ML103000342

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Document: Operability Evaluation, Opeval, Rev 0, Salem Unit 2 with Handwritten Notes
ML103000342
Person / Time
Site: Salem  PSEG icon.png
Issue date: 10/22/2010
From:
- No Known Affiliation
To:
Office of Information Services
References
FOIA/PA-2010-0334 OP-AA-108-115, Rev 3
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OP-AA-108-115 Revision 3 ATTACHMENT I Operability Evaluation Page 1 of 15 ISSUE IDENTIFICATION:

1.1 1.2 Notification (Order)#: 20460078 (70109482 Op 0010) 1.2 OpEval #: 10-005 Revision: 0 General Information:

1.3 Affected Station(s): Salem Y

1.4 Unit(s)

2 Q1i C +rm A .A;-~;c,1 4 IAr 1.6 Component(s) Affected: 4" NPS Pipe 2AF1019 antj'2AF1013 1.7 Detailed description of what SSC is degraeud or.the nonconforming condition, by what means and when first discovered, and extent of condition for all similarly affected SSCs:.

During S1 R20 Unit 1 refueling outage, corrosion was found on the 4" Auxiliary Feedwater (AFW) buried piping that supplies the 12 andt,l4 steam generators. The corrosion exceeded the minimum wall criteria and the corrosion w*as seen on all excavated piping. This inspection was performed a ,partof planned buried pipeinspections during S1 R20. This operability evaluation assesses the applicability of th findings to the Salem Unit 2 AFW piping 1 Buried AFW Pipingm nteUnit tA i Aily Feedwater pipes connect to the#12 and #14 main feedwater lines in the outer U6 (

A l.rea. T islocation requires the #12 and #14 AFW pipes to travel approximately' r rufn long the edge of the containment building before entering the outer

~~enetration bre'at elevation 94' 8" and 96' 2" for #12 and #14, respectively.

The Guided Wav)e irspectionisof the Salem Unit 1 #12 and #14 Auxiliary Feedwater (AFW) buried piping duringSalem's S1 R20 refueling outage revealed degraded pipe wall conditions e.to external corrosion in excess of the design minimum wall thickness due to heavy external uniform corrosion. The apparent cause of the corrosion was the improper application (or lack4)of0he sp ei!iied pipe coatings, X-Tru-Coat, an o et

.s.ysle nm, 'aBit which was spe

,i e r g d pi.e speciicatons to be aplied at the, wlded joints. Visual inspections of this piping after. excavation showed a lack of coating. The only remnant of coating found was a portion of coal tar which was approximately 9 inches in length and 7 inches in circumference. This piece of coating was in the shape of the 4 inch AFW piping and conformed to that same surface.

The piping is 4-inch NPS, Schedule 80, A106 Gr B seamless carbon steel. It is classified ]as

/Nuclear 3, Seismic Category I, Per the Pipe Specification S-C-MPOO-MGS-0001, SPS 54E, the design Pressure-Temperature limit is 1950 psi at 140 F. The nominal wall thickness is 0.337 inches +/- 12.5%.

i

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OP-AA-108-115 Revision 3 ATTACHMENT I Operability Evaluation Page 2 of 15 Using the Guided Wave inspection results to target specific pipe areas of the 12 and 14 AFW Si1R20, NDE Services initially performed confirmatory UT measurements on pproximately 76 percent of these, UT measurements were non-conforming, hiiinimum wall thickness less than the design minimum wall thickness of 0.278 inches. For the worst case UT measurements, the minimum wall thickness for the #12 AFW buried piping showed a 55 percent loss (0.152 inches). For the #14 AFW buried piping, the greatest loss was approximately 78 percent (0.077 inches). As of 4/1 9/2010 the following number of UT readings were taken:

  1. 14 AFW Line (Upper Pipe): 8,904 readings total. 1,194 are below 0.278"
  1. 12 AFW Line (Lower Pipe): 8,852 readings totl., 92 readings are below 0.278" Removal of sections of the Salem Unit 1 #1'2 and 14 AFW piping during S1,R20 and subsequent visual examinations has validatedthat the corrosion identified aboQeis external.

These inspections also revealed tha is -Tru-Coat an adhered wall portions of the #12 and # 1 AFW piping where it passes into the fuel transfer tub earea. It-isobvious this coaitingsystemwasntt on the buried portfio-ns of LhW~esei andJ 'validatesthat the;corrosion is due to lack of coating.

The ground fill of the AFW piping is not a harsh environrment (harsh with regard to coating),

and there does not appear to be*aib ing/deterioration of coating and the buried pipe environment. retknbtenheisngdeirainocaig Summary of Structural Integrity Assocites ('SIA)Finite Element Analysis Report The underground auxiliary feedwater piping at Salem, Unit 1 was designed to the tmin requiremenntgiven in the B31 .]1 Power Pipi.n'\gCode. B31.1 does not provide specific criteria for the evaluafi of non-nif6rmr wall thickness or local thinning. However, guidance for stress analysiiThaybe takenbfrornthe ASME Code,Section III as described below.

The technical approach'taken herein jsl~selon a h premise on the rms that while in have

  • ~cahized tlinre.

-*'*:* regions thj a design t 6 m~e~d__esign atedthe quirements,he non-uniform stress allowy, waThi thickness of the pipe cr ss-section may be s owno dg se This approach is possible for the.p*'pe section exhibiting thinning w e aini a ter

than tmin surrounds hthinn ion. This approach is similar to the basis for qualifying pipecen-tfriions using branch reinforcement rules in the ASME Code.

Design requirements for Class 3 piping are provided in ND-3600 (similar to B31 .1 rules) of the ASME Code,,Section III [2]. More rigorous analyses are allowed under ND-3611.3:

"Thespec*fic design requirements ofND-3600 are based on a simplified engineering approach.*A more rigorousanalysis such as described in NB-3600 or NB-3200 may be used to calculate the stresses requiredto satisfy these requirements. These calculated stresses must be compared to the allowable stresses in this Subsection. In such cases, the designer shall include the appropriatejustificationfor the approachtaken in the Certified Design Report."

Thus, NB-3200 design by analysis is employed. Based on the linear-elastic finite element analysis results which showed that the section of pipe between AF4T and AF5T was C:\Documents and Settings\rjc\Local Settings\Temporary Internet Files\Content.Outlook\F6ZV6HAE\OP

OP-AA-1 08-115 Revision 3 ATTACHMENT I Operability Evaluation Page 3 of 15 bounding, it was required to perform additional analysis only for that section of pipe in order

,to show operability. The more rigorous analysis employed is described in Section NB3228.1, Limit Analysis. Specifically Section NB-3228.1 states that limits on Local Membrane Stress Intensity need not be satisfied at a specific location if it can be shown by limit analysis that the specified loadings do not exceed two-thirds of the lower bound collapse load. Also, NB-3228.1 states that the yield strength to be used in this calculation is 1.5Sm. In this evaluation, the value of yield strength is equal to 1.5S, where S is taken as the value of Sh, 15.0 ksi, from the original 1967 B31.1 Power Piping Code. Thus, a yield strength of 22.5 ksi is used.

The thinned section of pipe is modeled Iusing the as-fournd wall thickness values for the region s ec TE)DI 201 which includes a minimum wall thickness- f 0.077 inches. A pressure load of 1.5 times the specified desi-gn-pie ei -p 1.5*[1310psia-14.7psi]) to-tl*-ph pe.*;*,, .

The results of the finite element analysis show*that the thinned pipe in this section remains structurally stable at 1.5 times the specified design pressure and therefore passes the limit load analysis.

Unit 2 Buried AFW Piping: *Y$,<'

At Salem Unit 2, the AFW discharge lines supplying the #22 and #24 SGs are also buried and run alongside the Unit 2 containment similar to the Uniti 1 #12 and 14 AFW lines. The piping and coatings specified for Unit 2 AFW are identical to hose in Salem Unit 1 AFW buried piping. iY December 1994 Inspection .

In December 1994, three areas of the buried Salem Unit 2 AFW piping were excavated due to a concrn over water entering the Williamson penetration seals into Outer Penetration area. The concern was that this water could potentially be coming from a degraded buried

  1. 22 and/or #24 AFW line.j Work orderd(941017262) created to excavate specific areas of the yard area containing these buried lines to rule out any degradation of the #22 or #24 AFW lines and prove that ground water was the source of the ingress.

SOnce excavation was complete in the three areas identified, coatings on these lines were inspected and photogr ere a e . -0877, the coal tar coating on the

  1. 22 and #24 Aux Feeklines app ared to e in cellent condi It was noted that some of the coating had adhered In one ofethe excavated areas, the coal tar coating was removed from the #22 and #24 AFW piping to allow for UT examination. These UT examinations revealed the following:

Upper AFW Pipe (#24):

No degradation of the piping was observed, with 50% of the piping at or above nominal thickness. No thickness readings below the manufacturer's tolerance of 87.5%. The lowest recorded value was 0.321" which was within the manufacturer's tolerance. R C:\Documents and Settings\rdc\Local Settings\Temporary Internet Files\Content.Outlook\F6ZV6HAE\OP

"*.7t OP-AA-108-115 Revision 3 ATTACHMENT 1 Operability Evaluation Page 4 of 15 Lower AFW Pipe (#22): Qdy ,

No degradation of the piping with 55% of the piping at or above nominal thickness, no thickness readings below the manufacturer's tolerance of 87.5%. The lowest recorded vp~lpe was 0.306" which was within the manufacturer's tolerance. Reference Post-inspection:

Any exposed carbon steel was prepped and recoated, and included the areas of minor flaking a trcton ad taio rceursTwo moved coats for UTo* asi as performed lAW work were applied order e-x`pv *-d meta re n 'uwr See Repo 4-877).

Recent AFW Excavation Inspecti on On 4/22/2010, several areas were excavatedtinspect a sampling of Unit 2 Aux Feed pipi that was not part of the 1994 inspection. Salem Buried Pipe Program Enzgineer performed a visual inspection of the Salem Unit 2 Auxili*r*'Feedwater Buried Pipe for the No. 24 Aux Feed Train going to No. 24 Steam Generator. The subject pipe was unearthed in the Fuel Transfer Area just as it exits the building heading North towards the Outer Penetration. This 4" diameter pipe was completely exposed for an approximate 2 foot length at the wall penetration. Only the No. 24 line was exposed during this examination. The Bitumasitic coating was fully intact on the pipe, and showed no signs of deterioration or any flaking.

Visual inspection included a look at the appearance, and running a hand over the pipe surface looking for loose cqo*a*tir-fac-of adhesion. Therewas no loose coating or lacko adhesion, the coating wafin excellentconditi .

Pooling Water Notification 20459941 identifid that pooling water was found in 'the area between Unit 2 containment and fuel handlig building. Sampling results by chemistry detected measurable traces of ammonia. The results of an evaluation stated that the source of the water was not from the Unit 2 Auiliary*Feedwater system. erce AFW Temperature Difference On 4/20/2010 temperatures were taken on AF piping at various points upstream of the AF23 check valves. The purpose of this evolution was to determine if any of the AF lines is.

experiencing back leakage (which could be an indication of thru-wall leak). The results of the analysis shows that the temperatures measured seem appropriate for normal conduction of heat through the valVe plug into fluid within the pipe. The pipe temperatures would be expected to stay elevated for longer lengths if there were a constant source of heated water moving through the pipe. Additionally, a review of operator log entries, SAP, and surveillance test results indicates that there has be as of inventory in the AFWST over

". the previous operating cycle.

Analysis The piping is 4-inch NPS, Schedule 80, A106 Gr B seamless carbon steel. It is classified as Nuclear 3, Seismic Category I. Per the Pipe Specification S-C-MPOO-MGS-0001, SPS 54E, the design Pressure-Temperature limit is 1950 psi at 140 F. The nominal wall thickness is 0.337 inches.

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OP-AA-108-115 Revision 3 ATTACHMENT I Operability Evaluation Page 5 of 15 To assess the available margin in the degraded Salem Unit 1 Piping, the maximum credible operating pressure was developed using all AFW system operating conditions (see SAP 70108698-0100). The resulting pressure is 1275 psi. The pipe wall tmin for this pressure is 0.185 inches. This operating pressure evaluation also applies to Salem Unit 2.

Since the AFW piping was found to be in good condition during 1994 inspection, and again during the current inspection, an average corrosion rate of 6 mils/year is conservatively assumed. The proposal is to perform excavation and inspections during the upcoming Unit 2 refueling outage (S2R1 8) scheduled for April 2011. This is a span of 16.5 years from the last inspection in 1994. The projected wall loss assuming a. corrosin rate of 6 mils/per year is 0.099 mils (16.5 x 0.006). The projected wall thickness would be 0.207, which meets the minimum thickness requirement of 0.185 inches to support maximumr credible operating pressure of 1275 psi Note that this projection assumes a nominal corrosion rate, even though spot inspections performed in 1994 atfand aain in April 2010 showed*d that coating was intact and in good condition. Corrosion rate~for, sound coated carbon steO'l 'piping is zero.

Coating Life Span ". "

Proper preparation of the carbon steel piping a'ndapplication of the coating will ensure proper adherence to the piping. The recent inspections per'eformpd -o-42/2010 of piping buried since construction showed that the coating was intact an good ondition, and the piping showed no indication of degradati*nior corrosion. Therefore, boating is assumed to remain intact until next Unit 2 refueling outage. 11(f q-N)6 In-service testingp dR s The latest in-service testing*or Unit 2 Pumps and valves are provided below. Results of all testing was SAT.. _________________ __ _

Procedure Compronent Work Order Date Re s 05 '2! 2F2Moetor Dnrive* Pumps 50114298 11/5/2001 SAT

,S2.OPE-SO.AF-:0006 AF23 Stop Ch*ec*k lves 50128109 01/24/201 SAT 52.OP-SQO.AF-0007 23 Turbine Driven Pump 50113100 10/13/2009\ SAT Conclusion Considering the positive inspection findings for both coatings and UT readings of the Salem Unit 2 #22 and #24;AFW buried lines, coupled with fact it is apparent that the Salem Unit 1

  1. 12 anid 14 AFW lines were not coated or improperly coated, there is reasonable assurance that the buried #22 and #24 AFW lines are protected from corrosion at this time by the coating system applied and are structurally sound, and the coating is assumed to remain intact until next Unit 2 refueling outage. Per the table above, recent In-service testing results for the AFW components were all SAT.

Based on the above information, it is concluded that Unit 2 AFW buried piping can perform its intended function until the next Unit 2 refueling outage (S2R18).

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OP-AA-1 08-115 Revision 3 ATTACHMENT 1 Operability Evaluation Page 6 of 15 Future Actions and/or Compensatory Actions Implement planned inspection per the buried pipe program in next outage of sufficient duration or S2R18. Perform Guided Wave examinations of the #22 and # 24 AFW buried piping during the next Unit 2 refueling outage - S2R18 As such, Guided Wave inspections of the Unit 2 AFW buried piping will be performed at locations to survey for areas of general or pitting corrosion. The results from the Guided Wave inspections will be used to target areas of interest for follow-up direct visual and confirmatory UT!irnspections to determine pipe minimum as-found wall thicknesses. Any portion of the piping if found unacceptable will be replaced.

2. EVALUATION: '

2.1 Describe the safety function(s) or safety support functibn(s) of the SSC, As a minimum the following should be addressed!*as applicable, in describing the SSC safety or safety support function(s): \* / VS UFSAR Section 10.4.7.2: Auxiliary Feedwater The AFW System serves as a backup system for supplying feedwater to secondary side of the The available. steam AFW;-System times generatorsisatrelle *)p' /* / MainFeddaater whethe *:t System is not ven availythems duponto prevent core damage and system overpressurization in the event of acceidets such as a loss of normal feedwater or a secondary-system pipe rSupture, and to. provide a means for plant cooldown.

Ewith ne turbine:driven and two motor-driven auxiliary feed pumps. Eachmotor-ldive~npu"p-discharges to two steam generators with a normally isolated (21 and22AF923 valves) :cross-c6nnect line joining the motor-driven pump disctianrge6 headeirs: The turbine-drivemnpump feeds all four steam generators.

7Feedwaier-1w, is confrolled from the Control Room by remotely operated flow control

'valves in the 'upply liels to each steam generator. In order to prevent a runout

" condition of the.,metor drivehpumps the steam generator flow control valves (AF21's) modulates to control the motor-driven auxiliary feedwater pump discharge pressure.

The minimum performance limits required for the auxiliary feedwater pumps to satisfy thede'iiign bases,anailyses, as verified during quarterly (minimum flow/recirculation) and Full Flow Technical Specification Inservice Testing, are included below. Note that these values account for test instrumentation uncertainties.

S2.RA-ST.AF-0002 (*22AFP Min Flow Test)

Min Flow Test 21 motor-driven AFWP* 160 gpm and 1369 psid 22 motor-driven AFWP 160 gpm and 1389 psid 23 turbine-driven AFWP 400 gpm and 1506 psid at 3600 rpm C:\Documents and Settings\rjc\Local Settings\Temporary Internet Files\Content.Outlook\F6ZV6HAE\OP

OP-AA-108-115 Revision 3 ATTACHMENT 1 Operability Evaluation Page 7 of 15 S2.RA-ST.AF-0005 (*22 AFP Full Flow Test)

Full Flow Test 21 motor-driven AFWP 440 gpm and 1184 psid 22 motor-driven AFWP*

  • 450 gpm and 1114 psid 23 turbine-driven AFWP 880,gpm and 1269 psid at 3600 rpm All auxiliary feed pumps normally take suction from the, auxiliary feed storage tank. A safety grade, automatic low pressure trip is prov ided as backup protection for each pump in the event that tornado missile damage to the auxiliary feedwater storage tank results in loss of suction pressure. To protect against spurious activation, this trip will be made operable only during "tornado warnings" issued by the National Weather Service. The tank has sufficient capacity to allow residual heat removal for 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. 'Backup water sources for the auxiliary feed pumps are the two demineralized water storage tanks (500,000 gallons capacity each), the two fire protection and domestic water storage tanks (350,000 gailons capacity each) and the station Service Water System, which must first have a spool piece installed. The quality of water from these sources is lower and is therefore intended for, use only in the event of emergency situations.
  • Does theSý,SCreceive/initiate an RPS orESF actuation signal?

YES. The/Auxiliary Feedwater System (AFWS) is an Engineered Safeguards System (ESF). Tlie motor driven auxiliary Feedwater pumps (MDAFPs) start automatically due to (1) trip oftth mainFeedwater[pumps (LONF), (2) Safety Injection signal, and (3) a Low.-Low signal Low-Low sdriven two MDAFPs are loaded onto theauxiliaryar from any oneSG.,The emergency

/dieseqlgeneratorsiby. the automatic:'loa sequencer. The turbine driven auxiliary

,eid"ePump (TDAFP starts automatically on (1) a Low-Low level in two of the four onSGs, (2) Lossr co125VE "Control power, (3) Loss of Control Air, and (4) undervoltage

on the reactorc0olant pump group buses on I out 2 logic. For anticipated transients
without Chapter scram (ATW) events" which are not design basis transients analyzed in 15 of the FSAR, Westinghouse plants such as Salem have an ATWS Mitigation System Actuation .. irc 'iuitry(AMSAC) to initiate a turbine trip an actuate auxiliary feedwater flow independent of the Reactor Protection System or the ESF Actuation System (ESFAS). When SG level drops below the AMSAC set point in 3 of 4 SGs, AMSAC initiates tripping the turbine, initiates AFWS, and isolates the SG blowdown and sample lines. AMSAC is non-safety related.
  • Is the SSC in the main flow path of an ECCS or support system?

NO. The AFWS is not an Emergency Core Cooling System (ECCS) or an ECCS support system. The AFWS serves as a backup system supplying feedwater to the secondary side of the SGs when Main Feedwater system is unavailable. It is relied upon to prevent core damage and RCS overpressurization in certain design basis accidents such as Loss of Offsite Power (LOOP), LONF, Feedwater Line Break (FWLB), Main C:\Documents and Settings\rjc\Local Settings\Temporary Internet Files\Content.Outlook\F6ZV6HAE\OP

OP-AA-108-115 Revision 3 ATTACHMENT 1 Operability Evaluation Page 8 of 15 Steam Line Break (MSLB), Steam Generator Tube Rupture (SGTR), or Loss of Coolant Accident (LOCA) by providing a means for plant cooldown from normal operating conditions to initiation of low pressure residual heat removal systems. It functions during startup, shutdown, and hot standby (HSB).

  • Is the SSC used to:

Maintain reactor coolant pressure boundary integrity?

YES. The Auxiliary Feedwater system supplies water to the SGs for reactor decay heat removal when the normal Feedwater sources are unavailable due to loss of offsite power (LOOP) or other malfunction. By maintaining water levels in the SGs and thus ensuring an adequate heat sink, the AFWS functions to remove decay heat, reactor coolant pump heat, and sensible heat during plant cooldown. In addition, the AFW system functions to prevent overpressurization of the RCS, thereby protecting the reactor coolant pressure boundary (RCPB) initegrity.

  • Shutdown the reactor?

NO. The AFWS does not provide a reactivity control safety function for shutting down of the reactor; although it does help to cooldowntme reactor. The AFWS does not affect the rod control system orthe alternative b*r\n chemical shim system that control reactivity in the core. Byproviding the SG secondary side heat sink medium capable of receiving heat transf erfrom the reactor cohlant system, the AFWS has an indirect positive reactivity effect,.by cooling and thus inccr'easing the density of the reactor coolant,,neii6'ri moderator. /

YES. The-licensing basis for safe shutdown at Salem is hot standby (HSB). The AFWS must performits safe shutdown function to maintain the plant in HSB. The AFWS can be manually controlled to maintain HSB conditions until cooldown can be established.

The AFWS is provided with sufficient water from the Auxiliary Feedwater Storage Tank

.AFST..toallow the SGs to provide decay heat removal for 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. In addition, backup water sources are provided from the Demineralized Water Storage Tanks (DWSTs), the 2 Fire Protection,Water Storage Tanks (FPWSTs), and a normally disconnected connection to the Service Water system for use in an emergency in the event of a

§seismic event that inicapacitates AFST, DWSTs, and FPWSTs. During normal coolqown, each of the MDAFPs has the capacity to remove heat from the SGs at a sucfficent rate to prevent RCS overpressurization and to maintain SG levels to prevent thermal-cycling.

Prevenhtor P mitigate the consequences of an accident that could result in offsite exp6sures comparable to 10 CFR 50.34(a)(1), 10 CFR 50.67(b)(2), o/a 10 CFR 100.11 guidelines, as applicable. v V YES. The AFWS performs a safety function in mitigating design basis accidents, including LOOP, LONF, FWLB, MSLB, SGTR, and small break LOCA (SBLOCA) b supplying adequate feedwater to the secondary side of the Steam Generators to prevent overheating the reactor coolant system and to provide a means for achien. n6 plant cooldown to initiation of the residual heat removal system. Depending on theý design basis accident, the AFWS either maintains or limits feedwater to the SGs. For C:\Documents and Settings\rjc\Local Settings\Temporary Internet Files\Content.Outlook\F6ZV6HAE\OP

OP-AA-108-115 Revision 3 ATTACHMENT 1 Operability Evaluation Page 9 of 15 the SBLOCA, LONF, and LOOP/LONF, the AFWS must maintain adequate feedwater.

For the FWLB, the AFWS must preserve inventory while maintaining level. For the MSLB and SGTR events, the AFWS must limit feedwater flow as too much water delivery will result in overcooling the reactor coolant system or overpressurization of the containment.

  • Does the SSC provide required support (i.e., cooling, lubrication, etc.) to a TS required SSC?

YES. During normal plant cooldown, the AFWS removes sufficient heat from the SGs to prevent overpressurization of the RCS and to maintain SG levels sufficient to prevent thermal cycling.

  • Is the SSC used to provide isolation between safety trains, or between safety and non-safety ties? -

NO. The AFWS does not perform an isola1tion function per se; however, Whenever either the MDAFPs or the TDAFP automatically starts, a signal is sent to the isolation valves of the Steam Generator Blowdown and Sampling Systems to close. The isolation signal to the Sample System isolation valves can be bypassed using a keylocked switch located in the Control Room.

  • Is the SSC required to be operatedmanuallyto mitigate a design basis event?

NO. The AFW pumps can. be operated manually at their local control panel or from the main Contro IRoom. Autom' atic initiation signals are designed to prevent system malfunction given a single failure. AFW flow is controlled from the Control Room using remotely-perated flow control valves AF21's) in the supply lines to each SG. Safety-related flow indication to*each-SG is prdiided in the Control Room. The flow control valves have reducedgcapity-tom itohte maximum flow under certain plant coffditions. *

/ Have all specified safety functions described in TS been included?

YES. Salem T/Ss require thiat at least three independent AFW pumps, their associated manual activation switches in.the Control Room, and their flow paths are operable in Modes 1 though 3. The two MDAFPs must be capable of being powered from separate vital' busses and the TDAFP must be capable of being powered from an operable steam supply system. Operability of the AFWS ensures that the Reactor Coolant System can be cooled down to less than 350 F from normal operating conditions in the event of a total loss of offsite power (LOOP).

Have all safety functions of the SSC required during normal operation and potential accident conditions been included?

YES. The AFWS safety functions include LONF, FWLB, MSLB, LOOP, and LOCA during accident conditions and plant cooldown during normal plant conditions. The AFWS supplies water to the SGs for reactor decay heat removal if the normal Feedwater sources are unavailable due to loss of offsite power or other malfunctions.

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OP-AA-108-115 Revision 3 ATTACHMENT 1 Operability Evaluation Page 10 of 15

  • Is the SSC used to assess conditions for Emergency Action Levels (EALs)?

NO. The AFWS is not used to assess conditions for EALs.

2.2 Describe the following, as applicable: (a) the effect of the d*6*dgraded or nonconforming condition on the SSC safety function(s); (b) any requirements or commitments established for the SSC and any challenges to these; (c) the circumstances of the degraded/nonconforming condition, including the pssible"failure mechanism(s);

(d) whether the potential failure is time dependent and whether the condition will continue to degrade and/or will the potential consequences increase; and (e) the aggregate effect of the degraded or nonconforming condition in light of other open OpEvals:o Table: List of Existihg.OpEvyls NOTF/ORDER ENTRY DESCRIPTION

  • OWNER STATUS EXPECTED NUMBER DATE CLOSURE 80094618-issued, SI/2 ECCS room need orders07-033 80094618 9/07/07 cooler thermnost*ts Bhard planned 08/11 (DCP 80094618 and Bhardwaj 80095613- issued,
  • 77 80095613) - need orders

______ <planned

- / * .. 230V Motor*;** Operated SI1/S2 On-Line 80099509 to DCP be 08-040 7008783t183 8/08/08 Valve - degraded Ciarlante 12/23/10 K '*: "*:.*,;.*,.*!**

  • vo%*t

. ,\

voltage* . planned, scheduled,

___________........______ installed 09-09 60084229 4/07/09; CAA14/CAA17/CAA20 Hassler Perform Inspections 5/31/10

  1. 4o Replace door seal 09-019 60085180 S*:* 8/110/09 ;*.::;,,"WW SRW watertight door Hassler 0022 5/21/10

'0 9 021 1 70103767, 11/5/09 Can Liner Curran Repair in $2R18 $2R18 PR Heater busses E Procure new panel 094023*"11&9/0970104221 G3 R. Smith door design/ 6/1/10 ovrhatn Implement new

  • , overheating _design 10-01 * * ::* 21 SI**"-

-[*"*%*Develop repair plan 10-0 01,t06347 *1/28/10 pump oil leak Hummel RpiOlLek 9/27/10

______ ________ _____________Repair Oil Leak 10-002 60089385 003/19/10 #4WHayman Perform repairs 4/27/10

_*Temp

_____________ Controller 22SW34 Valve failed 10-003 20455408 3/25/10 ASME code reverse Hassler Perform repairs 5/30/10 flow check 10-004 20457356 4/07/10 #3 SW Bay Vent temp Hayman Perform repairs 9/30/10 controller for 1SWV3 A) THE EFFECT OF THE DEGRADED OR NONCONFORMING CONDITION ON THE SSC SAFETY FUNCTION(S)

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OP-AA-108-115 Revision 3 ATTACHMENT I Operability Evaluation Page 11 of 15 The nonconforming condition potentially affects the structural integrity of the AFW discharge piping, reducing the margin of the Tmin wall thickness for a given pressure and would limit the maximum pressure to a value less than the design pressure. Based on an assumed constant corrosion rate, the wall thinning reduces the life expectancy of the buried pipe. If structural integrity is lost and a breach in the pipe occurs, the AFW system can no longer fully perform its design safety function. It should be noted that there has been no identifiied active leak reported.

B) ANY REQUIREMENTS OR COMMITMENTS ESTABLISHED"F9J4HE SSC AND ANY CHALLENGES TO THESE 4.'

The requirement associated with minimum wall thickness (Tmin) for buried AFW pipe is governed by the ANSI B31.1, 1967 Edition, Power Piping code.

C) THE CIRCUMSTANCES OF THE DEGRADED"NONCONFORMING CONDITION, INCLUDING THE POSSIBLE FAILURE MECHANISM(S)~

The degradation of the auxiliary feed water piping -Eft',Unit 2 is substantially less than that at Unit 1. Based on the existingdata, it isconcluded that tle7AFW piping will be able to perform its intended designfunction'at least until the next Unit 2 refueling outage (April 2011) when an extensive investigation will be performed. A complete loss of wall thickness would result in rupture in the pipe. Any rupture will result in loss of cooling of the steam generators.

D) WHETHER THE POTENTIAL FAILURE IS TIMEDEPENDEN-AND WHETHER THE CONDITION WILL CONTINUE TO DEGRADE AND/OR WILLTHE POTENTIAL CONSEQUENCES INCREASE; AND The potential failure ofthe pipe is time dependent based on the assumed corrosion rate. Based on earlier assessments of carbon steel corrosion due to exposure to brackish Service Water, the buried AFW pipe wall thickness will continue to degrade 6 mils peryearuuntil the pipewll no longer be capable of supporting the maximum *redibl.e*perating prewsurewithout margin to eminent failure.

I-lTHEAGGREGATEEFFECT OF THE DEGRADED OR NONCONFORMING CONDITION IN LIGHT OF. OTHEROPEN OPEVALS (SEE TABLE OF OPEN OPEVALS ABOVE)

The aggregate impact ofthe non-conformance being evaluated was assessed against outstanding OpEVals listed in the Table above. Each of the ODs was

\reviewed in depth, for the description of condition and the basis of the operability determination to'determine if the non-conformance described in this OpEval will make any SSC-covered in the other outstanding ODs inoperable or degraded. In conclusion, the OpEval discussed herein has no aggregate impact on any SSC safety function or other OD currently open.

YES NO 2.3 Is SSC operability supported?

Explain basis (e.g., analysis, test, operating experience, [X] [I engineering judgment, etc.):

Summary SIA Finite Element Analysis Report The preliminary analysis of the Salem Unit 1 underground auxiliary feedwater piping is complete. The analysis evaluated the region specified in S-TODI-2010-0005 which C:\Documents and Settings\rjc\Local Settings\Temporary Internet Files\Content.Outlook\F6ZV6HAE\OP

OP-AA-108-115 Revision 3 ATTACHMENT 1 Operability Evaluation Page 12 of 15 includes a minimum wall thickness of 0.077 inches. A Limit Analysis was performed as described in NB-3228.1. NB-3228 allows relaxation of basic stress limits if plastic analysis is used. An elastic-perfectly plastic finite element analysis was performed and the results show that the criterion specified in NB-3228.1 is satisfied.

If 2.3 = NO, notify Operations Shift Management immediately.

If 2.3 = YES, clearly document the basis for the determination. .7 7 YES NO 2.4 Are compensatory measures and/or corrective actions required? [X] [ X]

If 2.4 = YES, complete section 3.0 (if rNO* N/A section 3.0).

Reference Documents:.4-2.4.1. Technical Specifications Section(s):

T/S 3/4.7 Plant Systems, LCO 3.7.1.2, Auxiliary Feedwater System 2.4.2. UFSAR Section(s):

3.9.4: Inservice Te'stip Pumps and Valves 10.4.7.2, Auxiliary'Feedwat'er System 15.2.8, Loss of Normal Feedwater

  • 15.2.9, Losssof Offsite Power 15.3.1, Lo~ss*£f*eator* Co~anfrom to Station Auxiliaries iare (LOP)

LP

.... osf oColant fromSmall Ruptured Pipes (SBLOCA) 15.4.1, Major Rea ctorCoolant Systemi Pipe Ruptures (LBLOCA) 15.4.2, Major Seconary System Pipe Rupture (MSLB) 15.4.3, Major Rupture of Main Feedwater Line (FWLB) 7 *1*15.4.4, Steam Generator Tube Rupture (SGTR) 2.4.3 . Other:

Technical Evaluation 70108698, Rev. 0 Technical Evaluation 20459941 Potential Water Sources Inner Mechanical Penetration ANSI B3,1.1, 1967,Ed., Power Piping DWG 205336 Sheet I Rev. 49 DWG 2182n33 Sheet 1 Rev. 11 S-C-MPOO-MGS-0001, SPS54, Rev. 6, Piping Schedule, Auxiliary Feedwater S-C-AF-MDC--0445, Rev. 3, Auxiliary Feedwater System Hydraulic Analysis S-C-F400-MDC-0096, Rev. 4 Auxiliary Feedwater Storage Tank (AFWST) Capacity S-C-A900-MDC-005, Rev. 0, Pipe Wall Thickness Calculations (Info Only)

S2.OP-ST.AF-0002 Rev 18 S2.RA-ST.AF-0001 Rev. 6 (21 Aux Feed Pump)

S2.RA-ST.AF-0002 Rev. 9 (22 Aux Feed Pump)

S2.RA-ST.AF-0005 Rev. 9 C:\Documents and Settings\rjc\Local Settings\Temporary Internet Files\Content.Outlook\F6ZV6HAE\OP

OP-AA-108-115 Revision 3 ATTACHMENT 1 Operability Evaluation Page 13 of 15 SC.DE-BD.AF-0001(Q), Rev. 0, Auxiliary Feedwater System (Info Only)

[SIA Finite Element Analysis Report]' S 005 SCI-94-877 LTR dated 12/16/1994 - Excavated Auxiliary feedwater Piping Walkdown/Disposition of Coating Requirements 20459689 Work Order 941017262 Duane Arnold Energy Center Relief Requests NDE-R004 an0'dNDE-RO07 (Info Only)

3. ACTION ITEM LIST:

If, through evaluating SSC operability, it is determined that the degraded or nonconforming SSC does not prevent accomplishment of the specified safety functio*(s) in the TS and the intention is to continue operating the plant in thatfcbndition, then record*below, as appropriate, any required compensatory measures to support operability anid/or corrective actions required to restore full qualification. For corrective actions, document when the actions should be completed (e.g., immediate, within next 13week period, next outage, etc.)

and the basis for timeliness of the action. Corrective action timeframes longer than the next refueling outage are to be explicitly justified as pa, f.of the'OpEval or deficiency tracking documentation being used to perform the corrective a'Ction.

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.4

.1 OP-AA-1 08-115 Revision 3 ATTACHMENT 1 Operability Evaluation Page 14 of 15 Corrective Action #1: Perform Guided Wave examination and visual examination of the excavated area for the #22 and # 24 AFW buried piping during the next Unit 2 refueling outage - S2R18. The results from the Guided Wave inspections will be used to target areas of interest for follow-up direct visual and confirmatory UT in~spections to determine pipe minimum as-found wall thicknesses. Replace if necessary;,"lllnon-conforming buried AFW piping. Work Order 60084161 is created to performithis task.

Responsible Dept./Supv.: TBD Action Due: S2R18 Refueling Outage (April 2011)

Action Tracking #: Work Order 60084161 /4F2 Corrective Action #2:

Responsible Dept./Supv.:

Action Due:

Basis for timeliness of action:

Action Tracking #:

4., SIGNATURES:

4.1 Preparer(s) Mar*.Puher Date 04/22/2010 Robert Down Date 04/22/2010 4.2 Reviewer Kiran Mathur Date 04/22/2010 (10 CFR 50.59 screener qualified or active SRO license holder) 4.3 Sr. Manager'Design Engr/Designee Concurrence Date 4.4 Operations Shift Management Approval Date 4.5 If the OpEval is to declare a Shutdown Safety System or component Operable but Degraded, then the following signatures are required: (CAPR 70103591)

C:\Documents and Settings\jc\Local Settings\Temporary Internet Files\Content.Outlook\F6ZV6HAE\OP

OP-AA-108-115

Revision 3 1

ATTACHMENT Operability Evaluation Page 15 of 15 Operations Director ..... _Date Engineering Director __Date

  • Shutdown Safety Manager " Date
  • When in Modes 4, 5, 6, Defueled (SA) or Modes 3, 4, 5 (HG).

4.6 Ensure the completed form is forwarded to the OEPM for processing and Action Tracking entry as appropriate.

5. OPERABILITY EVALUATION CLOSURE: .

5.1 Corrective actions are complete, as necessary, and the OpEval is ready for closure Date __ _ _ _ _

(OEPM) 5.2 Operations Shift Managementi÷ Approval ______________________________ Date 5.3 Ensure the completed form is forwarded to the OEPM for processing, Action Tracking entry, and cancellatio'* of any open compensatorymeasures, as appropriate.

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