IR 05000269/1988015
| ML16127A201 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 07/21/1988 |
| From: | Peebles T, Skinner P, Wert L NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML16127A200 | List: |
| References | |
| 50-269-88-15, 50-270-88-15, 50-287-88-15, NUDOCS 8808040132 | |
| Download: ML16127A201 (13) | |
Text
S REG,.
UNITED STATES NUCLEAR REGULATORY COMMISSION
REGION II
o 101 MARIETTA STREET, ATLANTA, GEORGIA 30323 Report Nos.;
50-269/88-15, 50-270/88-15, 50-287/88-15 Licensee:
Duke Power Company 422 South Church Street Charlotte, Docket Nos.:
50-269, 50-270, 50-287 License No DPR-38, DPR-47, DPR-55 Facility Name:
Oconee Nuclear Station Inspection Conducted:
ay 17 -
July 15, 1988 Inspectors:
P.H Sinner Senio Resident Inspector ateS ate Approved by:1 ebles, Sect n Chief
,gat/Signed Division of React r Projects SUMMARY Scope:
This routine, announced inspection involved resident inspection on-site in the areas of operations, surveillance, maintenance, safeguards and radiation protection, inspection of open items, and Safety System Functional Inspection report followu Results:
Of the six areas inspected, no violations were identifie.,
9o721 88801 Or-050026 PD KGI
REPORT DETAILS
.1. Persons Contacted Licensee Employees
- M. Tuckman, Station Manager J. Davis, Technical Services Superintendent W. Foster, Maintenance Superintendent T. Glenn, Instrument and Electrical Support Engineer C. Harlin, Compliance Engineer D. Hubbard, Performance Engineer
- T. Matthews, Production Specialist J. McIntosh, Administrative Services Superintendent F. Owens, Assistant Engineer, Compliance R. Sweigart, Operations Superintendent L. Wilkie, Integrated Scheduling Superintendent Other licensee employees contacted included technicians, operators, mechanics, security force members, and staff engineer NRC Resident Inspectors
- P.H. Skinner
- L.D. Wert
- Attended exit intervie.
Licensee Action on Previous Enforcement Matters a. (Closed)
Violation (50-269,270,287/87-49-01):
Failure To Maintain Containment Isolation During Refueling Operatio The licensee responded to this violation in correspondence dated January 28, 198 The corrective actions addressed in this response were implemented and have been reviewed by the inspector. Based on this review, this item is close. Plant Operations (71707)
a. The inspectors reviewed plant operations throughout the reporting period to verify conformance with regulatory requirements, technical specifications (TS), and administrative controls. Control room logs, shift turnover records, and equipment removal and restoration records were reviewed routinel Discussions were conducted with plant operations, maintenance, chemistry, health physics, instrument and electrical (I&E), and performance personne Activities within the control rooms were monitored on an almost daily basis. Inspections were conducted on day and on night shifts, during weekdays and on weekend Some inspections were made during shift change in order to evaluate shift turnover performanc Actions observed were conducted as required by the licensee's administrative procedure The complement of licensed personnel on each shift inspected met or exceeded the requirements of T Operators were responsive to plant annunciator alarms and were cognizant of plant condition Plant tours were taken throughout the reporting period on a routine basis. The areas toured included the following:
Turbine Building Auxiliary Building Units 1,2, and 3 Electrical Equipment Rooms Units 1,2, and 3 Cable Spreading Rooms Station Yard Zone within the Protected Area Standby Shutdown Facility Units 1,2 Penetration Rooms During the plant tours, ongoing activities, housekeeping, security, equipment status, and radiation control practices were observe Unit 1*-
Unit 1 started this reporting period operating at 100%
power until June 29, when due to a low oil level on 1B2 Reactor Coolant Pump (RCP),
power was reduced to 72%.
Power was reduced to 24% on July 1, oil added to 1B2 RCP and power returned to 100% on July On July 6, the unit tripped from 100% power when a technician caused a transient on the integrated control syste Power was returned to 100% on July 7 and remained there for the remainder of the reporting period. The unit had operated continuously for 235 days prior to the tri Unit 2 -
Unit 2 commenced this reporting period operating at 100%
power with a calculated steam generator tube leak of approximately 0.02 gp On June 30, the air ejector radiation monitor (RIA-40)
increased to about 240,000 cpm indicating a leak rate increase to approximately 0.04 gp On July 6, RIA-40 count increased again to approximately 600,000 cpm indicating the leak had increased to about 0.12 gpm. The licensee decided to take the unit off the line on July 7 to correct the leaks in the 2A steam generator. The licensee identified one leaking tube (77-1)
at the 15th support plate in the 2A generato In addition they checked approximately 400 other tubes using eddy current testing and plugged one additional tube due to indications of wear. The licensee is in the process of returning this unit to normal operatio Unit 3 -
Unit 3 operated at 100% during this reporting perio *
3 Power Reduction Due to Reactor Coolant Pump (RCP)
Low Oil Level (Unit 1)
On June 29, 1988, at about 5 p.m. the 1B2 RCP was secured due to an indicated low oil level in the upper pot. Power was reduced to less than allowable maximum power limits with three RCPs operating prior to the pump being turned off. Power operation continued at 72% power (the Reactor Protection high power trip setpoint was reduced to 79%)
while a proposed resolution was develope The resident inspector attended the planning meeting at which solutions and safety issues were discusse On June 30 a slow power reduction was commenced and at about 8 on July 1, with the unit steady at 24% power a reactor building (RB)
entry was made to correct the proble Personnel in the RB verified the oil level by sight glass and did not observe any indications of a large oil lea Consequently approxi mately 20 gallons of oil was added to the RCP. Additionally repairs were made to the RB normal sump level instrumentation transmitter during the entr No unforeseen problems were encountered and the RCP was returned to operation at 9:30 Unit 1 power was subsequently increased.to 100% by about 5:00 p.m. on July c. Reactor Trip Due to Personnel Error During Troubleshooting On July 5, 1988, at 8:28 a.m., Oconee Unit 1 tripped from 100% powe The Reactor Protection System actuated the trip on a loss of both main feedwater pumps. The licensee's investigation determined that the trip was caused by an Instrument and Electrical (I&E) technician during troubleshooting of a problem in the turbine header pressure portion of the Smart Automatic Signal Selector (SASS)
System which provides several inputs to the Integrated Control System (ICS).
Apparently, the technician connected a digital multimeter set incorrectly on "amps" vice "volts" into the circuit causing a false high header pressure signal to be sent to the IC In response to this signal, the ICS began to reduce feedwater flow and reactor demand while opening the turbine control valve Then the false signal was removed and ICS increased feedwater flo The rapid increase in feedwater flow caused a low suction pressure trip of the condensate booster pumps which resulted in the loss of both main feedwater pumps and consequently a reactor tri Further investiga tion also revealed that valve C-61 (turbine generator cooler bypass valve) may have contributed to the decrease in condensate booster pump suction pressure by not operating properl The generator stator coolant is cooled by condensate flow through cooler C-61 is designed to open as differential pressure increases across the generator coolers to supply an increased bypass flow around those coolers to the condensate booster pumps. If the valve did not fully
open or was slow to open during the feedwater transient, it could have caused the condensate booster pump low suction pressure conditio computer records indicate that the valve did not trip open as expecte All other systems functioned as expected during and after the trip. Main steam relief valves were quickly reset and steam generator levels were maintained on emergency feedwater until the system stabilized and a main feedwater pump was restore The resident inspector observed the trip recovery actions, attended the licensee's post trip review meeting, and reviewed the post-trip review packag Although the inspectors observed no significant problems during the trip recovery and subsequent plant startup, several concerns arose out of this event;
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During the transient two chart recorders on the control board did not function properly (turbine header pressure and 1B feedwater flow).
The turbine header pressure chart apparently stuck at normal operating pressure and could have provided important information to the operators early in the transien These recorders are a new type being installed as a Human Engineering Development modificatio The licensee intends to look closely at the reliability of these new recorders (installed on Units 1 and 2) and compare them to the previously installed recorders (still being used on Unit 3).
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The possible contribution to the transient by valve C-61 indicates that further attention concerning the operation, maintenance and testing of this valve may be desirabl Additionally further emphasis may be necessary during operator training on this valve's operation (as well as several other key component bypass valves in the condensate system) and available corrective action in case of valve failur Prior to this trip, Oconee Unit 1 had operated continuously for 235 day The last reactor trip on Unit 1 occurred on May 10, 198 Lakewater Temperature As a result of the recent weather patterns and difficulties which arose last summer as a result of elevated Lake Keowee temperatures (see Inspection Reports 269,270,287/87-13,25,29,30), the licensee is closely monitoring and studying lakewater temperature trend Current licensee studies project a peak condenser circulating water (CCW)
inlet temperature of 85 degrees F about the first week of Septembe CCW inlet temperatures are already 3 to 4 degrees F higher this year than in 1987 and operation of all three units was expected until the Unit 3 scheduled refueling outage in early Augus The historical maximum temperature occurred in 1987 and was 82 degrees Last year safety related system and components were reanalyzed under the assumption that CCW inlet temperature would never exceed 85 degree *
Currently the licensee is examining the impact of exceeding 85 degrees CCW inlet temperature by reanalyzing all necessary plant equipment operation at up to 90 degrees CC Preliminary results indicate the performance of equipment under accident conditions will still meet requirements, but analysis is still in progres Initial indications are that the Safe Shutdown Facility (SSF)
HVAC system will not perform as required if CCW inlet temperature exceeds 85 degrees, but further analysis and examination of alternative solu tions is still in progres Due to successful cleaning of the Low Pressure Injection and Reactor Building Cooling Unit Coolers last year, the 1987 issue of adequate accident heat removal capability of these components will not be a concern even if lakewater temperature goes as high as 90 degree The licensee is also developing a detailed analysis model of Lake Keowee in order to predict CCW inlet temperatures and evaluate methods to minimize elevated lakewater temperature problems in the future by better utilization of the cold water available in Lake Keowe Environmental limits (condenser discharge and condenser differential temperature) are also being considere The resident inspectors will continue to closely follow the progress of the licensees actions on this situatio Reactor Protection System (RPS) and Engineered Safety Features (ESF)
Cabling Issue During the inspection period the resident inspectors closely followed the licensees actions in regards to concerns, about possible RPS and ESF wiring deficiencies. The inspectors observed the resolution of a number of the identified concerns listed in Inspection Report 269,270,287/88-13. Most of the inconsistencies were due to wiring being documented on different print series than those referred to during the inspection. Several discrepancies were found where wiring was not as designed. As a result of these findings the licensee initiated a thorough inspection of the as built configuration of the RPS, ESF and selected other electrical panel The resident will continue to closely follow this effor f. Emergency Power Switching Logic (EPSL)
The Emergency Power Switching Logic (EPSL)
System is designed to assure that a reliable source of power is available to the main feeder busses during a loss of power concurrent with a LOC The EPSL causes initiation of the load shed circuitry, transfer to the standby busses and retransfer to the startup electrical sources as required. The EPSL system is complex and its operation is difficult to fully understand. Additionally Technical Specification 3.7 which sets operability requirements on the EPSL is also not easily under stoo Recently several incidents have occurred which clearly illustrate that the knowledge level of onsite personnel concerning the functioning of the EPSL needs to be improved. Two examples are;
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LER 269/87-09 concerning EPSL inoperability due to incorrect removal of components for maintenanc Onsite personnel followed procedures that have been in place for years to remove a major electrical component from service, not realizing that this resulted in portions of the EPSL being inoperabl Operations personnel recently initiated a Problem Investigation Report in order to resolve an emergency power source operability question. While Design Engineering determined that no Technical Specification violation had occurred, it was noted that the system would have functioned differently than at least some of the operators thought it would hav (A loss of power to the standby bus would not have caused Unit 3 loads to close in on the startup source automatically as several operations personnel had believed.)
The inspectors are concerned that a lack of full understanding of how the EPSL system operates particularly among the Transmission and Operations Sections, may result in inadvertent Technical Specifica tion violations or rendering portions of the EPSL inoperabl While the EPSL system is very complex, its proper operation.is vital to safe plant operations and a detailed understanding of its functioning is necessary. The licensee has initiated an independent internal assessment of the EPSL system and intends to fully train all opera tions personnel upon its completio This item will be followed as Inspector Followup Item; 269,270,287/
88-15-01:
Retraining of Personnel on EPSL Operatio. Surveillance Testing (61726)
a. Surveillance tests were reviewed by the inspectors to verify procedural and performance adequac The completed tests reviewed were examined for necessary test prerequisites, instructions, acceptance criteria, technical content, authorization to begin work, data collection, independent verification where required; handling of deficiencies noted, and review of completed wor The tests witnessed, in whole or in part, were inspected to determine that approved procedures were available, test equipment was calibrated, prerequisites were met, tests were conducted according to procedure, test results were acceptable and systems restoration was complete *
Surveillances reviewed and/or witnessed in whole or in part:
IP/0/A/310/124 ES Digital Online Test (U-3)
IP/O/B/100/3 Security Microwave Checks IP/O/A/305/003 RPS Online Test (U-i)
IP/O/B/320/05 Resetting High Flux Limiter on Reactor Demand Subassembly (U-1)
of ICS IP/O/A/30i/003 Resetting High Flux Reactor Protection System Setpoints (U-1)
IP/0/A/310/13A HP-25 Functional Test (U-2) On June 29, 1988, the resident inspector was informed by station compliance that a schedule commitment made associated with inspection item 269,270,287/85-11-03: Correction of Design Deficiency in Nuclear Station Modification (NSM)
ON-1826 was closed after an inspector reviewed the issue in May 1987 (IR 269,270,287/87-18) and agreed with the proposed resolution since the corrective action was expected to be completed by June 15, 198 The licensee agreed to notify Region II in writing if this schedule could not be me Through an administrative error, station compliance tracked the commitment as due on July 1, 1988, and thus did not contact Region II. The actions are not yet completed due to material procurement problem This concerns replacement of a test switch so that testing of the Motor Driven Emergency Feedwater Pumps control oil pressure switches can b tested periodically without the use of temporary jumper After discussion with the inspector who closed out the item based on the earlier commitment, it was decided that the resident inspectors will followup on this ite The licensee now expects to have the modification completed by August 15, 198 No violations or deviations were identifie. Maintenance Activities (62703)
Maintenance activities were observed and/or reviewed during the reporting period to verify that work was performed by qualified personnel and that approved procedures in use adequately described work that was not within the skill of the trad Activities, procedures and work requests were examined to verify proper authorization to begin work, provisions for fire, cleanliness, and exposure control, proper return of equipment to service, and that limiting conditions for operation were me Maintenance reviewed and/or witnessed in whole or in part:
WR 15339C Repairs to Off Gas Monitor Flow Meter (Unit 2)
WR 92389C Work on SSF 267 Weld Leak WR 15951C Repair of 2FDW 372
8 Safeguards and Radiological Controls Activities (71709 and 71881)
In the course of the monthly activities, the Resident Inspectors included review of portions of the licensee's physical security activitie The performance of various shifts of the security force was observed in the conduct of daily activities which included; protected and vital areas access controls, searching of personnel, packages and vehicles, badge issuance and retrieval, escorting. of visitors, patrols and compensatory post The inspectors observed protected area lighting and protected and vital areas barrier integrity, and verified interfaces between the security organization and operations or maintenanc In addition, the inspectors observed portions of semi-annual testing of security microwave checks during this inspection perio Also included in the routine monthly activities were observations of radiological protection practices. These activities included reviews of radiological work permits, control of internal and external radiation exposures, posting of radiation requirements, observation of high radiation areas, and personnel entries into those area No violations or deviations were identifie. Inspection of Open Items (92701)
The following open items are being closed based on review of licensee reports, inspection, record review, and discussions with licensee personnel, as appropriate: URI 287/88-08-02 (Closed):
All Three LPI Pumps Administratively Inoperable at the Same Time. This item is closed since LER 287/88-01 which addresses this issue has been opened. (See below) (Closed)
Inspector Followup Item (270/86-33-01):
Repairs to Valve 2CF-1. Valve 2CF-1 was repaired in accordance with work request (WR)
54380 dated October 16, 1986 and WR 51629 dated February 10, 198 These WRs were reviewed by the inspector in addition to discussions with licensee management involving the work on the operato The valve has been returned to an operable status and the special guidance previously provided to the operations personnel has been cancelled. Based on this review this item is close (Open) LER 287/88-01: This LER addressed an incident in which all three Unit 3 Low Pressure Injection (LPI)
pumps were declared inoperable. The situation is discussed in Inspection Report 269,270, 287/88-08. The inspectors reviewed the LER, Incident Investigation Report, and applicable articles of Section XI of the ASME Cod The inspectors concur with the licensee's judgement that while it is good engineering practice to perform post lubrication testing, it is not
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required (by the code) after lubrication maintenance as described by this situation. The LPI pumps were in fact operable throughout this incident, no Technical Specification (or ASME Code requirement) was violate The inspectors also reviewed corrective actions both completed and planne The licensee will be changing station directives to more clearly set forth management's decision on when post maintenance testing is required after lubrication and how-it is to be performe Additionally the Performance Department will be changing their pump performance testing procedures as necessary to enable the maintenance lubrication to be scheduled in conjunction with the performance surveillance testing procedures. Since the root cause of this incident was determined to be a management deficiency in that administrative controls were not implemented to ensure post lubrication testing was performed in accordance with requirements as agreed upon by management, the inspectors will close out this item after a satisfactory review of revised directives is complete (Closed)
LER 269/87-12:
Technical Specification Violation Due to Exceeded Inservice Inspection Interval Resulting From A Quality Assurance Deficiency. This LER has been reviewed by the inspector and all corrective action specified has been complete Based on this review, this item is close (Closed) LER 287/88-02: Shutdown Due to OTSG Leak:
This report was a voluntary report to discuss the leaks discovered in Unit 3's A Once Through Steam Generator (OTSG). Two leaking tubes were identified in the A OTSG. As a result of this inspection 27 tubes were plugged in the A OTSG and 23 tubes plugged in the B OTSG. Based on a review of this information, this item is close. Safety System Functional Inspection Report Followup Items left open on the referenced inspection report (50-269,270,287/86-16)
were reviewed to'determine current status, as follows:
a. (Closed)
Unresolved Item (50-269,270,287/86-16-19):
Design Program Implementation of ANSI N45.2.11 Requirement During the SSFI inspection, the team identified weaknesses regarding the apparent failure to implement the requirements of ANSI N45.2.1 Region II Quality Assurance (QA)
personnel reviewed the licensees design modification program with respect to ANSI N45.2.1 The results of that inspection is detailed in Inspection Report 50-269,270,287/
88-13. Based on the inspection of the QA team, this item is close b. (Closed)
Unresolved Item (50-269,270,287/86-16-20):
Safety Related Classification of Instrumentatio This unresolved item identified various examples of apparently incorrect or missing safety related classifications of instrumentatio The licensee in correspondence
dated October 1, 1986 and December 16, 1986, stated a review of all instrumentation with respect to safety classification and update of appropriate drawings was currently being accomplished and that a consolidated Instrumentation and Control (I&C)
list was also being develope The inspector reviewed the weaknesses identified in paragraph 3.4.11 of IR 86-16 with the following comments:
(1) On the drawings identified in section (1),
revisions have been made to each drawing to correct the deficiencies note (2) On the drawings identified in section (2), a revision has been made to drawing 422FF-1 that identifies the core flood tank level instrument as a safety-related componen The other drawings that have been changed have a note on the drawing that states that the instruments are not qualified to safety-related standards but will be changed to safety-related components in accordance with Reg Guide 1.97 modification Each of the instruments addressed in this item have Nuclear Station Modifi cations (NSMs)
assigned and are presently scheduled for future outage accomplishmen (3) The drawings identified in section (3)
have been corrected and a review of selected various additional drawings found no instances of omitted stamped informatio The inspector also reviewed the I&C list which is now in use at the facilit Listed information includes identification that the subject instrument is safety-related. Based on this review this item is close (Closed) Unresolved Item (50-269,270,287/86-16-21):
Weaknesses Regarding Implementation and Documentation of Safety Evaluation As Required By 10 CFR 50.59. This subject was reviewed in detail during a Region II Quality Assurance inspection as detailed in Inspection Report 50-269,270,287/88-13. Based on the QA inspection identified above, this item is close (Closed)
Unresolved Item (50-269,270,287/86-16-22):
Drawing Deficiencies. All drawing discrepancies noted by the original inspection have been corrected with the following exceptions:
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Drawing OFD-122A-1.4 Revision 1 indicated an incorrect design flow rate. Discussions with licensee personnel indicate that although the term "design flow rate" is used on the drawings it is in fact not a "design flow rate" used for any controlled work. Since design work is not performed using this data, the licensee does not plan to revise drawings to correct this ite Drawing OM 245-068 2 has been supersede This drawing was replaced by OM 245-1297. The conflict previously shown on these drawings has been correcte The conflicts identified between the mechanical valve data list and the motor control center drawings have been correcte The licensee stated that the mechanical valve data list has never been used for design informatio (Closed) Open item (50-269,270,287/86-16-01): Resolution of Material Deficiencies. The inspection team identified material deficiencies as discussed in paragraph 3.1.5 of Inspection Report 86-16. These deficiencies have been corrected and similar components for the other units have also been checked for similar finding Based on this action this item is close (Closed)
Open item (50-269,270,287/86-16-03):
Correction of Valve Position Indication Wiring for valves MS-82 and MS-8 This deficiency identified that the valve position indication for these valves did not identify the position of the valve when the valve was in the intermediate position during travel. *Standard design for valves in this plant have both the open and shut indicator lights illuminated when a valve is in the intermediate positio The licensee has issued exempt changes on each unit to rewire the light circuits to be consistent with other similar valves at the plan In addition, two other valves (MS-96 and MS-97) were identified as having the same discrepancy and are being corrected with the same exempt change procedures. Based on this action this item is close.
Exit Interview The inspection scope and findings were summarized on July 14, 1988, with those persons indicated in paragraph 1 abov The inspectors described the areas inspected and discussed in detail the inspection findings listed below. Dissenting comments were not received from the license Proprietary information is not contained in this repor Item Number Status Description/Reference Paragraph 269,270,287/87-49-01 Closed Violation for failure to Maintain Containment Isolation During Refueling Operation 269,270,287/88-15-01 Open Inspector followup item associated with Retraining of Personnel on EPSL Operation
Item Number Status Description/Reference Paragraph (cont'd)
269,270,287/86-16-19 Closed Unresolved item discussing Design Program implementation of ANSI N45.2.11 Requirements 269,270,287/86-16-20 Closed Unresolved item discussing Safety-related classification of instrumentation 269,270,287/86-16-21 Closed Unresolved item discussing weaknesses regarding implementa tion and documentation of safety evaluations required by
CFR 50.59 269,270,287/86-16-22 Closed Unresolved item discussing drawing deficiencies 269,270,287/86-16-01 Closed Open item addressing material deficiencies during SSFI inspec tion 269,270,287/86-16-03 Closed Open item associated with open/
closed indication of MS-82 and MS-84