ML20211E817
| ML20211E817 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 10/22/1986 |
| From: | Mihalcik J BALTIMORE GAS & ELECTRIC CO. |
| To: | Thadani A Office of Nuclear Reactor Regulation |
| References | |
| FCM-86-256, NUDOCS 8610230210 | |
| Download: ML20211E817 (1) | |
Text
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BALTIMORE GAS AND ELECTRIC CHARLES CENTER. P.O. BOX 1475 BALTIMORE, MARYLAND 21203 NUCLEAR ENGINEERING SERVICES DEPARTMENT '
CALVERT CUFFS NUCLEAR POWER Pf_ ANT LUS8Y. MARYLAND 20657 October 22,1986 FCM 86-256 Y./
L L
Mr. Ashok C. Thadani, Director PWR Project Directorate #8 Division of PWR Licensing-B -
U.S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation Washington, D.C. 20555
SUBJECT:
Moderator Temperature Coefficients for Unit 1 Cycle 9 and Unit 2 Cycle 8
REFERENCE:
(1) 3.A. Tiernan to A.C. Thadani letter dated July 31,1986, "Calvert Clifis Nuclear Power Plant Unit Nos.1 & 2; Docket Nos. 50-317 &
50-318; Request for Amendment", six changes including Moderator Temperature Coefficient (2) BG&E/C-E Presentation to NRR on 24-Month Cycles at Bethesda, October 1,1986 Mr. Thadani:
In Reference (1), BG&E requested a modification to Technical Specification 3.1.1.4 concerning moderator temperature coefficient (MTC). Prior to this submittal all safety analyses with the exception of Feed Line Break addressed positive temperature -
coefficients at least as high as +.5.
With this submittal, the most limiting Feed Line Break was evaluated to show that a +.5 MTC is acceptable at 100% power.
This submittal requested changing the 100% limit to +.5.
At our meeting (Reference (2)) some concern was expressed about positive MTC effect on the generic ATWS assumptions. In the future we plan to. address the generic ATWS implications, if any. For the interim period, it should be noted that the upcoming Unit 1 Cycle 9 and Unit 2 Cycle 8 reactor core designs are based on a less than 0 MTC at 100%
power and equilibrium xenon conditions, assuming the expected cycle lengths are realized for the operating cycles.
f O v n.
- 3. A. Mihalcik Fuel Cycle Management JAM /Imt h6 8610230210 % 02gl7 t) )
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