IR 05000254/1986019

Insp Repts 50-254/86-19 & 50-265/86-14 on 861104-870115.No Violations or Deviations Identified.Major Areas Inspected: Inservice Insp Activities,Review of Program,Procedures & Licensee Action on IE Bulletins

ML20215E463
Person / Time
Site:	Quad Cities
Issue date:	01/30/1987
From:	Danielson D, Ward D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20215E459	List: IR 05000254/1986019 ML20215E455
References
FRN-59FR979 50-254-86-19-01, 50-254-86-19-1, 50-265-86-14, AC93-1-033, AC93-1-33, IEB-79-14, IEB-80-07, IEB-80-7, IEB-83-02, IEB-83-2, NUDOCS 8706190380
Download: ML20215E463 (12)

Text

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f U. S. NUCLEAR REGULATORY.. COMMISSION-

REGION III

Reports No. 50-254/86019(DRS); 50-265/86014(DRS)

'. Docket Nos.- 50-254;-50-265 Licenses No. DPR-29; DPR-30 Licensee: Commonwe'alth Edison Company P. O. Box-767 Chicago, IL .60690

. Facility Name: Quad Cities Station, Units 1 and 2 Inspection At: Quad Cities Site, Cordova, Illinois Inspection Conducted: November 4-5, 12-13, 18, 26, December 3-4,-10-11, 6, and January 7-8, 15, 1987 Inspector: . D. Ward 30/f 7

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Date b [An~

! Accompanied By: D. F. Danielson kud7 Date (December 3-4)

Approved By:

W hk D. H. Danielson, Chief M3e F7 Materials and Processes Section-

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Date Inspection Summary

Inspection on November 4-5, 12-13, 18, 26, December 3-4, 10-11, 17-18, 1986,'

and January 7-8, lb, 198/ (Report No. 50-254/86019(DRS); No. 50-26b/86014(URS))

-Areas Inspected: Routine, unannounced inspection of inservice inspection (ISI) activities,includingreviewofprogram(73051), procedures (73052),

observation of work and work activities (73753), and data review and evaluation H (73755); licensee action on IE' Bulletins (92703) and licensee event reports (92700); ultrasonic examination (UT) of shroud head bolts (57080); radiographic ,

examination (RT)ofbatteryjumpercables(57090);modificationofstandby i liquid control system (37701, 55700, 57700); and thickness checks performed on l the drywell (57080).  !

.Results: No violations or deviations were identifie j i

i 8706190380 870130 );

PDR ADDCK 05000254 G PDR l

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. 1'. Persons Contacted ~

Commonwealth Edison Company (Ceco)

• D. Gibson, Quality Assurance'(QA) Superintendent

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'*R. Robey, Services:Su~perintendent  !

• C.-' Smith,. Quality. Control (QC) Supervisor <

• M.'Kool, Regulatory Assurance Supervisor

'*J. Hoeller, Lead Nuclear Engineer

• H. Do. ISI/IST Group Leader

R. Bax,' Sr. Station Manager D. Thayer, Maintenance Senior Staff Engineer C. Kron1ch, Technical Staff Engineer K. Medulan, ISI Coordinator B. Wilson, level III, ND J. Ford, QC' Inspector

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Structural Integrity Associates, In ..

D. Pitcairn, Associate General Electric.(GE)

R. Hooper, Manager, Inspection Services-T. Brinkman, Supervisor Morrison Construction-Company,(MCC)

W. Flesch, QC Supervisor Hartford Steam Boiler-Inspection & Insurance Company (HSB)

F. Roose, ANII United States Nuclear Regulatory Commission (NRC)

D. Danielson, Chief, Materials and Processes Section A. Morrongi_ello, Resident Inspector The inspector also contacted and interviewed other licensee and contractor employee * Denotes those present at the final exit interview January 15, 198 . Licensee Action on IE Bulletins (Closed)-IE Bulletin No. 83-02 (254/83-02-BB): Stress corrosion cracking in large diameter stainless steep recirculation system l

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. pipin The inspector reviewed the fina1Lresponse, followed the activities and considers-the' bulletin close Reference: NRC Inspection Reports No.- 50-254/84-06,No.'50-265/(84-05,-

No. 50-254/85016, No. 50-265/85008). (Close'd)IEBulletinNo. 80-07(254/80-07-BB;265/80-07-BB):

Ultrasonicexamination(UT)ofUnit2JetPumfBeamBolt Assemblies._ All 20 jet pump beams were UT'd )y CECO October 20, 1986, and found to be acceptabl It'is' CECO'sintentto'continuetoUT'the~jetpumpbeamsduringeach refueling outage. Any cracked beams will be replaced prior to unit startup. The NRC inspector. reviewed the procedure utilized to UT thejetpumpbeamsandotherassociateddocumentationanddetermined that the actions implemented by.the licensee meet the intent of the

' Bulleti . Licensee Action on Licensee Event Reports (LER) (Closed) LER No.86-017, Revision 00: . Weld No. 02K-S3 pinhole leak: Weld No. 02K-53 1s an elbow to aipe, 12" diameter, schedule 80, stainless steel weld in tie recirculation syste Manual UT was performed on the weld in 1983, and no recordable indications were'found. On November 5, 1986, while CECO'was'

conducting a visual examination of the prepared weld surface prior to UT, a small pinhole with water seeping from it was discovere Manual UT determined the leak to be an axially-oriented crack aaproximately'0.4" long at 2 o' clock on the elbow side of the wel T1e weld was then weld overlayed, UT'd and found to be acceptabl (Closed) LER No.86-024, Revision 00: Residual heat removal (RHR)

service water (RHRSW) supports exceed Code stress allowables. On August 11, 1986, CECO found that there were supports on the RHR service water system that would experience uplift loads or exceed the AISC Code allowable stresses during safe shutdown earthquake (SSE) loading. The hangers that exceeded the allowable stresse were supports on the original piping. During the engineering phase oftheproject,severalsupportswereidentifiedthathadthe ,

potential for requiring modifications. However, it was later '

determinedduringtheprojectclosecutthatthesupportshadnot i been modified as required. Cause of the omission was attributed to inadequate design control by Ceco's engineering and the architect engineer, CYGN Modification M-4-1/2-86-19 was initiated to modify the necessary RHRSW supports and to bring the RHRSW to within the '

design specifications of the FSAR for long-term operation. The NRC inspector visually examined the final modification of supports M-10260-127, 145, 700, 701 and 702 and reviewed procedures, specifications, drawings and other documentation related to the modifications. The NRC inspector found the modification and l documentation acceptable and considers this item close (0 pen) LER 86-025, Revision 00: Torus attached small bore piping does not meet code allowable limits due to design error, During a re-analysis of the IE Bulletin No. 79-14 Mark I Program, it was

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discoveredthatcertainsmallboretorusattachedpiping.(four-inches-or less) did not meet FSAR: requirements to meet Code-allowable stress limits for seismic and Mark I loading condition , The architect engineer performed an operability. assessment and determined that all lines in question were operable. 'Approximately

20 to 30 hangers per unit will require modification. Design of the modification supports was'in progress during this outage. This

, modification may start in late 198 .(Closed) LER No.86-033, Revision 00: Control-Room Panel Mounting ~;

Units-1 and 2. In late March 1986 unanchored control room panels were discovered at Dresden by CECO. As a result a walkdown by CECO of the Quad Cities.' control room panels was performed on March 27, 1986. The purpose of this~walkdown was.to verify whether the> lack of intentional positive anchorage found at Dresden was the case at Quad Cities.. Like Dresden,.the bolted connections. indicated on the design document (4E-1161) between the floor anchored base channel and the panels did not exist. Discrepancy Record (DR) 04-86-2451 was initiated-to document this discrepanc Unlike Dresden, which had no lositive intentional anchorage, the Quad Cities panels were attacled to the anchored floor channels-with a combination of plug and fillet weld CECO aerformed an-operability assessment on April 1, 198 The opera)ility assessment usingengineeringjudgementconcludedthatthereexistedsufficient positive anchorage to withstand significant seismic motio The recent dual unit outage allowed access into the control room-panel Sargent and Lundy (S&L) engineers were contracted to evaluate the control room panel mounting. A detailed'walkdown to record the existing positive panel anchorage was performed. An evaluation of the anchorages indicated that.the anchorage of some of the panels were not quite within allowable stresses based upon FSAR requirement Safety-related Modification No. M-4-1-86-36 was initiated to bring the control room panel anchorages within FSAR seismic requirement Workwas'completedundersafety-relatedWorkRequestNo.Q5327 'On November 13, 1986, Sargent & Lundy issued five en ineering change notices (ECN),QC-865-19throughQC-865-23. The ECN s showed the information required to bring all the panel anchorages within FSAR allowable The NRC inspector visually examined the following:

• Fillet welds that were welded by Morrison Construction Company which attached the outside of Panels 901-2, 901-10, 901-11, 901-13, 901-19 and 901-37 to the channel bas * Four brace supports that were added to attach the top of *

severalpanelstotheadjacentconcretewal * Braces that were added to panels 912-2, 912-8, and 912- y- ;

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These re) airs / modifications were completed on November 15,'1986, when bot 1 units were in cold shutdow ..

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lThe NRC' inspector reviewed the following documents: -QC Surveillance; DR;; Work' Request package 53275; Welders Certifications in Accordance

--with.ASME Section IX; Wel ing Procedure Specifications; Five- ..

. Engineering Change Notices (ECN);' Drawings; Operability: Assessment;

" Weld Data Reports; Process Control ~ Checklist; Traveller Checklist; .

Station Modifications Checklist; Final Documentation Checklist; Work-Request Checklis In addition, S&L performed an operability. assessment of the as-found'

i state of the control-room panel anchorage. The purpose of this assessment was to investigate whether the panels would have been stable in case of a safe shutdown earthcuake (SSE) in the originally constructed

, condition. S&L concludec that even though the as-found anchorages did not always meet the FSAR requirements, the panels would have

remained. stable during an SS

The NRC inspector found the repairs / modifications and documentation-acceptable and considers;this item clos . Inservice Inspection (ISI) Unit 2

- General This is the eighth outage of the first period of the second ten year pla CECO, GE and Conam performed the ISI in accordance with ASME Section XI, 1980 Edition, Winter 1980 addenda and Code Case N-23 CECO performed. visual examinations (VT), GE performed ultrasonic (UT), magnetic particle (MT), and liquid penetrant examinations :

(PT), and Conam performed PT on the weld overlays onl The Level II and"III UT personnel performing UT were qualified at the EPRI NDE center after September 10 1985 by successfully performing the practical examination. Level i perso,nnel not cualified at EPRI who were performing UT scanning duties were trainec by EPRI cualified personnel onsite. Ceco's Level III UT personnel who reviewec^GE's NDE results were also EPRI qualifie In performing ultrasonic examinations on the welds, GE used their ;

data acquisition system (SMART) that is a complete UT package capable of examining welds by remote control and storing the collected-data for future review / evaluation. The display is a color presentation that is stored on a floppy disk for future referenc Normally the system uses the standard shear wave transducer for flaw detection and sizing; however, other types of transducers may be used with the system as desire The UT of weld overlays was performed to a CECO procedure based on i techniques developed by EPRI.' The EPRI techniques for examination of weld overlays utilize duel element, pitch catch, and focused refracted "L" wave transducers. For the overlay weld metal,

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0 ~ the primary examination was performed using 70 : transducers, q supplemented _with 00 creeping wave transducers at the option of ,

the examiner.- Base metal-under the overlay was examined using 60 ' '

transducers. The examinations were made-in two' directions for both -

circumferentially and axially. oriented-. flaw l

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During<the outage, a chemical' decontamination of the reactor recirculation and reactor water clean-up (RWCU) systems took

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n place. London Nuclear Systems supplied the equipment and chemicals, operated the decontamination equipment, and provided chemistry support. Chem-nuclear systems provided'the mobile solidification services.. The process involved the injection of low oxidation state metal ion (LOMI) decontamination solvent circulating through the piping, removing the activated corrosion layer from the internal surfaces of the system. The activated corrosion products in solution-were removed from the piping with mixed bed resins.- The spent-

. resins were slurried to a mobile cement solidification system for preparation and shipment. The NRC inspector reviewed procedures, program, drawings, and other related documentatio A total of.127 IGSCC susceptible welds were UT'd during this outage compared to'64 welds called for in the inspection plan. The

following table provides a summary of the proposed inspection plan

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and the number of welds that were actually UT d.during this outag QUAD CITIES UNIT No. 2 84-11 AUGMENTED INSPECTION PLAN T

1- Total 84-11 Weld Total Total Overlays Welds System Size Total Sample Examined Examined-Recirculation Risers 12" 44 14 10 44 SE (Thermal 12" 10 2 Sleeve) 2 Header 22" 22 6 2 22 Outlets 28" 30 15 6 30 LPCI 16" 32 6 6 SDC- 20" 18 4 2 5 CS 10" 27 5 5 HS/RWCU 6" 13 3 4 Recirc/CRD HS/HV 4" 35 7 7 JPI 10 2 2 TOTAL- 241 64 20 127 l

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Column 3 - TOTAL STAINLESS STEEL WELDS SUSCEPTIBLE TI IGSCC ON A PARTICULAR' SYSTEM OR SIZ .

i 4 - GENERIC LETTER 84-11 1986 TOTAL SAMPLE ON ORIGINAL. INSPECTION PLA I

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5 - FOURTEEN ORIGINAL OVERLAYS PLUS SIX NEW ONE A TOTAL OF 127 WELDS INCLUDING THE EXPANDED SAMPL The total of 20 weld overlays examined includes the 14 listed in the plan and six new overlay The previous. overlays were upgraded to full structural design thickness and the new overlays were applied to the full structural design criteri Each of the overlays was surface finished to permit application of EPRI techniques for overlay i U The overlay weld metal and the upper 25% of the original piping !

' material were UT' Nineteen weld overlays had sound weld metal of

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sufficient thickness to meet the design criteria. One weld overlay (weld 02A-S10) was found to have axial indications in the overlay such that the full structural design criteria were not me Ten welds previously reported as containing IGSCC flaw indications were UT'd this outage. All of these welds were treated by induction heating stress improvement (IHSI) in 1983 and have previously been shown to be acceptable based on flawed pipe analyses. Of these welds, two (both end caps) showed the presence of axial flaws and were weld :

overlay repaire The following new welds were found to require a weld overlay:

• Weld No. 02K-S3, elbow-to pipe, 12" diameter, schedule 80, stainless steel, recirculation system;

• ' Weld No. 02K-S4, pipe-to-elbow,12" diameter, schedule 80, stainless steel, recirculation syste * Weld No. 02B-59, pipe to end cap, 22" diameter, schedule 80, stainless steel, recirculation syste * Weld No. 02C-S3, elbow-to pipe , 12" diameter, schedule 80, stainless steel, recirculation syste * Weld No. 02BS-F2, safe end to elbow, 28" diameter, 1.115" thick, stainless steel, recirculation syste * Weld No. 02A-S10, pipe to end cap, 22" diameter, schedule 80, stainless steel, recirculation system: Manual UT was performed on this weld in 1983 and 1985, and the results were 360 intermittent circumfrential cracks on the cap side of the weld that were all acceptable. The manual UT and the GE Ultra Image Automatic Scanner (SMART) UT system were used this outage and detected nine separate circulation cracks totaling 8.6" in length with a maximum thru wall depth of 26%. Approximately 29 axial cracks were detected with a maximum thru wall depth of 30%; all cracks begin on the cap sid .. .

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, 97 After a full, structural; weld overlay was made and surface conditioned, a post weld overlay UT was. performed. This UT revealed several axial flaw. indications, eight of which had a remaining ligament equal to

.or -less than the minimum weld overlay design thickness. The minimum remaining ligament measure was 0.28". These flaws were associated with steam blow out repairs during the weld overlay, application. In

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addition, a 2" long circumferential1y oriented flaw indication was

observed at a remaining ligament (depth from outside surface of weld overlay) of 0.42". . UT of this specific area by a Ceco UT Level III determined that this: indication was a circumferential crack associated with'two axial indication CECO' elected to add an additional layer of weld metal. The intent wi.s to increase.the remaining ligament over all flaws of greater than the full structural overlay design thickness. Low heat input ard bead overlay parameters were utilized with the intent of minimizing flaw

.of..the welding. UT propagation due after measurements to the thehigh strains additional and layer temperatures showed a weld metal thickness of 0.48" on the cap side compared to the previous-0.42". Both manual and automated UT data were collected on the remaining ligaments over the' flaws. Manual and-automated UT were made of the entire circumference or the cap side of the weld. 'The results of the GE SMART image system generally paralleled the manual UT results. The automated UT found one circumferential and eight axial flaws to be present in the weld overlay meta A comparison of the manual and automated UT. data for the flaws with the shortest ligaments of sound metal is as-follows:

Manual- Automated Circumferential 0.24"-0.32" 0.38" Axial 0.3" -0.4" 0.35"

-Axial 0.24"-0.28" 0.36" Axial 0.26 "0.30" 0.44" The manual UT data sheet stated that the weld was very noisy around the cracked areas and difficult to U The flaws with the least remaining ligaments were in locations where steam blowouts. occurred during overlay welding and localized weld repair In a conversation with personnel of the EPRI NDE center, GE and j CECO's Technical Center, it was stated that the expected crack i sizing tolerance between examinations was approximately 0.1".

It was agreed that the comparisons of manual and automated data discussed were within expectations for independent examination The weld overlay design thickness of 0.38" was based on nominal j

pipingwallthicknessandincludedaconservativelycalculated 0.030 or crack growth by fatigue over a 30 year lifetime for the 1 circumferential fla A revised design thickness was calculated by CECO based on the minimum wall thickness of 0.979" and elimination of the fatigue crack growth allowance. The new design thickness for {

the overlay on Weld No. 02A-$10 is 0.33".

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/CECohasconsideredbothsetsofUTdatainevaluatingtheremaining ligament of the flaws. The mean of the manual UT, data when averaged ,

'with the automated, provides a remaining ligament of 0.33" for the .>

circumferential flaw. The three deep'est axial flaws have average remaining ligaments of 0.31" to 0.36 . On'this basis, the short' I-circumferential flaw meets the full structural overlay, design

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thickness. The deepest axial flaw is marginally less than the design'

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thickness for a circumferential flaw, but significantly exceeds the 1 requirements for a leakage barrier overlay for axial flaws. An ASME

! 'Section XI evaluation in accordance with Paragra)h No. IWB-3642 was performed by CECO for the minimum ligaments of tie manual sizing and acceptance of the flaws for an' operating cycle was' demonstrate CECO requested and received permission from NRR to operate Quad Cities Unit 2 for one operating cycle with end cap Weld No. 02A-S10 in the as-is condition described abov CECO stated that Unit 2 will continue to adhere to the restricted leakage detection and leakage limits contained in Generic Letter No. 84-11 for the upcoming operating cycle. Plant shutdown shall be initiated for inspection and corrective action when any leakage system indicates, within any period of two hours, an increase in rate of unidentified leakage in excess of 2GPM. The sump level shall be monitored at four-hour intervals or les Weld No. 02BD-F8, valve to elbow, 28" diameter, schedule 80,

--stainless steel weld in the recirculation system, was found to'

have a circumferential crack intermittent 12" with a combined length of approximately 4.5" and a 15% maximum thru wall depth.

l This weld was found not to require a weld overlay by NUTECH.

b The UT was expanded in accordance with Paragra)h No. IWB-2430 of the ASME Code Section XI for that system and size 3ecause of the defect The company performing the actual welding was GAPC The welding filler metal used was Type ER308L for the weld overlays. All welding was performed in accordance with welding procedure specifications written and qualified in accordance with ASME Section IX, the latest addition of the Code. The preparation, I

application, and examination of the weld overlays were described in the station travelers and procedures for the wor Programs and Procedures The NRC inspector. reviewed the ISI procedures and programs and found them to be acceptable. Where these rules were determined to be impractical, specific relief was requested in writing. The NRC inspector reviewed the specific relief requests including the related correspondence between the licensee and the NR Review of Material, Equipment and Personnel Certifications, Audits and Data The NRC inspector reviewed the following documents:

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• Data reports this outage and las * Ultrasonic instruments, calibration blocks, transducers and ;

couplant certification l

• Liquid penetrant, cleaner and developer material * Magnetic particle., materials and equipment

• NDE personnel certifications in accordance with SNT-TC-1 * Audits and surveillance * Records or welder and welding operator qualification * Certified material test reports for the filler materia Observation of Work Activities The NRC inspector observed work and had discussions with personnel during the ISI activitie These observations included calibration, performance of the following NDE and documentation:

• Welding of recirculation system welds No. 02E-F6A, No. 02AS-S4, No. 02BD-S6, No. 02BS-53, No. 02AS-59, No. 02A-S10, No. 02K-54, No._02C-S3, No. 02BS-F2 and 02B-5 * UT of thermal sleeve Welds No. 02K-F1, No. 02J-S * Welding of RHR Weld No. 105-F * UT of core spray Weld No. 14A-S1,

• UT of recirculation Weld No. 02AD-F * PT safe end to nozzle Weld No. 14A-S1 Each overlay was liquid penetrant examined (PT) which included the base metal one inch of each end of the overlay. UT was performed in accordance with CECO procedures to establish the soundness of the weld overlay and its fusion to the base meta No violations or deviations were identifie . Ultrasonic Examining (UT) Shroud Head Bolts General Electric (GE) submitted an information letter to CECO that stated cracking, of shroud head bolts (SHB) had been observed at four BWR/4's and one BWR/3. The letter also stated the following, in part: the cracking occurs in the NICRFE alloy 600 shaft of the SHB in a crevices region formed by a 304 $/S sleeve welded to the bolt shaft. Complete failure was observed at one plant. Cracking at other plants was found by ultrasonic examinations (UT). After receiving the letter, CECO

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n contracted GE to perform UT on 48 bolts for evidence of cracking. The NRC inspector reviewed procedures, personnel certifications and other related documentation including UT reports that indicated there were no indications of cracking detecte i No violations or deviations were identifie !

7. Battery Jumper' Cable Unit 1 & 2  ;

I The battery jumper cables for the Units 1 and 2 125 volt and 250 volt '

station batterles were examined by radiography to determine the i penetration of the cable into the lug. The NRC insoector reviewed

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radiographs in which the radiography was performed using CECO's special process procedure NDT-A, Revision 11, for guidance. Penetrameters were not used therefore the radiographs were for information only. Four cables were found unacceptable as a result of the radiography. The cables were provided by Gould National Batteries on Ceco's Purchase Order No. 30566 No violations or deviations were identific . Standby Liquid Control System Modification The modification was made to allow simultaneous operation of the standby licuid control system (SLCS) injection pumps and increase the minimum-socium pentaborate solution concentration to 14 weiglyt percent. The NRC inspector observed a portion of the modification activities, reviewed radiographs, NRC-NRR Generic Letter No. 85-06, Quality Assurance Guidance for ATWS equipment, final modification design package, Procedure No. Q.6, ' l Revision 13, and other-related documentatio No violations or deviations were identifie . Thickness Checks Performed on Unit 1 and 2 Drywell Shells Due to a problem of drywell steel liner deterioration at Oyster Creek Nuclear Station, CECO decided to have a Level II from Conam Inspection perform thickness measurements on the drywell liner plate. The thickness l was measured in eight locations on Unit 2 coinciding with each vent header penetration using a thickness measuring instrument. The UT for the eight readings was performed at aaproximately 2" above the concrete basement floor directly under eac1 penetration. The average readings ranged from 1.24" to 1.27". The original shell thickness was, by design, required to be nominally 11/8" thic(. Each location was checked in three to four spots to achieve the average. Being there is a reinforcing plate on the outside of the shell at these locations that could possibly isolate the plate from the outside shell environment, Ceco decided to reconduct the inspection (removing the paint for UT) at the midpoint between the vent headers at the floor concrete level in eight more locations. The plate material was not isolated from the outside shell environment and there were no external plates in this area. The results ranged from 1.61" through 1.226"; this was over the nominal 1.125" design

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header The'results ranged from 1.210" t .220" penetration X-5E thick which was and X-5 acceptabl In Unit ~1 an ultrasonic instrument was used to perform the eight thickness !

measurements thru the paint at the midpoint between the vent headers at.- 1 the floor concrete level.as Unit 2. The results ranged from-approximatel .20" to 1.30'.'; this was within nominal design requirement !

Ceco's conclusion is that this inspection confirmed that there doesn't-appear to be any thinning degradation on the drywell shells at this 1 tim No violations or deviations were identifie ~1 Exit Interview The inspector met with site. representatives (denoted in Persons Contacted paragraph)attheconclusionoftheinspectio The inspector summarized the scope and findings of the inspection noted in this report. The .

inspector also discussed the likely informational content of the I inspection report with regard to documents or processes reviewed by.the inspection during the inspection. The licensee did not identify any such ;

documents / processes as proprietar '

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