L-HU-04-027, Nuclear Management Co., LLC, 10 CFR 50.55a Request GR-04-01; Request for Authorization to Utilize Code Case N-661,Alternative Requirements for Wall Thickness Restoration of Classes 2 and 3 Carbon Steel Piping for Raw Water Service Sectio
| ML042100484 | |
| Person / Time | |
|---|---|
| Site: | Monticello, Palisades, Kewaunee, Point Beach, Prairie Island, Duane Arnold  |
| Issue date: | 07/28/2004 |
| From: | Weinkam E Nuclear Management Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| L-HU-04-027 | |
| Download: ML042100484 (6) | |
Text
Nuclear Management Company, LLC July 28, 2004 L-HU-04-027 10 CFR 50.55a(a)(3)(i)
U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 Duane Arnold Energy Center Palisades Nuclear Plant Docket 50-331 Docket 50-255 License No. DPR-49 License No. DPR-20 Kewaunee Nuclear Power Plant Point Beach Nuclear Plant Units 1 and 2 Docket 50-305 Dockets 50-266 and 50-301 License No. DPR-43 License Nos. DPR-24 and DPR-27 Monticello Nuclear Generating Plant Prairie Island Nuclear Generating Plant Docket 50-263 Units 1 and 2 License No. DPR-22 Dockets 50-282 and 50-306 License Nos. DPR-42 and DPR-60 10 CFR 50.55a Request GR-04-01; Request For Authorization To Utilize Code Case N-661 Pursuant to 10 CFR 50.55a(a)(3)(i), Nuclear Management Company, LLC (NMC) hereby requests Nuclear Regulatory Commission (NRC) authorization of the enclosed relief request for the Inservice Inspection Program of the NMC licensees identified in this letter.
Authorization is requested to use the alternative requirements of Code Case N-661, Alternative Requirements for Wall Thickness Restoration of Classes 2 and 3 Carbon Steel Piping for Raw Water Service, in lieu of certain American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code,Section XI, IWA-4000 requirements. Additional restrictions to be implemented in addition to those specified in the Code Case N-661 as part of the proposed alternative are discussed in the enclosure.
Use of the proposed alternative will provide an acceptable level of quality and safety, as described in the enclosed request.
NMC requests authorization by July 23, 2005. NMC will use Code Case N-661 under the approved relief only until such time as the code case is published in a future version of Regulatory Guide 1.147, Inservice Inspection Code Case Acceptability, ASME Section XI, Division 1.
700 First Street
- Hudson, Wisconsin 54016 Telephone: 715-377-3700
Document Control Desk Page 2 This letter makes no new commitments or changes to any existing commitments.
Edward J. Weinkam Director of Regulatory Services Nuclear Management Company, LLC Enclosures (2) cc:
Administrator, Region III, USNRC Project Managers, Duane Arnold, Kewaunee, Monticello, Palisades, Point Beach, Prairie Island, USNRC Senior Resident Inspectors, Duane Arnold, Kewaunee, Monticello, Palisades, Point Beach, Prairie Island, USNRC State Consultation (Minnesota Department of Commerce, Ms. Ave M. Bie -
Public Service Commission of Wisconsin)
ENCLOSURE 1 REQUEST FOR AUTHORIZATION TO UTILIZE CODE CASE N-661 10 CFR 50.55a Request GR-04-01 Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i)
- 1.
ASME Code Component(s) Affected ASME Section XI, Class 2 and 3 Carbon Steel Piping for Raw Water Service
- 2.
Applicable ASME Section XI Code Edition and Addenda The applicable Codes for Repair/Replacement activities are as follows:
Monticello (2001 Edition)
Prairie Island (1998 Edition with the 2000 Addenda)
Point Beach (1998 Edition with the 2000 Addenda)
Kewaunee (1998 Edition with the 2000 Addenda)
Palisades (1989 Edition)
Duane Arnold (1992 Edition with the 1992 Addenda)
- 3.
Applicable Code Requirement
ASME Section XI 1989 Edition IWA-4120(a) requires that repairs be performed in accordance with the Owners Design Specification and the original Construction Code of the component or system.
IWA-4310 requires that defects be removed or reduced in size in accordance with IWA-4000.
ASME Section XI 1992 Edition with the 1992 Addenda IWA-4170(b) requires that repairs and installation of replacement items shall be performed in accordance with the Owners Design Specification and the original Construction Code of the component or system.
IWA-4310 requires that defects be removed or reduced in size in accordance with IWA-4000.
ASME Section XI 1998 Edition with the 2000 Addenda IWA-4221(a) requires that items used for repair/replacement activities shall meet the applicable Owners Requirements.
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ENCLOSURE 1 IWA-4221(b) requires that an item to be used for repair/replacement activities shall meet the Construction Code specified in accordance with (1), (2) or (3) below.
(1) When replacing an existing item, the new item shall meet the Construction Code to which the original item was constructed.
(2) When adding a new item to an existing system, the Owner shall specify a Construction Code that is no earlier than the earliest Construction Code used for construction of any originally installed item in that system.
(3) When adding a new system, the Owner shall specify a Construction Code that is no earlier than the earliest Construction Code used for other systems that perform a similar function.
IWA-4422.1(a) states that a defect is considered removed when it has been reduced to an acceptable size.
ASME Section XI 2001 Edition IWA-4221(a) requires that items used for repair/replacement activities shall meet the applicable Owners Requirements.
IWA-4221(b) requires that an item to be used for repair/replacement activities shall meet the Construction Code specified in accordance with (1), (2) or (3) below.
(1) When replacing an existing item, the new item shall meet the Construction Code to which the original item was constructed.
(2) When adding a new item to an existing system, the Owner shall specify a Construction Code that is no earlier than the earliest Construction Code used for construction of any originally installed item in that system.
(3) When adding a new system, the Owner shall specify a Construction Code that is no earlier than the earliest Construction Code used for other systems that perform a similar function.
IWA-4422.1(a) states that a defect is considered removed when it has been reduced to an acceptable size.
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Reason for Request
Relief is requested from replacement or weld repair of wall thinning conditions in Class 2 and 3 carbon steel raw water piping systems to the design specification and the original construction code. Such thinning may be the result of various degradation mechanisms such as erosion, corrosion, cavitation and pitting. The use of Code Case N-661 will provide adequate time so that pipe replacement can be planned to reduce impact on system availability including Maintenance Rule applicability and availability of replacement materials.
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ENCLOSURE 1
- 5.
Proposed Alternative and Basis for Use NMC proposes to implement the requirements of ASME Code Case N-661 as an alternative under 10 CFR 50.55a(a)(3)(i) for Class 2 and 3 raw water piping systems resulting from degradation mechanisms such as erosion, corrosion, cavitation, or pitting as an alternative to the requirements of the ASME Section XI code as referenced above. These types of defects are typically identified by small leaks in the piping system or by pre-emptive non-code required examinations performed to monitor the degradation mechanisms. The alternative repair technique described in Code Case N-661 involves the application of additional weld metal on the exterior of the piping system that restores the wall thickness requirement. This repair technique is utilized whenever engineering evaluation determines that such a repair is suitable for the particular defect or degradation being resolved. Provisions for use of this Code Case will be addressed in the Repair/Replacement Program for each site.
Provisions for implementation of this Code Case will be addressed on a plant specific basis in each sites Repair/Replacement Program. The provisions will require that adjacent areas be examined to verify that the repair will encompass the entire flawed area and that no other unacceptable degraded locations exist within a representative area. This will be dependent on the degradation mechanism present. An evaluation of the degradation will be performed to determine the re-examination schedule to be conducted over the life of the repair.
The repair will be considered to have a maximum service life of two fuel cycles unless the re-examinations conducted during each of the two fuel cycles establish the expected life of the repair.
Additionally, the following restrictions will be placed on the use of Code Case N-661 to ensure that the use of the Code Case will provide an acceptable alternative pursuant to 10 CFR 50.55a(a)(3)(i):
(a) if the root cause of the degradation has not been determined, the repair is only acceptable for one cycle, (b) weld overlay repair of an area can only be performed once in the same location, and (c) when through-wall repairs are made by welding on surfaces that are wet or exposed to water, the weld overlay repair is only acceptable until the next refueling outage.
The basis for use of the repair technique described in Code Case N-661 is that the ASME Code subcommittee for Section XI determined that this repair technique provides an acceptable alternative to the requirements of IWA-4000 and provides an acceptable level of quality and safety. Therefore, the proposed alternative is justified per 10 CFR 50.55a(a)(3)(i).
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ENCLOSURE 1 Code Case N-661 was approved by the ASME Section XI Code Committee on July 23, 2002; however, it has not been incorporated into NRC Regulatory Guide 1.147 Inservice Inspection Code Case Acceptability, ASME Section XI Division 1.
Therefore NMC requests use of the alternative repair technique described via this relief request. A copy of the ASME Section XI Code Case N-661 is provided as for reference.
- 6.
Duration of Proposed Alternative NMC requests authorization of Code Case N-661 to be used for each plants 10-year ISI interval (see table below) or until the NRC publishes Code Case N-661 in a future revision of Regulatory Guide 1.147. Upon incorporation into the Regulatory Guide, NMC will review and follow the conditions specified. All other ASME Code,Section XI requirements for which relief was not specifically requested and authorized by the NRC staff will remain applicable including third party review by the Authorized Nuclear Inservice Inspector.
Plant ISI Interval Interval Dates Monticello Nuclear Generating Plant 50-263 Fourth 05/01/03 - 05/31/12 Prairie Island Nuclear Generating Plant, Units 1 and 2, 50-282 & 50-306 Fourth 12/21/04 - 12/20/14 Point Beach Nuclear Plant, Units 1 and 2, 50-266 and 50-301 Fourth 07/01/02 - 06/30/12 Kewaunee Nuclear Power Plant 50-305 Fourth 06/16/04 - 06/16/14 Palisades Nuclear Plant 50-255 Third 05/12/95 - 12/12/06 Duane Arnold Energy Center 50-331 Third 11/01/96 - 11/01/05
- 7.
Precedents NMC has determined that the following previous Authorizations to use Code Case N-661 are directly applicable to this Relief Request:
(1) Letter from NRC to Southern Nuclear Company, Edwin I. Hatch Nuclear Plant, Units 1 and 2, Joseph M. Farley Nuclear Power Plant, Units 1 and 2, and Vogtle Electric Generating Plant, Units 1 and 2 (TAC Nos. MB8959, MB8960, MB8961, MB8962, MB8963, and MB8964), dated November 21, 2003, ADAMS Accession No. ML033280037.
(2) Letter from NRC to TXU Energy, Comanche Peak Steam Electric Station, Units 1 and 2 - RE: Relief from the Requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code Section XI, Concerning Relief Requests C-2 and C-7 (TAC Nos. MB7947 and MB7948),
dated February 18, 2004, ADAMS Accession No. ML040490624.
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