ML051090300
| ML051090300 | |
| Person / Time | |
|---|---|
| Site: | Salem  (DPR-075) |
| Issue date: | 04/08/2005 |
| From: | Perino C Public Service Enterprise Group |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| TAC MB6091, TAC MB6092 | |
| Download: ML051090300 (6) | |
Text
PSEG Nuclear LLC P.O. Box 236, Hancocks Bridge, New Jersey 08038-0236 APR - 8 2005 LR-N05-01 67 97A PSul-AruclearI,I-C United States Nuclear Regulatory Commission Document Control Desk Washington, DC 20555-001 INSERVICE INSPECTION PROGRAM RELIEF REQUEST S2-13-RR-A06 SALEM GENERATING STATION UNIT 2 FACILITY OPERATING LICENSE DPR-75 DOCKET NOS. 50-311 Pursuant to 10 CFR 50.55a(a)(3)(i), PSEG Nuclear LLC (PSEG) requests the use of American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code) Case N-566-2, Corrective Action for Leakage at Bolted Connections, Section Xl, Division 1, for the Salem Generating Station Unit 2. PSEG proposes to implement the alternative requirements of ASME Code Case N-566-2 when leakage occurs at bolted connections (other than gaseous systems).
The attachment to this letter includes the proposed alternative and supporting justification for the relief. Based on the evaluation contained in the attachment, PSEG has concluded that the proposed alternative provides an acceptable level of quality and safety. Accordingly, this proposal satisfies the requirements of 10 CFR 50.55a(a)(3)(i).
This relief request is applicable to Salem Generating Station Unit 2. PSEG requests approval by the end of April 2005 in order to support Salem Generating Station Unit 2 refueling outage 2R1 4 which commenced on April 6, 2005. Similar relief was granted for Salem Generating Station Unit 1 third 10-year interval, and Unit 2 second 10-year interval (NRC letter dated November 27, 2002, TAC NOS. MB6091 and MB6092).
Should you have any questions regarding this request, please contact Mr. Michael Mosier at 856-339-5434.
Christina L. Perino Director - Regulatory Assurance
Attachment:
ISI Relief Request S2-13-RR-A06 95-2168 REV. 7/99
Document Control Desk APR - 8 2005 LR-N05-0167 C
Mr. S. Collins, Administrator - Region I U. S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 U. S. Nuclear Regulatory Commission ATTN: Mr. D. Collins, Licensing Project Manager - Hope Creek/Salem Mail Stop 08C2 Washington, DC 20555-0001 USNRC Senior Resident Inspector-Salem (X24)
Mr. K. Tosch, Manager IV Bureau of Nuclear Engineering PO Box 415 Trenton, New Jersey 08625
Document Control Desk Attachment I LR-N05-0167 Relief Request S2-13-RR-A06 Use of ASME Code Case N-566-2 Proposed Alternative In Accordance with 10 CFR 50.55a(a)(i)
-- Alternative Provides Acceptable Level of Quality and Safety --
ASME Code Component(s) Affected ASME Section Xl, Class 1, 2, and 3 bolted connections.
Applicable Code Edition and Addenda
1998 Edition, including 2000 Addenda
Applicable Code Requirement
Sub-paragraph IWA-5250(a)(2) of the 1998 Edition, with 2000 Addenda of Section Xl requires removal of all the bolting, performance of VT-3 visual examination of all bolting, and performance of an evaluation in accordance with IWA-31 00 when leakage occurs at bolted connections.
Proposed Alternative PSEG Nuclear, LLC (PSEG) requests the use of ASME Code Case N-566-2, titled
'Corrective Action for Leakage Identified at Bolted Connections, Section Xl, Division 1' in lieu of the requirements of sub-paragraph IWA-5250(a)(2).
PSEG proposes performing an evaluation in accordance with the alternative requirements of ASME Code Case N-566-2 in the event that leakage is found at Class 1, 2, or 3 bolted connections. These alternative requirements specify that, if leakage is detected at a bolted connection, one of the following requirements shall be met:
a) The leakage shall be stopped, and the bolting and component material shall be evaluated for joint integrity as described in (c) below.
b) If the leakage is not stopped, the licensee shall evaluate the structural integrity and consequences of continuing operation, and the effect on the system operability of continued leakage. This engineering evaluation shall include the considerations listed in (c) below.
c) The evaluation of (a) and (b) above is to determine the susceptibility of the bolting to corrosion and failure. This evaluation shall include the following:
- 1. the number and service age of the bolts;
- 2. bolt and component material;
- 3. corrosiveness of process fluid; Document Control Desk LR-N05-0167 Relief Request S2-13-RR-A06 Use of ASME Code Case N-566-2 Proposed Alternative In Accordance with 10 CFR 50.55a(a)(3)(i)
-- Alternative Provides Acceptable Level of Quality and Safety --
- 4. leakage location and system function;
- 5. leakage history at the connection or other system components;
- 6. visual evidence of corrosion at the assembled connection.
In the event that the evaluation of ASME Code Case N-566-2 paragraphs (a) or (b) determines that the relevant condition can be accepted for continuing service, PSEG would periodically conduct visual inspections of affected components (in accordance with PSEG's ASME Section Xl Repair Program requirements) to verify operating conditions have not changed affecting earlier calculation assumptions.
In the event that the relevant condition cannot be accepted for continuing operation using ASME Code Case N-566-2 paragraphs (a) or (b), Salem Generating Station Unit 2 would correct the condition in accordance with its ASME Xl Article IWA-4000 Repair/Replacement Activities and the PSEG ASME Section Xl Repair Program Requirements.
Basis of Alternative for Providing Acceptable Level of Quality and Safety Pursuant to 10 CFR 50.55a(a)(3)(i), relief is requested on the basis that the proposed alternative provides an acceptable level of quality and safety.
Removal of bolts for VT-3 visual examination is not always the most prudent action when leakage is discovered at a bolted connection. Leakage at bolted connections is typically identified during system leakage tests. For Class 1 systems, this leakage test is conducted prior to plant startup following each refueling outage. This test is performed at full operating pressure (2235 psig) and temperature. When leakage is discovered during this test, the corrective action (i.e. removal of bolts) must be performed with the system at full temperature and pressure, or the plant must be cooled down. The removal of a bolt at full temperature and pressure conditions can be extremely physically demanding due to the adverse heat environment. Cooling down the plant subjects the plant to additional heatup and cooldown cycles, and can add 3-4 days to the duration of an outage. Bolted connections associated with pumps and valves are typically studs threaded into the body of the component. Removal of these studs is typically very difficult, requiring expenditure of both time and dose resources due to the length of time that they have been installed and are often damaged during the removal process. This difficulty is compounded when the removal must be performed under heat stress conditions.
The requirements of IWA-5250(a)(2) must be applied regardless of the significance of the leakage or the corrosion resistance of the materials used in the bolted connection.
Implementation of ASME Code Case N-566-2 requires factors such as the number and service age of the bolts, the bolting materials, the corrosiveness of the system fluid, the Document Control Desk Attachment I LR-N05-01167 Relief Request S2-13-RR-A06 Use of ASME Code Case N-566-2 Proposed Alternative In Accordance with 10 CFR 50.55a(a)(3)(i)
-- Alternative Provides Acceptable Level of Quality and Safety --
leakage location and system function, leakage history at the connection or at other system components, and visual evidence of corrosion at the bolted connection be used to evaluate the need for corrective measures.
As previously stated, in the event that the evaluation of ASME Code Case N-566-2 paragraphs (a) or (b) determines that the relevant condition can be accepted for continuing service, PSEG would periodically conduct visual inspections of affected components (in accordance with PSEG's ASME Section XI Repair Program requirements) to verify operating conditions have not changed, affecting earlier calculation assumptions.
In the event that the relevant condition:
- 1. cannot be accepted for continuing operation using ASME Code Case N-566-2 paragraphs (a) or (b), or
- 2. if the component's operating conditions changed, such that an additional calculation (using the newly acquired information) determines that the relevant condition cannot be accepted for continuing operation, or
- 3. PSEG elects to correct the condition, the condition would be corrected in accordance with its ASME Section XI Article IWA-4000 Repair/Replacement Activities and PSEG's ASME Section XI Repair Program requirements.
If the equipment that is leaking can be isolated, the equipment will be isolated and ASME Code Case N-566-2 will not be invoked. If the leakage cannot be isolated and the system affected causes entry into a Technical Specification (TS) Action Statement, ASME Code Case N-566-2 would be invoked and a work plan would be developed for removal and inspection of one bolt at a time. At any time in this process if it is determined that structural integrity cannot be shown to exist, the appropriate actions will be taken in accordance with the Salem Generating Station Unit 2 TS.
Duration of Proposed Alternative This Request, upon approval, will be applicable for the third 10-year interval at Salem Generating Station Unit 2; which commence on November 23, 2003. The use of the ASME Code Case N-566-2 is requested until the NRC publishes the ASME Code Case in a future revision of the applicable Regulatory Guide.
Precedents By letter dated July 8, 2002, PSEG submitted twelve relief requests to the NRC for approval, including relief request SC-RR-A06. On October 10, 2002, supplemental information was provided. The NRC approved use of ASME Code Case N-566-2 for the Document Control Desk Attachment I LR-N05-01 67 Relief Request S2-13-RR-A06 Use of ASME Code Case N-566-2 Proposed Alternative In Accordance with 10 CFR 50.55a(a)(3)(i)
-- Alternative Provides Acceptable Level of Quality and Safety --
duration of the second 1 0-year interval (NRC letter dated November 27, 2002, TAC No.
MB6092). This was determined to be an acceptable alternative to the requirements found within Paragraph IWA-5250(a)(2) of the 1986 Edition (without Addenda) of Section Xl.