IR 05000528/2017007
| ML17096A762 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 04/06/2017 |
| From: | Thomas Farnholtz Region 4 Engineering Branch 1 |
| To: | Bement R Arizona Public Service Co |
| References | |
| IR 2017007 | |
| Download: ML17096A762 (18) | |
Text
pril 6, 2017
SUBJECT:
PALO VERDE NUCLEAR GENERATING STATION, UNITS 1, 2, AND 3 -
NRC EVALUATIONS OF CHANGES, TESTS, AND EXPERIMENTS BASELINE INSPECTION REPORT 05000528/2017007; 05000529/2017007; AND 05000530/2017007
Dear Mr. Bement:
On March 3, 2017, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your Palo Verde Nuclear Generating Station, Units 1, 2, and 3 and discussed the results of this inspection with Mr. J. Cadogan, Senior Vice President of Nuclear Operations, and other members of your staff. Inspectors documented the results of this inspection in the enclosed inspection report.
NRC inspectors documented one finding of very low safety significance (Green) in this report.
This finding involved a violation of NRC requirements. The NRC is treating this violation as a non-cited violation (NCV) consistent with Section 2.3.2.a of the Enforcement Policy.
If you contest the violation or significance of the NCV, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington DC 20555-0001; with copies to the Regional Administrator, Region IV; the Director, Office of Enforcement, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001; and the NRC resident inspector at the Palo Verde Nuclear Generating Station.
In accordance with Title 10 of the Code of Federal Regulations 2.390, Public Inspections, Exemptions, Requests for Withholding, of the NRC's "Rules of Practice," a copy of this letter, its enclosure, and your response (if any) will be available electronically for public inspection in the NRCs Public Document Room or from the Publicly Available Records (PARS) component of the NRC's Agencywide Documents Access and Management 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/
Thomas R. Farnholtz, Chief Engineering Branch 1 Division of Reactor Safety Docket Nos. 50-528, 50-529, 50-530 License Nos. NPF-41, NPF-51, NPF-74
Enclosure:
Inspection Report 05000528/2017007 05000529/2017007, and 05000530/2017007 w/Attachment: Supplemental Information
REGION IV==
Docket: 05000528, 05000529; 05000530 License: NPF-41, NPF-51, NPF-74 Report: 05000528/2017007; 05000529/2017007; and 05000530/2017007 Licensee: Arizona Public Service Company Facility: Palo Verde Nuclear Generating Station, Units 1, 2, and 3 Location: 5801 South Wintersburg Road Tonopah, AZ 85354 Dates: February 27 through March 3, 2017 Inspectors: J. Drake, Senior Reactor Inspector Lead J. Watkins, Reactor Inspector C. Smith, Reactor Inspector W. Cullum, Reactor Inspector Approved By: Thomas R. Farnholtz Chief, Engineering Branch 1 Division of Reactor Safety Enclosure
SUMMARY
IR 05000528/2017007, 05000529/2017007, and 05000530/2017007; Palo Verde Nuclear
Generating Station, Units 1, 2, and 3; Evaluations of Changes, Tests, and Experiments.
This report covers a one-week announced baseline inspection on evaluations of changes, tests, and experiments. The inspection was conducted by Region IV based engineering inspectors.
One finding was identified by the inspectors. The finding was considered a non-cited violation of NRC regulations. The significance of most findings is indicated by their color (i.e., greater than Green, or Green, White, Yellow, Red) using Inspection Manual Chapter 0609, Significance Determination Process (SDP). Cross-cutting aspects were determined using Inspection Manual Chapter 0310, Aspects Within the Cross-Cutting Areas. Violations of NRC requirements are dispositioned in accordance with the NRCs Enforcement Policy, dated July 9, 2013. The NRCs program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, Reactor Oversight Process, Revision 5, dated February 2014.
NRC-Identified Findings
and Self-Revealed Findings
Cornerstone: Mitigating Systems
- Green.
The team identified a Green non-cited violation of 10 CFR Part 50, Appendix B,
Criterion III, Design Control, which states, in part, Measures shall be established to assure that applicable regulatory requirements and the design basis, as defined in
§ 50.2 and as specified in the license application, for those structures, systems, and components to which this appendix applies are correctly translated into specifications, drawings, procedures, and instructions. Specifically, from August 11, 1982, to March 3, 2017, the licensee did not analyze dynamic pipe whip effects of a main feedwater line for a high-energy line break of a shutdown cooling line. In response to this issue, the licensee performed immediate and prompt operability evaluations and determined that the piping systems remained operable and could withstand the effects of a high-energy line break. This finding was entered into the licensees corrective action program as Condition Report CR-17-02815.
The team determined that the failure to perform an adequate analysis for shutdown cooling and feedwater lines for high-energy line break pipe whip effects was a performance deficiency. This finding was more-than-minor because it was associated with the design control attribute of the Mitigating Systems cornerstone and adversely affected the cornerstone objective of ensuring the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences.
Specifically, the failure to analyze the main feedwater piping for high-energy line break effects called the operability of the piping system into question. In accordance with Inspection Manual Chapter 0609, Appendix A, The Significance Determination Process (SDP) for Findings At-Power, dated June 19, 2012, Exhibit 2, Mitigating Systems Screening Questions, the issue screened as having very low safety significance (Green)because it was a design or qualification deficiency that did not represent a loss of operability or functionality; did not represent an actual loss of safety function of the system or train; did not result in the loss of one or more trains of non-technical specification equipment; and did not screen as potentially risk significant due to seismic, flooding, or severe weather. The team determined that this finding did not have a cross-cutting aspect because the most significant contributor to the performance deficiency did not reflect current licensee performance. Specifically, the licensee performed the calculation in 1982 and revised it in 1991; therefore, the performance deficiency occurred outside of the nominal three-year period for present performance.
(Section 4OA2.1)
Licensee-Identified Violations
No findings of more-than-minor significance were identified.
REPORT DETAILS
REACTOR SAFETY
Cornerstones: Initiating Events, Mitigating Systems, Barrier Integrity, and Emergency Preparedness
1R17 Evaluations of Changes, Tests, and Experiments
.1 Evaluations of Changes, Tests, and Experiments
a. Inspection Scope
The inspectors reviewed 13 evaluations performed pursuant to Title 10, Code of Federal Regulations (CFR), Part 50, Section 59, to determine whether the evaluations were adequate and that prior NRC approval was obtained as appropriate. The inspectors also reviewed 21 screenings, where licensee personnel had determined that a 10 CFR 50.59 evaluation was not necessary. The inspectors reviewed these documents to determine if:
- the changes, tests, and experiments performed were evaluated in accordance with 10 CFR 50.59 and that sufficient documentation existed to confirm that a license amendment was not required;
- the safety issue requiring the change, tests, and experiment was resolved;
- the licensee conclusions for evaluations of changes, tests, and experiments were correct and consistent with 10 CFR 50.59; and
- the design and licensing basis documentation was updated to reflect the change.
The inspectors used, in part, Nuclear Energy Institute (NEI) 96-07, Guidelines for 10 CFR 50.59 Implementation, Revision 1, to determine acceptability of the completed evaluations and screenings. The NEI document was endorsed by the NRC in Regulatory Guide 1.187, Guidance for Implementation of 10 CFR 50.59, Changes, Tests, and Experiments, dated November 2000. The list of evaluations, screenings, and/or applicability determinations reviewed by the inspectors is included as an attachment to this report.
This inspection constituted 13 samples of evaluations and 21 samples of screenings as defined in IP 71111.17-04.
b. Findings
No findings were identified.
OTHER ACTIVITIES
4OA2 Problem Identification and Resolution
.1 Review of Corrective Action Program Documents
a. Inspection Scope
The inspectors reviewed 10 corrective action program documents that identified or were related to the 10 CFR 50.59 program. The inspectors reviewed these documents to evaluate the effectiveness of corrective actions related to permanent plant modifications and evaluations of changes, tests, and experiments. In addition, corrective action documents written on issues identified during the inspection were reviewed to verify adequate problem identification and incorporation of the problems into the corrective action system. The list of specific corrective action documents that were sampled and reviewed by the inspectors are listed in the attachment to this report.
b. Findings
Failure to analyze shutdown cooling and feedwater lines for high-energy line break pipe whip effects
Introduction.
The team identified a Green non-cited violation of Title 10 of the Code of Federal Regulations Part 50, Appendix B, Criterion III, Design Control, for the licensees failure to translate regulatory requirements and the design basis into specifications, drawings, procedures, and instructions. Specifically, the licensee failed to analyze the dynamic pipe whip effects between the main feedwater and shutdown cooling lines.
Description.
The licensees updated final safety analysis report (UFSAR) states that the design basis for high-energy line breaks complies with Branch Technical Position (BTP) 3-1. Specifically, UFSAR, Section 3.6.2.1.3.C, states, in part, a whipping pipe is considered insufficient to rupture an impacted pipe of equal or larger nominal pipe size and equal or heavier wall thickness. BTP 3-1 states, in part, that protection from pipe whip is not required if the internal energy level associated with the whipping pipe can be demonstrated to be insufficient to impair the safety function of any SSC to an unacceptable level.the energy level in a whipping pipe may be considered insufficient to rupture an impacted pipe of equal or larger nominal pipe size and equal or heavier wall thickness.
Calculation 13-MC-ZZ-0633 analyzes high-energy line breaks for various piping systems.Section I analyzes the effects of a high-energy line break in the 16 inch, schedule 160, stainless steel shutdown cooling line on the 24 inch, schedule 80, carbon steel main feedwater line.Section I concludes that whipping pipe protection is not needed because the main feedwater line will not be damaged or impaired by the failure of the shutdown cooling line.
The impacted main feedwater line has a larger diameter than the shutdown cooling line; however, the main feedwater line is thinner (i.e., not equal or heavier wall thickness)than the shutdown cooling line; therefore, the design method used to exclude pipe whip protection for the main feedwater line is not in accordance with the design and licensing basis.
Analysis.
The team determined that the failure to perform an adequate analysis for shutdown cooling and feedwater lines for high-energy line break pipe whip effects was a performance deficiency. This finding was more-than-minor because it was associated with the design control attribute of the Mitigating Systems cornerstone and adversely affected the cornerstone objective of ensuring the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences.
Specifically, the failure to analyze the main feedwater piping for high-energy line break effects called the operability of the piping system into question. In accordance with Inspection Manual Chapter 0609, Appendix A, The Significance Determination Process (SDP) for Findings At-Power, dated June 19, 2012, Exhibit 2, Mitigating Systems Screening Questions, the issue screened as having very low safety significance (Green)because it was a design or qualification deficiency that did not represent a loss of operability or functionality; did not represent an actual loss of safety function of the system or train; did not result in the loss of one or more trains of non-technical specification equipment; and did not screen as potentially risk significant due to seismic, flooding, or severe weather. The team determined that this finding did not have a cross-cutting aspect because the most significant contributor to the performance deficiency did not reflect current licensee performance. Specifically, the licensee performed the calculation in 1982 and revised it in 1991; therefore, the performance deficiency occurred outside of the nominal three-year period for present performance.
Enforcement.
The team identified a Green non-cited violation of 10 CFR Part 50, Appendix B, Criterion III, Design Control, which states, in part, Measures shall be established to assure that applicable regulatory requirements and the design basis, as defined in § 50.2 and as specified in the license application, 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 August 11, 1982, to March 3, 2017, the licensee did not establish measures to assure that applicable regulatory requirements and the design basis for a system, structure, and component to which this appendix applies are correctly translated into specifications, drawings, procedures, and instructions. Specifically, the licensee did not analyze dynamic pipe whip effects of a main feedwater line for a high-energy line break of a shutdown cooling line. In response to this issue, the licensee performed immediate and prompt operability evaluations and determined that the piping systems remained operable and could withstand the effects of a high-energy line break. This finding was entered into the licensees corrective action program as Condition Report CR-17-02815. Because this finding was of very low safety significance and was entered into the licensees corrective action program, this violation is being treated as a non-cited violation, consistent with Section 2.3.2.a of the NRC Enforcement Policy:
NCV 05000528/2017007-01; 05000529/2017007-01; 05000530/2017007-01:
Failure to Analyze Shutdown Cooling and Feedwater Lines for High-Energy Line Break Pipe Whip Effects.
4OA6 Meetings
Exit Meeting Summary
On March 3, 2017, the inspectors presented the preliminary inspection results to Mr. J. Cadogan, Senior Vice President of Nuclear Operations, and other members of the licensees staff. The licensee acknowledged the results as presented. While some proprietary information was reviewed during this inspection, no proprietary information was included in this report.
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee Personnel
- J. Cadogan, Senior Vice President of Nuclear Operations
- M. Lacal, Senior Vice President of Regulatory and Oversight
- B. Rash, Vice President, Engineering
- R. Carbonneau, Director, Nuclear Assurance
- B. Berles, Director, Nuclear Fuel Management
- G. Andrews, Director, Regulatory Affairs
- P. Paramithar, Director, Project Engineering
- M. McGhee, Department Leader, Nuclear Regulatory Affairs
- M. Radspinner, Department Leader, System Engineering
- D. Elkinton, Section Leader, Compliance
- P. Han, Senior Engineer
- R. Chu, Engineer
- N. Aaroncooke, Engineer
- R. Doyle, Engineer
NRC Personnel
- C. Peabody, Senior Resident Inspector
- D. Reinert, Resident Inspector
- D. You, Resident Inspector
LIST OF ITEMS OPENED, CLOSED, DISCUSSED, AND UPDATED
Opened and Closed
- 05000528/2017007-01 NCV Failure to Analyze Shutdown Cooling and Feedwater Lines for High-Energy Line Break Pipe Whip Effects (Section 4OA2)
- 05000529/2017007-01 NCV Failure to Analyze Shutdown Cooling and Feedwater Lines for High-Energy Line Break Pipe Whip Effects (Section 4OA2)
- 05000530/2017007-01 NCV Failure to Analyze Shutdown Cooling and Feedwater Lines for High-Energy Line Break Pipe Whip Effects (Section 4OA2)