ML20057B241
| ML20057B241 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 09/14/1993 |
| From: | Denton R BALTIMORE GAS & ELECTRIC CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| IEB-88-011, IEB-88-11, TAC-M72119, TAC-M72120, NUDOCS 9309200205 | |
| Download: ML20057B241 (4) | |
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4 B ALTIMORE g GAS AND {
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1650 CALVERT CUFFS PARKWAY. LUSBY, MARYLAND 20657-47C2 ROBERT E. DENTON VICE PRE $tDENT NUCLEAR ENERGY fac)peo 44?t September 14,1993 U. S. Nuclear Regulaiory Commission War.hington, DC 20555 ATFENTION:
Document Control Desk
SUBJECT:
Calvert Cliffs Nuclear Power Plant Unit Nos.1 & 2; Docket Nos. 50-317 & 50-318 Response to Safety Evaluation For Combustion Engineering Owners Group Report CLN-387-P, Revision 1,
" Pressurizer Surge Line Thermal Stratification Evaluation," NRC Bulletin 88-11 (TAC Nos. M72119 and M72120)
Nuclear Regula:ory Commission Bulletin 88-11 requested that we establish and implement a
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program to confirm pressurizer surge line integrity in view of thermal stratification issues.
Attachment (1) discusses our interim tesponse to the three actions requested by the Safety Evaluation Report (SER) on the Combustion Engineering Owners Group (CEOG), [ Reference (i)].
Following receipt of the SER, we were informed by Combustion Engineering that Task 6%, " Surge Line Design Report Addenda" would not be completed to incorporate the results of the SER until November 30,1993. Wc cannot complete our review of actions recommended by the bulletin until Task 6% is finalized. We plan to complete these actions within 60 days of the receiving the final report of Task 696. " Surge Line Design Repoit Addenda" (i.e., approximately January 31,1994).
Should you have any further questions regarding this matter, we will be pleased to discuss them with you.
Very truly yours,
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S e6 for R. E. Denton Vice President - Nuclear Energy RED /JMOTjmo/bjd Attachment NRC Bulletin 88-11, " Pressurizer Surge Line Thermal Stratification" Response to SER dated July 12,1993,:
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sent Control Desk DocuInber 14,1993 Septt Page 2 cc:
D. A. Brune, Esquire J. E. Silberg, Esquire R. A. Capra, NRC D. G. Mcdonald, Jr., N RC T. T. Martin, NRC P. R. Wilson, NRC R. I. McLean, DNR J. H. Walter, PSC Dr. B. T. Lubin, Ph.D, CE 1
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Docur ient Control Desk Septepher 14,1993
.Page 3
REFERENCES:
(a)
Pressurizer Surge Line Thermal Stratification (NRC Bulletin 88-11),
dated December 20,1988 (b) letter from Mr. G. C Creel (BG&E) to Document Control Desk (NRC), dated March 3,1989, "NRC Bulletin 88-11, Pressurizer Surge Line Thermal Stratification" (c)
Letter from Mr. G. C. Creel (BG&E) to Document Control Desk (NRC), dated June 6,1989, "NRC Bulletin 88-11, Pressurizer Surge Line Thermal Stratification" (d)
Letter from Mr. G. C. Creel (BG&E) to Document Control Desk (NRC), dated July 31,1989, "NRC Bulletin 88-11, Pressurizer Surge Line Thermal Stratification" (e) letter from Mr. D. G. Mcdonald (NRC) to Mr. G. C Creel (BG&E), dated July 18,1990, "NRC Palletin 88-11, " Pressurizer Surge Line Thermal Stratification-r.haluation of Combustion Engineering Owners Group Bounding Analysis Relating to Calvert Cliffs, Units 1 and 2, TAC 72119 (Unit 1) and 72120 (Unit 2)"
(f)
Letter from Mr. D. G. Mcdonald (NRC) to Mr. G. C Creel (BG&E), dated August 14,1991, " Pressurizer Surge Line Thermal Stratification,Bulletin 88-11, Calvert Cliffs Nuclear Power Plant, Unit 1 (TAC No. 72119) and Unit 2 (TAC No. 72120)"
(g)
Letter from Mr. D. G. Mcdonald (NRC) to Mr. G. C Creel I
(BG&E), dated September 9,1991," Pressurizer Surge Line Thermal Stratification,Bulletin 88-11, Calvert Cliffs Nuclear Power Plant, Unit 1 (TAC No. 72119) and Unit 2 (TAC No. 72120)"
(h)
Letter from Mr. G. C Creel (BG&E) to Document Control Desk (NRC), dated December 24,1991, " Pressurizer Surge Line Thermal Stratification,Bulletin 88-11 Calvert Cliffs Unit 1 - and 2 (TAC Nos. M72119 and M72120)"
f (i)
Letter from Mr. D. G. Mcdonald (NRC) to Mr. G. C Creel (BG&E), dated July 12,1993, " Safety Evaluation For Combustion l
Engineering Owners Group Report CEN-387-P, Revision 1,
" Pressurizer Surge Line Thermal Stratification Evaluation,"
(Bulletin 88-11), Calvert Cliffs Nuclear Power Plant, Unit 1 (TAC No. 72119) and Unit 2 (TAC No. 72120)"
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ATTACIIMENT 0)
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NRC llULLETIN 88-11, PRESSURIZER SURGE LINE TIIERMAL STRATII'ICATION, RESPONSE TO SER, dated July 12,1993 I
l The subject SER requested three actions:
i (1)
"Please venfv the applicability of the CEOG bounding analysis in CEN-387-P, Revision 1, to the
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Calvert Cliffs Nuclear Power Plant, Unit Nos. I and 2."
RESPONSE
The CEOG bounding analysis in CEN-387-P, Revision 1 is applicable to Units 1 and 2. Data used in their analysis was collected from Calvert Cliffs Unit 1. Our review of the Unit 1 plant data shows that all differential temperatures were less than 200 degrees F, which is below the 340 degrees used in the CEOG analysis. In only four of the thirty heatup and cooldown evolutions where the data was collected did the differential temperature exceed 110 degrees F. In all other cases, the differential temperature was 110 degrees F or less. The geomenies of Units 1 and 2 were also considered in determining the bounding plant-geometry. Since the operating practices and geometries of Unit I and 2 are similar, the analysis applies to both units.
(2)
"In addition, please confirm that all actions required by Bulletin 88-11, including the updating of the plant-specific stress andfatigue analyses required by Action 1.d, have been completed."
RESPONSE
i This item can not be completed until 60 days after we receive the final documentation of CEOG Task 696, " Surge Line Design Report Addenda." We expect to receive the final report from Combustion. Engineering in November 1993. We will send you our final response to this item 60 days after we receive the final report of Task 696.
(3)
.. the staff concurs with BNL's lBrookhaven National Laboratory] recommendation for performing enhanced inservice inspection to provide additional confidence in the structural 7
integrity of the surge lines. Therefore, the staff recommends that licensees perform volumetric e
examination of critical elbow components as part of future ASME Section XI inservice examinations. Examinations of elbow bodies, as well as elbow welds, should beperformed to ensure that the most highly stressed areas have not sustained damage... you may implement the i
recommendation on a voluntary basis.*
RESPONSE
We are deferring a decision on whether to perform the voluntary inspections until ASME Section XI guidelines for volumetric examinations of components are established. After guidelines are adopted by the ASME code, we will determine the extent, if any, ofinspections to be conducted.
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