ML20088A053
| ML20088A053 | |
| Person / Time | |
|---|---|
| Site: | Farley  |
| Issue date: | 04/03/1984 |
| From: | Clayton F ALABAMA POWER CO. |
| To: | Varga S Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-2.K.3.05, TASK-TM GL-83-10D, NUDOCS 8404100483 | |
| Download: ML20088A053 (3) | |
Text
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~ Memng Address.
Alteams Power Company -
600 North 18th Street Post Office Box 2641 i
Birmingham. Alabama 35291
-. Telephone 205 783-6081 i
F. L. Clayton Jr.
' Senior Vice President 4
Flintridge Building AlabamaPower thesouthem electncsystem April 3, 1984 t
L Docket Nos. 50-348 50-364 Director, Nuclear Reactor Regulation
. U. S. Nuclear Regulatory Commission Washington, D.C. 20555 Attention: Mr.: S. A. Varga
' Joseph M. Farley Nuclear Plant - Units 1 and 2 NUREG-0737, Item II.K.3.5 and Generic Letter 83-10d Gentlemen:
By letters of April 22 and December'22,1983, Alabama. Power Company presented the plan for demonstrating compliance with the criteria for resolution.of TMI Action Plan Requirement Item II.K.3.5.
These criteria were established in NRC Generic Letter 83-10d, dated February 8,1983, to
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all Licensees with Westinghou'se designed Nuclear Steam Supply Systems. The submittals which fulfill the established requirements have been transmitted to the NRC by Westinghouse Owners Group (WOG) letters 0G-110, dated December 1,1983 and 0G-117, dated March 12, 1984.
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Section I of the attachment to Generic Letter 83-10d discusses " Pump Operation Criteria Which Can Result in RCP Trip During Transients and Accidents". Subsection 1 of Section I presents guidelines for establishing l:
setpoints for RCP Trip.. The Westinghouse Owners Group response to this.
section of Generic Letter 83-10d has been incorporated into Revision 1 to the WOG Emergency Response Guidelines, which has been issued to member c uttlites. These guidelines will be incorporated into the Farley Nuclear Plant Emergency Response Procedures in accordance with Alabama Power Company's schedule to implement the provisions of Supplement 1 to i-NUREG-0737.
The RCP trip criteria being adopted in the Farley Nuclear Plant plant-specific' procedures-not only assures RCP trip for all losses of primary coolant for which trip is considered necessary but also permits RCP operation to continue during most non-LOCA accidents, including steam generator tube rupture events up to the design basis double-ended tube H_
rupture. The generic applicability of the RCP trip criteria selected has L
been documented by the.WOG report entitled, " Evaluation of Alternate RCP l
Trip Criteria"., which has been submitted to the NRC for review in letter
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8404100483-840403 PDR ADOCK 05000348 P
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- Mr.'S. A. Varga April 3, 1984 U. S. Nuclear. Regulatory Commission Page 2
. entitled " Justification of Manual RCP Trip for Small Break LOCA Events". As stated above,-these submittals completed the WOG documentation comprising a 1
generic = reply to Generic Letter 83-10d.
Subsection 2 of Section I of the attachment to Generic Letter 83-10d i
1 provides guidance for justification of manual RCP trip. Subsection 2a i.-
requires that compliance with 10CFR50.46 be demonstrated in an Appendix K small break LOCA analysis given that the RCPs are tripped two minutes after the onset of reactor conditions corresponding to the RCP trip setpoint. The WOG has ~ generically verified in the OG-117 submittal that predicted LOCA transients, assuming the two minute delayed RCP trip, are nearly identical to those presented in safety analysis reports utilizing the WFLASH evalt-ation model. Thus, the Final Safety Analysis Report for the' Farley Neclear Plant, which utilizes the WFLASH evaluation model, demonstrates Alabama Power Company's compliance with the Subsection 2a guidelines.
The WOG has also performed most probable, best estimate WFLASH analyses
'to demonstrate compliance with the guidelines presented in SuFsection 2b of Section l'of the attachment to Generic Letter 83-10d. These analyses lidentify that the minimum time available for operator action for the complete range of. LOCA break sizes exceeds the value contained in ANSI Standard N660; they show that RCPs may be tripped at any time during a LOCA event _ without resulting in excessive clad temperatures. The infomation presented in the generic report affirms the applicability of this best estimate analyses to the Farley Nuclear Plant; therefore, in combination
.with the Subsection 2a justification cited above, the best estimate analyses justify that manual RCP trip.is acceptable for the Farley Nuclear Plant when
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RCP trip setpoints consistent with Revision 1 to the Emergency Response Guidelines are in use.. Furthermore, the generic report demonstrates that no additional' contingency emergency response procedures are required to address the scenarios which may follow a missed RCP trip setpoint.
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. As referenced in Alabama' Power Company's April 22, 1983 letter to the NRC, wide range primary-system pressure is currently being utilized for the i
RCP trip setpoint. The acceptance ' criteria of this instrument is also discussed in the April 22,1983 letter. Alabama Power Company has subsequently reviewed the WOG criteria relating to RCP trip and has chosen L
subcooling as the variable for RCP trip. The acceptance criteria, which
-will. include instrumentation quality level, design features and_ degree of redundancy for this variable, have been addressed in Alabama Power Company's R.G? 1~.97 Compliance Report for Unit 2, dated March 30,1984 and will be
- addressed by.a lsimilar. report for Unit 1 in June 1984. The Farley Nuclear
- Plant training program instructs license candidates and licensed personnel to trip the RCPs in the event of a small break LOCA in accordance with the
' Farley Nuclear Plant Emergency Response Procedures. -This program will include use of subcooling as the criteria to trip RCPs upon incorporation of this criteria into existing Emergency Response Procedures.
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Mr. S..A. Varga April 3, 1984 U. S. Nuclear Regulatory Commission Page 3 In summary, the generic information presented by the WOG in the reports entitled " Evaluation of Alternate RCP Trip Criteria" and " Justification of Manual RCP Trip for Small Break LOCA Events" provides the response to Generic Letter 83-10d for-the Farley Nuclear Plant. The implementation of Revision 1 to the_WOG Emergency Resoonse Guidelines in the plant-specific emergency response procedures with an appropriate RCP trip setpoint specified resolves all issues associated with automatic tripping of the RCP s.-
If you have any questions, please advise.
Yours truly, F. L. Clayton, J(.
FLCJr/ JAR:grs-D32 cc: Mr. R. A. Thomas Mr. J. P. O'Reilly Mr. E. A. Reeves Mr. W. H. Bradford l
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