ML20084A093

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Informs That Plant Revising Commitment Response Date from 950531 to 951101 in Response to Insp Repts 50-373/91-19 & 50-374/91-19
ML20084A093
Person / Time
Site: LaSalle  Constellation icon.png
Issue date: 05/19/1995
From: Benes G
COMMONWEALTH EDISON CO.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9505300227
Download: ML20084A093 (7)


Text

, Ormnwnw chh itiswin Compan) i 100 Opm 11at c Dow nun ( rm e. II. 60il 5 May 19,1995 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555

SUBJECT:

LaSalle County Nuclear Power Station, Units 1 and 2 Supplemental Response to EDSFI Violation 373/91019-07 and 347/91019-07 Safety Related Contact Testing Assurance Program Request for Schedule Extension NRC Docket Nos. 50-373 and 50-374

REFERENCES:

1. T.J. Kovach letter to USNRC dated January 16,1992, transmitting response to EDSFI report.
2. T.O. Martin letter from USNRC to L.O. DelGeorge dated March 12,1993, transmitting Inspection Report Nos. 50-373/93002 and 50-374/93002.
3. J.L. Schrage letter to USNRC dated March 15,1993, regarding the Quad Cities SRCTA program.
4. G.G. Benes letter to USNRC dated December 20,1993, transmitting supplemental response to subject EDSFI violation.

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5. G.C. Wright letter from USNRC to Mr. W. Murphy dated January 12,1994, approving the requested change in the i completion schedule for the SRTCA project.

In our original response to the subject violation (Reference 1), LaSaile County Station committed to complete a safety-related contact testing assurance program by May 31,1994, to prevent reoccurrence of this violation. In Reference 2, the NRC closed this issue based on the progress performed to date and this commitment. In Reference 4, LaSalle County Station revised the commitment response date to May 31,1995. Reference 5 provided the NRC approval of the change in this commitment response date.

This letter is to inform you that LaSalle County Station is revising the commitment response date from May 31,1995, to November 1,1995. Attachment A provides the justification for this schedule change and the current status of this l project. l l

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USNRC 2 May' 19,1995 To the best of my knowledge and belief, the statements contained above are -

true and correct. In some respect these statements are not based on my personal knowledge, but obtained information furnished by other Commonwealth Edison employees, contractor employees, and consultants. Such information has been s reviewed in accordance with company practice, and I believe it to be reliable, i

Please direct any questions you may have concerning this matter to this office. l Sincerely, Q GB W Gary G. Benes Nuclear Licensing Administrator Attachment A cc: J. B. Martin, Regional Administrator - RIII P. G. Brochman, Senior Resident Inspector - LSCS >

W. D. Reckley, Project Manager - NRR Office of Nuclear Facility Safety - IDNS

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ATTACHMENT A Supplemental Response To Inspection Report 50-373/91019; 50-374/91019

'- Violation 373/91019-07; 374/91019-07 Safety Related Contact Testing Adequacy (SRCTA) Proiect INTRODUCTION LaSalle County Station is revising the completion date for the Safety Related Contact Testing Adequacy (SRCTA) project from May 31,1995, to November 1, 1995. The scope of work for this project includes the review of the electrical

drawings and station procedures for about 37 systems, and this extension will

- provide additional time for reviewing these systems, evaluating the results of this project, and implementing any required corrective actions. -

3 Although the scope of work for the SRCTA project has been expanded to include 4

the review of contacts which perform a function identified in the UFSAR or GE system design specifications as explained below, our original response to the subject EDSFI violation only concerned the review of contacts which perform a Technical Specification function (ref.1 and 2). Therefore, to avoid any 2

misunderstandings, the new commitment date listed above is only for the expected completion date of the SRCTA project with respect to the Technical Specification related contacts. The review of the remaining contacts is expected to extend l beyond this date.  :

BACKGROUND l

During the Electrical Distribution System Functional Inspection (EDSFI) of October 7 through November 8,1991, a Level IV Violation was issued for failing to adequately test the offsite power undervoltage relay logic circuitry. In our response to this item, LaSalle County Station committed to implement the SRCTA  !

project to prevent reoccurrence of this violation and to complete this project by May 31,1994. Per references 4 and 5, the completion date was revised to May 31, 1995.

l PURPOSE The purpose of the SRCTA project is to ensure that all safety-related contacts which perform a function identified in the Technical Specifications, Updated Final L Safety Analysis Report (UFSAR), or Nuclear Steam Supply System (NSSS) vendor (GE) design specifications are properly tested by station procedures. A secondary ht\nla\lasalle\srefin.wpf3 i

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purpose of this project is to develop a database which relates Technical Specification and UFSAR functional requirements, testing procedures, and schematic diagrams to the devices and associated contacts.

SCOPE OF WORK The scope of work for the SRCTA project consists of the following four phases:

1. Review of the Technical Specifications, UFSAR, and GE design specifications to identify system functions and surveillance requirements.
2. Review of the schematic diagrams to identify the contacts which perform a function identified in item 1 or a miscellaneous function.
3. Review of the station procedures to determine if these contacts are adequately tested.
4. Implement corrective actions as necessary.

All safety related systems and non-safety related systems with safety-related contacts are included in the scope of work.

Any concerns or issues that are identified by the SRCTA program will be resolved as described in reference 3.

PROJECT STATUS The evaluation of the Technical Specifications, UFSAR, and GE design specifications has been completed.

Listed in chronological order, the following systems have been reviewed by NUS, the architect engineering firm contracted to perform the SRCTA review:

1. Low Pressure Core Spray (LPCS)
2. High Pressure Core Spray (HPCS)
3. Residual Heat Removal (RHR)
4. Automatic Depressurization System (ADS)
5. Standby Gas Treatment (VG)
6. Reactor Core Isolation Cooling (RCIC)
7. Primary Containment Isolation (PC)
8. Standby Liquid Control (SC)
9. Reactor Protection (RP)
10. Diesel Generator (DG)
11. Auxiliary Power (AP)
12. Control Rod Drive (RD) *
13. Hydrogen Recombiner (HG)
14. Neutron Monitoring (NM) k:\nla\latalle\sicfin.wpf4

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15. Leak Detection (LD)
16. Primary Containment Vent and Purge (VQ)
17. Feedwater (FW) *
18. Main Steam (MS)
19. Reactor Recirculation (RR) *
20. MSIV Leakage Control (LC)
21. Reactor Water Cleanup (RT) *
22. Reactor Building Ventilation (VR) *
23. Containment Monitoring (CM)
24. Control Room Ventilation (VC) *
25. Auxiliary Equipment Room Ventilation (VE) *
26. Accident Monitoring (AM)
27. Instrument Nitrogen (IN)
28. Reactor Building Equipment Drains (RE)
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29. Reactor Building Floor Drains (RF) *
30. Reactor Building Closed Cooling Wator (WR)
31. Primary Containment Chilled Water (VP)
32. Suppression Pool Monitoring (CM)

LaSalle engineering has performed initial evaluations of the NUS reports with respect to Technical Specification surveillance requirements except for those systems marked with an asterisk (*). The findings are summarized below.

The remaining systems to be reviewed by NUS are listed below:

1. Turbine-Generator (TG)
2. Refueling (F21)
3. Remote Shutdown (C61)
4. Fire Protection (FP)
5. Seismic Monitoring (SI)

SUMMARY

OF FINDINGS The review of the schematic diagrams for the above systems completed to date has identified approximately 8970 contacts which perform a Technical Specification function,1760 contacts which perform a function only described in the UFSAR or GE design specifications, and 1700 contacts which perform miscellaneous functions per unit.

The review of the applicable surveillance and test procedures for the systems evaluated by LaSalle engineering has identified only the following two inadequately tested Technical Specification functions:

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1. APRM setdown high neutron flux trip. Technical Specification 3.3.1 requires the Average Power Range Monitor (APRM) setdown high neutron flux trip (s 15% of rated thermal power) to be operable in Operational Conditions 2,3, and 5 (i.e., Startup, Hot Shutdown, and Refueling), and the interlock between the Reactor Mode Switch and APRM high neutron flux trip channels was fbund to be untested. The relays which performed this function in the circuit were replaced with " dummy" relays during the calibration of the APRMs and used to simulate the positions of the Reactor Mode Switch. The position of the Reactor Mode Switch (Run or Startup/ Hot Standby) determines whether the fixed or setdown high neutron flux trip (i.e., s 118% or s 15% of rated thermal power)is in effect. The short term corrective actions consisted of testing this interlock per a special test procedure during the subsequent outage on each unit. The long term corrective action consists of revising the surveillance test procedures to ensure this interlock is tested every refueling outage. This event is further described in LER #94-012-00.
2. Recirculation flow unit rod block. Technical Specification 3.3.6 requires a 2 control rod withdrawal block for the Recirculation Flow Unit upscale, inoperative, and comparator trip functions while in Operational Condition 1 (i.e., Run), and the interlock between the Recirculation Flow Units and Rod Block Monitoring (RBM) syscem was found to be untested. The instrument channels were found to be tested only up to the relays which perform this function. The corrective actions consisted of testing this interlock per a revised functional test procedure. This event is further described in LER
  1. 95-006-00.

This review also identified testing deficiencies with the Standby Liquid Control and MSIV Leakage Control systems. Although existing testing met all Technical Specification surveillance requirements, the testing that was performed did not ,

verify all contact logic for these systems. Subsequently, logic tests have been successfully completed on both units for the Standby Liquid Control system and on Unit 2 for the MSIV Leakage Control system. The logic test for the Unit 1 MSIV Leakage Control system is scheduled to be performed during an upcoming outage.

In addition, these logic tests have been or will be added to the 18 month surveillance for these systems.

With regards to the systems reviewed by LaSalle engineering to date, the remaining contacts that were identified by NUS to be untested have been determined to be either adequately tested in accordance with Technical Specification requirements or not required to be tested. For the contacts which perform a Technical Specification function, this review concluded that the safety related function of these contacts are verified by existing surveillance testing. For the other untested contacts that were classified by NUS to be Technical Specification related, this review found that these contacts perform only alarm, kt\nla\lasalle\srefin.wpf6 1

I indication, or passive safety functions. Thus, although these contacts are '

associated with a safety related circuit, they were determined to not require testing to satisfy Technical Specification requirements.

JUSTIFICATION FOR SCHEDULE CHANGE The scope of work for the SRCTA project is larger than that indicated in our response to the subject violation (ref.1). In reference I we indicated that only those contacts which perform a function identified in the Technical Specifications would be reviewe 1. As indicated above, the scope of work for the SRCTA project also includes the review of contacts which perform a function identified in the  !'

UFSAR or GE system design specifications. In addition, eliminating those systems which do not perform any Technical Specification function from the  ;

project would not significantly reduce the scope of work because over 90% of the  !

systems under review perform at least one Technical Specification function.

Due to a shortage of station resources and allocation to higher priority issues, the work on this project was temporarily halted from October,1994, to February, 1995.

Extending the schedule from May 31,1995, to November 1,1995, will not decrease the reliability or safety of the facility because the system reviews completed to >

date indicate that a very high percentage of safety related contacts are being adequately tested. All safety significant systems including the Emergency Core Cooling Systems (FsCCS) have been reviewed, and untested functions identified.

In addition, no safety significant problems have been found as a result of the additional testing described in the previous section. The only remaining systems to be reviewed by NUS are non-safety related systems with safety-related components and regulatory-related systems.

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