IR 05000344/1988025

Insp Rept 50-344/88-25 on 880516-31.No Violations Noted. Major Areas Inspected:Licensee Activities in Resolving Reactor Plant Pipe Whip Restraint Design Vs as-built Gap Discrepancies & Inservice Insp Ultrasonic Test Activities

ML20150B021
Person / Time
Site:	Trojan File:Portland General Electric icon.png
Issue date:	06/16/1988
From:	Ang W, Chaffee A NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
To:
Shared Package
ML20150B020	List: IR 05000344/1988025 ML20150B016
References
50-344-88-25, NUDOCS 8807110216
Download: ML20150B021 (17)

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U. S. N'JCLEAR REGULATORY COMMISSION

REGION V

Report N /88-25 Docket N License N NPF-1 Licensee: Portland General Electric Company 121 S. W. Salmon Street Portland, Oregon Facility Name: Trojan Nuclear Plant Inspection at: Rainier, Oregon; Portland, Oregon; and Rockville, MD Inspection conducted: May 16-31, 1988 Inspectors: b g 4 ~/'* M W. P. An , Reactdr Inspector Date Signed Approved by: /bE / d-l6-Bf A.~ E. ChWifee,- Deputy Director, Division of Date Signed Reactor Safety and Projects Summary:

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Inspection on May 16-31, 1988 (Report 50-344/88-251 Areas Inspected: Special, announced inspection of the Trojan Nuclear Power Plan The inspection focused on licensee activities in resolving reactor plant pipe whip restraint design versus as-built gap discrepancies, pressurizer surge line deflections and inservice inspection ultrasonic test activitie Inspection procedures 30703, 92700 and 73051 were used during this inspectio L

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8807110216 880617 PDR ADOCK 05000344 Q PDC

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P DETAILS Persons Contacted Portland General Electric

• • *D. Cockfield, Vice-President, Nuclear C. Olmstead, Trojan Plant General Manager

• • *L. Erickson, Manager, Nuclear QA Department (Acting)

• A. Roller, Manager, Nuclear Plant Engineering

• • *T. Walt, Manager, Nuclear Safety and Regulation

• • *M. Hoffman, Manager, Mechanical Engineering Branch

• G. Zimmerman, Manager, Nuclear Regulation Branch G. Kent, Surveillance and Test Supervising Engineer

• R. Wehage, Supervising Mechanical Engineer M. Schwartz, Manager, Surveillance and Test Engineering Branch D. Williams, QC NDE Level III Examiner Licensee Consultants / Contractors

• • W. Bak, Engineering Division Manager, Impell

• • L. Memula, Plant Design Chief Engineer, Bechtel

• • D. H. Roarty, Senior Engineer, Westinghouse

• • B. F. Mauren, Senior Engineer, Westhinghouse R. McClain, NDE Level III Examiner, Townsend and Bottum N. Bollingmo, NDE Level-III Examiner, Townsend and Bottum _

W. Shelton, NDE Level III Examinar, Townsend and Bottum NRC

• • G. Hollahan, Assistant Director, Regions III and V, Division of Projects,NRR

• • G. Knighton, Director, Region V Plants, Division of. Projects, NRR

• • T. Marsh, Chief, Mechanical Engineering Branch, NRR

• • P. T. Kuo, Section Chief, Mechanical Engineering Branch, NRR

• • T. Chan, Trojan Project Manager, Division of Projects, NRR -

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• • S. Hou, Senior Mechanical Engir.eer, Division of Engineering, NRR

• • G. DeGrassi, NRC Consultant, Brookhaven National Laboratory l

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NRC Resident Inspector G. Suh, Resident Inspector State of Oregon H. Mooney, Oregon Department of Energy In addition to the individuals identified above, various other engineering, quality assurance, maintenance, and operations personnel and other members of the licensee's staff were contacted by the team and attended the team exit meetin * Attended Exit Meeting on May 24, 198 ** Attended PGE-NRC Meeting on May 31, 198 . Onsite Follow-up of Written Reports of Non Routine Ever.ts at Power Reactor Facilities (92700)

Pipe Whip Rectraint Discrepancies and Unusual Pipe Movement of Pressurizer Surge Line Concerns regarding safety-related pipe supports during the 1987 refueling outage resulted in the licensee's initiating a large Bore Pipe Support Design Verification Program. The verification program included an evaluation of the adequacy of Pipe Whip Restraint (WR) designs. The evaluation of the WR designs determined that gaps specified in the original WR design differed, and in some case conflicted with, thermal and seismic pipe movements predicted by piping analysis for the corresponding piping. Consequently, the licensee perfucmed field measurements of 142 WR to pipe gaps to evaluate the as-built /as-found conditions with new calculations. The subsequent field measurements, calculations and evaluations identified: (1) discrepancies in the design / construction of WR's in general and (2) WR contact and unexpected deflections of the pressurizer surge lin Discrepancies in the Design / Construction of WR Of the 142 WRs whose gaps were measured and compared with piping analysis thermal and seismic pipe movements, the licensee determined l

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79 WRs had sufficient gaps to preclude restricted pipe movemen WRs were already in contact with the associated piping while the plant was in a cold shutdown condition. Pipe movement was

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restricted land unanalyzed loads could potentially be imposed on the piping at the contact location: during normal operating conditions thennal movements) or during potential design conditions seismic movements).

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47.WR had measured gaps that were less than.the aaximum pipe movements. predicted by the piping thermal and seismic analysis;

- i.e. piping movement could be restricted by the WR and unanalyzed loads could potentially be imposed on the: piping at the contact locations during conditions analyzed fo *

8 WRs were associated with the pressurizer surge line and will be discussed reparately in paragraph 2.8 of this inspection repor The field measurement of the WR to pipe gaps was performed by Nuclear Plant Engineering (NPE) Department rather than the Quality Assurance / Quality Control Departme..t. The NRC inspectors questioned the validity of non-QC measurements for acceptance of the 79 WRs that were considered to be acceptable as-is. The licensee agreed to perform sampling QC inspections of the 79 WRs to confirm the engineering gap measurement Based on the discrepancies identified by the licensee between WR design gaps and analytical piping thermal and seismic movements, the licensee and its contractors (Impell, Bechtel and Westinghouse) were performing technical specification (TS) operability evaluations on tha piping that had been identified to be in contact with WR's and for the piping whose WR to pipe gaps indicated that it could have come in contact due to actual previous operating experience. At the time of the NRC inspaction, the plant was in Mode 5 - Cold Shutdown and no WR conditions had baen identified by the licensee to have resulted in any piping or systems being considered inoperable for Mode 5. The licensee stated that it would assure future TS operability for the applicable operating modes, prior to entry into those moden, by either analysis or, if required, modification of piping or WRs. The results of the piping analysis will be provided to NRR for review and con. men Thelicensee'sArchitect-Engineers (A/E)wasperformingcalculations to detennine structural adequacy of WRs and to determine future adequacy of the WR to pipe gaps. At the time of the inspection, 53 WRs had been identified that required re-shimming to allow unrestricted thermal and seismic pipe movements through those WR NRR and Region V inspectors selected the following WRs whose evaluations had been completed for further review:

5.4 - Residual Heat Removal System 14.3 - Safety Injection System 17.5 - Pressurizer Spray Line 21.1 - Boron Injection System

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The licensee provided copies of the WR calculations / evaluation to NRR for review and comment. Region V inspectors, with the assistance of the licensee's QC inspectors, inspncted the four WR' The inspectors noted that one of the four NRC/QC gap mea- lrements for WR 14.3 was measured to be approximately 0.200 inch smaller than the NPE measurement. The NRC inspectors reviewed maintenance request 88-3629 for WR 14.3 and determined that only gaps that were being modified would be inspected by QC. The apparently discrepant gap measurement was not being modified and consequently was not required to be reinspected. The NRC inspectors questioned the apparent lack of inspection for all gaps of a WR that was being modified since potentially all gaps could be changed during the modification. The licensee committed to perform QC inspections of all gaps for WR's that are being modified /re-shimmed. The licensee evaluated the noted discrepancy in gap measurements for WR 14.3 and determined that the revised gap was still acceptable. At the end of the inspection period, the licensee was evaluating the possibility of providing greater tolerance for gap measurements to alleviate potential minor gap measurement discrepancie The WR calculations / evaluations for the four WR's, noted above were discussed with the licensee. The NRC inspectors noted that the licensee's NPE organization was performing an oversight function for the results of the A/E's work but had not perfomed a detailed review of the A/E's methodology for the calculations, For axample, the accuracy of the Lotus Spreadsheet Program being used by the A/E for evaluation of pipe deflections at the WR's had not been verified by the licensee. Also, the use of a linear relationship between the WR ductility and the pipe to WR gap had not been verified by the licensee. During the inspection period the licensee verbally reported that analysis for alternate charging system piping going through WR 18.1 showed the piping exceeding design limits and fatigue analysis showed it good for only 2 cycles (the plant had experienced approximately 32 cycles already). However, further review by the licensee revealed that an error in transpocition of gap measurements to the calculation was the cause of the reported calculation results. As a result of the noted error, the licensee committed to perform a 100% QA review of the WR calculations / evaluation The licensee intends to perform visual inspection of WR to pipe gaps for selected WRs during hot standby conditions when the plaiit heats up. In addition the licensee has committed to inspect spring cans and snubbers adjacent to selected wA's to determine if actual pipe taermal movements correspond with che piping thermal analysis. The licensee's inspection program was discussed by the licensee with NRR repretentatives from the Mechanical Engineering Branch during a meeting at Rockville, MD on May 3;, 1988. NRR suggested the additional use of "scratch pads" to provide a more complete measurement of pipe movements during the various thermal cycles the plant will experience while operating. The licensee agreed to consider the use of "scratch pads".

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On May 31, 1988, the licensee submitted to the NRC its report on its

"Pipe Whip Restraint and Pressurizer Surge Line Investigation". The report attributed the root cause of the inadequate gaps in 55 of the 134 pipe WR's to be:

Failure to reconcile the A-E determined WR gaps with the final piping analyse *

Failure to provide adequate allowance for seismic induced movements when determining gap siz *

Incorrect gaps set during constructio *

Gap change due to thermal shakedown of piping syste *

The gap settings for WRs had not been inspected or monitored since 197 During the May 31, 1988 Licensee meeting with NRR and Region V at Rockville, MD, the licensee's A/E stated that Bechtel was evaluating the need for a potential 10 CFR Part 21 report to the NRC in relation to the inadequate WR gap B. Pressurizer Surge Line Movement As noted in paragraph 2.A above, WR inspections performed during the 1988 outage found a surge line WR (1,2) in contact with the piping (see attached figure 1 for WR locations). The licensee removed WR 1.2 shims to determine how much contact existed. During this process, the piping was measured to have a 4771 pound uplift force on WR 1.2 and, following removal of the shims, the pipe moved upward an additional 3/8 inch. The piping had been previously observed to have a 7/16 inch clearance between WR 1.2 and the top of the pipe in June of 198 The May 31, 1988 PGE report on Pipe Whip Restraint and Pressurizer Surge Line Investigation provided the following additional history relevant to the surge lin "PGE began monitoring the pressurizer surge line in 1982

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following removal of the pressurizer surge line thermal sleeve I from the reactor coolant loop nozzl Thermal sleeve removal was required because the sleeve welds had failed. The NSSS Vendor demonstrated by a revised fatigue analysis that the sleeve was not necessary to protect the reactor coolant loop nozzle from thermal transient effect To remove the thermal sleeve, the surge line was cut at two locations: adjacent to the reactor coolant loop at the

. nozzle-to-surge line weld and at a second point several feet

) away toward the pressurizer beyond a 45-degree bend. Once this l section of piping had been removed, the thermal sleeve was extracted and the line welded back in plac PGE was advised l

at that time that some amount of thermal shakedown (ie, l

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permanent deformation of the pipe as a result of relaxation of internal stresses) could be expected, and therefore, it was necessary for the line to be observed and, if needed, adjustments made at the hangers and at the pipe WR The surge line WRs were monitored over the next six cutage Contact was noted between the surge line and some of its WRs each year through the 1986 refueling outag For each contact, a root cause was postulated and an evaluation of the piping system was performed. In all cases, the piping system and its restraints were shown to satisfy the design limits. A description of the surge line and WR history from 1982 to the present is provided in Table 5.3."

Table 5.3 is attached to this inspection repor LER 85-16 revision 2, dated December 1, 1986, provided detsils on binding of steam generators and restricted Reactor Coolant Loop (RCL) movemen The NRC inspectors visually inspected the surge line from the RCL"B" hot leg to WR 1.8 and visually inspected the remainder of the surge line up to the pressurizer from an elevation approximately level with the horizontal run of the surge lin A permanent set on the surge line was not readily apparent by visual inspectio However, the inspectors noted that the surge line to WR 1.4 gap was almost nonexisten The inspectors also noted that Spring Hanger (SH) 2 appeared to be topped out high above the hot condition setting for the spring can (the plant was in cold shutdown). The observed conditions indicated that some plastic deformation of the surge line had occurre (1) Root Cause Analysis The Licensee ovaluation of the noted condition of the surge line included an evaluation of the following potential root causes for the problem:

Thermal shakedown following the removal of the thermal sleeve in 1982 was a possible cause. However, the plant had already gone through several heatup and cooldown cycles and shakedown should have occurred in one or two cycles. The licensee therefore felt that shakedown was no

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longer a facto *

Design and construction errors of the surge line whip restraints was a possible cause. Surge line WR gaps had been monitored and reset regularly over the past six years. This therefore was not considered the cause of the proble *

Abnormal movement of the RCL or the pressurizer was a i possible cause. RCL motion has been monitored since 1986 l and indicates that after 1986 the RCL moved as expected t and is not the cause of the surge line problem.

I Inspections of the pressurizer indicates it is moving as

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Thermal stratification of water in the surge lin The licensee reported the following in its May 31, 1988 "Pipe Whip Restraint and Pressurizer Surge Line Investigation Report":

"Thermal Stratification of Water in the Surge Line Thernal stratification has previously been identified in

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the Trojan surge line, However, during evaluation of this effect, the surge line motion was not explained. A 100*F differential temperature (which was assumed at that time)

across the line was not adequate to explain the movemen '

Also, the RCL restrained thermal growth was identified during this time (see above), and further evaluation of stratified flow was discontinue Industry experience since 1987 had indicated that significant thermal stratification in the pressurizer surge line is possibl Preliminary thermal-hydraulic calculations confirm this for typical flow rates in the surge line. Piping stress analysis modeling stratified flow has been performed which shows significantly more deflection than'obtained from analysis assuming uniform temperatur This deflection increases with increasing differential temperature between the top and bottom of the pipe, The evaluation indicates that the line under stratifiad conditions would deflect downward, contact WRs 1.2 and 1.4, and undergo plastic deformation which would result in the cold set of the pipe above its original location. This agrees with the observed vertical set of the line at these locations in the cold conditio Operating conditions which produce stratification occur during heatup, cooldown, and steady-state operation of the plan The 1985 assessment of thermal stratification had focused on hot standby and power operation during which there was a lower temperature difference because these were considered to be the limiting conditions at that

, time. Current efforts have focu.ad on plant conditions

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during heatup when the temperature differences between the i RCL and pressurizer are larger.

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During a typical plant heatup, water in the pressurizer is heated to a temperature of approximately 440", thermal expansion of the water occurs, and a bubble is formed in the pressurizer. Loop temperature is gradually increasin As the water flows from the pressurizer to the loop (out-surge), the hotter water rides on a layer of cooler water, causing the upper part of the pipe to be heated to a higher temperature than the lower part of the

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u . 8 pipe...... The potential differential temperature could be as high as 300*F,. based upon plant operating limitations."

The licensee's root cause evaluation was discussed with the licensee. .PGE contracted Impe11 Corporation to perform a nonlinear piping analysis to confirm the' thermal stratification hypothesis. WR gaps were included in the nonlinear analysis and the surge-line was evaluated for several complete heat-up and cooldown cycles. The licensee state'l that the analysis showed that surge line movement closed the gaps on several whip restraints, and resulted in pipe deflections that correlated with the actual observed condition of the line -- an upward set in the cold condition. The licensee submitted a copy of the Impell , Analysis to NRR fr,r review and commen (2) Operability Analysis

.The licensee was performing an operability analysis of the surge line by contracting with Impell to perform an elastic piping stress analysis, and with Westinghouse to perform a fatigue analysis. The results of the analysis was discussed with the lice se The licensee considered the surge line to be operable due to the fatigue analysis results which showed the line good for 40 heat-up and cooldown cycles versus an actual total of 32 cycles having been experienced by the lin The licensee submitted the results of the above noted analyses to NRR for review and commen (3) Corrective Action _s i In addition to the analyses noted above, PGE performed the following more immediate corrective actions:

• Ultrasonic (UT) and liquid penetrant (PT) examinations of all pressurizer surge line circumferential welds from the RCS nozzle-to pipe weld to the pressurizer nozzle-to pipe wel * All pressurizer surge line WR gaps were measure * A visual inspection of the surge line revealed no visible distress to the piping.

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• The pressurizer surge line WRs and hangers were visually l

inspected and no structural damage was found.

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! * The Reactor Coolant Loop Thermal Expansion Program results ( were reviewed to confirm proper movement of the RCL. In l addition, visual inspections were performed on the the steam generator seismic restraints and upper support ring No abnormal conditions were found.

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The pressurizer anchor bolts and seismic supports were checked. No abnormal conditions were foun The licensee's corrective actions were discussed by the licensee with NRR and Region V in a meeting at Rockville, MD on May 31, 1988. The NRC representatives informed the licensee that it should also consider performance of UT on the base materi.', in addition to the welds, in the highly stressed areas determined by piping analysis. The licensee agreed to consider the additional UT examination At the end of this inspection period, the licensee was in the process of evaluating potentially significant indications (approximately 40 percent through wall from the inside diameter, approximately 200 degrees around) on two welds adjacent to WR 1.8. The licensee committed to resolve the noted condition prior to heatu The licensee's A-E was evaluating the WR gaps and was still in the process of determining the corrective actions necessary for the WRs. Studies were being performed regarding the necessary gaps, WR structural capabilities, effect of some pipe contact with one or more WRs and possibility of removal of one or more WR No conclusions had been reached at the end of this inspection period. The licensee had committed to resolve the condition, as necessary, to justify operability of the surge line prior to heat-u The licensee committed to perform a surge line temperature monitoring program to further confirm the occurrence of thermal stratification and more precisely define the surge line movenents through various thermal cycles, including the period when a bubble is drawn in the pressurizer. Discussions with the licensee indicated that minimal consideration was being given to potential effects of pressurizer movement on the surge lin The NRC inspectors informed the licensee that although its evaluations of pressurizer movement appeared to be reasonable, the monitoring program should confirm that

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evaluation by actual measurements. The licensee's surge line monitoring program was discussed by the licensee with NRR and j, Region V on May 31, 1988 at Rockville, MD. The licensee committed to include displacement monitors that would confirm normal pressurizer movements being reflected on the surge line (4) Management Involvement During the inspection and various licensee meetings regarding WR and surge line movement, intimate involvement by the PGE Vice President, Nuclear, the Nuclear Plant Engineering Manager

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and the Manager of Nuclear Safety and Regulation was evident.

I In addition, the licensee formed a Senior Review Committee (SRC) to provide oversight of the activities associated with WR gaps and pressurizer surge line movemen The committee consisted of the following: ,

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_ . 10 A, N. Roller (Chairman) Manager, Nuclear Plant Engineering /

Nuclear Division / Portland General Electric Company L. W. Erickson Manager, Nuclear Quality Assurance /

Nuclear Division, Portland General Electric Company L. Memula, P Chief Plant Design Engineer /Bechtel, San Francisco W. L. Bak Manager, Engineering Mechanics Division /Impell Corporation D. H. Roarty Senior Mechanical Engineering /

Westinghouse The SRC provided oversight to the WR and pressurizer surge line evaluation and resolution activitie By its report attached to the licensee's May 31, 1988 "Pipe Whip Restraint and Pressurizer Surge Line Investigation" report, the SRC concurred with the licensee's evaluations and corrective action The NRC inspectors concluded that PGE management involvement in the WR gap and pressur!zer surge line movement issue was comprehensive and in-dept (5) QA/QC Involvement The initial lack of QA/QC involvement in the measurement of as-found gaps for the WR appeared to the NRC inspectors to be less than adequate. However, subsequent discussions with the licensee noted that QA had performed several audits of engineering activities including the RCL monitoring progra During the inspection the licensee performed QC sampling measurements of WR gaps as noted in paragraph 2.A above. In addition, during the inspection increased involvement by the QA Manager in the WR and pressurizer surge line movement activities was evident and inclusion in the SRC was note Finally, licensee commitment to perform QC inspections of all WR gaps on all modified WRs and the QA audit of A-E calculations provided further indication of increasing QA/QC involvemen The NRC inspectors concluded that QA/QC t

involvement would be adequate, if sustained as describe Additional involvement could be considered for audits of NPE, Impell, Westinghouse. QA/QC involvement in the WR monitiring program and pressurizer surge line monitoring program would also enhance the quality of the progra (6) PGE "Pipe Whip Rjstraint and Pressurizer Surae Line Investigation" Ryport On May 31, 1988 the licensee met with NRR and Region V at Rockville, MD to submit and discuss the subject repor As

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previously noted, NRR was still in the process of reviewing the report and various supporting analyses. Preliminary information indicated that PGE evaluations and corrective actions, including the added cortnitments noted in the foregoing portions of this inspection report, appeared to be reasonabl Various aspects of the program were still in proces Additional NRC Region V inspection by the Trojan Resident Inspector staff and, as appropriate, Regional Staff, will be performed as part of the routine progra Westinghouse representatives attended the May 31, 1988 meeting between PGE, NRR and Region V. During that meeting, Westinghouse representatives stated that Westinghouse was evaluating the need for a potential 10 CFR Part 21 report regarding thermal stratificatio No violations or deviations were identifie . Allegation RV-88-A-0027 Characterization (1) Ultrasonic testing was not performed in accordance with ASME Section XI Articles 111-4430 and III-3230(d). Specifically, these sections of the code require use of 1/2 V methods and Trojar. is not using this method for applicable inspection activitie (2) Nondestructive examination was not performed in accordance with the ASME Section XI Table IWB-2500-1 Item B8.20. Specifically, measurements of the pressurizer skirt weld should have included volumetric examination in addition to the surface method use Implied Significance to Design, Construction or Operation Mondestructive Examinations (NDE) including Ultrasonic Testing (UT)

not performed in accordance with the ASME Boiler and Pressure Vessel (B and PV) Code may not detect defects in welds and may lead to subsequent failure of the weld Assessment of Safety Significance On May 25, 1988, Region V informed PGE by letter that the first concern was brought to our attention by their Quality Hotline and the second concern came up during subsequent follow-up. The letter confirmed that FGE was evaluating the concerns and would orovide Region V with the results of its evaluation In the interim, an onsite inspection was performed to review the licensee's UT procedures and UT calibration methods. By letter dated November 14, 1986, PGE submitted its second 10-year Interval i Inservice Program. The letter states that the program is based on

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the 1983 ASME B and PV Code including the sunner 1983 addeada. The licensee submittal was still being reviewcd by NRR.

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During the inspection,-the inspector witnessed the performance of a UT calibration for a surge line wel The calibration was performed to demonstrate the procedure, equipment and calibration block used by the licensee's contracto The procedure used was Townsend and Bottum Services procedure QAP-UT-101 revision 0 change 1, Ultrasonic Butt Welds. The procedure utilizes A 1 vee calibration and examination method. The inspector discussed the procedure and the ASME B and PV Code Requirements (Section XI Article III-4430 and III-3230(d) with the PGE surveillance and Test Engineering Manager, the PGE level III QC Examiner and three Townsend and Bottum Level III Examiners. The licensee stated that 1 vee calibration provides at least equal sensitivity as the vee calibration required by ASME Section XI Article III-3230(d) and demonstrated this to the NRC inspecto In addition, the licensee stated that the 1 vee examination encompasses the vee examination required by ASME Section XI Article III-4430 On June 7, 1988,.the licensee responded to the Region V letter regarding the subject NDE concerns. The licensee stated that based on their evaluation and consultation with Level III Examiners of four different companies, consultation with the chairman of the volumetric inspection working group of the ASME Section XI subcommittee, the UT examinations being performed at Trojan meet ASME Section XI requirement In addition, the licensee stated that it would further confirm this evaluation by requesting a code interpretation from ASM The June 7,1988 PGE letter also provided an evaluation of the concern regarding volumetric examination of the pressurizer skirt weld. The letter notes that ASME XI Table IWB-2500-1 Item B8.20 requires volumetric or surface examination, as applicable but does not require both. During this outage, the licensee chose to perform surface examination of side A-B but was unable to perform surface examination of side C-D due to high radiation levels. The licensee has rescheduled this examinations for the 1989 refueling outage, which they considered would oe the end of the first period of the second ten year inservice inspection interva A+ that time, they would have to decide on either completing the surface examinations or performing volumetric examination or submitting a relief request to the NRC in accordance with 10 CFR 50.55 During the discussions with the licensee, the NRC inspector noted that the only PGE UT Level III examiner in the Nuclear Organization was in the QA/QC organization. It was further noted that the licensee consulted with numerous Level III examiners outside the compan, but did not consult with the QC Level III Examiner regarding this problem. The inspector informed the licensee of the following statement from SNT-TC-1B paragraph 4.3.c:

" NDT LEVEL III - An HDT Level III individual shall be capable of and responsibic for establishing techniques;

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interpreting code, standards and specifications; and designating the particular test method and technique to be used. He shall be responsible for the complete NDT

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s operation he is qua'lified for and assigned to, and shall be capable of evaluating results in terms of existing codes, standards,'and specifications...."

.The licensee acknowledged the apparent weakness in their program

.regarding involvement-of their own level III Examiner.- Staff Position

'Th'e results of thelinspection and the licensee' June 7, 1988 letter were discussed with reviewers from the Materials Branch of NRR. The staff

. concluded that:the licensee.had-performed an acceptable evaluation of the noted concerns. The staff further agreed that a code interpretation regarding_Section XI Article 111-4430 would further confirm the licensee's positio No violations or deviations were identifie . Exit Interview

'- The inspection scope and findings were summarized on May 24, 1988 with those persons indicated in paragraph I above. The inspectors-described the areas inspected and discussed in detail the inspection findings. In addition a meeting between PGE and the NRC_was held at Rockville, MD on May 31, 1988. Attendees of that meeting are indicated in Paragraph No violations or deviations were identifie ,

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FI G URE 1 PRESSURIZER SURGE LINE (14")

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TABLE Page 1 of 2

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PRESSURIZER SURCE LINE AND PIPE WHIP RESTRAINT HISTORY Restraints Date Contacted Action Taken Postulated Root Cause Observations Comments 05/82 N/A Surge line nozzle N/A N/A N/A thermal liner remove ?lpe cut and rowelde /82 Analyzed stresse Thennel shakedow Top of pipe had Evaluation indicated no contacted W proble /83 1.2, Restraints reshimmed: Thermal shakedown N/A 1.2 - moved 17/32 i due to rewelding of from top to botto surge line after .

1.4 - moved 3/4 in, removal of thermal fec.a top to botto line /84 Restraint reshimmed: Thet nal sha'aedown N/A 1/4 in. shim remove due to rewelding of 5 surge line after removal of thersel line /85 1.1, Thermal AT = 100*F hot Analysis indicated that stratificatio standb thermal stratification AT = 50*F pow could not cause observed pipe movement. Analysis ,

of as-found condition j indicated piping within

design stress limits.

j Indication of potential

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RCL movement was identified based upon observed condition of hot leg whip rettraint and on steam generator snubber result .,_ . - _ - ._ _ _ .__ _ _ _

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TABLE Pago 2 cf 2

PRESSURIZER SURCE LINE AND PIPE WHIP RESTRAINT HISTORE Restraints D*te Contacted Action Taken Postulated Root Cause Observations Comments 05/86 Restore restraint Reactor Coolant Thermal growth of Analysis indicated surge clamp. Prepare for Loop B hot leg hot leg was restrained line would not move as replacement in 198 motion at surge- by inadequate gaps on observed. Analysis of line nozzl steam generator, as-found condition showed surge line within acceptable stress limits. The monitoring program to measure RCL motion at the steam generator supports and hot les

,

whip restraint was l

initiated.

05/87 Restraint clamp E/A N/A N/A ,.

O'

replaced as planne KL/36920