IR 05000263/2014008

IR 05000263-14-008, February 24 Through March 28, 2014, Monticello, Triennial Fire Protection

ML14119A216
Person / Time
Site:	Monticello
Issue date:	04/29/2014
From:	Robert Daley Engineering Branch 3
To:	Fili K Northern States Power Co
Alan Dahbur
References
IR-14-008
Download: ML14119A216 (29)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION ril 29, 2014

SUBJECT:

MONTICELLO NUCLEAR GENERATING PLANT TRIENNIAL FIRE PROTECTION INSPECTION REPORT 05000263/2014008

Dear Ms. Fili:

On March 28, 2014, the U.S. Nuclear Regulatory Commission (NRC) completed a Triennial Fire Protection Inspection at your Monticello Nuclear Generating Plant. The enclosed inspection report documents the inspection results, which were discussed on March 28, 2014, with Mr. P. Gardner and other members of your staff.

The inspection examined activities conducted under your license as they relate to safety and compliance with the Commissions rules and regulations and with the conditions of your license.

The inspectors reviewed selected procedures and records, observed activities, and interviewed personnel.

The NRC inspectors documented three findings of very-low-safety significance (Green) in this report. These findings were determined to involve violations of NRC requirements. However, because of their very-low-safety significance and because the issues were entered into your Corrective Action Program, the NRC is treating the issues as Non-Cited Violation (NCV) in accordance with Section 2.3.2 of the NRC Enforcement Policy. Additionally, a licensee identified violation is listed in Section 4OA7 of this report.

If you contest the subject or severity of any Non-Cited Violation 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 a copy to the Regional Administrator, U.S. Nuclear Regulatory Commission - Region III, 2443 Warrenville Road, Suite 210, Lisle, IL 60532-4352; the Director, Office of Enforcement, U. S. Nuclear Regulatory Commission, Washington, DC 20555-0001; and the NRC Resident Inspector office at the Monticello Nuclear Generating Plant. In addition, if you disagree with the cross-cutting aspect assigned to any 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, Region III, and the NRC Resident Inspector at the Monticello Nuclear Generating Plant. In accordance with Title 10, Code of Federal Regulations (CFR), Section 2.390 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 NRC Public Document Room or from the Publicly Available Records System (PARS) component of NRC's Agencywide Documents Access and Management System (ADAMS), accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).

Sincerely,

/RA/

Robert C. Daley, Chief Engineering Branch 3 Division of Reactor Safety Docket No. 50-263 License No. DPR-22

Enclosure:

Inspection Report 05000263/2014008 w/Attachment: Supplemental Information

REGION III==

Docket No: 50-263 License No: DPR-22 Report No: 05000263/2014008 Licensee: Northern States Power Company, Minnesota Facility: Monticello Nuclear Generating Plant Location: Monticello, MN Dates: February 24 through March 28, 2014 Inspectors: A. Dahbur, Senior Reactor Inspector (Lead)

D. J. Oliver, Reactor Inspector R. A. Winter, Reactor Engineer Approved by: Robert C. Daley, Chief Engineering Branch 3 Division of Reactor Safety Enclosure

SUMMARY

IR 05000263/2014008; 02/24/2014 - 03/28/2014; Monticello Nuclear Generating Plant; Routine

Triennial Fire Protection Baseline Inspection.

This report covers an announced Triennial Fire Protection Baseline Inspection. The inspection was conducted by Region III inspectors. Three findings were identified by the inspectors. The findings were considered Non-Cited Violations (NCVs) 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 (IMC) 0609, Significance Determination Process (SDP).

Cross-cutting aspects were determined using IMC 0310, Aspects Within the Cross-Cutting Areas. Findings for which the SDP does not apply may be Green or be assigned a severity level after NRC management review. All 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

and Self-Revealed Findings

Cornerstone: Mitigating Systems

Green.

The inspectors identified a finding of very-low-safety significance and associated NCV of 10 CFR Part 50, Appendix R, Section III.G.2 for the licensees failure to ensure that safe shutdown (SSD) equipment were not susceptible to fire induced failures.

Specifically, the licensee failed to ensure that the Drywell Spray Motor Operated Valves MO-2020 and MO-2021 would not spuriously open due to fire induced failures (i.e., open circuit and hot shorts) when they installed shorting switch modifications for these valves.

The licensee entered the issue into their Corrective Action Program and established hourly fire tours in all affected fire areas.

The performance deficiency was determined to be more than minor because the multiple spurious operations of the drywell spray valves could affect safe shutdown of the plant in the event of fire. The finding affected the Mitigating Systems cornerstone. These valves were required to stay in their closed position during a fire event to ensure adequate net positive suction head (NPSH) for safe shutdown pumps. Fire induced circuit failures (i.e., open circuits and hot shorts) on their control cables could result in these valves spuriously opening. The finding represented a low degradation; and therefore, the inspectors determined that the finding screened as having very-low-safety significance (Green) in Task 1.3.1 of IMC 0609, Appendix F. The inspectors determined that the finding had a cross-cutting aspect in the area of Problem Identification and Resolution because the licensee did not thoroughly evaluate issues to ensure that resolutions address causes and extent of conditions commensurate with their safety significance.

Specifically, the licensees evaluation incorrectly concluded that the shorting switch modification would preclude multiple spurious operations of the Drywell Spray valves.

[P.2] (Section 1R05.6(b)(1))

Green.

The inspectors identified a finding of very-low-safety significance and associated NCV of 10 CFR Part 50, Appendix R, Section III.G.1 for the licensees failure to ensure one of the redundant SSD trains located in the same fire area was free of fire damage.

Specifically, both trains of redundant nitrogen bottles used to open and maintain open Safety Relief Valves (SRVs) to depressurize and cooldown the reactor were found located in the same fire area. The licensee entered the issue into their Corrective Action Program and established hourly fire tours in the affected fire areas.

The performance deficiency was determined to be more than minor because the finding was associated with the Mitigating Systems cornerstone attribute of Protection Against External Factors (Fire) and affected the cornerstone objective of ensuring the availability, reliability, and capability of systems that respond to fire events prevent undesirable consequences (i.e., core damage). Specifically, the licensee failed to ensure that one train of nitrogen to supply credited SRVs to achieve and maintain shutdown conditions would be free of fire damage because both trains of nitrogen bottles were located in the same fire area. The finding represented a low degradation and therefore the inspectors determined that the finding screened as having very-low-safety-significance (Green) in Task 1.3.1 of IMC 0609, Appendix F. The finding was not associated with a cross-cutting aspect because the finding was not representative of current performance.

(Section 1R05.6(b)(2))

Green.

The inspectors identified a finding of very-low-safety significance and associated NCV of 10 CFR Part 50, Appendix R, Section III.G.1 for the licensees failure to provide one train of systems necessary to achieve and maintain hot shutdown conditions.

Specifically, the licensee failed to ensure that a sufficient quantity of nitrogen existed from the alternate nitrogen system to supply credited SRVs for the duration that the plant is expected to be in hot shutdown following a fire. Instead, the licensee relied on replacing the nitrogen bottles using a repair procedure. Similarly, the licensee failed to ensure one train of diesel fuel oil transfer system for the emergency diesel generator (EDG) was free of fire damage in the event of a fire. Instead the licensee relied upon repair activities for fuel transfer. The licensee entered the issue into their Corrective Action Program and established hourly fire tours in the affected fire areas.

The performance deficiency was determined to be more than minor because the licensee failed to ensure that safe shutdown equipment and circuits (i.e., alternate nitrogen system and EDG fuel oil) were free of fire damage for the duration that could be expected to maintain hot shutdown conditions following a fire. These repair activities could have potentially affected the plant and operators activities during a challenging fire event. The finding affected the Mitigating Systems cornerstone. The finding represented a low degradation and therefore the inspectors determined that the finding screened as having very-low-safety significance (Green) in Task 1.3.1 of IMC 0609,

Appendix F. The inspectors determined that the finding has a cross-cutting aspect in the area of Human Performance because the licensee did not recognize and plan for the possibility of mistakes, latent issues, and inherent risk, even while expecting successful outcomes. Individuals did not implement appropriate error reduction tools. [H.12]

(Section 1R05.9(b)(1))

Licensee-Identified Violations

Violations of very-low-safety significance or severity Level IV that were identified by the licensee have been reviewed by the inspectors. Corrective actions taken or planned by the licensee have been entered into the licensees Corrective Action Program. These violations and corrective action tracking numbers are listed in Section 4OA7 of this report.

REPORT DETAILS

REACTOR SAFETY

Cornerstones: Initiating Events and Mitigating Systems

1R05 Fire Protection

The purpose of the Fire Protection Triennial Baseline Inspection was to conduct a design-based, plant specific, risk-informed, onsite inspection of the licensees Fire Protection Programs defense-in-depth elements used to mitigate the consequences of a fire. The Fire Protection Program shall extend the concept of defense-in-depth to fire protection in plant areas important to safety by:

• preventing fires from starting;

• rapidly detecting, controlling and extinguishing fires that do occur;

• providing protection for structures, systems, and components important to safety so that a fire that is not promptly extinguished by fire suppression activities will not prevent the safe-shutdown of the reactor plant; and

• taking reasonable actions to mitigate postulated events that could potentially cause loss of large areas of power reactor facilities due to explosions or fires.

The inspectors evaluation focused on the design, operational status, and material condition of the reactor plants Fire Protection Program, post-fire safe shutdown systems, and B.5.b mitigating strategies. The objectives of the inspection were to assess whether the licensee had implemented a Fire Protection Program that:

(1) provided adequate controls for combustibles and ignition sources inside the plant;

(2) provided adequate fire detection and suppression capability;

(3) maintained passive fire protection features in good material condition;

(4) established adequate compensatory measures for out-of-service, degraded or inoperable fire protection equipment, systems or features;

(5) ensured that procedures, equipment, fire barriers and systems exist so that the post-fire capability to safely shutdown the plant was ensured;

(6) included feasible and reliable operator manual actions when appropriate to achieve safe shutdown; and

(7) identified fire protection issues at an appropriate threshold and ensured these issues were entered into the licensees Problem Identification and Resolution Program.

In addition, the inspectors review and assessment focused on the licensees post-fire safe shutdown systems for selected risk significant fire areas. Inspector emphasis was placed on determining that the post-fire safe shutdown capability and the fire protection features were maintained free of fire damage to ensure that at least one post-fire safe shutdown success path was available. The inspectors review and assessment also focused on the licensees B.5.b related license conditions and the requirements of Title 10, Code of Federal Regulations (10 CFR) Part 50.54 (hh)(2). Inspector emphasis was to ensure that the licensee could maintain or restore core cooling, containment, and spent fuel pool cooling capabilities utilizing the B.5.b mitigating strategies following a loss of large areas of power reactor facilities due to explosions or fires. Documents reviewed are listed in the Attachment to this report.

The fire areas and B.5.b mitigating strategies selected for review during this inspection are listed below and in Section 1R05.13. The fire areas selected constituted three inspection samples and the B.5.b mitigating strategies selected constituted two inspection samples, respectively, as defined in Inspection Procedure (IP) 71111.05T.

Fire Area Fire Zone Description 23A, 14B, 13C, IX Intake Structure and MCC 133/Feedwater Pump Area and 19C XI 15E Diesel Fuel Oil Transfer Pump House XXII 31B and 32B EFT Building

.1 Protection of Safe Shutdown Capabilities

a. Inspection Scope

For each of the selected fire areas, the inspectors reviewed the fire hazards analysis, safe shutdown analysis, and supporting drawings and documentation to verify that safe shutdown capabilities were properly protected.

The inspectors also reviewed the licensees design control procedures to ensure that the process included appropriate reviews and controls to assess plant changes for any potential adverse impact on the Fire Protection Program and/or post-fire safe shutdown analysis and procedures.

b. Findings

No findings of significance were identified.

.2 Passive Fire Protection

a. Inspection Scope

For the selected fire areas, the inspectors evaluated the adequacy of fire area barriers, penetration seals, fire doors, electrical raceway fire barriers, and fire rated electrical cables. The inspectors observed the material condition and configuration of the installed barriers, seals, doors, and cables. The inspectors reviewed approved construction details and supporting fire tests. In addition, the inspectors reviewed license documentation, such as NRC safety evaluation reports, and deviations from NRC regulations and the National Fire Protection Association (NFPA) standards to verify that fire protection features met license commitments.

The inspectors walked down accessible portions of the selected fire areas to observe material condition and the adequacy of design of fire area boundaries (including walls, fire doors, and fire dampers) to ensure they were appropriate for the fire hazards in the area.

The inspectors reviewed the installation, repair, and qualification records for a sample of penetration seals to ensure the fill material was of the appropriate fire rating and that the installation met the engineering design.

b. Findings

No findings of significance were identified.

.3 Active Fire Protection

a. Inspection Scope

For the selected fire areas, the inspectors evaluated the adequacy of fire suppression and detection systems. The inspectors observed the material condition and configuration of the installed fire detection and suppression systems. The inspectors reviewed design documents and supporting calculations. In addition, the inspectors reviewed license basis documentation, such as, NRC safety evaluation reports, deviations from NRC regulations, and NFPA standards to verify that fire suppression and detection systems met license commitments.

b. Findings

No findings of significance were identified.

.4 Protection from Damage from Fire Suppression Activities

a. Inspection Scope

For the selected fire areas, the inspectors verified that redundant trains of systems required for hot shutdown would not be subject to damage from fire suppression activities or from the rupture or inadvertent operation of fire suppression systems including the effects of flooding. The inspectors conducted walkdowns of each of the selected fire areas to assess conditions such as the adequacy and condition of floor drains, equipment elevations, and spray protection.

b. Findings

No findings of significance were identified.

.5 Alternative Shutdown Capability

a. Inspection Scope

The inspectors reviewed the licensees systems required to achieve alternative safe shutdown to determine if the licensee had properly identified the components and systems necessary to achieve and maintain safe shutdown conditions. The inspectors also focused on the adequacy of the systems to perform reactor pressure control, reactivity control, reactor coolant makeup, decay heat removal, process monitoring, and support system functions.

The inspectors conducted selected area walkdowns to determine if operators could reasonably be expected to perform the alternate safe shutdown procedure actions and that equipment labeling was consistent with the alternate safe shutdown procedure. The review also looked at operator training, as well as consistency between the operations shutdown procedures and any associated administrative controls.

b. Findings

No findings of significance were identified.

.6 Circuit Analyses

a. Inspection Scope

The inspectors verified that the licensee performed a post-fire safe shutdown (SSD)analysis for the selected fire areas and the analysis appropriately identified the structures, systems, and components important to achieving and maintaining safe shutdown. Additionally, the inspectors verified that the licensee's analysis ensured that necessary electrical circuits were properly protected and that circuits that could adversely impact safe shutdown due to hot shorts, shorts to ground, or other failures were identified, evaluated, and dispositioned to ensure spurious actuations would not prevent safe shutdown.

The inspectors' review considered fire and cable attributes, potential undesirable consequences, and common power supply/bus concerns. Specific items included the credibility of the fire threat, cable insulation attributes, cable failure modes, and actuations resulting in flow diversion or loss of coolant events.

The inspectors also reviewed cable raceway drawings for a sample of components required for post-fire safe shutdown to verify that cables were routed as described in the cable routing matrices.

The inspectors reviewed circuit breaker coordination studies to ensure equipment needed to conduct post-fire safe shutdown activities would not be impacted due to a lack of coordination. Additionally, the inspectors reviewed a sample of circuit breaker maintenance records to verify that circuit breakers for components required for post-fire safe shutdown were properly maintained in accordance with procedural requirements.

The inspectors verified for cables that are important to SSD, but not part of the success path, and that do not meet the separation/protection requirements of Section III.G.2 of 10 CFR Part 50, Appendix R, that the circuit analysis considered the cable failure modes. In addition, the inspectors have verified that the licensee has either (1)determined that there is not a credible fire scenario (through fire modeling), (2)implemented feasible and reliable manual actions to assure SSD capability, or (3)performed a circuit fault analysis demonstrating no potential impact on SSD capability exists.

b. Findings

(1) Shorting Switch Modification Failed to Ensure Drywell Spray Valves would not Spuriously Open

Introduction:

The inspectors identified a finding of very-low-safety significance (Green)and associated Non-Cited Violation of 10 CFR Part 50, Appendix R, Section III.G.2 for the licensees failure to ensure that safe shutdown equipment were not susceptible to fire induced failures. Specifically, the licensee implemented a modification and installed shorting switches to preclude the spurious operation of the Drywell Spray Motor Operated Valves MO-2020 and MO-2021. The inspectors reviewed the circuits for these valves and determined that even with the installed shorting switch modification, these valves could still spuriously open due to fire induced failures (i.e., open circuit and hot shorts) in the event of a fire in several fire areas.

Description:

The licensee completed a multiple spurious operations (MSO) evaluation which included plant specific and the Boiling Water Reactor (BWR) scenarios listed in the Nuclear Energy Institute (NEI) 00-01, Revision 2, Guidance for Post-Fire Safe Shutdown Circuit

Analysis.

BWR Generic MSO 4r described a scenario for Containment Over Pressure (COP) and the loss of net positive suction head (NPSH)due to spurious initiation of containment sprays. The licensees evaluation for this scenario indicated that the thermal-hydraulic analysis performed under Engineering Changes EC-20901 and EC-20902 (NPSH and Inventory) determined that the diversion of Residual Heat Removal (RHR) to the drywell spray system would have an adverse effect on Monticellos safe shutdown analysis. The analysis concluded that the spurious operation of the spray valve flow-path must be prevented from occurring since the resultant cooling effect on the drywell had the potential to reduce the available NPSH below the required NPSH for safe shutdown pumps.

Drywell spray included two divisions of inboard and outboard motor operated valves, MO-2020 is in series with MO-2022 for Division I and MO-2021 is in series with MO-2023 for Division II. These valves are normally closed during plant operations and their switches are in AUTO position. Two of the drywell spray valves in series needed to spuriously open to result in a reduction in the available NPSH for safe shutdown pumps.

Therefore, the licensee performed a plant modification under EC-20669 MO-2020 and MO-2021 Shorting Switch and installed shorting switches on drywell spray valves MO-2020 and MO-2021 to preclude spurious opening of these valves during RHR operation during a fire event.

Modification EC-20669 installed a shorting circuit using control room switches 10A-S9A/B for RHR valves MO-2020 and MO-2021, respectively. The installation of the shorting circuit was to ensure that the RHR Drywell Spray Outboard Valves, MO-2020 and MO-2021, remained in their normal closed position in the event of a fire. This was accomplished by shorting the open coil of the Motor Control Center (MCC) Contactor (42-O) when the control room switches were in the AUTO position and the operators were not actively changing the valve position. Internal panel wiring was installed in the control room to connect existing control board switches 10A-S9A/B, Contact 4-4T, to the panel terminal blocks. Contact 4-4T is open when the switch was in the OPEN, CLOSE, or intermediate positions, but closed when the switch spring returns to the AUTO position.

The licensee performed a shorting switch considerations evaluation and determined that even after the implementation of the shorting switch modification; a multiple hot short scenario would still exist in theory which could spuriously open these RHR valves to their undesired position. Specifically, if a fire induced open circuit were to occur on one conductor, in conjunction with a hot short occurring on another conductor, the valves could spuriously open. However, the licensee concluded, based on testing performed under NRC/EPRI (NUREG/CR-7150 Volume 1), preclusion of spurious operation by means of a shorting switch, as installed by EC-20669, was not vulnerable to defeat by any observed, or credible postulated failure scenario, since the control power circuitry for both RHR valves was 120 VAC. The licensee determined that based on data from the testing performed by NRC/EPRI, fire induced open circuits for control level cables were often found to occur for DC powered circuitry but not for AC powered circuitry.

The inspectors reviewed the modification, circuit diagrams for these valves, and licensee evaluation and determined that the circuits design for these RHR valves did not comply with the Appendix R regulation, since fire induced failures (i.e., open circuit and hot shorts on circuits) associated with the two in series spray valves could result in the opening of both valves and the reduction of the NPSH for safe shutdown pumps. A fire induced open circuit on one conductor (marked U) in conjunction with a hot short on another conductor (marked 1F) could result in the opening of MO-2020, similarly for MO-2022. Therefore, the inspectors determined, based on the cable routing associated with these valves, multiple spurious operation of the drywell spray valves could occur in several fire areas including alternate shutdown areas, (i.e., the control room and the cable speeding room) and non-alternate shutdown areas, (i.e., MCC Room and turbine building).

Based upon discussions with the inspectors, the licensee entered this issue into their Corrective Action Program as AR 01424459 Potential Violation for Using MSO Shorting Switch, and established fire rounds in all affected fire areas.

Analysis:

The inspectors determined that the failure to ensure one train remained free from fire damage for a system credited to achieve and maintain hot shutdown conditions in a fire event was contrary to the requirements of 10 CFR Part 50, Appendix R, Section III.G.2, and was a performance deficiency. Specifically, the licensee failed to preclude multiple spurious operations of the drywell spray valves from occurring in the event of a fire.

The performance deficiency was determined to be more than minor because it was associated with the Mitigating Systems cornerstone attribute of Protection Against External Events (Fire) and affected the cornerstone objective of ensuring the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences (i.e., core damage). Specifically, the multiple spurious operations of the drywell spray valves would affect safe shutdown of the plant in the event of a fire. These valves were required to stay in their closed position during a fire event to ensure adequate NPSH for safe shutdown pumps. Fire induced circuit failures (i.e., open circuits and hot shorts) on their control cables could result in spurious opening of these valve.

In accordance with IMC 0609, Significance Determination Process, Attachment 0609.04, Phase I - Initial Characterization of Findings, Table 3, the inspectors determined that the finding affected the ability to reach or maintain safe shutdown conditions in case of a fire. Therefore, screening under IMC 0609, Appendix F, Fire Protection Significance Determination Process, was required.

The inspectors determined that the finding affected the post-fire safe shutdown finding category. The inspectors determined that the finding represented a low degradation because the likelihood of this type of combination of fire induced circuit failures to occur that would result in multiple spurious operations of a two series drywell spray valves was very low. A hot short on control circuitry for MO-2022 and an open circuit on one of the conductors in conjunction with a hot short on another conductor for the control circuitry of MO-2020 had to occur to have an effect on the safe shutdown of the plant in the event of a fire, similarly for MO-2021 and MO-2023 for Division II. Therefore, the inspectors determined that the finding screened as having very-low-safety significance (Green) in Task 1.3.1 of IMC 0609, Appendix F.

This finding has a cross-cutting aspect in the area of Problem Identification and Resolution, because the licensee did not thoroughly evaluate issues to ensure that resolutions address causes and extent of conditions commensurate with their safety significance. Specifically, the licensees evaluation incorrectly concluded that the shorting switch modification complied with the Appendix R requirements to preclude multiple spurious operations of the Drywell Spray valves. [P.2].

Enforcement:

Title 10 CFR 50.48(b)(2) requires, in part, that all nuclear power plants licensed to operate prior to January 1, 1979, must satisfy the applicable requirements of Appendix R to this part, including specifically the requirements of Sections III.G,Section III.J, and Section III.O.Section III.G.2 of 10 CFR Part 50, Appendix R, states, in part that except as provided for in Paragraph G.3 of this section, where cables and equipment, including associated non-safety circuits that could prevent operation or cause mal-operation due to hot shorts, open circuits, or shorts to ground, of redundant trains of systems necessary to achieve and maintain hot shutdown conditions are located within the same fire area outside of primary containment, means of ensuring that one of the redundant trains is free of fire damage shall be provided.

Contrary to the above, as of March 28, 2014, the licensee did not provide means of ensuring that one of the redundant trains was free of fire damage, by failing to ensure that circuits that could cause mal-operation of redundant trains of systems necessary to achieve hot shutdown conditions due to hot shorts, open circuits or short to ground free of fire damage. Specifically, the licensee failed to ensure the RHR Drywell Spray valves MO-2020, MO-2022 and MO-2021, MO-2023 for Division I and II respectively, were free of fire damage and would not spuriously open due to a fire induced circuit failures. The shorting switch modification installed per EC-290669 did not ensure that these valves would remain in their safe shutdown closed position in the event of a fire. Because this violation was of very-low-safety significance and it was entered into the licensees Corrective Action Program as AR 01424459, this violation is being treated as an NCV, consistent with Section 2.3.2 of the NRC Enforcement Policy (NCV 05000263/2014008-01, Shorting Switch Modification Failed to ensure Drywell Spray Valves would not Spuriously Open).

(2) Both Redundant Safe Shutdown Trains of Nitrogen Bottles were Found Located In the Same Fire Area

Introduction:

The inspectors identified a finding of very-low-safety significance (Green)and associated Non-Cited Violation of 10 CFR Part 50, Appendix R, Section III.G.1 for the licensees failure to ensure one of the redundant safe shutdown (SSD) trains located in the same fire area was free of fire damage. Specifically, the licensee had placed in the same fire area both trains of redundant nitrogen bottles used to open and maintain open Safety Relief Valves (SRV) to depressurize and cooldown. At least two SRVs were required to achieve and maintain safe shutdown conditions. The use of nitrogen bottles as the Alternate Nitrogen System to supply and control SRVs was the credited for post-fire SSD method.

Description:

During the inspectors walkdown in Fire Area XII, the inspectors discovered that both trains of redundant nitrogen bottles used as the credited method to open and maintain open the SRVs were located in this fire area. Additionally, the licensee had stored in the same fire area eight nitrogen bottles as replacements for the four bottle trains to assure sufficient operational time for multiple cycling of the SRVs to accomplish safe shutdown. These nitrogen bottles were part of the Alternate Nitrogen System to supply the credited SRVs used to depressurize and cooldown. The Safe Shutdown Analysis showed that Division I safe shutdown equipment were credited to safely shutdown the plant in the event of a fire in Fire Area XII. The analysis credited the Alternate Nitrogen Supply for pneumatic motive power for SRVs E/F/H and SRV G from its accumulator. The inspectors were concerned that a fire in Fire Area XII could render all nitrogen bottles for both trains nonfunctional since they were all located in the same fire area.

The licensee entered this condition into their Corrective Action Program as AR 01424477, Appendix R Fire Strategy for Fire Area XII Incorrect, and established hourly roving fire watches as compensatory measures for this non-compliance. The licensee also performed a preliminary circuit analysis for all SRVs and concluded that a fire in Fire Area XII could affect cabling associated with solenoid valves SV-4234 and SV-4235 for the Alternate Nitrogen Supply since a hot short occurring on cables to these solenoid valves could close these valves resulting in a loss of nitrogen supply to SRVs E/F/H for Division I and Division II. The licensees preliminary evaluation also concluded that it appeared that SRV G and SRV D associated with Division I and Division II respectively could be free of fire damage in the event of a fire in Fire Area XII. The SRV D and SRV G each had accumulators, which were not located in Fire Area XII and each had sufficient volumes of nitrogen to last 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> based on the leak rates from the latest surveillance. The current safe shutdown analysis and procedures did not credit SRV D for safe shutdown of the plant in the event of a fire in Fire Area XII. In addition a formal analysis of the circuit and its associated supporting power supply for SRV D was not available to ensure the availability of SRV D in the event of a fire in this area since the existing analysis assumed the loss of safe shutdown Division II equipment and originally only relied on Division I safe shutdown equipment.

Analysis:

The inspectors determined that the licensees failure to ensure one train remained free from fire damage for a system necessary to achieve and maintain hot shutdown conditions was contrary to 10 CFR Part 50, Appendix R, Section III.G.1 and was a performance deficiency. Specifically, both trains of nitrogen bottles used for the Alternate Nitrogen System were located in the same fire area, where a fire in Fire Area XII could damage both trains of nitrogen bottles. The Alternate Nitrogen System was credited as a pneumatic source of motive pressure for the SRVs which were credited for safe shutdown in the event of a fire.

The performance deficiency was determined to be more than minor because the finding was associated with the Mitigating Systems cornerstone attribute of Protection Against External Factors (Fire) and affected the cornerstone objective of ensuring the availability, reliability, and capability of systems that respond to fire events prevent undesirable consequences (i.e., core damage). Specifically, the licensee failed to ensure that one train of nitrogen to supply credited SRVs to achieve and maintain shutdown conditions would be free of fire damage because both trains of nitrogen bottles were located in the same fire area. Although, the licensees preliminary evaluation showed that SRV D and SRV G could be available for safe shutdown, the existing analysis and procedures did not credit SRV D for safe shutdown of the plant in the event of a fire in Fire Area XII.

The absence of full analysis for the circuits associated with SRV D and procedure steps crediting SRV D did not ensure the availability and reliability of SRV D to be credited for safe shutdown in the event of a fire in Fire Area XII.

In accordance with IMC 0609, Significance Determination Process, Attachment 0609.04, Initial Characterization of Findings, Table 2 the inspectors determined the finding affected the Mitigating Systems cornerstone. The finding degraded fire protection defense-in-depth strategies, and the inspectors determined, using Table 3, that it could be evaluated using Appendix F, Fire Protection Significance Determination Process.

The inspectors determined that the finding affected the post-fire safe shutdown finding category. The inspectors determined that the finding represented a low degradation because the licensee's preliminary evaluation indicated that it appeared that two SRVs D and G and their associated accumulators would not be affected in a fire in Fire Area XII. SRV D was not originally credited in the SSD for a fire in this area.

Therefore, the inspectors determined that the finding screened as having very-low-safety significance (Green) in Task 1.3.1 of IMC 0609, Appendix F as the reactor would be able to reach and maintain safe shutdown conditions.

The inspectors did not identify a cross-cutting aspect associated with this finding because the finding was not representative of current performance.

Enforcement:

Title 10 CFR Part 50, Appendix R, Section III.G.1 requires that fire protection features be provided for structures, systems, and components important to safe shutdown. These features shall be capable of limiting fire damage so that: one train of systems necessary to achieve and maintain hot shutdown conditions from either the control room or emergency control stations is free of fire damage.

Contrary to the above, as of March 26, 2014, the licensee failed to provide fire protection features for components important to safe shutdown to limit fire damage so that one train was free of damage. Specifically, the licensee failed to ensure that one train of nitrogen bottles credited to supply SRVs to achieve and maintain shutdown conditions was free of fire damage because both trains of nitrogen bottles were located in the same Fire Area XII. In addition the location of these bottles did not meet any of the means described in Appendix R,Section III.G.2. Because this violation was of very-low-safety significance and it was entered into the licensee's Corrective Action Program as AR 0124477, this violation is being treated as an NCV, consistent with Section 2.3.2 of the NRC Enforcement Policy (NCV 05000263/2014008-02, Failure to Ensure One of the Redundant Safe Shutdown Trains Located In the Same Fire Area Is Free of Fire Damage).

.7 Communications

a. Inspection Scope

The inspectors reviewed, on a sample basis, the adequacy of the communication system to support plant personnel in the performance of alternative safe shutdown functions and fire brigade duties. The inspectors verified that plant telephones, page systems, sound powered phones, and radios were available for use and maintained in working order.

The inspectors reviewed the electrical power supplies and cable routing for these systems to verify that either the telephones or the radios would remain functional following a fire.

b. Findings

No findings of significance were identified.

.8 Emergency Lighting

a. Inspection Scope

The inspectors performed a plant walkdown of selected areas in which a sample of operator actions would be performed in the performance of alternative safe shutdown functions. As part of the walkdowns, the inspectors focused on the existence of sufficient emergency lighting for access and egress to areas and for performing necessary equipment operations. The locations and positioning of the emergency lights were observed during the walkdown and during review of manual actions implemented for the selected fire areas.

b. Findings

No findings of significance were identified.

.9 Cold Shutdown Repairs

a. Inspection Scope

The inspectors reviewed the licensees procedures to determine whether repairs were required to achieve cold shutdown and to verify that dedicated repair procedures, equipment, and material to accomplish those repairs were available onsite. The inspectors also evaluated whether cold shutdown could be achieved within the required time using the licensee's procedures and repair methods. The inspectors also verified that equipment necessary to perform cold shutdown repairs was available onsite and properly staged.

b. Findings

(1) Repairs Credited for Hot Shutdown Conditions

Introduction:

The inspectors identified a finding of very-low-safety significance (Green)and associated Non-Cited Violation of 10 CFR Part 50, Appendix R, Section III.G.1 for the licensees failure to provide one train of systems necessary to achieve and maintain hot shutdown conditions. Specifically, the licensee failed to ensure that a sufficient quantity of nitrogen existed from the Alternate Nitrogen System to supply credited SRVs for the duration that the plant was expected to be in hot shutdown following a fire.

Instead, the licensee relied on replacing the nitrogen bottles using a repair procedure.

Similarly, the licensee failed to ensure one train of the diesel fuel oil transfer system was free of fire damage in the event of a fire; instead the licensee relied upon repair activities for fuel transfer.

Description:

During a review of the licensees Procedure C.4-C; Shutdown Outside Control Room, Revision 41, inspectors noted that the licensee used a combination of SRVs and low pressure systems (Core Spray) as the credited means for achieving cold shutdown conditions. Monticello USAR Appendix J.04; Safe Shutdown Analysis, Section J.4.4.2 describes these systems as the facilitys means of achieving both hot and cold shutdown conditions to meet the requirements of 10 CFR Part 50, Appendix R.

Monticellos SRVs required a pneumatic source of motive pressure to provide operators with the ability to manually open SRVs as necessary to reduce reactor pressure sufficiently to allow for Core Spray (CS) to maintain reactor water level above the top of active fuel (TAF). The credited source of pressure during such events is nitrogen supplied from the Alternate Nitrogen System. Procedure C.4-C required plant operators to monitor the Alternate Nitrogen System every 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> following an appendix R fire event, and replace depleted cylinders as necessary. The basis for this, and other steps concerning the available quantity of nitrogen available from the Alternate Nitrogen System, was contained in calculation CA-94-017; Calculation of Alternate Nitrogen System Supply Pressure and Spare Bottle Inventory. Inspectors found that CA-94-017 indicated that the time between an acceptable bottle supply pressure value and completion of the bottle change during a postulated 10 CFR Part 50, Appendix R fire was 17 hours1.967593e-4 days <br />0.00472 hours <br />2.810847e-5 weeks <br />6.4685e-6 months <br />.

The inspectors noticed that Monticello credited two repair activities that included the replacement of nitrogen bottles per Operation Manual B.08.04.03-05 and the restoration of fuel oil transfer capability to Division I emergency diesel generator (EDG) per Operation Manual B.08.11-05. These repair activities were evaluated per Fire Protection Engineering Evaluation (FPEE-11-001), completed in February 4, 2011. The FP engineering evaluation concluded that since the plant would be obtaining cold safe shutdown (less than 212 degrees Fahrenheit) at approximately 13 hours1.50463e-4 days <br />0.00361 hours <br />2.149471e-5 weeks <br />4.9465e-6 months <br /> per CA-11-174; Task Report T0611 Appendix R Fire Protection, and the Alternate Nitrogen System would last approximately 17 hours1.967593e-4 days <br />0.00472 hours <br />2.810847e-5 weeks <br />6.4685e-6 months <br />, the replacement of the alternate nitrogen bottles is a cold shutdown repair which met Appendix R requirements. The supply of fuel oil contained in the EDG base and day tanks supplied a fully loaded EDG for approximately 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. Fire in Division II areas resulting in a loss of offsite power would require replenishment of Division I EDG fuel oil. Although the replenishment of fuel oil needed to be accomplished prior to the plant reaching cold safe shutdown, the licensees FP engineering evaluation concluded the activities met the Appendix R requirement for cold shutdown repair.

Corrective action AR 01358943 EPU Time to Cold Shutdown Change, identified that the capability to obtain cold shutdown in 13 hours1.50463e-4 days <br />0.00361 hours <br />2.149471e-5 weeks <br />4.9465e-6 months <br /> as specified in CA-11-174 could not be met. A revised analysis per calculation, CA-12-049; Monticello Appendix R MSO Thermal-Hydraulic Analysis - Time to Reach Cold Shutdown, Revision 0, revealed that the time to reach cold shutdown conditions was up to approximately 42 hours4.861111e-4 days <br />0.0117 hours <br />6.944444e-5 weeks <br />1.5981e-5 months <br />.

The inspectors concluded that the calculated quantity of nitrogen available from the Alternate Nitrogen System was insufficient to meet what was required to bring the plant to cold shutdown conditions. Per the revised analysis, the replenishment of expended bottles constituted a repair during the timeframe that the plant was in hot shutdown. The inspectors disagreed with the licensees conclusion that these repair activities met the Appendix R requirement, since these repairs to equipment were required to maintain hot shutdown conditions. The Alternate Nitrogen System was used for SRV operation which was needed to maintain hot shutdown conditions until cold shutdown was achieved.

Similarly, EDG fuel oil was needed for EDG operations to provide AC power to pumps and equipment needed to maintain hot shutdown until the cold shutdown was achieved.

On March 27, 2014, the licensee initiated AR 01424451; Nitrogen Bottle Replacement Cold Shutdown Repair which described the SRVs as non-conforming with 10 CFR Part 50, Appendix R and included actions to perform a functionality assessment, and to resolve the non-conforming condition. Similarly, the licensee documented the repair activities for the EDG fuel oil transfer capability as a hot shutdown repair in AR 01421712; Portable Diesel Fuel Oil Transfer Pump Cold Shutdown.

Analysis:

The inspectors determined that the failure to provide one train of systems necessary to achieve and maintain hot shutdown conditions without repair was contrary to 10 CFR Part 50, Appendix R, Section III.G.1 and was a performance deficiency.

Specifically, repairs in the form of replacing depleted nitrogen bottles for the Alternate Nitrogen System and replenishment of EDG fuel oil which were necessary to maintain hot shutdown conditions did not meet the Appendix R requirements. Repairs of equipment and circuits required to maintain hot shutdown conditions are not permitted without prior NRC approval.

The performance deficiency was determined to be more than minor because the finding was associated with the Mitigating Systems cornerstone attribute of Protection Against External Factors (Fire) and affected the cornerstone objective of ensuring the availability, reliability, and capability of systems that respond to fire events to prevent undesirable consequences. Specifically, the licensee failed to ensure that safe shutdown equipment and circuit (i.e., Alternate Nitrogen System and EDG fuel oil transfer system) were free of fire damage for the duration that could be expected to maintain hot shutdown conditions following a fire. These repair activities could have potentially affected the plant and Operators activities during a challenging fire event.

In accordance with IMC 0609, Significance Determination Process, Attachment 0609.04, Initial Characterization of Findings, Table 2 the inspectors determined the finding affected the Mitigating Systems cornerstone. The finding degraded fire protection defense-in-depth strategies, and the inspectors determined, using Table 3, that it could be evaluated using Appendix F, Fire Protection Significance Determination Process.

The inspectors verified that the repair activities were documented in procedures and the repair equipment was maintained and available onsite. Although the inspectors determined that the repair activities could have potentially challenged safe shutdown, the finding represented a low degradation and was screened as having very-low-safety significance (Green) in Task 1.3.1 of IMC 0609, Appendix F because the repair activities in place, reasonably would have maintained safe shutdown conditions and were reasonably achievable.

This finding has a cross-cutting aspect in the area of Human Performance because the licensee did not recognize and plan for the possibility of mistakes, latent issues, and inherent risk, even while expecting successful outcomes. Individuals did not implement appropriate error reduction tools. Specifically, the failure to provide one train of systems necessary to achieve and maintain hot shutdown conditions from either the control room or alternate shutdown station without repair was a result of an overstated position that the licensee would not maintain hot shutdown conditions, but would immediately take steps to achieve cold shutdown and that once those steps were in progress, repairs to components necessary to achieve and maintain cold shutdown could be initiated. [H.12]

Enforcement:

Title 10 CFR Part 50, Appendix R, Section III.G.1 requires that fire protection features be provided for structures, systems, and components important to safe shutdown. These features shall be capable of limiting fire damage so that:

a) one train of systems necessary to achieve and maintain hot shutdown conditions from either the control room or emergency control station(s) is free of fire damage; and b) systems necessary to achieve and maintain cold shutdown from either the control room or emergency control system(s) can be repaired within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

Contrary to the above, as of March 28, 2014, the licensee failed to provide fire protection features to limit fire damage so that one train of systems necessary to achieve and maintain hot shutdown condition was free of fire damage. Specifically, the quantity of nitrogen available from the Alternate Nitrogen System was insufficient to meet that required to bring the plant to cold shutdown conditions without the need for replenishing expended bottles, which constituted a repair during the timeframe that the plant remains in hot shutdown. This was similar to the need for replenishment of the EDG fuel oil transfer system after fire damage.

Because this violation was of very-low-safety significance and it was entered into the licensees Corrective Action Program as AR 01424451 and AR 01421712, this violation is being treated as an NCV, consistent with Section 2.3.2 of the NRC Enforcement Policy (NCV 05000263/2014008-03, Repairs Credited for Hot Shutdown Conditions).

.10 Compensatory Measures

a. Inspection Scope

The inspectors conducted a review to verify that compensatory measures were in place for out-of-service, degraded or inoperable fire protection and post-fire safe shutdown equipment, systems, or features (e.g., detection and suppression systems, and equipment, passive fire barriers, pumps, valves or electrical devices providing safe shutdown functions or capabilities). The inspectors also conducted a review of the adequacy of short term compensatory measures to compensate for a degraded function or feature until appropriate corrective actions were taken.

b. Findings

No findings of significance were identified.

.11 Review and Documentation of Fire Protection Program Changes

a. Inspection Scope

The inspectors reviewed changes to the approved Fire Protection Program to verify that the changes did not constitute an adverse effect on the ability to safely shutdown. The inspectors also reviewed the licensees design control procedures to ensure that the process included appropriate reviews and controls to assess plant changes for any potential adverse impact on the Fire Protection Program and/or post-fire safe shutdown analysis and procedures.

b. Findings

No findings of significance were identified.

.12 Control of Transient Combustibles and Ignition Sources

a. Inspection Scope

The inspectors reviewed the licensee's procedures and programs for the control of ignition sources and transient combustibles to assess their effectiveness in preventing fires and in controlling combustible loading within limits established in the fire hazards analysis. A sample of hot work and transient combustible control permits were also reviewed. The inspectors performed plant walkdowns to verify that transient combustibles and ignition sources were being implemented in accordance with the administrative controls.

b. Findings

No findings of significance were identified

.13 B.5.b Inspection Activities

a. Inspection Scope

The inspectors reviewed the licensees preparedness to handle large fires or explosions by reviewing selected mitigating strategies. This review ensured that the licensee continued to meet the requirements of their B.5.b related license conditions and 10 CFR 50.54(hh)(2) by determining that:

• Procedures were being maintained and adequate;

• Equipment was properly staged, maintained, and tested;

• Station personnel were knowledgeable and could implement the procedures; and

• Additionally, inspectors reviewed the storage, maintenance, and testing of B.5.b related equipment.

The inspectors reviewed the licensees B.5.b related license conditions and evaluated selected mitigating strategies to ensure they remain feasible in light of operator training, maintenance/testing of necessary equipment and any plant modifications. In addition, the inspectors reviewed previous inspection reports for commitments made by the licensee to correct deficiencies identified during performance of Temporary Instruction (TI) 2515/171 or subsequent performances of these inspections.

The B.5.b mitigating strategies selected for review during this inspection are listed below. The offsite and onsite communications, notifications/emergency response organization activation, initial operational response actions and damage assessment activities identified in Table A.3 1 of Nuclear Energy Institute (NEI) 06-12, B.5.b Phase II and Phase III Submittal Guidance, Revision 2 are evaluated each time due to the mitigation strategies scenario selected.

NEI 06-12, Revision 2, Section Licensee Strategy (Table)3.4.1 Manual Operation of RCIC A 2.6 Fire System Management Strategies

b. Findings

No findings of significance were identified.

4OA2 Identification and Resolution of Problems

a. Inspection Scope

The inspectors reviewed the licensees Corrective Action Program procedures and samples of corrective action documents to verify that the licensee was identifying issues related to the Fire Protection Program at an appropriate threshold and entering them in the Corrective Action Program. The inspectors reviewed selected samples of condition reports, design packages, and fire protection system non-conformance documents.

b. Findings

No findings of significance were identified.

4OA6 Management Meetings

.1 Exit Meeting Summary

On March 28, 2014, the inspectors presented the inspection results to Mr. P. Gardner, and other members of the licensee staff. The licensee acknowledged the issues presented. The inspectors confirmed that none of the potential report input discussed was considered proprietary.

4OA7 Licensee-Identified Violations

The following violation of very-low-safety significance (Green) was identified by the licensee and is a violation of NRC requirements, which meets the criteria of the NRC Enforcement Policy for being dispositioned as an NCV.

• On March 14, 2014, the licensee identified Combustible material in the exclusion area in the Torus without a Transient Combustible Permit. Torus bay 16 had ceiling barrier material crumbling and falling that possibly was asbestos. White Herculite and red tape was used as a catching platform to contain the ceiling material. The exclusion area is large and 3 bays separation exist between the combustible material and the area containing the opposite train. Combustible loading even with the additional combustible material was approximately 11 BTU/square-foot. The addition of combustible material without a transient combustible permit was contrary to NCV of License Condition 2.C.4, Fire Protection, requiring implementing an approved Fire Protection Program (FPP) as described in the Final Safety Analysis Report as amended. The licensee failed to implement the requirements as specified in their fire protection program per procedure FP-PE-CC-01, Combustible Control, Revision 1, which required a continuous fire watch if combustible were to be put in the exclusion fire zone without a permit. The licensee performed a preliminary assessment and concluded that even with the presence of the combustible material in the zone; a fire in the area would not impact both safe shutdown trains. Therefore, the inspectors determined that the finding was of very-low-safety significance (Green) because of the large separation between the opposite trains. This issue was entered into the licensees Corrective Action Program as AR 1422495, Combustibles Found in the Exclusion Area in the Torus, dated March 14, 2014. As part of the licensees corrective actions, the licensee added this temporary combustible load to the Combustible Loading Control logs, initiated a Combustible Control Permit and initiated a temporary change to FP-PE-CC-01, Combustible Control, that allowed the Fire Protection Engineer to evaluate the appropriate compensatory measure. The compensatory measure for this instance was hourly fire watch. The licensee planned to repair and seal the deteriorating ceiling material and then remove the combustible material.

ATTACHMENT:

SUPPLEMENTAL INFORMATION

KEY POINTS OF CONTACT

Licensee

P. Gardner, Director Site Operations

M. Lingenfelter, Engineering Director

M. Huting, Engineering Program Director

D. Bosnic, Business Director

M. Kelly, Performance Assessment Manager

P. Albers, Operations Manager

P. Kissinger, Regulatory Affairs Manager

S. OConnor, Regulatory Affairs Analyst

P. Young, Engineering Supervisor

P. Nordmeier, Fire Protection Engineer

C. Steffins, Fire Marshall

L. Schulze, Operations

J. Johnson, System Engineer

J. Oquist, Program Engineer

G. Sherwood, Program Engineer

J. Zimmerman, Program Engineer

B. Strabley, Senior Reactor Operator

Nuclear Regulatory Commission

P. Voss, Resident Inspector

LIST OF ITEMS

Opened/Closed

05000263/2014008-01 NCV Shorting Switch Modification Failed to ensure Drywell Spray Valves would not Spuriously Open.

(Section 1R05.6(b)(1))

05000263/2014008-02 NCV Both Redundant Safe Shutdown Trains of Nitrogen Bottles were Found Located In the Same Fire Area.

(Section 1R05.6(b)(2))

05000263/2014008-03 NCV Repairs Credited for Hot Shutdown Conditions.

(Section 1R05.9(b)(1))

Attachment