ML20069F965
| ML20069F965 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 06/03/1994 |
| From: | Hunger G PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9406090170 | |
| Download: ML20069F965 (5) | |
Text
.
=
. =.
Station Support Department 10CFR50.55a i
s
{
PEc0 Energy Company f4udear Group Headquarters 965 Chesterbrook Boulevard Wayne, PA 19087-5691 June 3,1994 Docket Nos. 50-277 50-278 License Nos. DPR44 DPR-56 f
i U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555
Subject:
Peach Bottom Atomic Power Station, Units 2 and 3 Request for Relief from implied 30 Day implementation l
of ASME Section XI Repairs (Relief Request No. RR-19)
Dear Sir:
Attached for your review and approval is Relief Request No. RR-19 for the Peach Bottom Atomic 1
Power Station (PBAPS), Units 2 and 3, Second Ten-Year Interval inservice Inspection (ISI)
Program. PECO Energy Company is requesting relief for the implementation of repairs to Class
[
3 pressure retaining components in the Emergency Service Water System.
i 1
i While there is no prescribed schedule for implementation of Class 3 repairs or replacements, PECO Energy's position is that the implied timely implementation of Class 3 repairs or replacements should be within 30 days. Accordingly, PECO Energy Company requests a one-time schedular relief from this implied 30 day implementation schedule in order to develop and perform corrective actions while avoiding a dual unit shutdown.
i If you have any questions or require additional information, please do not hesitate to contact us.
i i
.Very truly yours,
[,
1, G. A. Hunger. Jr., Director Licensing
(
Attachment cc:
T. T. Martin, Administrator, USNRC, Region l W. L Schmidt, USNRC Senior Resident inspector, PBAPS i
.l i
f i
l 9406090170 940603 DR ADOCK 05000277 hri l!
PDR k
l l
i m.
I l
j I
l i
I I
(
1 i
l i
i.
t t
i L
I l
i i
ATTACHMENT i
I Peach Bottom Power Station Units 2 and 3 i.
Inservice inspection Program l
RELIEF REQUEST No. RR-19 I
I t
il I
h
+
,.m,.
1 i
Specification M-733, Rev.
PBAPS 2 & 3 i
ISI Program Appendix A-19 Page 1 of 3 REI.IEF REQUEST NO. RR-19 Revision 0 I.
IDENTIFICATION OF COMPONENTS ISI Class 3 pressure retaining components in the Emergency Service Water (ESW) System /
Emergency Cooling Water (ECW) System.
The ESW System is designed to provide a reliable supply of cooling water to the emergency diesel generator engine coolers and selected equipment coolers and compartment air coolers during a loss of off-site power.
The ECW System is designed to provide an adequate on-site heat sink to be used in conjunction with liigh Pressure Service Water (11PSW) to support the Residual licat Removal (RllR) System during reactor shutdown, and with ESW to provide cooling for the reactor building cooling water heat exchangers, emergency diesel generator coolers, and the Emergency Core Cooling System (ECCS) pump room coolers during a loss of the Conowingo Pond or during a design basis flood.
The ECW System also provides sufficient water storage to allow operation of the emergency cooling tower for seven days, without makeup.
The specific location of the subject components, within the referenced systems, is annotated on the attached schematic diagram of the ECW System. This portion of the system is a ASME Class 3, moderate energy (i.e. less than 200* F max. operating temperature, and less than 275 psig max. operating pressure) cooling water system, and does not normally operate.
11.
CODE REOUIREMENTS FROM W111CII RELIEF IS REOUESTED ASME Section XI,1980 Edition through and including the Winter 1981 Addenda, Subsections IWA-4000, IWD-4000, IWA-7000, and IWD-7000 provide rules for the repair and replacement of pressure retaining components within the ASME Class 3 jurisdictional boundaries of the Section XI Code. While there is no prescribed schedule for implementation of Class 3 repairs or replacements, PECO Energy's position is that the implied timely implementation of identified ASME Section XI Repairs or Replacements should be 30 calendar days. Accordingly, PECO Energy Company requests one-time schedular relief from the implied 30 day implementation schedule in order to develop and perform corrective actions, while avoiding a dual unit shutdown.
Ill.
BASIS FOR REl.lEF As documented in Nonconformance Report (NCR) PB 93-00809, a leaking pinhole indication was discovered in the ESW Booster Pump suction piping during plant operations. The structural integrity of the degraded piping was verified by computation, and therefore the operability of the system was confirmed. The NCR disposition was to perform a non-intrusive ASME Section XI welded Code repair to correct the situation. During preparation for the Code repair, additional areas of concern were identified. A more comprehensive examination was performed of the indication, and five (5) additional areas (welds) were also examined. The structural integrity of the updated situation was again evaluated and found acceptable, thereby reaffirming the operability of the component and system. The effects of the leakage on surrounding components and cooling capabilities of the system were also evaluated and found to be acceptable, A revision i
Specification M-733, Rev.
PBAPS 2 & 3 ISI Program Appendix A-19 Page 2 of 3 Relief Request RR-19 (Cont'd) to the original NCR was then developed. The revised NCR disposition included intrusion into the system to perform both welded repairs, as well as potential replacement of pressure boundary components.
The above circumstances were communicated to the NRC during a conference call on April 28, 1994. The need for this relief request was discussed during the teleconference. It was determined that the relief request was not needed at that time, since a Code repair was planned for the immediate future.
Since the degraded component is located in a non-isolable portion of the system, common to both Unit 2 and Unit 3, special isolation techniques are required to implement the repairs, otherwise, a dual unit shutdown would be necessary. Repeated attempts to isolate the affected portion of the system, using freeze plugs, have been unsuccessful, thereby delaying implementation of the planned repairs beyond the time frame identified in the teleconference. Therefore, this relief request is being submitted.
Also, because of the isolation problems described above, deferral of a Code acceptable repair until the next refueling outage, in accordance with the guidance of Generic Letter 9045, is not applicable; since a one unit refueling outage does not allow this portion of the system to be isolated.
While Code acceptable repair and replacement are still under consideration, PECO Energy is investigating other options, including an alternative repair.
IV.
ALTERNATE PROVISIONS As a result of finding the pinhole leak in the pipe weld, ultrasonic (UT) thickness measurements were performed at the as-found indication as well as other locations around the weld.
Subsequently, additional UT thickness measurements were performed to check fo:: wall thinning or corrosion at other locations in this portion of the ESW System. The results of these additional examinations were then used to reaffirm both structural integrity, as well as component / system operability. While the pinhole has stopped leaking, it continues to be visually monitored on a weekly basis. Additionally, follow-up NDE will be performed every 90 days to verify the condition of the degradation, until repairs can be performed. Expansion of the existing examination locations for raw water piping, developed in accordance with Generic Letter 89-13, will be assessed.
PECO Energy will keep the NRC Staff informed as to progress of Code repairs or any alternative repair techniques being considered for implementation. Verbal notification of which option will be pursued is expected on or before July 15, 1994. It is intended that this relief will apply until either a Code acceptable repair is implemented, or until an alternative repair plan is submitted to, and approved by the NRC.
Specification M-733, Rev.
PBAPS 2 & 3 ISI Program Appendix A-19 Page 3 of 3 Relief Request RR-19 (Cont'd)
Figure RR-19.1 I
,e MPtNE' WW il
~
,ww I
I es. 9
[
~
h,>w
- = = -
lj g_
~
l'O~ bw
~4 a
l l llT ll 1
1 L. e.y
-r c yyx -.
ll l
@' Q.,
h M 2 It-( l.
ll l q r
b:
4 l
d[q::,..., h
- I=I--,-
d71 e-3 v-tre a_
ll a
I_
s ly@ @_m %) Jf V-g 4
... m y
y d==
J '
""-' ' - " ^ ~ -
+
l gg n
pq I
T
~ _ _ 'simMimer I
8 I
w i
AREA 0F INTEREST t
i EXCERPT FROM W-330 SHT.1 T
i