ML041050384
| ML041050384 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 04/07/2004 |
| From: | Byrne S South Carolina Electric & Gas Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| RR3-V-1 | |
| Download: ML041050384 (3) | |
Text
Stephen A. Byrne Senior Vice President, Nuclear Operations 803.345.4622 A SCANA COMPANY April 7, 2004 Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555
Dear Sir / Madam:
Subject:
VIRGIL C. SUMMER NUCLEAR STATION (VCSNS)
DOCKET NO. 50/395 OPERATING LICENSE NO. NPF-12 REQUEST TO USE ALTERNATIVES TO ASME CODE REQUIREMENTS IN VCSNS THIRD INSERVICE INSPECTION INTERVAL (RR3-V-1)
South Carolina Electric & Gas Company (SCE&G) hereby submits the attached request for using an alternative to the examination requirements of the ASME Code.
SCE&G has determined that the proposed alternative will provide an acceptable level of quality and safety.
A detailed description of the proposed alternative, including basis for relief, is included as an attachment to this letter. SCE&G requests NRC review and approval of this request by November 1, 2004, so that appropriate changes to the VCSNS Examination Program can be completed prior to VCSNS refuel outage 15 currently scheduled for April 15, 2005.
SCE&G is submitting the attached relief request in accordance with 1 OCFR50.55a(f)(6)(i).
Should you have any questions, please call Mr. Ronald B. Clary at (803) 345-4757.
VeryJqujy yours, JT/SAB/dr Attachment c:
N. 0. Lorick N. S. Cards T. G. Eppink (w/o Attachment)
R. J. White L. A. Reyes K. R. Cotton K. M. Sutton F n AA. 8 * 'I-D. G. Dobson S. C. Smith NRC Resident Inspector NSRC RTS (C-04-0745)
File (810.19-2)
DMS (RC-04-0063)
I I
' Owl SCE&G I Virgil C.
Summer Nudear Station
- P. 0. Box 88
- Jenkinsville, Soulh Corolino 29065.T (803] 345.5209. wwwscana.com
Document Control Desk Attachment C-04-0745 RC-04-0063 Page 1 of 2 South Carolina Electric & Gas Co. (SCE&G)
Virgil C. Summer Nuclear Station (VCSNS)
Relief Request RR3-V-1
Subject:
Bi-directional Testing of Service Water (SW) Return Check Valves Components:
Category C SW System Valves XVC03130A XVC03130B Code Requirement:
ASME OM Code, 1998 Edition with Addenda through 2000 requires that necessary valve obturator movement during exercise testing be demonstrated by performing both an open and a closed test [ISTC-5221 (a)].
Relief Request:
SCE&G requests relief from the check valve bi-directional exercise testing requirements specified in ISTC-5221 (a).
Alternate Test:
VCSNS proposes to continue performing full stroke exercise testing to the safety related open position during refueling outages without performing bi-directional exercise testing to the non-safety related closed position.
Basis for Relief:
Pursuant to 10 CFR 50.55a(f)(6)(i), relief is being requested on the basis that compliance with the specified requirements is impractical.
These normally open SW system discharge check valves perform an active safety function in the open position to allow SW return flow to the service water pond.
Unimpaired return flow is required for the SW system to provide maximum cooling of essential heat loads during accident conditions.
Document Control Desk Attachment C-04-0745 RC-04-0063 Page 2 of 2 The valves perform no safety function in the closed position. The design close function of these check valves is to prevent siphoning of the pond in the event of a postulated crack of a large diameter pipe in the SW system piping and to prevent inadvertant flooding during SW system maintenance from an incorrect valve lineup.
SW piping is moderate energy piping.
Therefore, the design rules require that cracks, not breaks, must be postulated. Calculations for the postulated crack project a leak flow range less than the capacities of the sump pumps in the affected areas.
Due to the relatively small size of the resulting crack, the existing plant can easily handle a leak without requiring the valves to shut. Therefore, the back-seat function has been determined to be a non-active function by SCE&G, since the SW system, Diesel Generator Building, and Intermediate Building are designed to accommodate all postulated cracks.
The majority of the SW return piping is underground including the SW system discharge check valves. The system configuration does not provide a means to employ non-intrusive test methods or disassembly to confirm valve closure. The valves are buried without direct access, making these alternate techniques impractical.
Based on the absence of a safety function in the closed position, elimination of back seat testing for these valves has no safety impact.
Implementation Schedule:
This relief will be implemented during the third IST interval at VCSNS.
Implementation period will be from April 1, 2004 to December 31, 2013.