IR 05000298/1998006
| ML20154R534 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 10/21/1998 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | |
| Shared Package | |
| ML20154R532 | List: |
| References | |
| 50-298-98-06, 50-298-98-6, NUDOCS 9810270064 | |
| Download: ML20154R534 (13) | |
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ENCLOSURE U.S. NUCLEAR REGULATORY COMMISSION
REGION IV
Docket No.:
50-298 License No.: -
DPR 46 Report No.:
50-298/98-06 Licensee:
Nebraska Public Power District Facility:
Cooper Nuclear Station
. Location:
P.O. Box 98 Brownville, Nebraska Dates:
August 23 through October 3,1998 Inspectors:
M. Miller, Senior Resident inspector V. Gaddy, Acting Senior Resident inspector C. Skinner, Resident inspector K. Weaver, Resident inspector Approved By:
C. Marschall, Chief, Branch C Division of Reactor Projects
. ATTACHMENT:
Supplemental Information 9810270064 981021 PDR ADOCK 05000298
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EXECUTIVE SUMMARY Cooper Nuclear Station NRC Inspection Report 50-298/98-06 l
Operations Routine operational activities during the inspection period were generally good l-
(Section 01.1).
The development and review of the specialinstructions for securing Reactor Feedwater
Pump A for troubleshooting the speed control system was very thorough. The l
instructions were reviewed by the operators, performed on the simulator, and approved by the Station Operations Review Committee. Operators performed the special instructions in a well controlled manner with appropriate oversight by the senior licensed reactor operators (Section O2.1).
Inspectors identified that operations issued a nonconservative standing order, which
listed the incorrect temperature (92'T verses 91 *F) at which the reactor equipment cooling system would become inoperable (Section O3.1).
A station operator exhibited good knowledge of plant operation during a walkdown of the
reactor building. The station operator was familiar with the operation of prestaged equipment required to be used in an emergency situation (Section 04.1).
Maintenance j
Overall, the maintenance activities observed were well-controlled and performed in a
step-by-step manner (Section M1.1).
The inspectors observed several examples of degraded material equipment which were
corrected by the license. Overall plant material condition was good (Section 2.1).
The licensee isolated the cause of the failure of the reactor building exhaust isolation
valves to the solenoid operator, but have not determined the root cause. The licensee's corrective actions appeared to bound the potential causes to prevent another failure until the root cause can be determined and corrected (Section M2.2).
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P' ant Support l
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- Radiation protection were observed performing their duties in accordance with
management expectations and in accordance with the plant procedures. Good support was also provided to plant workers as needed (Section R1.1).
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R,_e_ port Detalls l
Summary of Plant Status
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l At the beginning of the inspection period, the plant was at 100 percent power. On August 29,
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l 1998, power was reduced to approximately 70 percent for turbine valve testing and was
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returned to 100 percent the next day. On September 7, power was reduced to approximately j
70 percent to remove a feedwater pump from service due to speed control problems. The plant was restored to 100 percent on September 9. On September 11, the plant began coasting
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l down in power and, on October 3, the licensee placed the plant in Mode 3 (hot shutdown) to begin the 18th refueling outage.
I. Operations
Conduct of Operations i
01.1 Control Room Crew Effectiveness
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a.
Inspection Scoce (71707)
The inspectors performed routine inspections of operatic,nal activities during the inspection period.
b.
Observations and Findinas During the inspection period, inspectors performed routine observations of operational activities. The inspectors observed that c,perating crews were focused on plant safety
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and maintained questioning attitudes. Information provided during shift turnovers was adequate to ensure safe plant operations. Logkeeping was thorough enough to provide
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relevant plant conditions and indications. Annunciator response and acknowledgment I
was good and the use of three-way communication was good.
c.
Conclusions l
Routine operational activities during the inspection period were generally good.
Operational Status of Facilities and Equipment 02.1 Reactor Feedwater Pumo A Speed Control Problem a.
insocction Scope (71707)
The inspectors reviewed special instructions associated with securing Reacter Feedwater Pump A and observed operators during the performance of these special instructions. Discussions were held with operators and management.
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Observations and Findinas On September 7,1998, the operators identified that Reactor Feedwater Pump A speed controller would not respond in the control room.
Special instructions for securing the reactor feedwater pump were developed with contingency actions. The special instructions were reviewed by the control room operators, performed on the simulator, and approved by the Station Operation Review Committee. Recommendations were incorporated into the special instructions after each review step.
The inspectors attended the prejob brief and observed the operators' performance of the specialinstructions. The inspectors questioned how the operators were to reduce reactor power, since neither the special instructions nor the briefing addressed this question. The shift supervisor stated that reactor power was to be reduced by lowering core flow, and an earlier briefing addmssed this question. The special instructions were performed in a controlled manner, with appropriate oversight by senior licensed reactor operators.
The speed control system was corrected and the reactor feedwater pump was returned to service on September 8.
c.
Conclusions The development and review of the special instructions for securing Reactor Feedwater Pump A for troubleshooting the speed control system was very thorough. The instructions were reviewed by the operators, performed on the simulator, and approved by the rhtien Operations Review Committee. Operators performed the special instructions in a well controlled manner with appropriate oversight by the senior licensed reactor operators.
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Operations Procedures and Documentation O3.1 Nonconservative Standina Order a.
l.rl.soection Scoce (71707)
The inspectors reviewed five current standing orders and held discussions with operators and engineers.
b.
Observations and Findinas On September 16,1998, inspectors identified that Standing Order 98-027, issued September 11, was nonconservative. Through discussions with engineering, the inspectors determined that 91 *F was the temperature where the reactor equipment cooling system was inoperable. The standing order stated that 92*F was the temperature limi.
3-In response to the inspectors' questions, Standing Order 98-028 was issued, on September 16, that reflected the 91 *F temperature limit. The licensee documented this issue on a problem identification report. At the close of the inspection period, the j
licensee had not completed reviews to determine whether operators had relied on the incorrect value of the standing order.
The other four standing orders reviewed were appropriate and no other problems were identified.
c.
Conclusions Inspectors identified that operations issued a nonconservative standing order, which listed the incorrect temperature at which the reactor equipment cooling system would
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become inoperable.
Operator Knowledge and Performance 04.1 Nonlicensed Operator Performance a.
Insoection Scope (71707)
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The inspectors observed a station operator perform his duties during a tour of the reactor building, b.
Observations and Findinas On September 25,1998, the inspectors accompanied the station operator on a tour of the reactor building. The purpose of the tour was to observe the station operator perform a plant walkdown and to status plant equipment. Prior to the tour, the inspectors reviewed Procedure 2.1.11, " Station Operators Tours." The inspectors noted that the station operator conducted the plant walkdown in accordance with the requirements of the procedure. The station operator also exhibited good knowledge of plant operations and was aware of the purpose of various prestaged emergency equipment.
During the tour, the inspectors noted that housekeeping was good, with one exception.
Housekeeping under the torus needed to be improved. The station operator indicated that he had observed the housekeeping deficiencies during an earlier plant tour and had informed the appropriate personnel, c.
Conclusions A station operator exhibited good knowledge of plant operation during a walkdown of the reactor building. The station operator was familiar with the operation of prestaged equipment required to be used in an emergency situation.
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Miscellaneous Operations issues 08.1 (Closed) Violation 50-298/97006-01: Failure to follow Technical Specifications and
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l inadequate procedure for re inerting primary containment. This violation consisted of two examples of inadequate procedures. In the first example, a procedure did not allow the use of installed 24-inch valves for inerting the primary containment. In the second
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example, a procedure allowed operators to place the mode switch in the startup/ hot standby position prior to performing the daily jet pump operability check contrarv to the Technical Specifications. This review only addressed the first example associated with the use of 24-inch valves for inserting the drywell. The second example was closed in NRC Inspection Report 50-298/98-02.
l The inspectors verified the corrective actions described in the licensee's response letter, l
dated August 25,1997, to be reasonable and complete. No similar problems were identified.
08.2 _ (Closed) Licensee Event Report 50-298/97008: Technical Specification 3.7.A.5.d time l
limit was exceeded. Technical Specification 3.7.A.5.d required that oxygen
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concentration be reduced to less than 4 percent within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or the reactor must be shutdown. The licensee requested enforcement discretion for this Technical Specification, which was granted by the NRC.
The inspectors verified that the licensee's corrective action have been completed; therefore, this licensee event report is closed.
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11. Maintenance M1 Conduct of Maintenance M1.1 General Comments a.
Inspection Scope (61726 and 62707)
Inspectors reviewed work packages and held discussions with maintenance craft, operations, and management.
b.
Observations and Findinas inspectors observed the following maintenance activities:
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Maintenance Work Request 98-2439 Repair leaking diesel generator starting air i
pressure relief valve l
Maintenance Work Request 98-2748 Disassemble, inspection, and rebuild of reactor building basement sump pump i
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l Surveillance Procedure 6.RCIC.302 Reactor core isolation cooling pump law discharge flow channel calibration Surveillance Procedure 6.1DG.101 Diesel generator 31 day operability test The inspectors observed that the work activities were well controlled and work
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instructions were performed as written.
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Conclusions Overall,' the maintenance activities observed were well controlled and perfc med in a step-by step manner.
M2 Maintenance and Material Condition of Facilities and Equipment i
M2.1 Material Condition a.
Insoection Scoce (62707)
Inspectors performed plant walkdowns, observed maintenance, and reviewed a sample
. of maintenance activity records, inspectors held discussions with various licensee staff and management.
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Observations and Findinaq Inspectors assessed plant material conditions during the course of the inspection period.
Overall, plant material condition was good with the exception of the following examples.
Reactor Building Exhaust Isolation Valves HV-AOV-259AV and 261 AV failed
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surveillance testing requirements. The licensee increased the testing frequency o
from monthly to weekly and planned to replace the solenoid operator every
. 6 months until the cause of the failure can be determined.
Reactor Feedwater Pump A speed control problems.
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Diesel generator air system pressure relief valve seal failed and resulted in an
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inoperable diesel generator.
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i One of two sump pumps in the Core Spray Pump B room would not operate.
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Conclusions The inspectors observed several examples of degraded material equipment that were s
corrected by the license. Overall, plant material condition remained good.
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M2.2 Reactor Buildina Isolation Valves Failed Surveillance Test
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a.
Inspection Scope (62707)
The inspectors followed the licensee's activities associated with the failure of the reactor building isolation valves. Discussions were held with operations, engineering, and management.
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Observation and Findinas
' On September 16,1998, both Reactor Building Exhaust isolation Valves HV-AOV-259AV and -261 AV failed surveillance testing requirements.
Troubleshooting activities isolated tho failure mechanism to the solenoid operator. The licensee checked for binding and interference in the stroking of the valve and checked
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the air filters for contaminates; no problems were identified. The licensee concluded that the solenoid operator was being used in an appropriate application, and there was no foreign material in the air supply tubing or air supply filters. The licensee's evaluation has not ruled out a chemical interaction between a contaminant and the manufacturer's lubricant or an expansion or swelling of internal components. At the end of the inspection period, the licensee was still working on the root cause.
As corrective actions the licensee replaced both solenoid operators, increased the testing frequency from monthly to weekly, and implemented a preventive maintenance task to replace the solenoid operator every 6 weeks. These actions will continue until the cause of the failure can be determined. Based on past history, the inspectors concluded that these actions were appropriate.
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An inspector followup item will be opened to review the licensee's evaluation for the repeated failures of the reactor building ventilation isolation valves (50-298/98006-01).
c.
Conclusions ~
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The licensee isolated the cause of the failure of the reactor building exhaust isolation i
valves to the solenoid operator, but have not determined the root cause. The licensee's corrective actions appeared to bound the potential causes to prevent another failure until the root cause can be determined and corrected.
M8 Miscellaneous Maintenance issues (92902)
M8.1 (Closed) Licensee Event Report 50-298/97005: Inadvertent start of Diesel Generator 1.
' An inadvertent slow start of the diesel generator during performance of Surveillance Procedure 6.1DG.302, "Undervoltage Logic Functional, Load Shedding and Sequential Loading Test." The licensee determined the start of the diesel generator was due to human factors deficiencies in the procedure. The procedure required installation of a
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jumper in a congested and not readily accessible area in the diesel generator control cabinet. Although the procedure had been used successfully in the past, a different type of jumper which had larger jaws was being utilized. During the installation of the jumper,
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7-an electrician inadvertently touched the wrong terminal. This resulted in the completion of the slow start circuit and subsequently started the diesel generator.
The licensee's corrective actions included performing a procedure change to relocate the jumper installation point to a more readily accessible terminal in the cabinet.
Subsequently, Procedure 6.1DG.302 was successfully performed. The licensee had performed an evaluation and planned to install permanent test jacks on the effected relays during Refueling Outage 18.
Ill. Enaineerina E2 Engineering Support of Facilities and Equipment E2.1 Reactor Eauloment Coolina System Instrument Uncertainty a.
Insoection Scoce (37551)
The inspectors followed the licensee's actions in determining instrument uncertainty for the reactor equipment cooling system outlet temperature. Discussions were held with operations and engineering personnel.
b.
Observation and Findinas From July 24 until September 11,1998, engineering personnel provided nonconservative information to the control room regarding the operability of an essential system.
On July 24, engineering provided operations with the results (+/- 2.058 F) of an interim calculation on instrument uncertainty for the reactor equipment cooling system temperature until a formal calculation was completed. Based on this interim calculation, operations management issued Standing Order 98-021 which informed control room
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operators that at 93*F the reactor. equipment cooling system becomes inoperable and the plant must be shut down. The inspectors questioned engineering personnel about
. round off" and the correct number of significant digits. Based on the questions,
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engineering personnel revised the standing order to 92*F.
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' On August 23, Standing Order 98-024 was issued which stated that 93*F was the temperature limit for the reactor equipment cooling system. Then on September 11, engineering personnel provided a formal calculation to the control room that concluded I
Instrument uncertainty was +/- 3.16*F.
At the end of the inspection report period, engineering was reviewing whether the reactor equipment cooling system was operated outside the design basis (adding the correction factor for instrument uncertainty). The inspectors will track the review of this evaluation on past operability by an inspector followup item (50-298/98006-02).
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Conclusions-The inspectors identified that nonconservative information was provided to the control l
room by engineering personnel on the reactor equipment cooling system temperature.
instrument uncertainty of the temperature indicator was calculated to be +/-2.058*F and i
over a month later engineering performed a formal calculation which determined instrument uncertainty to be +/-3.16*F.
E8 Miscellaneous Engineering lasues
E8.1 (Closed) Insoector Followuo item 50-298/98004-06:' Replacement component evaluations failed to address test equipment. Inspector Followup Item 50-298/98005 03 already tracked this item; therefore, the inspector followup item is closed and the results of followup inspections will be tracked by inspector Followup item 50-298/98005-03.
E8.2 (Closed) Violation 50-298/96030-02: Failure to comply with 10 CFR 50.59 - residual
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heat removal system not required to be available during full core offloads. This violation consisted of the licensee's failure to ensure that Residual Heat Removal Train B was available to assist the fuel pool cooling system during full core offloads or to perform a 10 CFR 50.59 evaluation that demonstrated the Residual Heat Removal Train B was not needed to be available.
The inspectors verified the corrective actions described in the licensee's response letter, dated January 20,1997, to be reasonable and complete. No similar problems were identified.
IV. Plant Support -
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' Radiological Protection and Chemistry Controls R1.1. Radiation Protection Personnel Performance a.
Inspection Scoce (71750)
L The inspectors assessed the performance of radiation protection personnel during plant tours, b.
Observations and Findinas During this inspection period, the inspectors made frequent tours of the radiologically controlled area. Radiation protection personnel were observed working in accordance with requirements of management expectations and plant procedures. Radiation
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l protection personnel also provided good support to plant workers as needed. Surveys performed by radiation protection personnel were conducted in accordance with plant
procedures.
On September 29,1998, the inspectors observed the support provided by radiation
. protection personnel to a maintenance mechanic during the disassembly, inspection, i
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and rebuild of the reactor building basement sump pump located in the southeast l
. uadrant. The work was performed in a highly contaminated area. The radiation q
protection technician performed frequent surveys of the work area, surveyed equipment
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L-as it was disassembled, and ensured that the maintenance mechanic performed work in
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accordance with the requirements of the radiation work permit.
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Conclusions
. Radiation protection personnel were observed performing their duties in accordance with management expectations and in accordance with the plant procedures. Good support was also provided to plant workers as needed.
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. Exit Meeting Summary The inspectors presented the inspection results to members of licensee management at the exit
meeting on October 6,1998. The licensee acknowledged the findings presented.
The inspectors asked the licensee whether any materials examined during the inspection should be considered propr:etary. No proprietary information was identified.
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l ATTACHMENT PARTIAL LIST OF PERSONS CONTACTED Licensee M. Boyce, Plant Engineering Manager P. Caudill, General Manager, Technical Services L. Dewhirst, Licensing Engineer C. Gaines, Maintenance Manager.'
B. Houston, Licensing Manager T. Kissam, Diesel Generator System Engineer 4 D. Kunsemiller, Licensing Consultant.
M. Peckham, Plant Manager.
J. Peters, Licensing Secretary B. Rash,' Senior Engineering Manager
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A. Shiever, Operations Manager '
- J. Sumpter, Licensing Supervisor
.NRC T. Meado.vs, NRC Examiner
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. INSPECTION PROCEDURES USED IP 37551: One te Engineering i
IP 61726:' Surveillance Observation IP 62707:. Maintenance Observation o
,IP 71707f Plant Operations
' IP 71750: Plant Support Activities IP 92901i Followup - Plant Operations
- IP 92902: Followup - Maintenance
- IP 92903
- Followup - Engineering IP 92700: Licensee Event Report - Onsite Review
IP 93702: Onsite Response -
' ITEMS OPENED, CLOSED, AND DISCUSSED Opened 1
= 50-298/98006-01.
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~ Review licensee's evaluation for the repeated failures of the reactor building ventilation isolation valves (Section M2.2).
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'50-298/98006-02 IFl Review past operability of the reactor equipment cooling system taking
' instrument uncertainty into account (Section E2.1).
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Closed
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50-298/97006-01 VIO Failure to follow Technical Specification and' inadequate procedure for re-inerting primary containment (Section 08.1).
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50 298/97008'
LER Technical Specification 3.7.A.5.d time limit was exceeded (Section 08.2).
50-298/97005 LER Inadvertent start of Diesel Generator 1 (Section M8.1).
- 50-298/98004-06 IFl Replacement component evaluations failed to address test equipment (Section E8.1).
-50-298/96030-02 VIO Failure to comply with 10 CFR 50.59 - residual heat removal system not required to be available during full core offloads (Section E8.2)
Discussed 50-298/98005-03 IFl Failure to specify testing requirements for replacement relays (Section E8.1).
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