RS-06-182, Proposed Alternative to Performance of System Pressure Tests and VT-2 Visual Examination Requirements for All Class 2 Instrument Air (IA) Piping and the Class 3 IA Piping Supplying All SRVs and Both Feedwater Containment Outboard
| ML063620098 | |
| Person / Time | |
|---|---|
| Site: | Clinton  |
| Issue date: | 12/15/2006 |
| From: | Benyak D AmerGen Energy Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| RS-06-182 | |
| Download: ML063620098 (12) | |
Text
AmerGen.
AmerGen Energy Company, LLC www.exeloncorp.com An Exelon Company 4 300 Winfield Road Warrenville, I L 60555 10 CFR 50.55a RS-06-182 December 15, 2006 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Clinton Power Station, Unit 1 Facility Operating License No. NPF-62 NRC Docket No. 50-461
Subject:
Proposed Alternative to Performance of System Pressure Tests and VT-2 Visual Examination Requirements for all Class 2 Instrument Air (IA) Piping and the Class 3 IA Piping Supplying all SRVs and Both Feedwater Containment Outboard Isolation Check Valves In accordance with 10 CFR 50.55a, "Codes and standards," paragraph (a)(3)(i), AmerGen Energy Company, LLC (AmerGen), hereby requests NRC approval of the following request for a proposed alternative to the requirements of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code, Section Xl, "Rules for Inservice Inspection of Nuclear Power Plant Components," 1989 Edition, no addenda, paragraphs IWC-2500 and IWD-2500 for the remainder of the second ten-year interval of the Inservice Inspection Program for Clinton Power Station (CPS) which ends December 31, 2010.
ASME Section XI, paragraphs IWC-2500 and IWD-2500, state that components shall be examined and pressure tested as specified in Tables IWC-2500-1 and IWD-2500-1. Tables IWC-2500-1 and IWD-2500-1 require performance of VT-2 visual examinations during system pressure tests. As an alternative to the examination requirements of Table IWC-2500-1 and IWD-2500-1, CPS is proposing to perform pressure decay testing on the Class 2 and 3 Instrument Air piping supplying all 16 Safety Relief Valves (SRVs) and both Feedwater containment outboard isolation check valves as required in the surveillance procedures. The proposed alternative testing will provide an equivalent level of quality and safety.
AmerGen requests approval of this request by December 31, 2007.
There are no regulatory commitments contained in this letter.
A47
December 15, 2006 U. S. Nuclear Regulatory Commission Page 2 Should you have any questions concerning this letter, please contact Mr. Timothy A. Byam at (630) 657-2804.
Respectfully, Darin M. Benyak Manager - Licensing Attachments: (1)
(2)
(3) 10 CFR 50.55a Request Number 4212 Piping & Instrumentation Diagrams (For Information Only)
Acceptance Criteria From Procedure CPS 9061.11 (For Information Only)
ATTACHMENT 1 CLINTON POWER STATION 10 CFR 50.55a Request Number 4212 Proposed Alternate in Accordance with 10 CFR 50.55a(a)(3)(i)
Alternative Provides Acceptable Level of Quality and Safety
- 1. ASME Code Components Affected Class 2 Instrument Air (IA) piping and components between containment isolation valves 1 IA01 2A/B and 1 IA01 3A/B and check valves 1 IA042A/B. This includes the following lines, valves and components shown on Clinton Power Station (CPS)
Piping and Instrumentation Diagram (P&ID) M05-1040 sheet 7 not listed above.
" Lines 11A71BA/BB-1, 1IA14GA/GB-1, 1IA95A/B-1, 1IA93AA/BA-3/4 and 1 IA96AA/BA-3/4.
Valves 1IA131A/B, 11A129A/B and the blind flanges on lines 1IA95A/B-1.
Class 3 IA system piping and components requiring inspection. This includes the following IA lines and valves supplying all 16 safety relief valves (SRVs) and both Feedwater containment outboard isolation check valves.
P&ID M05-1040 sheet 7 lines - 1IA79CA/CB-1, 1IA92AA/BA-3/4, 1IA102BA-1/2, 1IA103BA-1/2, 1IA71AA/AB-1, 11A87A/B-1/2, 1IA125A/B-1/2, 11A122A/B-1, 1 1A88A/B-1/2, 1 IA71 CA/CB-1, 1 IA71 DA/EA/FA/GA-1/2 and 1 IA71 DB/EB/FB/GB/FC-1/2.
P&ID M05-1040 sheet 7 valves - 1 1A075A/B, 1 IA076A/B, 1 IA1 30A/B, 1IA1170A/B, 0IA18MA/B, 1IA044A/B, 1IA1171 A/B, 11A1172A/B, 11A096C/D and 1 1A097A/B. NOTE - Strainers 1 IA26FA/FB are not Code components.
P&ID M10-9002 sheet 1 lines - 1IA71DA/DB/EA/EB/FA/FB/FC-1/2, 1 IA85A/B/C/D/E/F/G-1/2, 1 MS71CE/DE-1/2, 1MS72AE/BE-1/2, 1MS73BE/CE-1/2, 1 MS74CE-1/2, 1 MS71 CG/DG-3/4, 1 MS72AG/BG-3/4, 1 MS73BG/CG-3/4, 1MS74CG-3/4, 1 MS71CH/DH-1/2, 1MS72AH/BH-1/2, 1MS73BH/CH-1/2, 1 MS74CH-1/2, 1 MS71CF/DF-3/4, 1 MS72AF/BF-3/4, 1 MS73BF/CF-3/4, 1 MS74CF-3/4, 1 MS71 CC/DC-2, 1 MS72AC/BC-2, 1 MS73BC/CC-2, 1 MS74CC-2, 1 MS71 CJ/CK/DJ/DK-1 1/4, 1 MS72AJ/AK/BJ/BK-1 1/4, 1 MS73BJ/BK/CJ/CK-1 1/4 and 1 MS74CJ/CK-1 1/4.
P&ID M10-9002 sheet 1 valves - 1 1A094A/B/C/D/E/F/G, 1 B21 -
F039B/C/D/E/H/K/S, 1 B21 -F331 C/D, 1 B21 -F332A/B, 1 B21 -F333B/C, 1 B21 -
F334, valves 'G' on M1 0-9002-sheetl and 1 B21 -F082B/C/D/E/H/K/S.
P&ID M1 0-9002 sheet 1 accumulators - 1 B21 -A003B/C/D/E/H/K/S.
P&ID M1 0-9002 sheet 2 lines - 1 IA71GA/GB-1/2, 1 1A86C/E-1/2, 1 MS75AE/BE-1/2, 1 MS76CE/DE-1/2, 1MS77AE/CE/DE-1/2, 1MS78BE/CE-1/2, 1MS75AC/BC-2, 1 MS76CC/DC-2, 1MS77AC/CC/DC-2, 1MS78BC/CC-2, 1MS75AG/AH/BG/BH-1 1/4,1 MS76CG/CH/DG/DH-1 1/4, 1 MS77AG/AH/CG/CH/DG/DH-1 1/4 and 1 MS78BG/BH/CG/CH-1 1/4.
P&ID M1 0-9002 sheet 2 valves - 1 1A095C/E, 1 B21 -F036 A/F/G/J/L/M/N/P/R and 1 B21 -F081 A/F/G/J/L/M/N/P/R.
P&ID M1 0-9002 sheet 2 accumulators - 1 B21 -A004A/F/G/J/L/M/N/P/R.
Page 1 of 4
ATTACHMENT 1 P&ID M10-9004 sheet 8 lines - 1FW26BA/BB - 1/2, 1FW27BA/BB-1/2, 1 FW26CA/CB-2 and 1 FW28AA/AB-3/4.
P&ID M1 0-9004 sheet 8 valves - 1 B21 -F433A/B and 1 B21 -F492A/B.
P&ID M10-9004 sheet 8 accumulators - 11B21-A300A/B.
2. Applicable Code Edition and Addenda
American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code, Section Xl, "Rules for Inservice Inspection of Nuclear Power Plant Components," 1989 Edition, no addenda, paragraphs IWC-2500 and IWD-2500.
3. Applicable Code Requirement
ASME Section Xl, paragraphs IWC-2500 and IWD-2500, state that components shall be examined and pressure tested as specified in Tables IWC-2500-1 and IWD-2500-
- 1. Tables IWC-2500-1 and IWD-2500-1 require performance of VT-2 visual examinations during system pressure tests.
Examination Categories: Class 2 - C-H, All Pressure Retaining Components.
Class 3 - D-A, Systems in Support of Reactor Shutdown Function.
Item Numbers:
Class 2 - C7.30, Piping and Pressure Retaining Components and C7.70, Valves and Pressure Retaining Components.
Class 3 - D1.10, Pressure Retaining Components
4. Reason for Request
Relief is requested from the performance of system pressure tests and VT-2 visual examination requirements specified in Tables IWC-2500-1 and IWD-2500-1 for all Class 2 IA piping and the Class 3 IA piping supplying all SRVs and both Feedwater containment outboard isolation check valves.
5. Proposed Alternative and Basis for Use
As an alternative to the examination requirements of Tables IWC-2500-1 and IWD-2500-1, CPS will perform pressure decay testing on the Class 2 and 3 IA piping supplying all 16 SRVs and both Feedwater containment outboard isolation check valves as required in surveillance procedure CPS 9061.11, "Instrument Air Check Valve Operability and Pipe Pressure Test."
Pursuant to 10 CFR 50.55a(a)(3)(i), relief is requested on the basis that the proposed alternative testing method provides an acceptable level of quality and safety.
Page 2 of 4
ATTACHMENT 1 Surveillance procedure CPS 9061.11, verifies the operability of SRV actuation capability and check valves in the IA supply lines to all 16 SRVs and both Feedwater containment outboard isolation check valves. This surveillance test is performed for each individual SRV and both Feedwater containment outboard isolation check valves as a requirement of the CPS Inservice Testing (IST) program. One specific test this surveillance performs, is a pressure decay test of the SRV and Feedwater containment outboard isolation check valve accumulators, as well as associated piping and valves. The pressure decay test is performed by isolating and pressurizing these accumulators and associated piping to the nominal operating pressure. The decay in pressure is then monitored through calibrated pressure measuring instrumentation. If any pressure decay acceptance criterion (see ) is exceeded, the surveillance identifies appropriate troubleshooting steps to perform, including soap-bubble application to locate leakage.
The pressure decay test performed as part of CPS 9061.11 identifies any degradation of the Class 2 and 3 ADS supply piping and the SRV and Feedwater containment outboard isolation check valve accumulators and associated piping.
The volume tested by this surveillance encompasses all piping and components requiring testing under ASME Section XI for these portions of the IA system. This surveillance is performed on a greater frequency than that required in Tables IWC-2500-1 or IWD-2500-1 and the test pressure is consistent with the pressure requirements of both tables. Thus, the testing performed during this surveillance will provide the same level of quality and safety as the pressure testing and VT-2 visual examination requirements of Tables IWC-2500-1 and IWD-2500-1.
The VT-2 visual examination described in Tables IWC-2500-1 and IWD-2500-1 and performed once per inspection period, would not provide an increase in safety, system reliability, or structural integrity. In addition, performance of a VT-2 visual examination would require applying a leak detection solution to a large amount of piping and components, many of which are in elevated dose rate areas with limited access. VT-2 inspections would result in additional radiation exposure (estimated 2 Rem) and industrial safety challenges without any added benefit in the level of quality and safety. These inspections would not be consistent with As Low As Reasonably Achievable (ALARA) practices.
Relief is requested from the performance of system pressure tests and VT-2 visual examination requirements specified in Tables IWC-2500-1 and IWD-2500-1 for the Class 2 and 3 IA system piping and components identified in this request on the basis that an existing CPS surveillance provides an acceptable level of quality and safety.
6. Duration of Proposed Alternative
Relief is requested for the remainder of the second ten-year interval of the Inservice Inspection Program for CPS, Unit 1 which ends December 31, 2010.
7. Precedents
Page 3 of 4
ATTACHMENT 1 A similar request was made by Exelon Generation Company, LLC for the LaSalle County Station (Reference 1) and subsequently approved by the NRC (Reference 2).
- 8. References
- 1. Letter from Mr. C. G. Pardee (Exelon Generation Company, LLC) to the U. S.
NRC, "LaSalle County Station Relief Requests PR-08 and PR-10, Alternates to the Examination Requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section Xl, "Rules for Inservice Inspection of Nuclear Power Plant Components," 1989 Edition, Table IWC-2500-1," dated December 21, 2001
- 2. Letter from U. S. NRC to Mr. J. L. Skolds (Exelon Generation Company, LLC),
"LaSalle County Station, Units 1 and 2 - Relief Requests PR-08 and PR-10 (TAC Nos. MB3780 and MB3781)," dated June 28, 2002
- 3. American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV) Code,Section XI, "Rules for Inservice Inspection of Nuclear Power Plant Components," 1989 Edition, No Addenda, Subsection Tables IWC-2500-1 and IWD-2500-1 Page 4 of 4
ATTACHMENT 2 Piping & Instrumentation Diagrams:
(For Information Only)
M05-1040, Sheet 7 M1 0-9002, sheets 1 and 2 M10-9004, sheet 8
ATTACHMENT 3 Acceptance Criteria From Procedure CPS 9061.11 (For Information Only)
Accum uiaior Headers for all SRVs except 1B21-F051C and D
< 1.5 psig
> 108 minutes Accumulator Headers for 1B21-F051C and D
< 1.5 psig
> 31 minutes Smaller volume than other SRVs Accumulator Header for Feedwater Check Valve
< 1.5 psig
> 26 minutes Smaller volume than SRVs ADS Supply Header to Accumulator This inspection tests over 200 feet of piping Headers
<22 psig
> 60 minutes and components.