IR 05000261/2019003
| ML19318F778 | |
| Person / Time | |
|---|---|
| Site: | Robinson  |
| Issue date: | 11/14/2019 |
| From: | Randy Musser NRC/RGN-II/DRP/RPB3 |
| To: | Kapopoulos E Duke Energy Progress |
| A. Wilson RGN-II/DRP | |
| References | |
| IR 2019003 | |
| Download: ML19318F778 (10) | |
Text
ber 14, 2019
SUBJECT:
H.B. ROBINSON STEAM ELECTRIC PLANT - INTEGRATED INSPECTION REPORT 05000261/2019003
Dear Mr. Kapopoulos:
On September 30, 2019, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at H.B. Robinson Steam Electric Plant. On October 16, 2019, the NRC inspectors discussed the results of this inspection with Ms. Nicole Flippin, General Plant Manager, and other members of your staff. The results of this inspection are documented in the enclosed report.
No NRC-identified or self-revealing findings were identified during this inspection.
A licensee-identified violation which was determined to be of very low safety significance is documented in this report. We are treating this violation as a non-cited violation (NCV)
consistent with Section 2.3.2 of the Enforcement Policy.
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/
Randall A. Musser, Chief Reactor Projects Branch 3 Division of Reactor Projects Docket No. 05000261 License No. DPR-23
Enclosure:
As stated
Inspection Report
Docket Number: 05000261 License Number: DPR-23 Report Number: 05000261/2019003 Enterprise Identifier: I-2019-003-0017 Licensee: Duke Energy Progress, LLC Facility: H.B. Robinson Steam Electric Plant Location: 3581 West Entrance Road, Hartsville SC 29550 Inspection Dates: July 1, 2019 to September 30, 2019 Inspectors: A. Beasten, Resident Inspector M. Fannon, Senior Resident Inspector Pwr/Tl Approved By: Randall A. Musser, Chief Reactor Projects Branch 3 Division of Reactor Projects Enclosure
SUMMARY The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at H.B. Robinson Steam Electric Plant in accordance with the Reactor Oversight Process. The Reactor Oversight Process is the NRCs program for overseeing the safe operation of commercial nuclear power reactors. Refer to https://www.nrc.gov/reactors/operating/oversight.html for more information. A licensee-identified non-cited violation is documented in report section: 71111.06.
List of Findings and Violations No findings or violations of more than minor significance were identified.
Additional Tracking Items None.
PLANT STATUS Unit 2 began the inspection period at rated thermal power. On August 11, 2019, the unit experienced an automatic reactor trip and turbine trip due to an electrical fault in the main generator exciter. The unit was restarted on September 3, 2019 and was returned to rated thermal power on September 6, 2019. The unit remained at or near rated thermal power for the remainder of the inspection period.
INSPECTION SCOPES Inspections were conducted using the appropriate portions of the inspection procedures (IPs) in effect at the beginning of the inspection unless otherwise noted. Currently approved IPs with their attached revision histories are located on the public website at http://www.nrc.gov/reading-rm/doc-collections/insp-manual/inspection-procedure/index.html. Samples were declared complete when the IP requirements most appropriate to the inspection activity were met consistent with Inspection Manual Chapter (IMC) 2515, Light-Water Reactor Inspection Program - Operations Phase. The inspectors performed plant status activities described in IMC 2515 Appendix D, Plant Status and conducted routine reviews using IP 71152, Problem Identification and Resolution. The inspectors reviewed selected procedures and records, observed activities, and interviewed personnel to assess licensee performance and compliance with Commission rules and regulations, license conditions, site procedures, and standards.
REACTOR SAFETY 71111.01 - Adverse Weather Protection Impending Severe Weather Sample (IP Section 03.03) (1 Sample)
(1) The inspectors evaluated readiness for impending adverse weather related to Hurricane Dorian on September 1 through September 5, 2019 External Flooding Sample (IP Section 03.04) (1 Sample)
(1) The inspectors evaluated readiness to cope with external flooding on August 28, 2019
- Lake Robinson dam and spillway tainter gates 71111.04Q - Equipment Alignment Partial Walkdown Sample (IP Section 03.01) (4 Samples)
(1) Spent fuel pool cooling, including service water pumps 'C' and 'D' and 'A' component cooling water pump, for less than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> time to boil on July 10, 2019 (2) Steam driven auxiliary feedwater system during the 'B' motor driven auxiliary feedwater train maintenance outage on July 17, 2019 (3) Dedicated shutdown emergency diesel generator following the turbine and reactor trip on August 13 through 15, 2019 (4) Emergency bus E-1 equipment and components while the dedicated shutdown diesel generator was out of service for planned overhaul on August 20, 2019
71111.05A - Fire Protection (Annual)
Annual Inspection (IP Section 03.02) (1 Sample)
(1) The inspectors evaluated fire brigade performance on August 9, 2019 71111.05Q - Fire Protection Quarterly Inspection (IP Section 03.01) (5 Samples)
(1) Fire zone 2, 'A' emergency diesel generator room, on July 2, 2019 (2) Fire zone 3, safety injection pump room, on August 2, 2019 (3) Fire zone 21, rod control room, on August 2, 2019 (4) Fire zone 4, charging pump room, on August 6, 2019 (5) Fire zone 8, boron injection tank room, on August 27, 2019 71111.06 - Flood Protection Measures Inspection Activities - Underground Cables (IP Section 02.02c.) (1 Sample)
(1) (1) M-50A and M-50B, on June 18, 2019 (2) M-35 and M-36, on June 18, 2019 71111.07A - Heat Sink Performance Annual Review (IP Section 02.01) (1 Sample)
(1) The 'A' component cooling water heat exchanger 71111.11Q - Licensed Operator Requalification Program and Licensed Operator Performance Licensed Operator Performance in the Actual Plant/Main Control Room (IP Section 03.01)
(1 Sample)
(1) The inspectors observed and evaluated licensed operator performance in the control room during plant startup activities on September 3, 2019 71111.12 - Maintenance Effectiveness Routine Maintenance Effectiveness Inspection (IP Section 02.01) (2 Samples)
(1) Dedicated shutdown diesel generator following recent overhaul (2) Water cooled condensing unit '1B' following recent failure 71111.13 - Maintenance Risk Assessments and Emergent Work Control Risk Assessment and Management Sample (IP Section 03.01) (4 Samples)
(1) 'B' motor driven auxiliary feedwater system train maintenance outage on July 17, 2019
(2) Maintenance activities for the week of August 18, 2019, including the dedicated shutdown diesel generator overhaul (3) Steam driven auxiliary feedwater system planned maintenance concurrent with MST-021, Reactor Protection Logic Testing Train B, and MST-023, Safeguard Relay Rack Train B, testing on September 10, 2019 (4) 230kV switchyard relay calibrations for the week of September 16, 2019 71111.15 - Operability Determinations and Functionality Assessments Operability Determination or Functionality Assessment (IP Section 02.02) (5 Samples)
(1) Nuclear condition report (NCR) 2281205, 'A' safety injection pump seal water line vibrations on July 10, 2019 (2) NCR 2266397, 'B' emergency pressurization failing to meet acceptance criteria for control room envelope on July 31, 2019 (3) NCR 2277990, underground cable vault M-36 water level above grating and on cables on July 31, 2019 (4) NCR 2283402, debris found in motor vent screen of 'C' service water pump on August 2, 2019 (5) NCR 2283172, 'A' diesel generator air compressor unloader tower porting off air on August 6, 2019 71111.19 - Post-Maintenance Testing Post-Maintenance Test Sample (IP Section 03.01) (5 Samples)
(1) Work order (WO) 20224292, 'B' motor driven auxiliary feedwater train maintenance outage on July 17, 2019 (2) OST-908-4, Component Cooling Water Pump Test 'C', following planned maintenance on the 'C' component cooling water pump on July 25, 2019 (3) OP-306, Component Cooling Water System, following minor maintenance on the
'A' component cooling water pump on July 31, 2019 (4) OP-602-1, DSDG Power Pack Replacement Break-In and Testing, following major planned maintenance on August 23, 2019 (5) WO 20240431, replace open limit switch on FCV-113A-LS-O, and WO 20240426, replace open limit switch on FCV-113A-LS-C, on September 16, 2019 71111.22 - Surveillance Testing Surveillance Tests (other) (IP Section 03.01) (2 Samples)
(1) OST-108-1, Boric Acid Pump 'A' Inservice Test, on July 8, 2019 (2) SP-1506, Control Room Integrated In-Leakage Tracer Test, performed from March 28-31, 2019, however the final report from the vendor was not issued until July, 2019 Inservice Testing (IP Section 03.01) (1 Sample)
(1) OST-151-3, Safety Injection Subsystem Components Test Pump 'C', on September 23, 2019
OTHER ACTIVITIES - BASELINE 71151 - Performance Indicator Verification IE01: Unplanned Scrams per 7000 Critical Hours Sample (IP Section 02.01) (1 Sample)
(1) Unplanned scrams from July 1, 2018 to June 30, 2019 IE03: Unplanned Power Changes per 7000 Critical Hours Sample (IP Section 02.02) (1 Sample)
(1) Unplanned power changes from July 1, 2018 to June 30, 2019 MS08: Heat Removal Systems (IP Section 02.07) (1 Sample)
(1) Heat removal systems (MS08) from July 1, 2018 to June 30, 2019 BI01: Reactor Coolant System (RCS) Specific Activity Sample (IP Section 02.10) (1 Sample)
(1) RCS activity (B101) from July 1, 2018 to June 30, 2019 71152 - Problem Identification and Resolution Annual Follow-up of Selected Issues (IP Section 02.03) (2 Samples)
(1) NCR 2253155, Steam dumps group 1 loss of power MST-021 NCR 2147971, Bank 1 steam dump loss of indication (2) NCR 2256141, FCV-1424 remains open after stopping 'A' motor driven auxiliary feedwater pump 71153 - Followup of Events and Notices of Enforcement Discretion Personnel Performance (IP Section 03.03) (1 Sample)
(1) The inspectors evaluated the licensees performance in response to a Unit 2 automatic reactor trip from rated thermal power due to a turbine trip that was a result of a fault in the main generator exciter on August 11, 2019. A non-emergency event report was submitted to the NRC (Event Notification 54212). The reactor trip was not complex, with all systems responding normally post trip. The unit was restarted on September 3, 2019 and was returned to rated thermal power on September 6, 2019. The issue was placed in the corrective action program as NCR 2286376.
INSPECTION RESULTS Licensee-Identified Non-Cited Violation 71111.06 This violation of very low safety significance was identified by the licensee and has been entered into the licensee corrective action program and is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
Violation: Title 10 of CFR Part 50, Appendix B, Criterion III, Design Control, requires, in part, that that measures shall be established to assure applicable regulatory requirements and the design basis, as defined in section 50.2 and as specified in the license applications, for those structures, systems, and components to which this appendix applies are correctly translated into specifications, drawings, procedures, and instructions.
Contrary to the above, from June 18, 2018 to June 19, 2019, the licensee failed to maintain Class 1E (safety-related) electrical cables in an environment for which they are designed. Specifically, the low-voltage safety related cables associated with the A and B service water pumps and power and limit switches were submerged in water, a condition for which they are not qualified. The licensee took immediate actions to lower the water levels in underground cable vaults where submerged cables were discovered and conduct pump-downs of the safety-related underground cable vaults on an increased scheduled frequency.
Significance/Severity: Green. This performance deficiency was associated with the Mitigating Systems Cornerstone. The performance deficiency was related to the equipment reliability attribute and failure to maintain the cables in the environment for which they were designed adversely impacted the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, the submergence of the safety-related cables adversely impacted the service life of the cables and could cause the A train service water system to be inoperable in the event a cable failed as a result of continuous submergence. The finding screened as having very low safety significance (Green) because it did not represent an actual loss of function in the service water system.
Corrective Action References: This issue was being tracked in the licensees corrective action program by NCR 02277990.
Observation: Observation 71152 The Inspectors reviewed the licensees response to a relay failure of the A motor driven auxiliary feedwater (MDAFW) pump discharge flow control valve, NCR 02256147. On February 5, 2019, following post-maintenance testing on the A MDAFW pump, FCV-1424 failed to close as expected when the pump was secured. FCV-1424 is a discharge flow control valve that adjusts the flow from the MDAFW pump to the steam generators. The failure was unrelated to maintenance activities that had occurred earlier that day. Troubleshooting identified that the relay did not open when de-energized. Following relay replacement, all tests were completed successfully.
The Inspectors questioned the licensees investigation into the failure. The relay was to be sent offsite for failure analysis, however an onsite visual inspection was determined to be sufficient. The inspection revealed that the number 2 normally closed contact was bent which caused the relay to bind internally. The licensee concluded that the relay had been installed with the bent contact bar and was therefore a manufacturing defect. No extent of condition
was performed as it was determined to be an isolated failure. Although this relay had been purchased with 10 others from Westinghouse, the licensee had not notified Westinghouse of the defect. Additionally, the other 10 relays had not been located or inspected.
Based on these inspector questions, NCR 02277990 was reopened on April 3, 2019, and the failure cause was changed to inadequate relay installation. Although the installation procedure contained instructions to verify that the contacts were aligned correctly both prior to and after installation, the licensee initiated a procedure revision to clarify that all contacts and should be inspected both before and after installation. Given this new information, the inspectors questioned how the defect was introduced. The licensee maintained that it had been installed with the defect. The inspectors also questioned the capability of the A MDAFW pump to perform its intended safety function with a defective relay installed in the system. The licensee maintained that the pump would perform its safety function since the internal binding from the bent contact bar would not have prevented the relay from energizing, and valve FCV-1424 would have performed its safety function. The inspectors questioned the licensees operability conclusions given only a visual examination of the relay and inquired to the status of the other 10 relays received in the same purchase order. An extent of condition was performed on the B MDAFW pump and no issues were noted on that relay. Work orders have been initiated to inspect the remaining relays installed in the plant.
In response to additional inspector questions, the licensee sent the relay out for forensic testing in May, 2019. The testing could not replicate the failure, however there was evidence of gouge marks on the bent contact that could have been caused by a screwdriver or other tool used during installation. Based on the results of the forensics testing, the inspectors concluded the licensees determination that the A MDAFW pump would have performed its safety function was adequate. While the licensees final corrective actions were adequate, the inspectors determined that the initial cause evaluation and investigative process lacked technical rigor. The initial failure determination (manufacturing defect) proved to be incorrect and was not challenged internally so no initial extent of condition was performed, and the defective relay was replaced without further investigation or corrective action. Through inspector follow-up the licensee subsequently applied the appropriate level of technical rigor to the investigation.
EXIT MEETINGS AND DEBRIEFS The inspectors confirmed that proprietary information was controlled to protect from public disclosure.
- On October 16, 2019, the inspectors presented the integrated inspection results to Ms. Nicole Flippin, General Plant Manager, and other members of the licensee staff.
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