ML19254B081

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Forwards Response to IE Bulletin 79-06C, Nuclear Incident at TMI - Suppl. Describes Actions to Be Taken
ML19254B081
Person / Time
Site: Farley Southern Nuclear icon.png
Issue date: 08/28/1979
From: Clayton F
ALABAMA POWER CO.
To: James O'Reilly
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
NUDOCS 7909240243
Download: ML19254B081 (4)


Text

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Alabama Power Company i 600 North 18th Street n

  • Post Office Box 2641 I Birmingham, Alabama 35291 Telephone 205 323-5341
  • c3NRC F F. L CLAYTON. J A. * I ' i d '

Senior Vice President AlabamaPower

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j t q 'y August 28, 1979 Docket No. 50-348 Mr. James P. O'Reilly, Director U. S. Nuclear Regulatory Commission Region II - 101 Marietta Street, N. W.

Suite 3100 Atlanta, Georgia 30303

Dear Mr. O'Reilly:

Enclosed is Alabama Power Company's response to I.E. Bulletin 79-06C, " Nuclear Incident at Three Mile Island - Supplement".

Yours very truly, b

F.L.Clayto(, Jr FLCjr/HRF/mmb Enclosure cc: Mr. R. A. Thomas Mr. G. F. Trowbridge Director, Office of Inspection & Enforcement )

Director, Office of Nuclear Reactor Regulation)

Washington, D. C. 20555

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OrbETAL COPY

A APC0 RESPONSE TO IE EULLETIN '9-06C Short-Term Actions ,

1. In the interim, until the design change required by the long-term action of this Balletin has been incorporated, institute the following actions at your facilities:

A. Upon reactor trip and initiation of HPI caused by low reactor coolant system pressure, immediately trip all operating RCPs.

Response

Appropriate emergency operating procedures have been revised to reflect immediate reactor coolant pump trip on reactor trip and initiation of HHSI caused by low reactor coolant system pressure.

B. Provide two licensed operators in the control room at all times during operation to accomplish this action and other immediate and follow-up actions required during such an occurence. For facilities with dual control rooms, a total of three licensed operators in the dual control room at all times meets the require-ments of this Bulletin.

Response

Two licensed operators will be in the Farley Nuclear Plant control room at all times while one unit is in mode 1 or 2.

When two units are both in either modes 1 or 2, three licensed operators will be in the control room at all times. FNP has a dual control room.

2. Perform and submit a report of LOCA analyses for your plants for a range of small break sizes and a range of time lapses between reactor trip and pump trip. For each pair of values of the parameters, determine the peak cladding temperature (PCT) which results. The range of values for each parameter must be wide enough to assure that the maximum PCT or, if appropriate, the region containing PCTs greater than 2200 degrees F is identified.

Response

A series of Loss of Coolant Accident (LOCA) analyses for a range of break sizes and a range of time lapses between initiation of break and pump trip applicable to the 2, S and 4 loop plants has been performed b~y the Westinghouse Owners' Group. A report summarizing the results of the analysis of delayed Reactor Coolant Pump trip during small loss of coolant accidents for the Westinghouse NSSS will be submitted to Mr. D. F. Ross by Mr. Cordell Reed on August 31, 1979. In the report, maximum PCT's for each break size con-sidered and pump shutoff times will be provided. The report concludes that if the reactor coolant pumps are tripped prior to the reactor coolant

' system pressure reaching 1250 psia, the resulting peak clad temperatures are less than or equal to those reported in the FSAR.

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'In addition, it is shown that there is a finite range of Break sizes and RCP trip times in all cases 10 minutes or later, which will result in PCT's in excess of 22000F as calculated with conservative Appendix K models. The operator in any event would have at least 10 minutes to trip the RCP's following a small break LOCA, especially in light of the conservatisms in the calculations. This is appropriate for manual rather than automatic action, based on the guidelines for termination of RCP operation presented in WCAP-9600.

3. Based on the analyses done under Item 2 above, develop new guidelines for operator action, for both LOCA and non-LOCA transients, that take into account the impact of RCP trip requirements. For Babcock & Wilcox designed reactors, such guidelines should include appropriate require-ments to fill the steam generators to a higher level, following RCP trip, to promote natural circulation flow.

Response

The Westinghouse Owners' Group has developed guidelines which were submitted to the NRC in Section 6 and Appendix A ef WCAP 9600. The analyses provided as the response to Item 2 are consistent with the guidelines in WCAP 9600. No changes to these guidelines are needed for both LOCA and non-LOCA transients.

4. Revise emergency procedures and train all licensed reactor operators and senior reactor operators based on the guidelines developed under Item 3 abeve.

Response

The Owners' Group effort to revise emergency procedures covers many issues, including operation of the Reactor Coolant Pumps. The action taken in response to Item 1 is sufficient as an interim measure. The expected schedule for revising the LOCA, steamline break and steam generator tube rupture emergency procedures is the following:

Mid-October: Guidelines which have been reviewed by the NRC will be provided to each utility. Appropriate utility personnel associated with writing procedures will meet with the Owners' Group Subcommittee on Procedures and Westinghouse to provide the background for revising their emergency procedures.

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1 to 2 months )

from: Mid- ) Plaat specific procedures will be revised.

October )

3 to 4 mo..ths )

f ron Mid- -) Revised procedures will be implemented and operators October ) trained.

5. Provide analyses and cavalop guidelines and procedures related to in-adequate core cooling (se discussed in Section 2.1.9 of NUREG-0578, "TMI 2 Lessons Learned Task Force Status Report and Short-Term Recom-mendations") and define the conditions under which a reerart of the RCPs should be attempted.

Response

Analyses related to inadequate core cooline and definition of con-ditions under which a restart of the RCP's should be attempted will be performed. Resolution of the requirements for the analyses and an acceptable schedule for providing the analyses and guidelines and procedures resulting from the analyses will be arrived at between the Westinghouse Owners' Group and the NRC ataff.

Long-Term Action m

1. Propose and submit a design which will assure automatic tripping of the operating RCPs under all circumstances in which this action may be needed.

Response

' Long Term

,, As discussed in our response to short-tern Item 2, we do not believe i that automatic tripping of the RCP's is a required function based on the analyses that have bcen performed and the guidelines that h9ve been developed for manual RCP tripping. We propose that this item chauld be discussed with the NRC staff following their review of the Owners' Group Submitt.31.

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