ML043630370
| ML043630370 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 12/21/2004 |
| From: | Rosalyn Jones Duke Energy Corp |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| TAC M88484, TAC M88485, TAC M88486 | |
| Download: ML043630370 (7) | |
Text
mdDuke r0 Power.
A Duke Energy Company RON A. JONES Vice President Oconee Nuclear Site Duke Power ONOl VP / 7800 Rochester Highway Seneca, SC 29672 864 885 3158 864 885 3564 fax December 21, 2004 U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555
Subject:
Duke Energy Oconee Nuclear Station, Units 1, 2 and 3 Docket Nos. 50-269,-270,-287 Fourth Ten Year Inservice Inspection Interval Requests for Relief No. 04-ON-015 Pursuant to 10 CFR 50.55a(g)(5)(iii), attached is a Request for Relief from certain requirements of ASME Boiler and Pressure Vessel Code Section XI, 1998 Edition through the 2000 Addenda.
The specific inspections referenced in the attached request for relief have been determined to be impractical.
Further, these inspections were addressed by a previous relief request (ONS-009, submitted May 12, 1994) which was approved by the staff (SER dated November 15, 1995, reference TAC Numbers M88484, M88486, M88486).
The prior relief expired at the end of the third ten year interval.
There has been no change in design, geometry, or inspection methodology which would justify a change in the determination that these inspections are impractical.
Therefore, Duke Energy requests that the NRC grant relief as authorized under 10 CFR 50.55a(g)(6)(i).
If there are any questions or further information is needed you may contact R. P. Todd at (864) 885-3418.
Very r y yours, R.
ones Site Vice President
,AD(- -
Attachment www. dukepower. corn
4-U. S. Nuclear Regulatory Commission December 21, 2004 Page 2 xc w/att: Mr. William D. Travers Administrator, Region II U.S. Nuclear Regulatory Commission Atlanta Federal Center 61 Forsyth St., SWW, Suite 23T85 Atlanta, GA 30303 L. N. Olshan, Project Manager, Section 1 Project Directorate II Division of Licensing Project Management Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, DC 20555-0001 xc(w/o attch):
M. C. Shannon Senior NRC Resident Inspector Oconee Nuclear Station Mr. Henry Porter Division of Radioactive Waste Management Bureau of Land and Waste Management SC Dept. of Health & Environmental Control 2600 Bull St.
Columbia, SC 29201
Z-Duke Energy Corporation Oconee Nuclear Station Units 1, 2, and 3 FOURTH 10-YEAR INTERVAL REQUEST FOR RELIEF NO. 04-ON-015 Duke Energy Corporation has determined that conformance with certain ASME Section Xl Code requirements is impractical. Therefore, pursuant to 10CFR50.55a(g)(5)(iii), Duke Energy Corporation requests relief from applicable portions of the code.
This request addresses items for Code Table IWB-2500-1 Examination Category B-D, Full Penetration Welded Nozzles in Vessels.
System/Component(s) for Which Relief is Requested:
High Pressure Injection System Letdown Cooler Nozzle Inside Radius Section Oconee Unit 1 ID Number 1-51 A-1 8792-1 -V-2 1-51 A-1 8792-1 -V-6 1-51 A-1 -53755-V1 1-51 A-1 -53755-V2 Item Number B03.160.001 B03.160.002 B03.160.003 B03.160.004 Oconee Unit 2 ID Number 2-LDCA-IN-V1 2-LDCA-OUT-V2 2-LDCB-IN-V1 2-LDCB-OUT-V2 Oconee Unit 3 Item Number B03.160.001 B03.160.002 B03.160.003 B03.160.004 ID Number 3-LDCA-IN-V2 3-LDCA-OUT-V5 3-LDCB-IN-V1 3-LDCB-OUT-V2 Item Number B03.160.001 B03.160.002 B03.160.003 B03.160.004 Page 1 of 4
P.A II.
Applicable Code Edition and Addenda
The Oconee Units 1, 2, and 3 Fourth Interval Inservice Inspection Plans are written to the requirements of the 1998 Edition of ASME Section Xl through the 2000 addenda.
Ill.
Code Requirement from Which Relief is Requested:
Table IWB-2500-1, Category B-D, Item B3.160, Volumetric Examination of inside radius sections on heat exchanger nozzle to shell welds.
IV. & V. Impracticality/Burden Caused by Compliance:
Due to the size and geometry of the nozzle inside radius on the Letdown Coolers, we have been unable to perform a meaningful (i.e.
unable to get sound into the area of interest) volumetric examination.
The weld joint geometry, which is essentially a branch connection arrangement using a set-on nozzle, where the nozzle thickness prevents access to the examination volume. In order to scan all of the required volume, the Letdown Cooler nozzles would have to be redesigned to allow scanning of the inner radius, which is impractical.
See Attachment A for a drawing of the Letdown Coolers.
(The drawing in Attachment "A" is for the Unit 2 "B" Letdown Cooler but the configuration for the nozzle inside radius sections is the same for all 3 Units)
VI.
Proposed Alternate Examination:
None proposed or planned.
VII.
Duration of Proposed Alternative Schedule:
This request will be applicable at Oconee Nuclear Station during the refueling outages for the fourth ten-year inservice inspection interval as shown in the tables below:
I Oconeel Item No.
RFO B03.160.001 23 B03.160.002 23 B03.160.003 25 B03.160.004 25 Oconee 2 Item No.
REQ B03.160.001 21 B03.160.002 21 B03.160.003 26 B03.160.004 26 Page 2 of 4
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.k Oconee 3 Item No.
RFO B03.160.001 24 B03.160.002 24 B03.160.003 27 B03.160.004 27 VIII.
Precedents On May 12,1994 Relief Request ONS-009 was filed for examinations required during the third interval for these same item numbers. Relief was granted by SER dated November 15,1995.
(Tac Numbers # M88484, M88485 and M88486)
IX.
Justification for Granting Request for Relief:
The ultrasonic examination of the weld volume adjacent the inside radius section, as required by ASME Section Xl, Table IWB-2500-1, Examination Category B-D, Item Number 803.150 is a more critical location and will provide adequate assurance of the integrity of the welded connection.
Duke Energy will use code required pressure testing and VT-2 visual examination to ensure component integrity. The Code requires (reference Table IWB-2500-1, Examination Category B-P, All pressure Retaining Components (Item Number B15.40 Heat Exchangers) that a system leakage test be performed after each refueling outage for Class 1 components. These tests require a VT-2 visual examination for evidence of leakage. This testing will provide reasonable assurance of weld/component integrity.
In addition to the above Code required examinations (volumetric and pressure test), there are other activities which provide a high level of confidence that, in the unlikely event that leakage did occur through these inside radius sections, it would be detected and isolated. Specifically, leakage from these inside radius sections would be detected by monitoring of the Reactor Coolant System (RCS) inventory, which is performed once each shift under unit specific procedure PT/1,2, or 3/A/0600/1 0, "RCS Leakage". This RCS leakage monitoring is a requirement of Technical Specification 3.4.13, "Reactor Coolant System Leakage". Any leakage is also evaluated in accordance with this Technical Specification. The leakage could also be detected through several other methods. One is the Reactor Building air particulate monitor. This monitor is sensitive to low leak rates; the iodine monitor, gaseous monitor and area monitor are capable of detecting any fission products in the coolant and make these monitors sensitive to coolant leakage. A second is the Page 3 of 4
level indicator in the Reactor Building normal sump. A third is a loss of level in the Letdown Storage Tank.
Based on the required volumetric examinations, VT-2 test, and other activities previously listed, it is Duke's belief that this provides a reasonable assurance of component integrity. Thus, an acceptable level of quality and safety will have been achieved and will not endanger public health and safety.
Sponsored By:
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