IR 05000263/2011009
ML111320400 | |
Person / Time | |
---|---|
Site: | Monticello ![]() |
Issue date: | 05/13/2011 |
From: | Kenneth Riemer NRC/RGN-III/DRP/B2 |
To: | O'Connor T Northern States Power Co |
References | |
IR-11-009 | |
Download: ML111320400 (24) | |
Text
May 13, 2011
SUBJECT:
MONTICELLO NUCLEAR GENERATING PLANT - NRC TEMPORARY INSTRUCTION 2515/183 INSPECTION REPORT 05000263/2011009
Dear Mr. OConnor:
On April 29, 2011, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your Monticello Nuclear Generating Plant, using Temporary Instruction 2515/183, Followup to the Fukushima Daiichi Nuclear Station Fuel Damage Event. The enclosed inspection report documents the inspection results which were discussed on April 26, 2011, with Mr. John Grubb and other members of your staff.
The objective of this inspection was to promptly assess the capabilities of Monticello Nuclear Generating Plant to respond to extraordinary consequences similar to those that have recently occurred at the Japanese Fukushima Daiichi Nuclear Station. The results from this inspection, along with the results from this inspection performed at other operating commercial nuclear plants in the United States, will be used to evaluate the U.S. nuclear industrys readiness to safely respond to similar events. These results will also help the NRC to determine if additional regulatory actions are warranted.
All of the potential issues and observations identified by this inspection are contained in this report. The NRCs Reactor Oversight Process will further evaluate any issues to determine if they are regulatory findings or violations. Any resulting findings or violations will be documented by the NRC in the next quarterly report. You are not required to respond to this letter.
T. O'Connor -2-In accordance with 10 CFR 2.390 of the NRCs Rules of Practice, a copy of this letter and its enclosure will be made available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of NRCs document system (ADAMS), accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).
Sincerely,
/RA/
Kenneth Riemer, Chief Branch 2 Division of Reactor Projects Docket No. 50-263 License No. DPR-22
Enclosure:
Inspection Report 05000263/2011009
REGION III==
Docket No: 50-263 License No: DRP-22 Report No: 05000263/2011009 Licensee: Northern States Power Company, Minnesota Facility: Monticello Nuclear Generating Plant Location: Monticello, Minnesota Dates: March 23 through April 29, 2011 Inspector: S. Thomas, Senior Resident Inspector Approved by: Kenneth Riemer Branch 2 Division of Reactor Projects Enclosure
SUMMARY OF FINDINGS
IR 05000263/2011009, 03/23/2011 - 04/29/2011; Monticello Nuclear Generating Plant
Temporary Instruction 2515/183 - Followup to the Fukushima Daiichi Nuclear Station Fuel Damage Event.
This report covers an announced Temporary Instruction (TI) inspection. The inspection was conducted by Resident and Region III inspectors. The NRCs program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649,
Reactor Oversight Process, Revision 4, dated December 2006.
INSPECTION SCOPE
The intent of the TI is to provide a broad overview of the industrys preparedness for events that may exceed the current design basis for a plant. The focus of the TI was on
- (1) assessing the licensees capability to mitigate consequences from large fires or explosions on site,
- (2) assessing the licensees capability to mitigate station blackout (SBO) conditions,
- (3) assessing the licensees capability to mitigate internal and external flooding events accounted for by the stations design, and
- (4) assessing the thoroughness of the licensees walk downs and inspections of important equipment needed to mitigate fire and flood events to identify the potential that the equipments function could be lost during seismic events possible for the site. If necessary, a more specific follow-up inspection will be performed at a later date.
INSPECTION RESULTS
All of the potential issues and observations identified by this inspection are contained in this report. The NRCs Reactor Oversight Process will further evaluate any issues to determine if they are regulatory findings or violations. Any resulting findings or violations will be documented by the NRC in the next quarterly report.
03.01 Assess the licensees capability to mitigate conditions that result from beyond design basis events, typically bounded by security threats, committed to as part of NRC Security Order Section B.5.b issued February 25, 2002, and severe accident management guidelines as required by Title 10 of the Code of Federal Regulations (10 CFR) 50.54 (hh). Use Inspection Procedure (IP) 71111.05T, Fire Protection (Triennial), Section 02.03 and 03.03 as a guideline. If IP 71111.05T was recently performed at the facility, the inspector should review the inspection results and findings to identify any other potential areas of inspection.
Particular emphasis should be placed on strategies related to the spent fuel pool. The inspection should include, but not be limited to, an assessment of any licensee actions to:
Licensee Action Describe what the licensee did to test or inspect equipment.
a. Verify through test or inspection The licensee performed walkdowns with qualified operators and discussions took place that equipment is available and regarding the use of the procedures and the desired result, as well as the required functional. Active equipment equipment. Equipment inventories were completed using approved site procedures with shall be tested and passive all gaps noted in the corrective action process. Monticello has the capability to mitigate equipment shall be walked down conditions that result from beyond basis events, typically bounded by security threats, and inspected. It is not committed to as part of B.5.b licensing process and using severe accident management expected that permanently guidelines. The flooding events require materials not currently onsite, but the procedure is installed equipment that is written assuming the flooding can be predicted allowing for the material to be obtained and tested under an existing barriers constructed.
regulatory testing program be retested.
The following procedures were performed to verify equipment was available and functional:
This review should be done for a
- 1488; Emergency Operating Procedures (EOP)/Abnormal Operating Procedures reasonable sample of mitigating (AOP) Equipment Inventory; strategies/equipment.
- 1224; Fire Brigade Equipment Inventory;
- OSP-FIR-0582; Portable Diesel Fire Pump Testing Procedure;
- ESP-125-0583; 125V DC Portable Battery Cart Testing Procedure; and
- IMP-1023; Fluke Model 87V EX Digital Multimeter Performance Test.
Procedure 1224 requires that the operator perform a condition inspection using criteria outlined in the procedure. Active equipment, such as the portable diesel fire pump and 125 VDC battery cart, were tested using approved site procedures. The 1488 procedure does not specifically require that an inspection be performed during the equipment inventory. Nonetheless, the inventory done for this activity did assess the condition and readiness of the equipment. All Emergency Operating Procedure (EOP) equipment was validated to be stored in the proper location.
Describe inspector actions taken to confirm equipment readiness (e.g., observed a test, reviewed test results, discussed actions, reviewed records, etc.).
The inspectors assessed the licensees capabilities by conducting a review of the licensees walkdown activities. In addition, the inspectors independently walked down and inspected a sampling of the major B.5.b contingency equipment staged throughout the plant.
Discuss general results including corrective actions by licensee.
During the EOP inventory, equipment was found to be stored in areas that could potentially be susceptible to damage during a seismic event. While performing the fire brigade inventory (1224), some equipment was not in the proper storage location, and some equipment called out in the B.5.b procedures was not on the inventory as expected.
Corrective actions were documented to correct these issues. The missing equipment from the B.5.b procedures is readily available at numerous locations onsite; however, a dedicated supply was not in the dedicated B.5.b storage location. Specific corrective action program (CAP) documents applicable to this section are listed in Section 3.01(e).
No issues of significance were identified by the inspectors.
Describe the licensees actions to verify that procedures are in place and can be Licensee Action executed (e.g., walkdowns, demonstrations, tests, etc.).
b. Verify through walkdowns or The A.7 - Severe Accident Mitigation Guidelines (SAMG) procedures are in-place and demonstration that procedures executable. This was demonstrated by a tabletop exercise using an Accident Management to implement the strategies Team (AMT) stationed in the Technical Support Center (TSC) with an operator in the control associated with B.5.b and room simulator to demonstrate the communication link. The tabletop exercise challenged 10 CFR 50.54
- (hh) are in-place all legs of the SAMGs. Activities to be performed in the plant were done by operations and are executable. Licensees personnel in a walk-through format with an evaluator observing their performance.
may choose not to connect or The AMT was able to complete priority actions that would have ensured event mitigation.
operate permanently installed The SAMGs refer to multiple EOP Support Procedures (C.5-3XXX) that are part of the equipment during this regular training cycle for the Operations crews. All actions performed by Operations verification.
during SAMG situations are in the EOP Support Procedures. Several of the A.8 (Extensive Damage Mitigation Strategy (EDMG) Overview) procedures that implement the This review should be done for a B.5.b program requirements are in-place and validated as executable via walkdowns.
reasonable sample of mitigating strategies/equipment.
Describe inspector actions and the sample strategies reviewed. Assess whether procedures were in place and could be used as intended.
The inspectors assessed the licensees capabilities by conducting a review of the licensees walkdown activities. In addition, the inspectors selected several sections of a sample of the procedures walked down by the licensee and walked them down to independently verify the licensees conclusions. The inspectors did not observe the performance of the tabletop exercise, but did review the exercise materials.
Discuss general results including corrective actions by licensee.
No gaps were identified that would impair the stations ability to utilize these mitigation strategies. Several enhancement opportunities were documented and entered in the licensees corrective action process. Specific CAP documents applicable to this section are listed in Section 3.01(e).
No issues of significance were identified by the inspectors.
Describe the licensees actions and conclusions regarding training and qualifications Licensee Action of operators and support staff.
c. Verify the training and The licensee conducted a review of their Emergency Plan (EP) Training Program, as well as qualifications of operators and a qualification search for the number of individuals qualified in each position, via the the support staff needed to Learning Management System (LMS) tool. The Training Department verified that all implement the procedures and positions in the six ERO duty teams were staffed by individuals qualified in their associated work instructions are current for jobs.
activities related to Security Order Section B.5.b and severe accident management Describe inspector actions and the sample strategies reviewed to assess training and guidelines as required by qualifications of operators and support staff 10 CFR 50.54 (hh).
The inspectors assessed the licensees training and qualification activities by conducting a review of training and qualification materials and records related to the current Emergency Response Organization (ERO) qualifications of the assigned site staff.
Discuss general results including corrective actions by licensee.
The training requirements, qualifications, and associated records needed to verify that the sites ERO could be staffed and function during an event, were reviewed by the licensee.
This recommendation is being met in accordance with site procedures and regulatory commitments. No deficiencies were noted when applicable training and qualification documents were reviewed. Specific CAP documents applicable to this section are listed in Section 3.01(e).
No issues of significance were identified by the inspectors.
Describe the licensees actions and conclusions regarding applicable agreements Licensee Action and contracts are in place.
d. Verify that any applicable The licensee performed a review of B.5.b and SAMG procedures to determine what agreements and contracts are in equipment is required from offsite venders to successfully implement their procedures.
place and are capable of The review was also expanded to include flooding and SBO concerns to consolidate the meeting the conditions needed scope and content of the agreements/contracts. The licensee conducted interviews of site to mitigate the consequences of program owners to determine what contracts were in place and what services, equipment, these events.
or materials offsite entities had agreed to provide.
This review should be done for a reasonable sample of mitigating For a sample of mitigating strategies involving contracts or agreements with offsite strategies/equipment.
entities, describe inspector actions to confirm agreements and contracts are in place and current (e.g., confirm that offsite fire assistance agreement is in place and current).
The inspectors assessed the licensees capabilities by conducting an independent review of the licensees letters of agreement, memorandums of understanding, and contracts for goods and services counted on to successfully implement their SAMGs and EDMGs.
The inspectors verified that each was current and whether or not each was adequate for meeting the licensees mitigation strategy.
Discuss general results including corrective actions by licensee.
Gaps were identified during the licensees review of offsite equipment that might be necessary to effectively implement their mitigating strategies. Corrective action documents have been initiated for the site to determine what equipment should be available onsite and what agreements are adequate for equipment that comes from offsite sources. At this time, the site has not made formal agreements to provide all equipment required from offsite entities. The licensee has determined that the agreements that are currently in place are sufficient to provide resources that the site might request in the event to allow for effective utilization of their mitigation strategies. Further review is required to determine what equipment should be purchased for onsite storage and what formal agreements should be made with offsite suppliers. Specific CAP documents applicable to this section are listed in Section 3.01(e).
No issues of significance were identified by the inspectors.
Document the corrective action report number and briefly summarize problems noted Licensee Action by the licensee that have significant potential to prevent the success of any existing mitigating strategy.
e. Review any open corrective The following entries into the licensees CAP were made to address issues identified during action documents to assess the evaluation of IER 11-1; Recommendation 1:
problems with mitigating strategy implementation
- CAP 1276416; IER 11-1 - During the 1224 Fire Equipment Inventory, Numerous capability that is not impacted.
Deficiencies were Found
- CAP 1276377; Abnormal Charger Indication during ESP-125-0583
- CAP 1276101; O2 Storage Rack not Anchored to the Wall
- CAP 1276087; IER 11-1 - Training Improvement on Use of SAMG/EDMG in Emergency Plan
- CAP 1276692; Not All Equipment Called for Use in A.8 Procedures (EDMGs) was Listed on the Fire Brigade Inventory
- CAP 1276414; N2 Tank Used to Support C.5-1301 (Alternate Rod Insertion) could be Damaged in a Seismic Event
- CAP 1276707; Offsite Support Equipment for A.8 not Assured Available
- CAP 1276715; Offsite Support Equipment for A.6 Procedure Not Assured Available
- CAP 1280539; Equipment Needed to Perform EDMGs not in Specified Location
The inspectors reviewed each condition report for potential impact to the licensees mitigation strategies. No significant impacts were identified.
03.02 Assess the licensees capability to mitigate station blackout (SBO) conditions, as required by 10 CFR 50.63, Loss of All Alternating Current Power, and station design is functional and valid. Refer to TI 2515/120, Inspection of Implementation of Station Blackout Rule Multi-Plant Action Item A-22, as a guideline. It is not intended that TI 2515/120 be completely reinspected.
The inspection should include, but not be limited to, an assessment of any licensee actions to:
Describe the licensees actions to verify the adequacy of equipment needed to Licensee Action mitigate an SBO event.
a. Verify through walkdowns and Abnormal Operating Procedure C.4-B.09.02A (Station Blackout) is the governing procedure inspection that all required for the plant response to a SBO. This procedure implements the few specific requirements materials are adequate and for mitigating the design basis SBO. This procedure also has steps which are not required properly staged, tested, and for design basis mitigation, but serve to increase the coping duration beyond the required maintained.
four hour period. The MNGP staff performed C.4-B.09.02A using the control room simulator combined with a plant walkdown to assure that all required materials and procedures are adequate, properly staged, and executable to support the design basis SBO mitigation.
Describe inspector actions to verify equipment is available and useable.
The inspectors assessed the licensees capability to mitigate SBO conditions by conducting a review of the licensees walkdown activities. In addition, the inspectors selected a sample of equipment utilized/required for mitigation of a SBO and conducted independent walkdowns of that equipment to verify that the equipment was properly aligned and staged.
Discuss general results including corrective actions by licensee.
Operators verified that the steps in this procedure that are required to meet the four hour coping duration are executable.
No issues of significance were identified by the inspectors.
Licensee Action Describe the licensees actions to verify the capability to mitigate an SBO event.
b. Demonstrate through Abnormal Operating Procedure C.4-B.09.02A (Station Blackout) is the governing procedure walkdowns that procedures for for the plant response to a SBO. This procedure implements the few specific requirements response to an SBO are for mitigating the design basis SBO. This procedure also has steps which are not required executable.
for design basis mitigation, but serve to increase the coping duration beyond the required four hour period. The MNGP staff performed C.4-B.09.02A using the control room simulator combined with a plant walkdown to assure that all required materials and procedures are adequate, properly staged, and executable to support the design basis SBO mitigation.
Describe inspector actions to assess whether procedures were in place and could be used as intended.
The inspectors assessed the licensees capabilities by conducting a review of the licensees walkdown activities. In addition, the inspectors selected several sections of a sample of the procedures walked down by the licensee and walked those down to independently verify the licensees conclusions.
Discuss general results including corrective actions by licensee.
Operation staff verified that the steps in this procedure that are required to meet the four hour coping duration are executable. Items that were identified by the licensee and entered into their CAP to address issues identified during the evaluation of IER 11-1, Recommendation 2, are listed in the List of Documents Reviewed at the end of this report.
No issues of significance were identified by the inspectors.
03.03 Assess the licensees capability to mitigate internal and external flooding events required by station design. Refer to IP 71111.01, Adverse Weather Protection, Section 02.04, Evaluate Readiness to Cope with External Flooding, as a guideline.
The inspection should include, but not be limited to, an assessment of any licensee actions to verify through walkdowns and inspections that all required materials and equipment are adequate and properly staged. These walkdowns and inspections shall include verification that accessible doors, barriers, and penetration seals are functional.
Describe the licensees actions to verify the capability to mitigate existing design Licensee Action basis flooding events.
a. Verify through walkdowns and The structures, systems, and components (SSCs) credited in MNGPs External Flooding, inspection that all required Internal Flooding, and High Energy Line Break (HELB) programs were cataloged.
materials are adequate and This catalogue list included all SSCs which control the movement of water between properly staged, tested, and adjacent volumes and the boundary penetrations between these adjacent volumes.
maintained.
Only the penetrations at or below maximum probable water levels based on station flooding calculations were evaluated.
Utilizing this list, field walkdowns were conducted to assess the condition of the flood control SSCs. For external flooding, a walkdown was performed to ensure pathways were clear and capable of performing their function (i.e., passage of water along the path assumed in the applicable calculation). The acceptability of the flood barriers and relief paths was documented on the list of the flood control SSCs.
Describe inspector actions to verify equipment is available and useable. Assess whether procedures were in place and could be used as intended.
The inspectors assessed the licensees capabilities to mitigate flooding by conducting a review of the licensees walkdown activities. Flood mitigation procedures were reviewed to verify usability. In addition, the inspectors conducted independent walkdowns of selected flood mitigation equipment to independently assess the licensees flood mitigation capabilities.
Discuss general results including corrective actions by licensee.
Of the 377 components to be inspected, 39 were not accessible. Monticello Nuclear Generating Plant is currently in a Refueling Outage (RFO). Currently during the refueling outage, work at the plant has required partial disassembly of credited barriers, created temporary openings through boundaries, restricted access to protected equipment, and obstructed viewing of some equipment by scaffold or other non-permanent tools and equipment staged for work. These items will be tracked as follow-on actions, with walkdowns to be conducted when station conditions permit. A walkdown was performed of the accessible plant areas having flood barriers and required relief paths. Walkdown notes documented the acceptability of every SSC and the cases where SSCs were inaccessible and could not be inspected. Items that were identified by the licensee and entered into their CAP to address issues identified during the evaluation of IER 11-1, Recommendation 3, are listed in the List of Documents Reviewed at the end of this report.
No issues of significance were identified by the inspectors.
03.04 Assess the thoroughness of the licensees walkdowns and inspections of important equipment needed to mitigate fire and flood events to identify the potential that the equipments function could be lost during seismic events possible for the site.
Assess the licensees development of any new mitigating strategies for identified vulnerabilities (e.g., entered it in to the corrective action program and any immediate actions taken). As a minimum, the licensee should have performed walkdowns and inspections of important equipment (permanent and temporary), such as storage tanks, plant water intake structures, and fire and flood response equipment, and developed mitigating strategies to cope with the loss of that important function. Use IP 71111.21, Component Design Basis Inspection, Appendix 3, Component Walkdown Considerations, as a guideline to assess the thoroughness of the licensees walkdowns and inspections.
Describe the licensees actions to assess the potential impact of seismic events on Licensee Action the availability of equipment used in fire and flooding mitigation strategies.
a. Verify through walkdowns that Important SSCs for fire protection were determined as equipment that can mitigate post all required materials are safe-shutdown earthquake (SSE) fires in the following four categories:
adequate and properly staged, tested, and maintained.
- permanently installed fire protection systems;
- permanently installed, seismically-qualified non-fire protection systems that could be used to fight fires;
- portable equipment that could be used to fight fires after an SSE; and
- offsite responders.
These categories of equipment, individually or in aggregate, must be capable of fighting fires in the critical portions of the station. Examples of critical portions of the station could include:
- control room and support structures;
- electrical switchgear rooms;
- turbine building;
- reactor building;
- diesel generator buildings;
- main and auxiliary transformers; and
- intake structures.
Piping and instrumentation diagrams were used to define the boundaries of the fire protection system within the scope of this recommendation, and the flood protection SSCs for this recommendation are the same as those used for Recommendation 3.
The licensee enlisted a contractor, who specializes in the evaluation of the impacts of seismic activity on structures, to perform walkdowns of specific areas onsite. Working from the lists of fire protection and flood protection SSCs provided by the licensee, this contractor performed a walkdown and examined all of the flood and fire mitigation SSCs which were identified, and assessed the seismic vulnerability of these SSCs as high, medium, or low.
A low vulnerability meant that the SSC would clearly withstand the SSE for the Monticello site. A medium vulnerability meant it was highly likely that the component would be shown through analysis to be able to survive the SSE for Monticello. A high vulnerability meant that it was quite possible that an SSE would disable the component.
Describe inspector actions to verify equipment is available and useable.
Assess whether procedures were in place and could be used as intended.
The inspectors conducted multiple walkdowns of important equipment needed to mitigate fire and flood events to identify the potential that the equipments function could be lost during or subsequent to a seismic event. Specific equipment reviewed as part of this assessment included a sampling of the major B.5.b contingency response equipment, installed fire protection and suppression equipment, installed diesel and electric fire pumps, and watertight hatches and floor plugs. In addition to the walkdowns, the inspectors reviewed a report prepared by the contractor which documented the results of how site flood and fire mitigation equipment would be impacted by an SSE.
Discuss general results including corrective actions by licensee. Briefly summarize any new mitigating strategies identified by the licensee as a result of their reviews.
For fire protection, the overall conclusion was that the system would likely suffer key failures in an SSE and could not be relied upon to be available after an earthquake. The mitigation strategy is to use B.5.b equipment to fight any fires that would occur following an earthquake. The B.5.b equipment is stored in a warehouse that is not designed as a Seismic Class I structure, but was examined by seismic experts and was it was concluded that it would remain intact following an SSE. Items that were identified by the licensee and entered into their CAP to address issues identified during the evaluation of IER 11-1, Recommendation 4, are listed in the List of Documents Reviewed at the end of this report.
No issues of significance were identified by the inspectors.
Meetings
.1 Exit Meeting
The inspectors presented the inspection results to Mr. Grubb, and other members of licensee management, at the conclusion of the inspection on April 26, 2011.
The inspectors asked the licensee whether any materials examined during the inspection should be considered proprietary. No proprietary information was identified.
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee
- T. OConnor, Site Vice President
- J. Grubb, Plant Manager
- W. Paulhardt, Assistant Plant Manager
- N. Haskell, Site Engineering Director
- K. Jepson, Business Support Manager
- S. Radebaugh, Maintenance Manager
- M. Holmes, Radiation Protection/Chemistry Manager
- S. Leonard, Regulatory Affairs Manager
- J. Earl, Emergency Preparedness Manager
Nuclear Regulatory Commission
- K. Riemer, Chief, Reactor Projects Branch 2
Enclosure