ML18059A667
| ML18059A667 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 02/04/1994 |
| From: | Slade G CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9402170017 | |
| Download: ML18059A667 (7) | |
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\\l consumers Power POWERINli MICHlliAN"S PROliRESS Palisades Nuclear Plant:
27780 Blue Star Memorial Highway, Coven. Ml 49043 February 4,*1994 Nuclear Regulatory Commission Docu~ent Control Desk Wash{ngton., Dt 20555 GB Slade General Manager DOCKET 50-255 - LICENSE DPR PALISADES PLANT - REPLY TO NOTICE OF VIOLATION; NRC INSPECTION REPORT No. 93030 NRC Inspection Report No. 93030, dated December 23,* 1993 transmitted three apparerit.violations relating* to the excessive cooldown rate event of September 17, 1993.
The apparent v~6lations concerned:
(1) cooldown rate exceeded, (2) procedures not implemented as required and (3) procedures not appropriate to circumstances.
CPCo agrees ~ith the violations as stated.
The events leading to the violations, the root causes, and the corrective actions addressing the violations were summarized at the December 3, 1993 Enforcement Conference, and the excessive cooldown rate event was also the subject of Licensee Event Report (LER) 93010, dated October 18, 1993.
Our enclosed reply to the Notice of Violation is to a large extent a compilatiori of previously communicated information.
~:~~-
Gerald B Slade General Manager CC Administrator, Region Ill, USNRC NRC Resident Inspector - Palisades Attachment
.. 15 c :*: *:* ~.
9402170017 940204 PDR ADDCK 05000255 Q
iJ ATTACHMENT Consumers Power Company Palisades Plant Docket 50-255
. : REPLY TO NOTICE OF VIOLATION NRC INS~ECTION REPORT No. 93030 February 4; 1994
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5* Pages
REPLY TO NOTICE OF VIOLATION Violation A Technical Specification 3.1.2.a requires, in part, that the average heatup or cooldown rate limit in any one hour time period shall not exceed 40 degrees Fahrenheit per hour when Primary Coolant System (PCS) -temperature is greater than 170 degrees Fahrenheit and less than or equal to 250 degrees Fahrenheit, and the average heatup or cooldown rate limit shall not exceed 20 degrees Fahrenheit per hour when PCS temperature is less than or equal to 170 degrees Fahrenheit.*
- 1.
Contrary to the above, on September 17, 1993, from 1 :16 p.m. to 2: 16 p.m., with the primary coolant system temperature between 170 degrees fahrenheit and 250 degrees fahrenheit, the average cooldown rate was approximately 48 degrees fahrenheit per hour.
- 2.
Also contrary to the above, on September 17,.1993, from 1:51 p.m. to 2:51 p.m. with the shutdown cooling temperatilre less than 170 degrees fahrenheit, the average coo)down rate was approximately 49 degtees fahrenheit per hour.
Reason for the Violation The ~ause o( the violation was~ combination of personnel error and inadequate procedural guidance.
The licensed cont~ol operators directly respo~sible for controlling and monitoring Primary Coolant System (PCS) cooldown rate were aware of the limits for cooldown rate and recorded times and temperatures which ~hould have alerted them to the excessive cooldown rate; However, the operators failed to recognize and act on the informatibn.
The procedural guidance w~~ inadequate in several important re~pects. The procedure provide_d only general guidance as to the frequency of recording PCS cooldown information and to which instruments to utilize under varying circumstances during the cooldown.
The proced~re also failed to provide appropriate guidance for calculating the cooldown rate over the tran~ition period from forced flow with Primary Coolant Pumps (PCPs) in service to PCPs removed from servic~ with only the Shutdown Cooling System (SOC) in service.
Corrective Actions and Results Achieved A bounding engineering analysis was performed to evaluate the effects of the excessive PCS cooldown rate events of September 17, 1993, with respect to 10CFRSO, Appendix G, pressure and temperature limits.. The analysis concluded that while the allowed cooldown rates of 40°F per hour (250°F ~ PCS > 170°F) and 20°F per hour (170°F ~ PCS) respectively, were exceeded during the September 17, 1993 cooldown of the PCS, the 10CFRSO, Appendix G, limits 1
pertaihing to reactor vessel protection from brittle fracture were not Violated.
Corr~ctive*Action to Av6id Future Non~Compliance
- An engineering analysis was also performed tci evaluate the proper PCS temperature indicators to consider, relevant to calculating an appropriate cooldown rate over the.transition period from forced flow with PCPs in service to only the SOC system in service.
The analysis determined that Tc~d* at the time the PCPs were removed from service, should be used as the reference point and should be compared with the SOC system return temperature subsequent to termination of PCP flow.
Base._~ upon this information, the PCS coo 1 down which occurred on June 8, 1993 at the commencemerit of the refueling Qutage was reviewed as an example of a typical cooldown to asceitain the generi~ impact upon Appendix G limits. *It was concluded that Appendix G limits were n6t violated on the June 8, 1993 cooldown, even thougn the Technical Specifications cooldown rate limit of 20°F per hour was exceeded using this methodology.
Plant cooldowns, since the incorporation of the 20°F per hour limit with Amendment 131 to the Technical Specifications in 1990, are being evaluated, using the methodology described above,* to determine if the 20°F per hour limit had been ~xceeded on previous
,,. cooldown event_s.
An evaiuatirin of the existing Technical Specifications requirements for PCS heatup and coo 1 down rates wi 11 be performed* to determine if the 1 imi ts. are overly restrictive.* Appropriate actions to revis~ overly ~estrictive limits will be taken if warranted.
Classro~m and simulator trafning of op~rators h~s-been provid~d on the procedure changes and the met~odology corresponding to appropriate implementation of'the Te~hnic~J,Specifications requirements regarding PCS tooldown.
Date of Full Compliance:
Full compliance has been achieved.
Violation B.
Technical Specification 6.8.1.a requires, in part, that written procedures be established, -implemented, and maintained covering the appl.icable procedures recommended in Appendix A *of Regulatory Guide 1.33,_Revision 2 (February 1978), Quality Assurance Program Requirements, as endorsed by CPC-2A, Quality Program Description.
- 1.
Administrabve Procedure 4.00, "Operation Organization, Responsibilities, and Conduct," Revision 11, e_stablished to implement the procedure listed in Regulatory Guide 1.33, Appendix A,Section I.b,.
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~equires, in Step 4.8.1.i, that the contror operator ~emain alert* and knowledgeable of all pla~t operations in progress that involve the functioning_ of equipment contro77ed from the main control room, and anticipate potential problem areas.
Contrary to the above, on September *11, 1993, the control operators failed -to remain cognizadt of the cooldown rate, which *resulted in exceeding the associated Technical Specification limits.
- 2.
Administrative Procedure 4.00, "Operation Organization, Responsibilities, and Conduct," Revision 11, requires, in Step 4.4.1.n, that the shift supervisor shall review shift reports, shift logs, completed checklists, and other data compiled by the shift operating crew to detect abnormal trends, assess potential operating problems, and confirm ac~uracy of the information.
Contrary to the above, on September.*11, 1993, the shift _supervisor fwiled to review the PCS Cooldown Data log, ~hich restilted in the shift supervisor failing to remain cognizant of the cooldown rate of the
- primary coo 1 ant system.
'Reason for the Violation *.
The cause of the ~i6lation was th~ failure of the control operators to assume
- specific ~wnership for controlling and monitoring the PCS cooldown.
The*
.control* operators re~ognized their collectiv~ responsibility but failed.to
- appropriately coordinate the activity amohg themselves.
Therefore, some of the specific duties associated with th~ cooldown were not performed by either
- ~perator.
- Additionally~ the shift supervisor failed to adequately prioritize-available oversight resources, which resulted i~ all of the, shift supervision beirig involved in other activities. Consequently, none of the supervisory personnel remained sufficiently cognizant of the cobldown rate of the primary coolant syste~ which was in ~regress.
Corrective Actions *and Results Achieved The shift supervisor and involved control oper~tors were removed from licensed o~erator duties.
During this time, the crew was retrain~d in the specific
.tasks associated with-proper control and monitoring of a PCS cooldown and wit~
. generic tasks involving job planning, teamwork and communication skills. The crew was then evaluated on the control room simulator.
Results of the evaluation indicated suffic.ient competency to resume licensed operator duties.
Corrective Action to Avoid Future Non-Compliance The importance of data gathering has been stressed to all operations personnel with emphasis placed both upon obtaining thorough and accurate readings, and with the evaluation of the readings obtained.
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Man~ge~ent has discussed the implications of this event and similar past events involving personnel error with each operating crew, stressing attention to detail, use of the principles of self-checking, and t~e use of pre-job
-briefs to clearly identify individual roles when multiple individuals are lnvolved in a task.
The oversight responsibilities of the Shift Enginee~ (combined Shift Technical Advisor (STA) or second SRO)
~ill be re-evaluated for the purpose of clarifying and prioritizing the oversight duties of this position.
Field monitoring by management of activities in the plant and at the simulator are being conducted to ensure management expectations are being met.
Date of Full Compliance Full compliance has been achieved.
Violation C 10 CFR 50, Appendix 8, Criterion V, requires, in part, that actjvities affecting quality shall b~ prescribed by procedures appropriate to the circumstances.and sha 1]. be accomp 1 i shed in accordance with these procedures.
- 1.
Contrary to the above, System Operating Procedure (SOP)-1, "Primary Coolant System,"*Revision 25, was inappropriate to the circumstances in that ft did not require control operators to log shutdown cooling return temperature when the shutdown cooling system was in operation and a77 primary coolant pumps were secured.
- 2.
Also contrary to the above, SOP-1, "Primary Coolant System," Revision 25, was.inappropriate to the circumstances in that it did not consider the transitio!l of temperature monitoring from cold leg temperature to shutdown cooling return temperature, thus reflecting the temperature changes on the reactor vessel be~tline.
Reason for the Violation The cause of the.violation was an incomplete understanding of the Technical.
Specifications requirements regarding cooldown of the PCS with the PCPs
-secured.
While the applicable procedure specified that SOC return temperature was to be utilized when all the PCPs were secured with the SOC system in operation, the procedure failed to extend this requirement to the attachment provi-ded for logging PCS temperature.,_Additionally, the transition of temperature monitoring from PCS T ~d to SOC return temperature and its resultant reflection of the actua, temperature change at the reactor vessel b~ltline was not previously understood.
Cbnsequently, the procedure lacked*
specific detail in this area,* resulting in the practice of re-initializing the data using only SOC return temperature at the point of *transition from PCS Tc~d temperature to SOC return temperature.
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An und~rljing root cause for this violation is the inadequate implementation of Technical Specifications Amendment 131.
An evaluation of the technical specifications change process-has been initiated.
Corrective Actions and Results Achieved The applicable procedure, SOP-1, "Primary Coolant System," has been revised to.
provide specific guidance on controlling PCS cooldown rate throughout the transition period corresponding to the securing of an PCPs.
Included with this revision was an improved data table for logging important parameters associated with the cooldown.
Corrective Action to Avo~d Fuiur~ Non-Compliance An evaluation of the existing Technical Specifications requirements f6r PCS heatup and cooldown rates will be performed to determine if the limits are overly restricti~e. Appropriate ~ctions to revise overly restrictive limits will be taken if warranted.
Class~oom and ~imulator training of operators has been provided on the procedure changes and the methodology cor~esponding to appropriate impl~~entation of the Technical Specifications requirements regarding PCS cool down. -
As discussed in the Reason for the Violation, an evaluation of the technical specifications change process has been initiated.
Date of Full Compliance F~ll compliance has been achieved.
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