IR 05000483/1990008
| ML20043D148 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 05/31/1990 |
| From: | Hague R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML20043D144 | List: |
| References | |
| 50-483-90-08, 50-483-90-8, NUDOCS 9006070176 | |
| Download: ML20043D148 (9) | |
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U.S. NUCLEAR REGULATORY COMMISSION
REGION III
Report No. 50-483/90008(DRP)
Docket No. 50-483 License No. NPF-30 Licensee: Union Electric Company Post Office Box 149 - Mail Code 400 St. Louis, MO 63166 Facility Name: Callaway Plant, Unit 1
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Inspection at: Callaway Site, Steedman, Missouri Inspection Conducted: April 1 through May 15, 1990 Inspectors:
B. H. Little B. L. Bartle'.t
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C. H. B r a-H ue, Chief Md Approved By: Jiefiar ' Ly Reactdefrojects Section 3C Date'
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Inspection Summary Inspection from April 1 through May 15. 1990 (Report No. 50-483/90008(ORP))
Areas Inspected: A routine unannounced safety inspection of non-routine
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events, plant operations, and maintenance and surveillance was performed.
Results: One violation was identified, failure to perform a technical specification (T/S) surveillance (local leak rate test) within the allowable
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time limit.
The violation met the test of 10 CFR 2, Appendix C, Section V.G.1; accordingly, no Notice of Violation was issued.
Other results included: The operating crew demonstrated a well executed, disciplined performance in response to an unplanned reactor trip.
Some equipment problems were experienced during plant restart following the trip (Paragraph 3.a).
Good work practices, supervision, engineering, and technical support were demonstrated during trouble shooting, surveillance, and maintenance activities (Paragraph 4).
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9006070176 900531 PDR ADOCK 05000483 Q
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DETAILS
1.
Persons Contacted D. F. Schnell, Senior Vice President, Nuclear
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- G. L. Randolph, General Manager, Nuclear Operations
- J. D. Blosser, Manager, Callaway Plant C. D. Naslund, Manager, Operations Support
- J. V. Laux, Manager, Quality Assurance
- J. R. Peevy, Assistant Manager, Operations and Maintenance W. R. Campbell, Manager, Nuclear Engineering M. E. Taylor, Assistant Manager, Work Control
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D. E. Young, Superintendent, Operations R. R.
-..,selius, Superintendent, Health Physics
- T. P. Sharkey, Supervising Engineer, Site Licensing
- G. J. Czeschin, Superintendent, Planning and Scheduling G. R. Pendegraff, Superintendent, Security L. H. Kanuckel, Supervisr,r, Quality Assurance Program G. A. Hughes, Superviso, Independent Safety Engineer Group
- J. C. Gearhart, Superirtendent, Operations Support, Quality Assurance
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- C..S. Petzel, Quality Assurance Engineer J. A. McGraw, Superintindent, Design Control
- Denotes those present a one or more exit interviews.
In addition, a number of equipment operators, reactor operators, senior reactor operators, and other members of the quality control, operations, maintenance, health physics, and engineering staffs were contacted.
2.
Inspection of Licensee Event Reports (92700)
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Through direct observations, discussions with licensee personnel, and a review of records, the following licensee event reports were reviewed to determine that reportability requirements were fulfilled, that immediate corrective action was accomplished, and that r.orrective action to prevent recurrence was accomplished in accordance with T/Ss.
The LERs listed below are considered closed.
a.
(Closed) LER 90001:
Failure to perform a local leak rate test or, an electrical penetration within the specified frequency.
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Background On January A. J.990, during a periodic review of upcoming scheduled surveillances, the surveillance scheduling engineer discovered that
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the 24 month, T/S required, Local Leak Rate Test (LLRT) surveillance for containment electrical penetration ZSE250 had not been performed since September 17, 1987.
The plant was in Mode 1 - Power Operation,100 percent reactor power at the time of discovery. The
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control room declared containment integrity inoperable and a one
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hour action statement from T/S 3.6.1.1 was entered.
The surveillance was completed in approximately 30 minutes satisfying T/S operability requirements.
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Licensee's Evaluation of Root Cause and Corrective Action The root cause of the event was a performance error during a manual
adjustment of the computerized schedule in September 1987 when a previous surveillance scheduling engineer incorrectly applied a 25 percent extension for the late finish date.
The licensee's corrective actions included a review of all currently scheduled Type B and C LLRT surveillance tasks to ensure there were no other problems and to check to ensure future due dates and late
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finish dates were within the proper time interval.
The review, completed on January 15, 1990, did not identify any additional problems with future due dates or late finish dates.
In addition,
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plant procedure PDP-ZZ-00009 (Surveillance Requirement Tracking Procedures) was revised, adding a requirement for independent verification of changes to the surveillance scheduling program.
Inspector's Review Throngh discussions with licensee personnel, a review of the event report, and associated reports, e.g., the incident report and the
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event review team report, the inspector determined that once
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identified the deficiency was appropriately documented, promptly corrected, and underwent a thorough cause evaluation. The licensee's corrective action appears adequate to prevent recurrence.
The performance error which incorrectly applied the 25 percent extension was an isolated occurrence.
While there were previous violations associated with surveillance activities none were attributed to the incorrect application of T/S 4.0.2.
The event posed no actual safety significance as demonstrated by the-satisfactory LLRT surveillance performed on January 8,1990.
The LLRT surveillance, T/S 4.6J 2.d, has a T/S required frequency of 24 months and T/S 4.0.2 doei dot apply.
The licensee's failure to perform the specified surveillance for the containment electrical penetration ZSE250 within 24 months of September 17, 1987 (last performed prior to January 8, 1990) is a violation of T/S 4.6.1.2.d (483/90008-01(DRP)).
The violation met the tests o' 10 CFR 2 Appendix C, Section V.G.1; consequently, no Notice >f Violation will be issued and this matter and LER 9001 are considered closed.
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b.
(Closed) LER 90002:
Electrical problem in the control rod system.
On February 2,1990 at 2:05 p.m. CST, a control rod urgent failure alarm was received during the performance of a monthly surveillance on movable controT rod assemblies.
The failure was determined by utility Instrument and Control (I&C) department personnel to be electrical, not mechanical, and the control rods were capable of
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insertion into the core upon a reactor trip signal. The control rods were declared inoperable by the licensed Shift Supervisor and T/S 3.1.3.1 Action Statement (b) was entered.
This T/S
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Action Statement states:
"With more than one full-length rod inoperable... be in HOT STANDBY within six hours."
To preclude an avoidable plant transient the licensee requested a Temporary Waiver of Compliance at 4:30 p.m. on February 2, 1990.
The control rod system was repaired and determined to be operable by
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T/S surveillance testing.
The T/S 3.1.3.1 Limiting Condition of f
Operation was satisfied at 9:22 a.m. on February 3,1990.
Licensee's Evaluation of Root Cause and Corrective Actions Root Cause The I&C departmert troubleshooting revealed one circuit card with a defective chip.
This card was an electronic counter circuit that is part of the slave cycler in the control rG logic cabinet.
Corrective Actions (1) The defective slave cycler counter card was replaced. An evaluation of slave cycler counter card history at Callaway indicated that this was the only failure since a modification
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installed additional cooling to the rod drive set room in l
June 1987.
The licensee concluded this event was a random i
failure and no further action will be taken.
(2) Operating License Amendment Number 51 to T/S 3/4.1.3 was implemented on March 1, 1990.
This amendment allows 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to troubleshoot and repair this type of failure.
Inspector's' Review
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The inspector observed the licensee's response to the event and participated in NRC/ Licensee discussions relating to the Temporary Waiver of Compliance.
The licensee made initial preparations for
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plant shutdown in the event the waiver request was denied.
The
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NRC granted the Temporary Waiver (within the six hour action
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requirement) extending the allowed control rod outage to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
3.
Plant Operations (71707)
a.
Operational Safety Verification Inspections were routinely performed to ensure that the licensee i
conducts activities at the facility safely and in conformance with regulatory requirements.
The inspections focused on the implementation and overall effectiveness of the licensee's control of operating acti'v'ities, and on the performance of licensed and i
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r non-licensed operators and shift technical advisors. The inspections included direct observation of activitiet,, tours of the facility, interviews and discussions with licensee personnel, independent verification of safety system status and luiting conditions of operation (LCO), and reviews of facility procedures, records, and repens. The following items were considered during these insper'.;ons:
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Adequacy of plant staffing and supervision.
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Control room professionalism, including procedure adherence,
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operator attentiveness, and response to alarms, events, and off-normal conditions.
Operability of selected safety-related systems, including
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attendant alarms, instrumentation, and controls.
Maintenance of quality records and reports.
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The inspectors observed that control room supervisors, shift technical advisors, and operators were attentive to plant conditions, performed frequent panel walkdowns and were responsive to off-normal alarms and conditions.
On May 1, 1990 at 1:31 p.m. CDT a reactor trip occurred.
At 1:28 p.m. CDT an I&C technician was replacing a main turbine stator
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cooling water conductivity cell when an unplanned short occurred.
The short caused high conductivity, loss of cooling water flow, and high temperature ularms to be indicated.
These alarms caused a turbine runback to occur. Three minutes later the turbine automatically tripped as designed.
Since the reactor power was
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still greater than 50 percent (P-9), a reactor trip also occurred.
The resident inspectors were on site and responded to the control room following the trip. The
- ing crew's performance during the trip response was professio.i ell executed and demonstrated a disciplined use of procedures.
swing the trip, operators
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attempted to close the main steam isolation valves (MSIV) to prevent on excessive cooldown.
During this attempt the "B" MSIV did not fully close on a manual yellow train actuation.
Upon using the red train actuation the MSIV fully closed. The licensee determined
that the yellow train accumulator was not adequately charged due to a failure of the nitrogen regulator. The nitrogen / hydraulic accumulator was techarged and the accumulators to all other MSIVs were verified operable.
The licensee later determined the cause of the short was a shall particle between a plastic cover and the power leads.
The conductivity cell was repaired and returned to service.
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The licensee was delayed in restarting the unit due to various equipment problems.
These included recalibration of the source range detectors, replacing a power supply card in one of the loop 3 reactor coolant system flow transmitters and other minor maintenance.
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On May 3, 1990 the inspectors were observing the restart of the unit.
Shortly after the control banks were starting to be withdrawn a reactor coolant system wide range temperature channel failed low.
The licensee was observed to respond conservatively to the failed channel by stopping the return to criticality and reinserting the control banks. The restart was continued after the channel was
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repaired.
Using licensee procedure 0$P-SF-00001, Revision 7, " Shutdown Margin Calculation" and 0$P-SF-00005, Revision 3. " Estimated Critical Position Calculation" the NRC inspectors performed manual
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calculations and compared them to the licensee's computer calculations. The answers agreed to within acceptable error margins.
On April 24,1990 at 12:51 p.m. CDT the licensee was measuring the output voltage of safety-related battery charger NK-24 when an over-voltage condition occurred. The charger had previously exhibited momentary voltage spikes and readings were being taken in preparation for the replacement of three cards. The over voltage condition was annunciated in the control room and resulted in loss of the 48 VOC power supply to SA075B.
This meant that the yellow train actuation to the MSIV and main feedwater isolation valves was
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The licensee entered T/S action 3.3.2, Action C which required that SA075B be restored or the unit be shutdown within six hours.
I&C technicians were summoned, drawings studied and procedures reviewed in order to determine the necessary repair steps.
The licensee reset the over-voltage circuit,'SA075B was restored to service and T/S 3.3.2, Action C exited well within the required time frame. The inspectors observed all aspects of the
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over-voltage condition and resulting repair efforts.
Even though they were only four days away from exceeding the continuous run
record of a sister plant, the licensee was observed to respond to this equipment failure in a professional, methodical, and conservative manner, b.
Off-shift Inspection of Control Room i
The inspectors performed routine inspections of the control room
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during off-shift and weekend periods; these included inspections between the hours of 10:00 p.m. and 5:00 a.m.
The inspections were conduct.ed to assess overall crew performance and, specifically, control room operator attentiveness during night shif ts.
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On Saturday, April 21, 1990, during a routine system walkdown the inspector observed a line cross-tying Train "A" and "B" of the Essential Service Water System (system designator EF).
The line had an open isolation valve and connected the pre-lube storage tanks.
The system engineer informed the inspector that the pre-lube storage tanks were a support system n_ot required for operability.
In addition, any active or passive failure of this line would not affect either traYn of EF.
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t The inspectors determined that both licensed and non-licensed operators were attentive to their duties, and that the administrative controls relating to the conduct of operation were being adhered to.
c.
Plant Material Conditions / Housekeeping
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The inspectors performed routine plant tours to asseis material conditions within the plant, ongoing quality activities and plantwide housekeeping.
The inspectors also accompanied the licensee's management on monthly plant tours.
Material conditions within the plant remained good. Minor deficiencies observed by the inspectors were discussed with the shift supervisor and were promptly corrected.
All activities were condrcted in an adequate and safe manner.
4.
Maintenance / Surveillance (62703) (61726)
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Selected portions of the plant surveillance, test and maintenance activities on safety-related systems and components were observed or reviewed to ascertain that the activities were performed in accordance with approved procedures, regulatory guides, industry codes and standards, and the Technical Specifications.
The following items were considered during these inspections:
the limiting conditions for operation were met while components or systems were removed from service; approvals were obtained prior to initiating the work; activities were accomplished using approved procedures and were inspected as applicable; functional testing and/or calibration was performed prior to returning the components or systems to service; parts and materfals that were used were properly certified; and appropriate fire prevention, radiological, and housekeeping conditions were maintained.
The observed ongoing maintenance and surveillance activities were found to be properly authorized and were being performed using approved procedures.
The activities were noted to be scheduled ar.d required isolations and tagging were found to be correctly carried out.
The limiting conditions for operation were adhered to during the performance of these activities.
In general, good workmanship and work practices were demonstrated.
a.
Maintenance The reviewed maintenance activities included:
Work Request No.
Activity W474427 Battery charger NK-24 intermittent undervoltage.
W129099 Safety injection pump "B" re-torque bolts to stop minor cooling water leak.
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Work Request No.
Activity W130873 Control room air conditioner, Unit A - clean out plugged drain lines.
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W132223 Ultrasonic test pipe wall thickness
"feedwater heaters" piping, EDP-ZZ-01115.
W128225 and Halon tank pressure check.
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W130493 Support engineering testing of pressurizer
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backup heater.
P470252 Lubricate turbine driven mechanical trip / throttle hand control valve (FCHV0312).
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During the performance of W474427 an inadvertent ground was
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introduced. This ground caused the "B" train actuation to the main
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steam isolation valves to become inoperable.
Further discussion of this event is in Paragraph 3.
b.
Surveillance The reviewed surveillances included:
Procedure No.
Activity ISF-AB-OP526 Functional - test; steam generator "B" steam
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line pressure ACOT.
ISF-SE-ON42B Functional - nuclear; nuclear instrument power range N-42 low setpoint.
ISL-GS-00A2B Containment hydrogen concentration analysis indicator.
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ETP-BB-00039 Engineering reactor ves.- ) level indication system data, t
OSP-SF-00002 Control rod movement test.
ISF-AE-0L554 Steam Generator "D" protection "A" level
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transmitter.
Activities relating to troubleshooting, repair and surveillances associated with; the rod control failure, stator cooling monitor and the battery charger, were well supervised and effectively supported by engineering and technical support o oups.
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All activities were conducted in an adequate and safe manner.
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5.
Violations for Which a " Notice of Violation" Will Not be Issued The NRC uses the Notice of Violation as a standard method for forralizing the existence of a violation of a legally binding requirement. However, because the NRC wants to encourage and support licensee initiatives for self-identification and correction of problems, the NRC will not generally issue a Notice of Violation for a violation that meets the tests of 10 CFR 2, Appendix C, Section V.G.I.
These tests are: (1) the violation was identified by the licensee; (2) the violation would be J
categorized as Severity Level IV or V; (3) the violation was reported to the NRC, if required; (4) the violation will be corrected, including measures to prevent recurrence, within a reasonable time period; and (5) it was not a violation that could reasonably be expected to have been prevented by the licensev's corrective action for a previous violation.
Violations for which a Notice of Violation will not be issued are identified in Paragraphs 2.a and 2.b of this report.
6.
Exit Meeting (30703)
The inspectors met with licensee representatives (denoted under Persons Contacted) at intervals during the inspection period. The inspectors j
summarized the scope and findings of the inspection.
The licensee
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representatives acknowledged the findings as reported herein. The inspectors also discussed the likely informational content of the
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inspection report with regard to documents or processes reviewed by the inspectors during the inspection.
The licensee did not identify any such documents / processes as proprietary.
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