HNP-04-133, 60-Day Response to NRC Generic Letter 2004-01, Requirements for Steam Generator Tube Inspections
| ML043090488 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 10/28/2004 |
| From: | Morton T Progress Energy Carolinas |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| GL-04-001, HNP-04-133 | |
| Download: ML043090488 (3) | |
Text
? am CJ Progress Energy U.S. Nuclear Regulatory Commission OCT 2 8 2004 Serial: HNP-04-133 ATTENTION: Document Control Desk 10 CFR 50.54(f)
Washington, DC 20555 SHEARON HARRIS NUCLEAR POWER PLANT, UNIT NO. 1 DOCKET NO. 50-400/LICENSE NO. NPF-63 60-DAY RESPONSE TO NRC GENERIC LETTER 2004-01, "REQUIREMENTS FOR STEAM GENERATOR TUBE INSPECTIONS" Ladies and Gentlemen:
On August 30, 2004, the Nuclear Regulatory Commission (NRC) issued Generic Letter (GL) 2004-01, "Requirements for Steam Generator (SG) Tube Inspections," which requested licensees to provide information describing the SG tube inspections performed at their plant during the last inspection. If the SG tube inspection methods are not consistent with the NRC's position on inspection methods, then additional actions are requested. The GL requested this information within 60 days.
Attachment 1 provides the requested 60-day response to GL 2004-01 for the Harris Nuclear Plant (HNP).
Please refer any question regarding this submittal to Mr. Dave Corlett at (919) 362-3137.
I declare, under penalty of perjury, that the attached information is true and correct.
(Executed on OCT 2 8 2004
- Sincerely, Terry C. Morton Manager, Support Services TM/rgh
Attachment:
- 1. 60-Day Response to Generic Letter (GL) 2004-01, "Requirements for Steam Generator Tube Inspections" c:
Mr. R. A. Musser, NRC Senior Resident Inspector Mr. C. P. Patel, NRC Project Manager Dr. W. D. Travers, NRC Regional Administrator Progress Energy Carolinas, Inc.
Harris Nuclear Plant P.O. Box 165 New Hill, NC 27562
Attachment 1 to SERIAL: HNP-04-133 SHEARON HARRIS NUCLEAR POWER PLANT, UNIT NO. 1 DOCKET NO. 50400/LICENSE NO. NPF-63 60-DAY RESPONSE TO GENERIC LETTER (GL) 2004-01, "REQUIREMENTS FOR STEAM GENERATOR TUBE INSPECTIONS" Within 60 days of the date of this generic letter, addressees are requested to provide the following information to the NRC.
- 1. Addressees should provide a description of the SG tube inspectionsperfonned at their plant during the last inspection. In addition, if they are not using SG tube inspection methods whose capabilitiesare consistent with the NRC's position, addresseesshould provide an assessment of how tle tube inspectionsperformed at theirplant meet the inspection requirements of the TS in conjunction with CriteriaIX and XI of 10CFR Part50, Appendix B, and corrective action taken in accordancewith Appendix B, CriterionXVI. This assessment should also addresswhether the tube inspection practicesare capable of detectingflaws of any type that may potentially be present along the length of lhe tube requiredto be inspected and that may exceed the applicable tube repaircriteria.
HNP Response:
Steam Generator tube inspections performed at Harris Nuclear Plant (HNP) are consistent with the NRC's position regarding tube inspections.
HNP has three Westinghouse Model Delta 75 steam generators. The tubing material in each of the steam generators is thermally treated Inconel Alloy 690. In addition, the tubes installed in rows 1 through 17 were thermally stress relieved after bending.
The tubes were hydraulically expanded at both ends for the full length of the tubesheet and are supported by a number of stainless steel tube supports (trefoil tube hole design).
In the last inspection, May 2004, HNP performed the following tube inspection scope in Steam Generator C:
- 20%fidl length bobbin inspection
- Rotating Coil inspection of bobbin indicationsfor resolution of anomalous signals.
HNP uses tube inspection methods that are capable of detecting flaw types that potentially may be present. Prior to each inspection, a degradation assessment, which includes operating experience, is performed to identify degradation mechanisms that potentially may be present, and a technique validation assessment is performed to verify that the eddy current techniques are capable of detecting those flaw types identified in the degradation assessment.
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Attachment 1 to SERIAL: HNP-04-133
- 2. If addressees conclude thatfull compliance with the TS in conjunction with Criteria IX, XI and XVI of 10 ,CFR Part50, Appendix B, requires corrective action, they should discuss theirproposed correctiveactions (e.g., changinig inspection practices consistent with the NRC's position or submitting a TS amendment request with the associatedsafety basisfor limiting the inspections) to achievefidl compliance. If addressees choose to change their TS, the staff has included in the Attachment suggested changes to the TS definitionsfor a tube inspection andfor plugging limits to show what may be acceptable to the staff in cases where the tubes are expandedfor thefidl depth of the tube sheet and where the extent of the inspection in the tube sheet region is limited HNP Response:
Steam Generator tube inspections performed at HNP are consistent with the NRC's position regarding tube inspections. Therefore, this question does not apply.
- 3. Forplants where SG tube inspections have not been or are not being performed consistent with the NRC's position on the requirements in the TS in conjunction with CriteriaIX, XI, andXVI of 10 CFR Part50, Appendix B, the licensee should submit a safety assessment (i.e., ajustificationforcontinued operation based on maintaining tube structuraland leakage integrity)that addressesany differences between the licensee's inspection practicesand those calledfor by the NRC's position. Safety assessments should be submittedfor all areas of the tube requiredto be inspected by the TS where flaws have the potential to exist and inspection techniques capable of detecting theseflaws are not being used, and should include the basisfor not employing such inspection techniques. The assessment should include an evaluation of (1) whether the inspectionpractices rely on an acceptancestandard(e.g., cracks located at least a minimum distance ofx below the top of tube sheet, even if these cracks cause complete severance of the tube) which is differentfronm the TS acceptance standards(i.e., the tube plugging limits or repaircriteria),and (2) whether the safety assessment constitutes a change to the "method of evaluation" (as defined in 1OCRF50.59)for establishingthe structuraland leakage integrity of the joint. If the safety assessment constitutes a change to the method of evaluation under 10 C'FR 50.59, the licensee should determine whether a license amendment is necessarypursuant to that regulation.
HNP Response:
Steam Generator tube inspections performed at HNP are consistent with the NRC's position regarding tube inspections. Therefore, this question does not apply.
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Text
? am CJ Progress Energy U.S. Nuclear Regulatory Commission OCT 2 8 2004 Serial: HNP-04-133 ATTENTION: Document Control Desk 10 CFR 50.54(f)
Washington, DC 20555 SHEARON HARRIS NUCLEAR POWER PLANT, UNIT NO. 1 DOCKET NO. 50-400/LICENSE NO. NPF-63 60-DAY RESPONSE TO NRC GENERIC LETTER 2004-01, "REQUIREMENTS FOR STEAM GENERATOR TUBE INSPECTIONS" Ladies and Gentlemen:
On August 30, 2004, the Nuclear Regulatory Commission (NRC) issued Generic Letter (GL) 2004-01, "Requirements for Steam Generator (SG) Tube Inspections," which requested licensees to provide information describing the SG tube inspections performed at their plant during the last inspection. If the SG tube inspection methods are not consistent with the NRC's position on inspection methods, then additional actions are requested. The GL requested this information within 60 days.
Attachment 1 provides the requested 60-day response to GL 2004-01 for the Harris Nuclear Plant (HNP).
Please refer any question regarding this submittal to Mr. Dave Corlett at (919) 362-3137.
I declare, under penalty of perjury, that the attached information is true and correct.
(Executed on OCT 2 8 2004
- Sincerely, Terry C. Morton Manager, Support Services TM/rgh
Attachment:
- 1. 60-Day Response to Generic Letter (GL) 2004-01, "Requirements for Steam Generator Tube Inspections" c:
Mr. R. A. Musser, NRC Senior Resident Inspector Mr. C. P. Patel, NRC Project Manager Dr. W. D. Travers, NRC Regional Administrator Progress Energy Carolinas, Inc.
Harris Nuclear Plant P.O. Box 165 New Hill, NC 27562
Attachment 1 to SERIAL: HNP-04-133 SHEARON HARRIS NUCLEAR POWER PLANT, UNIT NO. 1 DOCKET NO. 50400/LICENSE NO. NPF-63 60-DAY RESPONSE TO GENERIC LETTER (GL) 2004-01, "REQUIREMENTS FOR STEAM GENERATOR TUBE INSPECTIONS" Within 60 days of the date of this generic letter, addressees are requested to provide the following information to the NRC.
- 1. Addressees should provide a description of the SG tube inspectionsperfonned at their plant during the last inspection. In addition, if they are not using SG tube inspection methods whose capabilitiesare consistent with the NRC's position, addresseesshould provide an assessment of how tle tube inspectionsperformed at theirplant meet the inspection requirements of the TS in conjunction with CriteriaIX and XI of 10CFR Part50, Appendix B, and corrective action taken in accordancewith Appendix B, CriterionXVI. This assessment should also addresswhether the tube inspection practicesare capable of detectingflaws of any type that may potentially be present along the length of lhe tube requiredto be inspected and that may exceed the applicable tube repaircriteria.
HNP Response:
Steam Generator tube inspections performed at Harris Nuclear Plant (HNP) are consistent with the NRC's position regarding tube inspections.
HNP has three Westinghouse Model Delta 75 steam generators. The tubing material in each of the steam generators is thermally treated Inconel Alloy 690. In addition, the tubes installed in rows 1 through 17 were thermally stress relieved after bending.
The tubes were hydraulically expanded at both ends for the full length of the tubesheet and are supported by a number of stainless steel tube supports (trefoil tube hole design).
In the last inspection, May 2004, HNP performed the following tube inspection scope in Steam Generator C:
- 20%fidl length bobbin inspection
- Rotating Coil inspection of bobbin indicationsfor resolution of anomalous signals.
HNP uses tube inspection methods that are capable of detecting flaw types that potentially may be present. Prior to each inspection, a degradation assessment, which includes operating experience, is performed to identify degradation mechanisms that potentially may be present, and a technique validation assessment is performed to verify that the eddy current techniques are capable of detecting those flaw types identified in the degradation assessment.
Page Al-I of 2
Attachment 1 to SERIAL: HNP-04-133
- 2. If addressees conclude thatfull compliance with the TS in conjunction with Criteria IX, XI and XVI of 10 ,CFR Part50, Appendix B, requires corrective action, they should discuss theirproposed correctiveactions (e.g., changinig inspection practices consistent with the NRC's position or submitting a TS amendment request with the associatedsafety basisfor limiting the inspections) to achievefidl compliance. If addressees choose to change their TS, the staff has included in the Attachment suggested changes to the TS definitionsfor a tube inspection andfor plugging limits to show what may be acceptable to the staff in cases where the tubes are expandedfor thefidl depth of the tube sheet and where the extent of the inspection in the tube sheet region is limited HNP Response:
Steam Generator tube inspections performed at HNP are consistent with the NRC's position regarding tube inspections. Therefore, this question does not apply.
- 3. Forplants where SG tube inspections have not been or are not being performed consistent with the NRC's position on the requirements in the TS in conjunction with CriteriaIX, XI, andXVI of 10 CFR Part50, Appendix B, the licensee should submit a safety assessment (i.e., ajustificationforcontinued operation based on maintaining tube structuraland leakage integrity)that addressesany differences between the licensee's inspection practicesand those calledfor by the NRC's position. Safety assessments should be submittedfor all areas of the tube requiredto be inspected by the TS where flaws have the potential to exist and inspection techniques capable of detecting theseflaws are not being used, and should include the basisfor not employing such inspection techniques. The assessment should include an evaluation of (1) whether the inspectionpractices rely on an acceptancestandard(e.g., cracks located at least a minimum distance ofx below the top of tube sheet, even if these cracks cause complete severance of the tube) which is differentfronm the TS acceptance standards(i.e., the tube plugging limits or repaircriteria),and (2) whether the safety assessment constitutes a change to the "method of evaluation" (as defined in 1OCRF50.59)for establishingthe structuraland leakage integrity of the joint. If the safety assessment constitutes a change to the method of evaluation under 10 C'FR 50.59, the licensee should determine whether a license amendment is necessarypursuant to that regulation.
HNP Response:
Steam Generator tube inspections performed at HNP are consistent with the NRC's position regarding tube inspections. Therefore, this question does not apply.
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