IR 05000424/2003007
| ML033570467 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 12/22/2003 |
| From: | Ogle C Division of Reactor Safety II |
| To: | Gasser J Southern Nuclear Operating Co |
| References | |
| IR-03-007 | |
| Download: ML033570467 (20) | |
Text
December 22, 2003
SUBJECT:
VOGTLE ELECTRIC GENERATING PLANT - NRC SAFETY SYSTEM DESIGN AND PERFORMANCE CAPABILITY INSPECTION REPORT NOS.
05000424/2003007 AND 05000425/2003007
Dear Mr. Gasser:
On November 21, 2003, the Nuclear Regulatory Commission (NRC) completed a safety system design and performance capability inspection at your Vogtle facility. The enclosed report documents the inspection findings which were discussed on November 21, 2003, with Mr. W. F. Kitchens and other members of your staff. Following completion of additional reviews in the Region II office, a final exit interview was held by telephone with Mr. M. Shebani, Vogtle Licensing Supervisor, on December 16, 2003.
This inspection was an examination of activities conducted under your license as they relate to safety and compliance with the Commissions rules and regulations, and with the conditions of your operating license. Within these areas, the inspection involved selected examination of procedures and representative records, observations of activities, and interviews with personnel.
No findings of significance were identified during this inspection.
In accordance with 10 CFR 2.790 of the NRC's "Rules of Practice," a copy of this letter and its enclosure will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of NRC's document system (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).
Sincerely,
/RA/
Charles R. Ogle, Chief Engineering Branch 1 Division of Reactor Safety Docket Nos.: 50-424, 50-425 License Nos.: NPF-68, NPF-81
Enclosure:
(See page 2)
SNOPCO
Enclosure:
NRC Inspection Report Nos. 05000424/2003007 and 05000425/2003007 w/Attachment: Supplemental Information
REGION II==
Docket Nos.:
50-424, 50-425 License Nos.:
05000424/2003007 and 05000425/2003007 Licensee:
Southern Nuclear Operating Company, Inc.
Facility:
Vogtle Electric Generating Plant Location:
7821 River Road Waynesboro, GA 30830 Dates:
November 3-7, 2003 November 17-21, 2003 Inspectors:
R. Moore, Senior Reactor Inspector (Lead Inspector)
R. Schin, Senior Reactor Inspector M. Maymi, Reactor Inspector S. Rudisail, Project Engineer R. Conney, Contractor Accompanied by:
N. Staples, Reactor Inspector Intern, Region II Approved by:
Charles R. Ogle, Chief Engineering Branch 1 Division of Reactor Safety
SUMMARY OF FINDINGS
IR 05000424/2003-007, 05000425/2003-007; 11/03-07/2003 and 11/17-21/2003; Vogtle Electric
Generating Plant, Units 1 and 2; Safety System Design and Performance Capability Inspection.
This inspection was conducted by a team of region based inspectors and one contract inspector. No findings of significance were identified. The NRCs program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, Reactor Oversight Process, Revision 3, dated July 2000.
NRC-Identified and Self-Revealing Findings
No findings of significance were identified.
B.
Licensee-Identified Findings None.
REPORT DETAILS
REACTOR SAFETY
Cornerstones: Initiating Events and Mitigating Systems
1R21 Safety System Design and Performance Capability
This team inspection reviewed selected components and operator actions that would be used to prevent or mitigate the consequences of a steam generator tube rupture (SGTR) event. Components in the main steam (MS), auxiliary feedwater (AFW), steam generator (SG) blowdown, chemical volume and control (CVCS), reactor coolant (RCS),and radiation monitoring systems were included. This inspection also covered supporting equipment, equipment which provides power to these components, and the associated instrumentation and controls. The SGTR event is a risk-significant event as determined by the licensees probabilistic risk assessment.
.1 System Needs
.11 Process Medium
a. Inspection Scope
The team reviewed the water sources for components and systems required for the mitigation of the SGTR event. These included the refueling water storage tank (RWST),volume control tank (VCT), and condensate storage tank (CST). The team reviewed the availability, reliability, and adequacy of the water sources with respect to the anticipated water source requirements for the SGTR event. The team reviewed pump performance curves, tank drawings, the Updated Final Safety Analysis Report (UFSAR), tank sizing calculations, and net positive suction head (NPSH) calculations for the AFW pumps and the centrifugal charging pumps (CCPs) to verify that design and accident analysis assumptions related to water volume and NPSH were consistent with system and equipment capability. These calculations were also reviewed to verify the adequacy of design assumptions and methodology. Additionally, the team reviewed completed maintenance work orders to verify preventive maintenance was performed on the CSTs bladders to ensure material condition had not deteriorated.
b. Findings
No findings of significance were identified.
.12 Energy Sources
a. Inspection Scope
The team reviewed the adequacy of energy sources for a sample of motors, valve operators, inverters, and radiation monitors used to mitigate a SGTR. This review included design basis documents, calculations, vendor information, and approved design output drawings for the Unit 1 Class 1E 4160 volt alternating current (VAC) and 480 VAC electrical distribution systems. The team also reviewed surveillance records on breaker alignment checks and bus voltage readings to verify that these checks were being performed in accordance with the requirements specified in the Technical Specifications (TS). The team reviewed the turbine driven AFW pump steam supply orifice inspections and bypass valve preventive maintenance instructions and frequency to verify the reliability of the steam supply and the adequacy of maintenance.
b. Findings
No findings of significance were identified.
.13 Instrumentation and Controls
a. Inspection Scope
The team reviewed the level instrumentation of the CST and the RWST, to verify that they were designed, constructed, and operated in accordance with design and licensing basis documents. The team also reviewed appropriate design basis documents, TS sections, UFSAR sections, system flow diagrams, instrument uncertainty calculations, calibration and surveillance test procedures, and calibration test records to verify that the instruments had the proper range and accuracy needed to perform their safety function. This included the radiation monitors in the digital radiation monitoring system.
Also reviewed was the licensees validation of the integrated plant computer program which processes radiation monitor input to determine a primary leak rate for a SGTR.
The team reviewed electrical control schematics of the SG atmospheric relief valves (ARVs), AFW motor driven and steam driven pumps, AFW pump mini-flow valves, and pressurizer power operated relief valves (PORVs) to verify that the control systems were in accordance with their design bases and would be functional and provide desired control during accident/event conditions. The team reviewed completed calibration and surveillance tests related to the motor-driven AFW pumps automatic motor-operated minimum flow valves to verify that the valves and their entire control circuits were being periodically tested.
The team reviewed surveillance and calibration records for process instrument channels monitoring SG level, SG pressure, RCS pressure, RCS temperature, pressurizer pressure, and pressurizer level to verify that the instruments and associated loop components were being properly calibrated and tested in accordance with calibration procedures and the TS. The calibration records were also reviewed to verify that instrument out of tolerance conditions were properly evaluated by the licensee for impact on system performance and, if applicable, entered into the corrective action program.
b. Findings
No findings of significance were identified.
.14 Operator Actions
a. Inspection Scope
The team reviewed emergency operating procedures (EOPs), abnormal operating procedures (AOPs), annunciator response procedures (ARPs), and operating procedures (OPs) that would be used in identification and mitigation of an SGTR event.
This procedure review was done to verify that the procedures were consistent with the UFSAR description of an SGTR event and with the owners group guideline procedures; any step deviations were justified and reasonable; and the procedures were written clearly and unambiguously. The team also reviewed relevant operator training lesson plans and job performance measures and discussed selected portions of them with operators to verify that they were consistent with the procedures. In addition, the team discussed the EOPs with procedure writers and operators and observed a simulator drill of an SGTR event to verify that the procedures and operator training were adequate to identify and mitigate an SGTR event.
b. Findings
No findings of significance were identified.
.15 Heat Removal
a. Inspection Scope
The team reviewed design calculations, drawings, test procedures, and surveillance documentation for selected equipment to assess the reliability and availability of cooling for equipment required to mitigate an SGTR event. These included the review of CCPs lube oil coolers, related maintenance work orders, preventive maintenance instructions and frequency, condition reports, engineering evaluations, flow surveillance tests and data trending to verify adequacy of maintenance and surveillance acceptance criteria.
The team also reviewed nuclear service cooling water (NSCW) fans inspection, preventive maintenance and monthly test procedures to verify adequacy of maintenance.
b. Findings
No findings of significance were identified.
.2 System Condition and Capability
.21 Installed Configuration
a. Inspection Scope
The team performed field inspections of selected components that could be used to mitigate an SGTR. This included equipment in the following systems: CVCS, AFW, main feedwater (FW), condensate, main steam (MS), 4160 VAC, 480 VAC, and 125 volt direct current (dc). The purpose of the inspections was to assess general material condition, verify that system alignments were consistent with design and licensing basis assumptions, and to identify degraded conditions of SGTR mitigation equipment.
The team reviewed system drawings and walked down the manual valves between the CST and the AFW pumps to verify that the valves were locked open as indicated on the system drawings. Further, the team inspected the motor driven AFW pumps automatic motor-operated minimum flow valves to verify that they were open when the pumps were not operating.
b. Findings
No findings of significance were identified.
.22 Operation
a. Inspection Scope
The team performed walk throughs of selected tasks to verify that human factors in the procedures and in the plant (e.g., clarity, lighting, noise, accessibility, labeling) were appropriate to support effective use of the procedures. The team walked through SGTR procedures, with radiological control technicians and chemistry personnel, that would be used to help operators identify the SG involved in the SGTR event, and walked through, with an operator, the EOP actions to manually operate an SG ARV and to switch the AFW pumps suction to the alternate CST. Additionally, the team reviewed procedural guidelines and performance records for the loose parts monitoring systems to verify that the systems were operational and were being used to monitor for loose parts in the reactor coolant system and steam generators.
b. Findings
No findings of significance were identified.
.23 Design
a. Inspection Scope
Mechanical Design The team reviewed mechanical design calculations, specifications, and the UFSAR accident analysis to identify the design criteria which defined the required capacity and capability of SGTR mitigation mechanical equipment. Surveillance test procedures and equipment monitoring activities were also reviewed to verify that the design criteria were appropriately translated into acceptance criteria. This included a review of an MS safety valve modification which removed the manual lift arm. The AFW pump performance curves were also reviewed to verify adequate brake horsepower was provided by the motor for pump runout conditions.
Electrical Design The team reviewed documentation of completed design changes, corrective maintenance, and preventive maintenance; and walked down selected components of the AFW, safety injection (SI), 4160 VAC, 125 VDC and 120 VAC systems to verify that these activities were maintaining the assumptions of the licensing and design bases.
During these reviews, the team focused on potential common mode failure vulnerabilities that could be introduced by design or maintenance activities. The team reviewed the uncertainty calculations for the RWST level, CST level and pressurizer pressure instrument loops to verify adequate incorporation of design setpoint values into the instrument calibration procedures. Design changes were reviewed to verify that system and equipment design functions were appropriately evaluated and maintained.
Design changes reviewed included the installation of a new noble gas detector (RE0810) on the steam jet air ejector and replacement of installed Barton AFW flow transmitters with Rosemount transmitters.
b. Findings
No findings of significance were identified.
.24 Testing and Inspection
a. Inspection Scope
The team reviewed documentation of completed surveillance tests, data trending, and inspections to verify that the tests and inspections were appropriately verifying that the assumptions of the licensing and design bases were being maintained. This review included surveillance testing of the CCPs and AFW pump discharge pressures and flowrates, AFW and MS valve stroke times, AFW stop check valve operation, and AFW pump vibration and oil testing. Additionally, electrical equipment testing in the 4160 VAC, 125 VDC and 120 VAC systems was reviewed. The team reviewed the surveillance testing and test records for the 125/250 VDC station batteries to verify that the battery capacity was adequate to supply and maintain in operable status, the required emergency loads for the design basis duty cycle.
b. Findings
No findings of significance were identified.
.3 Selected Components
.31 Component Degradation
a. Inspection Scope
The team reviewed inservice test program trending data, system health reports, maintenance and testing documentation, calibration records, work orders, preventive maintenance schedules, pump oil analysis reports, and condition reports to assess the licensees actions to verify and maintain the safety function, reliability and availability of selected components. The Maintenance Rule functional failures of selected components for the past five years were also reviewed. Additionally, the team reviewed potential common cause failure mechanisms due to flooding, maintenance, parts replacement and modifications. A list of equipment reviewed is included in the
.
b. Findings
No findings of significance were identified.
.32 Equipment/Environmental Qualification
a. Inspection Scope
The team conducted in-plant inspections to verify that the observable portion of selected mechanical components and electrical connections to those components were suitable for the environment expected under all conditions, including high energy line breaks.
The team reviewed electrical switchgear room heat up calculations for switchgear rooms which provide motive power to motor operated valves (MOVs) used during an SGTR event to verify the adequacy of the equipment environmental qualification for the period assumed in the station probabilistic risk assessment analysis (24hrs).
b. Findings
No findings of significance were identified.
.33 Equipment Protection
a. Inspection Scope
The team conducted in-plant inspections to verify that there was no observable damage to installations designed to protect selected components from potential effects of high winds, flooding, and high or low outdoor temperatures. The team used the internal plant flooding report to assess potential water depths and potential impact on instrumentation located in those areas.
b. Findings
No findings of significance were identified.
.34 Operating Experience
a. Inspection Scope
The team reviewed the licensees dispositions of operating experience reports related to the SGTR events at Palo Verde and Indian Point Nuclear Stations to verify that applicable insights from those reports had been applied to the station equipment and procedures. The team reviewed the licensees actions to address an industry issue related to monitoring the life of installed Rosemount transmitters. (NRC Bulletin 90-01, Supplement 1)
b. Findings
No findings of significance were identified.
.35 Steam Generator Inservice Inspection
a. Inspection Scope
The team performed a limited scope review of the inservice inspection program for the SGs to verify that SG tubes were being inspected as required by TS and procedures, tube conditions were assessed, and the progress of identified wear mechanisms was monitored.
b. Findings
No findings of significance were identified.
.36 Foreign Material Exclusion Control (FME) Program
a. Inspection Scope
The team reviewed the procedural guidelines for cleanliness requirements during maintenance with systems open to verify that controls existed to prevent the introduction of foreign material. These guidelines included a method for controlling and accounting for material, tools and parts. Additionally, the team reviewed Foreign Material Exclusion (FME) related CRs initiated in the past three years to determine if there was a history of FME issues.
b. Findings
No findings of significance were identified.
.4 Identification and Resolution of Problems
a. Inspection Scope
The team reviewed selected SGTR mitigation equipment problems identified in the licensees corrective action program to assess the adequacy of the corrective actions to prevent recurrence and the scope of broadness reviews to other plant equipment. This included CRs related to the MSIVs, CCPs lube oil coolers, AFW pump discharge MOVs and stop check valves.
In addition, the team reviewed work orders on risk significant equipment to evaluate failure trends. The team also reviewed the licensees performance in the identification of procedural deficiencies.
b. Findings
No findings of significance were identified.
OTHER ACTIVITIES
4OA6 Meetings, Including Exit
The lead inspector presented the inspection results to Mr. W. F. Kitchens, and other members of the licensee staff, at an exit meeting on November 21, 2003. Following completion of additional reviews in the Region II office, a final exit was held by telephone with Mr. M. Shebani, Vogtle Licensing Supervisor, on December 16, 2003. The licensee acknowledged the findings presented. Proprietary information is not included in this inspection report.
ATTACHMENT
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee
- B. Burmeister, Engineering Support Manager
- S. Douglas, Operations Manager
- B. Gover, System Engineer
- W. Kitchens, General Plant Manager
- J. Robinson, Operations Unit Supervisor
- R. Rowland, Operations Supervisor
NRC (attended exit meeting)
- T. Morrissey, Resident Inspector
LIST OF ITEMS
OPENED, CLOSED AND DISCUSSED
None
ATTACHMENT