ML20053D747
| ML20053D747 | |
| Person / Time | |
|---|---|
| Site: | Zion File:ZionSolutions icon.png |
| Issue date: | 06/02/1982 |
| From: | Lentine F COMMONWEALTH EDISON CO. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| 4259N, NUDOCS 8206070281 | |
| Download: ML20053D747 (2) | |
Text
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/
's Commonwealth Edison
[
) one First Nation 11 PLm, Chicago, lihnois (O
Addrass R; ply to: Post Offica Box 7if7 Chicago, tilinois 60690 Jun e 2, 1982 Mr. Harold R. Denton, Director Of fice o f Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington,_DC 20555
Subject:
Zion Station Unit 1 Proposed Change to Facility Operating License No. DPR-39 NRC Docket No. 50-295 References (a):
May 21, 1982, letter from F. Lentine t o H. R. Den to n,
" Zion Station Unit 1 Proposed Change to Facility Operating Licens e No. DPR-39. "
(b):
May 21, 1982, letter from F. Lentine t o H. R. Denton,
" Zion Station Unit 1, Cycle 7 Reload."
Dear Mr. Denton:
Commonwealth Edison hereby provides the additional information requested by the NRC in the May 24 and May 27, 1982 discussions with our personnel.
The following discussion addresses the most limiting total peaking factor (Fg) which could occur during Zion Unit 1, Cycle 7 (Re ference (b)).
A complete Westinghouse FAC analysis was performed for the full range of power distributions, including load follow maneuvers *, which are allowable under the operational strategy o f.
Constant Axial Offset Control (CAOC) embodied in the Zion Technical Specifications.
The results o f this F AC analysis showed that the highest total peaking factor (Fg) which could occur during Zion-Unit 1, Cycle 7 is 2.091.
Because this value is below the revised LOC A Fg limit of 2.13 due to steam generator tube plugging (Reference (a)), axial power distribution type surveillance is not required for Cycle 7.
- Note thet load follow maneuvers are currently prohibited per the NRC Order o f February 29, 1980.
8206070281 820602 PDR ADDCK 05000295 P
H. R. Denton Jun e 2, 1982 Additional information on the various classes o f non-LOC A transients and accidents was also requested.
Accidents which increase or decrease the heat removal by the secondary system are less severe at the current plugging level because of the reduced heat transfer between the primary and secondary system.
Those acci-dents which decrease the reactor coolant system flow rate, which involve reactivity and power distribution anomalies, and which increase or decrease the reactor coolant inventory (except LOCA),
contain suf ficient margin to o ffset the e ffect of tube plugging at the 4% level.
The effects of plugging on heat transfer area and primary coolant temperatures are offset by the approximately 9%
margin between actual flow and thermal design flow as well as the conservatism in the steam generator heat transfer analysis.
Based on this evaluation, suf ficient margin exists in the analysis of all non-LOCA accidents and transients to offset the ef fect of the 4% plugging level.
Please address any questions you may have to this office.
Very truly yours, F. G.
Lentine Nuclear Licensing Administrator 1m 4259N