ML093230261
ML093230261 | |
Person / Time | |
---|---|
Site: | Brunswick ![]() |
Issue date: | 11/18/2009 |
From: | Reyes L Region 2 Administrator |
To: | Waldrep B Carolina Power & Light Co |
References | |
EA-09-121, IR-09-012 | |
Download: ML093230261 (12) | |
See also: IR 05000324/2009012
Text
UNITED STATES
NUCLEAR REGULATORY COMMISSION
REGION II
SAM NUNN ATLANTA FEDERAL CENTER
61 FORSYTH STREET, SW, SUITE 23T85
ATLANTA, GEORGIA 30303-8931
November 18, 2009
Mr. Benjamin C. Waldrep
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 Commissions (NRCs) 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 staffs 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 NRCs Office of Nuclear Reactor Regulation, that none of the
six appeal contentions you raised met the criteria for further review. The NRCs analysis of
each of the six areas of contention in your appeal is enclosed.
_________________________ 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
CP&L 3
cc w/encl: Michael S. Williams
R. J. Duncan, II Manager, Training
Vice President Brunswick Steam Electric Plant
Nuclear Operations Progress Energy Carolinas, Inc.
Carolina Power & Light Company Electronic Mail Distribution
Electronic Mail Distribution
(Vacant)
Michael J. Annacone Manager
Director Site Operations License Renewal
Brunswick Steam Electric Plant Progress Energy
Progress Energy Carolinas, Inc. Electronic Mail Distribution
Electronic Mail Distribution
Annette H. Pope
Edward L. Wills, Jr. Supervisor, Licensing/Regulatory Programs
Plant General Manager Brunswick Steam Electric Plant
Brunswick Steam Electric Plant Progress Energy Carolinas, Inc.
Progress Energy Carolinas, Inc. Electronic Mail Distribution
Electronic Mail Distribution
Senior Resident Inspector
Benjamin C. Waldrep U.S. Nuclear Regulatory Commission
Vice President Brunswick Steam Electric Plant
Brunswick Steam Electric Plant U.S. NRC
Progress Energy Carolinas, Inc. 8470 River Road, SE
Electronic Mail Distribution Southport, NC 28461
Christos Kamilaris John H. O'Neill, Jr.
Director Shaw, Pittman, Potts & Trowbridge
Fleet Support Services 2300 N. Street, NW
Carolina Power & Light Company Washington, DC 20037-1128
Electronic Mail Distribution
Peggy Force
Joseph W. Donahue Assistant Attorney General
Vice President State of North Carolina
Nuclear Oversight P.O. Box 629
Carolina Power and Light Company Raleigh, NC 27602
Electronic Mail Distribution
Chairman
Brian C. McCabe North Carolina Utilities Commission
Manager, Nuclear Regulatory Affairs Electronic Mail Distribution
Progress Energy Carolinas, Inc.
Electronic Mail Distribution Robert P. Gruber
Executive Director
Phyllis N. Mentel Public Staff - NCUC
Manager, Support Services 4326 Mail Service Center
Brunswick Steam Electric Plant Raleigh, NC 27699-4326
Progress Energy Carolinas, Inc.
Electronic Mail Distribution
(cc w/encl contd - See page 4)
CP&L 4
(cc w/encl contd)
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
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 staffs 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 licensees detailed analysis, enclosed with the letter, these six areas of contention were
associated with refinement areas. Below is NRCs review of each of the licensees six areas of
contention.
Appeal Area #1/Licensee Refinement Area #1 - Fire Ignition Frequencies
Licensees 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.
NRCs 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
licensees 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 licensees appeal in this appeal
area does not merit further review.
Basis for NRCs 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.
Enclosure
2
Appeal Area #2/Licensee Refinement Area #3- Source Applicability
Licensees 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.
NRCs conclusion: The NRC disagrees with the licensees 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
licensees 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 licensees 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 NRCs conclusion: During the regulatory conference held on July 28, 2009, the
licensee disagreed with the NRCs 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 licensees 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.
Enclosure
3
With respect to Substations 1L and 2L, during the regulatory conference held on July 28, 2009,
the licensee disagreed with the NRCs 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 NRCs 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
Licensees 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.
NRCs conclusion: The licensees assertion does not meet appeal criterion 3.a, in that the
NRCs 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 licensees basis for appeal does not meet either criterion 3.a, or
criterion 3.b.
Bases for NRCs 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 licensees 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
Enclosure
4
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.
NRCs 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 licensees appeal in this appeal area does not merit further
review.
Bases for NRCs 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 NRCs 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 licensees 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 licensees 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 NRCs 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.
NRCs conclusion: None of the four contentions described in this assertion meet appeal criteria
3.a or 3.b; therefore, the licensees appeal in this appeal area does not merit further review.
Contention (a): Failure to consider the licensees 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 licensees timeline, but disagreed with it.
Enclosure
5
Contention (b): The licensees 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 NRCs conclusion
Contention (a): The NRC considered the licensees 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 licensees appeal in this area did not meet any
of the appeal criteria listed in IMC 0609, Attachment 2.Furthermore, the failure to consider the
licensees 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
Enclosure
6
Growth, or cable damage, but will delay the onset of ignition, propagation and cable damage,
allowing more time for fire brigade response. The licensees 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 licensees 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
licensees appeal in this area did not meet appeal criterion 3.b. The licensees 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 licensees 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 licensees appeal in this
area did not meet appeal criterion 3.b. The licensees 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
Licensees 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.
Enclosure
7
NRCs conclusion: The licensees 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 staffs 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 NRCs conclusion: The NRC disagrees with the licensees assertion that the NRC did
not consider simulator scenarios and the operator interviews in its 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 licensees 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 staffs 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 licensees appeal in this area did not
meet any of the appeal criteria listed in IMC 0609, Attachment 2.
Enclosure
Letter to Benjamin C. Waldrep 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