ML20094C284
| ML20094C284 | |
| Person / Time | |
|---|---|
| Site: | Fermi  |
| Issue date: | 07/31/1984 |
| From: | Jens W DETROIT EDISON CO. |
| To: | Youngblood B Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-2.K.3.18, TASK-TM EF2-66712, NUDOCS 8408070440 | |
| Download: ML20094C284 (2) | |
Text
.D Wayne H Jens Vo Pres $mt Nucl ear Opo<* om Detroit cec ne a.4 symy (313) 5 415 July 31, 1984 EF2-66712 Director of Nuclear Reactor Regulation Attention:
Mr. B.
J.
Youngblood, Chief Licensing Branch No. 1 Division of Licensing U.
S.
Nuclear Regulatory Commission Washington, D.
C.
20555
Dear Mr. Youngblood:
Reference:
(1) Fermi 2 NRC Docket No. 50-341 (2) Letter, Detroit Edison to NRC, " Schedule for Detroit Edison's Compliance with UUREG-0737, Item II.K. 3.18, ' ADS Logic Modification'", EF2-56943, April 26, 1982 (3) Letter, T. J.
Dente to D.
G.
- Eisenhut, "NUREG-0737 Item II.K. 3.18, Modification of Automatic Depressurization System Logic", BWROG-8260, dated October 28, 1982 (4 ) NUREG-0519, Supplement 5,
" Safety Evaluation Report Related to the Operation of LaSalle County Stations, Units 1 and 2",
Page 22-8, August, 1983 (5) NUREG-0991, " Safety Evaluation Report Related to the Operation of Limerick Generating Station, Units 1 and 2",
Page 15-25, August, 1983
Subject:
Modifications of ADS Logic (NUREG-0737, Item II.K.3.18)
The BWR Owners Group submitted, via Reference 3, a report which identified ADS logic modifications intended to address both the NUREG-0737 requirements and the ATWS consideration.
Detroit Edison notified the NRC in Reference 2 and a revision to FSAR Appendix H.II, Item H.II.K.3.18 that any commitment to the BWROG-proposed ADS modificaticns would be provided only af ter the NRC had both completed its review of Reference 3 and documented its recommendations.
As a result of the NRC approval of Option 4 of Reference 3 on -the LaSalle and Limerick dockets (References 4 and 5, respectively), Edison has decided to similarly implement kB i
BM'8070440 840731 PM ADOCK 05000341 A
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A 4
July 31~, 1984 t-Mr. B.
J. Youngblood EF2-66712 Page 2
- Option 4.
Implementation will involve the installation of an ADS manual inhibit switch, in conjunction with a timer which will bypass.the high drywell pressure permissive signal after a sustained low water level indication.
Edison has initiated the required design work, but due to the long lead delivery times from General Electric and the current advanced status of the preoperational test program, Edison is.rciterating its previous commitment (see Reference 2) to complete the required. modification by completion of the first refueling outage.
It-is obviously highly desirable to keep any modifications to the plant-to a minimum during the preoperational and startup testing phase.
In addition, alterations to ECCS logic should not be " rushed" until the full impact of such 6
- changes can be understood.
As you are aware, such changes also involve changes.in Emergency Operating Procedures and training.
Until such time that the alterations are made,
- adequate justification for interim operation is provided by the past operating history of BWR's and the fact that, as stated in Reference (3), the current ADS logic design together with the symptom based Emergency Procedures satisfies the intent'of NUREG-0737, Item II.K. 3.18 in that this combination provides additional assurance of adequate
' core cooling for LOCA events which do not directly produce a high drywell pressure signal.
Please adviselof any additional plant unique information that may be required to support your review of this issue.
If you have any questions, please contact Mr. Keener Earle at (313) 586-4211.
M Sincerely,
/
l '1 (44d.
cca Mr.
P.
M. Byron Mr.'M.
D.
Lynch USNRC, Document. Control Desk Washington, D.
C.
20555
/
_.