IR 05000454/2011014

IR 05000454-11-014 & 05000455-11-014, on 03/23/2011 - 04/27/2011, Byron Station, Units 1 and 2, Temporary Instruction 2515/183 - Followup to the Fukushima Daiichi Nuclear Station Fuel Damage Event

ML111320288
Person / Time
Site:	Byron
Issue date:	05/13/2011
From:	Eric Duncan Region 3 Branch 3
To:	Pacilio M Exelon Nuclear, Exelon Generation Co
References
IR-11-014
Download: ML111320288 (21)

Text

May 13, 2011

SUBJECT:

BYRON STATION UNITS 1 AND 2 - NRC TEMPORARY INSTRUCTION 2515/183 INSPECTION REPORT 05000454/2011014; 05000455/2011014

Dear Mr. Pacilio:

On April 27, 2011, the U. S. Nuclear Regulatory Commission (NRC) completed an inspection at your Byron Station, Unit 1 and 2, using Temporary Instruction (TI) 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 27, 2011, with Mr. T. Tulon and other members of your staff.

The objective of this inspection was to promptly assess the capabilities of Byron Station, Unit 1 and 2, 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 a separate inspection 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 (PARS) component of the 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/

Eric R. Duncan, Chief Branch 3 Division of Reactor Projects Docket Nos. 50-454; 50-455 License Nos. NPF-37; NPF-66

Enclosure:

Inspection Report 05000454/2011014; 05000455/2011014 w/Attachment: Supplemental Information

REGION III==

Docket Nos: 50-454; 50-455 License Nos: NPF-37; NPF-66 Report No: 05000454/2011014; 05000455/2011014 Licensee: Exelon Generation Company, LLC Facility: Byron Station, Units 1 and 2 Location: Byron, IL Dates: March 23, 2011, through April 27, 2011 Inspectors: B. Bartlett, Senior Resident Inspector J. Robbins, Resident Inspector C. Thompson, IEMA Approved by: E. Duncan, Chief Branch 3 Division of Reactor Projects Enclosure

SUMMARY OF FINDINGS

IR 05000454/2011014; IR 05000455/2011014; 03/23/2011 - 04/27/2011; Byron Station, Units 1 and 2; 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 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 Temporary Instruction 2515/183, Followup to the Fukushima Daiichi Nuclear Station Fuel Damage Event, 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 a separate inspection 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 and 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 Licensee actions included the transport and testing of the portable pump that is utilized that equipment is available and within the applicable licensing basis. The pump was tested in accordance with a predefined functional. Active equipment preventative maintenance work instruction. In addition to the pump, the licensee performed shall be tested and passive hydrostatic testing of the fire hoses that would be utilized with this pump to ensure adequate equipment shall be walked down equipment performance. Permanently installed equipment such as diesel generators and and inspected. It is not emergency core cooling system (ECCS) pumps were not specifically tested as a result of expected that permanently this effort since this equipment was routinely tested and checked on daily operator rounds.

installed equipment that is tested under an existing The licensee performed an inventory inspection of equipment staged in the B.5.b pump regulatory testing program be warehouse in accordance with station procedures. Additionally, the licensee performed a retested.

walkdown within the plant for equipment utilized within the Severe Accident Management Guidelines (SAMGs). The licensee conducted this review to ensure that equipment used in This review should be done for a SAMG strategies was available and accessible for use.

reasonable sample of mitigating strategies/equipment.

The licensee reviewed the materials and equipment storage locations to determine if the specific locations provided adequate shelter from postulated security-related or natural phenomena events.

Describe inspector actions taken to confirm equipment readiness (e.g., observed a test, reviewed test results, discussed actions, reviewed records, etc.).

The inspectors reviewed the licensees assessment related to this area to ensure that the licensees review was consistent with the expectations provided in the operating experience.

Additionally, the inspectors reviewed the issues, and observations identified by the licensee and by the inspectors to ensure that they were entered into the corrective action program.

The inspectors conducted independent reviews and walkdowns to ensure that the B.5.b pump and ancillary equipment was available and capable for use consistent with the licensing basis. The inspectors performed a walkdown of the B.5.b equipment warehouse to ensure B.5.b equipment was properly staged and available. The inspectors verified that equipment utilized to transport the B.5.b pump was both available and capable.

Additionally, the inspectors conducted plant walkdowns for the station auxiliary feedwater, fire protection, and diesel generator systems to ensure that this equipment was accessible and available for use in implementing the stations SAMGs.

Discuss general results including corrective actions by licensee.

The inspectors observed that the licensee did not identify any unplanned challenges in implementing various B.5.b mitigating strategies. Some minor issues and improvement opportunities were identified both by the licensee and the inspector. Examples included:

• Miscellaneous B.5.b equipment was not labeled (IR 1193472); and

• The Work Control procedure did not have a specific coding to identify equipment that was related to B.5.b. Without this coding, equipment that was otherwise not important may not be repaired in a timely manner (IR 1195557).

The testing of the B.5.b pump was being treated as a preventative maintenance activity rather than a testing activity. As such, the structure of the acceptance criteria was embedded in the work instruction as compared to clearly identifiable acceptance criteria more commonly found in a surveillance activity. The inspectors did not identify a violation associated with these observations since the B.5.b pump was not safety-related or of augmented quality. Additionally, the licensee informed the inspectors that it was typical for the vendor to observe the annual pump performance test and that flow was monitored.

The licensee identified that the B.5.b pump warehouse was not seismically qualified, and was not required to be seismically qualified. The licensee entered this observation in the stations corrective action program (IR 1193472).

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 licensee reviewed the B.5.b strategies and applicable Severe Accident Management demonstration that procedures Strategies to ensure that the implementing procedures were available at their required to implement the strategies locations. The licensee performed system walkdowns of selected procedures to verify that associated with B.5.b and the equipment was accessible, adequately labeled, and that the procedure could be 10 CFR 50.54(hh) are in place executed as written.

and are executable. Licensees may choose not to connect or operate permanently installed Describe inspector actions and the sample strategies reviewed. Assess whether equipment during this procedures were in place and could be used as intended.

verification.

The inspectors reviewed the licensees assessment related to this area to ensure that the This review should be done for a licensees review was consistent with the expectations provided in the operating experience.

reasonable sample of mitigating Additionally, the inspectors reviewed the issues and observations identified by the licensee and by the inspectors to ensure that they were entered into the corrective action program.

strategies/equipment.

The inspectors independently verified that the procedures were available at a sample of the assumed locations and were the correction revision. The inspectors conducted independent walkdowns at the B.5.b building and within the station to verify that equipment utilized in the Extensive Damage Mitigation Guidelines (EDMGs) and SAMGs was available for use.

Discuss general results including corrective actions by licensee.

The licensee did not identify any issues. The inspectors did not identify any issues. A number of suggestions and enhancements were identified and entered into the corrective action program. These will be assessed by the licensee as part of the next phase of their review.

Describe the licensees actions and conclusions regarding training and qualifications Licensee Action of operators and support staff.

c. Verify the training and The licensees review included the identification of operator training and qualification qualifications of operators and requirements for the implementation of actions needed to mitigate B.5.b related events, the support staff needed to and for the implementation of the SAMGs. The licensee reviewed the stations learning implement the procedures and management training system records to verify that the required Maintenance first line work instructions are current for supervisors and Operations personnel met the B.5.b and SAMG training qualification activities related to Security requirements. In addition, the licensee identified the training qualification requirements for Order Section B.5.b and severe applicable emergency response organization (ERO) command and support staff for the accident management implementation of actions needed to mitigate a B.5.b related event, and for the guidelines as required by implementation of actions for the SAMGs. The licensee ensured that a sample of the ERO 10 CFR 50.54 (hh).

command and support staff training requirements were current.

Describe inspector actions and the sample strategies reviewed to assess training and qualifications of operators and support staff.

The inspectors reviewed the licensees assessment related to this area to ensure that the licensee review was consistent with the expectations provided in the operating experience.

The inspectors independently reviewed records from the stations learning management system and independently sampled a population of ERO command and support staff SAMG training records to ensure that the staffs training was up to date. Additionally, the inspectors reviewed a sample of the training material for SAMGs and B.5.b to understand the type of training that was provided.

Discuss general results including corrective actions by licensee.

The licensee did not identify any issues. The inspectors did not identify any issues.

Describe the licensees actions and conclusions regarding applicable agreements Licensee Action and contracts are in place.

d. Verify that any applicable The licensee conducted a review of the Byron B.5.b and severe accident management agreements and contracts are in strategies to identify any applicable off-site agreements and contracts necessary to support place and are capable of implementation. These contracts and agreements involved the local fire department, meeting the conditions needed hospitals, law enforcement, and diesel fuel oil vendor, as well as contracts with engineering to mitigate the consequences of vendors. Additionally, the licensee verified that these contracts were adequate to meet the these events.

intent for which they were comprised.

For a sample of mitigating strategies involving contracts or agreements with offsite This review should be done for a entities, describe inspector actions to confirm agreements and contracts are in place reasonable sample of mitigating and current (e.g., confirm that offsite fire assistance agreement is in place and strategies/equipment.

current).

The inspectors reviewed the licensees assessment related to this area to ensure that the licensees review was consistent with the expectations provided in the operating experience.

Additionally, the inspectors verified that issues, observations, and enhancements were entered into the stations corrective action program as appropriate.

The licensee did not identify any issues with the final review. The inspectors did not identify any issues with the off-site agreements from a current licensing basis perspective.

Discuss general results including corrective actions by licensee.

The licensee determined that the off-site contractual agreements would be adequate for events pertaining to B.5.b and applicable SAMGs.

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 Corrective Action Program issue report numbers are listed in the attachment to this report.

action documents to assess problems with mitigating The inspectors reviewed each of the IRs for potential impact to the licensees B.5.b strategy implementation mitigating strategies. Any findings and/or violations identified as a result of this inspection identified by the licensee.

will be documented in a separate inspection report.

Assess the impact of the problem on the mitigating capability and the remaining capability that is not impacted.

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 whether 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 re-inspected.

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 The licensee performed walkdowns and inspections of contingency and portable equipment inspection that all required relative to mitigating a station blackout event in accordance with the stations quarterly materials are adequate and surveillance procedure. Additionally, the licensee utilized the operator daily shift round properly staged, tested, and checks performed on the emergency power sources credited during a station blackout maintained.

event.

Describe inspector actions to verify equipment is available and useable.

The inspectors reviewed the licensees assessment related to this area to ensure that the licensees review was consistent with the expectations provided in the operating experience.

Additionally, the inspectors verified that issues, observations, and enhancements were entered into the stations corrective action program as appropriate.

The inspectors verified that a sample of equipment maintained in the stations quarterly surveillance checklist was available and properly staged. Additionally, the inspectors performed a walkdown of all the stations diesel generators to identify any apparent issues that could affect operability. The inspectors reviewed the licensees corrective action program for any known issues that could challenge the functionality of the equipment to ensure that the licensee had performed an adequate assessment and corrective actions were in place.

Discuss general results including corrective actions by licensee.

The licensee identified a number of minor issues and enhancement opportunities.

The inspectors determined that the issues identified by the licensee were minor in nature.

The inspectors identified one additional observation.

The inspectors observed that there was no direct indication of the stations spent fuel pool level or temperature in the main control room. The inspectors did not identify a regulatory issue with this observation. Additionally, the inspectors observed that the station did not calculate a spent fuel pool time to boil when the units were operating at power. In the case that spent fuel pool cooling was lost, the station had a bounding analysis for the onset of spent fuel pool boiling.

Licensee Action Describe the licensees actions to verify the capability to mitigate an SBO event.

b. Demonstrate through The licensee verified that implementing procedures for the station blackout strategies were walkdowns that procedures for up to date and available at their required locations. The licensee performed walkdowns of response to an SBO are these strategies to verify that areas were accessible, procedures could be executed, and executable.

equipment labeling was correct.

Describe inspector actions to assess whether procedures were in place and could be used as intended.

The inspectors reviewed the licensees assessment related to this area to ensure that the licensees review was consistent with the expectations provided in the operating experience.

Additionally, the inspectors verified that issues, observations, and enhancements were entered into the stations corrective action program as appropriate.

The inspectors reviewed a sample of the station procedures that would be utilized during a station blackout event. The inspectors conducted equipment walk downs of the diesel generators and auxiliary feedwater systems to identify any apparent issues or challenges in implementing the procedures. Additionally, the inspectors specifically reviewed the capability for the Units to share aspects of their auxiliary feedwater system through a common cross-tie piping connection.

Discuss general results including corrective actions by licensee.

The license identified a number of issues which were entered into the stations corrective action program. The inspectors reviewed these issues and did not identify any findings of significance.

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 licensee identified the flooding procedures that would be utilized for both internally and inspection that all required externally generated flooding events. These procedures were verified to be approved and materials are adequate and in place. The licensee performed walkdowns to verify that all equipment identified in plant properly staged, tested, and procedures conformed to the licensing requirements and was staged appropriately. Doors, maintained.

barriers, penetration seals, and curbs that were utilized for flooding mitigation were inspected to identify deficiencies and to ensure that they would provide a sufficient barrier.

Additionally, the licensee reviewed outstanding work orders and corrective action assignments to evaluate if any vulnerability existed. Identified issues were re-evaluated to ensure compliance with the current licensing basis or evaluated if the issue posed a beyond design basis risk to the plant.

Describe inspector actions to verify equipment is available and useable. Assess whether procedures were in place and could be used as intended.

The inspectors reviewed the licensees assessment related to this area to ensure that the licensees review was consistent with the expectations provided in the operating experience.

Additionally, the inspectors verified that issues, observations, and enhancements were entered into the stations corrective action program as appropriate.

With regard to external flooding, the inspectors review included checking for deviations from the descriptions provided in the Updated Final Safety Analysis Report (UFSAR) for features intended to mitigate the potential for flooding from external factors. The inspectors checked for obstructions that could prevent draining, checked that the roofs did not contain obvious loose items that could clog drains in the event of heavy precipitation, and determined whether barriers required to mitigate a flooding event were in place and operable.

Additionally, the inspectors performed a walkdown of the protected area to identify any modification to the site which would inhibit site drainage during a probable maximum precipitation event or allow water ingress past a barrier. The inspectors also reviewed the abnormal operating procedure for mitigating the design basis flood to ensure it could be implemented as written.

With regard to internal flooding, the inspectors reviewed selected risk-important plant design features and licensee procedures intended to protect the plant and its safety-related equipment from internal flooding events. The inspectors reviewed flooding analyses and design documents, including the UFSAR; engineering calculations; and abnormal operating procedures, to identify licensee commitments. In addition, the inspectors conducted plant system walkdowns to identify areas and equipment that may be affected by internal flooding caused by the failure or misalignment of nearby sources of water, such as the fire suppression or circulating water systems. The inspectors also reviewed the licensees corrective action documents with respect to past flood-related items to verify the adequacy of the corrective actions. The inspectors performed a walkdown of the essential service water system area to assess the adequacy of watertight doors and to verify that drains and sumps were clear of debris and were operable, and that the licensee complied with all commitments.

Discuss general results including corrective actions by licensee.

The licensee did not identify any regulatory issues, but did identify the following enhancements.

• The flood barrier surveillance procedure did not require that heavy floor plugs be removed periodically to check the condition of their seals. A concern with the condition of the plug seals had been previously identified by the NRC inspectors in the spring of 2007 and in response the licensee had enhanced their flood seal inspections to add a requirement that when a floor plug was removed that flood seal be inspected. Additional enhancements were being considered by the licensee (IR 1196756).

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 into 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 The licensee identified the applicable procedures that would be utilized to mitigate a fire and all required materials are or flood event to identify any potential that the equipments function could be lost during a adequate and properly staged, design basis seismic event at the station. The licensee performed walkdowns associated tested, and maintained.

with the storage of fire protection equipment, such as the stations fire brigade truck and trailer, carbon dioxide storage tanks, halon bottles, and the diesel generator fuel oil storage tanks foam suppression system. The licensee evaluated if the equipment and particular storage location was seismically qualified to ascertain if it would be reasonable to conclude if the equipment would be available for use during and following a design basis earthquake.

Describe inspector actions to verify equipment is available and useable. Assess whether procedures were in place and could be used as intended.

The inspectors reviewed the licensees assessment related to this area to ensure that the licensees review was consistent with the expectations provided in the operating experience.

Additionally, the inspectors verified that issues, observations, and enhancements were entered into the stations corrective action program as appropriate.

The inspectors independently reviewed the procedures that would be utilized during an earthquake, fire, and/or flooding event. The inspectors conducted multiple independent walkdowns and reviewed the documented assessment for the walkdowns conducted by the licensee. These walkdowns included, but were not limited to:

• B.5.b pump warehouse and ancillary equipment;

• Selected fire protection and suppression equipment in the auxiliary building;

• The diesel generator fuel oil storage tank rooms; and

• The main feedwater pump and condensate and condensate booster pump areas.

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 licensee did not identify any new mitigating strategies as a result of their review.

4OA6 Management Meetings

.1 Exit Meeting Summary

On April 27, 2011, the inspectors presented the inspection results to Mr. T. Tulon, 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.

ATTACHMENT:

SUPPLEMENTAL INFORMATION

KEY POINTS OF CONTACT

Licensee

T. Tulon, Site Vice President

B. Adams, Plant Manager

J. Feimster, Engineering

D. Gudger, Regulatory Assurance Manager

Nuclear Regulatory Commission

E. Duncan, Chief, Branch 3, Division of Reactor Projects

LIST OF ITEMS

OPENED

Opened

None

Closed

None

Discussed

None Enclosure