ML12095A249
| ML12095A249 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek (DPR-016) |
| Issue date: | 04/04/2012 |
| From: | Jesse M Exelon Generation Co, Exelon Nuclear |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| RA-12-043, TAC ME7219 | |
| Download: ML12095A249 (6) | |
Text
10 CFR 50.55a April 4, 2012 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 Oyster Creek Nuclear Generating Station Renewed Facility Operating License No. DPR-16
Subject:
Response to Request for Additional Information - Relief Request to Extend the Fourth Inservice Inspection (lSI) Interval
References:
1)
Letter from M. D.
(Exelon Generation Company, LLC) to U.S. Nuclear Regulatory Commission, "Submittal of Relief Request to Extend the Fourth Inservice Inspection (lSI) Interval," dated September 30,2011 2)
Letter from J. G. Lamb (U.S. Nuclear Regulatory Commission) to M. J. Pacilio ((Exelon Generation Company, LLC), "Oyster Creek Nuclear Generating Station Request for Additional Information Regarding Relief Request to Extend the Fourth Inservice Inspection Interval (TAC No. ME7219)," dated February 6,2012 In the Reference 1 letter, Exelon Generation Company, LLC (Exelon) requested relief (Relief Request R-41) from the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV) Code,Section XI, "Rules for Inservice Inspection of Nuclear Power Plant Components," to extend the Inservice Inspection (lSI) interval by three months. The fourth lSI interval is currently scheduled to end on October 14, 2012. In the Reference 2 letter, the U.S. Nuclear Regulatory Commission requested additional information. Attached is our response to that request.
There are no regulatory commitments in this letter.
Re(~uest for Additional Information ReqUi8st to Fourth Inservice Inspec::;tlC)n (I Interval April 4, 201 2
If you have any qUE~stic)ns Iv\\rv'arnir\\rI this Respectfully,
~J!~~
Michael D. JessV Director - Licensing & Regulatory Affairs Exelon Generation Company, LLC ple,3se contact Tom Loomis at (610) o.
Attachment:
Response to Request for Additional Information - Relief Request R-41 cc:
Regional Administrator, Region I, USNRC USNRC Senior Resident Inspector, OCNGS Senior Project Manager [OCNGS] USNRC
Attachment Response to Request for Additional Information
- Relief Request R*41
1 Number quantity.
Response
following is the current list of components that remain to be examined in the lnspe<:tlcln interval.
10-year Exam Exam I Components Examined Number of Category Item No.
Components Remaining Class 1 B-A B1.12 Vessel Lonqitudinal Welds 12 B-A B1.21 Reactor Vessel Head Circumferential Welds 1
B-A B1.22 Vessel Head Meridional Welds I
8 B-A B1.30 Vessel ShelHo-Flanae Welds 1
B-F B5.10 Reactor Vessel Dissimilar Metal Welds Nozzle-to-Safe End 5
NPS 4" or B-F B5.20 Reactor Vessel Dissimilar Metal Welds Nozzle-to-Safe End 1
Less Than NPS 4" I
I!H
- 1 B6.20 Reactor Vessel Closure Head Studs in Place 32 B-( ]-1 I B6.30 Reactor Vessel Closure Head Studs When Removed 4
I I I ~-( H I B6.40 Vessel Threads in Flanqe 32 B-G-1 I B6.50 Vessel Closure Washer, Bushinqs 64 I
B-J B9.11 Pipino Circumferential Welds NPS 4" or Greater 31 I B-J B9.21 Pipino Circumferential Welds Less Than NPS 4" 2
I I B-J B9.40 Pipinq Socket Welds 11 I
I B-K B10.10 Welded Attachments for Vessels 8
I
\\ B-K B10.20 Welded Attachments for Pipinq 2
B-K B10.40~tachments for Valves 3
I B-M-1 B12.40 ure Retainino Welds in Valve Bodies 1
I B-O B14.10 I Reactor Vessel CRD Housino Welds 3
I Class 2 C-A C1.10 Pressure Vessel Shell Circumferential Welds 1
C-B C2.31 Pressure Vessel Reinforcinq Plate Welds to Nozzle and Vessel 2
i C-C C3.10 Welded Attachments for Vessels 4
I C-C C3.20 Ltavl i!,"',"';> for Pipinq 4
C-C C3.30 e:t(I1I1'='"t;;, for Pumps 3
i C-F-1 C5.11 Stainless Steel Piping. Piping Circumferential Welds ~ 3/8",
6 I
I Nominal Wall Thickness and> 4" NPS.
I C-F-2 C5.51 Carbon Steel Piping. Piping Circumferential Welds ~ 3/8",
16 I
Nominal Wall Thickness and> 4" NPS.
Class 3 D-A DUO Welded Attachments Pressure Vessels 2
D-A 01.20 Welded Attachments Pipinq 2
D-A 01.30 Welded Attachments Pumps 2
Exam Category Exam Item No.
Components Examined Hnc;o(mc;n to for Additional Information n:;',lu<:J;:), R~41 2
Number of Question:
- 2. The ASME Code (IWA-2430(d)(2>> allows the 5 th inspection interval examinations to begin in the same outage that the final 4 th inspection interval examinations are completed. This could be done without relief from the requirements of IWA-2430. Yet Relief Request R-41 states that the interval will begin at the end of the requested 4th interval extension. Provide a projected schedule for the 5 th interval examinations showing when examination periods would begin and end along with projected outage schedules in the examination periods.
Justify why delaying the start of the 5 th interval provides an acceptable level of quality and safety.
Response
The projected schedule for the 5th interval shoWing when examination periods would begin and end, along with projected outage schedules in the examination periods is provided below.
Starting the Interval at the end of the 4 th Interval on 01/15/13 will allow for a clean transition between intervals without adding the potential confusion of mixed interval examination requirements, code editions, planning, and crediting. The modified interval start date will also decrease the likelihood of future changes due to any subsequent shifting of outage schedules.
The proposed revision does not adversely impact the 5 th Interval or change the pattern of outages within the interval or periods. As seen in the chart, 1R25 would be the last outage in the period under either the current or proposed start date, and likewise for 1R29 being the final outage in the interval. Accordingly, the proposed start of the 5th Interval will not modify the outage examination schedules and thus will maintain an acceptable level of quality and safety.
HA<:;n()n~iA to Request for Additional Information Relief Request R-41 3
Interval Start Date to End Date 01/15/1310 01/14/23*
Period Start Date to End Date 1
01/15/13to 01/14/16 01/15/16 to 01/14/20 3"j 01/15/20to 01/14/23 Outa es Projected Outa Start Date Scheduled 10/14 Scheduled 10/16 Scheduled 10/18 Scheduled 10/20 Scheduled 10/22 lR25 lR26 1R27 1R28 lR29
- Although inspection periods for an entire fifth interval are shown, Oyster Creek operations are planned to cease by the end of 2019 as previously announced.