IR 05000483/2014008

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IR 05000483/2014008; on 08/11/2014 - 09/23/2014; Callaway Plant; Problem Identification and Resolution (Biennial)
ML14311A026
Person / Time
Site: Callaway Ameren icon.png
Issue date: 11/06/2014
From: Geoffrey Miller
Division of Reactor Safety IV
To: Diya F
Union Electric Co
Miller G
References
IR 2014008
Download: ML14311A026 (26)
v • d • e


Text

November 6, 2014

SUBJECT:

CALLAWAY PLANT - NRC PROBLEM IDENTIFICATION AND RESOLUTION INSPECTION REPORT 05000483/2014008

Dear Mr. Diya:

On August 29, 2014, the U.S. Nuclear Regulatory Commission (NRC) completed the onsite portion of a biennial problem identification and resolution inspection at the Callaway Plant and provided you and your staff with a debrief of the preliminary findings. On September 23, 2014, NRC inspection team discussed the results of this inspection telephonically with Mr. Scott Maglio, Regulatory Affairs Manager, and other members of your staff. The inspection team documented the results of this inspection in the enclosed inspection report.

Based on the inspection sample, the inspection team determined that Callaway Plants corrective action program, and your staffs implementation of the corrective action program, were adequate to support nuclear safety.

In reviewing your corrective action program, the team assessed how well your staff identified problems at a low threshold, your staffs implementation of the stations process for prioritizing and evaluating these problems, and the effectiveness of corrective actions taken by the station to resolve these problems. The team also evaluated other processes your staff used to identify issues for resolution. These included your use of audits and self-assessments to identify latent problems and your incorporation of lessons learned from industry operating experience into station programs, processes, and procedures. The team determined that your stations performance in each of these areas supported nuclear safety.

Finally, the team determined that your stations management maintains a safety-conscious work environment in which your employees are willing to raise nuclear safety concerns through at least one of the several means available.

NRC inspectors documented two findings of very low safety significance (Green) in this report.

These findings involved violations of NRC requirements. The NRC is treating these violations as non-cited violations (NCVs) consistent with Section 2.3.2.a of the NRC Enforcement Policy.

UNITED STATES NUCLEAR REGULATORY COMMISSION

REGION IV

1600 E LAMAR BLVD ARLINGTON, TX 76011-4511 If you contest the violations or significance of these NCVs, 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 Callaway Plant.

If you disagree with a cross-cutting aspect assignment 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, Region IV; and the NRC resident inspector at the Callaway Plant.

In accordance with Title 10 of the Code of Federal Regulations (10 CFR) 2.390, Public Inspections, Exemptions, Requests for Withholding, 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/

Geoffrey B. Miller, Chief Technical Support Branch Division of Reactor Safety

Docket: 50-483 License: NPF-30

Enclosure:

Inspection Report 05000483/2014008 w/Attachment: Supplemental Information

REGION IV==

Docket:

05000483 License:

NPF-30 Report:

05000483/2014008 Licensee:

Union Electric Company Facility:

Callaway Plant Location:

Junction of Highway CC and Highway O Steedman, MO Dates:

August 11 through September 23, 2014 Team Lead:

Harry Freeman, Senior Reactor Inspector Inspectors:

Thomas Hartman, Senior Resident Inspector Abin Fairbanks, Resident Inspector Christopher Henderson, Resident Inspector Approved By:

Geoffrey B. Miller, Chief Technical Support Branch Division of Reactor Safety

- 2 -

SUMMARY

IR 05000483/2014008; 08/11/2014 - 09/23/2014; Callaway Plant; Problem Identification and

Resolution (Biennial)

The team performed the activities described in this report between August 11 and August 29, 2014. The team consisted of a senior reactor inspector from the NRCs Region IV office, the senior resident inspector at Callaway Plant, a resident inspector from Arkansas Nuclear One, and a resident inspector from Cooper Nuclear Station. The report documents two findings of very low safety significance (Green) which involved violations of NRC requirements. The significance of inspection findings is indicated by their color (i.e., Greater than Green, or Green,

White, Yellow, Red), and determined using Inspection Manual Chapter 0609, Significance Determination Process. Their cross-cutting aspects are determined using Inspection Manual Chapter 0310, Aspects Within the Cross-Cutting Areas. All violations of NRC requirements are dispositioned in accordance with the NRC Enforcement Policy. The NRC's program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, Reactor Oversight Process.

Assessment of Problem Identification and Resolution

Based on its inspection sample, the team concluded that the licensee maintained a corrective action program in which individuals identified issues at an appropriately low threshold. Once entered into the corrective action program, the licensee generally evaluated and addressed these issues appropriately and timely, commensurate with their safety significance. The licensees corrective actions were generally effective, addressing the causes and extents of condition of problems.

The licensee appropriately evaluated industry-operating experience for relevance to the facility and entered applicable items in the corrective action program. The licensee incorporated industry and internal operating experience in its root cause and apparent cause evaluations.

The licensee performed effective and self-critical nuclear oversight audits and self-assessments.

The licensee maintained an effective process to ensure significant findings from these audits and self-assessments were addressed.

The licensee maintained a safety-conscious work environment in which personnel were willing to raise nuclear safety concerns without fear of retaliation.

Cornerstone: Mitigating Systems

Green.

The team identified a non-cited violation of 10 CFR Part 50, Appendix B, Criterion V,

Instructions, Procedures, and Drawings, associated with the licensees failure to assess operability in accordance with Station Procedure APA-ZZ-00500 Appendix 1, Operability and Functionality Determinations, Revision 22. Specifically, the licensee failed to assess operability when taking safety-related electrical cabinets and switchgear out of their seismically qualified configuration during maintenance activities. The licensee entered this deficiency into their corrective action program for resolution as Callaway Action Request 201405359.

The licensees failure to assess the basis for operability of a degraded or nonconforming condition was a performance deficiency. This performance deficiency was more than minor because it was associated with the equipment performance attribute of the Mitigating

Systems cornerstone and affected the associated objectives to ensure availability, reliability, and capability of systems that responds to initiating events to prevent undesirable consequences. Specifically, the licensees failure to assess and document operability resulted in conditions of unknown operability for degraded or nonconforming conditions.

The finding is of very low safety significance (Green) because although it affected the qualification of one or more mitigating systems, structures or components (SSCs), these SSCs maintained their functionality. The finding has a cross-cutting aspect in the area of human performance associated with how the organization implements a process of planning, controlling, and executing work activities such that nuclear safety is the overriding priority. In this case, the licensees work control process failed to evaluate the activity in order to assure nuclear safety [H.5]. (Section 4OA2.5a)

Green.

The team identified a non-cited violation of 10 CFR Part 50, Appendix B,

Criterion III, Design Control, associated with the licensees failure to verify the adequacy of the design of the turbine-driven auxiliary feedwater pump exhaust stack to be able to withstand the effects of natural phenomena. Specifically, the licensee failed to verify that the exhaust stack of the turbine was protected from the effects of tornado-generated missiles. The licensee entered this deficiency into their corrective action program for resolution as Callaway Action Request 201405508.

The licensees failure to verify the adequacy of the design was a performance deficiency.

This performance deficiency was more than minor because it was associated with protection against external events attribute of the mitigating systems cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, the licensee failed to ensure the reliability of the turbine-driven auxiliary feedwater pump after a postulated tornado missile impact to the steam exhaust piping. The finding was of very low safety significance because it represented a qualification deficiency that did not result in the loss of operability or functionality. The finding had a cross-cutting aspect in the area of problem identification and resolution for the licensees failure to thoroughly evaluate issues to ensure that resolutions address causes and extent of conditions commensurate with their safety significance [P.2]. (Section 4OA2.5.b)

REPORT DETAILS

OTHER ACTIVITIES (OA)

4OA2 Problem Identification and Resolution

Main article: IP 71152

The team based the following conclusions on a sample of corrective action documents that were open during the assessment period, which ranged from July 14, 2012, to the end of the on-site portion of this inspection on August 29, 2014.

.1 Assessment of the Corrective Action Program Effectiveness

a. Inspection Scope

The team reviewed approximately 200 condition reports also known as Callaway Action Requests (CARs), including associated root cause analyses and apparent cause evaluations, from approximately 14,000 that the licensee had initiated or closed during the assessment period. The majority of these (approximately 13,600) were lower-level conditions that did not require cause evaluations. The inspection sample focused on higher-significance conditions for which the licensee evaluated and took actions to address the cause of the condition. In performing its review, the team evaluated whether the licensee had properly identified, characterized, and entered issues into the corrective action program, and whether the licensee had appropriately evaluated and resolved the issues in accordance with established programs, processes, and procedures. The team also reviewed these programs, processes, and procedures to determine if any issues existed that may impair their effectiveness.

The team reviewed a sample of performance metrics, system health reports, operability determinations, self-assessments, trending reports and metrics, and various other documents related to the licensees corrective action program. The team evaluated the licensees efforts in determining the scope of problems by reviewing selected logs, work orders, self-assessment results, audits, system health reports, action plans, and results from surveillance tests and preventive maintenance tasks. The team reviewed daily CARs and attended the licensees screening and corrective action review board meetings to assess the reporting threshold and prioritization efforts, and to observe the corrective action programs interfaces with the operability assessment and work control processes. The teams review included an evaluation of whether the licensee considered the full extent of cause and extent of condition for problems, as well as a review of how the licensee assessed generic implications and previous occurrences of issues. The team assessed the timeliness and effectiveness of corrective actions, completed or planned, and looked for additional examples of problems similar to those the licensee had previously addressed. The team conducted interviews with plant personnel to identify other processes that may exist where problems may be identified and addressed outside the corrective action program.

The team reviewed corrective action documents that addressed past NRC-identified violations to evaluate whether corrective actions addressed the issues described in the inspection reports. The team reviewed a sample of corrective actions closed to other corrective action documents to ensure that the ultimate corrective actions remained appropriate and timely.

The team considered risk insights from both the NRCs and Callaways risk models to focus the sample selection and plant tours on risk-significant systems and components.

The team focused a portion of its sample on the component cooling water, the auxiliary feedwater, and the 4160-volt electrical distribution systems, which the team selected for a five-year in-depth review. The team conducted walk-downs of these systems and other plant areas to assess whether licensee personnel identified problems at a low threshold and entered them into the corrective action program.

b. Assessments

1. Effectiveness of Problem Identification

During the 24-month assessment period, licensee staff generated approximately 14,000 CARs. The team determined that most conditions that required generation of a condition report (per procedure APA-ZZ-00500 Corrective Action Program) had been appropriately entered into the corrective action program.

Overall, the team concluded that the licensee generally identified issues and adverse conditions in accordance with its corrective action program and NRC requirements.

The team determined that the licensee generally maintained a low threshold for the formal identification of problems and entry into the corrective action program for evaluation. Licensee personnel initiated on average 580 CARs per month during the assessment period. All personnel interviewed by the team understood the requirements for condition report initiation and expressed a willingness to enter newly identified issues into the corrective action program at a very low threshold.

2. Effectiveness of Prioritization and Evaluation of Issues

The sample of CARs reviewed by the team focused primarily on issues screened by the licensee as having higher-level significance, including those that received cause evaluations, those classified as significant conditions adverse to quality, and those that required engineering evaluations. The team also reviewed a number of Callaway Action Requests that included or should have included immediate operability determinations to assess the quality, timeliness, and prioritization of these determinations.

Overall, the team determined that the licensees process for screening and prioritizing issues that had been entered into the corrective action program supported nuclear safety. The licensees operability determinations were consistent, accurately documented, and completed in accordance with procedures.

Once the licensee enters issues into the corrective action program, they were generally screened to the appropriate level as required by APA-ZZ-00500, Corrective Action Program, and associated attachments. However, the team noted some issues with the completeness of evaluations on adverse conditions that may warrant management attention. These issues include:

  • The licensee failed to account for the temperature difference between the inside and the outside of electrical cabinets in the Class 1E electrical rooms, as well as the effects of these increased temperatures in their room heat-up calculations. This calculation had been performed to support operability of safety-related electrical equipment with a single control building chiller out-of-service, and had been used to support past operability evaluations. This failure to adequately analyze maximum electrical equipment temperatures resulting from the single failure of control building heating ventilation/air conditioning was previously documented as a non-cited violation in NRC Inspection Report 05000483/2014007.

In April 2014, the licensee changed their corrective action program to align with recommendations in an industry initiative titled, Industry Cumulative Impact Summary Report dated October 16, 2013. The biggest change to the program involved a few new classifications of issues. The first was called Condition Adverse to Quality Plus (CAQ+). These were issues that may impact the safety of the station but not affect Technical Specification equipment. The licensee also added a classification called Other Issues. These were issues that do not rise to the level of CAQ+ such as enhancements to procedures, painting needs, housekeeping, etc.

Previously all low-level issues were classified as conditions adverse to quality so the licensee had to re-characterize those issues and reclassify them as other issues.

This initiative has helped the licensee prioritize the items that may have a more significant impact to the plant. Through their review of this initiative, the licensee has recognized that low level conditions adverse to quality were not being self-identified at as high a rate as originally thought. The licensee was reviewing this matter to determine whether further actions were warranted.

Overall, the team determined that the licensee had a strong process for screening and prioritizing issues that were entered into the corrective action program. All departments were represented at CAR screening meetings. The departments took clear ownership of the issues discussed and set appropriate due dates for evaluation of the issues identified in the CARs, in accordance with APA-ZZ-00500, Corrective Action Program, and associated attachments.

3. Effectiveness of Corrective Actions

Overall, the team concluded that the licensee generally identified effective corrective actions for the problems evaluated in the corrective action program. The licensee generally implemented these corrective actions in a timely manner, commensurate with their safety significance, and reviewed the effectiveness of the corrective actions appropriately.

While the team noted some issues with the timeliness of corrective actions, they were generally completed by their due dates and due date extensions were generally reasonable and were not overused. When appropriate corrective actions were implemented, they were generally effective. However, the team identified some examples of corrective actions not addressing the actual cause of the issue.

  • After a failure of essential service water pump room supply fan dampers in July 2011, the licensee incorrectly evaluated the condition. The licensees evaluation presumed, based on industry operating experience that a circuit card had failed. The licensee replaced the circuit card and returned the dampers to service. However, the failure was the result of pinched wires; the circuit card was fully functional. The failure recurred in August 2011. This issue was previously documented as a non-cited violation for failure to identify and correct a condition adverse to quality in NRC Inspection Report 05000483/2012008.
  • The class 1E electrical air conditioning units had sixteen refrigerant leaks over a four-year period. Each time the licensee replaced the tubing and returned the system to service. The licensee failed to address the cause of the leaks.

The leaks were due to fretting caused by inadequate support of some instrument tubing. This issue was previously documented as a non-cited violation for failure to correctly screen repetitive equipment failures in NRC Inspection Report 05000483/2013003.

The team noted that corrective actions to address the sample of NRC non-cited violations and findings since the last problem identification and resolution inspection had been timely and effective.

Overall, the team concluded that the licensee generally developed appropriate corrective actions to address identified problems. The licensee generally implemented these corrective actions in a timely manner, commensurate with their safety significance. The licensee generally has performed timely effectiveness reviews of significant corrective actions to verify their adequacy.

.2 Assessment of the Use of Operating Experience

a. Inspection Scope

The team examined the licensees program for reviewing industry operating experience, including reviewing the governing procedures. The team reviewed a sample of 20 industry operating experience communications and the associated site evaluations to assess whether the licensee had appropriately assessed the communications for relevance to the facility. The team also reviewed assigned actions to determine whether they were appropriate.

b. Assessment

Overall, the team determined that the licensee appropriately evaluated industry operating experience for its relevance to the facility. Operating experience information was incorporated into plant procedures and processes as appropriate. However, the team noted two examples during the assessment period where the licensee failed to adequately address operating experience:

  • The licensee failed to thoroughly evaluate operating experience related to a White finding for failure to analyze the effects of a tornado-born missile impact on the turbine-driven auxiliary feedwater exhaust piping and failed to identify a similar condition at Callaway Plant. (Section 4OA2.5b)
  • The licensee failed to adequately monitor the cooling water flow through the safety-related room coolers to ensure they maintained their capability to remove the heat from the rooms. This finding had a cross-cutting aspect in the area of problem identification and resolution associated with the operating experience because the cause of this finding involved the failure to systematically collect, evaluate, and communicate relevant internal operating experience related to silting. This issue was previously dispositioned as a non-cited violation for failure to adequately monitor the performance or condition of structures, systems, or components within the scope of the maintenance rule in NRC Inspection Report 05000483/2013003.

The team further determined that the licensee appropriately evaluated industry-operating experience when performing root cause analysis and apparent cause evaluations. The licensee appropriately incorporated both internal and external operating experience into lessons learned for training and pre-job briefs.

.3 Assessment of Self-Assessments and Audits

a. Inspection Scope

The team reviewed a sample of licensee self-assessments and audits to assess whether the licensee was regularly identifying performance trends and effectively addressing them. The team also reviewed audit reports to assess the effectiveness of assessments in specific areas. The specific self-assessment documents and audits reviewed are listed in Attachment 1.

b. Assessment

Overall, the team concluded that the licensee had an effective self-assessment and audit process. The team determined that self-assessments were self-critical and thorough enough to identify deficiencies. However, the team noted one example documented during the assessment period where the lack of timely action led to component failure and a subsequent reactor transient.

  • In 2005, the licensee initiated a request for resolution and a health issue to document and address the fact that the installed backdraft dampers on the isophase coolers were not rated for system airflow. During a 2011 inspection, the licensee noted that a damper blade had failed and was found in the B phase of the isophase bus duct.

The CAR was generated but given a low significance. A new health issue for a single point vulnerability was not generated. On July 26, 2013, a subsequent failure caused a damper blade to enter the isophase bus duct and resulted in a main turbine and reactor trip. The licensees failure to correct a design deficiency in main generator bus duct cooling system was previously documented as a finding in NRC Inspection Report 05000483/2014002.

.4 Assessment of Safety-Conscious Work Environment

a. Inspection Scope

The team interviewed 33 individuals in four focus groups. The team also conducted individual interviews with staff members during the inspection. The purpose of these interviews was

(1) to evaluate the willingness of licensee staff to raise nuclear safety issues, either by initiating a condition report or by another method,
(2) to evaluate the perceived effectiveness of the corrective action program at resolving identified problems, and
(3) to evaluate the licensees safety-conscious work environment. The focus group participants included personnel from security, operations, instrumentation and controls, and health physics. With the licensees regulatory affairs staff, the team randomly selected the participants from these work groups, based partially on availability. The team reviewed the Employee Concerns Program case log and select case files. The team also reviewed the minutes from the licensees most recent safety culture monitoring panel meetings.

b. Assessment

1. Willingness to Raise Nuclear Safety Issues

All individuals interviewed indicated that they would raise nuclear safety concerns.

All felt that their management was receptive to nuclear safety concerns and was willing to address them promptly. All of the interviewees further stated that if they were not satisfied with the response from their immediate supervisor, they had the ability to escalate the concern to a higher organizational level. Most expressed positive experiences after raising issues to their supervisors. All expressed positive experiences documenting most issues in CARs.

2. Employee Concerns Program

All interviewees were aware of the Employee Concerns Program. Most explained that they had heard about the program through various means, such as posters, training, presentations, and discussion by supervisors or management at meetings.

All interviewees stated that they would use Employee Concerns if they felt it was necessary. All expressed confidence that their confidentiality would be maintained if they brought issues to Employee Concerns.

3. Preventing or Mitigating Perceptions of Retaliation

When asked if there have been any instances where individuals experienced retaliation or other negative reaction for raising issues, all individuals interviewed stated that they had neither experienced nor heard of an instance of retaliation, harassment, intimidation, or discrimination at the site. The team determined that processes in place to mitigate these issues were being successfully implemented.

4. Changes to Corrective Action Program in Response to Cumulative Impact Initiative

When asked for comments regarding the licensees implementation of changes to the corrective action program in response to the Industry Cumulative Impact Summary Report dated October 16, 2013, (Section 4OA2.1b2 above), almost without exception, the employees responded favorably noting that the changes should help remove trivial issues (those that had no impact or bearing on safety)from the program and should help focus attention on important issues. The few exceptions to this response were based upon a concern that those issues that should receive management attention and corrective actions that were now being categorized as a condition adverse to quality plus (CAQ+) or other issues would no longer be addressed. These comments were not based upon any actual failures by the licensee to address or correct conditions adverse to quality.

.5 Findings

a. Failure to Assess Operability of Safety-Related Equipment when placing Seismically Qualified Electrical Cabinets in a Non-Qualified Condition with their Doors Open

Introduction.

The team identified a Green non-cited violation of 10 CFR Part 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, associated with the licensees failure to assess operability in accordance with Station Procedure APA-ZZ-00500 Appendix 1, Operability and Functionality Determinations, Revision 22. Specifically, the licensee failed to assess operability when taking safety-related electrical cabinets and switchgear out of their seismically qualified configuration during maintenance activities.

Description.

The team conducted a walk down of the safety-related Division I, 4160 Vac switchgear, NB01, and reviewed CAR 201307355. The team noted that the switchgear doors were opened during maintenance activities and asked the following questions:

(1) Are the safety-related 4160 Vac switchgears NB01 and NB02 and other safety-related electrical cabinets seismically qualified when the cabinet doors are open?
(2) If the safety-related electrical cabinets and switchgear are not seismically qualified with the doors open, how is operability assessed when safety-related electrical cabinet doors are opened during maintenance activities?

The licensee informed the team that the safety-related electrical cabinets and switchgear were only seismically qualified with the doors closed, therefore, when the doors are opened, the safety-related electrical cabinets were not seismically qualified.

Additionally, the station did not assess operability of safety-related electrical cabinets and switchgear for maintenance activities that required opening the doors during the work control process. The licensee entered this issue in the stations corrective action program as CAR 201405359.

Analysis.

The licensees failure to properly assess and document the basis for operability when a degraded or nonconforming condition was identified was a performance deficiency. This performance deficiency was more than minor, and therefore a finding, because it was associated with the equipment performance attribute of the Mitigating Systems cornerstone and affected the associated objectives to ensure availability, reliability, and capability of systems that responds to initiating events to prevent undesirable consequences. Specifically, the licensees failures to assess and document operability of safety-related equipment while in a degraded condition with cabinet doors open may have resulted in conditions when the equipment may not have been able to respond to initiating events. Using Inspection Manual Chapter 0609, Appendix A, The Significance Determination Process (SDP) for Findings At-Power, Exhibit 2, Mitigating Systems Screening Questions, dated July 1, 2012, the team determined that the finding is of very low safety significance (Green) because although it affected the qualification of one or more mitigating systems, structures or components (SSCs), these SSCs maintained their functionality. The finding has a cross-cutting aspect in the area of human performance associated with work management because the licensees process of planning, controlling, and executing work activities failed to identify and evaluate the risk to assure that nuclear safety was the overriding priority

[H.5].

Enforcement.

Title 10 CFR Part 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, requires that activities affecting quality be prescribed by documented instructions, procedures, or drawings, of a type appropriate to the circumstances, and that they be accomplished in accordance with these instructions procedures, or drawings. Station Procedure APA-ZZ-00500 Appendix 1, Operability and Functionality Determinations, Revision 22, for evaluating the operability of safety-related components, required the licensee to immediately complete an operability or functionality determination for issues involving potentially degraded or nonconforming conditions. The procedure stated in part that an unanalyzed condition should be thought of as a degraded or nonconforming condition. Contrary to the above, until identified by the team in August 2014 activities affecting quality were not accomplished in accordance with a procedure that was appropriate to the circumstances. Specifically, the licensee failed to assess operability when taking safety-related electrical cabinets and switchgear out of their seismically qualified configuration during maintenance activities. This violation is being treated as a non-cited violation, consistent with Section 2.3.2.a of the Enforcement Policy. The licensee entered the violation into the corrective action program as CAR 201405359. (NCV 05000483/2014008-01, Failure to Follow Operability Procedure)

b. Failure to analyze for the effects of a tornado missile strike on the turbine-driven auxiliary feedwater pump steam exhaust piping

Introduction.

The team identified a Green non-cited violation of 10 CFR Part 50, Appendix B, Criterion III, Design Control, for the licensees failure to analyze for the effects of a tornado missile strike on the turbine-driven auxiliary feedwater pump steam exhaust piping.

Description.

While performing a 5-year review of the auxiliary feedwater system, the team reviewed CAR 201402940 which evaluated industry operating experience related to a White finding involving failure to establish applicable tornado missile protection design requirements for components needed to ensure the capability to shut down the reactor and maintain it in a safe shutdown condition. The affected components included the steam turbine-driven auxiliary feedwater pump exhaust stack, auxiliary feedwater components, raw water pump electrical pull boxes, and diesel generator fuel oil storage tank fill and vent lines.

The licensees review of the operating experience focused on the other licensees incorrect conclusion that the components were operable based on the low probability of a tornado missile impact. The licensee concluded through a review of Callaway action requests that the finding was not applicable to Callaway because probability was not used at Callaway to justify operability of components after an assumed tornado missile strike. The team determined that the review was narrowly focused on the use of probability and did not confirm that tornado missile protection existed for similar components at Callaway. The team requested the licensees analysis demonstrating that the turbine-driven auxiliary feedwater pump steam exhaust piping would not be adversely impacted by a tornado missile impact. The licensee provided the team Request for Resolution 200606712, which addressed a previous question by NRC inspectors about the missile protection requirement of the turbine-driven auxiliary feedwater pump steam exhaust piping. The licensee concluded that because the turbine-driven auxiliary feedwater pump exhaust piping had several similarities to the diesel generator exhaust stacks, the exhaust piping did not require missile protection.

The team identified that the conclusion in Request for Resolution 200606712 was not correct, and the subject exhaust piping required tornado missile protection verification based on the licensees design basis. The team based this conclusion on Final Safety Analysis Report 10.4.9.1.1, Safety Design Basis One, which stated, the [auxiliary feedwater system] is protected from the effects of natural phenomena, such as earthquakes, tornadoes, hurricanes, floods, and external missiles (GDC-2).

The licensee documented the nonconforming condition in CAR 201405508 and performed an operability determination. The team reviewed the licensees operability determination and concluded the evaluation provided reasonable assurance that the function of the auxiliary feedwater system was maintained.

Analysis.

The licensees failure to analyze for the effects of a tornado missile strike on the turbine-driven auxiliary feedwater pump steam exhaust piping was a performance deficiency. The finding was more than minor because it was associated with the protection against external events attribute of the mitigating systems cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, the licensee failed to ensure the reliability of the turbine-driven auxiliary feedwater pump after a postulated tornado missile impact to the steam exhaust piping. Using Manual Chapter 0609, Attachment 4, Initial Characterization of Findings, dated June 19, 2012, and Appendix A, The Significance Determination Process (SDP) for Findings at Power, dated June 19, 2012, Exhibit 2, Mitigating Systems Screening Questions, the team determined that the finding was of very low safety significance (Green) because it was a qualification deficiency confirmed not to result in loss of operability or functionality. The finding had a cross-cutting aspect in the area of problem identification and resolution for the licensees failure to thoroughly evaluate issues to ensure that resolutions address causes and extent of conditions commensurate with their safety significance. Specifically, the licensees evaluation of industry operating experience was narrowly focused and failed to identify that the subject steam exhaust piping had not been demonstrated to be protected from tornado missile impacts (P.2).

Enforcement.

Title 10 CFR Part 50, Appendix B, Criterion III, Design Control, requires, in part, that design control measures be provided for verifying or checking the adequacy of design, such as by the performance of design reviews, by the use of alternate or simplified calculational methods, or by the performance of a suitable testing program.

Contrary to the above, the licensee failed to verify the adequacy of the design of the turbine-driven auxiliary feedwater pump exhaust stack to be able to withstand the effects of natural phenomena. Specifically, as of August 20, 2014, the licensee failed to verify that the exhaust stack of the turbine-driven auxiliary feedwater pump was protected from the effects of tornado generated missiles. The licensee performed an operability determination that concluded that the auxiliary feedwater system function would be maintained after a tornado missile impact to the exhaust piping. Because this violation was of very low safety significance and was entered into the licensees corrective action program as CAR 201405508, it is being treated as a non-cited violation, consistent with Section 2.3.2.a of the Enforcement Policy. (NCV 05000483/2014008-02, Failure to Analyze for Tornado Missile Strike on Turbine Driven Auxiliary Feedwater Steam Exhaust Piping)

c. Appropriateness of Using a 7-Day Mission Time in Emergency Diesel Generator Operability Evaluations

Introduction.

The team identified an unresolved item concerning the licensees operability evaluations associated with a 7-day mission time for the emergency diesel generators as written in Station Procedure APA-ZZ-00500 Appendix 1, Operability and Functionality Determinations, Revision 22, and the assumption in FSAR Section 3.1.2 crediting the loss of offsite power and restored in 7 days. The team noted that the design basis accidents in FSAR Chapter 15 were analyzed to 30 days and questioned whether operability determinations using an emergency diesel generator 7-day mission time was appropriate.

Description.

The team reviewed CARs 201303303 and 201303613 and Station Procedure APA-ZZ-00500 Appendix 1, Operability and Functionality Determinations, Revision 22, concerning jacket water leaks on emergency diesel generators A and B.

The team noted the station had used a 7-day mission time for the emergency diesel generators operability evaluations and declared both emergency diesel generators operable. Station Procedure APA-ZZ-00500 Appendix 1 stated in part that the emergency diesel generator mission time is 7 days [and that] this is consistent with the 7-day capacity of the emergency diesel generator fuel storage tanks.

The team noted that Technical Specification Basis 3.8.3, Diesel Fuel, Lube Oil, and Starting Air and FSAR Section 9.5.4, Emergency Diesel Engine Fuel Oil Storage and Transfer System do require a 7-day capacity for the emergency diesel generator fuel storage tanks. This requirement, in conjunction with the ability to obtain replacement of fuel supplies within 7 days, supports the availability of the emergency diesel generators required to shut down the reactor and to maintain it in a safe condition for an anticipated operational occurrence or a postulated design basis accident with a loss of offsite power.

The licensee stated the basis for the emergency diesel generator 7-day mission was contained in FSAR Section 3.1.2 Additional Single Failure Assumptions, and was part of the original FSAR submittal to the NRC, and not APA-ZZ-00500 Appendix 1.

FSAR Section 3.1.2 states, in part,

In designing for and analyzing for Design Basis Accidents (i.e., large break loss-of-coolant accident, main steam line break, main feedwater line break, rod rejection, locked reactor coolant pump rotor or shaft break, fuel handling accident, or steam generator tube rupture), the following assumptions (a-f) are made in addition to postulating the initiating event.

e. All offsite power is simultaneously lost and is restored within 7 days (except for the events postulated to occur during MODE 5, MODE 6, and/or during movement of irradiated fuel assemblies when the plant is MODE 5 or MODE 6 or with the core fully offloaded, such as a fuel handling accident, a loss of all offsite power is not required to be assumed in addition to a single failure.)

The team reviewed Safety Evaluation Report (SER) and FSAR Section 15.0 Accident Analysis to determine if the stations basis of restoring offsite power in 7 days was appropriate when evaluating operability of emergency diesel generators for degraded nonconforming conditions. The SER did not document whether the NRC approved or disapproved the assumption of restoration of offsite power in 7 days during a design basis accident (FSAR Section 15). However, the team noted the following contained in FSAR Section 15:

The basic principle applied in relating design requirements to each of the conditions is that the most probable occurrences should yield the least radiological risk to the public, and those extreme situations having the potential for the greatest risk to the public shall be those least likely to occur. Where applicable, reactor trip system and engineered safeguards functioning assumed to the extent allowed by considerations, such as the single failure criterion, in fulfilling this principle. This means that seismic Category I, Class IE (safety-related 4160 Vac Buses NB01 and NB02 and emergency diesel generators A and B), and IEEE qualified equipment, instrumentation, and components are used in the ultimate mitigation of the consequences of Conditions II (Faults of moderate frequency), III (Infrequent faults), and IV (Limiting faults-design basis accidents) events.

The team determined that more inspection was necessary to resolve whether it was appropriate to evaluate emergency diesel generator operability using a 7-day mission time based on the restoration of offsite power as stated in FSAR Section 3.1.2, when no discussion of restoring offsite power was contained in the SER and FSAR Section 15.

Since, further NRC clarification/interpretation of the existing guidance is necessary, the issue is considered an unresolved item pending further NRC review.

(URI 05000483/2014008-03, Emergency Diesel Generator Operability Evaluations using a 7-Day Mission Time)

4OA6 Meetings, Including Exit

Exit Meeting Summary

On August 29, 2014, the inspectors presented the inspection results to Mr. Fadi Diya, Senior Vice President and Chief Nuclear Officer, and other members of the licensee staff. The licensee acknowledged the issues presented. The team conducted a final exit meeting telephonically on September 23, 2014, with the regulatory affairs manager and other members of the licensee staff confirming that they would document the emergency diesel generator mission time issue as an unresolved item in this inspection report to be resolved in a future NRC inspection report.

The licensee confirmed that they had not provided any proprietary information for reviewed to the inspectors.

SUPPLEMENTAL INFORMATION

KEY POINTS OF CONTACT

Licensee Personnel

F. Diya, Senior Vice President and Chief Nuclear Officer
D. Neterer, Vice President Nuclear Operations
B. Cox, Senior Director, Nuclear Operations
L. Graessle, Senior Director, Operations Support
M. McLachlan, Senior Director, Engineering
S. Kovaleski, Director, Engineering Design
S. Abel, Director, Engineering Projects
G. Bradley, Director, Engineering Systems
T. Fugate, Director, Maintenance
J. Heyer, Director, Nuclear Oversight
T. Moser, Director, Nuclear Projects
L. Sandbothe, Director, Plant Support
R. Farnam, Director, Training
J. Small, Manager, Chemistry
M. Killebrew, Manager, Maintenance
M. Covey, Manager, Operations
S. McLaughlin, Manager, Performance Improvement
C. Smith, Manager, Radiation Protection
S. Maglio, Manager, Regulatory Affairs
M. Waller, Manager, Support
M. Daly, Supervisor, Performance Improvement
T. Elwood, Supervisor, Regulatory Affairs & Licensing
G. Hamilton, Supervisor Engineer, Nuclear Engineering
J. Little, Supervisor Engineer, Nuclear Engineering
K. Tipton, Supervisor Engineer, Nuclear Engineering
L. Eitel, Supervisor Engineer, System Engineering
S. Petzel, Engineer, Regulatory Affairs & Licensing
T. Witt, Engineer, Regulatory Affairs & Licensing

NRC Personnel

F. Lyon, Project Manager, Plant Licensing Branch IV-1, NRR

LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED

Opened and Closed

05000483/2014008-01 NCV Failure to Follow Operability Procedure (Section 4OA2.5.a)
05000483/2014008-02 NCV Failure to Analyze for Tornado Missile Strike on Turbine Driven Auxiliary Feedwater Steam Exhaust Piping (Section 4OA2.5.b)

Opened

05000483/2014008-03 URI Emergency Diesel Generator Operability Evaluations using 7 Day Mission Time (Section 4OA5.2.c)

LIST OF DOCUMENTS REVIEWED

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