IR 05000498/2017001
| ML17130A952 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 05/10/2017 |
| From: | John Dixon NRC/RGN-IV/DRP/RPB-B |
| To: | Gerry Powell South Texas |
| JOHN DIXON | |
| References | |
| IR 2017001 | |
| Download: ML17130A952 (43) | |
Text
May 10, 2017
SUBJECT:
SOUTH TEXAS PROJECT ELECTRIC GENERATING STATION - NRC INTEGRATED INSPECTION REPORT 05000498/2017001 AND 05000499/2017001
Dear Mr. Powell:
On March 31, 2017, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your South Texas Project Electric Generating Station, Units 1 and 2, facility. On April 6, 2017, the NRC inspectors discussed the results of this inspection with Mr. D. Koehl, President and Chief Executive Officer, and other members of your staff. The results of this inspection are documented in the enclosed report.
The NRC inspectors did not identify any finding or violation of more than minor significance.
This letter, its enclosure, and your response (if any) will be made available for public inspection and copying at http://www.nrc.gov/reading-rm/adams.html and at the NRC Public Document Room in accordance with 10 CFR 2.390, Public Inspections, Exemptions, Requests for Withholding.
Sincerely,
/RA/
John L. Dixon, Branch Chief Project Branch B Division of Reactor Projects Docket Nos.: 50-498 and 50-499 License Nos.: NPF-76 and NPF-80
Enclosure:
Inspection Report 05000498/2017001 and 05000499/2017001 w/ Attachments:
1. Supplemental Information 2. Information Request for Public Radiation Safety Inspection 3. Information Request for O
REGION IV==
Docket: 05000498, 05000499 License: NPF-76, NPF-80 Report: 05000498/2017001 and 05000499/2017001 Licensee: STP Nuclear Operating Company Facility: South Texas Project Electric Generating Station, Units 1 and 2 Location: FM 521 - 8 miles west of Wadsworth Wadsworth, Texas 77483 Dates: January 1 through March 31, 2017 Inspectors: A. Sanchez, Senior Resident Inspector N. Hernandez, Resident Inspector L. Carson, II, Senior Health Physicist J. Drake, Senior Reactor Inspector S. Janicki, Project Engineer S. Money, Health Physicist J. ODonnell, CHP, Health Physicist M. Phalen, Senior Health Physicist Approved By: John L. Dixon, Chief, Project Branch B Division of Reactor Projects Enclosure
SUMMARY
IR 05000498/2017001, 05000499/2017001; 01/01/2017 - 03/31/2017; South Texas Project
Electric Generating Station, Units 1 and 2; Integrated Inspection Report The inspection activities described in this report were performed between January 1 and March 31, 2017, by the resident inspectors at the South Texas Project and inspectors from the NRCs Region IV office. The significance of inspection findings is indicated by their color (i.e., Green, greater than Green, White, Yellow, or Red), determined using Inspection Manual Chapter 0609, Significance Determination Process, dated April 29, 2015. Their cross-cutting aspects are determined using Inspection Manual Chapter 0310, Aspects within the Cross-Cutting Areas, dated December 4, 2014. Violations of NRC requirements are dispositioned in accordance with the NRC Enforcement Policy. The NRCs program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, Reactor Oversight Process, dated July 2016.
No findings were identified.
PLANT STATUS
Unit 1 began the inspection period at 100 percent power. On March 17, 2017, Unit 1 performed a rapid shutdown due to an open loop cooling pipe break that challenged secondary side cooling and flooded portions of the protected area. This unplanned shutdown occurred one day before the planned 1RE20 Refueling Outage. Unit 1 entered Refueling Outage 1RE20 and remained there through the end of the inspection period.
Unit 2 began the inspection period at 100 percent power and remained there for the rest of the inspection period.
REPORT DETAILS
REACTOR SAFETY
Cornerstones: Initiating Events, Mitigating Systems, and Barrier Integrity
1R01 Adverse Weather Protection
Readiness for Impending Adverse Weather Conditions
a. Inspection Scope
On February 14, 2017, the inspectors completed an inspection of the stations readiness for impending adverse weather conditions. The inspectors reviewed plant design features, the licensees procedures to respond to tornadoes and high winds, and the licensees implementation of these procedures. The inspectors evaluated operator staffing and accessibility of controls and indications for those systems required to control the plant.
These activities constituted one sample of readiness for impending adverse weather conditions, as defined in Inspection Procedure 71111.01.
b. Findings
No findings were identified.
1R04 Equipment Alignment
.1 Partial Walk-Down
a. Inspection Scope
The inspectors performed partial system walk-downs of the following risk-significant systems:
- February 8, 2017, Unit 1, train A essential cooling water
- March 29, 2017, Unit 1, spent fuel pool cooling system The inspectors reviewed the licensees procedures and system design information to determine the correct lineup for the systems. They visually verified that critical portions of the systems and trains were correctly aligned for the existing plant configuration.
These activities constituted two partial system walk-down samples as defined in Inspection Procedure 71111.04.
b. Findings
No findings were identified.
.2 Complete Walk-Down
a. Inspection Scope
On February 23, 2017, the inspectors performed a complete system walk-down inspection of the Units 1 and 2 Class 1E DC distribution system. The inspectors reviewed the licensees procedures and system design information to determine the correct Class 1E DC distribution system lineup for the existing plant configuration. The inspectors also reviewed outstanding work orders, open condition reports, in-process design changes, temporary modifications, and other open items tracked by the licensees operations and engineering departments. The inspectors then visually verified that the system was correctly aligned for the existing plant configuration.
These activities constituted one complete system walk-down sample, as defined in Inspection Procedure 71111.04.
b. Findings
No findings were identified.
1R05 Fire Protection
Quarterly Inspection
a. Inspection Scope
The inspectors evaluated the licensees fire protection program for operational status and material condition. The inspectors focused their inspection on four plant areas important to safety:
- January 9, 2017, Unit 1, train A diesel generator building diesel air intake/exhaust, Fire Area 38, Fire Zone Z514
- February 2, 2017, Unit 1, electrical auxiliary building auxiliary shutdown area, Fire Area 07, Fire Zone Z071
- February 8, 2017, Unit 1, fuel handling building heating, ventilation, and air conditioning equipment, Fire Area 35, Fire Zone Z303
- March 14, 2017, Unit 2, train A electrical auxiliary building engineered safety features switchgear room, Fire Zone Z042 For each area, the inspectors evaluated the fire plan against defined hazards and defense-in-depth features in the licensees fire protection program. The inspectors evaluated control of transient combustibles and ignition sources, fire detection and suppression systems, manual firefighting equipment and capability, passive fire protection features, and compensatory measures for degraded conditions.
These activities constituted four quarterly inspection samples, as defined in Inspection Procedure 71111.05.
b. Findings
No findings were identified.
1R11 Licensed Operator Requalification Program and Licensed Operator Performance
.1 Review of Licensed Operator Requalification
a. Inspection Scope
On February 28, 2017, the inspectors observed simulator training for an operating crew.
The inspectors assessed the performance of the operators and the evaluators critique of their performance. The inspectors also assessed the modeling and performance of the simulator during the requalification activities.
These activities constituted completion of one quarterly licensed operator requalification program sample, as defined in Inspection Procedure 71111.11.
b. Findings
No findings were identified.
.2 Review of Licensed Operator Performance
a. Inspection Scope
On March 17, 2017, the inspectors observed the performance of on-shift licensed operators in the plants main control room. At the time of the observations, Unit 1 was being rapidly shut down due to a significant leak in the open loop cooling system, In addition, the inspectors assessed the operators adherence to plant procedures, including conduct of operations procedure and other operations department policies.
These activities constituted completion of one quarterly licensed operator performance sample, as defined in Inspection Procedure 71111.11.
b. Findings
No findings were identified.
1R12 Maintenance Effectiveness
Routine Maintenance Effectiveness
a. Inspection Scope
The inspectors reviewed two instances of degraded performance or condition of safety-significant structures, systems, and components (SSCs):
- January 4, 2017, Unit 2, solid state protection system, during a calibration of the over temperature/ delta temperature loop T-420 channel associated with the axial flux difference, the bistable failed to actuate and send a trip signal to solid state protection system as designed
- January 15, 2017, Unit 2, 7300 process control system, while at 100 percent power, the master pressurizer controller failed due to 7300 controller driver board and resulted in operator action to ensure licensed power limits were not exceeded The inspectors reviewed the extent of condition of possible common cause SSC failures and evaluated the adequacy of the licensees corrective actions. The inspectors reviewed the licensees work practices to evaluate whether these may have played a role in the degradation of the SSCs. The inspectors assessed the licensees characterization of the degradation in accordance with 10 CFR 50.65 (the Maintenance Rule), and verified that the licensee was appropriately tracking degraded performance and conditions in accordance with the Maintenance Rule.
These activities constituted completion of two maintenance effectiveness samples, as defined in Inspection Procedure 71111.12.
b. Findings
No findings were identified.
1R13 Maintenance Risk Assessments and Emergent Work Control
a. Inspection Scope
The inspectors reviewed four risk assessments performed by the licensee prior to changes in plant configuration and the risk management actions taken by the licensee in response to elevated risk:
- January 11, 2017, Unit 1, train B 10kVA inverter EIV-1203 entry into the Configuration Risk Management Program for planned maintenance
- January 12, 2017, Unit 1, train B 125 Vdc battery bank E1B11 discharge test and entry into the Configuration Risk Management Program for planned maintenance
- February 3, 2017, Unit 1, train B replacement of train S, loop 2 channel 1 input relay and universal logic card for planned maintenance
- February 27, 2017, Unit 1, train B planned maintenance on electrical auxiliary building heating, ventilation, and air conditioning system The inspectors verified that these risk assessments were performed timely and in accordance with the requirements of 10 CFR 50.65 (the Maintenance Rule) and plant procedures. The inspectors reviewed the accuracy and completeness of the licensees risk assessments and verified that the licensee implemented appropriate risk management actions based on the result of the assessments.
The inspectors also reviewed the licensees action for implementing the Configuration Risk Management Program for determining and implementing the risk-informed allowed outage time for inverter EIV-1203 and battery bank E1B11 planned maintenance that took place on the dates above.
The inspectors also observed portions of two emergent work activities that had the potential to cause an initiating event, and to affect the functional capability of mitigating systems:
- February 11, 2017, Unit 2, train B essential cooling water pump started, but failed to run due to the failure of the discharge valve MOV-0137 to open
- February 20, 2017, Unit 1, circulating water pump 12 failure due to a sheered shaft while circulating water pump 14 was being overhauled The inspectors verified that the licensee appropriately developed and followed a work plan for these activities. The inspectors verified that the licensee took precautions to minimize the impact of the work activities on unaffected SSCs.
These activities constituted completion of six maintenance risk assessments and emergent work control inspection samples, as defined in Inspection Procedure 71111.13.
b. Findings
No findings were identified.
1R15 Operability Determinations and Functionality Assessments
a. Inspection Scope
The inspectors reviewed four operability determinations and functionality assessments that the licensee performed for degraded or nonconforming SSCs:
- January 13, 2017, operability determination of feedwater temperature sensors drifting and losing calibration
- February 27, 2017, functionality assessment of feedwater heaters 21A and 22B not receiving post weld heat treatments following installation
- March 16, 2017, operability determination for Unit 1 personnel airlock door
- March 29, 2017, operability determination for scratched fuel discovered during new fuel receipt for Unit 1 operating cycle 21 The inspectors reviewed the timeliness and technical adequacy of the licensees evaluations. Where the licensee determined the degraded SSC to be operable, the inspectors verified that the licensees compensatory measures were appropriate to provide reasonable assurance of operability. The inspectors verified that the licensee had considered the effect of other degraded conditions on the operability of the degraded SSC.
These activities constituted completion of four operability and functionality review samples, as defined in Inspection Procedure 71111.15.
b. Findings
No findings were identified.
1R19 Post-Maintenance Testing
a. Inspection Scope
The inspectors reviewed four post-maintenance testing activities that affected risk-significant SSCs:
- January 10, 2017, Unit 1, train A emergency diesel generator following replacement of cracked varistors
- February 9, 2017, Unit 2, train A steam generator 2A feedwater regulating valve universal control circuit card following replacement due to erroneous signal
- February 14, 2017, Unit 2, train B essential cooling water pump following breaker auxiliary contact replacement for the discharge motor-operated valve
- February 15, 2017, Unit 2, train B electrical auxiliary building heating, ventilation, and air conditioning following replacement of charcoal adsorber The inspectors reviewed licensing- and design-basis documents for the SSCs and the maintenance and post-maintenance test procedures. The inspectors observed the performance of the post-maintenance tests to verify that the licensee performed the tests in accordance with approved procedures, satisfied the established acceptance criteria, and restored the operability of the affected SSCs.
These activities constituted completion of four post-maintenance testing inspection samples, as defined in Inspection Procedure 71111.19.
b. Findings
No findings were identified.
1R20 Refueling and Other Outage Activities
a. Inspection Scope
During the Unit 1 Refueling Outage 1RE20, that commenced on March 17, 2017, the inspectors evaluated the licensees outage activities. The inspectors verified that the licensee considered risk in developing and implementing the outage plan, appropriately managed personnel fatigue, and developed mitigation strategies for losses of key safety functions. This verification included the following:
- Review of the licensees outage plan prior to the outage
- Monitoring of shut-down and cool-down activities
- Verification that the licensee maintained defense-in-depth during outage activities
- Observation and review of reduced-inventory activity
- Observation and review of fuel handling activities These activities constituted completion of one refueling outage sample, as defined in Inspection Procedure 71111.20.
b. Findings
No findings were identified.
1R22 Surveillance Testing
a. Inspection Scope
The inspectors observed five risk-significant surveillance tests and reviewed test results to verify that these tests adequately demonstrated that the SSCs were capable of performing their safety functions:
In-service tests:
- March 15, 2017, Unit 1, train C essential cooling water pump
- March 23, 2017, Unit 2, train C high head safety injection pump
- March 30, 2017, Unit 2, train D auxiliary feedwater pump
- March 31, 2017, Unit 1, train B high head safety injection pump comprehensive test Other surveillance tests:
- January 11, 2017, Unit 2, train A nuclear instrument 44 axial flux difference calibration The inspectors verified that these tests met technical specification requirements, that the licensee performed the tests in accordance with their procedures, and that the results of the test satisfied appropriate acceptance criteria. The inspectors verified that the licensee restored the operability of the affected SSCs following testing.
These activities constituted completion of five surveillance testing inspection samples, as defined in Inspection Procedure 71111.22.
b. Findings
No findings were identified.
RADIATION SAFETY
Cornerstones: Public Radiation Safety and Occupational Radiation Safety
2RS1 Radiological Hazard Assessment and Exposure Controls
a. Inspection Scope
The inspectors evaluated the licensees performance in assessing the radiological hazards in the workplace associated with licensed activities. The inspectors assessed the licensees implementation of appropriate radiation monitoring and exposure control measures for both individual and collective exposures. During the inspection, the inspectors interviewed licensee personnel, walked down various areas in the plant, performed independent radiation dose rate measurements, and observed postings and physical controls. The inspectors reviewed licensee performance in the following areas:
- Radiological hazard assessment, including a review of the plants radiological source terms and associated radiological hazards. The inspectors also reviewed the licensees radiological survey program to determine whether radiological hazards were properly identified for routine and non-routine activities and assessed for changes in plant operations.
- Instructions to workers including radiation work permit requirements and restrictions, actions for electronic dosimeter alarms, changing radiological condition, and radioactive material container labeling.
- Contamination and radioactive material control, including release of potentially contaminated material from the radiologically controlled area, radiological survey performance, radiation instrument sensitivities, material control and release criteria, and control and accountability of sealed radioactive sources.
- Radiological hazards control and work coverage. During walk-downs of the facility and job performance observations, the inspectors evaluated ambient radiological conditions, radiological postings, adequacy of radiological controls, radiation protection job coverage, and contamination controls. The inspectors also evaluated dosimetry selection and placement as well as the use of dosimetry in areas with significant dose rate gradients. The inspectors examined the licensees controls for items stored in the spent fuel pool and evaluated airborne radioactivity controls and monitoring.
- High radiation area and very high radiation area controls. During plant walk-downs, the inspectors verified the adequacy of posting and physical controls, including areas of the plant with the potential to become risk-significant high radiation areas.
- Radiation worker performance and radiation protection technician proficiency with respect to radiation protection work requirements. The inspectors determined if workers were aware of significant radiological conditions in their workplace, radiation work permit controls/limits in place, and electronic dosimeter dose and dose rate set points. The inspectors observed radiation protection technician job performance, including the performance of radiation surveys.
- Problem identification and resolution for radiological hazard assessment and exposure controls. The inspectors reviewed audits, self-assessments, and corrective action program documents to verify problems were being identified and properly addressed for resolution.
These activities constitute completion of the seven required samples of radiological hazard assessment and exposure control program, as defined in Inspection Procedure 71124.01.
b. Findings
No findings were identified.
2RS3 In-Plant Airborne Radioactivity Control and Mitigation
a. Inspection Scope
The inspectors evaluated whether the licensee controlled in-plant airborne radioactivity concentrations consistent with as ALARA principles and that the use of respiratory protection devices did not pose an undue risk to the wearer. During the inspection, the inspectors interviewed licensee personnel, walked down various areas in the plant, and reviewed licensee performance in the following areas:
- Engineering controls, including the use of permanent and temporary ventilation systems to control airborne radioactivity. The inspectors evaluated installed ventilation systems, including review of procedural guidance, verification the systems were used during high-risk activities, and verification of airflow capacity, flow path, and filter/charcoal unit efficiencies. The inspectors also reviewed the use of temporary ventilation systems used to support work in contaminated areas such as high-efficiency particulate air/charcoal negative pressure units.
Additionally, the inspectors evaluated the licensees airborne monitoring protocols, including verification that alarms and set points were appropriate.
- Use of respiratory protection devices, including an evaluation of the licensees respiratory protection program for use, storage, maintenance, and quality assurance of National Institute for Occupational Safety and Health certified equipment, air quality and quantity for supplied air devices, and self-contained breathing apparatus (SCBA) bottles, qualification and training of personnel, and user performance.
- SCBA for emergency use, including the licensees capability for refilling and transporting SCBA bottles to and from the control room and operations support center during emergency conditions, hydrostatic testing of SCBA bottles, status of SCBA staged and ready for use in the plant, including vision correction, mask sizes, etc., SCBA surveillance and maintenance records, and personnel qualification, training, and readiness.
- Problem identification and resolution for airborne radioactivity control and mitigation. The inspectors reviewed audits, self-assessments, and corrective action documents to verify problems were being identified and properly addressed for resolution.
These activities constitute completion of the four required samples of in-plant airborne radioactivity control and mitigation program, as defined in Inspection Procedure 71124.03.
b. Findings
No findings were identified.
2RS7 Radiological Environmental Monitoring Program
a. Inspection Scope
The inspectors evaluated whether the licensees radiological environmental monitoring program quantified the impact of radioactive effluent releases to the environment and sufficiently validated the integrity of the radioactive gaseous and liquid effluent release program. The inspectors also verified that the licensee continued to implement the voluntary Nuclear Energy Institute (NEI)/Industry Groundwater Protection Initiative. The inspectors reviewed or observed the following items:
- The inspectors observed selected air sampling and dosimeter monitoring stations, sampler station modifications, and the collection and preparation of environmental samples. The inspectors reviewed calibration and maintenance records for selected air samplers, composite water samplers, environmental sample radiation measurement instrumentation, and inter-laboratory comparison program results. The inspectors reviewed selected events documented in the annual environmental monitoring report and significant changes made by the licensee to the offsite dose calculation manual, as the result of changes to the land census. The inspectors evaluated the operability, calibration, and maintenance of meteorological instruments and assessed the meteorological dispersion and deposition factors. The inspectors verified the licensee had implemented sampling and monitoring program sufficient to detect leakage from structures, systems, or components with credible mechanism for licensed material to reach groundwater and reviewed changes to the licensees written program for identifying and controlling contaminated spills/leaks to groundwater.
- Groundwater protection initiative implementation, including assessment of groundwater monitoring results, identified leakage or spill events and entries made into 10 CFR 50.75
- (g) records, licensee evaluations of the extent of the contamination and the radiological source term, and reports of events associated with spills, leaks, and groundwater monitoring results.
- Problem identification and resolution for the radiological environmental monitoring program. The inspectors reviewed audits, self-assessments, and corrective action program documents to verify problems were being identified and properly addressed for resolution.
These activities constitute completion of the three required samples of radiological environmental monitoring program, as defined in Inspection Procedure 71124.07.
b. Findings
No findings were identified.
OTHER ACTIVITIES
Cornerstones: Initiating Events, Mitigating Systems, Barrier Integrity, Emergency Preparedness, Public Radiation Safety, Occupational Radiation Safety, and Security
4OA1 Performance Indicator Verification
.1 Unplanned Scrams per 7000 Critical Hours (IE01)
a. Inspection Scope
The inspectors reviewed licensee event reports for the period of October 2015 through December 31, 2016, to determine the number of scrams that occurred. The inspectors compared the number of scrams reported in these licensee event reports to the number reported for the performance indicator. The inspectors used definitions and guidance contained in NEI Document 99-02, Regulatory Assessment Performance Indicator Guideline, Revision 7, to determine the accuracy of the data reported.
These activities constituted verification of the unplanned scrams per 7000 critical hours performance indicator for Units 1 and 2, as defined in Inspection Procedure 71151.
b. Findings
No findings were identified.
.2 Unplanned Power Changes per 7000 Critical Hours (IE03)
a. Inspection Scope
The inspectors reviewed operating logs, corrective action program records, and monthly operating reports for the period of October 2015 through December 31, 2016, to determine the number of unplanned power changes that occurred. The inspectors compared the number of unplanned power changes documented to the number reported for the performance indicator. The inspectors used definitions and guidance contained in NEI Document 99-02, Regulatory Assessment Performance Indicator Guideline, Revision 7, to determine the accuracy of the data reported.
These activities constituted verification of the unplanned power changes per 7000 critical hours performance indicator for Units 1 and 2, as defined in Inspection Procedure 71151.
b. Findings
No findings were identified.
.3 Unplanned Scrams with Complications (IE04)
a. Inspection Scope
The inspectors reviewed the licensees basis for including or excluding in this performance indicator each scram that occurred between October 2015 and December 31, 2017. The inspectors used definitions and guidance contained in NEI Document 99-02, Regulatory Assessment Performance Indicator Guideline, Revision 7, to determine the accuracy of the data reported.
These activities constituted verification of the unplanned scrams with complications performance indicator for Units 1 and 2, as defined in Inspection Procedure 71151.
b. Findings
No findings were identified.
.4 Occupational Exposure Control Effectiveness (OR01)
a. Inspection Scope
The inspectors verified that there were no unplanned exposures or losses of radiological control over locked high radiation areas and very high radiation areas during the period of October 1, 2016, to March 31, 2017. The inspectors reviewed a sample of radiologically controlled area exit transactions showing exposures greater than 100 mrem. The inspectors used definitions and guidance contained in NEI Document 99-02, Regulatory Assessment Performance Indicator Guideline, Revision 7, to determine the accuracy of the reported data.
These activities constitute verification of the occupational exposure control effectiveness performance indicator, as defined in Inspection Procedure 71151.
b. Findings
No findings were identified.
.5 Radiological Effluent Technical Specifications (RETS)/Offsite Dose Calculation Manual
(ODCM) Radiological Effluent Occurrences (PR01)
a. Inspection Scope
The inspectors reviewed corrective action program records for liquid or gaseous effluent releases that occurred between October 1, 2016, and March 31, 2017, and were reported to the NRC to verify the performance indicator data. The inspectors used definitions and guidance contained in NEI Document 99-02, Regulatory Assessment Performance Indicator Guideline, Revision 7, to determine the accuracy of the reported data.
These activities constituted verification of the radiological effluent technical specifications (RETS)/ODCM radiological effluent occurrences performance indicator, as defined in Inspection Procedure 71151.
b. Findings
No findings were identified.
4OA2 Problem Identification and Resolution
Routine Review
a. Inspection Scope
Throughout the inspection period, the inspectors performed daily reviews of items entered into the licensees corrective action program and periodically attended the licensees condition report screening meetings. The inspectors verified that licensee personnel were identifying problems at an appropriate threshold and entering these problems into the corrective action program for resolution. The inspectors verified that the licensee developed and implemented corrective actions commensurate with the significance of the problems identified. The inspectors also reviewed the licensees problem identification and resolution activities during the performance of the other inspection activities documented in this report.
b. Findings
No findings were identified.
4OA3 Follow-up of Events and Notices of Enforcement Discretion
Event Follow-up for Forced Shutdown Due to Large Open Loop Cooling Pipe Break
a. Inspection Scope
On March 17, 2017 at 06:03 a.m., while at 100 percent power, Unit 1 experienced a sudden low alarm for the open loop cooling system. Operations had been monitoring leakage from the open loop piping system through several operational decision making (ODMIs) monitoring plans that supported continued operation via shiftly monitoring, leakage trigger points for actions and decisions, as well as operations contingencies for catastrophic failure. The open loop cooling system supplies cooling water to nonsafety-related heat exchangers and coolers in the turbine building, as well as facilitating low level radioactive waste discharge. Operations followed off-normal procedures and commenced a rapid shutdown at 06:08 a.m. Unit 1 entered Mode 3 at 09:01 a.m., all control rods were inserted into the reactor core and all safety-related systems functioned as designed.
The resident inspectors responded to the control room and observed the shutdown evolution and the operating crews performance, and also reviewed the licensees initial investigation. Furthermore, the residents walked down the site looking for effects from the massive water leak. The inspectors also reviewed and verified licensee met reporting requirements specified in NUREG-1022, Event Reporting Guidelines, Revision 3.
b. Findings
No findings were identified.
4OA5 Other Activities
.1 Temporary Instruction (TI) 2515/192, Inspection of the Licensees Interim Compensatory
Measures Associated with the Open Phase Condition Design Vulnerabilities in Electric Power Systems
a. Inspection Scope
The objective of this performance based temporary instruction is to verify implementation of interim compensatory measures associated with an open phase condition design vulnerability in electric power system for operating reactors. The inspectors conducted an inspection to determine if the licensee had implemented the following interim compensatory measures. These compensatory measures are to remain in place until permanent automatic detection and protection schemes are installed and declared operable for open phase condition design vulnerability. The inspectors verified the following:
- The licensee identified and discussed with operations staff the lessons-learned from the open phase condition events at U.S. operating plants, including the Byron Station open phase conditions and its consequences. This included conducting operator training for promptly diagnosing, recognizing consequences, and responding to an open phase condition.
- The licensee updated plant operating procedures to help operators promptly diagnose and respond to open phase condition on off-site power sources credited for safe shutdown of the plant.
- The licensee established and continued to implement periodic walk-down activities to inspect switchyard equipment, such as insulators, transmission line, and transformer connections associated with the off-site power circuits to detect a visible open phase condition.
- The licensee ensured that routine maintenance and testing activities on switchyard components have been implemented and maintained. As part of the maintenance and testing activities, the licensee assessed and managed plant risk in accordance with 10 CFR 50.65(a)(4) requirements.
b. Findings
No findings were identified.
The inspectors had the following observations related to the licensees interim compensatory measures:
- In a letter to the NRC, dated October 25, 2012, South Texas Project (STP)informed the NRC that they were vulnerable to an open phase condition. Since then, STP performed additional analysis using E-Tap analysis software and concluded that their electrical system design was not susceptible to the adverse consequences of an open phase condition. Therefore, they have implemented limited compensatory measures.
- Although the training mentioned the symptoms and effects of the open phase condition, it did not include operator training for promptly diagnosing, recognizing consequences, and responding to an open phase condition.
- The licensee updated plant operating procedures, but the changes were limited to guidance to measure all three phases of voltage on the engineered safety features buses and to conduct visual inspections of the switchyards, including transformers and connections. There was no guidance to help operators promptly diagnose and respond to open phase conditions on off-site power sources credited for safe shutdown of the plant.
- Although the licensee had implemented periodic walk-downs of the switchyard equipment, there was no specific guidance on what the operators should be looking for or how to perform the inspections. No training documents were provided that indicated personnel had received training on how to perform this task.
The licensee initiated Condition Report 17-1004 to capture the NRC observations; however, the only action specified was limited to evaluating if training should be provided to departments outside of operations.
.2 Review of the Implementation of the Industry Groundwater Protection Voluntary Initiative
a. Inspection Scope
The inspectors reviewed the licensees groundwater protection program to determine whether the licensee implemented NEI 07-07, Industry Groundwater Protection Initiative, dated August 2007. The inspectors interviewed personnel, performed walk-downs of selected areas, and reviewed the following three recent spill events:
- November 30, 2016: A 200-gallon spill of water, with a concentration of approximately 2,600 picocuries per liter (pCi/l) of tritium, on the owner controlled area (total tritium activity of 2.0E-6 Ci)
- January 14, 2017: A 4500-gallon leak of reservoir water, with a concentration of approximately 10,600 pCi/l of tritium, through a damaged underground pipe (total tritium activity of 1.8E-4 Ci)
- March 17, 2017: A 4.5 million-gallon spill of reservoir water, with a concentration of approximately 10,600 pCi/l of tritium, as a result of the catastrophic failure of the damaged pipe from January 14 (total tritium activity of 1.8E-1 Ci)b. Observations and Assessments The inspectors determined that none of the three spill events had radioactivity in excess of 20,000 pCi/l tritium and that no other radioactivity was detected. The inspectors also determined that STP did not notify the NRC or the State of Texas, formally or informally, of any of the three spill events.
The licensee is expected to follow the guidelines of the voluntary initiative described in NEI 07-07 for reporting and evaluating spills, leaks, and groundwater concerns.
Section 2.2, Voluntary Communication, of NEI 07-07 states:
Make informal communication as soon as practicable to appropriate State/Local officials, with follow-up notification to the NRC, as appropriate, regarding significant on-site leaks/spills into ground water and on-site or off-site water sample results exceeding the criteria in the radiological environmental monitoring program described in the offsite dose calculation manual.
The guidance in NEI 07-07 provides a threshold for this informal communication to State/Local officials of spills or leaks exceeding 100 gallons from a source containing licensed material. The guidance also recognizes that some states may require different communication thresholds, but specifies that the licensee shall document any agreements with State/Local officials that differ from the industry guidance.
Licensee Procedure 0PGP03-ZO-0053, Radiological Ground Water Protection Program, provides guidance for documenting and evaluating spills, leaks, or activities that may have released plant-related radionuclides and radioactive materials into the ground or subsurface. Addendum 1 of the procedure documents the licensees communication protocol for reporting spills and leaks to the state and the NRC.
According to the licensees procedure, they would not report a leak or spill to the NRC or the state informally or formally unless radioactivity in a sample was in excess of 20,000 picocuries/liter (pCi/l) tritium.
When asked the basis for the reporting criteria in Procedure 0PGP03-ZO-0053, the licensee stated it was based on a 2006 conversation with the State of Texas and STP.
During this conversation, it was agreed that without some activity level associated with the 100-gallon volume, this reporting would not mean much to them; Texas verbally recommended against informal reporting based merely on a volume. This resulted in an informal agreement on the spill criteria above.
However, the inspectors determined that the licensee did not have a documented mutual agreement with the State of Texas regarding Section 2.2 of NEI 07-07. In addition, the inspectors verified with the State of Texas that they did not have an agreement with STP regarding exceptions to the voluntary communications protocol in NEI 07-07.
The licensee entered this issue in their corrective action program as Condition Report 17-13531, to evaluate their agreement with the State of Texas and whether this verbal agreement meets Section 2.2 of NEI 07-07.
c. Findings
No findings were identified.
4OA6 Meetings, Including Exit
Exit Meeting Summary
On January 12, 2017, the inspectors presented the radiation safety inspection results to Mr. G. Powell, Executive Vice President and Chief Nuclear Officer, and other members of the licensee staff. The licensee acknowledged the issues presented. The licensee confirmed that any proprietary information reviewed by the inspectors had been returned or destroyed.
On January 23, 2017, the inspector presented the final inspection results of Temporary Instruction 2515/192 to Mr. G. Powell, Executive Vice President and Chief Nuclear Officer, and other members of the licensee staff. The licensee acknowledged the issues presented. No proprietary information was identified.
On March 31, 2017, the inspectors presented the radiation safety inspection results to Mr. G. Powell, Executive Vice President and Chief Nuclear Officer, and other members of the licensee staff. The licensee acknowledged the issues presented. The licensee confirmed that any proprietary information reviewed by the inspectors had been returned or destroyed.
On April 6, 2017, the inspectors presented the inspection results to Mr. D. Koehl, President and Chief Executive Officer, and other members of the licensee staff. The licensee acknowledged the issues presented. The licensee confirmed that any proprietary information reviewed by the inspectors had been returned or destroyed.
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee Personnel
- R. Aguilera, Manager, Plant Protection/Emergency Response
- M. Berg, Manager, Design Engineering
- J. Berrio, Manager, Operations, Production Support & Programs
- C. Bowman, Manager, Nuclear Support
- W. Brost, Engineer III
- A. Capristo, Executive Vice President and Chief Administrative Officer
- D. Caraballo, Engineer, Systems Engineering
- J. Connolly, Site Vice President
- A. Culver, Supervisor, Operations Training
- R. Dunn Jr., Manager, Nuclear Fuel and Analysis
- S. Feemster, Instructor
- T. Frawley, Manager, Corporate Projects
- C. Gann, Manager, Employee Concerns Program
- C. Georgeson, Supervisor, Electrical Design
- R. Gibbs, Manager, Operations Division, Unit Operations
- R. Gonzales, Senior Licensing Engineer
- G. Hildebrandt, Manager, Training
- D. Hubenak, Supervisor, General Health Physics
- R. Hubenak, Supervisor, Training
- G. Janak, Operations Training Manager
- B. Jefferson, Director, Operations
- D. Kappler, Health Physicist, Radiation Protection
- K. Kawabata, Health Physicist
- B. Lane, Manager, Operations Division, Integrated Work Management & Outage
- J. Lovejoy, Manager, I&C Maintenance
- E. Matejceck, Manager, Mechanical Maintenance
- R. McNeil, Manager, Maintenance Engineering
- J. Mertink, Manager, Nuclear Oversight
- J. Milliff, Manager, Security
- M. Murray, Manager, Regulatory Affairs
- K. Nigmatullina, Effluent Primary Chemist, Chemistry
- M. Page, General Manager, Engineering
- C. Pence, Manager, Chemistry
- L. Peter, General Manager, Projects
- J. Pointon, Supervisor, ALARA
- G. Powell, Executive Vice President and Chief Nuclear Officer
- D. Rencurrel, Senior Vice President, Operations
- M. Ruvalcaba, Manager, Strategic Projects
- R. Savage, Engineer, Licensing Consult Specialist
- R. Scarborough, Manager, Operations Training Mentor
- M. Schaefer, Plant General Manager
- R. Stastny, Maintenance Manager
- L. Sterling, Supervisor, Licensing
- L. Stoicescu, Health Physicist, Radiological Environmental Monitoring Program
- C. Stone, Manager, Health Physics
- P. Travis, Supervisor, Environmental
- M. Veliz, System Engineer
- J. Von Suskil, Owner Rep - NRG South Texas LP
- K. Wallis, Acting Manager, Systems Engineering
- R. Wied, Respiratory Support, Radiation Protection
- D. Zink, Supervising Engineering Specialist
LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED
Closed
Inspection of the Licensees Interim Compensatory Measures 2515/192 TI Associated with the Open Phase Condition Design Vulnerabilities in Electric Power Systems