ML20115D608
| ML20115D608 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 10/13/1992 |
| From: | Parker T NORTHERN STATES POWER CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9210210050 | |
| Download: ML20115D608 (2) | |
Text
y...
1 h
Northem States Powar Company 414 Nicollra Mall Minneapoks, Minnesots SM01-1927 Telephone (t12) 330-5600 October 13, 1992 10 CFR Part 50 Section 50.55a'g)
U S Nuclear Regulatory Commission Attn:
Document Control Desk Washington, DC 20555 PRAIRIE ISLAND NUCLEAR GENERATING PIANT Docket Nos. 50-282 License Nos. DPR-42 50-306 DPR 60 ASME Code Section XI Inspection and Testing Program Recuest for a Schedule Extension for Longitudinal Weld Irspections W are wrJ ting this irter to request a schedule extension for certain longitudinal weld examinations until our dual unit outage scheduled to begin October 24, 1992.
ASME Section XI requires nondestructive examinc. tion of a portion of longitudinal seam welds when the intersecting circumferentini weld is examined. We reported in J.icensee Event Report 1-92-11 (dated October-13, 1992) that we had failed to examine some longitudinal welds within the required time limits. That report discusses the causes and the corrective acticas to prevtut future omission of weld examinations.
A summary of.the.
omitted examinations is listed below:
Unit 1:
Mein Steam System 8 welds
-RilR System 16 welds
~ Safety Injection System 6 welds Unie 2:
Main Steam Systen 7 welds RilR" System 17 welds Safety " Injection System 11 welds Total number of welds for both units 65 welds
.,. :Xs ~
- 19006h g
' b ik 1210210050 921013
+
FDR ADOCK 05000282 P
3:
Mo E*"#
--USNdQ October 13, 1992 Page.2 of 2 An engineering evaluation was performed to study the safety cf continued operation until t),e examinstions could be completed. This evaluetion concluded that there was little or no risk to safe operatien until the fall outages. The conclusion was based on' the following:
1.
Examination results overall had detected no evidence of any piping-degradation.
2.
The subject piping experiences relatively mild operating conditions.
These operating conditions together with the absence of severe operating transients led to the conclusion that no piping degradation was to be expected.
3.
Longitudinal seam piping has a long history of sati factory operation in operating conditions such as anose at Prairie Island (e.g.,
outside the creep regime).
Based on ths' conclusion thac continued operation is safe, we request that schedular relief be granted for.these wold exami.tations until the dual unit outage schedulod to begin Octohet 24, 1992, during which all missed examinations will be_ completed.
Please contact us if you have any questions related to this request,
,)h po t
/ s' f
w s g w p,rker-
, Thomas h Pa Manager Nuclear Support Services c: Regional Administrator - Region III. NRC Senior ".esident Inspector, NRC
- NRR Project Manager, NRC State of Minnesota Hartford Insurance.
-J E Silberg-l i
x
-