ML102950457

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Branch 3 Daily Status
ML102950457
Person / Time
Site: Salem  PSEG icon.png
Issue date: 04/20/2010
From:
NRC Region 1
To:
References
FOIA/PA-2010-0334
Download: ML102950457 (5)


Text

Outside of Scope -1 I

BRANCH3 DAILY 4120110 STATUS Highlighted items were discussed at DRPIDRS Coordination rmeting MIr%'l *na ,rn n.u4 Outside of Scope 9-0.

I: SALEM ONE ;.j Weekend Coverage:

Outside of Scope ALI 9X)?0.07 AL27(2of3)4> 11 AL3(iXŽO.13 4

AFW Piping Degqradation

Background:

il

  • PSEG identified significant piping and coating degradation for the buried AFW supply piping for 2 of the 4 steam generators. The pipe was schedule 80, 4" inside diameter, carbon steel piping with a protective coating. Based 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 pipe that needed replacement. Based on these measurements, PSEG'twiiireplrace all deerd~ihi 0'e on boftlhe1ifii2nd14 heaýdeirs's. Following replacement of about 80 ft of shallow pi in I

>2 I

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 UTs determeind that the thickness measurement was the result of a localized pit. To fully evaluate the impact of the identified pipe degradation on the AFW system PSEG hired 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 foundto be in pristine condition; ISI code gives more allowance to an operating unit (they can take credit for upt6o90% of the yield stress). DRS reviewed photographs and has no immediate safety concerns. There were no similar inspections of Unit I AFW piping.

" On each unit there are three safety-related systems with buried piping (ASW, SW and control air) o Control air coating in tact, PSEG will document the inspection.

o Control air small leak. PSEG cut out and replaced. Will evaluate the failure mechanism (believe it was repeatedly stepped on).

o No previous UT inspections for service water piping, previously focused on seals for bell and spigot joints (as of end of outage all will have been replaced), Based on SW piping OE the current concern would be groundwater corrosion of the metal bands between concrete layers.

Questions and Concerns:

  • Design change to support 1275 psig (may not perform analysis since all piping to be replaced)
  • Unit 2 EOC (operability based on differences between Unit 1 &2))
  • Replacement plan and schedule Information Needs - discussed during 4/19, 1315, status call - answers highlighted

Design records for as installed piping on Unit 1 & 2 (notifound as9of yet,-stilllooking)

. Pryi'ni, ASMF rpni firpd flow or nressure dron tests for Units 1 & 2 (Wildfoiow-UD) t=

uts e ol Scope

-- ~. ....4 I*MUSW .. 'b, taSK'... .'*AaWmm~tnusasaStfimt." .a. ~..saacr. .. .. 4&5m Outside of Scope Additionl Itemsi.

Status Board Items:

  • Salem ,AFýW buried pip ing ýPI RIT) waiating on PSEG, FEA abnd operblt determination tq eneMC09 Outside of Scope

Outside of Scope