ML103000339

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Document: Operability Evaluation, Opeval, Rev 0 Salem Unit 2
ML103000339
Person / Time
Site: Salem  PSEG icon.png
Issue date: 10/22/2010
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- No Known Affiliation
To:
Office of Information Services
References
FOIA/PA-2010-0334 OP-AA-108-115, Rev 3
Download: ML103000339 (15)
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OP-AA-1 08-115 Revision 3 ATTACHMENT 1 Operability Evaluation Page 1 of 15

1. ISSUE IDENTIFICATION:

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

1.3 Affected Station(s): Salem

1.4 Unit(s)

2

1.5 System

Auxiliary Feedwater (AF) 1.6 Component(s) Affected: 4" NPS Pipe 2AF1019 and 2AF1013 1.7 Detailed description of what SSC is degraded or the nonconforming condition, by what means and when first discovered, and extent of condition for all similarly affected SSCs:

During S1R20 Unit 1 refueling outage, corrosion was found on the 4" Auxiliary Feedwater (AFW) buried piping that supplies tie 12 and 14 steam generators. The corrosion exceeded the minimum wall criteria and the corrosion was seen on-all excavated piping. This inspection was performed as part of planned buried pe inspections during S1 R20. This operability evaluation assesses the applicability of the findings to the Salem Unit 2 AFW piping Unit 1 Buried AFW Piping Auxiliary Feedwater pipes connecttothe #12and #14 main feedwater lines in the outer

/penetration area. This7 location requires the #12 and #14 AFW pipes to travel approximately 430' underground along the edge of the containment building before entering the outer penetration area at elevation 94' 8" and 96' 2" for #12 and #14, respectively.

The Guided Wave inspections of the Salem Unit 1 #12 and #14 Auxiliary Feedwater (AFW) buried piping during Salem's Si R20 refueling outage revealed degraded pipe wall conditions due 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 lack)of the specified pipe coatings, X-Tru-Coat, an adhered polyethylene protection system, r**dBturmnastic, which was specified per drawings and pipe specifications to be applied at the welded 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, f the design Pressure-Temperature limit is 1950 psi at 140 F. The nominal wall thickness is 0.337 inches +/- 12.5%.

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OP-AA-1 08-115 Revision 3 ATTACHMENT 1 Operability Evaluation Page 2 of 15 Using the Guided Wave inspection results to target specific pipe areas of the 12 and 14 AFW piping during S1 R20, NDE Services initially performed confirmatory UT measurements on 378 grid areas. Approximately 76 percent of these UT measurements were non-conforming, having a minimum 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 4119/2010 the following number of UT readings were taken:

  1. 14 AFW Line (Upper Pipe): 8,904 readings total. 1,19N are below 0.278"
  1. 12 AFW Line (Lower Pipe): 8,852 readings total. 192 readings are below 0.278" Removal of sections of the Salem Unit 1 #12 and 14 AFW piping during S1R20 and subsequent visual examinations has validated that the corrosion identified above is external.

These inspections also revealed that there is evidence ofthe X-Tru-Coat, an adhered polyethylene protection system only on the thru wall portions of the #12 and # 14 AFW piping where it passes into the fuel transfer tube area. Itis obvious this coating system was not on the buried portions of these lines andwlidates that the corrosion is due to lack of coating.

The ground fill of the A.W piping i not a harsh environment (harsh with regard to coating),

and there does not appear to be a correlation between the missing/deterioration of coating and the buried pipe environment. _

Summary of Structura Inteqrity Associates (SIA) Finite Element Analysis Report The underground auxiliary feedwater piping at Salem, Unit 1 was designed to the tmin requirement given in the B31.1 Power Piping Code. B31.1 does not provide specific criteria for the evaluati6n of non-uni=frm wall thickness or local thinning. However, guidance for stress analysis may be taken from the ASME Code,Section III as described below.

The t / approach taken herein is based on the premise that while piping may have hlocalized thinned regions that violate the design tmin requirements, the non-uniform wall thickness of the pipe cross-section may be shown to meet design stress allowables. This approach is possible for the pipe section exhibiting thinning when a remaining wall greater than tmin surrounds the thinned*region. This approach is similar to the basis for qualifying pipe penetrations 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:

"The specif esign 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 required to 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 approach taken 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\TLO1\Local Settings\Temporary Internet Files\Content.Outlook\HDZV6AOE\OP EVAL 10-005 Salem U2 Buried AFW Pioe.docc

OP-AA-108-115 Revision 3 ATTACHMENT 1 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 using the as-found wal* thickness values for the region specified in S-TODI-2010-0005 which includes -a inimum wall thickness of 0.077 inches. A pressure load of 1.5 times the specified design pressure isapplied (1943 psi 1.5*[1310psia-14.7psi]) to the pipe.

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 passe~s the limit load analysis.

Unit 2 Buried AFW Piping:

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 Unit 1 #12 and 14 AFW lines. The piping and coatings specified for Unit 2 AFW are identical to those in Salem Unit 1 AFW buried piping.

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

  1. 22 and/or #24.AF. ine. Work order (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.

Once excavation was complete in the three areas identified, coatings on these lines were inspected and photographs were taken. Per Report SCI-94-0877, the coal tar coating on the

  1. 22 and #24 Aux Feed lines appeared to be in excellent condition. It was noted that some of the coating had adered very well and in other areas it had flaked off.

In oneo6f the 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. ere C:\Documents and Settings\TLOl\Local Settings\Temporary Internet Files\Content.Outlook\HDZV6AOE\OP EVAL 10-005 Salem U2 Buried AFW PiDe.docc

OP-AA-1 08-115 Revision 3 ATTACHMENT I Operability Evaluation Page 4 of 15 Lower AFW Pipe (#22):

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 value was 0.306" which was within the manufacturer's tolerance.*eferenceý Post-inspection:

Any exposed carbon steel was prepped and recoated, and include the areas of minor flaking and sections where coating was removed for UT. All work was performed lAW work order instructions and station procedures. Two coats of Bitumastic 50 were applied over exposed metal surfaces lAW work order instructions. (See Report SI-94 -877).

Recent AFW Excavation Inspection On 4/22/2010, several areas were excavated to inspect a sampling of Unit 2 Aux Feed piping that was not part of the 1994 inspection. Salem Buried Pipe Program Engin*eer performed a visual inspection of the Salem Unit 2 Auxiliary Feedwater Buried Pipe for the No. 24 Aux Feed Train going to No. 24 Steam Generator. The subjetpVi pe was unearthed in the Fuel Transfer Area just as it exits the building heading Northtowards the Outer Penetration. This 4" diameter pipe was completely exposed for an aprimate 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 coating orlack of adhesion There was no loose coating or lack of adhesion, the coating was in excellent condition. WAIING FORU Pooling Water, Notification 20459941 identified that pooling water was found in the area between Unit 2 containment and fuel handling 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 Auxilia.F.edwate. sstemre.feren 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 been no appreciable loss 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-1 08-115 Revision 3 ATTACHMENT 1 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 tmln 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 milslyear is conservatively assumed. The proposal is to perform excavation and inspections during the upcoming Unit 2 refueling outage ($2R18) scheduled for April 2011. This is 9 span of 16.5 years from the last inspection in 1994. The projected wall loss assuming a corrosion rate of 6 mils/per year is 0.099 mils (16.5 x 0.006). The projected wall thickness would 0.207,

.e which meets the minimum thickness requirement of 0.185 inches to support maximuump credible operating pressure of 1275 psi Note that this projection assumes a nominal corrosion rate, even though spot inspections performed in 1994 and again in April 2010 showed that coating was intact and in good condition. Corrosion rate for sound coated carbon steel piping is zero.

Coating Life Span Proper preparation of the carbon steel piping and apt of the coating will ensure proper adherence to the piping. The recent inspections performed on 4/22/2010 of piping buried since construction showed that the coating was intact and in good condition, and the piping showed no indication of degradation or corrosion. Theirfore, the coating is assumed to remain intact until next Unit 2 refueling outa ge.

In-service testing ,"

The latest in-serice testing for Unit 2 punmps and valves are provided below. Results of all testing was SAT.,

Procedur#e, Compoonent 2' TWork Order Date Results 2 _.OP-SO.~AF!0005 /21 & 22 Motor Driven Pumps 50114298 11/5/2009 SAT S'2,P-SO.AF-0006 AF23 Sto5 Check Valves 50128109 01/24/2010 SAT LS2.OP:SVAF 0007 13Turbine Driven Pump 50113100 10/13/20091 SAT Conclusion Uufonsildering 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 ard .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 ($2R1 8).

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OP-AA-1 08-115 Revision 3 ATTACHMENT I 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 inspections 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 functi(s) of the SSC. As a minimum the following should be addressed

  • as applicable, in describing the SSC safety or safety support function(s):

UFSAR Section 10.4.7.2: Auxiliary Feedwater The AFW System serves as a backup system for supplying feedwater to secondary side of the steam generators at times when the Main Feedwater System is not available. The AFW System is relied upon to prevent core damage and system overpressurization in the'event of accidents such as a loss of normal feedwater or a secondary"system pipe rupture, and to provide a means for plant cooldown.

Each unit is equipped with one turbine-driven and two motor-driven auxiliary feed pumps. Each motor-driven pump discharges to two steam generators with a normally isolated (21 and22AF923 valves) cross-connect line joining the motor-driven pump discharge headers. The turbine-driven pump feeds all four steam generators.

Feedwater flow is controlled from the Control Room by remotely operated flow control valves in the supply linefs to each steam generator. In order to prevent a runout condition of the motor drivenpumps 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 the design bases analyses, 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\TLO1\Local Settings\Temporary Internet Files\Content.Outlook\HDZV6AOE\OP EVAL 10-005 Salem U2 Buried AFW Pine.docc

OP-AA-1 08-115 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 fromth*e auxiliary feed storage tank. A safety grade, automatic low pressure trip is provided 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 deminerdlizec water storage tanks (500,000 gallons capacity each), the two fire protection and domestic water storage tanks (350,000 gallons'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 istherefore intendedfor use only in the event of emergency situations. \: \

  • Does the SSC receive/initiatean RPS or ESF'actuation signal?

YES. The Auxiliary Feedwater System (AFWS) is an Engineered Safeguards System (ESF). The motor driven auxiliary Feedwater pumps (MDAFPs) start automatically due to (1) trip of both main Feedwater pumps (LONF), (2) Safety Injection signal, and (3) a Low-Low signalfrom anyone S.G. The two MDAFPs are loaded onto the emergency diesel generators by the automatic loadsequencer. The turbine driven auxiliary Feedwa;te purp (T)AP, starts automatically on (1) a Low-Low level in two of the four SGs, (2) Loss of 125VD* control power, (3) Loss of Control Air, and (4) undervoltage

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\TLO1\Local Settings\Temporary Internet Files\Content.Outlook\HDZV6AOE\OP EVAL 10-005 Salem U2 Buried AFW Pioe.docc

OP-AA-1 08-115 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:

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 lvelIs 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 (RCP'B)integrity.

  • 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 cooldown the reactor. The AFWS does not affect the rod control system or the alternative boron chemical shim system that control reactivity in the core. By providing the SG secondary side heat sink medium capable of receiving heat transfer from the reactor coolant system, the AFWS has an indirect positive reactivity effect bycooling and thus increasing the density of the reactor coolant neuirdn moderator.... ...

Maintain the reactor in a safe shutdown condition?

YES. The licensing basis for safe shutdown at Salem is hot standby (HSB). The AFWS must perform its 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) to allow 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 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 incapacitates AFST, DWSTs, and FPWSTs. During normal

'cooldown, each of~the MVDAFPs has the capacity to remove heat from the SGs at a sufficient rate to prevent RCS overpressurization and to maintain SG levels to prevent thermal cycling.

a Prevent or mitigate the consequences of an accident that could result in offsite exposures comparable to 10 CFR 50.34(a)(1), 10 CFR 50.67(b)(2), or 10 CFR 100.11 guidelines, as applicable.

YES. The AFWS performs a safety function in mitigating design basis accidents, including LOOP, LONF, FWLB, MVSLB, SGTR, and small break LOCA (SBLOCA) by supplying adequate feedwater to the secondary side of the Steam Generators to prevent overheating the reactor coolant system and to provide a means for achieving plant cooldown to initiation of the residual heat removal system. Depending on the design basis accident, the AFWS either maintains or limits feedwater to the SGs. For C:\Documents and Settings\TLO1\Local Settings\Temporary Internet Files\Content.Outlook\HDZV6AOE\OP EVAL 10-005 Salem U2 Buried AFW Pitre.docc

OP-AA-1 08-115 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 isolation 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 bey o mitigate a design basis event?

NO. The AFW pumps canhe operated manually at their local control panel or from the main Control/Room. Automatic initiation signals are designed to prevent system malfunction given a single failure. AFW flow is controlled from the Control Room using remotelype rated flow control valves (AF2l's) in the supply lines to each SG. Safety-related flow irndication toeach SG is prov!ded in the Control Room. The flow control valves have reduced capacity trim to limit the maximum flow under certain plant conditions. /

all1Have specified safety functions described in TS been included?

YES. Salem TSs 'require that at least three independent AFW pumps, their associated manual activation switches in the Control Room, and their flow paths are operable in Modes I 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).

  • Haveall 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 degraded or nonconforming condition on the SSC safety function(s); (b) any requirements or commitments established for the SSC and any challenges to these; (c) hte circumstances of the degraded/nonconforming condition, including the possible failure mechanism(s);

(d) whether the potential failure is time dependent an 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 ight of other open OpEvals:

Table: List of Existing OpEvals.

ENTERY ,*= Z;;=WNRSAU EXPECTED NUMBER NOTFIORDER E DESCRIPTION OWNER STATUS CLOSURE DATE CLOSURE 80094618-issued, SI/2 ECCS roo*m need orders07-033 80094618 9/07/07 cooler thermstats0 Bhardn planned 08/11 (DCP 80094618 and 80095613- issued, 80095613) , need orders Motorp e S/S2 On-Line DCP 08-040 70R87831 8/08/08 Vave - degraded Ciarlante 80099509 to be 12/23/10 V dere voltagl

- e e planned, scheduled, voltage-\:*,

...... installed 09-09 60084229 4/01/09 CAAI4/CAA17V7/CAA20 Hassler Perform Inspections 5/31/10 09-019 66085180 8/10/09 SRW watertight door Hassle Replace door seal 5/21/10

__._-____VWW 0022 09-021 70103767 11/5/09 Can Liner Curran Repair in S2R18 S2R18

')PZR Heater busses E Procure new panel 09-023 70104221 11/9/09 &G 3 R. Smith door design/ 6/1/10 Soverheating design new Implement 10-001 70106347 1/28/10 21 SI pump oil leak Hummel Develop repair plan 9/27/10 Repair Oil Leak 10-002 6089385 03/19/10 #4 SW Bay Ventilation Hayman Perform repairs 4/27/10

  • '03/19/10 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 controller for 1SIV3 Hayman Perform repairs 9/30/10 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 1 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 identified active leak reported.

B) ANY REQUIREMENTS OR COMMITMENTS ESTABLISHED FOR THE SSC AND ANY CHALLENGES TO THESE 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/NONCONFORM ING CONDITION, INCLUDING THE POSSIBLE FAILURE MECHANISM(S)-

The degradation of the auxiliary feed water piping at Unit 2 is substantially less than that at Unit 1. Based on the existing data, it is concluded that the AFW piping will be able to perform its intended design function 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 TIM1E DEPENDENT AND WHETHER THE CONDITION WILL CONTINUE TO DEGRADE AND/OR Wý44 THE POTENTIAL CONSEQUENCES INCREASE; AND The potentialfailure of the 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 per year until the pipe will no longer be capable of supporting the maximum crredible operating pressure without margin to eminent failure.

E)THE AGGREGATE EFFECT OF THE DEGRADED OR NONCONFORMING CONDITION IN LIGHT OF" OTHER OPEN OPEVALS (SEE TABLE OF OPEN OPEVALS ABOVE)

The aggregate impact of the 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]

engineering judgment, etc.):

Summary SIA Finite Element Analysis Report The preliminary analysis of the Salem Unit I underground auxiliary feedwater piping is complete. The analysis evaluated the region specified in S-TODI-2010-0005 which C:\Documents and Settings\TLOl\Local Settings\Temporary Internet Files\Content.Outlook\HDZV6AOE\OP EVAL 10-005 Salem U2 Buried AFW Pioe.docc

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.

/

YES NO 2.4 Are compensatory measures and/or corrective actions required? X X If 2.4 = YES, complete section 3.0 (if NO N/A section 3.0).

Reference Documents:

2.4.1. Technical Specifications Section(s):

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

3.7.3.9 3.9.4: Inservice Testing Pumps and Valvest 10.4.7.2, Auxiliary Feedwat*

. System! "

15.2.8, Loss of Normal Feedwater 15.2.9, Loss of Offsite Power to Station Auxiliaries (LOP) 15.3.1, Loss of Reactor'Coolant from Small Ruptured Pipes (SBLOCA) 15.4.1, Major Reactor CoolantSystem Pipe Ruptures (LBLOCA) 15.4.2, Major Secondary System Pipe Rupture (MSLB) 154.3, Major Rupture of Main Feedwater Line (FWLB) 15.4.4, Steam Generator Tube Rupture (SGTR)

2.4.3. Other

Technical Evaluation 70108698, Rev. 0 Technical Evaluation20459941 Potential Water Sources Inner Mechanical Penetration ANSI31.1, 1967 Ed., Power Piping DWG 205336 Sheet'I Rev. 49 -

DWG 218233 Sheet I Rev. 11 S-C-MPOO-MGS-0001, SP$54, 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\TLO1\Local Settings\Temporary Internet Files\Content.Outlook\HDZV6AOE\OP EVAL 10-005 Salem U2 Buried AFW PiDe.docc

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-T i-2'0-10-0005 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 and NDE-R007 (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 function(s) in the TS and the intention is to continue operating the plant in that condition, then recordbeelow, as appropriate, any required compensatory measures to support operability*rd/or corrective actions required to restore full qualification. For corrective actions, documn"t when the actions should be completed (e.g., immediate, within next13 week period, next outage, etc.)

and the basis for timeliness of the action. Corrective action imeframes longer than the next refueling outage are to be explicitly justified as art of the OpEval or deficiency tracking documentation being used to perform the corrective action.

\i!1 =* ,: :I

/, .... ..

Compensatory Measure #1: None Responsibleý Dept./Siipv.:

Action Due:

Action Tracking #:

Compensatory Measure #2: None Responsible Dept./Supv.: /

Action Due:

Action Tracking #:

C:\Documents and Settings\TLO1\Local Settings\Temporary Internet Files\Content.Outlook\HDZV6AOE\OP EVAL 10-005 Salem U2 Buried AFW Pioe.docc

OP-AA-108-115 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 inspections to determine pipe minimum as-found wall thicknesses. Replace if necessary, alnon-conforming buried AFW piping. Work Order 60084161 is created to perform this task.

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

Action Tracking #: Work Order 60084161 Corrective Action #2:

Responsible Dept./Supv.:

Action Due:

Basis for timeliness of action:

Action Tracking #:

4. SIGNATURES:

4.1 IPreparer(s) Mark Puher K Date 04/22/2010 Robert Down Date 04/22/2010 4.2 Reviewer KiraanMathur Date 04/22/2010 (I 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\TLO1\Local Settings\Temporary Internet Files\Content.Outlook\HDZV6AOE\OP EVAL 10-005 Salem U2 Buried AFW Piie.docc

OP-AA-1 08-115 Revision 3 ATTACHMENT 1 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 ).

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 Management Approval Date 5.3 Ensure the completed form is forwarded to the OEPM fnr processing, Action Tracking entry, and cancellation of any open compensatory measures, as appropriate.

C:\Documents and Settings\TLO1\Local Settings\Temporary Internet Files\Content.Outlook\HDZV6AOE\OP EVAL 10-005 Salem U2 Buried AFW Pioe.docc

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