IR 05000254/1998021
| ML20207G209 | |
| Person / Time | |
|---|---|
| Site: | Quad Cities  |
| Issue date: | 03/05/1999 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML20207G165 | List: |
| References | |
| 50-254-98-21, 50-265-98-21, NUDOCS 9903120017 | |
| Download: ML20207G209 (18) | |
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U.S. NUCLEAR REGULATORY COMMISSICN REGION lli Docket Nos: 50-254;50-265 License Nos: DPR-29; DPR-30 Report Nos: 50-254/98021(DRS); 50-265/98021(DRS)
Licensee: Commonwealth Edison Company Facility: Quad Cities Nuclear Power Station, Units 1 and 2 Location: 22710 206th Avenue North Cordova, IL 61242 Dates: November 12 through December 18,1998 Inspectors: K. S. GreenBates l NRC Reactor Engineer l
l L.S. Sage lilinois Department of Nuclear Safety (IDNS)
Approved by: J. A. Gavula, Chief, Engineering Specialists Branch 1 Division of Reactor Safety l
l 9903120017 990305 PDR ADOCK 05000254 0 PDR l
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EXECUTIVE SUMMARY Quad Cities Nuclear Power Station, Units 1 & 2 NRC Inspection Reports 50-254/98021; 50-265/98021 This was a routine ir'spection that focused on the conduct of inservice inspection activities at Quad Cites during refueling outage 15. The inspection also reviewed the overall ISI Program Plan for both Unit 1 and Unit 2. The following specific observations were made:
Maintenance e Inservice inspection activities for Unit 1's refueling outage 15 were adequately I implemented and properly performed. However, the identification of additional i intergranular stress corrosion cracking in recirculation system piping provided further !
evidence that previous induction heat stress improvement efforts were ineffectiv (Section M1.1)
e Lack of uniformity and sufficient detail in the documentation of previous examinations hampered efforts to determine crack growth. Examination efforts from RF014 failed to characterize the full extent of flaws in two recirculation system welds. (Section M1)
e The inspectors concluded that the Unit 1 RF015 activities reviewed for the main steam and reactor vessel internal inservice inspections were implemented in an effective manner and that contract NDE activities were properly performed in accordance with the applicable ASME orindustry standard requirements. The inspectors also concluded that the licensee had implemented the appropriate actions to mitigate the consequences of a cracked Jet pump riser brace by training control room operators and implementing additional surveillances. The licensee demonstrated a good safety focus by limiting core flow during operation to minimize the growth rate of existing jet pump crack (Section M1.2 and M1.3)
e The ISI NDE procedures reviewed by the inspectors, were found to be in accordance with the ASME Code requirements. The inspectors observed three examples where-ancillary plant procedural guidance did not fully support ISI Program activitie (Section M3.1) 1 I
e A violation pertaining to the failure to request Code relief for multiple Unit 1 and Unit 2 I weld examinations with limited coverage was identified. Timeliness of corrective actions for this issue, originally identified in 1997, was considered poor in general, the informal and poorly controlled relief request process contributed to several ISI Program related problems. (Section M4.1)
e The personnel performing the NDE during RF015 inspections were found to have proper qualifications, which had been reviewed by the licensee staff and the ANil (Section M5.1)
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- Aggressive self-assessments of the ISI function effectively identified a number of issue Implementation of corrective actions were slow, resulting in a significant amount of work yet to be accomplished. (Section M6.1)
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Report Details Quad Cities is currently in their third ten year inservice inspection (ISI) interval. The interval began on February 18,1993, for Unit 1 and March 10,1993, for Unit 2. Both Units are committed to ASME Section XI,1989 Edition with several relief request exceptions. Additionally, other regulatory requirements and commitments such as Generic Letter (GL) 88-01 "NRC Position on IGSCC [intergranular stress corrosion cracking] in BWR Austenitic Stainless Steel Pipina" apply. The inspection was conducted during the Unit 1 refueling cutage (RFO) 15 which is the second of three period examinations planned for the third ten year ISI interva Historically, Unit 1 has had a multitude of IGSCC cracking problem II. Maintenance M1 Conduct of Maintenance M1.1 Recirculation System inservice inspection Inspection Scooe (73753. 73755)
The inspectors reviewed activities regarding the surface and volumetric inspection of the Unit i recirculation system pipin Observations and Findinas inspectors observed that dye penetrant and ultrasonic examinations (UT) were performed on recirculation system piping under ISI and GL 88-01 guidelines. Analysis of the non-destructive examination (NDE) data was conducted by contract personne When contract personnel identified a relevant indication, a Comed Level lli staff member then performed a supplemental independent examinatio During RFO15, seven 28-inch recirculation system welds were identified with indication The indications were located within weldments which previously had an induction heat stress improvement (IHSI) process applied and were originally designated as GL 88-01 Category C type welds. Three of the seven flaws had been initially found during RFO14 examinations and had been evaluated and left in service without repair. The four new indications exceeded the allowable flaw sizes of IWB-3500 in Section XI of the 1989 American Society of Mechanical Engineers (ASME) Code, and thereiore did not meet the criteria for continued operation without evaluation. The inspectors observed that Comed appropriately initiated engineering fracture analysis evaluations and that flaw evaluations were performed in accordance with the methodology and acceptance criteria specified in subarticle IWB-3640 of Section XI, ASME Code,1989 Edition. The continued identification of new IGSCC flaws in welds previously treated with IHSI provided further evidence that the IHSI efforts for Unit 1 were ineffectiv The licensee performed a design modification to repair three of the new flaws, and one pre-existing flaw found during RFO14. The modification consisted of four weld overlays, each in accordance with ASME Code Case N-504, " Alternative Rules for Repair of
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l Class 1,2 and 3 Austenitic Stainless Steel Piping,Section XI, Division 1." The remaining three welds with identified indications were evaluated and left in service without repai j The inspectors noted that two of the we!- ;verlayed during this outage appeared to exhibit unprecedented crack growth. Weld 02BS-F14 had indications dispositioned in RFO14 as 22 inches long with a maximum depth of 0.401 inches, compared to the RFO15 disposition of 45.5 inches long with a maximum depth of 0.83 inches ;
(approximately 60 percent through wall). Weld 02AS-F9 had indications dispositioned l as root geometry during RFO14, and as a 360 degree circumferential intermittent flaw, j 0.25 inches deep during RFO15. These differences were outside the bounds of previous )
Quad Cities crack growth evaluations. The licensee subsequently determined that weld
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root geometry had masked the true extent of the flaws during the RFO14 examinatio During evaluation of the potential crack growth rate concern, the licensee stated that a l I
comparison of RFO14/RFO15 NDE results was hampered due to a lack of detailin records of the UT examinations. Sufficient documentation of the indications in welds 02BS-F14 and 02AS-F9 had not been recorded to determine specific changes in j recirculation system crack growth. Past UT inspections were performed manually, by !
different vendors, and the quality of inservice inspection records was not uniform and lacked sufficient detail from which to draw detailed conclusions about changes in the size of the flaw. To correct this problem in the future, Comed revised the goveming procedure to improve the detail and consistency of manual UT exam record-keeping. In addition, Comed stated that they intended to use the automated UT method wherever possible to perform recirculation inspections. However, the inspector observed that the licensee did not apply or evaluate the use of the automated UT method for the three recirculation cracks left in service after RFO15. This appeared to be inconsistent with the intent to improve examination record .
In addition, the inspectors observed that, in response to the NRC's previous concerns .
regarding the effectiveness of the Unit 1 IHSI process, the licensee had revised the inspection frequency from GL 88-01 Category C to Category D. However, after finding a flaw in the initial sample of IHSI welds and expanding the sample to include 100 percent of the remaining IHSI welds, the inspectors noted that all of the Category C welds would require examination under the guidance of GL 88-01. After discussion of this matter with NRR staff, the inspectors did not cortsider this specific issue to be a technical concern at this time, however, justification for this deviation from the generic letter guidance was not documented nor had been discussed with NR c. Conclusjo_gs inservice inspection activities during the Unit 1 RF015 were effectively implemented and properly performed. However, the identification of additionalintergranular stress corrosion cracking in recirculation system piping provided further evidence that previous induction heat stress improvement efforts were ineffectiv . . _. _ . _ _ _ __ _ _ . _ _ . _ _ . _ . _ . _ . _ _ _ _ _ _ _ _ . . _ _ _ _ _ _ . . _
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A Lack of uniformity and sufficient detail in the documentation of previous ISI examinations hampered efforts to determine crack growth. Examination efforts from RFO14 failed to characterize the full extent of flaws in two recirculation system weld M1.2 Intemal Reactor Vessel Examinations Inspection Scooe (73753. 73052)
NDE contract personnel and licensee staff were interviewed by the inspectors conceming examinations of the Unit 1 core spray piping and jet pumps.' Visual examinations (VT) and UT analysis / disposition records of identified indications were also reviewe Observations and Findinas The inspectors observed that core spray piping examinations identified one new flaw in a reactor pressure vessel (RPV) core spray downcomer piping weld. The new flaw was at a location similar to two pre-existing flaws which were also re-examined. The inspectors observed that the RFO15 namination results characterized the two pre-existing core spray flaws at a significantly smaller length than prior inspections. . Review indicated that this apparent reduction in crack size was most likely due to the refined sizing available with the automated UT technique used in RFO15, versus the visual and pole mounted UT used in past inspections. The licensee determined that the apparent cause of the ,
three flaws was IGSCC, and that they were acceptable as per a bounding analysis j performed nuring RFO14. Inspectors observed that core spray reactor vessel intemal '
inspections were implemented in an effective manner using state of the art equipment, I and that contract NDE activities were properly performed in accordance with the I applicable industry standard requirement ;
The inspectors observed that the reactor vessel intemal inspections identified the following jet pump cracks: l
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. Jet Pump 7/8 - Four crack indications were found on the riser pipe The cracks l started at the weld connection of the riser brace yoke to the pipe and grew vertically / diagonally away from the weld and into the basemetal of the pip . Jet Pump 19/20 - Three IGSCC type crack indications were found on the riser pipe. The cracks were located at the RS-1 elbow to the thermal sleeve weld on the elbow side of the wel Inspectors observed that the RFO15 activities reviewed for the jet pump vessel internal inspections were implemented in an effective manner and that contract NDE activities -
were properly performed in accordano, with the applicable industry standard requirements. The inspectors observed that jet pump 7/8 cracking appeared to Se somewhat atypical of IGSCC cracking as it had propagated into the basemetal, and that the licensee's evaluation appeared to appropriately disposition these cracks as a l
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combination of IGSCC initiated cracking in the heat affected zone of the brace weld and fatigue due to flow induced vibratio The in-depth evaluation required to determine crack growth rates, could not be completed prior to the scheduled start-up and the vendor (General Electric (GE)), was requested to perform a safety assessmelt to support intene onaration of Unit 1. The GE analyses concluded that there was n1t a safety concern to preclude start-up and normal plant operation for an eight week time period. Since jet pump riser vibration is proportional to pump flow, the licensee lim?ted core flow to 95 oercent to minimize the growth rate of existing cracks. Additionally, control room operators were trained to recognize and appropriately respond to signvicant changes in c'ack size and increased l monitoring was institute l Subsequent GE quantitative evaluation determined that jet pump 7/8 repairs should be performed prior to the next U1 outage. The inspectors verified that the licensee had scheduled a repair within the time constraints of the evaluatio '
M Main Steam ISI Examinations i Insoection Scope (73753. 73755) !
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Inspectors obssrved the following main steam system and reactor head NDE 1 examinations performed by contract personnel. The inspectors had discussions with personnel during the activity and observed activities regarding broad scope licensee oversight and flaw evaluatio * Ultrasonic examination of Unit 1 Main Steam pipe-to-valve weldment 30A-F3 . Ultrasonic examination of Unit 1 Main Steam pipe-to-valve weldment 32-F1 Ultrasonic examination of Unit 1 Reactor Head nozzle to safe end dissimilar metal weldment N6A-S Observations and Findinas The inspectors observed, that the contract personnel performing the NDE appeared knowledgeable of NDE procedural requirements and were proficient in the performance of the UT method. UT indications recorded on the data sheets were evaluated using additional UT examinationr, with different transducers, construction radiographs, or bot Allindications reviewed appeared to be appropriately dispositioned and indications identified during the NDE examinations were within ASME Code requirements, or were repaired. The inspectors also observed that the NDE data packages had been properly reviewe __ _ _ __ . __ . __ _ _ _ _ - _ -_ __
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i I Conclusions on Main Steam and Reactor Vessel Internal Inspections The inspectors concluded that the Unit 1 RFO15 activities reviewed for the main steam and reactor vessel internal inservice inspections were implemented in an effective ,
manner and that contract NDE activities were properly performed in accordance with the l l applicable ASME or industry standard requirements. The inspectors also concluded that
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the licensee had implemented the appropriate actions to mitigate the consequences of a l cracked jet pipe riser brace by training control room operators and implementing I
additional surveillances. The licensee demonstrated a good safety focus by limiting core flow during operation to minimize the growth rate of existing jet pump crack M3 Maintenance Procedures and Documentation M3.1 Procedural Control of ISI Activities i l Inspection Scope (73753. 73052)
The inspectors reviewed the procedural controls to conduct ISI program activitie !
Seven procedures and other applicab!e quality assurance documentation related to the performance and documentation of the ISI activities were reviewe Observations and Findinas The inspectors observed that the !SI NDE procedures reviewed were approved by the Authorized Nuclear Inservice Inspector (ANil), Corporate NDE Level Ill, and Comed management. Many of the Comed procedures used at Quad Cities were the same as those used at other Comed plants. The NDE procedures reviewed were found to be in accordance with the 1989 ASME Code Section V and XI requirements. Revisions and addenda to procedures were reviewed and approved in the same manner as the original procedure Although the SI NDE procedures reviewed by the inspectors appt .o adequately control ISI NDE activities, the inspectors observed three ancillary i , where plant procedural guidance did not appear to fully support ISI Program ac . ties:
- Quality Assurance Manual for ISI Related Activities: Inspectors observed that the Quad Cities quality assurance manual appeared appropriate for the Class 1 ISI activities observed. However, it failed to carry forth the ISI requirements for Class 2 and 3 records into the quality assurance manual. The manual did not i
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specify maintaining Class 2 and 3 records for the life of the plant as require * Quad Cities Procedure No. OCAP-0460-01." Plant Desion Chance Process:" ,
This procedure did not identify the ISI ASME Section XI program as a program j potentially impacted by a design change. The inspectors considered this a i weakness because of potential for the ISI program owners to be unaware of a plant modification.
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Lack of Site Procedure for ISI Calibration Standards Listed in Site Plan: The inspectors observed that NDE calibration standards were listed in the Quad Cities ISI Program Plan. However, there did not appear to be an assoc:ated site administrative control to implement the storage, modification and issuance of the ultrasonic calibration standards (and their drawings). The inspectors did not identify any technical concems during the observed RFO15 NDE activities as
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contract personnel appeared to adequately control the calibration standard Conclusions The ISI NDE procedures reviewed by the inspectors, were found to be in accordance with the ASME Code requirements. The inspectors identified three examples where ancillary plant procedural guidance did not fully support ISI Program activitie M4 Maintenance Staff Knowledge and Performance M4.1 Inadeauate Control of Relief Reauests Inspection Scope (73753. 73051. 73052)
The inspectors reviewed Quad Cities ISI program processes for requests for relief from ASME Code examination requirement Observations and Findinas l Procedural Guidance Lackina There was a lack of guidance goveming the identification, preparation, submital and processing of requests for relief from ASME Code examination requirements within the ISI program. The inspectors observed that due to poor control of relief requests, the following problems resulted:
- From 1994 to mid year 1998 Relief Request CR-05, for Code Class 1,2 and 3 repairs of 1-inch and smaller pipe was placed into the ISI Program although denied by the NRC in 199 Relief Requests CR-18 and CR-20, were placed into the ISI Program; however, they had not been approved by the NR Relief Request CR-02 committed to examining 25 percent of Category B- There were 119 welds scheduled for Unit 2 examination, yet 25 percent of the documented 533 welds listed for Unit 2 Category B-J, is 134. There was no additional information documented within the ISI program to readily justify this difference.
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b.2 Failure to Submit Relief Reauests The NRC had previously identified a concem over the limited extent of UT volumetric scan coverage obtained for the Unit 2 reactor pressure vessel (RPV) nozzle weld (N8B)
examined April 5,1993 (reference inspection report 50-254,265/97018). This limited examination had not been submitted to the NRC in the form of an ISI Code relief request as required by 10 CFR 50.55a(g)(5). The licensee subsequently documented that relief requests and/or an LER needed to be submitted to the NRC in Quad NTS ,
No. 254-123-97-02704, dated November 4,1997; PIF Q1997-0391610/22/97; I PIF Q1997-03604 September 25,19997; and Comed NOD-CA-98-003-JG " March 25, 199 Quad Cities TS surveillance 4.0.E required in part that ASME Code ISI examinations be in accordance with ASME Code Section XI and 10 CFR 50.55a(g)(5).10 CFR 50-55a(g)(5)(iv) requires "Where an examination requirement by the Code or addenda is determined to be impractical by the licensee and is not included in the revised inservice inspection (ISI) program as permitted by paragraph (g)(4) of this section, the basis for this determination must be demonstrated to the satisfaction of the Commission no later than 12 months after the expiration of the initial 120-month period of operation i and each subsequent 120-month period of operation during which the examination is I determined to be impractical."
During the current inspection, the inspector identified that in fact, multiple weld examinations (in excess of 50 Unit 1 and Unit 2 welds) performed during the 2d ten year ISI intervals (ending in 1993), did not meet ASME Code requirements in that the examinations were limited in the extent of coverage. Examples of welds with limited examination included the Unit 2 RPV nozzle weld N8B discussed above, the Unit i recirculation system tee to valve weld 02BS-F6, and Unit 1 RPV nozzle weld N1 A. As ,
of December 18,1998, the licensee had not included in a revised ISI program nor i demonstrated to the satisfaction of the NRC, the basis for their determination that the Code required examinations were impractical for the above welds. This is considered a j violation of 10 CFR 50.55a(g)(5) (VIO 50-254/98021-01(DRS); 50-265/98021-01(DRS)). I As this problem is generic to the Quad Cities ISI Program, the other welds with known limited coverage will not be cited at this tim ;
Inspectors also identified that the licensee had limited volumetric weld examinations in the current third ten year ISI interval during RFO14 that were not specifically identified as needing Code relief. The inspectors questioned the ISI staff on whether any RFO14 weldments examinations were scheduled for re-examination due to lack of sufficient records to identify the extent of examination. None were currently scheduled however, following discussions with the inspectors, the licensee had made efforts during RFO15 weld examinations to maximize examination coverage and record volumetric examination percentages as accurately as possibl :
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.. Conclusions A violation pertaining to the failure to request Code relief for multiple 1 and Unit 2 weld excminations with limited coverage was identified. Timeliness of corrective actions for this issue, originally identified in 1997, was considered poor. In general, the informal and poorly controlled relief request process contributed to several ISI Prograr,. related problem MS Maintenance Staff Training and Qualification l M5.1 Inservice Inspection NDE Qualifications Inspection Scope (73753. 73051. 73052)
Inspectors reviewed personnel qualifications and certifications of licensee and contract personnel performing ISI activities during RFO15., for compliance with ASME Code, SN-TC-1 A recommendations and applicable NRC requirement Observations and Findinas The contract personnel performing the RFO15 NDE were found to have training and qualifications in accordance with applicable ASME and NRC regulatory requirement The inspectors determined personnel certification records were properly documented and reviewed by Comed personnel and the ANil inspector for ASME Section XI inspections. The licensee Level 111 staff member performing independent UT reviews
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was also found to have training and qualifications in accordance with applicable ASME and NRC regulatory requirements Conclusions The personnel performing the NDE during RF015 inspections were found to have proper qualifications, which had been reviewed by the licensee staff and the ANi M6 Maintenance Organization and Administration M6.1 ISI Proaram Slow to Recover Inspection Scope (73753. '73052)
Inspectors reviewed the Quad Cities ISI Program Plan which implemented the Unit 1 and Unit 2 site ISI program. ISI program restoration documentation was also reviewed by the inspector Observations and Findinas in response to NRC previously identified problems with the Quad Cities ISI Program, the
licensee had initiated an ISI restoration effort that consisted of the following:
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(1) A ' discovery' phase which consisted of rigorous assessments of the Quad Cities iSI Program by Quad Cites staff, Comed corporate personnel and industry consultants. The discovery phase had many findings and appeared to be complete (2) A ' disposition' phase to review and evaluate the findings. This phase appeared to be close to issuing a summary report. However inspector review of the summary draft observed that in many cases, only broad categoria.; , Unit 1 RFO15 specific issues had been dispositioned. Most of the Unit 2,ssues and plant modifications, and some non-RFO15 Unit 1 individual system issues, remained to be reviewed and dispositioned, therefore this phase was considered only 65 percent complet (3) A ' Comed Corporate ISI' phase which would standardize the ISI Program across Comed sites. The licensee was developing a corporate ISI basis document and database, it was not complet (4) A Quad Cities ' documentation' phase which would incorporate the corrective resolutions, updates and revisions necessary to bring the ISI Program Plan into full compliance with Code and TS requirements. The ISI plan, schedule, drawings, UFSAR sections, and other documentation would be corrected, revised and updated._ Plant modifications and augmented inspections would also be incorporated into the ISI plan. Only a small percentage of work had been fully completed in this are (5) An ' implementation' phase which would perform the new examinations required for the corrected ISI boundary, missed examinations, and regularly scheduled examinations in the proper sequence required by Cod As a result of the ' discovery stage', Comed corporate and individual assessments concluded that the program plan was fragmented, and that several items did not meet TS, ASME Code or augmented requirements. It also indicated that staffing requirements for the ISI Program update, modification and performance of RFO15 activities was not sufficient. Some administrative procedures were identified to be weak in technical content and detail. Additionally the assessments found that the ISI program had not been updated since 1995, or kept in conformance with installed plant modifications or revisions to the database. The inspectors considered that the licensee had made an aggressive attempt to identify ISI issues. However, after a detailed review of the completed items within each phase, the inspector determined that at the time of the inspection, only approximately 40 percent of the total Quad Cities project to bring the ISI program into full compliance had actually been complete On January 7,1998, the licensee attributed the root cause for its poor ISI compliance at Quad Cities Units 1 and 2 to the fact that the site did not have an ISI ' owner' to assure all requirements were met. However during RFO15, the inspectors observed that in general, the Quad Cities ISI coordinator appeared to be minimally involved with the ISI
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efforts due to other assignments. While strong contractor oversight was not observed, contractor performance overall appeared effective, in 1997, the NRC had identified that the licensee may not have included all required safety systems within the scope of the ISI Program. After review, the licensee determined that certain boundaries were incorrect and should be extended. The inclusion of additional Class 2 RCIC, residual heat removal and emergency core cooling system safety related piping lines to the ISI Program boundaries and the inclusion of missed Class 3 integrally welded attachments increased the population of the Unit 1 ISI inspection by approximately 120 examinations. While the new examinations were required to be performed prior to the end of the 3* ten year interval, no UT examinations and only 20 VT and 4 magnetic particle examinations were performed during the current outage. This will require a considerable effort during the next outage, Conclusions Aggressive self assessments of the ISI function effectively identified a number of issue Implementation of corrective actions were slow, resulting in a significant amount of work yet to be accomplishe M8 Miscellaneous Maintenance issues M8.1 (Closed) Unresolved item (URI) 50-254/97018-04(DRS): 50-265/97018-04(DRS)):
Continued Integrity of the Reactor Pressure Vessel (RPV) Closure Stud The RPV studs interface with the reactor vessel flange to maintain the reactor coolant boundary. At the conclusion of the NRC September 1997 ISI inspection, the licensee could not demonstrate that an NRC approved "more rigorous visual examination," had been performed in lieu of replacement of the reactor vessel head closure stud Additionally, the licensee had not scheduled a Unit 1 or 2 shutdown to replace the head studs prior to 1998, when the head studs would reportedly exceed the ASME Code allowable fatigue cumulative usage factor (FCU) of Inspector review noted that the original evaluation for reaching the FCU had been based on predicted cycles. In 1997, to obtain a more precise prediction, another evaluation was performed using similar methodology based on the actual cycles experienced by the units. It was found that the previous evaluation had over predicted the number of operating cycles, and that the studs would not attain a FCU of 1.0 until the year 200 The inspectors review observed that Sections 3.9.1.1.1 and 5.1 of the UFSAR had been appropriately updated. For considerations after the year 2002, the inspectors observed that the licensee had implemented a two phase plan to assure the continued integrity of the closure studs. The first phase with a commitment date of March 1999, would demonstrate analytically, in accordance with ASME Section 111 Class 1, that the FCU would remain below 1.0 for the remainder of the license period. If a FCU below 1.0 could
' not be demonstrated, Phase 2 would consist of a volumetric examination program and the performance of a flaw tolerance evaluction. The inspectors observed that the
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licensee's projected goal was to have analysis and inspections (including necessary NRC approvals), in place at least one fuel cycle prior to the RPV studs reaching a usage I factor of The inspectors concluded that the ASME Code allowed FCU requirements of 1.0 had been met prior to the original evaluation expiration date of 1998, and that documented activities were in place which assured the continued structural integrity of the RPV stud This item is considered close M8.2 (Closed) Unresolved item (URI) 50-254/97018-01(DRS): 50-265/97018-01(DRS)): l Limited Weld Sca The inspector previously identified a concern that ASME Code requirements for UT examination coverage had not been met. This concern was prompted by the identification that a Q2R12 inspection of a reactor vessel nozzle weld with scan l limitations for which ASME Code Section XI volumetric inspection requirements !
appeared not to have been met. This examination had not been documented as limited and ASME Code relief request had not been approved by the NRC for this examinatio i
The licensee's failure submit relief requests when ASME Code volumetric inspection requirements were not met is considered a violation as discussed in Section M4.1 of this report. This item is close M (Closed) Violation (VIO) 50-254/97018-03(DRS): 50-265/97018-03(DRS)): Failure to Take Corrective Actions for ineffective IHSI Processes in Unit 1 Recirculation Pipe Weld Corrective actions for the issue consisted of a licensee cornmitment to inspect each Unit 1 GL88-01 Category C weld treated with the IHSI process in accordance with a Category D frequency (100 percent every 2 fuel cycles) and a TS change. Inspector review of the examinations scheduled for RFO15 determined that the licensee complied with the Category D schedule. Inspector review also noted Quad Cities technical specifications had been updated appropriately to incorporate GL88-01 commitments including staff positions on schedule, methods, personnel and sample expansion. This item is close The inspector reviewed the licensee's closure activities and found them to be adequate although inspectors observed that the licensee did not see a need rigorously address the broader issue of the IHSI welds in Unit V. Manaaement Meetinas XI Exit Meeting Summary The inspectors presented the inspection results to members of licensee management at the conclusion of the inspection on December 18,1998. The licensee acknowledged the findings presented and did not identify any of the potential report input as proprietar F:
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PARTIAL LIST OF PERSONS CONTACTED Co,viir.or, wealth Edison (Comed) !
W. Beck, Regulatory Assurance
' J. Dimmetto Jr., Site Vice President- ;
' H. Do, Corporate Engineering Programs
. V. Geotz, ISI Engineer K. Johnson, ISI Coordinator !
G. Larson, Engineering Project Supcivisor C. Peterson, Regulatory Assurance Manager- l
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T. Robeds, Corporate Engineering Programs ~ l
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R. Svalson, Operations _ _
B. Wilson, Corporate Level ill T. Wojeck, Engineering Programs, IWI Coordinator D. Wozniak, Engineering Manager, Hadford Steam Boiler insoection & Insurance Comoany G. Bosley, ANil lilinois Deoartment of Nuclear Safety (IDNS) !
' R. Ganser, Resident inspector L. Sage, Head, Code Compliance Section Lambert McGill Thomas (LMT) -
L. Davis, Site Supervisor T. Blechinger, ISl examiner T. Gahan, ISI Examiner -
Q. Loredo, ISI Examiner D. Tinley, Records Manager General Electric (GE) I
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'J. Easton, Site Supervisor ,
H. Schlort, Lill . l Comed Contractors :
R. May, Contract'ISl Oversight US Nuclear Reaulatory Commission (NRC)'
L. Collins, RI
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. C.' Miller, SR l K. Walton , RI
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INSPECTION PROCEDURES USED IP 73051: Inservice Inspection - Review of Program IP 73052: Inservice Inspection - Review of Procedures IP 73753: Inservice Inspection IP 73755: Inservice inspection - Data Review and Evaluation ITEMS OPENED, CLOSED,' AND DISCUSSED
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i Ooened 50-254/265/98021-01 VIO Multiple Examples of Failure to Submit Relief Requests Closed 50-254/265/97018-04 URI Continued Integrity of the Reactor Pressure Vessel (RPV) Closure Studs 50-254/265/97018-01 URI Limited Weld Scan 50-254/265/97018-03 VIO Failure to Take Corrective Actions for ineffective IHSI Processes in Unit 1 Recirculation Pipe Welds Discussed None
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LIST OF ACRONYMS USED ANil . Authorized Nuclear inservice Inspector ASME American Society of Mechanical Engineers ASNT American Society of Nondestructive Testing CFR Code of Federal Regulations l Comed Commonwealth Edison Company l 'DRS Division of Reactor Safety l
ECCS Emergency Core Cooling System FCU Fatigue Cumulative Usage Factor G General Electric GL- Generic Letter IDNS lilinois Department of Nuclear Safety IFl Inspection Follow-up item IGSCC Intergranular Stress Corrosion Cracking IHSI Induction Heat Stress improvement IR inspection Report ISI inservice inspection MRDC .~ Motorized Rotating Pancake Coil NC2 Non-destructive Examination NRC Nuclear Regulatory Commission PDI Performance Demonstration Initiative PDR NRC Public Document Room PT Dye Penetrant Test RFO Refuel Outage RG Regulatory Guide RHR Residual Heat Removal System RPV Reactor Pressure Vessel RT Radiographic Testing UFSAR Updated Final Safety Analysis Report URI Unresolved item UT Ultrasonic Testing VIO Violation VT Visral Testing
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PARTIAL LIST OF DOCUMENTS REVIEWED l
l l Comed Procedure No. NDT-C-30, Revision 6 " Ultrasonic Examination of Reactor Vessel Welds l
to NRC Regulatory Guide 1.150" Comed Procedure No. NDT-C-48, Revision 2 " Ultrasonic Examination of Reactor Vessel Closure Studs" Quad Cities NSP-ER-3016, " Implementing Procedure for Conduct of ISI Activities", Revision 0 Quad Cities Procedure No. QCAP-0460-01, " Plant Design Change Process"
- Quad Cities Document No. NOD-CA-98-003-JG,"lSi Program Assessment Quad Cities Units 1 and 2, Final Report", dated March 25,1993 Quad Cities Document No. QC0040.F01," Draft Quad Cities ISI Assessment Disposition Report", Revision 0 Quad Cities Report No. PlF Q1998-04967," Reactor Recirculation System lGSCC Root Cause Report", dated November 30,1998 Comed Letter No. SVP-97-320 dated December 30,1997; Letter from E. Kraft, Jr. (Comed) to ,
USNRC Document Control Desk, providing results of calculation No. QDC-0200-S-0536, Revision 0," Vessel Fatigue Evaluation Considering Actual Thermal Cycles For Quad Cities Nuclear Station Units 1 and 2 as of November 1997" Comed Letter No. SVP-98-068 dated February 26,1998; from E. Kraft, Jr. (Comed) to USNRC Document Control Desk, transmitting Comed's long term plan to assure the continued integrity of the RPV closure studs for Quad Cities Nuclear Station Units 1 and 2" Quad Cities Updated Final Safety Analysis Report (UFSAR) Sections 3.9.1.1.1," Reactor Pressure Vessel Fatigue Evaluation"; Section 5.3.1.7 " Reactor Vessel Fasteners" and 5. Letter from R. Stols, Comed to T. E. Murley (NRC), submitting GE Report SASR 89-02 " Vessel Fatigue Evaluation Considering Revised Thermal Cycles For Quad Cities Nuclear Station Units 1 and 2," Revision 2 SASR 89-02 " Vessel Fatigue Evaluation Considering Revised Thermal Cycles For Quad Cities Nuclear Station Units 1 and 2," Revision 2 Letter from L. Olshan (NRC) to T. Kovach (CECO), dated February 13,1991, " Issuance of Amendment (TAC Nos. 75374 and 75375)"
Quad Cities GL88-01 commitment letter No. SVP-97-265 dated November 20,1997
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