ML20078R799
| ML20078R799 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 12/19/1994 |
| From: | Denton R BALTIMORE GAS & ELECTRIC CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9412270253 | |
| Download: ML20078R799 (2) | |
Text
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w ROBERT E. DENTON Baltimore Gas and Electric Company Vice President Calvert Cliffs Nuclear Power Plant Nuclear Energy 1650 Calvert Cliffs Parkway Lusby, Maryland 20657 410 586-2200 Ext.4455 Local 410 260-4455 Baltimore December 19,1994 l
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 Response to Request by the NRC Staff to Use the Calvert Cliffs Nuclear Power Plant. Unit No.1. Probability Risk Assessment Data
REFERENCE:
(a)
Letter from Mr. D. G. Mcdonald, Jr. (NRC) to Mr. R. E. Denton (BGE),
dated April 20,1994, "Use of the Calvert Cliffs Nuclear Plant, Unit 1, Probability Risk Assessment Data by the NRC Staff' In Reference (a), you requested that we voluntarily provide Probability Risk Assessment (PRA) data for inclusion in the Nuclear Regulatory Commission (NRC) " library" of plants. We support the NRC program which we understand will use plant-specific PRA data to evaluate significant events, resolve generic safety issues and respond to "what if" type questions. Its potential benerits to the NRC and the Nuclear Industry are evident. We would like to participate in the program starting in mid-1996. Between now and early 1996, our PRA model will be undergoing a numbei of upgrades after which we expect our PRA data will become more stable. We suggest that it would be wasteful for the NRC staff to load current Calvert Cliffs PRA data and then find that the NRC model was not consistent with our model.
The following reasons support our decision to defer participating in the program until mid-1996:
The current PRA credits no modifications completed since 1992. A number of significant plant modifications, including the new Emergency Diesel Generators, will be completed by 1996 and, therefore, credited in the PRA. Currently, we anticipate fewer significant plant modifications after 1996 and, therefore, expect the PRA to become more stable.
Maintenance rule indicator development has necessitated some modeling changes and data
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upgrades to our PRA.
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i.3, Document Control Desk
' December 19,1994 I
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During discussions with the NRC contractor, we learned that considerable NRC rework was required when one plant upgraded their PRA while the contractor was loading the earlier PRA l
data.
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During subsequent discussions, the NRC contractor informed us that the size of our PRA may exceed the capability of the NRC's software.
We would like to be kept apprised of the status of the NRC's program. We are especially interested in knowing if the capability of the NRC software is consistent with the size of our PRA.
Should you have any questions regarding this matter, we will be pleased to discuss them with you.
Very truly yours,
[
RED /JM0/bjd I
cc:
D. A. Brune, Esquire J. E. Silberg, Esquire L. B. Marsh, NRC D. G. Mcdonald, Jr., NRC T. T. Martin, NRC i
P. R. Wilson, NRC R. I. McLean, DNR J.11. Walter, PSC
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