1CAN099703, Forwards Response to NRC Ltr Re Violations Noted in Insp Rept 50-313/97-201 on 970210-0304.Corrective Actions:Cst TS Bases Currently Being Evaluated & Rewritten

Forwards Response to NRC Ltr Re Violations Noted in Insp Rept 50-313/97-201 on 970210-0304.Corrective Actions:Cst TS Bases Currently Being Evaluated & Rewritten

ML20211C471
Person / Time
Site:	Arkansas Nuclear
Issue date:	09/22/1997
From:	Mims D ENTERGY OPERATIONS, INC.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
1CAN099703, 1CAN99703, 50-313-97-201, NUDOCS 9709260217
Download: ML20211C471 (13)

Text

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i September 22,1997 1CAN099703 l l

U. S. Nuclear Regulatory Commission .

I Document Control Desk hiail Station OPl 17 Washington, DC 20555

Subject:

Arkansas Nuclear One Docket No. 50-313 License Nos. DPR 51 Response to Inspection Report 50 313/97-201 Gentlemen:

During the period February 10, 1997 through hfarch 4,1997 the Nuclear Regulatory Commission (NRC) performed a design inspection of the Arkansas Nuclear One, Unit 1 (ANO-1) Emergency Feedwater System (EFW) and the Decay Heat (DH)/ Low Pressure Injection System (LPI). The purpose of the inspection was to evaluate the capability of the systems to perform safety functions required by their design basis, adherence to the design and licensing basis, and consistency of the as-built configuration with the Final Safety Analysis Report (FSAR).

Attachment one contains a listing ofinspector follow-up and unresolved items which includes a response and schedule of completion for each item. The corrective action schedules are based on the safety significance of the identified condition, the priority of the actions relative to other activities, and the plam conditions necessary to complete the actions. With the exception of actions tied to future refueling outages, the identified items are scheduled to be completed by the end of1998.

ANO appaciates the NRC recognition of the strengths noted in the engineering area. This includes the capability and professionalism of our staff, the self-assessment performed prior to the inspection and acknowledgment of our selfidentified items. The technical and public exit meetings were very positive and it was understood that the majority of the identified items would be classified as inspector follow-up items. While it is understood that exit meetings are done prior to management review and that characterization of issues could change upon review by NRC management, the reclassification of a majority of the items from inspector follow-up items to unresolved items appears to be a noticeable departure from the way the 9709260217 970922 iG" .H PDR ADOCK 05000313

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U. S. NRC September 22,1997 FCAN099703 Page 2 issues were characterized at the exit meeting. ANO would appreciate any insights regarding the recharacterization of these issues.

Should you have questions or comments, please call me at 501858-4601.

Very tmly yours,

& /t1 e. w/- a Dwight C. Mims Director, Nuclear Safety DCM/RMC Attachments

U. S. NRC September 22,1997 ICAN099703 Page 3 cc: Mr. Ellis W. Merschoff Regional Administrator U. S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 400 Arlington, TX 760118064 NRC Senior Resident Inspector Arkansas Nuclear One P.O. Box 310 London, AR 72847 Mr. George Kalman NRR Project Manager Region IV/ANO-1 & 2 U. S. Nuclear Regulatory Commission NRR Mail Stop 13113 One White Flint North 11555 Rocksille Pike Rockville, MD 20852

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Attachment to ICAN099703 Page1of10 ATTACIIMENT 1 RESPONSE /SCilEDULE IFI $0-313/97 401-QL Condensate Storage Tank (CST) Technical Specification Bases Revisions Response: To address this selfidentified item, the CST technical specification bases are currently being evaluated and rewritten. ANO 1 is in the process of developing Improved Standard Technical Specifications (ISTS) and the revised CST bases will be included in the initial submittal, Currently, ANO plans to submit the ISTS by the end of 1998.

l URI 50 313/97-201-02 EFW Flow Rates Exceeding Babcock & Wilcox (B&W)

Recommendations Response: To address this situation, a condition report was issued which included an operability assessment and root cause which determined there were no steam generator operability or safety concerns associated with exceeding the cross flow limit.

Additionally, a more comprehensive evaluation of the cross flow rate limit was performed and a new maximum allowable steady state flow rate of 2214 gpm has been established. This is an increase of approximately 700 gpm from the initial B&W established limit. Since the EFW flow rate will not exceed 1858 gpm following a main steam line break with the level control valves 100% open, no action to limit the maximum attainable EFW flow rate is necessary. This issue was effectively resolved prior to the exit meeting.

The _ ANO-1 transient cycle logging _and reporting procedure was revised to provide guidance for determining excessive EFW flow and guidance for initiating a condition report if it becomes necessary to evaluate an excessive crossflow condition.

URI 50 313/97 201-03 EFW Piping Configuration Differences Rcsponse: To address this selfidentified item, calculation 82 D 2086-02 Determination of Pipe Si:e and NPSH for EFW Pump 7A and 7B Suctionfrom CST T-#B will be revised by March 1,1998.

Attachment to 1CAN099703 Page 3 of 10 URI 50 313/97 201-04 Inadequate Piping Pressure and Temperature Specifications Response: To address this self identified item, calculation 88 E-0100-16 concerning piping pressure and temperature calculations will be revised by January 15,1998.

URI 50-313/97 20105 Evaluation of EFW Pump Room Environment Response: To address this selfidentified item which concerns the postulated failure of non-Q steam traps, an ANO 1&2 condition repon was issued which required the performance of present and past operability assessments for both units, a root cause analysis and hvelopment of a corrective action plan.

The operability assessment for ANO-1 determined that the non-Q steam traps and associated piping will not fait during a seismic event, if a steam trap fails open the ambient EFW pump room temperature will not rise to a level where other essential components in the room become inoperable, and operator action is credited to terminate the steam blowdown. For ANO 2, the non-Q steam traps and associated piping will not fail during a seismic event. If a steam trap fails open the steam is vented outside the EFW room and temperature rise is not a concern.

The root cause analysis determined that the original design of the EFW steam traps is inadequate for both ANO-1 & 2 and modifications will be performed to upgrade the system. Modifications for ANO-1 will be completed by the end of% fueling outage IRl4 currently scheduled for the Spring of 1998 and for ANO 2 by the end of refueling 2Rl'a currently scheduled for the first quarter of 1999 URI 50-313/97-201-06 Drawing and Calculation Revisions Response: As a result of the 10CFR50.54(f) review, ANO is implementing several improvements to address the maintenance, ownership, and control of calculations. The overall philosophy for maintenance and ownership of calculations will result in fewer discrepancies and improved quality of design basis calculations. Additionally, efforts to improve the accuracy of the calculation database has resulted in improvement in the retrievability of calculations. Other improvements will include the development of an electronic calculation cover sheet and process, and a system effon to standardize the calculation process.

Following the AE design basis inspection, a corporate assessment team performed an additional ANO design basis evaluation which resulted in

Attachment to 1CAN099703 Page 3 of10 recommendations for improvement of calculations which will be implemented. These include the review of critical mechanical and instrument uncertainty calculations and the inclusion of the recommendations of a quality action team effort into the ANO calculation process.

The following calculations will be revised as applicable by January 15,  ;

1998 to address identified concerns 1

e 92-E-0021 01, Emergency Duty Cycle and Battery Si:Ing Calculation

• 80 D 1083A-02, EFIC DC Valve torque Calculation Under Reduced Voltage Condition The following calculations will be revisad by March 1,1998 to address the identified concerns.

• 82-D-2086 01, Volume of T-41B Requiring Tornado Missile Protection, e 82-D 2086-02, Determination of Pipe SI e and NPSH for EFIV Pump 7A and 7B Suctionfrom CST T-41B e 88 E-0086 01, IE bulletin 88-04 Review for P7A and P7B Afinimum Flow Evaluation

• 92 E 0077-04, ElRYPump Performance Requiremer,;s The inspection report noted that calculation 92 E-0074-04 would supersede calculations 80-D-1083B 102 and 80 D-1083B-102A, Calculation 92 E-0074-04, mentioned in ti.e inspection report, does not exist, however, calculation 92E-0077-04 is closely related to the 1083B series noted above. An evaluation to determine if the noted 10838 calculations should be superseded will be completed by March 1,1998.

IFI 50-313/97-201-07 Modification Work Procedure Revisions Response: To ensure the consistent installation of conduit, the control of modification work procedure was revised to include instructions for the development of a single line drawing depicting the types of supports used, the support spacing and the conduit layout. Inspection of newly installed conduit is performed by the responsible modification engir.evr subsequent to job completion.

Attachment to ICAN099703 Page 4 of10 IFl 50-313/97-201-08 Additional Vendor Information Necessary for Revised Cable Pulling Calculation Response: Updated cable information will be obtained from cable vendors for approximately 10% of the cable codes listed in the cable mirdmum bend radii review table. The data obtained will be that which is available for a particular or comparable cable type and will represent the cable design criteria. This information is expected to be obtained by January 15,1998.

The updated cable information obtained will be used to revise the calculation for each of the applicable cable codes. Additionally, the data will also be compared with existing cable data to establish the accuracy of the table values foi minimum cable bend radii and conduit sizing. The results of this comparison will also provide justification to accept the remaining table values or establish the need to obtain additional vendor data. This action will be completed by March 1, 1998, 1

l IFl 50 313/97-201-09 Use of Tefzel Cable Ties and PVC Conduit Inside Containment Response: ANO-l&2 electrical drawings E-59 and E 2059, Conduit and Cable Tray Notes and Details, contain the criteria for the use of cable ties.

The cable tie criteria will be evaluated and combined to address the use of cable ties in vertical trays. The combined criteria will then be included in Procedure 6030.109, Installation of Electrical Cable and Wire. This will ensure consistent use of cable ties in vertical trays.

This will be completed by January 15,1998.

URI 50-313/97-201-10 Maintenance, inspection and Testio;, of Cathodic Protection and Grounding Systems Response: Actions to improve the cathodic protection and grounding systems for both ANO l&2 include:

• Cathodic protection system anode failures will be evaluated by December 15, 1997 to identify the source of the failures.

Information gathered as a result of this evaluation will be used to develop an equivalency evaluation for replacement anodes and other system enhancements by December 15,1998.

• An evaluation ofindustry cathodic protection maintenance practices will be conducted. The results of the evaluation will be factored into the ANO maintenance program as applicable. This will be completed by June 15,1998.

Attachment to 1CAN099703 Page 5 of10

• An evaluation of industry grounding maintenance practices will be conducted. The results of the evaluation will be factored into the ANO maintenance program as applicable. This will be completed by June 15,1998.

IFI 50-313/97-J01-11 Verification of Calculation Changes Associated with DC Batteries Response: The ANO-1200A battery chargers were upgraded with 400A chargers during 1995 and 1996. This required that battery recharge times be ,

r ecalculated. The battery recharge time is not dictated by either  ;

technical ;pecifications or the FSAR. Engineering procedures require that asscciated amending calculations be reviewed prior to the revision of a calculation and the information provided by amending calculations is readily available. Amending calculation 93-D-1010-04 Recharge 1

Time for DO6 and DO7 with Changes per DCP-93-1010, will be incorporated into calculation 92-E-0021-04, Revision 1, Battery DO6 and D07 Recharge Time, by January 15,1998. Improvements to the calculation courol process are discussed in URI 50-313/97-201-06.

l IFI 50-313/97-201-12 NRC Review of Current Design Basi:. for Bypassing EDG Protective Trips Response: ANO-1 is committed to Safety Guide 9, Selection ofDiesel Generator Set Capacityfor Standby Power Systems, dated March 10,1971 which does not require bypassing EDG protective functions during accident conditions. A review of the ANO-1 EDG reliability data for the past seven years has indicated that the non-bypassing of EDG protective functions is not a concern. The reliability data indicates that only one isolated EDG start failure occurred due to the possible malfunction of a low lube oil indicator (protective function) during refueling outage 1R10 (1902).

Witt, the exception of one isolated failure of an EDG protective function, ANO-1 EDG's have exhSited excellent starting and mn performance. Additionally, EDG health is monitored through the ANO reliability program which complies with guidance of NUMARC 87-00 Initiative 4, ACPower Availability.

ANO is concerned that trip hardening or hypassing oficportant EDG protective functions may result in a greater likelitcod of serious damage to this vital equipment, in contrast to the presumed reliability improvement by prevented unwarranted tripping. Therefore, the non-tmpassing of EDG protective functions is not a design weakness nor

Attachment to ICAN099703 Page 6 of 10 safety concern and a modification to bypass the piotective functions is not considered appropriate.

IFI 50-313/97-201-13 Reconstitution of Tornado Analysis for EDG Exhaust Stacks Response: For this self-identified item, reconstitution of the tornado analysis for the ANO-1 EDG exhaust stacks has been essentially completed. The analysis determined that as a prudent measure stiffener rings should be installed at the top of each exhaust stack and the rain hoods removed.

The modifications for ANO-1 will be completed by refueling outage IR14 currently scheduled for the Spring of 1998 and for ANO-2 by refueling outage 2R13 currently scheduled for the first quarter of1999. ;i URI 50-313/97-201-14 Lack ofTesting Unit I hiCCBs Response: An evaluation of this self-identified item determined that as a prudent measure appropriate ANO-1&2 hfCCBs should be periodically tested or replaced.

A limited scope ANO-1 reactor building penetration AfCCB testingheplacement program will be developed and implemented during refueling outage IR 14 cur:ently scheduled for the Spring of 1998. Full program development will be completed by the end of 1998.

The remaining ANO-1 safety-related hiCCBs will be categorized by significance and a testing or replacement program will be developed for those considered risk significant, by the end of 1998.

ANO-2 containment penetration hiCCBs are tested per technical specification requirements. The remaining ANO-2 safety related

, hfCCBs will be categorized by significance and a testing or replacement program will be developed and implemented, for those considered to be r% significant, during refueling outage 2R13 curren;ly scheduled for 10 first quarter of1999.

URI 50-313/97-201-15 Lack ofIncluding all Safety-Related Fuses in Procedure

. 8 Response: As stated in the inspection report, ANO developed a fuse control program based on commitments made as a result of an electrical distribution system functional inspection. The scope of the commitment was to include only those fuses in cabinets associated with the electrical drawing upgrade project (EDUP) which was limited to selected cabinets in the ANO-l&2 control rooms. These cabinets contain the majority of ANO safety-related fuses. ANO agrees that minor discrepancies have been identified in the control of fuses.

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Attachment to ICAN099703 ~

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Specifically, a review of condition reports issued for both ANO-l&2 within the past four ye.ars reveals only seven related to wrong size or type of fuse. Only three of these cases corresponded to safety-related fuses and those discrepancies did not affect circuit operability.

Therefore, the ANO corrective action process appears effective in a resolving existing minor discrepancies.

ANO also agrees that enhancements to the fuse control program can be made. The current fuse control program is limited to selected control room cabinets, and the scope of the program will be expanded to include fusis in selected safety-related DC distribution equipment in both Ah0-l&2. This will be completed by June 30,1998.

An additional enhancement will require the review of the fuse control program to verify, correct or add fuses when a design change is raade to a safety-related circuit. Procedure revisions to implement this enhancement vill be completed by June 30,1998.

URI 50-313/97-201-16 FSAR Discrepancies A comprehensive proactive review of both the ANO-l&2 ,afety analysis reports is currently being performed. This review effort is described in letter CNRO-97/00010, EOI Licensing Pasis Assessment and UFSAR Review Initiatives, dated May 7,1997 and i' designed to identify the type discrepancies noted in the inspecticn report. The noted-discrepancies will oc corrected in the 1998 submittal of the ANO-1 SAR.

URI 50-313/97-201-17 Ineffective Resoluticn of - Previous Corrective Actions Assos.ted with Solenoid Valve Leakage Response: ANO self-identified that the EFW steam admission solenoid valves have. experienced leakage in the past causing check valve chatter, and maintenance efforts have only been minimally successful in correcting the leakage. Periodic inspections of these check valves reveal no sign of abnormal wear on the seating sur' aces. The check valves have a stellite seating surface which ensures their reliability and durability.

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Additionally, these check valves are ir.%ded in the inservice testing program which requires quarterly flow testing and-18 month reverse flow tests.

A past evaluation of this condition determined that the steam leakage has not degraded system performance. It was subsequently determined that the performance of the system did not justify installation of a modification to eliminate the leakage.

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Attachm:nt to ICAN099703 Page 8 of10 The need for solenoid valve modification was reevaluated piior to each outage and system perfonnance has not justified the implementation of a modification. However, during refueling outage IR13 (1996) the inspection of emironmentally qualified elastomers in the steam admission solenoid valves revealed that more frequent maintenance may be required in the future. This condition is tracked via the ANO condition reporting system and appropriate actions are beiiig taken as necessary.

Corrective actions associated with the EFW steam admission solenoid

! valve leakage have been appropriate. The check valves have been reliable and the overall system performance has been excellent. The system and equipment performance is being monitored for any adverse trends and the need for modifying the system will be reevaluated per s the ANO corrective action system.

URI 50-313/97-201-1% Lack of Seismic Sepport of OTSG Pressure Transmitters URI 50-313/97-201-19 Lack of Design Basis for Support of OTSG Instmment Sensing Lines Response: Upon identification, a condition report was issued which included an operability assessment and root cause evaluation of the condition. The operability assessment determined that although the instmment sensing lines were not supported in accordance with standard drawing details the installation would be able to perform the intended safety function.

The causes of the condition were determined to be inadequate training of personnel involved in the installatien and maintenance ofinstrument tubing, the failure to adhere to plant configuration documents and the inadequacy or inaccessibility of design doc'imentation in some cases.

Planned corrective actions include the redefinition of the design qualification of seismic category 1 tubing with associated design basis documentation redsions as necessary, field walk down of affected tubing and revi" as necessary, and training of personnel responsible for the installation e.a maintenance of seismic tubing. These actions will be completed during the fourth quarter of 1998.

URI 50-313/97-201-20 Inadequate Work Plan for the Control of Post Maintenance Testing Response: The work plans for CV-4804 and CV-1845 were revised to require verificati3n that the limit switch rollers are properly aligned after

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Attachment to ICAN099703 Page 9 of 10 maintenance. There are no other valves in ANO-1 or ANO-2 with this limit switch configuration.

URI 50-313/97-201-21 Inadequate 50.59 Review Associated with the Removal of Borated Storage Tank (BWST) Vacuum Breaker and Follow-up Corrective Actions Response: The BWST vacuum breaker was removed due to a cracked flange.

Since the vacuum breaker could not be reinstalled, a long term foreign material exclusion (FME) cover was placed on the blank flange. The FME cover consisted of a blind flange separated from the tank flange by a gap of approximately one inch with a wire mesh FME screen over the opening. The initial operability assessment did not consider the FME screen covering the one inch gap and the resuhant flow blockage A more detailed operability assessment was performed and it was i determined that the FME screen did not reduce the total flow area to less than that required for operability. The initial operability assescment was appended to include the FME screen analysis.

The inspection report stated that the BWST vacuum breaker remoni pursuant to 10CFR50.59 was inadequate since it did not consider the flow restrictions caused by the actual installed configuration of the FME screen. The operability evaluation was the only deficient document as it did not address the FME screen cover. 10CFR50.59 determinations / evaluations are not normally performed as a part of operability assessments.

The final resolution of the BWST FME cover issue will include completion of actions in condition reports 1-97-0019 and 1-97-0031, and an evaluation of the temporary BWST FME cover design. The evaluation, to be completed by March 1,1998 will consider the following options:

. Deeming the current configuration per nanent

• Enhancing the current configuration e Redesign the FME cover e Replacement of the vacuum breaker URI 50-313/97-201-22 Revised Calculations Associated with BWST Vortexing and Pump Net Positive Suction Head (NPSH)

Response: To address this self-identified item, a condition report was issued which included an operability assessment that determined there weie no operability concerns with the ECCS pumps.

Attachment to 1CAN099703 '

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A drawdown analysis of the BWST during the transfer of the ECCS suction to reactor building sump will be performed by December 15, 1997.

The results of the drawdown ans will be factored into the reactor building spray, and the high pressui , and low pressure injection NPSH 1 calculations as appropriate by January 15,1998, URI 50-313/97-201-21 Inadequate 50.59 Evaluation Associated with BWST Releases Response: The 50.59 evaluation for the temporary alteration of the BWST pressure and vacuum relief valve was revised to address the effects of post accident releases on control room dose. h

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