design life of the DBNPS, while considering the effects of thermal j
stratification.
- 4. The number of heatups and cooldowns were monitored to ensure that the 50 heatup/cooldown cycles related to the justification for continued operation in place until the completion heatup from 9RF0 were not exceeded. With the completion of the above described activities, this action is complete.
Should you have any questions or require additional information, please contact Mr. Villiam T. O'Connor, Manager - Regulatory Affairs, at (419) 249-2366.
Very'truly yours, DRW/laj cc:
L. L. Gundrum, DB-1 NRC/NRR Project Manager J. B. Martin, Regional Administrator, NRC Region III i
S. Stasek, DB-1 NRC Senior Resident Inspector Utility Radiological Safety Board i
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