NG-08-0557, Response to Request for Additional Information Regarding Revised Request to Allow Use of the Provisions of IWA-4132 for Remainder of the Fourth Ten-Year Inservice Inspection Interval
| ML082180449 | |
| Person / Time | |
|---|---|
| Site: | Duane Arnold  |
| Issue date: | 07/25/2008 |
| From: | Richard Anderson Duane Arnold |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NG-08-0557 | |
| Download: ML082180449 (8) | |
Text
FPL Energy Duane Arnold, LLC 3277 DAEC Road 0 Palo, Iowa 52324 FPL Energy.
Duane Arnold Energy Center July 25, 2008 NG-08-0557 10 CFR 50.55a(a)(3)(i)
U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Duane Arnold Energy Center Docket No: 50-331 Op. License No: DPR-49 Response to Request for Additional Information Regarding Revised Request to Allow Use of the Provisions Of IWA-4132 for Remainder of the Fourth Ten-Year Inservice Inspection Interval
Reference:
c, rlU Icj,-.o i Letter, Richard L. Anderson (FPL Energy Duane Arnold) to 0 i,-DocumrentGontrblcDesl K(UJ$NRC.); ."Request toAIlIowUse of the Provisionsfl WA4*;*forf)Remainder~ofutheeFou.l Ten-Year Inservice Inspection Interval," dated February 28, 2008,
,..L. ": :. r G-08-",01373.* ('ML0Q 07,t1;0427).,:e,
- 2. Letter*, Rich,ýird.Li._n rs§nqi('PL7pEnefgy)yDuane'Arnold) to
,Document.ControltDeskp(USN -,)i,,.Revised Request to Allow
. ,:.!,Use of *the, Provisions of IWA-41 32 for Remainder of the Fourth
".n-eDa-r1nseryice-Inspection Interval," dated March 28, 2008, NG-08-0201 (ML080990626)
- 3. Letter, Karl D. Feintuch (USCRC) to Richard L. Anderson (FPL Energy Duane Arnold), "Request for Additional Information Pertaining to Revised Request NDE-R009 to Allow Use of Provisions of IWA-4132 for Remainder of Fourth 10-Year Inservice Inspection Interval," dated July 11, 2008 (ML081910030)
On February 28, 2008,.:FR*P.Energy,,D~uane Arnold, LLC (hereafter, FPL Energy Duane Arnold) submitted the-relief request of Refere~npc 1. In phone calls dated March 13, 2008 and March17, th.eNC p!rp.id e.0q1mments-.concerning t2h08e; Reference 1. Subsequently qn'Marph2U,,2,008,,pRPPL Epnergy Du~anel Arnold submitted Reference 2w, wbich .supeTsedJed',Refere.nce 1.
In Reference 3, the Staff issueda..,reqppsutEFer. qdJ[tioI~l imformatiorn<regarding 1 Reference 2. The responseJaeh o4INequest-;of ferepgrtn .jstprovided ,ijvthe,'-.'
enclosure to thisletter.Girfni c,-'
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NG-08-0557 July 25, 2008 Page 2 of 2 FPL Energy Duane Arnold requests approval of this request by February 28, 2009.
The conditions of the "B" Recirculation Pump Mechanical Seal continue to be monitored. FPL Energy Duane Arnold plans to maintain communication with the NRC regarding the condition of the "B" Recirculation Pump Mechanical Seal and the need for this, relief.
This letter contains no new commitments nor revises any previous commitments.
If you have any questions or require additional information, please contact Steve Catron at (319) 851-7234.
ýRichard L. Ande r n Vice President, Duane Arnold Energy Center FPL Energy Duane Arnold, LLC Enclosure cc: Administrator, Region Ill, USNRC Project Manager, DAEC, USNRC Resident Inspector, DAEC, USNRC
Enclosure to NG-08-0557 Page 1 of 6 ENCLOSURE Response to Request for Additional Information Regarding the Request to Allow Use of the Provisions of IWA-4132 for the Remainder of the Fourth Ten-Year Inservice Inspection Interval
Enclosure to NG-08-0557 Page 2 of 6 ENCLOSURE Response to Request for Additional Information Regarding the Request to Allow Use of the Provisions Of IWA-4132 for the Remainder of the Fourth Ten-Year Inservice Inspection Interval NRC Question #1:
- 1. On page 5 of Relief Request NDE-R009, Item 5 requires that
"...Preservice and inservice inspections (ISI) will be completed (i.e., visual VT-1 of the bolting)..."
(a) confirm whether the visual VT-1 of the bolting will be performed per IWA-2211 of the American Society of Mechanical Engineers Code,Section XI, which defines VT-1 as detection of discontinuities and imperfections on the surface of components (bolts in this case) including such conditions as cracks, wear, corrosion, or erosion.
FPL Energy Duane Arnold Response:
The VT-1 examination conducted is planned to be performed per IWA-2211 as required by Table IWB-2500-1, Category B-G-2, Item No. B7.60.
NRC Question #2:
(b) because VT-1 examination does not look for leakage, discuss when or how potential leakage from the reactor coolant pump (RCP) seal flange assembly will be detected during preservice and inservice inspections.
FPL Energy Duane Arnold Response:
If the Reactor Recirculation Pump seal flange assembly is installed during a refueling outage, the Class 1 pressure test, which is required following Reactor Pressure Vessel disassembly associated with refueling, would be used to detect potential leakage even though not required. If the Reactor Recirculation Pump seal flange assembly is installed during an outage other than a refueling outage the potential for leakage would be detected during the normal leakage walkdown performed when reactor pressure is approximately 400 psig during the startup sequence.
Enclosure
- -, to NG-08-0557 Page 3 of 6 NRC Question #3:
(c) discuss why volumetric or surface examinations are not required (or are not mentioned) to be conducted on the parts of the RCP seal flange assembly.
FPL Energy Duane Arnold Response:
The relief would only be used if the pressure boundary of the Reactor Recirculation Pump seal flange assembly has not received a repair/replacement. Since there will have been no repair/replacement performed on the pressure boundary when the relief is used, there is no requirement for a volumetric or surface examination. Additionally, an inservice or preservice volumetric or surface examination on this component would not be required when no repair work has been performed.
NRC Question #4:
(d) discuss the frequency of the inservice inspections.
FPL Energy Duane Arnold Response:
The frequency of the inservice inspection of the seal assembly bolting is based on IWB-2500-1, Category B-G-2, Item No. B7.60 which states in footnote 2 "For vessels, pumps, or valves, examination of bolting is required only whenthe component is examined under Examination Category B-B, B-L-2, or B-M-2. Examination of bolted connection is required only once during the interval." The Examination Category B-L-2 is the appropriate category for pumps and the frequency of examination is required only when the pump is disassembled for maintenance, repair, or volumetric examination.
NRC Question #5:
- 2. On page 5 of Relief Request NDE-R009, Item 8 requires that "...Testing of the seal flange assembly will be completed as needed to determine acceptability..."
(a) clarify what testing is intended or implied in Item 8 and whether this is preservice and/or inservice testing.
FPL Energy Duane Arnold Response:
The discussed testing is anticipated to be the Post-Maintenance Testing of the Reactor Recirculation Pump seal flange assembly to verify no leaks. That
Enclosure to NG-08-0557 Page 4 of 6 Post-Maintenance Testing is normally a walk-down when the reactor pressure is approximately 400 psig.
NRC Question #6:
(b) discuss why the testing will be performed on an "as-needed" basis. The staff believes that testing should be performed whenever the RCP seal flange assembly is replaced to show the structural integrity of the replacement component.
FPL Energy Duane Arnold Response:
A Post-Maintenance Test would be performed each time a Reactor Recirculation Pump seal flange assembly is rotated from stock and installed.
The Post-Maintenance Test will verify leak tightness. Since the Reactor Recirculation Pump seal flange assembly was previously installed, structural integrity is not in question.
NRC Question #7:
- 3. On page 5, second paragraph, of Relief Request NDE-R009, the licensee stated that "...If there is a repair/replacement activity performed on the item to be installed, FPL Duane Arnold plans to follow IWA-4000, including the use of an Inspector, NIS-2 form and pressure testing ..."
(a) item 1 (on page 4) states that the seal flange assembly being installed will be a like-for-like "replacement." This implies that the stock rotation is a repair/replacement activity and not preventive maintenance activity.
However, on pages 3, 4, and 5, the licensee states that the subject stock rotation is of preventive maintenance. Clarify whether the RCP seal flange rotation is a replacement activity or preventive maintenance activity.
FPL Energy Duane Arnold Response:
The rotation of the Reactor Recirculation Pump seal flange assembly is a preventative maintenance activity unless the asterisk to item 7 on page 5 of Reference 1 applies. The asterisked statement would only apply if an ASME Section XI repair/replacement activity is performed in addition to rotation of the seal flange assembly.
Enclosure to NG-08-0557 Page 5 of 6 NRC Question #8:
(b) it seems that the licensee does not intend to perform pressure testing for the subject stock rotation because it considers the subject stock rotation as a preventive maintenance activity. In absence of pressure testing,
.discuss how the installed RCP seal flange assembly can be shown to be operable without leakage regardless whether the subject stock rotation activity is preventive maintenance or repair/replacement activity.
FPL Energy Duane Arnold Response:
One of the criteria for the use of this relief is that the stock rotation will have been previously installed (Item 4 on page 5 of Reference 1). The work performed on the stock Reactor Recirculation Pump seal flange assembly would not include any work on the pressure boundary portion of the assembly. The seal flange assembly after installation would be verified to have no leakage during the walkdown when the reactor pressure is approximately 400 psig.
NRC Question #9:
(c) Explain why pressure testing (i.e. system leakage testing) is not needed.
FPL Energy Duane Arnold Response:
As stated in Reference 1, the Recirculation Pump Seal Flange Assembly consists of the seal cartridge and the seal flange. The seal flange is a pressure boundary component that supports the seal cartridge. The entire assembly (seal flange and seal cartridge) is bolted to the pump casing.
During maintenance on the seal cartridge the complete assembly (seal cartridge and flange) is rotated as a single unit.
Reference 1 also states that the normal activity of testing components under the criteria of IWA-4132 involves their removal from their installed location by mechanical means (i.e., disassembly and re-assembly of mechanical joints);
this activity constitutes the basis for IWA-4132. IWA-4132 recognizes that, rather than re-install the same component tested, a similar component from stock can be rotated into service in its place. FPL Energy Duane Arnold believes the criteria established in IWA-4132 for stock rotation of snubbers and pressure relief valves for testing can also be applied to the stock rotation of Recirculation Pump seal flange assemblies for preventative maintenance.
The intent of the relief request is to use the alternative requirements of IWA-4132 for the preventative maintenance activity on the Reactor Recirculation
Enclosure to NG-08-0557 Page 6 of 6 Pump seal flange assembly. These alternative requirements include specific criteria that must be met. One of these criteria is that the item being rotated from stock had been previously installed. This means that a new Reactor Recirculation Pump seal flange assembly can not be installed under these alternative requirements. The Reactor Recirculation Pump seal flange assembly rotated would have already received a System Leakage Test when it was new. Since there is also a requirement in IWA-4132 that no repair/replacement activity has been performed (which would be performed on the pressure boundary) there is no need to perform the system leakage test. The walkdown when the reactor pressure is at approximately 400 psig verifies the installation of the flange with the associated gasket is leak tight.
NRC Question #10:
- 4. Provide the end date for the fourth ten-year ISI inspection interval at Duane Arnold.
FPL Energy Duane Arnold Response:
The fourth ten-year ISI inspection interval at the Duane Arnold Energy Center ends on February 21, 2014.
Reference:
- 1. Letter, Richard L. Anderson (FPL Energy Duane Arnold) to Document Control Desk (USNRC), "Revised Request to Allow Use of the Provisions of IWA-4132 for Remainder of the Fourth Ten-Year Inservice Inspection Interval," dated March 28, 2008, NG-08-0201 (ML080990626)