ML20065T084

Advises That Util Evaluating & Will Incorporate Listed Enhancements,Per C-E Reassessment of Loss of Coolant EOPs in Response to Generic Ltr 89-19

ML20065T084
Person / Time
Site:	Calvert Cliffs
Issue date:	12/17/1990
From:	Creel G BALTIMORE GAS & ELECTRIC CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
REF-GTECI-A-47, REF-GTECI-SY, TASK-A-47, TASK-OR GL-89-19, NUDOCS 9012270120
Download: ML20065T084 (2)

Text

'

A B ALTIMORE '

GAS AND ELECTRIC CHARLES CENTER

• P.O. BOX 1475

• DALTIMORE, MARYLAND 21203 1475 Gtonot C Cnttu vict 9.cs t.c.a Nvetr ap Chtsov n w sw. s, December 17,19(X)

U. S. Nuclear Regulatory Commis.. ion Washington, DC 20555 NITENTION: Document Control Desk

SUBJECT:

Calvert Cliffs Nuclear Power Plant Unit Nos.1 & 2, Docket Nos. 50 317 & 50-318 Follow-up Response to Generic I etter 89-19. Unresolved Safety issue A-47

REFERENCES:

(a) Generic Letter 89-19. Request for Action Related to Unresolved Safety Issue A 47, Safety implications of Control Systems in LWR Nuclear Power Plauts" Pursuant to 10 CFR 50.54(f)

(b) Letter from Mr. G. C. Creel (BG&E) to NRC Document Control Desk, dated March 19, 1990, Response to Generic Letter 8919, Unresolved SafetyIssue A-47 Gentlemen:

In our initial response to Generic Letter 89-19, we stated that our Emergency Operating Procedures (EOPs) would be reassessed to ensure that operators can handle the spectrum of possible small break loss-of coolant-accidents. The assessment is complete. The final report from Combustion Engineering Owners Group showed that Loss of Coolant Emergency Operating Procedure (EOP-5) is adequate and no changes were required. The report did, however, recommend several enhancements to the procedure:

+ Enhancements to the Safety Function Status Check (SFSC)

- Include use of the Reactor Vessel Level Monitoring System to verify other indications that the core is covered.

- Include notes to explain that during Reactor Coolant Sgtem two-phase natural circulation Dow, the requirement for 10 F to 50 F(T-hot minus T cold)is not indicative of core Dow.

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Document Control Desk

, December 17,1990 Page 2

- Include notes to explain that the upper limit of 900 psia for Steam Generator (S/G)

Pressure Control does not consider that the S/G may be steaming through safety vaives at pressures greater than 1000 psia.

+ Include isolation of unneeded primary systems as a separate step and accomplished as a primary action.

+ Include a graph which indicates the amount of make up water needed (based on the decay heat rate and expected time to initiate shutdown cooling).

These enhanecments are being evaluated and will be incorporated in the EOPs, as appropriate, as part of our ongoing Procedure Upgrade Program.

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

Very truly yours, O / ^

^

/

GCC/JMO/ dim cc: D. A. Brune, Esquire J. E. Silberg, Esquire R. A. Capra, NRC I D. G. Mcdonald, Jr., NRC T. T. Martin, NRC L E. Nicholson, NRC R, I, McLean, DNR l

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