IR 05000390/2013007
| ML13098B025 | |
| Person / Time | |
|---|---|
| Site: | Watts Bar  |
| Issue date: | 04/08/2013 |
| From: | Hopper G Reactor Projects Branch 7 |
| To: | James Shea Tennessee Valley Authority |
| References | |
| IR-13-007 | |
| Download: ML13098B025 (22) | |
Text
UNITED STATES pril 8, 2013
SUBJECT:
WATTS BAR NUCLEAR PLANT, UNIT 1 - NRC PROBLEM IDENTIFICATION AND RESOLUTION INSPECTION REPORT 05000390/2013007
Dear Mr. Shea:
On February 22, 2013, the U. S. Nuclear Regulatory Commission (NRC) completed an inspection at your Watts Bar Nuclear Plant, Unit 1. The enclosed report documents the inspection findings, which were discussed on February 22, 2013, with Mr. Timothy Cleary and other members of your staff.
The inspection was an examination of activities conducted under your license as they relate to the identification and resolution of problems, and compliance with the Commissions rules and regulations and with the conditions of your operating license. Within these areas, the inspection involved examination of selected procedures and representative records, observations of plant equipment and activities, and interviews with personnel.
Based on the inspection sample, the inspection team concluded that the implementation of the corrective action program and overall performance related to identifying, evaluating, and resolving problems at Watts Bar Nuclear Plant was adequate. Licensee identified problems were entered into the corrective action program at an appropriate threshold. Problems were generally prioritized and evaluated commensurate with the safety significance of the problems.
Corrective actions were generally implemented in a timely manner commensurate with their importance to safety and addressed the identified causes of problems. Lessons learned from the industry operating experience were generally reviewed and applied when appropriate.
Audits and self-assessments were effectively used to identify problems and appropriate actions.
One NRC identified finding of very low safety significance (Green) was identified during this inspection. The finding did not involve a violation of NRC requirements. If you disagree with the crosscutting aspect assigned to the finding in this report, you should provide a response within 30 days of the date of this inspection report, with the basis for your disagreement to the Regional Administrator, RII, and the NRC Senior Resident Inspector at the Watts Bar Nuclear Plant, Unit 1. In accordance with 10 CFR 2.390 of the NRCs 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 the NRCs 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/
George T. Hopper, Chief Reactor Projects Branch 7 Division of Reactor Projects Docket No.: 50-390 License No.: NPF-90
Enclosure:
Inspection Report 05000390/2013007 w/Attachment: Supplemental Information
REGION II==
Docket No.: 50-390 License No.: NPF-90 Report No.: 05000390/2013007 Licensee: Tennessee Valley Authority (TVA)
Facility: Watts Bar Nuclear Plant, Unit 1 Location: Spring City, TN Dates: February 04 - 08, 2013 February 19 - 22, 2013 Inspectors: N. Staples, Sr. Project Inspector (Team Leader)
S. Ninh, Sr. Project Engineer T. Vukovinsky, Reactor Inspector R. Williams, Reactor Inspector Approved by: George T. Hopper, Chief Reactor Projects Branch 7 Division of Reactor Projects
SUMMARY OF FINDINGS
IR 05000390/2013007; February 04 - 22, 2013; Watts Bar Nuclear Plant, Unit 1; biennial inspection of the identification and resolution of problems.
The inspection was conducted by a senior project inspector, a senior project engineer and two reactor inspectors. One NRC-identified finding of very low safety significance was identified.
The significance of most findings is indicated by their color (Green, White, Yellow, Red) using Inspection Manual Chapter (IMC) 0609, Significance Determination Process (SDP). Findings for which the SDP does not apply may be Green or be assigned a severity level after NRC management review. The NRCs program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, Reactor Oversight Process.
Problem Identification and Resolution The inspectors concluded that, in general, problems were properly identified, evaluated, prioritized, and corrected. The licensee was generally effective at identifying problems and entering them into the corrective action program (CAP) for resolution. Generally, prioritization and evaluation of issues were adequate, formal root cause evaluations for significant problems, and corrective actions specified for problems were consistent with licensee CAP procedures.
Overall, corrective actions developed and implemented for issues were generally effective and implemented in a timely manner.
The inspectors determined that audits and self-assessments were adequate in identifying deficiencies and areas for improvement in the CAP, and appropriate corrective actions were developed to address the issues identified. Operating experience usage was found to be generally acceptable and integrated into the licensees processes for performing and managing work, and plant operations.
Based on discussions and interviews conducted with plant employees from various departments, the inspectors determined that personnel at the site felt free to raise safety concerns to management and use the CAP to resolve those concerns.
Cornerstone: Initiating Events
Green: Inspectors identified a finding of very low safety significance for failure to follow procedure BP-259, Oversight of Supplemental Personnel, Rev. 9. Specifically, during the licensees review of the vendor instructions for performing maintenance on turbine intercept valve 1-FCV-1-102, the licensee failed to recognize that the vendor instructions were not wholly applicable due to site-specific modifications made on the Electro Hydraulic Control (EHC)system. Consequently, an EHC system leak was identified on valve 1-FCV-1-102 during power ascension at 61% power that led to a manual turbine trip. The issue was entered into the licensees CAP program as Problem Evaluation Report (PER) 686688.
The finding was determined to be more than minor because it affected the design control attribute of the initiating events cornerstone objective to limit the likelihood of those events that upset plant stability and challenge critical safety functions during shutdown as well as power operations. Using the Inspection Manual Chapter 0609, Significance Determination Process,
Phase 1 worksheet, the finding was determined to have very low safety significance because the condition only affected the initiating events cornerstone and did not contribute to both the likelihood of a reactor trip and the likelihood that mitigation equipment or functions will not be available. The finding was determined to have a cross-cutting aspect in Human Performance,
Work Practices, in that the licensee did not ensure supervisory and management oversight of work activities, including contractors, such that nuclear safety is supported. (H.4(c)) (4OA2)
REPORT DETAILS
OTHER ACTIVITIES
4OA2 Problem Identification and Resolution
.1 Assessment of the Corrective Action Program
a. Inspection Scope
The inspectors reviewed the licensees Corrective Action Program (CAP) procedures which described the administrative process for initiating and resolving problems, primarily through the use of Problem Evaluation Reports (PERs). To verify that problems were being properly identified, appropriately characterized, and entered into the CAP, the inspectors reviewed PERs that had been issued between January 2011 and February 2013, including a detailed review of selected PERs associated with the following risk-significant systems: Residual Heat Removal (RHR), Emergency Diesel Generators (EDG), and Control Air. Where possible, the inspectors independently verified that the corrective actions were implemented as intended. The inspectors also reviewed selected common cause and generic concerns associated with root cause evaluations to determine if they had been appropriately addressed. The inspectors selected a representative number of PERs that were identified and assigned to the major plant departments, including operations, maintenance, engineering, health physics, chemistry, and security. These PERs were reviewed to assess each departments threshold for identifying and documenting plant problems, thoroughness of evaluations, and adequacy of corrective actions. The inspectors reviewed selected PERs, verified corrective actions were implemented, and attended meetings where PERs were screened for significance to determine whether the licensee was identifying, accurately characterizing, and entering problems into the CAP at an appropriate threshold.
The inspectors conducted plant walkdowns of equipment associated with the selected systems and other plant areas to assess the material condition and to look for any deficiencies that had not been previously entered into the CAP. The inspectors reviewed Service Requests (SR), PERs, maintenance history, completed work orders (WO) for the systems, and reviewed associated system health reports. These reviews were performed to verify that problems were being properly identified, appropriately characterized, and entered into the CAP. Items reviewed generally covered a two-year period of time; however, in accordance with the inspection procedure, a five-year review was performed for selected systems for age-dependent issues.
Control Room walk-downs were also performed to assess the main control room deficiency list and to ascertain if deficiencies were entered into the CAP and tracked to resolution. Operator workarounds (OWA) and operator burden screenings were reviewed, and the inspectors verified compensatory measures for deficient equipment which were being implemented in the field.
The inspectors conducted a detailed review of selected PERs to assess the adequacy of the root cause and apparent cause evaluations of the problems identified. The inspectors reviewed these evaluations against the descriptions of the problem described in the PERs and the guidance in licensee procedure NPG-SPP-03.1.6, Root Cause Analysis, Rev. 5 and NPG-SPP-03.1.5, Apparent Cause Evaluations, Rev. 5. The inspectors assessed if the licensee had adequately determined the cause(s) of identified problems, and had adequately addressed operability, reportability, common cause, generic concerns, extent-of-condition, and extent-of-cause. The review also assessed if the licensee had appropriately identified and prioritized corrective actions to prevent recurrence.
The inspectors reviewed selected industry operating experience (OE) items, including NRC generic communications, to verify that they had been appropriately evaluated for applicability and that issues identified through these reviews had been entered into the CAP.
The inspectors reviewed site trend reports, to determine if the licensee effectively trended identified issues and initiated appropriate corrective actions when adverse trends were identified.
The inspectors attended various plant meetings to observe management oversight functions of the corrective action process. These included PER screening meetings, Department Corrective Action Review Board (D-CARB), and the Corrective Action Review Board (CARB).
Documents reviewed are listed in the Attachment.
b. Assessment Identification of Issues The inspectors determined that the licensee was generally effective in identifying problems and entering them into the CAP and there was an appropriately low threshold for entering issues into the CAP. This conclusion was based on a review of the requirements for initiating SRs as described in licensee procedure NPG-SPP-01.14, Service Request Initiation, Rev. 3, and managements expectation that employees were encouraged to initiate SRs for any reason. Trending was generally effective in monitoring equipment performance. Site management was actively involved in the CAP and focused appropriate attention on significant plant issues. Based on reviews and walkdowns of accessible portions of the selected systems, the inspectors determined that system deficiencies were being identified and placed in the CAP.
The inspectors identified the following performance deficiencies. These issues were screened in accordance with Manual Chapter 0612, Issue Screening, and were determined to be of minor significance and not subject to enforcement action in accordance with the NRCs Enforcement Policy.
On February 12, 2013, the team identified a performance deficiency associated with the licensees failure to follow procedure NPG-SPP-03.1.5, Apparent Cause Evaluations, while performing the apparent cause evaluation (ACE) for PER 479167. Specifically, the licensee did not perform an adequate ACE in that the extent of condition (EOC) only looked at the impact of faulted indication lamps on the EDG system. The performance deficiency was considered minor because a subsequent EOC review did not identify any additional safety systems that could be affected by faulty indicating lamps. The licensee initiated SR 686694, ACE 479167 to address this issue. WBN also initiated SR 686693 to address the EOC for IN 94-68 at Watts Bar Nuclear, Sequoyah Nuclear Plant (SR 686696), and Browns Ferry Nuclear Plant (SR 686697).
On February 19, 2013, during system engineering walkdowns, inspectors identified a performance deficiency for not following procedural guidance for anchor point tie-offs.
Specifically, a Unit 2 worker had tied off to a 2 inch conduit for fall protection which was not allowed by procedure 305, Fall Protection Systems. This issue was considered minor because the individual did not challenge the anchor point and no other equipment was affected. PER 680160, U2 Worker Tied Off to two inch Conduit for Fall Protection, was initiated to evaluate what occurred on February 19, 2013, and to determine if any additional corrective actions were needed to address anchorage point tie-offs.
Prioritization and Evaluation of Issues Based on the review of PERs sampled by the inspection team during the onsite period, the inspectors concluded that problems were generally prioritized and evaluated in accordance with the licensees CAP procedures as described in the PER significance determination guidance in NPG-SPP-03.1.4, Corrective Action Program Screening and Oversight, Rev.0010. Each PER was assigned a priority level at the PER screening meeting, and adequate consideration was given to system or component operability and associated plant risk.
The inspectors determined that station personnel had conducted root cause and apparent cause analyses in compliance with the licensees CAP procedures and assigned cause determinations were appropriate, considering the significance of the issues being evaluated. A variety of formal causal-analysis techniques were used depending on the type and complexity of the issue consistent with NPG-SPP-03.1.6, Root Cause Analysis, Rev. 5 and NPG-SPP-03.1.5, Apparent Cause Evaluations, Rev. 5.
Effectiveness of Corrective Actions Based on a review of corrective action documents, interviews with licensee staff, and verification of completed corrective actions, the inspectors determined that, overall, corrective actions were timely, commensurate with the safety significance of the issues, and effective, in that conditions adverse to quality were corrected and non-recurring. For significant conditions adverse to quality, the corrective actions directly addressed the cause and effectively prevented recurrence in that a review of performance indicators, PERs, and effectiveness reviews demonstrated that the significant conditions adverse to quality had not recurred. Effectiveness reviews for corrective actions to prevent recurrence (CAPRs) were sufficient to ensure corrective actions were properly implemented and were effective.
c. Findings
Introduction:
Inspectors identified a Green finding (FIN) for failure to follow procedure BP-259, Oversight of Supplemental Personnel, Rev. 9. Specifically, the licensee did not recognize that the vendor instructions were not wholly applicable due to site-specific modifications made on the Electro Hydraulic Turbo-generator Controls (EHC) system.
Consequently, an EHC system leak was identified on valve 1-FCV-1-102 during power ascension at 61% power that led to a manual turbine trip. The issue was entered into the licensees CAP program as PER 686688.
Description:
Procedure BP-259 states that the Technical Contract Manager is, in part, responsible for ensuring supplemental (vendor) personnel procedures that perform work in the plant, are prepared, reviewed, revised and approved in accordance with procedure NPG-SPP-01.2, Administration of Site Technical Procedures. Procedure SPP-01.2, step 3.1.1.D, states in part, Review procedure prior to use to ensure that potential adherence problems are resolved. During the licensees review of the vendor instructions for performing maintenance on turbine intercept valve 1-FCV-1-102, the licensee failed to recognize that the vendor instructions were not wholly applicable due to site-specific modifications made on the EHC system. These modifications included the addition of vibration dampening tube support brackets. The vendor instructions did not contain specific steps for the removal of the support brackets nor for their reinstallation. Work was performed utilizing the vendor instructions on three separate occasions in 2006, 2008 and 2009. During one of these evolutions, the tube support brackets were removed but not reinstalled. Subsequently, on April 6, 2011 while performing extent-of-condition inspections initiated due to a prior unrelated EHC tubing failure, personnel noted in the work performed logs that the actuator support brackets on the EHC tubing for valve 1-FCV-1-102 were missing. This work order package was closed without reinstalling the missing support brackets. On May 22, 2011, a through-wall leak was identified on the EHC overspeed protection control tubing near the control block of 1-FCV-1-102. The leak worsened causing the governor and intercept valves to begin drifting closed. The operators commenced a power reduction to 49% power and then initiated a turbine trip, ultimately stabilizing at 6-10% reactor power. The reactor was not tripped due to power levels being below 50% prior to the turbine trip.
Analysis:
The licensees failure to adequately review the supplemental vendor procedures for work performed on the EHC system in accordance with site procedures was determined to be a performance deficiency. The inspectors determined that the finding was more than minor because it affected the design control attribute of the initiating events cornerstone objective to limit the likelihood of those events that upset plant stability and challenge critical safety functions during shutdown as well as power operations. Using the Inspection Manual Chapter 0609, Significance Determination Process, Phase 1 worksheet, the finding was determined to have very low safety significance because the condition only affected the initiating events cornerstone and did not contribute to both the likelihood of a reactor trip and the likelihood that mitigation equipment or functions would not be available.
The cause of this finding was directly related to the cross-cutting component of Work Practices in the Human Performance area, in that the licensee did not ensure supervisory and management oversight of work activities, including contractors, such that nuclear safety is supported. (H.4(c))
Enforcement:
Procedure BP-259 states that the Technical Contract Manager is, in part, responsible for ensuring supplemental (vendor) personnel procedures that perform work in plant, are prepared, reviewed, revised and approved in accordance with procedure NPG-SPP-01.2. Procedure NPG-SPP-01.2, step 3.1.1.D, states in part, Review procedure prior to use to ensure that potential adherence problems are resolved.
Contrary to this, on May 22, 2011, inspectors determined that WBN did not follow non-safety related procedure BP-259, in that, the licensee failed to recognize that the vendor instructions were not wholly applicable due to site-specific modifications made on the EHC system. The EHC system is not a safety-related component, procedure BP-259 is not a safety-related procedure, and this finding does not involve enforcement action because no violation of regulatory requirements was identified. Because this finding does not involve a violation and has very low safety significance, it is identified as a FIN.
(FIN 05000360/2013007-01, Failure to Follow Procedure BP-529 Oversight of Supplemental Personnel)
.2 Assessment of the Use of Operating Experience (OE)
a. Inspection Scope
The inspectors examined licensee programs for reviewing industry operating experience, reviewed licensee procedure NPG-SPP-02.3, Operating Experience Program, reviewed and selected PERs to assess the effectiveness of how external and internal operating experience data was handled at the plant. In addition, the inspectors selected a sample of OE documents (e.g., NRC generic communications, 10 CFR Part 21 reports, licensee event reports, vendor notifications, and plant internal operating experience items, etc.), which had been issued since January 2011 to verify whether the licensee had appropriately evaluated each notification for applicability and whether issues identified through these reviews were entered into the CAP. Documents reviewed are listed in the Attachment.
b. Assessment Based on a review of selected documentation related to operating experience issues, the inspectors determined that the licensee was generally effective in screening operating experience for applicability to the plant. Industry OE was evaluated at either the corporate or plant level depending on the source and type of the document.
Relevant information was then forwarded to the applicable department for further action or informational purposes. OE issues requiring action were entered into the CAP for tracking and closure. In addition, operating experience was included in all apparent cause and root cause evaluations in accordance with licensee procedure NPG-SPP-03.1 Corrective Action Program, Rev. 5.
c. Findings
No findings were identified.
.3 Assessment of Self-Assessments and Audits
a. Inspection Scope
The inspectors reviewed audit reports and self-assessment reports, including those which focused on problem identification and resolution, to assess the thoroughness and self-criticism of the licensee's audits and self assessments, and to verify that problems identified through those activities were appropriately prioritized and entered into the CAP for resolution in accordance with licensee procedure NPG-SPP-02.1, Self-Assessment and Benchmark Program, Rev. 0. Documents reviewed are listed in the Attachment.
b. Assessment The inspectors determined that the scopes of assessments and audits were adequate.
Self-assessments were generally detailed and critical, as evidenced by findings consistent with the inspectors independent review. The inspectors verified that PERs were created to document areas for improvement and findings resulting from the self-assessments, and verified that actions had been completed consistent with those recommendations. Generally, the licensee performed evaluations that were technically accurate. Site trend reports were thorough and a low threshold was established for evaluation of potential trends, as evidenced by the PERs reviewed that were initiated as a result of adverse trends.
c. Findings
No findings were identified.
.4 Assessment of Safety-Conscious Work Environment
a. Inspection Scope
The inspectors randomly interviewed 18 on-site workers regarding their knowledge of the corrective action program at Watts Bar Unit 1 and their willingness to write PERs or raise safety concerns. During technical discussions with members of the plant staff, the inspectors conducted interviews to develop a general perspective of the safety-conscious work environment at the site. The interviews were also conducted to determine if any conditions existed that would cause employees to be reluctant to raise safety concerns. The inspectors reviewed the licensees Employee Concerns Program (ECP) and interviewed the ECP coordinators. Additionally, the inspectors reviewed a sample of completed ECP reports to verify that concerns were being properly reviewed and identified deficiencies were being resolved and entered into the CAP when appropriate. Documents reviewed are listed in the Attachment.
b. Assessment Based on the interviews conducted and the PERs reviewed, the inspectors determined that licensee management emphasized the need for all employees to identify and report problems using the appropriate methods established within the administrative programs, including the CAP and ECP. These methods were readily accessible to all employees.
Based on discussions conducted with a sample of plant employees from various departments, the inspectors determined that employees felt free to raise issues, and that management encouraged employees to place issues into the CAP for resolution. The inspectors did not identify any reluctance on the part of the licensee staff to report safety concerns.
c. Findings
No findings were identified.
4OA3 Event Follow-up
.1 (Closed) Licensee Event Report (LER) 05000390/2012-005: Automatic Start of
Emergency Diesel Generators due to Failed Transfer of Power to 6.9kV Shutdown Board On October 16, 2012 at 2330 EDT, Watts Bar Nuclear Plant (WBN-1) licensed operators attempted a manual fast transfer of the 1 B-B 6.9kV Shutdown Board (SDBD) from the normal feeder breaker to the alternate feeder breaker. The transfer was not successful, resulting in the automatic start of the four emergency diesel generators. After the 1 B-B 6.9kV SDBD de-energized and the loads were shed, the alternate feeder breaker closed and re-energized the 1 B-B 6.9kV SDBD. The loads supplied by the 1 B-B 6.9kV SDBD were subsequently reconnected, and required tests were successfully completed to ensure operability of the 1 B-B 6.9kV SDBD. At the time of the event, WBN-1 was in MODE 5 following a refueling outage. Operations personnel promptly entered the appropriate response procedure and re-established power to required loads. The required safety systems functioned as designed. The licensee determined that the likely cause of this event was that plant operators did not ensure the alternate feeder breaker hand-switch was held firmly in the "closed" position while initiating the fast board transfer.
The inspectors reviewed the event and licensee corrective actions taken and no findings were identified. No findings or violations of NRC requirements were identified.
4OA6 Exit
Exit Meeting Summary
On February 22, 2013, the inspectors presented the inspection results to Mr. Tim Cleary, Acting Site-VP, and other members of licensee management. The inspectors confirmed that proprietary information was not provided or examined during the inspection.
ATTACHMENT:
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee personnel
- D. Gronek, Plant Manager
- H. Cusick, Employee Concerns Program Manager
- T. Morgan, Site Licensing
- S. Rymer, Site Engineering
- D. Guinn, Manager, Site Licensing
- R. Stroud, Site Licensing
- J. Hough, Site Licensing
- K. Dutton, Director Engineering
- S. Ferrell, CAP Analyst
- D. Hutchinson, Performance Improvement
- J. Deal, Manager, Quality Assurance
NRC personnel
- R. Monk, Senior Resident Inspector
LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED
Opened
None
Closed
- 05000390/2012-005 LER Automatic Start of Emergency Diesel Generators due to Failed Transfer of Power to 6.9kV Shutdown Board (Section 4OA2.3)
Opened and Closed
- 05000390/2013007-01 FIN Failure to Follow Procedure BP-529 Oversight of Supplemental Personnel