IR 05000498/1997004
| ML20149H119 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 07/22/1997 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | |
| Shared Package | |
| ML20149H113 | List: |
| References | |
| 50-498-97-04, 50-498-97-4, 50-499-97-04, 50-499-97-4, NUDOCS 9707240215 | |
| Download: ML20149H119 (15) | |
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ENCLOSURE U.S. NUCLEAR REGULATORY COMMISSION
REGION IV
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J Docket Nos:
50-498, 50-499
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License Nos:
- Report No:
50-498/97-04, 50-499/97-04
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l Licensee:
Houston Lighting & Power Company Facility:
South Texas Project Electric Generating Station, Units 1 and 2 i
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Location:
8 Miles West of Wadsworth on FM 521
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.Wadsworth, Texas 77483 Dates:
May 18 through' June 28,1997 Inspectors:
D. P. Loveless, Senior Resident inspector J. M. Keeton, Resident inspector W. C. Sifre, Resident inspector l
R. A. Kopriva, Project Engineer, Branch A Approved by:
J. l. Tapia, Chief, Project Branch A j
Division of Reactor Projects
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l 9707240215 970722 PDR ADOCK 05000498 l
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EXECUTIVE SUMMARY South Texas Project, Units 1 and 2 NRC Inspection Report 50-498/97-04; 50-499/97-04 This resident inspection included aspects of licensee operations, engineering, maintenance, and plant support. The report covers a 6 week period of resident inspection.
Operations Control room operators maintained an excellent awareness of control board
indications and existing plant conditions (Section O1.1).
Power reductions were conducted as conservative measures prior to performing
repairs of the Main Feedwater Pump 13 and Main Transformer 2B (Section 01.1).
The material condition of systems and components was nots sorthy, and the
chemical and volume control system was properly aligned (Section O2.1).
Weaknesses observed during simulator training were identified by the training
instructors and properly addressed (Section 05.1).
Maintenance Maintenance activities observed were properly performed and appropriately
supported continued plant operations (Section M1.1).
On one occasion, technicians conservatively stopped work to verify that the proper
safety-related replacement part was being utilized (Section M1.1).
- The surveillance activities observed were performed in a well controlled manner and in accordance with the applicable Technical Specification surveillance requirements and approved procedures (Section M1.2).
Enaineerina Reactor thermal power was maintained within licensed limits as indicated by a well
maintained plant computer routine and as verified by sound manual calculation (Section E1.1).
The engineer's use of Xenon reactivity worth in shutdown margin calculations was
sound and conservatively implernented (Section E1.2).
- Failure to adequately complete an 18-month Technical Specification surveillance requirement for safety injection actuation and response time testing was a violation.
This licensee-identified and corrected violation is being treated as a noncited violation, consistent with Section Vll.B.1 of the NRC Enforcement Policy (Section E8.1).
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J-2-Plant Sucoort J
Reactor plant operators and radiation protection technicians were quick to respond to a backup of normal floor drains in the mechanical-auxiliary building and maintained good control over the inadvertent contamination (Section R1.2).
- Routine radiological controit and daily security force activities were properly i
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implemented (Sections R1.1 and S1.1).
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l Report Details
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Summarv of Plant Status At the beginning of this inspection period, Unit 1 was operating at 100 percent reactor power. On June 19, reactor power was reduced to 80 percent for increased safety margin during the repair of Steam Generator Feedwater Pump 13. The unit was returned to full power on June 22. On June 28, Unit 1 was removed from service for the purpose of testing the rod cluster control assemblies. At the end of this inspection period, the Unit 1 reactor was subcritical in Mode 2.
At the beginning of this inspection period, Unit 2 was operating at 13 percent reactor power. On May 18, the unit was removed from service to replace a flexible boot that had failed on Main Transformer 28. The unit was returned to power the same day and achieved 100 percent power on May 19. At the end of this inspection period, the Unit 2 reactor was operating at 100 percent steady-state power.
1. Op_erations
Conduct of Operations 01.1 Control Room Observations (Units 1 and 2)
a.
Inspection Scope (71707)
Using inspection Procedure 71707, the inspectors routinely observed the conduct of operations in the Units 1 and 2 control rooms. Frequent reviews of control board status, routine attendance at shift turnover meetings, observations of operator performance, and reviews of control room logs and documentation were performed.
The inspectors observed portions of the following evolutions in addition to full power operations:
Unit 2 outage to repair Main Transformer 28 (May 18)
Unit 1 down power for repair to Main Feedwater Pump 13 (June 19)
e Test operations of Standby Diesel Generator 21 (June 26)
e Unit 1 control rod testing outage (June 28)
b.
Observations and Findinas During routine observations and interviews, the inspectors determined that the control room operators were continually aware of existing plant conditions. During control rod testing conducted in Unit 1 on June 28, the inspectors observed the shift supervisor reminding the secondary plant operator to be vigilant in observing and evaluating control board indications. Operators responded to annunciator
alarms in accordance with approved procedures. Annunciator alarms were promptly
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announced to the control room staff who, in turn, acknowledged by restating the announcement. The unit supervisors remained cognizant of ongoing activities.
Communications techniques utilized during radio contacts routinely met l
management expectations. However, on several occasions, radio contacts failed to l
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.I delineate the minimum equipment description with information reported to the
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The inspectors routinely attended shift turnover meetings. The on-shift operators.
provided clear and concise'information to the oncoming operators. Oncoming
operators routinely reviewed the control room logs, discussed current plant
conditions,'and verified major equipment status. Plant managers and operations department managers were often observed attending and participating in shift i
turnover meetings.
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The inspectors also noted that the down power evolutions on May;18 and June 19 were conservative in that they were not specifically required for the associated equipment repair, c.
Conclusions The inspectors concluded 'that licensed operators in the control room performed 'in a professional manner and were continuously aware of existing plant conditions with a good focus on safety. ~ Shift turnover meetings were thorough and routinely i
attended by plant management. Power reductions were condu_ cted as conservative measures prior to performing repairs of the Main Feedwater Pump 13 and Main Transformer 2B
'O2 Operational Status of Facilities and Equipment
O 2.1 Plant Tours (Units 1 and 2)
a.
inspection Scope (71707)
The inspectors routinely toured the accessible portions of plant areas in Units 1 and 2. Areas of special attention during this inspection period included:
e Units 1 and 2 mechanical auxiliary buildings e
Units 1 and 2 electrical-auxiliary buildings e
Unit 1 auxiliary feedwater cubicles e
Standby Diesel Generator 21 room e
Units 1 and 2 fuel-handling buildings e
Unit 1 isolation valve cubicles b'.
Observations and Findinos in general, the inspectors observed that in both units, systems and components had been maintained in good material condition. In addition, foreign materials controls were observed to be in place during the inspection of Standb'y Diesel Generator 21.
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-3-On June 5, the inspectors performed a flow path verification of the chemical and volume control system components in the mechanical auxiliary building. The system flow path was verified to be in accordance with Plant Operating Procedure OPOP02-CV-0004, Revision 12, " Chemical and Volume Control System Subsystem," and Piping and instrumentation Diagram 5R179F05007. No alignment
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discrepancies were identified and the system components appeared to be in good condition.. However, two minor labeling errors were noted and reported to the unit supervisor, c.
Conclusions The inspectors concluded that the material condition of systems and components observed in both units was noteworthy. The chemical and volume control system was properly aligned.
Operator Training and Qualification 05.1 Simulator Trainina for Staff Crew (71707)
On June 11, the inspectors observed plant simulator requalification training for a staff crew. The simulated event was realistic and challenging. Several weaknesses were identified in the crew's performance. These weaknesses were identified as part of a training evolution and not part of an evaluated scenario. Training-instructors properly identified the weaknesses and discussed them w h the crew.
The inspectors determined that the training was of value to the staff crew.
II. Maintenance M1 Conduct of Maintenance M 1.1 General Comments on Field Maintenance Activities a.
Inspection Scooe (62707)
The inspectors observed portions of the following on-going work activities identified by their work authorization numbers:
Unit 1:
e 98179 Main Steam Isolation Bypass Valve 1B Pressure Switch Relocation e
111691 Inspect seismic switches for presence of seismic fasteners and j
install replacement fasteners and washers as appropriate l
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Unit 2:
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111692 Install seismic fasteners on FCI instruments in accordance with
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Engineering CREE 97-9597-1 b.
Observations and Findinas The inspectors found that the work performed was conducted in a' thorough and
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professional manner. The work was performed by knowledgeable, qualified technicians utilizing approved procedures. - Supervisors were observed providing an appropriate level of oversight. System engineers were observed providing quality technical support as needed. Prejob briefings were thorough and radiological controls were in place where applicable. The inspectors verified that equipment clearance orders were properly implemented.
During the work on Main Steam isolation Bypass Valve 1B, technicians noted that the model number of the new pressure switch was different from that'on the original switch. The technicians stopped work and verified that the switch had
'been procured from the correct class bin. System engineers verified that the
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manufacturer had changed the model number without changing the form, fit, or function of the switch. The inspectors concluded that the technicians' actions were appropriate and conservative.
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Conclusions The activities observed were conducted in a professional manner. Technicians demonstrated a good knowledge of systems and components. On one occasion, technicians conservatively stopped work to verify that the proper safety-related replacement part was being utilized.
M 1.2 General Comments on Surveillance Testina a
Insoection Scope (61726)
The inspectors observed portions of the following surveillance activities:
Unit 1:
o Plant Surveillance Procedure OPSP03-DG-0001, Revision 7, " Standby Diesel 11 Operability Test" e
. Plant Surveillance Procedure OPSP03-CS-0003, Revision 2, " Containment Spray Pump 1C(2C) Inservice Test."
e Plant Surveillance Procedure OPSP10-DM-0003, " Automatic Multiple Rod Drop Time Measurement."
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Obser/ations and Findinas The n,spectors found that the observed surveillance activities were performed in accordance with approved procedures. The inspectors verified that the test Good communications between the control equipment calibrations were current.
room operators and personnel performing the tests were noted. Prejob briefings were thorough and comprehensive.
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Conclusions The surveillance activities observed were performed in accordance with the applicable Technical Specification surveillance requirements and approved procedures.
Ill. Enaineerina E1 Conduct of Engineering E 1,1 Reactor Coolant Svstem Primary Plant Calorimetric a.
Insoection Scooe (37551)
The inspectors reviewed the licensee's program for the verification of the accuracy of the plant calorimetric power estimates including the Plant Computer Routine U1118. Licensed operators utilized this routine to ensure compliance with the licensed thermal power limit of 3800 Megawatts thermal. The following documents were reviewed:
Plant Engineering Procedure OPEP02-CU-0001, Revision 2, " Calorimetric o
Verification" Westinghouse Commercial Atomic Power WCAP-13441, " Westinghouse e
Revised Thermal Design Procedure Instrument Uncertainty Methodology."
Plant Surveillance Procedure OPSP03-NI-0001, Revision 8, " Power Range NI e
Channel Calibration."
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Observations and Findinas The inspectors verified that control room operators were properly utilizing Routine U1118 and thereby ensuring that the reactor was being operated at or below its licensed limit. Verification procedures were being implemented and properly provided confidence in the accuracy of the plant computer routine output.
The inspectors independently performed calculations in accordance with Procedure OPEP02-CU-0001 to ensure accuracy. Stated process instrument accuracies were also found to meet the criteria of the vendor's methodology.
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Conclusions
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Manual calculations properly verified the accuracy of the plant computer primary j
calorimetric routine. Operators were maintaining reactor thermal power at or below
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licensed limits within instrument accuracies.
E1.2 Minimum Reactor Coolant System Boron Concentration (37551)
The inspectors reviewed Revision 5 to Procedure OPSP10-DM-0003. This revision authorized the use of a conservative minimum Xenon worth in determining.
shutdown margin limits during control rod drop time testing. The purpose of this method of determining shut down margin was to reduce the amount of boric acid added to the reactor coolant system during mid-cycle testing. Therefore, licensed operators saved time and water in returning the unit to power.
The inspectors concluded that taking credit for the negative reactivity provided naturally by the postshutdown Xenon peak, was sound and provided sufficient conservatism to ensure that shutdown margin limits were met throughout the l
testing evolution. In addition, independent calculations were performed to verify the accuracy of the engineers calculations.
E8 Miscellaneous Engineering issues (92903)
E8.1 (Closed) LER 50-498/94-019: Failure to fully meet the requirements of Technical Specifications for time response testing of the reactor containment fan cooler, and t
the control room envelope heating, vcntilation and air conditioning systems, t
On November 9,1994, licensee engineers were reviewing the safety injection activation and response time test surveillance procedure as part of the surveillance
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procedure enhancement program and determined that the response time testing of
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the reactor containment fan cooler, control room envelope and fuel handling building heating, ventilation and air conditioning systems was not complete. This condition was caused by inadequacies in the 18-month surveillance test procedure. A
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determination was made that the spin-up times of the fans had not been considered I
int he time response acceptance criteria.
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l The licensee entered Technical Specification 4.0.3 for both units, in order to
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complete the surveillance requirements. The spin-up times were obtained for the.
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affected fans of both Units using motor current decay measurements. Those times l
were applied to times to breaker closure and verified to be less than the Technical i
Specification required values. Both units exited Technical Specification 4.0.3 on
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November 10,1994.
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The licensee's corrective action included:
Spin-up times had been obtained for the affected fans of both Units using
motor current decay measurements. Those times were added to times to breaker closure and verified to be less than the Technical Specification required values for overall requirements.
- The safety injection actuation and response time test surveillance procedure was revised to include spin-up time for reactor containment fan cooler and the control room enveloped heating, ventilation and air conditioning systems.
- The licensee recognized deficiencies in the surveillance procedures and dealt with them under the Surveillance Procedure Enhancement Program.
The inspector determined that these corrective actions fully met the requirements of the Technical Specifications. In addition, the NRC staff had been monitoring the licensee's progress with respect to surveillance procedure upgrades and have noted continual improvements with the station procedures. However, the failure to fully l
meet the Technical Specification surveillance requirements because of an-l inadequate surveillance procedure is a violation. This licensee-identified and corrected viohtion is being treated as a noncited violation, consistent with Section Vll.B.1 of the NRC Enforcement Policy (498;499/97004-01).
E8.2 (Closed) LER 50-499/95-001: Pctential Slight Degradation of Decay Heat Removal Capacity Via Natural Circulation.
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On January 19,1995, licensee engineers had reviewed an industry experience notification concerning a degraded standby decay heat removal capability event.
They determined that there had been three instances when only one residual heat removal train was operable with the reactor coolant system vented to atmosphere and credit being taken for steam generators as backup decay heat removal sources.
Although the licensee had met the Technical Specifications conditions, the ability to remove decay heat via the stream generators may have been slightly degraded during the period that the reactor coolant system'was open to the atmosphere.
The cause of the event was a failure to fully evaluate the thermodynamic basis of the Technical Specifications. The specifications basis assumption was that the steam generators would be capable of removing decay heat by natural circulation whenever the reactor coolant system loops were full. This capability was challenged with the reactor coolant system vented to the atmosphere. An engineering evaluation completed on February 21,1995, concluded that the steam generators would have been capable of removing decay heat for at least 75 hours8.680556e-4 days <br />0.0208 hours <br />1.240079e-4 weeks <br />2.85375e-5 months <br /> before boiling would have occurred. That would have been sufficient time for
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action to be taken to mitigate any adverse event.
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The licensee's corrective action included:
e Voluntary submission of Inis LER to inform the NRC of the problem
e Licensed operators were briefed concerning this issue and the thermodynamic basis to ensure that a similar event does not occur.
e Appropriate procedures were revised to ensure guidance provided to rely upon natural circulation would be adequate for plant conditions.
The inspector determined that these corrective actions were sufficient to resolve the potential concern of a degraded decay heat removal capacity via natural circulation.
No violation was identified.
IV. Plant Support R1 Radiological Protection and Chemistry Controls R1.1 Tours of Radioloaical Controlled Areas a.
Insoection Scope (71750)
The inspectors routinely toured the mechanical-auxiliary and fuel-handling buildings in Units 1 and 2. These tours included observation of work, verification of proper radiological work permits, sampling of locked doors, and observations of personnel entrance to and egress from the radiological controlled areas.
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Observations and Controls Radiological housekeeping in the areas toured was very good. Doors required to be locked in accordance with Technical Specification 6.12.2 and the licensee's radiological program were properly secured. No entrance / egress discrepancies were identified. Postings and labeling of radiological areas were perforrned in accordance with the licensee's procedures. These procedures met the requirements identified in 10 CFR Part 20.
In addition, the inspectors reviewed the control room monitors for the plant stack, vents, and effluent releases, and determined that allindications were within the required specifications indicating no uncontrolled releases.
During the Unit 1 shutdown on June 28, the inspectors noted an iodine activity level spike in the reactor coolant system. The system engineer stated that the spike had been anticipated based on the presence of small fuelleaks in the core and past operational history. The inspectors reviewed the acceptance criteria for iodine levels and verified that the magnitude of the spike had not exceeded any of the specifications.
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Conclusions
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Routine radiological controls observed were considered in place and effective.
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R1.2 Scread of Contamination in the Unit 1 Mechanical-Auxiliary Buildina (71750)
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Event Descriotion On May 21, a reactor plant operator identified water backing up through the normal i --
floor drains located on the 41-foot elevation level of the mechanical-auxiliary j'
building (MAB). Operations personnel were in the process of pumping down the sump area between the fuel handling building and the reactor containment building.
Valve 1-WL-0311 was found to be not fully opened, and the sump pump capacity
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exceeded the capacity of the partially opened valve. As a result, the excess water l
backed up through the MAB floor drains. The water being pumped from'the sump area was clean, ground seepage water, but the drain piping had been slightly contaminated causing the water backing up through the drains and onto the floor of i
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the MAB to also be slightly contaminated.
The condition was identified shortly after pumping had commenced. Engineers estimated that approximately 100-300 gallons of water had backed up into the
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drains and onto the floor area. Operators and the radiation protection technicians
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immediately took control of the area, limiting access and commenced an inspection j
of the affected floor area including other areas and floors that may have been L
affected. Operators quickly identified the problem of the partially opened valve and ~
l corrected the error. Radiation protection personnel were then able to clean and l
decontaminate the affected areas. Condition Report CR 97-9009 was written to document and evaluate the event.
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Observations and Findinas Upon hearing the announcement by control room operators of limiting access to the identified areas of the MAB, the inspectors reported to the control room. The
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operators thoroughly explained the event and current clean up activities. The l
inspectors reviewed the condition report and subsequent investigation reports l
pertaining to the event. The inspector also interviewed several operators and radiation protection personnel in conjunction with the event and found the actions
taken to be responsive and appropriate for the event. The licensee's investigation into the problem of the partially opened valve identified that one of the multiple knuckles on a valve reach rod had broken providing the operator a response similar
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to that of a fully opened valve.
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Conclusions I
i The inspectors concluded that the reactor plant operators and radiation protection technicians were quick to respond to the event and took the necessary and
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became involved with the event and provided appropriate oversight in investigating the event and decontaminating the affected areas.
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P2 Status of EP Facilities, Equipment, and Resources (71750)'
I During this inspection period, the inspectors toured the emergency offsite facility.
The facility was in good condition, in standby readiness, and free of materials not related to emergency response.
S1 Conduct of Security and Safeguards Activities S 1.1 Daily Physical Security Activity Observations (71750)
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Inspection Scoce (71750)
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The inspectors observed the practices of security force personnel and the condition of security equipment on a daily basis.
b.
Obsuvations and Findinos i
l The integrity of the protected area was inspected and no problems or concerns
were identified. The barrier had no openings, nor was there any degradation or
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damage noted. Illumination levels within the protected area, including temporary
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lighting, was sufficient.
Personnel' access at the protected area access control points was implemented well by the security force. Packages and material access controls at the protected area access point were screened or searched by trained and authorized individuals. The l
individuals performing these activities were knowledgeable and professional in performing their duties. No concerns were identified.
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Conclusions l
. The inspectors concluded that the integrity of the protected area barriers was very l
well maintained. Illumination levels within the protected area were satisfactory and l
met or exceeded the requirements. Personnel access, packages and material access control was performed well oy the security force. The inspector noted that security officers were k.'owledgeable of their assigned duties and professional in performing their duties, l
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ATTACHMENT
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SUPPLEMENTAL INFORMATION
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PARTIAL LIST OF PERSONS CONTACTED
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Licensee.
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T. Cloninger, Vice President, Nuclear Engineering
W. Cottle, Executive' Vice President and General Manager Nuclear
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B. Dowdy, Manager, Operations, Unit 2 J. Groth, Vice President Nuclear Generation E. Halpin, Manager, Maintenance, Unit 2
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S. Head, Licensing Supervisor
K. House, Supervising Engineer, Design Engineering Department M. Kanavos,- Manager, Mechanical / Civil Design Engineering D. LeGrand, Performance Assessment Supervisor, Operations Support -
B. Logan, Manager, Health Physics R. Lovell, Manager, Operations, Unit 1
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B. Masse, Plant Manager, Unit 2
G. Parkey, Plant Manager, Unit 1-l M. Sicard, Acting Assistant to the Manager, Operations, Unit 2 j
F. Timmons, Manager, Nuclear Plant Protection
T. Waddell, Manager, Maintenance, Unit 1 j
INSPECTION PROCEDURES USED IP 37551: Onsite Engineering IP 61726; Surveillance Observations IP 62707: Maintenance Observation IP.71707: Plant Operations IP 71750: Plant Support IP.92903: Followup' - Engineering ITEMS OPENED, CLOSED, AND DISCUSSED
. Opened 498/97004-01 NCV Failure to fully meet the requirements of Technical Specifications for time response testing of the Reactor Containment Fan Cooler, and the Control Room Envelope Heating, Ventilation and Air Conditioning Systems.
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-2-Closed 498/97004-01 NCV Failure to fully meet the requirements of Technical Specifications for time response testing of the Reactor
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Containment Fan Cooler, and the Control Room I
l Envelope Heating, Ventilation and Air Conditioning Systems.
50-498/94-019 LER Failure to fully meet the requirements of Technical
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Specifications for time response testing of the Reactor Containment Fan Cooler, and the Control Room
Envelope Heating, Ventilation and Air Conditioning Systems.
50-499/95-001 LER Potential Slight Degradation of Decay Heat Removal Capacity Via Natural Circulation.
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