ML20079D390

Application for Amends to Licenses DPR-53 & DPR-69,changing Tech Spec 3/4.2.1 Re Limiting Conditions for Operation & Surveillance Requirements for Linear Heat Rate for Consistency W/Design Basis in Topical Rept CEN-124(B)

ML20079D390
Person / Time
Site:	Calvert Cliffs
Issue date:	07/02/1991
From:	Creel G BALTIMORE GAS & ELECTRIC CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20079D391	List: ML20079D390 ML20079D392
References
NUDOCS 9107120222
Download: ML20079D390 (3)

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. B ALTIMORE GAS AND l ELECTRIC  !

( CHARLES CENTER

• P.O. BOX 1475

• BALTIMORE. MARYLAND 21203 1475 l

GcoRoE C CREEL l' v.c a Pat oc c.o NVCLE AR rhC AGv 1300 pe o.a a t t July 2,1991 U. S. Nuclear Regulato.y Commission Washington, DC 20555 l

ATTENTION: Document Control Desk l

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SUBJECT:

Calvert Cliffs Nuclear Power Plant l Unit Nos.1 & 2: Docket Nos 50-317 & 50-318 Revision to Technical Specification Bases Gentlemen:

The Baltimore Gas and Electri: Company hereby submits for your information and distribution the attached revision to the Bases for the Technical Specifications provided with Operating License l Nos. Di'R-53 and DPR-69 for Calvert Cliffs Unit Nos.1 & 2, respectively.

l Technical Specification N4.2.1 provides limiting conditions for operation and surveillance requirements for the linear heat rate. Surveillance kequirement 4.2.1.2 requires that linear heat rate l

be determined to be within its limits by continuously monitoring the core power distribution with l cither the excore detector monitoring system or with the incore detector monitoring system.

l Normally, the incore detectors are used via the plant computer to monitor linear heat ra'e directly.

!' However, when the plant computer is not in senice, the excor, detectors are used in conjunctica with the power ratio recorder (PRR) to moniar axial shape index (ASI) as a function of thermal

_ power in order L assure operation within the limiting conditions for operation for linear heat rate.

There are six excore detector channels. Four safety channels (A, B, C, and D) provide inputs to the reactor protection system (RPS) and two control channels (X and Y) are part of the reactor regulating system. The X and Y control channels each have an upper and lower excore detector which provide input to the PRR. The PRR uses the difference between the upper and lower detector signals from the control channels to produce an ASI signal. Ilowever, the BASES for

, Specification 3/4.2.1 indicate that ASI is monitored "with the OPERABLE quadrant symmetric I

excore neutron flux detectors . . . ." The quadrant symmetric excore detectors are safety channels A, B, C and D, and are not the control channel excore detect rs used to monitor ASI.

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Documcot Control Desk July 2,1991

- Page 2 Baltimore Gas and Electric has therefore revised page B3/4 2-1 of the Bases for the Unit 1 and Unit 2 Technical Specifications as shown on the marked-up pages attached to this transmittal. These changes are consistent with the existing design basis for the facility as documented in Topical Report CEN.124(B) P, Part 3, hiarch 1980, " Statistical Combination of Uncertainties," which addresses this rnode of operation in Section 2.4 and Appendix A. Use of this topical report is induded in the Updated Final Safety Analysis Report (UFSAR), Section 3.5.3, and was approved in the NRC Safety Evaluation Reports (SER) for Calvert Cliffs Operating License Amendment Nos. 71 (Unit 1, SER Sections 5.4 and Appendix A, Section A.3.1) and 61 (Unit 2, SER Section 7.4).

As indicated above, these revisions for the Bases of the Technical SpeciGeations correct discrepancies in the existing Bat.es Section. These revisions rencet the existing design basis for the facility as documented in the UFSAR and design modifications previously approved by the NRC Staff. Further, these revisions have been reviewed by our Plant Operations and Safety Review Committee and Off-Site Safety Review Committee, and they have concluded that implementation of these revisions will not result in an undue risk to the health and safety of the public.

Should you have any questions regarding this matter, we will be pleased io discuss them with you.

Very truly yours, -

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6 STATE OF MARYLAND TO WIT /

COUNTY OF CALVERT l

l 1 hereby certify that on the 2 day of ,19 9/, before me, the subscriber, a Notary Public of the State of hlaryland fri and' for C%34d du< $ ,

personally appeared George C. Creel, being duly sworn, and states that he is Vice Pitsident of the Baltimore Gas and Electric Company, a corporation of the State of htaryland; that he provides the foregoing information for the purposes therein set forth; that the statements made are true and correct to the best of his knowledge, information, and belief; and that he was authorized to provide the information on behalf of said Corporation.

WITNI:SS my Hand and Notarial Scal: b Notary Public hiy Commission Expires: '

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GCC/ERGlerg/dlm

Attachment:

Revised Technical Specification Bases Pages Unit 1 - B3/4 2-1 Unit 2 - B3/4 2-1

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Document Control Desk July 2,1991 Page 3 cc: D. A.13 rune, Esquire J. E. Silberg, Erquire R. A. Capra, NRC D. O. Mcdonald, Jr., NRC T. T. Martin, NRC

1. E. Nicholson, NRC R.1. McLean, DNR J.11. Walter, PSC Y

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