IR 05000483/2011008
ML11133A171 | |
Person / Time | |
---|---|
Site: | Callaway |
Issue date: | 05/13/2011 |
From: | Geoffrey Miller NRC/RGN-IV/DRP/RPB-B |
To: | Heflin A Union Electric Co |
References | |
IR-11-008 | |
Download: ML11133A171 (24) | |
Text
UNIT ED STAT ES NU C LE AR RE G UL AT O RY C O M M I S S I O N May 13, 2011
SUBJECT:
CALLAWAY PLANT - NRC TEMPORARY INSTRUCTION 2515/183 INSPECTION REPORT 2011008
Dear Mr. Heflin:
On April 29, 2011, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your Callaway 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 May 4, 2011, with Mr. L. Graessle, Director, Operations Support, and other members of your staff.
The objective of this inspection was to assess the adequacy of actions taken at the Callaway Plant in response to the Fukushima Daiichi Nuclear Station fuel damage event. The results from this inspection, along with the results from similar inspections at other operating commercial nuclear plants in the United States, will be used to evaluate the United States nuclear industrys readiness to respond to a similar event. 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 a separate report. You are not required to respond to this letter.
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 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).
Union Electric Company -2-
Sincerely,
/RA/
Geoffrey B. Miller, Chief Project Branch B Division of Reactor Projects Docket No. 50-483 License No. NPF-30
Enclosure:
Inspection Report 2011008 w/Attachment: Supplemental Information
REGION IV==
Docket: 05000483 License: NPF-30 Report: 05000483/2011008 Licensee: Union Electric Company Facility: Callaway Plant Location: Junction Highway CC and Highway O Fulton, MO Dates: March 23 through April 29, 2011 Inspectors: D. Dumbacher, Senior Resident Inspector J. Groom, Resident Inspector L. Willoughby, Senior Project Engineer Approved By: Geoffrey B. Miller, Chief, Project Branch B Division of Reactor Projects-1- Enclosure
SUMMARY OF FINDINGS
IR 05000483/2011008, 03/23/2011 - 04/29/2011; Callaway Plant Temporary
Instruction 2515/183 - Followup to the Fukushima Daiichi Nuclear Station Fuel Damage Event.
This report covers an announced temporary instruction inspection. The inspection was conducted by resident and Region IV 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 temporary instruction is to be a high-level look at the industrys preparedness for events that may exceed the design basis for a plant. The focus of the temporary instruction was on
- (1) assessing the licensees capability to mitigate conditions that result from beyond design basis events, typically bounded by security threats;
- (2) assessing the licensees capability to mitigate station blackout conditions;
- (3) assessing the licensees capability to mitigate internal and external flooding events required by station design; and
- (4) assessing 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. If necessary, a more specific followup inspection will be performed at a later date.
INSPECTION RESULTS
The following table documents the NRC inspection at Callaway Plant, performed in accordance with Temporary Instruction 2515/183. The numbering system in the table corresponds to the inspection items in the temporary instruction.
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 and as required by Title 10 CFR 50.54(hh). Use Inspection Procedure 71111.05T, "Fire Protection (Triennial)," Section 02.03 and 03.03 as a guideline. If Inspection Procedure 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 The licensee performed inspections of equipment required to mitigate conditions that result from inspection that beyond design basis events. This equipment is committed to in licensing documents and severe equipment is available accident management guidelines. Walkdowns were performed on the Emergency Coordinator and functional. Active Supplement Guidelines, Severe Accident Management Guidelines and the Extensive Damage equipment shall be Mitigation Guidelines. The licensee performed reviews to ensure that the equipment called for in tested and passive these procedures was appropriately staged, the equipment was available and functional, and that equipment shall be the active equipment was tested satisfactory per plant procedures.
walked down and inspected. It is not expected that Describe inspector actions taken to confirm equipment readiness (e.g., observed a test, reviewed permanently installed test results, discussed actions, reviewed records, etc.).
equipment that is tested under an existing regulatory testing The inspectors performed inspection to verify that equipment required to mitigate conditions that program be retested.
result from beyond design basis events is available and functional. The equipment selected by the inspectors included permanently installed and alternative mitigating strategies intended to maintain This review should be or restore core cooling, containment, and spent fuel pool cooling capabilities under such done for a reasonable circumstances. Included in the inspectors' review were equipment specified in the following sample of mitigating procedures:
strategies/equipment.
SAG-1, Inject into the Steam Generators, Revision 5; SAG-3, Inject into the Reactor Coolant System, Revision 5;
SAG-7, Reduce Containment Hydrogen, Revision 3; Emergency Coordinator Supplemental Guideline, Attachment B, Filling Refueling Water Storage Tank from Firewater - Low Flow, Revision 8; Emergency Coordinator Supplemental Guideline, Attachment R, Starting Turbine-Driven Auxiliary Feedwater Pump on Loss of AC and DC Power, Revision 8; and Emergency Coordinator Supplemental Guideline, Attachment KK, Filling the Spent Fuel Pool, Internal Strategy, Revision 8 The inspectors examined the material condition of the components and observed operating parameters of equipment to verify that there were no obvious deficiencies. The inspectors also verified that the licensee had properly identified and resolved equipment problems that could impact the capability of mitigating systems and entered them into the corrective action program with the appropriate significance characterization.
Discuss general results including corrective actions by licensee.
The licensee identified one discrepancy in that the manifold and high pressure hose required for execution of SCG-2, "Depressurize the RCS," was not available on site. Despite this discrepancy, the licensee verified that the procedure could be completed by an alternate means. This issue was entered into the licensees corrective action program as Callaway Action Request 201102199. At the close of the inspection, the procedurally required hose and manifold had been ordered by the licensee.
The inspectors verified that the required equipment was available and functional.
Licensee Action Describe the licensees actions to verify that procedures are in place and can be executed (e.g.,
walkdowns, demonstrations, tests, etc.)
b. Verify through The licensee performed walkdowns to demonstrate that procedures to implement the strategies walkdowns or associated with B.5.b and 10 CFR 50.54(hh) are in place and executable. The scope of the demonstration that licensees reviews included those procedures specified in the Emergency Coordinator Supplement procedures to Guidelines. The procedures were reviewed to ensure that the applicable steps were adequately implement the specified and feasible.
strategies associated with B.5.b and 10 CFR 50.54(hh) are Describe inspector actions and the sample strategies reviewed. Assess whether procedures were in place and are in place and could be used as intended.
executable. Licensees may choose not to connect or operate The inspectors reviewed the licensees preparedness to handle large fires or explosions by permanently installed reviewing mitigating strategies. Additionally, the inspectors reviewed the adequacy and feasibility of equipment during this the licensees severe accident management guidelines. As part of their review, the inspectors verification.
verified that the necessary procedures are being maintained and are adequate, and that station personnel are knowledgeable and can implement the procedures. The inspectors verified that the This review should be procedures are feasible in light of the design of the equipment including any plant modifications.
done for a reasonable Samples selected by the inspectors were based on the complexity and risk significance of the sample of mitigating strategies. Specific strategies reviewed included the following:
strategies/equipment.
SAG-1, Inject into the Steam Generators, Revision 5; SAG-3, Inject into the Reactor Coolant System, Revision 5; SAG-7, Reduce Containment Hydrogen, Revision 3; SAG-8, Flood Containment, Revision 4; Emergency Coordinator Supplemental Guideline, Attachment B, Filling Refueling Water Storage Tank from Firewater - Low Flow, Revision 8; Emergency Coordinator Supplemental Guideline, Attachment R, Starting Turbine-Drive Auxiliary Feedwater Pump on Loss of AC and DC Power, Revision 8; and Emergency Coordinator Supplemental Guideline, Attachment X, Manually Depressurize Steam Generators, Revision 8.
Discuss general results including corrective actions by licensee.
The inspectors identified that B.5.b and 10 CFR 50.54(hh) procedures were in place and executable. The inspectors did note that the technical basis for using gravity drain of the refueling water storage tank to flood containment referenced in SAG-8 was not available. The licensee entered this discrepancy into their corrective action program as Callaway Action Request 201102691.
The licensee did identify several potential procedural enhancements. These potential enhancements were entered into the licensees corrective action program as Callaway Action Requests 201102191, 201102192, 201102193, 201102195, 201102200, 201102230, 201102267, and 201102198.
Licensee Action Describe the licensees actions and conclusions regarding training and qualifications of operators and support staff.
c. Verify the training and The licensee verified that the qualifications of personnel who implement strategies associated with qualifications of B.5.b and 10 CFR 50.54(hh) as well as severe accident management guidelines are current. The operators and the licensees review extended to operations, engineering, fire brigade team members, security officers support staff needed to and emergency response organization members.
implement the procedures and work instructions are current Describe inspector actions and the sample strategies reviewed to assess training and qualifications for activities related to of operators and support staff.
B.5.b and severe accident management guidelines as required The inspectors performed a sampling of training and qualifications records for licensee staff needed by 10 CFR 50.54 (hh).
to implement the procedures and work instructions related to B.5.b and 10 CFR 50.54(hh). The inspectors also reviewed training records associated with severe accident management guidelines.
Finally, the inspectors reviewed specific training modules to verify that the content of the material adequately described the mitigating strategy.
Discuss general results including corrective actions by licensee.
The inspectors verified that the licensee staff did receive qualification training associated with B.5.b and 10 CFR 50.54(hh) as well as severe accident management guidelines. The inspectors also verified that a continuing training program existed. The inspectors did not find any discrepancies during a review of individual training records.
Licensee Action Describe the licensees actions and conclusions regarding applicable agreements and contracts are in place.
d. Verify that any The licensee reviewed contracts with off-site support agencies (fire departments, hospitals, etc.)
applicable agreements and verified that the existing contracts are current and capable of being implemented.
and contracts are in place and are capable of meeting the For a sample of mitigating strategies involving contracts or agreements with offsite entities, describe conditions needed to inspector actions to confirm agreements and contracts are in place and current (e.g., confirm that mitigate the offsite fire assistance agreement is in place and current).
consequences of these events.
The inspectors performed a review of the contracts with off-site support agencies including local fire This review should be departments, local law enforcement, and local medical facilities. The inspectors review was done for a reasonable focused on ensuring that the contracts in place were current and capable of being implemented.
sample of mitigating strategies/equipment.
Discuss general results including corrective actions by licensee.
The inspectors verified that agreements and contracts associated with B.5.b and 10 CFR 50.54(hh)were in place and capable of being implemented.
Licensee Action Document the corrective action report number and briefly summarize problems noted by the licensee that have significant potential to prevent the success of any existing mitigating strategy.
e. Review any open Callaway Action Request 201102691, a tracking document for TI-183 issues, captured the following corrective action items resulting from both licensee and NRC inspector reviews:
documents to assess Installed emergency lighting is rated for only 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />; problems with mitigating strategy The plant process computers data acquisition equipment (multiplexers) had only one implementation nonsafety related power feed, a single point of vulnerability; identified by the licensee. Assess the Need for additional training was identified on how to manually operate auxiliary feedwater impact of the problem discharge flow control valves. A training request was generated to address familiarity with on the mitigating such equipment.
capability and the The inspectors assessed the impact of these corrective action items as enhancements that could remaining capability slightly increase the response capability of the operators during a B.5.b or 10 CFR 50.54(hh) event.
that is not impacted.
03.02 Assess the licensees capability to mitigate station blackout conditions, as required by 10 CFR 50.63, "Loss of All Alternating Current Power," and station design, is functional and valid. Refer to Temporary Instruction 2515/120, "Inspection of Implementation of Station Blackout Rule Multi-Plant Action Item A-22," as a guideline. It is not intended that Temporary Instruction 2515/120 be completely reinspected. The inspection should include, but not be limited to, an assessment of any licensee actions to:
Licensee Action Describe the licensees actions to verify the adequacy of equipment needed to mitigate a station blackout event.
a. Verify through The licensee verified the capability of equipment to mitigate station blackout conditions is functional, walkdowns and properly tested, and maintained. The licensees walkdowns focused on permanently staged inspection that all equipment specified in emergency operating procedures involving a complete loss of AC power.
required materials are Describe inspector actions to verify equipment is available and useable.
adequate and properly staged, tested, and maintained.
The inspectors performed inspection to verify that equipment required to mitigate station blackout conditions is available and functional. The equipment selected by the inspectors included permanently installed and staged equipment required by 10 CFR 50.63 and described in the licensee Updated Final Safety Analysis Report. Additionally, the inspectors reviewed supplemental electrical equipment that could function to terminate a station blackout condition. Specific systems reviewed by the inspectors include:
Turbine-driven auxiliary feedwater system; Condensate storage and transfer system; DC electrical distribution system; and Alternate emergency power supply diesel system The inspectors examined the material condition of the components and observed operating parameters of equipment to verify that there were no obvious deficiencies. The inspectors also verified that the licensee had properly identified and resolved equipment problems that could impact the capability of mitigating systems and entered them into the corrective action program with the appropriate significance characterization.
Discuss general results including corrective actions by licensee.
The inspectors verified that all required materials and equipment required to mitigate a station blackout condition were properly staged, tested, and maintained.
Licensee Action Describe the licensees actions to verify the capability to mitigate a station blackout event.
b. Demonstrate through The licensee performed a walkdown of procedures for response needed to respond to a station walkdowns that blackout event to ensure the procedures are executable. The procedures were reviewed to ensure procedures for that the applicable steps were adequately specified and feasible. Included in the licensees review
response to a station were verifications that components were adequately labeled and accessible, operators were blackout are knowledgeable and could execute the procedure and that the procedural steps served to execute executable.
the mitigating strategy.
Describe inspector actions to assess whether procedures were in place and could be used as intended.
The inspectors reviewed the licensees preparedness to mitigate a station blackout condition. As part of their review, the inspectors walked through the procedure to ensure they were feasible and technically accurate. A review of supporting calculations was performed for select procedures.
Individual procedure samples were selected by the inspectors based on the complexity and risk significance.
Additionally, the inspectors observed the licensee conduct a routine licensee emergency drill involving a station blackout situation on March 30, 2011, to identify any weaknesses and deficiencies in classification, notification, and protective action recommendation development activities. The inspectors observed emergency response operations in the Technical Support Center to determine whether the event classification, notifications, and protective action recommendations were performed in accordance with procedures. The inspectors also attended the licensee drill critique to compare any inspector-observed weakness with those identified by the licensee staff in order to evaluate the critique and to verify whether the licensee staff was properly identifying weaknesses and entering them into the corrective action program. As part of the inspection, the inspectors reviewed the drill package and other documents listed in the attachment.
Discuss general results including corrective actions by licensee.
The inspectors verified that the procedures needed to respond to a station blackout event are technically accurate, executable and up to date. Additionally, the inspectors verified that station personnel are knowledgeable and can implement the procedures.
03.03 Assess the licensees capability to mitigate internal and external flooding events required by station design. Refer to Inspection Procedure 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.
Licensee Action Describe the licensees actions to verify the capability to mitigate existing design basis flooding events.
a. Verify through The licensee performed walkdowns and inspections that all required materials and equipment walkdowns and necessary to mitigate the effects of internal or external flowing are adequate and properly staged.
inspection that all These walkdowns and inspections included verification that accessible doors, barriers, and required materials are penetration seals are functional. Additionally, the licensee performed calculation reviews to ensure adequate and properly that the potential sources of internal and external flooding were properly identified and that the plant staged, tested, and design was adequate to protect critical components from flooding.
maintained.
Describe inspector actions to verify equipment is available and useable. Assess whether procedures were in place and could be used as intended.
For internal flooding, the inspectors reviewed the Final Safety Analysis Report, the flooding analysis, and plant procedures to assess susceptibilities involving internal flooding. As part of their review, the inspectors reviewed the corrective action program to determine if licensee personnel identified and corrected flooding problems. Specific areas were walked down to verify that operator actions for coping with flooding can reasonably achieve the desired outcomes. The inspectors also inspected the areas listed below to verify the adequacy of equipment seals located below the flood line, floor and wall penetration seals, watertight door seals, common drain lines and sumps, sump pumps, level alarms, and control circuits, and temporary or removable flood barriers. Specific areas reviewed by the inspectors included:
Room 3101, Essential service water pipe chase;
Rooms 5201 and 5203, Emergency diesel generator rooms; and Room 1310, Residual heat removal heat exchanger room train A.
Additionally, the inspectors reviewed the Final Safety Analysis Report and related flood analysis documents to identify those areas that could reasonably be affected by external flooding. Due to the design and geographic location of Callaway, the only credible external flooding event is one caused by heavy rains. The inspectors reviewed the design of structures, systems and components and their ability to cope with a maximum precipitation event. The review included a walkdown of building roofs to ensure that drain paths were available and that the drain system has adequate protection (screens/covers) to prevent debris from disabling the system.
Discuss general results including corrective actions by licensee.
Generally all required materials for mitigating flooding events were adequate and properly maintained. Callaway flooding analysis documents do not rely on or assume available any flood removal equipment.
The licensee identified that the fuel building roof drains do not have a recurring preventative maintenance task to verify they are free of debris. Upon discovery, the licensee inspected the roof drains and found them to be functional. A preventive maintenance task to inspect the drains every three months was implemented consistent with the other drains on safety related buildings. This issue was entered into the licensees corrective action program as Callaway Action Request 201102411. The licensee also identified several degraded penetration seals as well as several seals with no preventative maintenance task to verify their condition. These issues were entered into the licensees corrective action program as Callaway Action Requests 200906746 and 201102735.
The inspectors noted that the licensee relies on sump annunciator response procedures which predominately result in directing an operator to investigate the cause of the high sump level. These annunciator procedures do not provide detailed guidance on how to isolate breaks in piping systems or where flood removal pumps are located.
The inspectors noted that the potential source of flooding identified for Rooms 5201 and 5203, emergency diesel generator rooms, was nonconservative in that it:
Used a pressure lower than the system design pressure for the postulated break in the essential service water system.
Credited installed sump pumps when a credible single source of power loss would have affected both pumps. A reanalysis confirmed that the resulting flood height with no sump pumps was acceptable.
These issues were entered into the corrective action program as Callaway Action Request 201102691.
The inspectors also identified that the licensee had not updated the internal flooding analysis for Room 3101, essential service water pipe chase, following a planned modification to the essential service water supply and return headers. Specifically, the licensees installation of high density polyethylene piping created a potential flooding source in excess of that currently analyzed in the Callaway licensing basis. This issue was entered into the licensees corrective action program as Callaway Action Request 201102957. The inspectors plan to conduct further inspection on this item; the results of the inspection will be documented in the second quarter resident inspection report.
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 Inspection Procedure 71111.21, "Component Design Basis Inspection," Appendix 3, "Component Walkdown Considerations," as a guideline to assess the thoroughness of the licensees walkdowns and inspections.
Licensee Action Describe the licensees actions to assess the potential impact of seismic events on the availability of equipment used in fire and flooding mitigation strategies.
a. Verify through The licensee performed walkdowns and inspections of installed fire and flood mitigation response walkdowns that all equipment. This included fire water storage tanks, water intake structures, fire pumps, piping and required materials are valves. The licensee reviews also included procedures for using alternative water sources and the adequate and properly portable diesel-driven fire pumper truck. The licensee reviews also included assessment of offsite staged, tested, and assistance and fire fighting communication methods since none of the permanently installed fire maintained.
response equipment is seismically designed or qualified.
Describe inspector actions to verify equipment is available and useable. Assess whether procedures were in place and could be used as intended.
The inspectors walked down the fire response materials, and verified they were adequate, properly staged, tested, and maintained with a qualified fire brigade leader. A multi-fire scenario due to a seismic event was discussed. This resulted in the need to use the developed licensee strategy to use the fire fighting pumper truck.
Discuss general results including corrective actions by licensee. Briefly summarize any new mitigating strategies identified by the licensee as a result of their reviews.
The inspectors concluded the licensee reviews of the fire water response systems were extensive and thorough. The inspectors concluded that mitigating fire equipment was mostly in place and adequately maintained.
The inspectors identified that since Callaway relies on operations personnel to make up the fire brigade, fighting more than one fire would initially be very difficult due to limited staffing. The licensee initiated Callaway Action Request 201103437 to evaluate staffing.
Additionally the inspectors identified that the licensee had not assessed the capability of the installed fire response equipment (halon) for the essential switchgear rooms. The licensee determined that this equipment does not need to be evaluated based on an industry frequently asked question. The licensee has trained its operators that if halon is not available to use a water source for electrical switchgear fires. The halon system is a threaded pipe system and is not seismically qualified. The introduction of fire fighting water into the switchgear room is not likely to
flood the room but could carry over an unanalyzed amount of water into the remaining essential switchgear room as the doors isolating the rooms were not flood doors. The licensee initiated Callaway Action Request 201103440 to evaluate the impact of the loss of the halon system.
Also, the scenario posed revealed that the fire pumper truck did not have sufficient lengths of suction hose to reach the alternate water sources specified in the licensee procedure. Additional suction hose was located elsewhere in a procedurally unspecified locker after the inspectors' question. The procedure required a strainer for the suction hose that was not on the truck.
Callaway Action Request 201103437 also addressed the truck equipment issues.
EXIT MEETING SUMMARY The inspectors presented the inspection results to Mr. L. Graessle, Director, Operations Support, and other members of licensee management at the conclusion of the inspection on May 4, 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
- F. Bianco, Assistant Operations Manager - Support
- R. Eickelman, Operations Supervisor
- L. Eitel, Supervising Engineer, Systems Engineering
- J. Fortman, Supervising Engineer, Major Projects
- S. Hogan, Assistant Manager, Protective Services - Emergency Preparedness
- S. Petzel, Engineer, Regulatory Affairs
- J. Picard, Licensed Reactor Operator
- N. Turner, Consulting Emergency Response Coordinator