IR 05000325/2009012

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November 18, 2009

EA-09-121 Mr. Benjamin Vice President Carolina Power and Light Company Brunswick Steam Electric Plant P.O. Box 10429 Southport, NC 28461

SUBJECT: BRUNSWICK STEAM ELECTRIC PLANT- RESPONSE TO APPEAL OF FINAL SIGNIFICANCE DETERMINATION FOR A WHITE FINDING (NRC INSPECTION REPORT NO. 05000325/2009012 AND 05000324/2009012)

Dear Mr. Waldrep:

This refers to your letter dated October 13, 2009, in which you responded to the Nuclear Regulatory Commission's (NRC's) Final Significance Determination of a White Finding and Notice of Violation issued on September 14, 2009. The violation involved a failure to correctly designate termination points for linking control power to the emergency diesel generator lockout relay reset circuitry during the implementation of a design change. This resulted in the wiring for the control relays being installed such that the emergency diesel generators could not be operated locally as required by the Brunswick Safe Shutdown Analysis Report. The NRC characterized the significance of the violation as White (i.e., a finding with low to moderate increased importance to safety). In your letter, you outlined six areas of contention as the bases for your appeal which you stated met one of the appeal criteria in Inspection Manual Chapter (IMC) 0609, Attachment 2, "Process for Appealing NRC Characterization of Inspection Findings (SDP Appeal Process)."

Specifically, in each of these six areas, you cited one or both of the following criteria from section 3 of Attachment 2: a) the NRC staff's application of the significance determination process was inconsistent with the applicable significance determination process guidance or lacked justification; or b) the NRC staff did not consider actual (verifiable) hardware, procedures, guidance, or equipment configuration identified at the regulatory conference or in writing prior to the final significance determination. Using the appeal guidelines described in IMC 0609, Attachment 2, your appeal was reviewed to determine if it had sufficient merit to be forwarded to a formal appeal panel. Although not required by these guidelines, our response to your appeal was reviewed by NRC staff in the Office of Nuclear Reactor Regulation, knowledgeable of the significance determination process, who were not involved in the preliminary or final significance determination. We have concluded, in consultation with the NRC's Office of Nuclear Reactor Regulation, that none of the six appeal contentions you raised met the criteria for further review. The NRC's analysis of each of the six areas of contention in your appeal is enclosed.

CP&L 2 Please note that the conclusions in this letter specifically address the bases for your appeal of the significance of a violation issued on September 14, 2009. Our final significance determination and our review of your appeal were based on plant-specific fire scenarios and plant-specific equipment configurations. Therefore, the conclusions reached herein do not set generic precedence or establish generic guidance for performing fire probabilistic risk assessments in support of 10 CFR 50.48(c) for a licensee who wishes to amend its license to adopt National Fire Protection Association 805. Questions regarding the applicability of these conclusions to fire probabilistic risk assessments in support of 10 CFR 50.48(c) should be forwarded to the appropriate staff and management in the Office of Nuclear Reactor Regulation.

For administrative purposes, this letter is issued as a separate NRC Inspection Report No. 05000325/2009012, and 05000324/2009012. Should you have any questions regarding this letter, please contact Mr. Kriss Kennedy, Director, Division of Reactor Safety, at 404-562-4601.

Sincerely,/RA: Victor M. McCree for/ Luis A. Reyes Regional Administrator Docket No.: 50-325, 50-324 License No.: DPR-71, DPR-62

Enclosure:

Detail Appeal Analysis cc w/encl.: (See page 3) (*) - SEE PREVIOUS PAGE FOR CONCURRENCE XG PUBLICLY AVAILABLE G NON-PUBLICLY AVAILABLE G SENSITIVE xG NON-SENSITIVE ADAMS: xG Yes ACCESSION NUMBER:_________________________ xG SUNSI REVIEW COMPLETE OFFICE RII:DRS RII:DRS RII:DRS RII:DRP NRR RII:EICS RII:DRS SIGNATURE * * * * RA NAME R.Rodriguez G.MacDonald R. Nease R. Musser C. Evans K. Kennedy DATE 11/13/2009 11/13/2009 11/16/2009 11/17/2009 11/ /2009 11/ 18/2009 E-MAIL COPY? YES NO YES NO YES NO YES NO YES NO YES NO YES NO OFFICE RII:ORA SIGNATURE RA NAME V. McCree DATE 11/18/2009 E-MAIL COPY? YES NO YES NO YES NO YES NO YES NO YES NO YES NO OFFICIAL RECORD COPY DOCUMENT NAME: S:\DRS\ENG BRANCH 2\SERP-ESCALATED ENF\BRU EDG LOCK-OUT APPEAL\APPEAL RESPONSE LETTER-REV2.DOC CP&L 3 cc w/encl: R. J. Duncan, II Vice President Nuclear Operations Carolina Power & Light Company Electronic Mail Distribution Michael J. Annacone Director Site Operations Brunswick Steam Electric Plant Progress Energy Carolinas, Inc. Electronic Mail Distribution Edward L. Wills, Jr. Plant General Manager Brunswick Steam Electric Plant Progress Energy Carolinas, Inc.

Electronic Mail Distribution Benjamin Vice President Brunswick Steam Electric Plant Progress Energy Carolinas, Inc. Electronic Mail Distribution Christos Kamilaris Director Fleet Support Services Carolina Power & Light Company Electronic Mail Distribution Joseph W. Donahue Vice President Nuclear Oversight Carolina Power and Light Company Electronic Mail Distribution Brian C. McCabe Manager, Nuclear Regulatory Affairs Progress Energy Carolinas, Inc. Electronic Mail Distribution Phyllis N. Mentel Manager, Support Services Brunswick Steam Electric Plant Progress Energy Carolinas, Inc. Electronic Mail Distribution Michael S. Williams Manager, Training Brunswick Steam Electric Plant Progress Energy Carolinas, Inc.

Electronic Mail Distribution (Vacant) Manager License Renewal Progress Energy Electronic Mail Distribution Annette H. Pope Supervisor, Licensing/Regulatory Programs Brunswick Steam Electric Plant Progress Energy Carolinas, Inc.

Electronic Mail Distribution Senior Resident Inspector U.S. Nuclear Regulatory Commission Brunswick Steam Electric Plant U.S. NRC 8470 River Road, SE Southport, NC 28461 John H. O'Neill, Jr.

Shaw, Pittman, Potts & Trowbridge 2300 N. Street, NW Washington, DC 20037-1128 Peggy Force Assistant Attorney General State of North Carolina P.O. Box 629 Raleigh, NC 27602 Chairman North Carolina Utilities Commission Electronic Mail Distribution Robert P. Gruber Executive Director Public Staff - NCUC 4326 Mail Service Center Raleigh, NC 27699-4326 (cc w/encl cont'd - See page 4)

CP&L 4 (cc w/encl cont'd) Brunswick County Board of Commissioners P.O. Box 249 Bolivia, NC 28422 James Ross Nuclear Energy Institute Electronic Mail Distribution Public Service Commission State of South Carolina P.O. Box 11649 Columbia, SC 29211 W. Lee Cox, III (Acting) Section Chief Radiation Protection Section N.C. Department of Environmental Commerce & Natural Resources Electronic Mail Distribution Warren Lee Emergency Management Director New Hanover County Department of Emergency Management 230 Government Center Drive Suite 115 Wilmington, NC 28403 Enclosure Detailed Appeal Analysis Carolina Power & Light provided a detailed analysis for six areas of contention as the bases for their appeal which they stated met the appeal criteria in Inspection Manual Chapter (IMC) 0609, Attachment 2, "Process for Appealing NRC Characterization of Inspection Findings (SDP Appeal Process)." Specifically, in each of these six areas, CP&L cited one or both of the following two criteria in section 3 of IMC 0609, Attachment 2: a) the NRC staff's application of the significance determination process was inconsistent with the applicable significance determination process guidance or lacked justification; or b) the NRC staff did not consider actual (verifiable) hardware, procedures, guidance, or equipment configuration identified at the regulatory conference or in writing prior to the final significance determination In the licensee's detailed analysis, enclosed with the letter, these six areas of contention were associated with refinement areas. Below is NRC's review of each of the licensee's six areas of contention. Appeal Area #1/Licensee Refinement Area #1 - Fire Ignition Frequencies Licensee's assertion: A sensitivity evaluation of electrical cabinets and main control boards performed by CP&L staff, consistent with frequently asked question (FAQ) 08-0048 guidance was not considered by the NRC. The licensee stated that the NRC did not consider their sensitivity evaluation for determining ignition frequencies for electrical cabinets and main control boards in the final significance determination. The licensee stated that this meets criterion 3.b. of Inspection Manual Chapter (IMC) 0609, Attachment 2, as a basis for appeal. NRC's conclusion: This assertion does not meet appeal criterion 3.b, in that this criterion is based on plant hardware, procedures, or equipment configurations not being considered by the NRC. Criterion 3.b. does not include the failure to consider a sensitivity analysis in the significance determination process as a basis for appeal. However, the NRC reviewed the licensee's sensitivity evaluation, as initially performed, and determined it to be inadequate. Specifically, CP&L did not use plant-specific data in performing the sensitivity evaluation as directed by NUREG/CR-6850 and FAQ 08-0048. Therefore, the licensee's appeal in this appeal area does not merit further review. Basis for NRC's conclusion: As described in the final significance determination letter of September 14, 2009, the NRC accepted the use of revised fire ignition frequencies (FIFs) for fire probabilistic risk assessments (PRAs) with the following provision: the fire PRA must include a sensitivity evaluation of the risk and delta-risk results to evaluations performed using the current bin FIFs in NUREG/CR-6850. Specifically, NUREG/CR-6850 directs licensees performing a fire PRA to divide the FIFs by the number of ignition sources within a bin to obtain plant specific data. In lieu of obtaining plant specific data in this manner, CP&L developed a ratio of fire bin FIFs between NUREG/CR-6850 and EPRI 1016735, and then applied this ratio as a reduction to the IMC 0609, Appendix F, FIFs used by NRC. CP&L staff performed walk-downs to obtain plant-specific data; however, this was done after the NRC issued its final determination on September 14, 2009. Furthermore, the NRC concluded that incorporating the revised FIFs per FAQ 08-0048 would not change the final risk characterization.

2 Enclosure Appeal Area #2/Licensee Refinement Area #3- Source Applicability

Licensee's assertion: The NRC did not provide justification for considering high energy arcing fault (HEAF) fire scenarios for Common Substations C and D and Substations 1L and 2L. The licensee contended that electrical cabinets of Common Substations C and D and Substations 1L and 2L contain no mechanical connections and, therefore should not be counted as potential fire sources. The licensee stated that this meets criterion 3.a of IMC 0609, Attachment 2 as a basis for appeal.

NRC's conclusion: The NRC disagrees with the licensee's assertion that there was no justification for considering HEAF fire scenarios for Common Substations C & D, and Substations 1L and 2L. In the final significance determination, the NRC provided clear justification for the modeling assumptions used for Common Substations C and D, and Substations 1L and 2L which followed applicable guidance in IMC 0609, Appendix F. The licensee's appeal in this appeal area does not meet criterion 3.a.

The NRC recognized that the licensee could have asserted that actual internal configurations of Common Substations C and D end cabinets were not considered, which would be addressed by criterion 3.b. Pictures provided by the licensee subsequent to the regulatory conference showing mechanical connections were of adjacent cabinets, and were not appropriately labeled as such. Although provided in a timely manner, the licensee did not provide equipment configuration information adequate for NRC to consider in its significance determination. Therefore criterion 3.b was not met. The licensee's appeal in this appeal area does not meet either criterion 3.a or 3.b of IMC 0609, Attachment 2; therefore does not merit further review by an appeal panel.

Bases for NRC's conclusion: During the regulatory conference held on July 28, 2009, the licensee disagreed with the NRC's modeling of Common Substations C and D end cabinets as general electrical cabinets, and agreed to provide additional information regarding their internal configurations. Prior to the issuance of the final significance determination, the license provided numerous pictures of cabinet internals. The pictures were poorly labeled and the NRC assumed that the cabinet internals showing electrical terminations were those of Common Substations C and D end cabinets, which were the subject of discussion during the regulatory conference. Based on this, the NRC revised its final significance determination to model Common Substations C and D end cabinets as bus ducts, which was the closest fit per IMC 0609, Appendix F. As such, only HEAF fire scenarios were considered in the significance determination. The NRC justified this approach in the final significance determination through the use of applicable guidance in IMC 0609, Appendix F; therefore, appeal criterion 3.a was not met for Common Substation C and D. Upon receipt of this appeal, discussions with licensee staff, and further review of the photographs that CP&L staff provided, the NRC learned that the pictures showing electrical terminations were of adjacent transformer cabinets, not Common Substations C or D end cabinets. The NRC reviewed the licensee's appeal using criterion 3.b, and determined that it was not met, as the licensee did not provide adequate equipment configuration information for NRC to use in its final significance determination. Regardless of whether appeal criteria were met, the NRC performed a sensitivity analysis assuming Common Substations C and D end cabinets were not potential fire sources, and determined that the risk reduction was negligible and would not change the significance characterization of the violation.

3 Enclosure With respect to Substations 1L and 2L, during the regulatory conference held on July 28, 2009, the licensee disagreed with the NRC's modeling of Substations 1L and 2L end cabinets as general electrical cabinets, and agreed to provide additional information regarding their internal configurations. Prior to the issuance of the final significance determination, the license provided additional information showing that Substations 1L and 2L end cabinets contained disconnect switches. The NRC revised its significance evaluation to model Substations 1L and 2L end cabinets as breakers, which was the closest fit per IMC 0609, Appendix F. As such, both fire and HEAF scenarios were considered in the NRC's final significance determination. In their appeal, the licensee contended that the disconnect switches should not be considered as an ignition source. The characterization of Substations 1L and 2L end cabinets was justified in the final significance determination through the use of applicable SDP guidance. Therefore, appeal criterion 3.a was not met for Substations 1L and 2L. Appeal Area #3/Licensee Refinement Area #5 - Motor Control Center Fire Growth Rates Licensee's assertion: The motor control centers (MCCs) meet the guidance in NUREG/CR-6850 and FAQ 08-0042 to be considered "well-sealed." The licensee stated that the NRC did not provide justification for characterizing the MCCs as not being "well-sealed," which meets criterion 3.a of IMC 0609, Attachment 2, as a basis for appeal. NRC's conclusion: The licensee's assertion does not meet appeal criterion 3.a, in that the NRC's final significance determination evaluation was consistent with applicable guidance in NUREG/CR-6850 and IMC 0609, Appendix F, and was justified through the use of that guidance. These MCCs cannot be considered "well-sealed" due to the openings in the cabinets, as well as closing mechanisms on the cabinets which would allow an internal fire to propagate outside of its boundaries. The NRC also considered criterion 3.b in this appeal area, and concluded that it was not met, because actual MCC configurations were considered in the final risk determination. The licensee's basis for appeal does not meet either criterion 3.a, or criterion 3.b. Bases for NRC's conclusion: The licensee contends that the NRC did not provide adequate justification in treating the MCCs as not being "well-sealed," which they stated would meet appeal criterion 3.a of IMC 0609, Attachment 2. Further, the licensee stated that the NRC only considered weather-proof cabinets to be well-sealed. The NRC justified the characterization of the MCCs by applying the guidance in NUREG/CR-6850 and IMC 0609, Appendix F. Using this guidance, these MCCs cannot be considered "well-sealed" due to the openings in the MCCs, as well as the closing mechanisms on the cabinets which would allow an internal fire to propagate outside of its boundaries. The licensee also stated that only the upper half of the MCC sections should be considered for fires that could impact overhead cables. The NRC determined that it was not reasonable to assume that a fire within a closed cabinet could not propagate to other areas within the same cabinet. The NRC determined that postulated fires can grow, and therefore does not agree with the licensee's contention that only the upper half of MCC sections would be capable of affecting overhead cable trays. Subsequent to the regulatory conference, FAQ 08-0042 was issued. The NRC considered the MCC configurations relative to that FAQ, and determined that it was not applicable. The NRC justified the characterization of the MCCs in the final significance determination through the use of applicable SDP guidance; therefore appeal criterion 3.a was not met.

In reviewing this appeal area, the NRC also considered the applicability of criterion 3.b to IMC 0609, Attachment 2, which states that actual verifiable plant hardware or equipment configuration identified at the regulatory conference or prior to the issuance of the final significance determination was not considered by the NRC. Ultimately, the NRC determined 4 Enclosure that this criterion was not met, because actual MCC configurations were considered in the final significance determination. Appeal Area #4/Licensee Refinement Area #6 - Solid Bottom Trays Licensee Assertion: The NRC did not follow the guidance in NUREG/CR-6850 regarding cable damage delay for solid bottom cable trays, and did not provide justification in using a 5-minute time delay for damage to cables in solid bottom electrical cable trays. The licensee claimed this met criteria 3.a of IMC 0609, Attachment 2, as a basis for appeal.

NRC's conclusion: This assertion does not meet appeal criterion 3.a, in that the NRC applied the guidance in NUREG/CR-6850 and Sandia National Laboratory Report SAND 77, as appropriate, to the actual circumstances, which was fully justified in the final significance determination. Therefore, the licensee's appeal in this appeal area does not merit further review.

Bases for NRC's conclusion: Based on the guidance in NUREG/CR-6850, the NRC agreed that some cable damage time delay credit should be given for cables located in solid bottom trays. In the final significance determination, the NRC determined the appropriate cable damage time delay credit to be 5 minutes. It is the NRC's view that data from actual test fires documented NUREG/CR-6850 must be applied when it is appropriate (i.e., when the tested configuration is similar to the actual in-plant configuration being modeled). The NRC concluded that it was not reasonable to assume that IEEE-383 cables in solid bottom trays would never ignite in a postulated fire. As stated in the final significance determination, the NRC used NUREG/CR 6850, Sandia National Laboratory Report SAND77, and actual cable tray configuration to reach an informed assumption that there would be a 5-minute delay prior to cable damage.

In addition, the delay time for damage for solid bottom tray barriers was a risk modeling assumption in the SDP analysis, and the basis for limiting the credit to 5 minutes was discussed with the licensee's staff and addressed in the final significance determination letter. The NRC followed the relevant guidance and the assumptions in question represent a justified risk modeling assumption which is not appealable. Therefore, the licensee's assertion did not meet appeal criterion 3.a of IMC 0609, Attachment 2.

Appeal Area #5/Licensee Refinement Area #7 - Non-Suppression Probability Licensee Assertion: The licensee provided four areas of contention in appeal area #5: (a) the NRC staff did not consider the timeline for non-suppression probability provided by CP&L; (b) the NRC provided no justification for the 3-minute cable damage delay for coated, qualified cable; (c) the NRC did not discuss how the fire timeline and fire growth was determined and when the detection occurs; and (d) the NRC's timeline does not identify when the credit for solid bottom trays and flame retardant coating starts. The licensee stated that this meets criteria 3.a and 3.b. of IMC 0609, Attachment 2, as a basis for appeal.

NRC's conclusion: None of the four contentions described in this assertion meet appeal criteria 3.a or 3.b; therefore, the licensee's appeal in this appeal area does not merit further review. Contention (a): Failure to consider the licensee's timeline for non-suppression does not meet either appeal criteria 3.a or 3.b. With respect to criterion 3.a, the NRC followed appropriate guidance and justified the non-suppression probability. Regarding criterion 3.b, the NRC considered plant hardware and equipment configurations in developing the non-suppression probability. Furthermore, the NRC considered the licensee's timeline, but disagreed with it.

5 Enclosure Contention (b): The licensee's contention that the NRC did not provide justification for the 3-minute cable damage delay does not meet appeal criterion 3.a or 3.b. With respect to criterion 3.a, the NRC followed appropriate guidance and justified the 3-minute cable damage delay for coated, qualified cables using actual cable and cable tray configurations and fire test data in developing the 3-minute cable damage delay. Regarding criterion 3.b, the NRC considered actual plant hardware and equipment configurations to develop the 3-minute cable damage delay. Contention (c): The failure to discuss how the fire timeline and fire growth was determined and when the detection occurs does not meet appeal criterion 3.a or 3.b. With respect to criterion 3.a, the NRC developed the fire-growth timeline consistent with applicable guidance in accordance with IMC 0609, Appendix F, and provided a summary of the results in the final significance determination. Regarding criterion 3.b, the NRC considered plant hardware, equipment configurations (actual cable and cable tray configurations), and fire test data in developing the fire-growth timeline used in the final significance determination.

Contention (d): The failure to identify when credit for solid bottom trays and fire retardant coatings starts does not meet either criterion 3.a or 3.b. With respect to criterion 3.a, the NRC determined how much credit to give for cable coatings and solid bottom trays consistent with applicable guidance in IMC 0609, Appendix F. Regarding criterion 3.b, the NRC considered actual cable and cable tray configurations, and test data in determining how much credit to give for cable coatings and solid bottom trays in the final significance determination. Bases for NRC's conclusion Contention (a): The NRC considered the licensee's proposed timeline for non-suppression probability, but disagreed with it. With respect to criterion 3.a, the NRC followed appropriate guidance in IMC 0609, Appendix F and NUREG/CR-6850, and justified the methodology used in developing the non-suppression probability used in the final significance determination. The NRC used appropriate guidance to develop non-suppression probability; therefore, the licensee did not meet appeal criterion 3.a. Regarding criterion 3.b, the NRC considered actual plant hardware, procedures and equipment configurations (cable and cable tray configurations) in developing the non-suppression probability used in the final significance determination. The NRC used actual plant configuration to determine non-suppression probability; therefore, the licensee did not meet appeal criterion 3.b. The licensee's appeal in this area did not meet any of the appeal criteria listed in IMC 0609, Attachment 2.Furthermore, the failure to consider the licensee's timeline does not meet any of the appeal criteria listed in IMC 0609, Attachment 2. Contention (b): With respect to criterion 3.a, the NRC followed appropriate guidance and justified the 3-minute cable damage delay for coated, qualified cables using actual cable. Specifically, the NRC reviewed fire testing referenced by NUREG/CR-6850 applicable to these passive fire protection features and determined that the licensee did not appropriately characterize the test data in their evaluation. Limitations in the test data relative to the credit for solid bottom cable tray barriers is discussed above in appeal item #4 above. The NRC used appropriate guidance to determine cable damage delay; therefore, the licensee did not meet appeal criterion 3.a. Regarding criterion 3.b, the NRC considered actual cable and cable tray configurations, and fire test data referenced by NUREG/CR-6850 in developing the 3-minute cable damage delay used in the final significance determination. The NRC used actual plant configuration to determine cable damage delay; therefore, the licensee did not meet appeal criterion 3.b. The NRC concluded that solid bottom trays and cables sprayed with Flame-Master 71A or Flame-Master 77 flame retardant coatings will not prevent fire ignition, fire 6 Enclosure Growth, or cable damage, but will delay the onset of ignition, propagation and cable damage, allowing more time for fire brigade response. The licensee's appeal in this area did not meet any of the appeal criteria listed in IMC 0609, Attachment 2.

Contention (c): With respect to criterion 3.a, the NRC developed the fire-growth timeline consistent with applicable guidance in IMC 0609, Appendix F, and provided a summary of the results in the Phase 3 SDP and final significance determination. As stated in the final significance determination, the NRC used NUREG/CR 6850, IMC 0609, and actual plant configurations to determine how much credit should be given to fire retardant coatings and solid bottom trays in delaying cable ignition. The NRC developed the fire-growth timeline consistent with IMC 0609 Appendix F and NUREG 1805, "Fire Dynamics Tools," which is referenced in IMC 0609. Fire detection and suppression was used to develop non-suppression probability also in accordance with IMC Appendix F and NUREG 1805. The NRC used the fire-growth timeline and the non-suppression probability in calculating 17 different fire scenarios. The results were provided in Summary Table 2 (for the MCR) and Summary Table 3 (for the cable spreading room) in the final significance determination. The NRC performed a spreadsheet analyses to calculate time of detection for all scenarios with results <1 minute. In accordance with IMC 0609, Appendix F, the results were rounded up to 1 minute, and were used for calculating the probability of non-suppression. The NRC used appropriate guidance in developing the fire-growth timeline; therefore, the licensee's appeal in this area did not meet appeal criterion 3.a. Regarding criterion 3.b, the NRC used actual cable and cable tray configurations in developing the fire-growth timeline used in the final significance determination. The NRC used actual plant configuration in developing the fire-growth timeline; therefore, the licensee's appeal in this area did not meet appeal criterion 3.b. The licensee's appeal in this area did not meet any of the appeal criteria listed in IMC 0609, Attachment 2.

Contention (d): With respect to criterion 3.a, the NRC determined how much credit to give for cable coatings and solid bottom trays consistent with applicable guidance in IMC 0609, Appendix F. As discussed above in appeal area #4 and appeal area #5, contention (c), delay credit for solid bottom trays and fire retardant coatings was incorporated into the final significance determination as cable damage time delay. As stated in the final significance determination, the NRC used NUREG/CR 6850, IMC 0609, and actual plant configurations to determine how much cable damage delay credit should be given to fire retardant coatings and solid bottom trays. The NRC developed time-to-damage consistent with IMC 0609, Appendix F and NUREG 1805, "Fire Dynamics Tools," which is referenced in IMC 0609. The NRC used appropriate guidance in determining how much credit to give for cable coatings and solid bottom tray; therefore, the licensee's appeal in this area did not meet appeal criterion 3.a. Regarding criterion 3.b, the NRC considered actual cable and cable tray configurations, and test data in determining how much credit to give for cable coatings and solid bottom trays in the final significance determination. The NRC used actual plant configuration is determining how much credit to give for cable coatings and solid bottom trays; therefore, the licensee's appeal in this area did not meet appeal criterion 3.b. The licensee's appeal in this area did not meet any of the appeal criteria listed in IMC 0609, Attachment 2.

Appeal Area #6/Licensee Refinement Area #8 - Alternative Safe Shutdown (ASSD)

Implementation Licensee's assertion: The NRC staff did not consider simulator scenarios and operator interviews, nor was there a justification for why this information was not considered in determining the entry point into the ASSD procedure for fires in main control room (MCR) panel XU-2. The licensee stated that this met criteria 3.a and 3.b. of Inspection Manual Chapter 0609, Attachment 2, as a basis for appeal.

7 Enclosure NRC's conclusion: The licensee's appeal in this area does not meet criterion 3.a, or criterion 3.b; therefore, does not merit further review. Regarding criterion 3.a, the NRC followed applicable guidance and provided justification for the modeling assumptions used in determining the ASSD entry point for fires in the MCR. Furthermore, in accordance with criterion 3.a, issues involving the staff's modeling assumptions are not appealable. Regarding criterion 3.b, the NRC considered actual MCR panel configurations in developing modeling assumptions used to determine the entry point into the ASSD. Basis for NRC's conclusion: The NRC disagrees with the licensee's assertion that the NRC did not consider simulator scenarios and the operator interviews in it's determination of the alternative safe shutdown (ASSD) entry point. The NRC reviewed and considered the simulator scenarios and operator interviews, but had concerns regarding the use of this data, because of operators' knowledge of the issue prior to the interviews. This performance deficiency was known by the licensee's staff since the fall of 2008, and operators were well aware of the risk of implementing procedure 0-ASSD-02 in light of this violation.

As stated in the final significance determination, the NRC risk analysts used the following risk modeling assumption: "that 10% of fires would remain unsuppressed and grow to the point where enough ASSD equipment an/or instrumentation is damaged such that the senior control operator would choose to enter the ASSD procedures." Regarding criterion 3.a, the NRC followed applicable guidance and provided justification for the modeling assumptions used in determining the ASSD entry point for fires in the MCR. The NRC justified the assumptions used in the final significance determination through the use of applicable SDP guidance; therefore appeal criterion 3.a was not met. Furthermore, in accordance with criterion 3.a, issues involving the staff's modeling assumptions are not appealable. Regarding criterion 3.b, the NRC considered actual MCR panel configurations in developing modeling assumptions used to determine the entry point into the ASSD procedures. The 10% ASSD factor was developed based on a review of MCR panel configurations and potential spurious equipment actuation and instrument failure due to fire-damaged cables. This damage could affect both onsite and offsite power. Because the NRC used actual plant configurations in determining the entry point into ASSD procedures, appeal criterion 3.b was not met.

Although the likelihood is low, a fire in MCR panel XU-2 could damage normal offsite power feeder breaker controls to the emergency buses and breaker controls for emergency diesel generators, including MCR cross-tie breaker controls. The NRC concluded that this would meet the ASSD entry criteria. The NRC followed applicable NRC guidance and used actual plant equipment configurations in developing justified risk modeling assumptions. Furthermore risk assumptions are excluded from the appeal criteria. The licensee's appeal in this area did not meet any of the appeal criteria listed in IMC 0609, Attachment 2.

Letter to Benjamin from Luis A. Reyes dated

SUBJECT: BRUNSWICK STEAM ELECTRIC PLANT- RESPONSE TO APPEAL OF FINAL SIGNIFICANCE DETERMINATION FOR A WHITE FINDING (NRC INSPECTION REPORT NO. 05000325/2009012 AND 05000324/2009012), Distribution w/encl: C. Evans, RII EICS L. Slack, RII EICS OE Mail (email address if applicable) RIDSNRRDIRS PUBLIC R. Pascarelli, NRR (Regulatory Conferences Only) RidsNrrPMBrunswick Resource L. Wert, RII DRP J. Munday, RII DRP R. Musser, RII DRP K. Kennedy, RII DRS H. Christensen, RII DRS F. Brown, NRR M. Ashley, NRR M. Cunningham, NRR S. Weerakkody, NRR