LIC-99-0037, Responds to NRC 990126 RAI Re GL 97-01, Degradation of CRDM Nozzle & Other Vessel Closure Head Penetrations. Response Confirms with NRC & NEI Recommendations to Utilize Generic Industry Response to Issue

Responds to NRC 990126 RAI Re GL 97-01, Degradation of CRDM Nozzle & Other Vessel Closure Head Penetrations. Response Confirms with NRC & NEI Recommendations to Utilize Generic Industry Response to Issue

ML20206C668
Person / Time
Site:	Fort Calhoun
Issue date:	04/26/1999
From:	Phelps R OMAHA PUBLIC POWER DISTRICT
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
GL-97-01, GL-97-1, LIC-99-0037, LIC-99-37, NUDOCS 9905030137
Download: ML20206C668 (4)

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BMB Onahs P#cPonetwct ett sous tah sontuna Onahn, Nebraska 68172247 April 26,1999 LIC-99-0037 U.S. Nuclear Regulatory Commission Attn: Document Control Desk ,

Mail Station P1-137 Washington, D.C. 20555-0001 1

References:

1. Docket No. 50-285

2. NRC Generic Letter 97-01, " Degradation of Control Rod Drive Mechanism Nozzle and Other Vessel Closure Head Penetrations," dated April 1,1997

3. Letter from OPPD (S. K. Gambhir) to NRC (Document Control Desk), l dated April 30,1997 (LIC-97-0065) l

4. Letter from OPPD (R. L. Phelps) to NRC (Document Control Desk), dated July 30,1997 (LIC-97-0123)

5. Letter from NRC (L. Raynard Wharton) to OPPD (S. K. Gambhir), dated January 26,1999

SUBJECT:

Response to Generic Letter 97-01, " Degradation of Control Rod Drive Mechanism Nozzle and Other Vessel Closure Head Penetrations," Request for AdditionalInformation On April 1,1997, the NRC issued Generic Letter (GL) 97-01, " Degradation of Control Rod Drive Mechanism Nozzle and Other Vessel Closure Head Penetrations." Omaha Public Power District (OPPD) responded to GL 97-01 in letters dated April 30,1997 and July 30,1997, Nuclear Energy Institute (NEI) Project Number 689, " Generic Responses to the NRC Requests for Additional Information on Generic Letter 97-01," produced by Dominion Engineering, was submitted under separate cover to the NRC on December 11,1998, by NEl. On January 26, 1999, the NRC issued a request for additionalinformation (RAI) to OPPD regarding the April 30, 1997 and July 30,1997 responses.

Attached is OPPD's response to the RAI for Fort Calhoun Station. Because of OPPD's industry participation, this response conforms with the NRC and NEl recommendations to uti'#.e the generic industry response to this issue.

Please contact Bob Lisowyj of my staff at 402-533-6491 if you have any questions.

Sincerely,

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[ 4.2 6 ff R. L. Phelps Division Manager Nuclear Engineering ,

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4' 9905030137 990426 DR ADOCK 050002 5 45 5124 Employ,nent witn EqualCpportunity

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U. S. Nuclear Regulatory Commission l LIC-99-0037 '. )

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~ Attachment DDD/ddd 4

c: E. W. Merschoff, NRC Regional Administrator, Region IV L. R. Wharton, NRC Project Manager

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W. C. Walker, NRC Senior Resident inspector Winston & Strawn s

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LIC-99-0037 Attachwant '.

Page 1 Omaha Public Power District (OPPD) Response to Generic Letter 97-01, " Degradation of Control Rod Drive Mechanism Nozzle and Other Vessel Closure Head Penetrations,"

Request for Additional information NRC RAl:

Designate which crack susceptibility modelis being endorsed for the assessment of CEDM penetration nozzles at yourplant.

OPPD Response:

Please refer to the Response to Question 1 included in Enclosure 4, "CEOG Response to NRC Requests for Additional Information," of the NEl December 11,1998, submittal.

NRC RAl:

Indicate how the susceptibility model being endorsed relates to the CEOG=s integrated program for assessing the CEDM penetration nozzles at ABB-CE designed plants, and whethat or not the design of the susceptibility modelis consistent with the contents of Topical Report CE NPSD-1085.

OPPD Response:

Please refer to the Response to Question 2 included in Enclosure 4, "CEOG Response to NRC

~ quests for Additional Information," of the NEl December 11,1998, submittal.

NRC RAl:

If the ABB-CE PITM modelis being endorsed for the assessment of CEDM penetration nozzles at Ft. Calhoun, address the items a. through e. that follow. If the Dominion Engineering susceptibility modelis being endorsed for the assessment of CEDM penetration nozzles at your plant (s), address the items f. through I. that follow.

OPPD Response:

Please refer to the Response to Question 1 included in Enclosure 4,"CEOG Response to NRC Requests for Additional Information," of the NEl December 11,1998, submittal. As stated therein, the CEOG now endorses the use of the EPRI model, produced by Dominion Engineering, for the assessment of primary water stress corrosion cracking in Alloy 600 reactor vessel head penetrations.

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' LIC-99-0037

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i NRC RAl: 1 If the Dominion Engineering susceptibility modelis being endorsed for the assessment of CEDM penetration nozzles at your plant (s), address the items f. through i. that follow. l

f. Provide a description of how the various product forms, material specifications, and heat treatments used to fabricate each CEDM penetration nozzle at the CEOG member utilities are handled in the Dominion Engineering susceptibility model.

OPPD Response:

Please refer to the Response to Question 3 included in Enclosure 4, "CEOG Response to NRC Requests for Additional Information," of the NEl December 11,1998, submittal.

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g. Provide any additionalinformation, if available, regarding how the model will be refined to allow the input of plant-specific inspection data into the model's analysis methodology.

OPPD Response:

Please refer to the Response to Question 5 included in Enclosure 4, "CEOG Response 1 to NRC Requests for Additional ififormation," of the NEl December 11,1998, submittal.

h. Describe how the Dominion Engineering crack initiation and crack growth models for assessing postulated flaws in vessel head penetration nozzles were benchmarked, and provide a listing and discussion of the standards the models were bench-marked against.

OPPD Response:

Please refer to the Response to Question 4 included in Enclosure 4 "CEOG Response to NRC Requests for Additional Information," of the NEl December 11,1998, submittal.

i. Provide the latest model susceptibility rankings of CEDM penetration nozzles in CEOG memberplants based on the resu;ls of the Dominion Engineering susceptibility model analyses of these CEDM and ICI nozzies.-

OPPD Response:

Please refer to the Response to Question 6 included in Enclosure 4 and detailed in Enclosure 1 of "CEOG Response to NRC Requests for Additional Information," of the ,

NEl December 11,1998, submittal. l l

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