ML20070T721

Application for Amends to Licenses DPR-53 & DPR-69,modifying Definition 1.8,Item 1.8.3 & Surveillance Requirement 4.6.1.1.b of Tech Specs Re Containment Integrity

ML20070T721
Person / Time
Site:	Calvert Cliffs
Issue date:	04/02/1991
From:	Creel G BALTIMORE GAS & ELECTRIC CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20070T723	List: ML20070T721 ML20070T728
References
NUDOCS 9104050070
Download: ML20070T721 (4)

Text

e B A LTIMORE GAS AND ELECTRIC CHARLES CENTER e P.O. BOX 1475

• BALTIMORE, MARYLAND 21203-1475 Gromot C CRtto v:ce e.c ocie April 2,1991 w a..cu.c, m.,,. n. u.

U. S. Nuclear Regulatory Commission Washington, DC 20555 ATTENTION:

Document Control Desk

SUBJECT:

Calvert Cliffs Nuclear Power Plant Unit Nos.1 & 2: Docket Nos. 50 317 & 50-318 1.icensg_ Ame,ndment Request: Containment intetrity Definition Gentlemen:

The Baltimore Gas and Electric Company hereby requests an Amendment to its Operating License Nos. DPR 53 and DPR 69 for Calvert Cliffs Unit Nos.1 & 2, respectively, with the submittal of the proposed changes to the Technical Specifications. This change would clarify the definition of containment integrity to eliminate an apparent conflict of action requirements.

DESCI(IPTION The proposed amendment would modify Definition 1.8, item 1.8.3, and Surveillance Requirement 4.6.1.1.b of the Calvert Cliffs, Units 1 and 2 Technical Speci0 cations to indicate that the impact of the containment air locks on containment integrity is based on compliance with Specif4ation 3.6.1.3 (Containment Air Imcks). This would clarify that operation is required to be in accort..cc with the intended action requirements of Limitinr. Condition for Operation 3.6.1.3, rather than the action requirements of Limiting Condition for Operation 3.6.1.1.

IM KGl(OUND The Calvert Cliffs Unit 2 Technical Specifications, as originally issued, and the subsequent conversion of Unit 1 to the Standardized Technical Specification format, were written such that the De0nition and the Surveillance Requirement both require operable containment air locks to show containment integrity. In more recently issued Technical Speci0 cations for other nuclear power plants, the Definition and the Surveillance Requirement both ;cquire compliance with the requirements of Specification 3.6.1.3. " Compliance with the requirements of Specification 3.6.1.3" provides for operation within the action requirements to suffice for containment integrity. With the current Calvert Cliffs wording, the containment integrity specification requires shutdown (Mode 5) within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> and does not provide the intended out of-service time of the action statement of SpeciGcation 3.6.1.3 for attempting repair of the air locks prior to requiring shutdown.

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, Document Control Desk April 2.1991 Page 2 The Calvert Cliffs Technical Specifications are currently worded such that they impose an unintended and unnecessary restriction. Baltimore Gas and Electric (BG&E) Company requests that they be changed to reDect the wording of more recently licensed nuclear power plants.

HEOUESTED Cil ANGE Change pages 12 and 3/4 6-1 of the Unit I and Unit 2 Technical SpeciGeations as shown on the marked up pages attached to this transmittal.

SAHilY ANAINSES The containment uir locks form a part of the containment pressure boundary. As such, uir lock integrity and air tightness is essential to limit offsite doses from a Dusign Basis Accident (DBA) as described in the safety analysis. The DBAs which couH occur at power and result in a release of radioactive material within containment are a loss of coolant accident (LOCA), a main steam line break, and a control clernent assembly ejection accident. Each of these DBAs assumes that the containment (and its air locks)is capable of performing its intended containment function such that the release of fission products to the environment is limited to a vuy small fraction of the containment volume. These events are described in Updated Final Safety Analyses Report (UFSAR) Chapter 14.

The containment design provides for an allowable leakage rate (La) of 0.20% of the containment air weight per day. This leakage rate was used in the offsite radiological dose calculations for Calvert Cliffs and is the basis for Technical Specification 3.6.1.2.a. An additional restriction imposed by 10 CFR Part 50, Appendix J, and Technical Specification 3.6.1.2.b is that no more than 60% of this allowable leakage (L ) be through Type B and C penetrations. The air locks are Type B a

penetrations. Each containment air lock is further limited, by Technical Specification 3.6.1.3.b, to an overallleakage rate of 5% of the allowable leakage (L )-

a Both of the containment air locks are designed with a door on each end. Both doors are required to be closed during operation unless the air lock is being used for transit entry and exit through the containment. Then, at least one door is required to be closed. Each door contains a double seal.

The area between the doubic seal on a dcxir is maintained pressurized to provide the leakage barrier.

In accordance with Technical Specification Surveillance Requirement 4.6.1.3.a. the seal leakage of each containment air k)ck is routinely verified following its use to be no greater than 0.02% of the allowable containment leakage (La)-

The operable seal of either door is sufficient to maintain the required containment barrier since each is designed to withstand the peak containment pressure calculated to occur following a DBA however, both doors are kept closed when not in use to provide an additional barrier. Specification 3.6.1.3 was written to recognize this capability of a single door to serve as a leakage barrier and provided an allowed out-of ser ice time for one door in order to attempt repairs prior to requiring a shutdown. Ilowever, due to the wording by which the containment integrity requirements reference the air lock doors (stating that the doors must be operable), the intent to govern airlock doors with the action statements of Specification 3.6.1.3 is thwarted. Based on the design of the air lock doors, BG&E believes the containment integrity wording to be incorrect and unnecessarily restrictive.

Thus, we request that the wording be revised.

1 1

Document Control Desk i

April 2,1991

' Page 3 a

1)l,TEllM f NATION Q)' S1(rbl[ICANT llALillllS This proposed change has been evaluated against the standards in 10 CFil 50.92 and has been determined to involve no significant huards considerations, in that operation of the facility in accordance with the proposed amendment:

(1) li'ould not inwire a significant increase in the prvbability or consequences of an accidentpreviously evaluated.

'lhe containtnent air locks are not considered as initiators for any previously evaluated accident. This change does not impact their design and therefore does not significantly increase the probability that they would initiate any previously evaluated accident.

The safety analyses consider the containtnent leakage barrier to be intact and maintaining the leakage at less than the assumed value at the initiation of the evaluated accidents that occur during operation. Since each air lock door is designed to provide that containment barrier and is periodically tested to assure that leakage is not excessive, this change will not significantly increase the consequences of any previously evaluated accidents.

(2)

W<ndd not create the possibility of a new or different type of accident l rom any accident previously evaluated.

This change does not involve a change to the design of the plant. The new method of operation will not involve any components which could initiate un accident.

Therefore, this change would not create the possibility of a new or different type of accident from any accident previously evaluated.

(3)

Would not inwire a significant reduction in a margin of safety.

The margin of safety for the containment integrity technical specification is provided by assuring that the release of radioactive materials from the containment atmosphere will be restricted to those leakage paths and associated leak tales as:,umed in the accident analyses. Since cach air lock door is designed to provide that containment barrier, this change does not involve a significant reduction in the margin of safety.

Sfl1EI)UI,li 11G&E requests approval of this change by June 30,1991, While issuance of this amendment is currently not identthed as having an impact on outage completion or continued plant operation, your prompt consideration is appreciated.

S311ECOMh.llT[EE ItINIIM These proposed changes to the Technical Specifications and our determination of significant hazards have been reviewed by our Plant Operations and Off Site Safety 1(eview Committees, and they have

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, Documc it Control De*L April 2, W91 Page 4 concluded that implementation of these changes will not result in an undue risk to the health and safety of the publit..

Yery truly yours, 77)

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STATE OT MARYLAND t t

TO WIT t COUNTY Or CALVERT I hereby certify that on ttm 2 day of _

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,1991,be re m the subscriber, a Notary Public of the State of Maryland in'and for Calocc) osm d/

pen, anally appeared George C. Creel, being duly sworn, and states that he is Vice President of the Baltimore Gas and Electric Cornpany, a corporation of the State of Maryland; that he provides the foregoing response 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 response on behalf of said Corporation.

WITNESS mylland and NotarialScal:

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Notary Public My Comrnission Expires:

AMy ch. /9 Dafe GCC/ ERG / erg /dtm

Attachment:

(1)

Markup of Unit I and 2 Technical Specification Pages 12 and 3/4 6-1 cc:

D. A.11rene, Esquire l

J. E. Silberg, Esquire R. A. Capra, NRC D. G. Mcdonald, Jr., N RC T. T. Martin, NRC L E. Nicholson. NRC R. I. McLean, DNR l

J. II. Water, PSC l

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