ML102950566
| ML102950566 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 04/23/2010 |
| From: | NRC Region 1 |
| To: | NRC Region 1 |
| References | |
| FOIA/PA-2010-0334 | |
| Download: ML102950566 (5) | |
Text
OSutside of Scope}
BRANCH 3 DAILY 423/o10 STATUS Highlighted items were discussed at DRP/DRS Coordination meeting Jutsid BOLD items are new Outside of Scope Wekend Coverage: Dan iALI (9X)j>007 AL2=(2of3)0.1.>
.,. AL*3-(iX)>071 3,
Outside of Scope AFW Piping Degradation
Background:
i Unit1 - PSEG identified significant piping and coating degradation for the buried AFW supply piping for 2 of the 4 B 7
steam generators. The pipe was schedule 80, 4" inside diameter, carbon steel piping with a protective coating. Based E
on preliminary UT measurements of the piping, engineering determined AFW system operability could not be assured through next operating cycle. Additional UT examinations were performed to evaluate the structural integrity of the pipe and to identify the sections of pipethat needed replacement. Based on these measurements, PSEG will replace all deep and shallow pipe on both the 12 and 14 headers. Following replacement of about 80 ft of shallow piping.,
Z PSEG removed the supports for the piping that was not replaced and identified a section under a pipe support clamp that was well below minimum wall (.077). Subsequent Utsidetermined that the thickness measurement was the result of a localized pit. To fully evaluate the impact of the identif'id pipe degradation on the AFWsystemPSEG hired I3 of Qsb~
teAWyfmS ied
Structural Integrity Associates, Inc to complete a finite element analysis.
Extent of Condition:
Unit 2 has greater margin - it is a newer plant and is presumably in better condition; documentation exists that proves the piping was opened and inspected -16 years ago and found to be in pristine condition; ISI code gives more allowance to an operating unit (they can take credit for up to 90% of the yield stress). DRS reviewed photographs and has no immediate safety concerns. There were no similar inspections of Unit 1 AFW piping.
Unit 2 - PSEG determined that they did not perform ASME code required pressure drop test for the buried sections of the 22 and 24 headers. Unit 2 entered a 24-hr shutdown action statement at 1132 on 4/21 for this condition. PSEG subsequently completed a risk analysis that determined that it is ok to extend the periodicity of the surveillance for 7 days.
NRC Next Steps:
0 Conform the PSEG risk assessment to delay AFW testing is reasonable - Cahill 9
Confirm the finite element analysis for the unit 1 as found condition is acceptable including the use of appropriate methods and assumptions - Conte/O'Hara/HQ a
Confirm the technical evaluation that supports 1275 psig is bounding (including a faulted S/G scenario) - Hansell/Silk Evaluate the Unit 2 AFW extent of condition operability assessment (focus on the differences between Unit I & 2) -
Schroeder/O'Hara Follow-up on the control air coating concern at the support clamp - O'Hara/Gray Evaluate ongoing AFW piping replacements on Unit 1 - O'Hara Evaluate repairs to the control air system on Unit 1 - O'Hara Information Needs - discussed during 4/19, 1315, status call - answers highlighted Design records for as installed piping on Unit 1 & 2 (not found as of yet, still looking)
Unit 1 AFW past operability assessment Unit 1 AFW as found condition finite element analysis Unit 2 AFW operability determination J~.
lUEt* UI bo~rpe
Outside of Scope Additional Items Status Board Items:
t aS*1SmIANb*t i6d piping (PIQRI TY) -
waitibg on* PSEG FEA and operability determinationto enter MC 0309
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