[Federal Register Volume 77, Number 31 (Wednesday, February 15, 2012)]
[Notices]
[Pages 8904-8926]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-3122]
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NUCLEAR REGULATORY COMMISSION
[NRC-2011-0278; Docket No.: 50-286]
Entergy Nuclear Indian Point 3, LLC.; Entergy Nuclear Operations,
Inc., Indian Point Nuclear Generating Unit 3; Exemption
1.0 Background
Entergy Nuclear Operations, Inc. (Entergy or the licensee) is the
holder of Facility Operating License No. DPR-64, which authorizes
operation of Indian Point Nuclear Generating Unit 3 (IP3). The license
provides, among other things, that the facility is subject to all
rules, regulations, and orders of the U.S. Nuclear Regulatory
Commission (NRC or the Commission) now or hereafter in effect.
IP3 is a pressurized-water reactor located approximately 24 miles
north of the New York City boundary line on the east bank of the Hudson
River in Westchester County, New York.
2.0 Request/Action
Title 10 of the Code of Federal Regulations (10 CFR) 50.48(b),
requires that nuclear power plants that were licensed to operate before
January 1, 1979, satisfy the requirements of 10 CFR part 50, Appendix
R, ``Fire Protection Program for Nuclear Power Facilities Operating
Prior to January 1, 1979,'' Section III.G, ``Fire protection of safe
shutdown capability.'' The circuit separation and protection
requirements being addressed in this request for exemption are
specified in Section III.G.2. Since IP3 was licensed to operate before
January 1, 1979, IP3 is required to meet Section III.G.2 of Appendix R
to 10 CFR part 50.
The underlying purpose of Section III.G of Appendix R to 10 CFR
part 50 is to establish reasonable assurance that safe shutdown (SSD)
of the reactor can be achieved and maintained in the event of a
postulated fire in any plant area. Circuits which could cause
maloperation or prevent operation of redundant trains of equipment
required to achieve and maintain hot shutdown conditions as a result of
fire in a single fire area must be protected in accordance with
III.G.2. If conformance with the technical requirements of III.G.2
cannot be assured in a specific fire area, an alternative or dedicated
shutdown capability must be provided in accordance with Section
III.G.3, or an exemption obtained in accordance with 10 CFR 50.12,
``Specific exemptions.''
By letter dated March 6, 2009, Entergy requested an exemption from
the requirements of 10 CFR part 50, Appendix R in accordance with 10
CFR 50.12. Specifically, Entergy requested an exemption to allow the
use of Operator Manual Actions (OMAs) in lieu of meeting certain
technical requirements of III.G.2 in Fire Areas AFW-6, ETN-4{1{time} ,
ETN-4{3{time} , PAB-2{3{time} , PAB-2{5{time} , TBL-5, and YARD-7. The
table below provides the dates and topics of the submittals related to
this request.
----------------------------------------------------------------------------------------------------------------
Subject Author Date Description ADAMS accession
----------------------------------------------------------------------------------------------------------------
Exemption Request from Appendix Entergy.......... March 6, 2009.... Original Submittal.... ML090760993
R.
Revised Exemption Request...... Entergy.......... October 1, 2009.. Revision to March ML092810230
2009, submittal,
incorporated changes
to Attachment 2,
Technical Basis in
Support of Exemption
Request.
Request for Additional NRC.............. January 20, 2010. Request for ML100150128
Information (RAI) 1. information on the
overall defense-in-
depth for each fire
zone.
RAI Response 1........ Entergy.......... May 4, 2010...... Response to the ML101320263
staff's January 20,
2010, RAI.
RAI 2................. NRC.............. August 11, 2010.. RAI on reactor coolant ML102180331
system makeup,
separation distances,
etc.
RAI Response 2........ Entergy.......... September 29, Response to the ML102930234
2010. staff's August 11,
2010, RAI.
RAI 3................. NRC.............. December 16, 2010 RAI on reactor coolant ML103500204
system makeup.
RAI Response 3........ Entergy.......... January 19, 2011. Responses to the ML110310242
staff's December 16,
2010, RAI.
Letter to revise previously Entergy.......... February 10, 2011 Letter updating tables ML110540322
submitted information. contained in previous
submittals.
Letter to revise previously Entergy.......... May 26, 2011..... Letter updating tables ML11158A196
submitted information. contained in previous
submittals.
----------------------------------------------------------------------------------------------------------------
[[Page 8905]]
III.G.2 establishes various protection options for providing
reasonable assurance that at least one train of systems, equipment and
cabling required to achieve and maintain hot shutdown conditions
remains free of fire damage. In lieu of providing one of the means
specified in the regulation, Entergy requests an exemption from III.G.2
to allow the use of OMAs to achieve and maintain hot shutdown
conditions in the event of fire in seven fire areas at IP3;
specifically, Fire Areas AFW-6, ETN-4{1{time} , ETN-4{3{time} , PAB-
2{3{time} , PAB-2{5{time} , TBL-5, and YARD-7.
3.0 Discussion
Pursuant to 10 CFR 50.12, the Commission may, upon application by
any interested person or upon its own initiative, grant exemptions from
the requirements of 10 CFR part 50 when: (1) The exemptions are
authorized by law, will not present an undue risk to public health or
safety, and are consistent with the common defense and security; and
(2) when special circumstances are present. The licensee stated that
special circumstances exist because the application of the regulation
in this particular circumstance is not necessary to achieve the
underlying purpose of the rule.
In accordance with 10 CFR 50.48(b), nuclear power plants licensed
to operate before January 1, 1979, are required to meet Section III.G,
of 10 CFR part 50, Appendix R. The underlying purpose of Section III.G
of 10 CFR part 50, Appendix R, is to ensure that the ability to achieve
and maintain SSD is preserved following a fire event. The regulation
intends for licensees to accomplish this by extending the concept of
defense-in-depth to:
Prevent fires from starting.
Rapidly detect, control, and extinguish promptly those
fires that do occur.
Provide protection for structures, systems, and components
important to safety so that a fire that is not promptly extinguished by
the fire suppression activities will not prevent the SSD of the plant.
III.G.2 requires one of the following means to ensure that a
redundant train of SSD cables and equipment is free of fire damage,
where redundant trains are located in the same fire area outside of
primary containment:
a. Separation of cables and equipment by a fire barrier having a 3-
hour rating;
b. Separation of cables and equipment by a horizontal distance of
more than 20 feet with no intervening combustibles or fire hazards and
with fire detectors and an automatic fire suppression system installed
in the fire area; or
c. Enclosure of cables and equipment of one redundant train in a
fire barrier having a 1-hour rating and with fire detectors and an
automatic fire suppression system installed in the fire area.
In its March 6, 2009, and October 1, 2009, submittals, Entergy
requested an exemption from certain technical requirements of III.G.2
to the extent that one of the redundant trains of systems necessary to
achieve and maintain hot shutdown is not maintained free of fire damage
in accordance with one of the required means prescribed in III.G.2 in
Fire Areas AFW-6, ETN-4{1{time} , ETN-4{3{time} , PAB-2{3{time} , PAB-
2{5{time} , TBL-5, and YARD-7.
Each OMA included in this review consists of a sequence of tasks
that occur in various fire areas. The OMAs are initiated upon
confirmation of a fire in a particular fire area, which the licensee
has further subdivided into fire zones. Listed in the order of the fire
area of fire origin, the OMAs included in this review are as follows:
----------------------------------------------------------------------------------------------------------------
Fire zone crediting
OMA No. Area of fire origin Area name the OMA Operator manual actions
----------------------------------------------------------------------------------------------------------------
1.................... AFW-6............... Auxiliary Feedwater 23.................. Locally start 33 AFW
(AFW) Pump Room. Pump via operation of
the Bus 6A circuit
breaker.
2.................... ETN-4{1{time} ...... Entrance to 7A.................. Swap 32 Component
Electrical Tunnels. Cooling Water (CCW)
pump to alternate power
supply or align city
water to charging
pumps.
3.................... 7A.................. Operate 480V Bus 3A
breaker locally to
start 31 AFW pump.
4.................... 7A.................. Locally operate the
bypass valve for Flow
Control Valve (FCV)-
1121 in support of use
of 31 AFW pump.
5.................... 60A................. Operate HCV-1118
manually to control 32
AFW pump.
6.................... 7A, 60A............. Align Appendix R Diesel
Generator (ARDG) to 480
V Buses 2A, 3A, 5A, and
312.
7.................... 7A, 60A............. Swap 31 or 32 charging
pump to alternate power
supply.
8.................... 7A, 60A............. Locally operate FCV-
405B, FCV-405D, or FCV-
406B to control AFW
flow to Steam
Generators (SGs).
9.................... 60A................. Locally open valve 227
to establish charging
[previously ``CVCS'']
makeup flowpath to
Reactor Coolant System
(RCS).
10................... 60A................. Locally close Level
Control Valve (LCV)-
112C and open valve 288
to align charging pump
suction to the
Refueling Water Storage
Tank (RWST).
11................... 60A................. Locally operate Pressure
Control Valve (PCV)-
1139 to ensure steam
supply to 32 AFW pump.
12................... 60A................. Locally operate PCV-
1310A and PCV-1310B to
ensure steam supply to
32 AFW pump.
13................... 60A................. Locally manually perform
Service Water (SW) pump
strainer backwash as
required.
14................... ETN-4{3{time} ...... Electrical Tunnel.. 73A................. Operate HCV-1118
manually to control 32
AFW pump.
15................... 73A................. Locally operate PCV-1139
to ensure steam supply
to 32 AFW pump.
16................... 73A................. Locally operate 32 PCV-
1310A, PCV-1310B to
ensure steam supply to
32 AFW pump.
17................... 73A................. Locally operate FCV-405C
and FCV-405D to control
AFW flow to SG.
18................... PAB-2{3{time} ...... Primary Auxiliary 6................... Locally close valve LCV-
Building; Charging 112C and open valve 228
Pump Rooms. to align charging pump
suction path to RWST.
[[Page 8906]]
19................... PAB-2{5{time} ...... Primary Auxiliary 17A, 19A, 58A....... Locally close supply
Building. breaker for 32 Charging
Pump [previously
``CVCS''] Pump.
20................... 17A, 19A, 58A....... Locally control 32
charging [previously
``CVCS''] pump using
scoop tube positioner.
21................... 59A................. Open bypass valve 227 to
establish charging
flowpath to RCS around
potentially failed
closed HCV-142.
22................... 17A, 20A, 27A, 30A.. Locally close LCV-112C
and open bypass valve
288 to establish
flowpath from RWST to
charging pump suction.
23................... TBL-5............... Turbine Building 52A................. Locally operate [bypass
and the AFW Pump valve for] FCV-1121 AFW
Building. pump recirculation
valve during pump
startup.
24................... 52A, 54A............ Locally operate FCV-406A
and FCV-406B to control
AFW flow to SGs.
25................... 37A, 38A, 43A, 44A.. Locally/manually
backwash SW pump
strainer as required if
power to strainer
associated with
selected SW pump is
lost (use one of STR
PMP-31 through STR PMP-
36).
26................... YARD-7.............. External Yard Areas 22.................. Locally start ARDG to
Intake Structure. supply Motor Control
Center (MCC) 312A in
support of the use of
SW pump 38.
27................... 22, 222............. Locally/manually
backwash SW Pump
strainer as required if
power to strainer
associated with
selected SW pump is
lost.
----------------------------------------------------------------------------------------------------------------
In their submittals, the licensee described elements of their fire
protection program that provide their justification that the concept of
defense-in-depth that is in place in the above fire areas is consistent
with that intended by the regulation. To accomplish this, the licensee
utilizes various protective measures to accomplish the concept of
defense-in-depth. Specifically, the licensee stated that the purpose of
their request was to credit the use of OMAs, in conjunction with other
defense-in-depth features, in lieu of the separation and protective
measures required by III.G.2 for a fire in the fire areas stated above.
In their March 6, 2009, and October 1, 2009, submittals, the
licensee provided an analysis that described how fire prevention is
addressed for each of the fire areas for which the OMAs may be required
because the separation requirements for equipment and electrical
circuits required by III.G.2 are not met. Specifically, the licensee
stated that noncombustible materials have been used to the maximum
extent practicable and that the introduction of combustible materials
into areas with safety-related equipment, including Fire Areas AFW-6,
ETN-4{1{time} , ETN-4{3{time} , PAB-2{3{time} , and PAB-2{5{time} is
strictly controlled by administrative procedures. The administrative
procedures govern the handling, storage, and limitations for use of
ordinary combustible materials, combustible and flammable gases and
liquids, and other combustible supplies. In addition, the licensee
stated that with the exception of Fire Areas TBL-5 and YARD-7, all of
the fire areas identified in the licensee's request are subject to the
Indian Point Energy Center Transient Combustible Control Program, as
implemented via procedure EN-DC-161, ``Control of Combustibles,'' and
are controlled as Level 2 combustible control areas. The licensee also
stated that Fire Area TBL-5, consisting of the Turbine Building and
certain adjacent fire zones, does not contain safety-related
structures, systems or components (SSCs) and is not subject to the
explicit transient combustible controls of EN-DC-161 but that procedure
OAP-017, ``Plant Surveillance and Operator Rounds'' includes inspection
guidelines for operator rounds, which include monitoring for general
area cleanliness, and for any housekeeping problems that may present a
fire or safety concern. Consequently, operator rounds performed each
shift provide for the monitoring of Area TBL-5 and other plant areas
for accumulations of combustibles that could present an unacceptable
fire safety challenge. Similarly, procedure ENMA-132, ``Housekeeping''
includes guidance for monitoring general area cleanliness as well as
monitoring for accumulations of combustibles. The licensee stated that
the administrative controls are described in the IP3 Fire Protection
Program (FPP), which is incorporated by reference into the Updated
Final Safety Analysis Report.
The licensee stated that both thermoplastic and thermoset low-
voltage power, control, and instrument cables are installed at IP3.
Since the thermoplastic insulated cables were manufactured and
installed prior to the issuance of IEEE-383, a standard for nuclear
plant cables, they were not qualified to that standard. In its May 4,
2010 letter, the licensee stated that the non-IEEE-383-qualified cables
are constructed with an asbestos glass braid outer jacket which
provides protection from flame spread. In addition, the licensee stated
that the results of various tests, as well as an actual fire event at
Indian Point Nuclear Generating Unit 2 (IP2) during plant construction,
have demonstrated the ability of this type of thermoplastic insulated
cables to minimize the growth and spread of cable fires. The licensee
also stated that the likelihood of self-ignited cable fires is
minimized by appropriately sized electrical protection devices (e.g.,
fuses and circuit breakers).
All of the fire areas in the plant are comprised of one or more
fire zones consisting of separate compartments or fire zone
delineations based on spatial separation. In addition, the licensee
stated that the localization of hazards and combustibles within each
fire zone, combined with the spatial or physical barrier separation
between zones, provides reasonable assurance that a fire that occurs
within a particular zone will be confined to that zone. As such, the
licensee provided a characterization of the defense-in-depth that is
present in each of the fire zones containing multiple trains of SSD
equipment. The licensee further stated that for each of the fire zones
where OMAs are performed, the adequacy of non-rated fire barriers was
evaluated to ensure that they can withstand the hazards associated with
the area. Therefore, this review evaluates the defense-in-depth
provided in each of the zones of concern.
In its submittals, the licensee provided a summary of plant-
specific fire protection features provided for each fire zone
identified in its request including an account of combustible
[[Page 8907]]
loading (both fixed and transient), ignition sources, detection,
suppression, administrative controls, and identified any additional
fire protection features that may be unique to the fire zone, such as
electrical raceway fire barriers. In its responses, the licensee stated
that combustibles and sources of ignition are tightly controlled by
administrative controls programs and that the areas included in this
exemption are not shop areas so hot work activities (such as welding)
are infrequent and appropriate administrative controls (e.g., hot work
permits, fire watch, and supervisory controls) are in place if hot work
activities do occur. The licensee also stated that the original
installation of the suppression and detection systems was accepted by
the NRC staff in safety evaluation reports (SERs) dated March 6, 1979,
and a supplement dated May 2, 1980, and that there are no code
compliance items that present an adverse impact to the implementation
of the requested OMAs. Within the fire zones of concern to its request,
the licensee stated that non-rated fire barrier assemblies are only
used or credited in Fire Area AFW-6 (Fire Zone 23), Fire Area ETN-4
(Fire Zones 7A and 60A), and Fire Area PAB-2 (Fire Zone 27A) and that
in each case, the fire resistive capability of the barrier was
evaluated and found to be acceptable given other features and
circumstances present in those zones.
Entergy stated that for each of the fire areas addressed in this
evaluation, Post-Fire Safe Shutdown (PFSSD) is principally accomplished
by remaining in the Central Control Room (CCR) and conducting a normal
(non-alternative) shutdown. In all cases, the identified OMAs mitigate
conditions where certain technical requirements of III.G.2 are not
satisfied.
Entergy further stated that the OMAs required for achieving and
maintaining hot shutdown conditions are feasible, reliable, and are not
impacted by environmental conditions (radiation, lighting, temperature,
humidity, smoke, toxic gas, noise, fire suppression discharge, etc.)
associated with fires in III.G.2 areas. The feasibility and reliability
of the requested OMAs is addressed in Section 4.0 of this evaluation.
NRC Staff Observations
In its May 4, 2010 response to RAI-07.1, the licensee stated that
no credit was taken for immediate and proactive OMA response by plant
operators upon the receipt of a fire detection alarm in any of the
identified fire zones. Instead, the licensee stated that OMAs are
initiated upon the detection of operating abnormalities or failures
caused by a postulated fire event. In this same response, the licensee
stated that they conducted exercises using the plant simulator to
evaluate the feasibility of the OMAs where a fire condition or a
spontaneous reactor trip caused by a fire was announced at the outset
of the simulation followed by the failure of discrete components that
are subject to impairment due to fire damage to cables or components
resulting from a fire in the area of concern. For fires originating in
fire zones lacking fire detection and/or automatic fire suppression
systems, the NRC staff considers it improbable that the operators would
properly indentify that the indications were the result of a fire
instead of some other fault. In addition, the operators would be
delayed in positively identifying the location of the fire based on
these indirect and ambiguous indicators. Therefore, for some scenarios
involving fire zones that lack fire detection systems, operators are
unlikely to identify and respond to a fire event in a manner that
prompts them to perform certain OMAs prior to a significant degradation
of the plant's condition. This becomes especially relevant for OMAs
that are required to be completed within a relatively short period of
time, e.g., within about 30 minutes, or have limited margins available
to complete the required actions.
For OMAs that are required to be completed within a short period of
time, the NRC staff evaluates if operators can reliably perform the
OMA. In order to be able to perform OMAs reliably, it is important that
operators are able to promptly implement any required action based on
clear indications. Indirect indicators and diagnostic analysis would
result in delayed action to initiate the appropriate OMAs and would
impair their reliable completion. For example, loss of control or
indication for a pump or other affected component could result from the
power supply circuit breaker opening due to an electrical fault other
than a fire, and the operator might delay taking actions for a fire
while investigating other potential and more-likely causes. The NRC
staff documented a position on procedures and training for such actions
in Section 4.2.9 of NUREG-1852, ``Demonstrating the Feasibility and
Reliability of Operator Manual Actions in Response to Fire,'' which
notes that the procedures for reactive actions should clearly describe
the indications which prompt initiation of the actions. Therefore,
where OMAs need to be performed within a short period of time, fire
zones crediting those OMAs are expected to have more robust defense-in-
depth and clear, direct procedures than fire zones that have a
significant margin in their OMA performance times.
In the August 11, 2010 RAI-02.1, and the December 16, 2010 RAI-
01.1, the NRC staff requested the licensee to describe the spatial
separation between redundant trains of equipment. However, the
licensee's response only provided information regarding the separation
between ignition sources and safe shutdown equipment and not
information regarding the separation between redundant trains of
equipment within the area. For example, in its response to RAI-01.1
dated January 19, 2011, the licensee stated that ``With respect to Item
3 above, Entergy has provided cable routing dimensional details for the
circuits of concern in the submittal dated September 29, 2010. However,
it should be noted that in most cases, the dimensional data provided
does not relate to the separation between redundant trains, but rather
the location and separation from ignition sources for a single train
that presents the potential for use of the credited OMA if that train
is impacted by fire damage.'' During a clarification call with the
licensee, the licensee did not provide any dimensional data on train
separation. Without dimensional data on train separation, the staff has
conservatively assumed that there is no discernable separation between
redundant trains of equipment.
In addition, the licensee noted that the introduction of
combustible materials into most areas included in its request was
limited via administrative procedures such as EN-DC-161. The licensee
stated that since Fire Area TBL-5 did not contain safety-related
systems or components, it was not addressed by this procedure. The NRC
staff notes that the licensee requested OMAs for Fire Area TBL-5 area
and that alternate shutdown equipment and several cables associated
with normal safe-shutdown equipment are located in this area. The
licensee stated that operator rounds are performed each shift in Fire
Area TBL-5 that would monitor the presence of combustibles that could
present an unacceptable fire safety challenge. In addition, the
licensee stated that procedures OAP-017 (Plant Surveillance and
Operator Rounds) and EN-MA-132 (Housekeeping) include guidance for
monitoring general area cleanliness including monitoring for
accumulations of combustibles. The NRC staff notes that the combustible
material controls procedures for this fire area are not as robust as
for safety-related areas, and therefore results in a reduction in the
[[Page 8908]]
defense-in-depth for the impacted fire zones.
Specific Area or Zone Discussion
Each of the fire areas or zones included in this exemption is
analyzed below with regard to how the concept of defense-in-depth is
achieved for each area or zone and the role of the OMAs in the overall
level of safety provided for each area or zone.
3.1 Fire Area AFW-6--Auxiliary Boiler Feed Pump Room, Elevation 18'-6''
of the Auxiliary Feed Pump Building (Fire Zone 23--Auxiliary Boiler
Feed Pump (ABFP) Room, Elevation 18'-6'')
3.1.1 Fire Prevention
Fire Area AFW-6 consists of a single room (the ABFP Room or the
Auxiliary Feedwater (AFW) Pump Room) and is designated as Fire Zone 23.
Note that the pumps which supply water to the steam generators
following a reactor trip are generically known as AFW pumps, but at IP3
they are also called Auxiliary Boiler Feed Pumps. The licensee stated
that the fire loading in this area is low and that fixed combustibles
consist of cable insulation, small quantities of lube oil, electrical
panels, and incident materials and Class A combustibles. The licensee
also stated that the ignition sources in the area consist of cable
runs, junction boxes, motors, pumps, and an electrical cabinet.
3.1.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 23 has an automatic, ionization
smoke detection system throughout the zone that is designed and
installed in accordance with National Fire Protection Association
(NFPA) standard NFPA 72E--1974 edition. The licensee also stated that
Fire Zone 23 has an automatic, wet-pipe fire suppression system
throughout the zone that is designed and installed in accordance with
NFPA 13--1983 Edition.
3.1.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 23 has a ceiling height of
approximately 13'-0'' and an approximate floor area of 1,254 square
feet. This fire zone contains the three AFW pumps (31, 32, and 33) and
their discharge valves used to supply water to the steam generators for
reactor coolant system decay heat removal when the normal feedwater
system is not available, such as following a reactor trip. As discussed
in Section 3.0 above, the licensee did not identify any separation
between credited and redundant trains of equipment.
3.1.4 OMAs Credited for a Fire in Fire Area AFW-6 (Fire Zone 23)
3.1.4.1 OMA 1--Locally Start 33 AFW Pump via Operation of the
Bus 6A Circuit Breaker
The licensee stated that cables AK3-PT2 and JB1-PT2/2 for the 33
AFW pump are located in Fire Zone 23 in rigid steel conduit located 6.3
to 12 feet above the floor and terminating in the AFW pump control
panel. In addition, the licensee stated that ignition sources in the
zone located less than 20 feet horizontally from cables AK3-PT2 and
JB1-PT2/2 consist of an electrical cabinet separated from the cable by
approximately 12.4 feet horizontally and that there are no intervening
combustibles.
The licensee also stated that cable JB1-X32/2, also for the 33 AFW
pump, is located in Fire Zone 23 in rigid steel conduit that runs
vertically from a junction box on the north wall for approximately 5.5
feet and then horizontally in a tray located approximately 10.8 ft
above the floor, before exiting the zone through the ceiling. In
addition, the licensee stated that ignition sources in the zone located
less than 20 feet horizontally from cable JB1-X32/2 consist of an AFW
pump motor and two electrical cabinets. According to the licensee, the
AFW pump motor is separated from the cable by approximately 8.2 feet
horizontally, one electrical cabinet is located approximately 5.7 feet
directly below the cable, and the other electrical cabinet is separated
from the cable by approximately 9.8 feet horizontally. The licensee
also stated that there are no intervening combustibles.
The licensee also stated that cables LL7-X32, LQ7-X32, and X32-Y2J,
also for the 33 AFW pump, are located in Fire Zone 23 in rigid steel
conduit that runs from flow transmitters FC-1136S and FC-1136A-S
located approximately 4.4 feet above the floor along the north wall
terminating at a junction box located approximately 5 feet above the
floor. In addition, the licensee stated that ignition sources in the
zone located less than 20 feet horizontally from cables LL7-X32, LQ7-
X32, and X32-Y2J consist of two AFW pump motors, which are separated
from the cables by approximately 7 feet horizontally and that there are
no intervening combustibles.
In the event that a fire occurs and a failure of the CCR control
switch response or pump indication prompts operator action to
investigate the breaker status at the switchgear, the licensee stated
that OMA 1 is available to restore this function by starting
the 33 AFW pump via local operation of the circuit breaker on Bus 6A,
which is located in a different fire area. If OMA 1 becomes
necessary, the licensee stated that they have assumed a 4.5 minute
diagnosis period and that the required time to perform the action is 13
minutes while the time available is 30 minutes, which provides 12.5
minutes of margin.
3.1.5 Conclusion for Fire Area AFW-6 (Fire Zone 23)
The NRC staff had previously issued an exemption from III.G.2 for
Fire Zone 23 in 1987 (ML003779008). In that exemption, the NRC staff
found that the low fire load, the fire detection system, the automatic
fire suppression system, and the distance between AFW pumps would
provide reasonable assurance that one train of shutdown equipment would
be available following a fire in this fire zone, including the use of
OMA 1. The NRC staff concludes that OMA 1 remains
acceptable for maintaining the reactor coolant system heat removal
function and that the III.G.2 exemption for Fire Zone 23 remains valid.
3.2 Fire Area ETN-4{1{time} --Electrical Tunnels (Fire Zone 7A--Lower
Electrical Tunnel, Elevation 33'-0'')
3.2.1 Fire Prevention
The licensee stated that the fire loading in this area is low and
that the fixed combustibles are cable insulation and incidental
materials, and that there are no transient combustibles. The licensee
also stated that the ignition sources in the area consist of cable
runs.
3.2.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 7A has an area-wide ionization
smoke detection system installed as well as thermal detection in the
cable trays and that the systems were designed and installed in
accordance with NFPA 72E, 1974 Edition. The licensee also stated that
Fire Zone 7A has a dry-pipe, preaction fire suppression sprinkler
system installed in the cable trays that was designed and installed in
accordance with NFPA 13, 1978 Edition and NFPA 15, 1977 Edition.
3.2.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 7A has a ceiling height of
approximately 16'-0'' and an approximate floor area of 6,386 square
feet. As discussed in Section 3.0 above, the licensee did not identify
any separation between credited and redundant trains of equipment.
[[Page 8909]]
3.2.4 OMAs Credited for a Fire in Fire Area ETN-4{1{time} (Fire Zone
7A)
3.2.4.1 OMA 2--Swap 32 Component Cooling Water (CCW) Pump To
Alternate Power Supply or Align City Water to Charging Pumps
The licensee stated that cable AS9-W1D for the 32 CCW pump is
routed through Fire Zone 7A. The licensee also stated that there are no
ignition sources, other than cables, located less than 20 feet
horizontally from the cables. The licensee further stated that the
postulated fire scenario would involve a transient combustible fire
that causes a failure of the power cables to redundant CCW pumps 31 and
33.
In the event that a fire occurs and causes a loss of the CCR
control or indication for all CCW pumps, the licensee stated that OMA
2 is available to restore this function by swapping the 32 CCW
pump to its alternate power supply or aligning city water to cool the
charging pumps. If OMA 2 becomes necessary, the licensee
stated that they have assumed failure at the onset of the fire and that
the required time to perform the action is 34 minutes while the time
available is >60 minutes, which provides 26 minutes of margin.
3.2.4.2 OMA 3--Operate 480V Bus 3A Breaker Locally To Start 31
AFW Pump
The licensee stated that cables A15-PT2, JB1 -PT2/1, JB1 -X32/1 for
the 31 AFW pump are all routed through Fire Zone 7A. The licensee also
stated that there are no ignition sources, other than cables, located
less than 20 feet horizontally from the cables. The licensee further
stated that the postulated fire scenario would involve a transient
combustible fire that causes a failure of cables serving the 31 AFW
pump.
In the event that a fire occurs and causes a loss of the CCR
control or indication for the 31 AFW pump, the licensee stated that OMA
3 is available to restore this function by operating a 480V
bus 3A breaker locally to start the 31 AFW pump. If OMA 3
becomes necessary, the licensee stated that they have assumed a 4.5
minute diagnosis period and that the required time to perform the
action is 7 minutes while the time available is 30 minutes, which
provides 18.5 minutes of margin.
3.2.4.3 OMA 4--Locally Operate FCV-1121 Bypass Valve in
Support of Use of 31 AFW Pump
The licensee stated that cables A15-PT2, JB1 -PT2/1, JB1 -X32/1 for
the 31 AFW pump, and cable JB1 -X32/1 for valve FCV-1121, which allows
recirculation flow for the 31 AFW pump, are all routed through Fire
Zone 7A. The licensee also stated that there are no ignition sources,
other than cables, located less than 20 feet horizontally from the
cables. The licensee further stated that the postulated fire scenario
would involve a transient combustible fire that causes a failure of
cables serving valve FCV-1121.
In the event that a fire occurs and causes a loss of the CCR
control or indication for all AFW pumps, the licensee stated that OMA
4 is available to restore recirculation flow by locally
operating the bypass valve for FCV-1121 to support the use of the 31
AFW pump. If OMA 4 becomes necessary, the licensee stated that
they have assumed a 4.5 minute diagnosis period and that the required
time to perform the action is 7 minutes while the time available is 30
minutes, which provides 18.5 minutes of margin.
3.2.4.4 OMA 6--Align Appendix R Diesel Generator (ARDG) to 480
V Buses 2A, 3A, 5A, and 312
The licensee stated that in the event of a loss of offsite power,
the use of the ARDG is credited for supplying power to the 480V buses
in the event of a fire in Fire Area ETN-4{1{time} . In the event that a
fire occurs and causes a loss of the CCR control or indication for the
buses, the licensee stated that OMA 6 is available to align
the ARDG to 480V buses 2A, 3A, 5A, and 312. If OMA 6 becomes
necessary, the licensee stated that they have assumed a loss of offsite
power at the outset of the event and that the required time to perform
the action is 50 minutes while the time available is 75 minutes, which
provides 25 minutes of margin. The NRC staff notes that this is
equivalent to implementing an alternate safe shutdown system in
accordance with III.G.3 and does not qualify for a III.G.2 exemption as
requested by the licensee.
3.2.4.5 OMA 7--Swap 31 or 32 Charging Pump To Alternate Power
Supply
The licensee stated that cables AH9-K1 B, AH9-PL2, and JA4-PL2/2
for the 32 charging pump are all routed through Fire Zone 7A. The
licensee also stated that there are no ignition sources, other than
cables, located less than 20 feet horizontally from the cables. The
licensee further stated that the postulated fire scenario would involve
a transient combustible fire that causes a failure of cables serving
charging pumps 31 and 32.
In the event that a fire occurs and causes a loss of the CCR
control or indication for all charging pumps, the licensee stated that
OMA 7 is available to restore this function by swapping the 31
or 32 charging pump to its alternate power supply. If OMA 7
becomes necessary, the licensee stated that they have assumed a 30-
minute diagnosis period and that the required time to perform the
action is 8 minutes while the time available is 75 minutes, which
provides 37 minutes of margin.
3.2.4.6 OMA 8--Locally Operate FCV-405B, FCV-405D, or FCV-406B
To Control AFW Flow to Steam Generators
The licensee stated that cables JB1-SX1/1, JF5-KV4, JF5-LL8, K45-
YM3, and K47-YM3 for valve FCV-406B, which controls the flow from the
32 AFW pump to the 34 steam generator (SG), are all routed through Fire
Zone 7A. The licensee also stated that there are no ignition sources,
other than cables, located less than 20 feet horizontally from the
cables. The licensee further stated that the postulated fire scenario
would involve a transient combustible fire that causes a failure of
cables serving the AFW pumps and valves.
In the event that a fire occurs and causes a loss of the CCR
control or indication for all AFW flow control valves, the licensee
stated that OMA 8 is available to restore this function by
locally operating FCV-405B, FCV-405D, or FCV-406B to control AFW flow
to the steam generators. If OMA 8 becomes necessary, the
licensee stated that they have assumed a 4.5-minute diagnosis period
and that the required time to perform the action is 17 minutes while
the time available is 30 minutes, which provides 8.5 minutes of margin.
3.2.5 Conclusion for Fire Area ETN-4{1{time} (Fire Zone 7A)
The NRC staff had previously issued exemptions for Fire Zone 7A in
1987 (ML003779008) and in 1984 (ML003779284). In those exemptions, the
NRC staff found that the fire detection system, the automatic fire
suppression system, and the distance between redundant trains would
provide reasonable assurance that one train of shutdown equipment would
be available following a fire in this fire zone. The NRC staff finds
the defense-in-depth features in this fire zone and the available time
margin would allow the use of OMAs 2, 3, 4, and 7. However,
based on new information in the current submittal the NRC staff finds
that OMA 6 is equivalent to implementing an alternate safe
shutdown system in accordance with III.G.3 and does not qualify for a
III.G.2 exemption as requested by the licensee.
[[Page 8910]]
Also, OMA 8 has insufficient available time margin to allow
for reliable performance considering the potential variables as
discussed in NUREG-1852. Therefore, the NRC staff finds that an
exemption from III.G.2 based on these OMAs cannot be granted for Fire
Zone 7A.
3.3 Fire Area ETN-4{1{time} --Electrical Tunnels (Fire Zone 60A--Upper
Electrical Tunnel, Elevation 43'-0'')
3.3.1 Fire Prevention
The licensee stated that the fire loading in this area is low and
that the fixed combustibles are cable and incidental materials and that
there are no transient combustibles. The licensee also stated that the
ignition sources in the area consist of cables.
3.3.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 60A has an area-wide, automatic
ionization smoke detection system installed that was designed and
installed in accordance with NFPA 72E, 1974 Edition. The licensee also
stated that Fire Zone 60A has a dry-pipe, preaction sprinkler fire
suppression system installed in the cable trays that was designed and
installed in accordance with NFPA 13, 1978 Edition and NFPA 15, 1977
Edition.
3.3.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 60A has a ceiling height of
approximately 10'-0'' and an approximate floor area of 3,200 square
feet. The licensee stated that cables and JB1-S99, JB1-X02, JB1-X02/1,
and JB1-SZ6 for valves PCV-1310A and PCV-1310B (steam supply to the 32
AFW pump), DE1-XV2 for 38 SW strainer, JB1-TA5 for valve HCV-1118
(governor valve for the 32 AFW pump), AQ3-K1C, AQ3-PL2, JA2-PL2/1 for
31 charging pump, JB1-KV6 for valve FCV-405B (32 AFW pump to 32 SG),
JB1-KV8 for valve FCV-405D (32 AFW pump to 34 SG), JB5-X1J for valve
HCV-142 (charging pump discharge to RCS loops), DD4-JB5 for valve LCV-
112C (volume control tank to charging pump suction), JB1-PT2/3 for
valve PCV-1139 (steam supply to the 32 AFW pump), JB1-SX1/1, JF5-KV4,
K45-YM3, K47-YM3, and JF5-LL8 for valve FCV-406B (31 AFW pump to the 32
SG) are all routed through Fire Zone 60A. The licensee also stated that
there are no ignition sources, other than cables, located less than 20
feet horizontally from the cables. The licensee further stated that no
cables associated with the 31 AFW pump, its flow control valves (FCV-
406A to 31 SG, FCV-406B to 32 SG), or its power source (Bus 3A) are
routed through this fire area but that the protected instrumentation
credited in this fire area for monitoring steam generator (SG) level is
the instrumentation for the 33 SG and 34 SG, which would make the 31
AFW pump an unsuitable choice if all level instrumentation for 31 and
32 SG has been rendered inoperable by fire damage. The licensee also
stated that the anticipated fire is a slow developing cable fire
located in the cable trays. The licensee also stated that Conduit 1VA/
JA (source range flux N31 instrumentation) is protected with fire
barrier wrap from penetration H-20 in Fire Zone 73A through the upper
electrical tunnel. As discussed in Section 3.0 above, the licensee did
not identify any separation between credited and redundant trains of
equipment.
3.3.4 OMAs Credited for a Fire in Fire Area ETN-4{1{time} (Fire Zone
60A)
3.3.4.1 OMA 5--Operate HCV-1118 Manually To Control 32 AFW
Pump
In the event that a fire occurs and causes a loss of the CCR
control or indication for all AFW pumps, the licensee stated that OMA
5 is available to restore this function by manually operating
HCV-1118 to control the 32 AFW pump. If OMA 5 becomes
necessary, the licensee stated that they have assumed a 4.5-minute
diagnosis period following the failure and that the required time to
perform the action is 17 minutes while the time available is 30
minutes, which provides 8.5 minutes of margin.
3.3.4.2 OMA 6--Align Appendix R Diesel Generator to 480 V
Buses 2A, 3A, 5A, and 312
The licensee stated that in the event of a loss of offsite power,
the use of the ARDG is credited for supplying power to the 480V buses
in the event of a fire in Fire Area ETN-4{1{time} . In the event that a
fire occurs and causes a loss of the CCR control or indication for the
buses, the licensee stated that OMA 6 is available to align
the ARDG to 480V buses 2A, 3A, 5A, and 312. If OMA 6 becomes
necessary, the licensee stated that they have assumed a loss of offsite
power at the outset of the event and that the required time to perform
the action is 50 minutes while the time available is 75 minutes, which
provides 25 minutes of margin. The NRC staff notes that this is
equivalent to implementing an alternate safe shutdown system in
accordance with III.G.3 and does not qualify for a III.G.2 exemption as
requested by the licensee.
3.3.4.3 OMA 7--Swap 31 or 32 Charging Pump To Alternate Power
Supply
In the event that a fire occurs and causes a loss of the CCR
control or indication for all charging pumps, the licensee stated that
OMA 7 is available to restore this function by swapping the 31
or 32 charging pump to its alternate power supply. If OMA 7
becomes necessary, the licensee stated that they have assumed a 30-
minute diagnosis period and that the required time to perform the
action is 8 minutes while the time available is 75 minutes, which
provides 37 minutes of margin.
3.3.4.4 OMA 8--Locally Operate FCV-405B, FCV-405D, or FCV-406B
To Control AFW Flow to Steam Generators
In the event that a fire occurs and causes a loss of the CCR
control or indication for all AFW flow control valves, the licensee
stated that OMA 8 is available to restore this function by
locally operating FCV-405B, FCV-405D, or FCV-406B to control AFW flow
to the SGs. If OMA 8 becomes necessary, the licensee stated
that they have assumed a 4.5-minute diagnosis period and that the
required time to perform the action is 17 minutes while the time
available is 30 minutes, which provides 8.5 minutes of margin.
3.3.4.5 OMA 9--Locally Open Valve 227 To Establish Charging
Makeup Flowpath to RCS
The licensee stated that OMA 9 is only required if normal
flowpath valve HCV-142 fails closed and that spurious isolation of the
charging makeup path to the RCS is identified in the CCR by operators
confirming that a charging pump is in operation, but pressurizer level
is decreasing, or pressurizer level channels are nonfunctional or
erratic in operation. The licensee also stated that the anticipated
fire is a slow developing cable fire located in the cable trays.
In the event that a fire occurs and causes the normal flowpath
valve HCV-142 to close, the licensee stated that OMA 9 is
available to restore this function by locally opening bypass valve 227
to establish the charging makeup flowpath to the RCS. If OMA 9
becomes necessary, the licensee stated that they have assumed a 60-
minute period before re-entering the fire area, a 30-minute diagnosis
period, which is assumed to transpire during the 60-minute waiting
period and that the required time to perform the action is 9 minutes
while the time available is 75
[[Page 8911]]
minutes, which provides 6 minutes of margin.
3.3.4.6 OMA 10--Locally Close Valve LCV-112C and Open Valve
288 To Align Charging Pump Suction to RWST
The licensee stated that preemptive steps in procedure 3-ONOP-FP-1,
``Plant Fires,'' for a fire scenario will trigger action via 3-AOP-SSD-
1, ``Control Room Inaccessibility Safe Shutdown Control,'' to locally
verify the charging pump suction path and perform the stated OMA prior
to starting a charging pump. 3-AOP-CVCS-1, ``Chemical And Volume
Control System Malfunctions,'' provides guidance to be followed in the
event that a swap of the charging pump suction to the RWST cannot be
confirmed (i.e., loss of CCR indication for valves LCV-112C [volume
control tank to charging pump suction] or LCV-112B [refueling water
storage tank to charging pump suction]), which will also trigger the
OMA. The licensee also stated that the anticipated fire is a slow
developing cable fire located in the cable trays.
In the event that a fire occurs and causes a loss of the CCR
control or indication for valves LCV-112C or LCV-112B, the licensee
stated that OMA 10 is available to restore this function by
locally closing valve LCV-112C and opening valve 288 to align the
charging pump suction to the RWST. If OMA 10 becomes
necessary, the licensee stated that they have assumed a 60-minute
period before re-entering the fire area, a 30-minute diagnosis period,
which is assumed to transpire during the 60-minute waiting period and
that the required time to perform the action is 11 minutes while the
time available is 75 minutes, which provides 4 minutes of margin.
3.3.4.7 OMA 11--Locally Operate PCV-1139 To Ensure Steam
Supply to 32 AFW Pump
The licensee stated that OMA 11 is only required if 32 AFW
pump is selected as the credited pump and other OMAs related to the 31
AFW pump are unsuccessful. The licensee also stated that the
anticipated fire is a slow developing cable fire located in the cable
trays.
In the event that a fire occurs and causes a loss of AFW flow
indication, loss of AFW pump, or loss of PCV-1139 indication from the
CCR, the licensee stated that OMA 11 is available to restore
this function by locally operating PCV-1139 to ensure a steam supply to
the 32 AFW pump. If OMA 11 becomes necessary, the licensee
stated that they have assumed a 4.5-minute diagnosis period and that
the required time to perform the action is 17 minutes while the time
available is 30 minutes, which provides 8.5 minutes of margin.
3.3.4.8 OMA 12--Locally Operate PCV-1310A and PCV-1310B To
Ensure Steam Supply to 32 AFW Pump
The licensee stated that OMA 12 is only required if the 32
AFW pump is selected as the credited pump. The licensee also stated
that the anticipated fire is a slow developing cable fire located in
the cable trays.
In the event that a fire occurs and causes a loss of steam supply
as diagnosed during local operation of the 32 AFW pump, the licensee
stated that OMA 12 is available to restore this function by
locally operating PCV-1310A and 1310B to ensure a steam supply to the
32 AFW pump. If OMA 12 becomes necessary, the licensee stated
that they have assumed a 4.5-minute diagnosis period and that the
required time to perform the action is 17 minutes while the time
available is 30 minutes, which provides 8.5 minutes of margin.
3.3.4.9 OMA 13--Locally Manually Perform SW Pump Strainer
Backwash, as Required
In an inspection report dated July 11, 2011 (ML111920339), NRC
inspectors identified that this OMA was inappropriate because it was
too complex and beyond the limited scope of an OMA to achieve and
maintain post-fire hot shutdown. Therefore, the NRC staff finds that it
is inappropriate to approve this OMA.
3.3.5 Conclusion for Fire Area ETN-4{1{time} (Fire Zone 60A)
The NRC staff had previously issued exemptions for Fire Zone 60A in
1987 (ML003779008) and in 1984 (ML003779284). In those exemptions, the
NRC staff found that the fire detection system, the automatic fire
suppression system, and the distance between redundant trains would
provide reasonable assurance that one train of shutdown equipment would
be available following a fire in this fire zone. The NRC staff finds
the defense-in-depth features in this fire zone and the available time
margin would allow the use of OMA 7. However, based on new
information in the current submittal the NRC staff finds that OMA
6 is equivalent to implementing an alternate safe shutdown
system in accordance with III.G.3 and does not qualify for a III.G.2
exemption as requested by the licensee. Also, the previous exemption
requests did not mention that OMA 13, SW pump strainer
backwash, was needed for the safe shutdown of the plant. Based on the
discussion in section 3.3.4.9, the NRC staff finds it inappropriate to
approve OMA 13. Also, OMAs 5, 8, 9, 10, 11, and 12
have insufficient available time margin to allow for reliable
performance considering the potential variables as discussed in NUREG-
1852. Therefore, the NRC staff finds that an exemption from III.G.2
based on these OMAs cannot be granted for Fire Zone 60A.
3.4 Fire Area ETN-4{3{time} --Electrical Tunnels (Fire Zone 73A--Upper
Electrical Penetration Area, Elevation 46'-0'')
3.4.1 Fire Prevention
The licensee stated that the fire loading in this area is moderate
and that the fixed combustibles are cable insulation and incidental
materials and that there are no transient combustibles. The licensee
also stated that the ignition sources in the area consist of cables,
junction boxes, electrical cabinets, and a transformer.
3.4.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 73A has an area-wide, automatic
ionization smoke detection system installed that was designed and
installed in accordance with NFPA 72E, 1974 Edition. The licensee also
stated that Fire Zone 73A has a dry-pipe, preaction sprinkler fire
suppression system installed in the cable trays that was designed and
installed in accordance with NFPA 13, 1978 Edition and NFPA 15, 1977
Edition.
3.4.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 73A has a ceiling height of
approximately 17'-0Prime; and an approximate floor area of 1,350 square
feet. As discussed in Section 3.0 above, the licensee did not identify
any separation between credited and redundant trains of equipment.
3.4.4 OMAs Credited for a Fire in Fire Area ETN-4{3{time} (Fire Zone
73A)
3.4.4.1 OMA 14--Operate HCV-1118 Manually To Control 32 AFW
Pump
The licensee stated that cable JBI-TA5 for valve HCV-1118 is
located in Fire Zone 73A in a cable tray located approximately 13 to 14
feet above the floor. The licensee also stated that ignition sources
located less than 20 feet horizontally from the cable consist of cables
and eight electrical cabinets. According to the licensee, two of the
electrical cabinets are separated from the cable by approximately 5.7
to 6.7
[[Page 8912]]
feet vertically and the remaining electrical cabinets are separated
from the cable by approximately 5.3 feet horizontally. The licensee
further stated that no cables associated with the 31 AFW pump, its flow
control valves (FCV-406A, FCV-406B), or its power source (Bus 3A) are
routed through this fire area, but that the protected instrumentation
credited in this fire area for monitoring SG level is the
instrumentation for the 33 SG and the 34 SG, which would make the 31
AFW pump an unsuitable choice if all level instrumentation for 31 and
32 SG has been rendered inoperable by fire damage. The licensee also
stated that the anticipated fire is a slow developing cable fire
located in the cable trays.
In the event that a fire occurs and causes a loss of the CCR
control or indication for all AFW pumps, the licensee stated that OMA
14 is available to restore this function by manually operating
HCV-1118 to control the 32 AFW pump. If OMA 14 becomes
necessary, the licensee stated that they have assumed a 4.5-minute
diagnosis period and that the required time to perform the action is 17
minutes while the time available is 30 minutes, which provides 8.5
minutes of margin.
3.4.4.2 OMA 15--Locally Operate PCV-1139 To Ensure Steam
Supply to 32 AFW Pump
The licensee stated that cable JB1-PT2/3 for valve PCV-1139 is
located in Fire Zone 73A in a cable tray located approximately 13 to 14
feet above the floor. The licensee also stated that ignition sources
located less than 20 feet horizontally from the cable consist of cables
and eight electrical cabinets. According to the licensee, two of the
electrical cabinets are separated from the cable by approximately 5.7
to 6.7 feet vertically and the remaining electrical cabinets are
separated from the cable by approximately 5.3 feet horizontally. The
licensee further stated that OMA 15 is only required if 32 AFW
pump is selected as the credited pump and other OMAs related to the 31
AFW pump are unsuccessful. The licensee also stated that the
anticipated fire is a slow developing cable fire located in the cable
trays.
In the event that a fire occurs and causes a loss of AFW flow
indication, loss of AFW pump, or loss of PCV-1139 indication from the
CCR, the licensee stated that OMA 15 is available to restore
this function by locally operating PCV-1139 to ensure steam supply to
the 32 AFW pump. If OMA 15 becomes necessary, the licensee
stated that they have assumed a 4.5-minute diagnosis period and that
the required time to perform the action is 17 minutes while the time
available is 30 minutes, which provides 8.5 minutes of margin.
3.4.4.3 OMA 16--Locally Operates PCV-1310A and PCV-1310B To
Ensure Steam Supply to 32 AFW Pump
The licensee stated that cables JB1-X02 and JB1-S99 for valves PCV-
1310A and PCV-1310B are located in Fire Zone 73A. The licensee also
stated that ignition sources located less than 20 feet horizontally
from the cables consist of cables and eight electrical cabinets.
According to the licensee, two of the electrical cabinets are separated
from the cables by approximately 5.7 to 6.7 feet vertically and the
remaining electrical cabinets are separated from the cables by
approximately 5.3 feet horizontally.
The licensee also stated that cables JB1-XO2/1 and JB1-SZ6 for
valves PCV-1310A and PCV-1310B are located in Fire Zone 73A in a cable
tray located approximately 13 feet above the floor. The licensee also
stated that ignition sources located less than 20 feet horizontally
from the cables consist of cables and eight electrical cabinets.
According to the licensee, three of the electrical cabinets are
separated from the cables by at least 4 feet vertically, two electrical
cabinets are separated from the cables by approximately 2.3 feet
horizontally and 2.3 feet vertically, and the remaining three
electrical cabinets are separated from the cables by approximately 10.2
feet horizontally. The licensee further stated that OMA 16 is
only required if the 32 AFW pump is selected as the credited pump. The
licensee also stated that the anticipated fire is a slow developing
cable fire located in the cable trays.
In the event that a fire occurs and causes a loss of steam supply
as diagnosed during local operation of the 32 AFW pump, the licensee
stated that OMA 16 is available to restore this function by
locally operating PCV-1310A and 1310B to ensure steam supply to the 32
AFW pump. If OMA 16 becomes necessary, the licensee stated
that they have assumed a 4.5-minute diagnosis period and that the
required time to perform the action is 17 minutes while the time
available is 30 minutes, which provides 8.5 minutes of margin.
3.4.4.4 OMA 17--Locally Operate FCV-405B, FCV-405D, or FCV-
406B To Control AFW Flow to Steam Generators
The licensee stated that cables JB1-KV8 and JB1-KV7 for valves FCV-
405C and FCV-405D are located in Fire Zone 73A in a cable tray located
approximately 13 to 14 feet above the floor. The licensee also stated
that ignition sources located less than 20 feet horizontally from the
cables consist of cables and eight electrical cabinets. According to
the licensee, two of the electrical cabinets are separated from the
cables by approximately 5.7 to 6.7 feet vertically and the remaining
electrical cabinets are separated from the cables by approximately 5.3
feet horizontally. The licensee further stated that the postulated fire
scenario would involve a fire that causes damage to the cables serving
the AFW FCVs in the area.
In the event that a fire occurs and causes a loss of the CCR
control or indication for all AFW flow control valves, the licensee
stated that OMA 17 is available to restore this function by
locally operating FCV-405B, FCV-405D, or FCV-406B to control AFW flow
to the steam generators. If OMA 17 becomes necessary, the
licensee stated that they have assumed a 4.5-minute diagnosis period
and that the required time to perform the action is 17 minutes while
the time available is 30 minutes, which provides 8.5 minutes of margin.
3.4.5 Conclusion for Fire Area ETN-4{3{time} (Fire Zone 73A)
The NRC staff had previously issued exemptions for Fire Zone 73A in
1987 (ML003779008) and in 1984 (ML003779284). In those exemptions, the
NRC staff found that the fire detection system, the automatic fire
suppression system, the distance between redundant trains, and the use
of the alternate safe shutdown system would provide reasonable
assurance that one train of shutdown equipment would be available
following a fire in this fire zone. In the current exemption request
the licensee did not credit the alternate safe shutdown system, but
instead proposed certain OMAs. The NRC staff finds that OMAs
14, 15, 16, and 17 have insufficient available time margin to
allow for reliable performance considering the potential variables as
discussed in NUREG-1852. Therefore, the NRC staff finds that an
exemption from III.G.2 based on these OMAs cannot be granted for Fire
Zone 73A.
3.5 Fire Area PAB-2{3{time} --Primary Auxiliary Building (Fire Zone 6--
32 Charging Pump Room, Elevation 55'-0'')
3.5.1 Fire Prevention
The licensee stated that the fire loading in this area is moderate
and that the fixed combustibles are cable insulation, lube oil, and
incidental materials and that transient combustibles consist of lube
oil, solvent, grease, cleaning materials, wood, anti-
[[Page 8913]]
contamination clothing (anti-C's), and plastic. The licensee also
stated that the ignition sources in the area consist of cables, a
junction box, an electrical cabinet, a motor, and a pump.
3.5.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 6 has an area-wide, automatic
ionization smoke detection system installed that was designed and
installed in accordance with NFPA 72E, 1974 Edition but that Fire Zone
6 does not have an automatic fire suppression system installed.
3.5.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 6 has a ceiling height of
approximately 16'-0'' and an approximate floor area of 288 square feet.
As discussed in Section 3.0 above, the licensee did not identify any
separation between credited and redundant trains of equipment.
3.5.4 OMAs Credited for a Fire in Fire Area PAB-2{3{time} (Fire Zone
6)
3.5.4.1 OMA 18--Locally Close LCV-112C and Open Valve 288 To
Align Charging Pump Suction Path to RWST
The licensee stated that cable DD4-VN3 for valve LCV-112C is
located in Fire Zone 6 in conduit located approximately 14 feet above
the floor and terminates at LCV-112B, which is located approximately
7.5 feet above the floor. The licensee also stated that ignition
sources located less than 20 feet horizontally from the cable consist
of cables, the charging pump motor, and a transfer switch. According to
the licensee, the motor is separated from the cable by approximately
13.8 feet horizontally and the transfer switch is separated from the
cable by approximately 16 feet horizontally.
The licensee also stated that cable DD4-VN3 is an interlock cable
that interfaces with RWST outlet valve LCV-112B and that fire-induced
failures of this cable could cause the spurious closure of LCV-112C. In
addition, the licensee stated that preemptive steps in 3-ONOP-FP-1 to
secure the 31 and 32 charging pumps early in the fire scenario will
trigger action via 3-AOP-SSD-1 to locally verify charging pump suction
path and perform OMA 18 prior to starting a charging pump. 3-
AOP-CVCS-1 provides guidance to be followed in the event that the swap
of charging pump suction to the RWST cannot be confirmed (i.e., loss of
CCR indication for valves LCV-112C or LCV-112B), which will also
trigger OMA 18.
In the event that a fire occurs and causes a loss of the CCR
control or indication for valves LCV-112C or LCV-112B, the licensee
stated that OMA 18 is available to restore this function by
locally closing LCV-112C and opening valve 288 to align the charging
pump suction path to RWST. If OMA 18 becomes necessary, the
licensee stated that they have assumed a 60-minute period before re-
entering the fire area, an 11-minute diagnosis period, which is assumed
to transpire during the 60-minute waiting period, and that the required
time to perform the action is 11 minutes while the time available is 75
minutes, which provides 4 minutes of margin.
3.5.5 Conclusion for Fire Area PAB-2{3{time} (Fire Zone 6)
Although there is 4 minutes of margin available for OMA
18, Fire Zone 6 has moderate combustible loading, lacks
automatic fire suppression, and the licensee did not provide details
regarding any discernable separation between the credited and redundant
equipment so it is not clear that at least one train of equipment would
remain free of fire damage during or following a fire event. The NRC
staff finds that OMA 18 has insufficient available time margin
to allow for reliable performance considering the potential variables
as discussed in NUREG-1852. Therefore, the NRC staff finds that the
defense-in-depth is insufficient to demonstrate reasonable assurance
that safe shutdown can be achieved for a fire in Fire Zone 6 and finds
that OMA 18 is unacceptable for the purpose of providing the
level of protection intended by the regulation and that an exemption
from III.G.2 based on OMA 18 cannot be granted for Fire Zone
6.
3.6 Fire Area PAB-2{5{time} --Primary Auxiliary Building (Fire Zone
17A--Elevation 55'-0', PAB Corridor)
3.6.1 Fire Prevention
The licensee stated that the fire loading in this area is low and
that the fixed combustibles are cable insulation, incidental materials,
cellulose, resin, hydrogen, rubber, and plastic and that transient
combustibles consist of solvent, lube oil, cleaning materials, grease,
paper, wood, anti-C's, and plastic. The licensee also stated that the
ignition sources in the area consist of cables, junction boxes, motor
control centers (MCCs), transformers, a water heater, lighting power
supply, an instrument panel, and electrical cabinets.
3.6.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 17A has ionization smoke
detectors installed in the under-floor area at MCC Nos. 36A, 36B, and
37 and ultraviolet detectors in the MCC area but that Fire Zone 17A
does not have an automatic fire suppression system installed. The
licensee also stated that the fire detection systems were designed and
installed in accordance with NFPA 72E, 1974 Edition.
3.6.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 17A has a ceiling height of
approximately 16'-0'' and an approximate floor area of 6,386 square
feet. The licensee also stated that there are fire barriers, in the
form of marinate boards, installed over the cable trays.
The licensee stated that cable DD4-VN3 for valve LCV-112C is
located in Fire Zone 17A in a tray located approximately 14 feet above
the floor. The licensee also stated that ignition sources located less
than 20 feet horizontally from the cable consist of cables, MCC panels,
lighting power panels, electrical cabinets, and instrument panels.
According to the licensee, the MCCs and lighting power panels are
separated from the cable by approximately 7.4 feet horizontally, three
electrical cabinets are located under the cable separated by
approximately 3.5 feet vertically, and the rest of the electrical
cabinets are separated from the cabinet by approximately 5.6 feet
horizontally. The licensee also stated that cable DD4-VN3 is an
interlock cable that interfaces with RWST outlet valve LCV-112B and
that fire-induced failures of this cable could cause the spurious
closure of LCV-112C.
The licensee also stated that cables DD4-VN5/1 and DD4-VN5/2 for
valve LCV-112C are located in Fire Zone 17A in a tray located
approximately 14 feet above the floor. The licensee also stated that
ignition sources located less than 20 feet horizontally from the cable
consist of cables, MCC panels, lighting power panels, electrical
cabinets, and instrument panels. According to the licensee, the MCCs
and lighting power panels are separated from the cables by
approximately 7.4 feet horizontally, three electrical cabinets are
located under the cables separated by approximately 3.5 feet
vertically, and the rest of the electrical cabinets are separated from
the cables by approximately 5.6 to 10 feet horizontally.
[[Page 8914]]
The licensee also stated that cables AH9-PL2 and JA4-PL2/2 for the
32 charging pump are located in Fire Zone 17A in a tray located
approximately 10 to 12 feet above the floor. The licensee also stated
that ignition sources located less than 20 feet horizontally from the
cable consist of cables, an instrument panel, 21 electrical cabinets,
and one dry transformer. According to the licensee, the instrument
panel and 12 of the electrical cabinets are located under the cables
separated from the cables by approximately 4.2 feet vertically, the
remaining 9 electrical cabinets are separated from the cables by
approximately 4.2 feet horizontally, and the dry transformer is
separated from the cables by approximately 15.8 feet horizontally.
As discussed in Section 3.0 above, the licensee did not identify
any separation between credited and redundant trains of equipment.
3.6.4 OMAs Credited for a Fire in Fire Area PAB-2{5{time} (Fire Zone
17A)
3.6.4.1 OMA 19--Locally Close Supply Breaker for 32 Charging
Pump
In the event that a fire occurs and causes a failure of the CCR
control switch response, or indicating lights prompt operators to
investigate breaker status at the switchgear, the licensee stated that
OMA 19 is available to restore this function by locally
closing the supply breaker for the 32 charging pump. The supply breaker
is located in a different fire area. If OMA 19 becomes
necessary, the licensee stated that they have assumed a 30-minute
diagnosis period and that the required time to perform the action is 7
minutes while the time available is 75 minutes, which provides 38
minutes of margin.
3.6.4.2 OMA 20--Locally Control 32 Charging Pump Using Scoop
Tube Positioner
In the event that a fire occurs and causes damage to the cables
serving both the 31 and 32 charging pumps or causes a loss of CCR pump
control or pump status indication, the licensee stated that OMA
20 is available to restore this function by locally
controlling the 32 charging pump using the scoop tube positioner. If
OMA 20 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 9 minutes while the time available is 75 minutes,
which provides 36 minutes of margin.
3.6.4.3 OMA 22--Locally Close LCV-112C and Open Bypass Valve
288 To Establish Flowpath From RWST to Charging Pump Suction
The licensee stated that preemptive steps in procedure 3-ONOP-FP-1
to secure the 31 and 32 charging pumps early in the fire scenario will
trigger action via 3-AOP-SSD-1 to locally verify charging pump suction
path and perform OMA 22 prior to starting a charging pump. 3-
AOP-CVCS-1 provides guidance to be followed in the event that swap of
charging pump suction to RWST cannot be confirmed (i.e., loss of CCR
indication for valves LCV-112C or LCV-112B), which will also trigger
OMA 22.
In the event that a fire occurs and causes a loss of the CCR
control or indication for valves LCV-112C or LCV-112B, the licensee
stated that OMA 22 is available to restore this function by
locally closing LCV-112C and open bypass valve 288 to establish a
flowpath from the RWST to the charging pump suction. If OMA 22
becomes necessary, the licensee stated that they have assumed a 60-
minute period before re-entering the fire area, a 30-minute diagnosis
period, which is assumed to transpire during the 60-minute waiting
period and that the required time to perform the action is 11 minutes
while the time available is 75 minutes, which provides 4 minutes of
margin.
3.6.5 Conclusion for Fire Area PAB-2{5{time} (Fire Zone 17A)
There are 38 minutes of margin and 36 minutes of margin available
for OMAs 19 and 20, respectively, automatic fire
detection systems installed, and these two particular OMAs have
sufficient time margin available. The staff finds that there is
adequate defense-in-depth to support the use of OMAs 19 and
20 for Fire Zone 17A and that OMAs 19 and 20
are acceptable for this fire zone.
Although there is 4 minutes of margin available for OMA
22, Fire Zone 17A lacks automatic fire suppression, and the
licensee did not provide details regarding any discernable separation
between the credited and redundant equipment so it is not clear that at
least one train of equipment would remain free of fire damage during or
following a fire event. The NRC staff finds that OMA 22 has
insufficient available time margin to allow for reliable performance
considering the potential variables as discussed in NUREG-1852.
Therefore, the NRC staff finds that the defense-in-depth is
insufficient to demonstrate reasonable assurance that safe shutdown can
be achieved for a fire in Fire Zone 17A and finds that an exemption
from III.G.2 based on OMA 22 cannot be granted for Fire Zone
17A. The NRC previously granted an exemption for Fire Zone 17A dated
January 7, 1987 (ML003779008), but that exemption also credited the use
of the IP3 alternate safe shutdown system. The IP3 alternate safe
shutdown system was not evaluated here as the licensee only requested
consideration for the OMAs.
3.7 Fire Area PAB-2{5{time} --Primary Auxiliary Building (Fire Zone
19A--Waste Evaporator Room, Elevation 55'-0'')
3.7.1 Fire Prevention
The licensee stated that the fire loading in this area is low and
that the fixed combustibles are cable insulation and incidental
materials and that transient combustibles consist of wood, anti-C's,
and plastic. The licensee also stated that the ignition sources in the
area consist of cables, a junction box, transformers, and electrical
cabinets.
3.7.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 19A does not have a fire
detection or automatic fire suppression system installed.
3.7.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 19A has a ceiling height of
approximately 16'-0'' and an approximate floor area of 602 square feet.
The licensee stated that cables AH9-PL2 and JA4-PL2/2 for the 32
charging pump are located in Fire Zone 19A in conduit located
approximately 10 to 12 feet above the floor. The licensee also stated
that ignition sources located less than 20 feet horizontally from the
cable consist of cables, an instrument panel, 21 electrical cabinets,
and a dry transformer. According to the licensee, the instrument panel
and 12 of the electrical cabinets are located under the cables
separated from the cables by approximately 4.2 feet vertically, the
remaining 9 electrical cabinets are separated from the cables by
approximately 4.2 feet horizontally, and the dry transformer is
separated from the cables by approximately 15.8 feet horizontally.
As discussed in Section 3.0 above, the licensee did not identify
any separation between credited and redundant trains of equipment.
[[Page 8915]]
3.7.4 OMAs Credited for a Fire in Fire Area PAB-2{5{time} (Fire Zone
19A)
3.7.4.1 OMA 19--Locally Close Supply Breaker for 32 Charging
Pump
In the event that a fire occurs and causes a failure of the CCR
control switch response or indicating lights prompt operators to
investigate breaker status at the switchgear, the licensee stated that
OMA 19 is available to restore this function by locally
closing the supply breaker for the 32 charging pump. The supply breaker
is located in a different fire area. If OMA 19 becomes
necessary, the licensee stated that they have assumed a 30-minute
diagnosis period and that the required time to perform the action is 7
minutes while the time available is 75 minutes, which provides 38
minutes of margin.
3.7.4.2 OMA 20--Locally Control 32 Charging Pump Using Scoop
Tube Positioner
In the event that a fire occurs and causes damage to the cables
serving both the 31 and 32 charging pumps or causes a loss of CCR pump
control or pump status indication, the licensee stated that OMA
20 is available to restore this function by locally
controlling the 32 charging pump using the scoop tube positioner. If
OMA 20 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 9 minutes while the time available is 75 minutes,
which provides 36 minutes of margin.
3.7.5 Conclusion for Fire Area PAB-2{5{time} (Fire Zone 19A)
Although there is 38 minutes of margin and 36 minutes of margin
available for OMAs 19 and 20, respectively, Fire Zone
19A lacks fire detection and automatic suppression systems and the
licensee did not provide details regarding any discernable separation
between the credited and redundant equipment and clear and direct
procedures that instruct operators to proactively perform the OMAs, so
it is not clear that at least one train of equipment would remain free
of fire damage during or following a fire event. Therefore, the NRC
staff finds that the defense-in-depth is insufficient to demonstrate
reasonable assurance that safe shutdown can be achieved for a fire in
Fire Zone 19A and finds that an exemption from III.G.2 based on OMAs
19 and 20 cannot be granted for Fire Zone 19A.
3.8 Fire Area PAB-2{5{time} --Primary Auxiliary Building (Fire Zone
20A--Sample Room, Elevation 55'-0'')
3.8.1 Fire Prevention
The licensee stated that the fire loading in this area is moderate
and that the fixed combustibles are cable insulation and incidental
materials and that transient combustibles consist of wood, solvent,
cleaning materials, anti-C's, and plastic. The licensee also stated
that the ignition sources in the area consist of cables and junction
boxes.
3.8.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 20A does not have a fire
detection or automatic suppression system installed.
3.8.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 20A has a ceiling height of
approximately 14'-6'' and an approximate floor area of 210 square feet.
As discussed in Section 3.0 above, the licensee did not identify any
separation between credited and redundant trains of equipment.
3.8.4 OMAs Credited for a Fire in Fire Area PAB-2{5{time} (Fire Zone
20A)
3.8.4.1 OMA 22--Locally Close LCV-112C and Open Bypass Valve
288 To Establish Flowpath From RWST to Charging Pump Suction
The licensee did not describe which SSD cables are routed through
Fire Zone 20A. The licensee stated that preemptive steps in procedure
3-ONOP-FP-1 to secure the 31 and 32 charging pumps early in the fire
scenario will trigger action via 3-AOP-SSD-1 to locally verify charging
pump suction path and perform OMA 22 prior to starting a
charging pump. 3-AOP-CVCS-1 provides guidance to be followed in the
event that swap of charging pump suction to RWST cannot be confirmed
(i.e., loss of CCR indication for valves LCV-112C or LCV-112B), which
will also trigger OMA 22.
In the event that a fire occurs and causes a loss of the CCR
control or indication for valves LCV-112C or LCV-112B, the licensee
stated that OMA 22 is available to restore this function by
locally closing LCV-112C and open bypass valve 288 to establish a
flowpath from the RWST to the charging pump suction. If OMA 22
becomes necessary, the licensee stated that they have assumed a 60-
minute period before re-entering the fire area, a 30-minute diagnosis
period, which is assumed to transpire during the 60-minute waiting
period and that the required time to perform the action is 11 minutes
while the time available is 75 minutes, which provides 4 minutes of
margin.
3.8.5 Conclusion for Fire Area PAB-2 (Fire Zone 20A)
Although there is 4 minutes of margin available for OMA
22, Fire Zone 20A lacks automatic fire detection and
suppression systems and the licensee did not provide details regarding
any discernible separation between the credited and redundant equipment
so it is not clear that at least one train of equipment would remain
free of fire damage during or following a fire event. The NRC staff
finds that OMA 22 has insufficient available time margin to
allow for reliable performance considering the potential variables as
discussed in NUREG-1852. Therefore, the NRC staff finds that the
defense-in-depth is insufficient to demonstrate reasonable assurance
that safe shutdown can be achieved for a fire in Fire Zone 20A and
finds that an exemption from III.G.2 based on OMA 22 cannot be
granted for Fire Zone 20A.
3.9 Fire Area PAB-2{5{time} --Primary Auxiliary Building (Fire Zone
27A--Elevation 73'-0'' PAB Corridor)
3.9.1 Fire Prevention
The licensee stated that the fire loading in this area is low and
that the fixed combustibles are cable insulation, incidental materials,
cellulose, plastic, and a flammable liquid locker and that transient
combustibles consist of lube oil, grease, paper, wood, solvent,
cleaning materials, anti-C's, and plastic. The licensee also stated
that the ignition sources in the area consist of cables, a transformer,
a water heater, and junction boxes.
3.9.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 27A does not have a fire
detection or automatic suppression system installed.
3.9.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 27A has a ceiling height of
approximately 15'-6'' and an approximate floor area of 5,532 square
feet. The licensee stated that cables DD4-VN5/1 and DD4-VN5/2 for valve
LCV-112C are located in Fire Zone 27A in a conduit or tray located
approximately 12 feet above the floor. The licensee also stated that
ignition sources located less than 20 feet horizontally from the cable
consist of cables, electrical cabinets, and a dry transformer.
According to the licensee, one of the electrical cabinets is located
[[Page 8916]]
under the cables separated from the cables by approximately 6.8 feet
vertically, the remaining electrical cabinets are separated from the
cables by approximately 11.9 feet horizontally, and the dry transformer
is located under the cables separated from the cables by approximately
3.5 feet vertically. As discussed in Section 3.0 above, the licensee
did not identify any separation between credited and redundant trains
of equipment.
3.9.4 OMAs Credited for a Fire in Fire Area PAB-2{5{time} (Fire Zone
27A)
3.9.4.1 OMA 22--Locally Close LCV-112C and Open Bypass Valve
288 To Establish Flowpath From RWST to Charging Pump Suction
The licensee stated that preemptive steps in procedure 3-ONOP-FP-1
to secure the 31 and 32 charging pumps early in the fire scenario will
trigger action via 3-AOP-SSD-1 to locally verify charging pump suction
path and perform OMA 22 prior to starting a charging pump. 3-
AOP-CVCS-1 provides guidance to be followed in the event that swap of
charging pump suction to RWST cannot be confirmed (i.e., loss of CCR
indication for valves LCV-112C or LCV-112B), which will also trigger
OMA 22.
In the event that a fire occurs and causes a loss of the CCR
control or indication for valves LCV-112C or LCV-112B, the licensee
stated that OMA 22 is available to restore this function by
locally closing LCV-112C and open bypass valve 288 to establish a
flowpath from the RWST to the charging pump suction. If OMA 22
becomes necessary, the licensee stated that they have assumed a 60-
minute period before re-entering the fire area, a 30-minute diagnosis
period, which is assumed to transpire during the 60-minute waiting
period and that the required time to perform the action is 11 minutes
while the time available is 75 minutes, which provides 4 minutes of
margin.
3.9.5 Conclusion for Fire Area PAB-2{5{time} (Fire Zone 27A)
Although there is 4 minutes of margin available for OMA
22, Fire Zone 27A lacks fire detection and automatic
suppression systems and the licensee did not provide details regarding
any discernable separation between the credited and redundant equipment
so it is not clear that at least one train of equipment would remain
free of fire damage during or following a fire event. The NRC staff
finds that OMA 22 has insufficient available time margin to
allow for reliable performance considering the potential variables as
discussed in NUREG-1852. Therefore, the NRC staff finds that the
defense-in-depth is insufficient to demonstrate reasonable assurance
that safe shutdown can be achieved for a fire in Fire Zone 27A and
finds that an exemption from III.G.2 based on OMA 22 cannot be
granted for Fire Zone 27A.
3.10 Fire Area PAB-2{5{time} --Primary Auxiliary Building (Fire Zone
30A--Valve Corridor, Elevation 73'-0'')
3.10.1 Fire Prevention
The licensee stated that the fire loading in this area is moderate
and that the fixed combustibles are cable insulation and incidental
materials and that transient combustibles consist of lube oil, grease,
wood, solvent, cleaning materials, anti-C's, and plastic. The licensee
also stated that the ignition sources in the area consist of cables.
3.10.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 30A does not have a fire
detection or automatic suppression system installed.
3.10.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 30A has a ceiling height of
approximately 17'-0'' and an approximate floor area of 171 square feet.
The licensee stated that cables DD4-VN5/1 and DD4-VN5/2 for valve LCV-
112C are located in Fire Zone 30A in a conduit or tray located
approximately 2.5 to 12 feet above the floor. The licensee also stated
that ignition sources located less than 20 feet horizontally from the
cable consist of cables, electrical cabinets, and a dry transformer.
According to the licensee, the electrical cabinets are separated from
the cables by approximately 1.8 feet horizontally and the dry
transformer is located under the cables separated from the cables by
approximately 0.1 feet horizontally. As discussed in Section 3.0 above,
the licensee did not identify any separation between credited and
redundant trains of equipment.
3.10.4 OMAs Credited for a Fire in Fire Area PAB-2{5{time} (Fire Zone
30A)
3.10.4.1 OMA 22--Locally Close LCV-112C and Open Bypass Valve
288 To Establish Flowpath From RWST to Charging Pump Suction
The licensee stated that preemptive steps in procedure 3-ONOP-FP-1
to secure the 31 and 32 charging pumps early in the fire scenario will
trigger action via 3-AOP-SSD-1 to locally verify charging pump suction
path and perform OMA 22 prior to starting a charging pump. 3-
AOP-CVCS-1 provides guidance to be followed in the event that swap of
charging pump suction to RWST cannot be confirmed (i.e., loss of CCR
indication for valves LCV-112C or LCV-112B), which will also trigger
OMA 22.
In the event that a fire occurs and causes a loss of the CCR
control or indication for valves LCV-112C or LCV-112B, the licensee
stated that OMA 22 is available to restore this function by
locally closing LCV-112C and open bypass valve 288 to establish a
flowpath from the RWST to the charging pump suction. If OMA 22
becomes necessary, the licensee stated that they have assumed a 60-
minute period before re-entering the fire area, a 30-minute diagnosis
period, which is assumed to transpire during the 60-minute waiting
period and that the required time to perform the action is 11 minutes
while the time available is 75 minutes, which provides 4 minutes of
margin.
3.10.5 Conclusion for Fire Area PAB-2{5{time} (Fire Zone 30A)
Although there is 4 minutes of margin available for OMA
22, Fire Zone 30A has moderate combustible fuel loading, lacks
fire detection and automatic suppression systems and the licensee did
not provide details regarding any discernable separation between the
credited and redundant equipment so it is not clear that at least one
train of equipment would remain free of fire damage during or following
a fire event. The NRC staff finds that OMA 22 has insufficient
available time margin to allow for reliable performance considering the
potential variables as discussed in NUREG-1852. Therefore, the NRC
staff finds that the defense-in-depth is insufficient to demonstrate
reasonable assurance that safe shutdown can be achieved for a fire in
Fire Zone 30A and finds that an exemption from III.G.2 based on OMA
22 cannot be granted for Fire Zone 30A.
3.11 Fire Area PAB-2{5{time} --Primary Auxiliary Building (Fire Zone
58A--Piping Tunnel, Elevation 41'-0'')
3.11.1 Fire Prevention
The licensee stated that the fire loading in this area is low and
that the fixed combustibles are cable insulation and incidental
materials and that transient combustibles consist of lube oil, grease,
wood, solvent, cleaning materials, anti-C's, and plastic. The licensee
also stated that the ignition sources in the area consist of cables.
[[Page 8917]]
3.11.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 58A has an area-wide, ionization
smoke detection system designed and installed in accordance with NFPA
72E, 1974 Edition but does not have an automatic fire suppression
system installed.
3.11.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 58A has a ceiling height of
approximately 10'-0'' to 12'-0'' and an approximate floor area of 1,400
square feet. The licensee stated that cable K1B-W1B for the 32 charging
pump is located in Fire Zone 58A in a tray located approximately 9.5
feet above the floor. The licensee also stated that other than cables,
there are no ignition sources located less than 20 feet from the cable.
As discussed in Section 3.0 above, the licensee did not identify any
separation between credited and redundant trains of equipment.
3.11.4 OMAs Credited for a Fire in Fire Area PAB-2{5{time} (Fire Zone
58A)
3.11.4.1 OMA 19--Locally Close Supply Breaker for 32 Charging
Pump
In the event that a fire occurs and causes a failure of the CCR
control switch response, or indicating lights prompt operators to
investigate breaker status at the switchgear, the licensee stated that
OMA 19 is available to restore this function by locally
closing the supply breaker for the 32 charging pump. The supply breaker
is located in a different fire area. If OMA 19 becomes
necessary, the licensee stated that they have assumed a 30-minute
diagnosis period and that the required time to perform the action is 7
minutes while the time available is 75 minutes, which provides 38
minutes of margin.
3.11.4.2 OMA 20--Locally Control 32 Charging Pump Using Scoop
Tube Positioner
In the event that a fire occurs and causes damage to the cables
serving both the 31 and 32 charging pumps or causes a loss of CCR pump
control or pump status indication, the licensee stated that OMA
20 is available to restore this function by locally
controlling the 32 charging pump using the scoop tube positioner. If
OMA 20 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 9 minutes while the time available is 75 minutes,
which provides 36 minutes of margin.
3.11.5 Conclusion for Fire Area PAB-2{5{time} (Fire Zone 58A)
Since there is 38 minutes of margin and 36 minutes of margin
available for OMAs 19 and 20, respectively, an
automatic smoke detection system installed, and these two particular
OMAs have sufficient margin available, the staff finds that there is
adequate defense-in-depth to support the use of OMAs 19 and
20 for Fire Zone 58A and that OMAs 19 and 20
are acceptable for the purpose of providing the level of protection
intended by the regulation and that an exemption from III.G.2 based on
these OMAs is granted for Fire Zone 58A.
3.12 Fire Area PAB-2{5{time} --Primary Auxiliary Building (Fire Zone
59A--Pipe Penetration Area, Elevation 41'-0'' and 51'-0'' of the Fan
House)
3.12.1 Fire Prevention
The licensee stated that the fire loading in this area is low and
that the fixed combustibles are cable insulation and incidental
materials and that transient combustibles consist of grease, wood,
cleaning materials, anti-C's, and plastic. The licensee also stated
that the ignition sources in the area consist of cables and a junction
box.
3.12.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 59A has an area-wide, ionization
smoke detection system designed and installed in accordance with NFPA
72E, 1974 Edition but does not have an automatic fire suppression
system installed.
3.12.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 59A has a ceiling height of
approximately 8'-0'' to 26'-0'' and an approximate floor area of 3,782
square feet. The licensee stated that cables JB5-X1J and VK4-X1J for
valve HCV-142 are located in Fire Zone 59A in a tray located
approximately 6 to 26 feet above the floor. The licensee also stated
that ignition sources located less than 20 feet horizontally from the
cable consist of cables, an electrical cabinet, and 8 motors attached
to motor-operated valves. According to the licensee, the electrical
cabinet is located under the cables separated from the cables by
approximately 2.6 feet vertically and the motors are separated from the
cables by approximately 2.1 feet horizontally and no vertical
separation. As discussed in Section 3.0 above, the licensee did not
identify any separation between credited and redundant trains of
equipment.
3.12.4 OMAs Credited for a Fire in Fire Area PAB-2{5{time} (Fire Zone
59A)
3.12.4.1 OMA 21--Open Bypass Valve 227 To Establish Charging
Flow Path to RCS Around Potentially Failed Close HCV-142
In the event that a fire occurs and causes normal flowpath valve
HCV-142 to close, the licensee stated that OMA 21 is available
to restore this function by opening bypass valve 227 to establish a
charging flowpath to the RCS around the potentially failed close HCV-
142. If OMA 21 becomes necessary, the licensee stated that
they have assumed a 60-minute period before re-entering the fire area,
a 30-minute diagnosis period, which is assumed to transpire during the
60-minute waiting period and that the required time to perform the
action is 9 minutes while the time available is 75 minutes, which
provides 6 minutes of margin.
3.12.5 Conclusion for Fire Area PAB-2{5{time} (Fire Zone 59A)
Although there is 6 minutes of margin available for OMA
21, this OMA requires the operator to re-enter the fire area
after the fire has been extinguished. Fire Zone 59A contains credible
fire scenarios, lacks automatic fire suppression, and the licensee did
not provide details regarding any discernable separation between the
credited and redundant equipment and clear and direct procedures that
instruct operators to proactively perform the OMA so it is not clear
that at least one train of equipment would remain free of fire damage
during or following a fire event. The NRC staff finds that OMA
21 has insufficient available time margin to allow for
reliable performance considering the potential variables as discussed
in NUREG-1852. Therefore, the NRC staff finds that the defense-in-depth
is insufficient to demonstrate reasonable assurance that safe shutdown
can be achieved for a fire in Fire Zone 59A and finds that an exemption
from III.G.2 based on this OMA cannot be granted for Fire Zone 59A.
3.13 Fire Area TBL-5--Turbine Building (Fire Zone 37A--Ground Floor
South, Elevation 15'-0'')
3.13.1 Fire Prevention
The licensee stated that the fire loading in this area is low and
that the fixed combustibles are cable insulation, MCC switchgear,
cellulose, plastic, lube oil, and a flammable liquid cabinet and that
there are no transient combustibles. The licensee also stated that the
ignition sources in the area consist of cables, a junction box, a
battery with charger, electrical cabinets, transformers, a dryer,
[[Page 8918]]
6.9 kV switchgear vertical panels (potential high energy arcing fault
(HEAF) source), and MCC vertical panels.
3.13.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 37A has ionization smoke
detectors installed over MCC 34 and over the 6.9 kV switchgear, thermal
detection in the battery and charger room, a wet-pipe sprinkler system
installed throughout the area except over switchgear, and a wet pipe
sprinkler system installed throughout the battery and charger room. The
licensee also stated that the detection systems were designed and
installed in accordance with NFPA 72E, 1974 Edition and the fire
suppression systems were designed and installed in accordance with NFPA
13, 1983 Edition.
3.13.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 37A has a ceiling height of
approximately 119'-0'' (See TABLE RAI-GEN-15 of the licensee's May 4,
2010, letter, ML101320263) and an approximate floor area of 5,838
square feet. The licensee stated that cable AQ7-WF6 for the 31 SW
strainer is routed through Fire Zone 37A in a tray located
approximately 11.3 feet above the floor. The licensee also stated that
ignition sources located less than 20 feet horizontally from the cable
consist of cables, an MCC, 6.9 kV switchgear, and an electrical
cabinet. According to the licensee, the MCC and 6.9 kV switchgear are
located under the cable separated by approximately 3 feet vertically
and the electrical cabinet is separated from the cable by approximately
8.1 feet horizontally. As discussed in Section 3.0 above, the licensee
did not identify any separation between credited and redundant trains
of equipment.
3.13.4 OMAs Credited for a Fire in Fire Area TBL-5 (Fire Zone 37A)
3.13.4.1 OMA 25--Locally Manually Backwash SW Pump Strainer,
as Required, if Power to Strainer Associated With Selected SW Pump Is
Lost
The licensee stated that the need to periodically backwash a
selected SW strainer is variable depending on ultimate heat sink
conditions and other factors and that the diagnostic indicator to
perform the OMA is based on operator rounds monitoring pressure across
SW strainers. The licensee also stated that the anticipated fire is a
slow developing cable fire located in the cable trays.
In the event that a fire occurs and causes an increase in SW pump
strainer differential pressure or a loss of power to the strainer
associated with the selected SW pump, the licensee stated that OMA
25 is available to restore this function by locally manually
performing a SW pump strainer backwash. In an inspection report dated
July 11, 2011 (ML111920339), NRC inspectors identified that this OMA
was inappropriate because it was too complex and beyond the limited
scope of an OMA to achieve and maintain post-fire hot shutdown.
Therefore, the NRC staff finds that it is inappropriate to approve this
OMA.
3.13.5 Conclusion for Fire Area TBL-5 (Fire Zone 37A)
The NRC staff finds that the defense-in-depth is insufficient to
demonstrate reasonable assurance that safe shutdown can be achieved for
a fire in Fire Zone 37A and finds that OMA 25 is unacceptable
for the purpose of providing the level of protection intended by the
regulation and that an exemption from III.G.2 based on this OMA cannot
be granted for Fire Zone 37A.
3.14 Fire Area TBL-5--Turbine Building (Fire Zone 38A--Chemical
Laboratory, Elevation 15'-0'')
3.14.1 Fire Prevention
The licensee stated that the fire loading in this area is low and
that the fixed combustibles are cable insulation, an MCC, cellulose,
plastic, hydrogen, chemicals, and a flammable liquid cabinet and that
there are no transient combustibles. The licensee also stated that the
ignition sources in the area consist of an electrical cabinet and an
MCC.
3.14.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 38A has an ionization smoke
detector installed over MCC 32 and a wet-pipe sprinkler suppression
system installed in the chemical storage area. The licensee also stated
that the detection system was designed and installed in accordance with
NFPA 72E, 1974 Edition and the fire suppression system was designed and
installed in accordance with NFPA 13, 1983 Edition.
3.14.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 38A has a ceiling height of
approximately 8'-0'' and an approximate floor area of 4,500 square
feet. The licensee stated that cables AQ7-WF6 and WF6-Z99 for the 31 SW
strainer are routed through Fire Zone 38A in a tray or conduit that
traverses the area vertically. The licensee also stated that ignition
sources located less than 20 feet horizontally from the cables consist
of cables and 2 electrical cabinets. According to the licensee, the
electrical cabinets are separated from the cables by approximately 11.8
feet horizontally. The licensee further stated that the need to
periodically backwash a selected SW strainer is variable depending on
ultimate heat sink conditions and other factors and that the diagnostic
indicator to perform the OMA is based on operator rounds monitoring
pressure across SW strainers. The licensee also stated that the
anticipated fire is a slow developing cable fire located in the cable
trays. As discussed in Section 3.0 above, the licensee did not identify
any separation between credited and redundant trains of equipment.
3.14.4 OMAs Credited for a Fire in Fire Area TBL-5 (Fire Zone 38A)
3.14.4.1 OMA 25--Locally Manually Backwash SW Pump Strainer,
as Required, if Power to Strainer Associated With Selected SW Pump Is
Lost
The licensee stated that the need to periodically backwash a
selected SW strainer is variable depending on ultimate heat sink
conditions and other factors and that the diagnostic indicator to
perform the OMA is based on operator rounds monitoring pressure across
SW strainers.
In the event that a fire occurs and causes an increase in SW pump
strainer differential pressure or a loss of power to the strainer
associated with the selected SW pump, the licensee stated that OMA
25 is available to restore this function by locally manually
performing a SW pump strainer backwash. In an inspection report dated
July 11, 2011 (ML111920339), NRC inspectors identified that this OMA
was inappropriate because it was too complex and beyond the limited
scope of an OMA to achieve and maintain post-fire hot shutdown.
Therefore, the NRC staff finds that it is inappropriate to approve this
OMA.
3.14.5 Conclusion for Fire Area TBL-5 (Fire Zone 38A)
The NRC staff finds that the defense-in-depth is insufficient to
demonstrate reasonable assurance that safe shutdown can be achieved for
a fire in Fire Zone 37A and finds that OMA 25 is unacceptable
for the purpose of
[[Page 8919]]
providing the level of protection intended by the regulation and that
an exemption from III.G.2 based on this OMA cannot be granted for Fire
Zone 38A.
3.15 Fire Area TBL-5--Turbine Building (Fire Zone 43A--South End,
Elevation 36'-9'')
3.15.1 Fire Prevention
The licensee stated that the fire loading in this area is low and
that the fixed combustibles are paper, MCC switchgear, rubber, wood,
plastic, cable insulation, and incident materials and that transient
combustibles consist of lube oil, solvent, grease, cleaning materials,
and wood. The licensee also stated that the ignition sources in the
area consist of cables, junction boxes, exciter switchgear,
transformers, and electrical cabinets.
3.15.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 43A has an automatic wet-pipe
sprinkler system installed throughout the zone but does not have an
automatic fire detection system installed. The licensee also stated
that the fire suppression system was designed and installed in
accordance with NFPA 13, 1983 Edition.
3.15.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 43A has a ceiling height of
approximately 97'-0'' (See TABLE RAI-GEN-17 of the licensee's May 4,
2010 letter, ML101320263) and an approximate floor area of 7,725 square
feet. The licensee stated that cable AQ7-WF6 for the 31 SW strainer is
routed through Fire Zone 43A in a tray located approximately 7.4 feet
above the floor. The licensee also stated that ignition sources located
less than 20 feet horizontally from the cable consist of cables and 2
electrical cabinets. According to the licensee, the electrical cabinets
are separated from the cable by approximately 1 foot horizontally. The
licensee also stated that the anticipated fire is a slow developing
cable fire located in the cable trays. As discussed in Section 3.0
above, the licensee did not identify any separation between credited
and redundant trains of equipment.
3.15.4 OMAs Credited for a Fire in Fire Area TBL-5 (Fire Zone 43A)
3.15.4.1 OMA 25--Locally Manually Backwash SW Pump Strainer,
as Required, if Power to Strainer Associated With Selected SW Pump Is
Lost
The licensee stated that the need to periodically backwash a
selected SW strainer is variable depending on ultimate heat sink
conditions and other factors and that the diagnostic indicator to
perform the OMA is based on operator rounds monitoring pressure across
SW strainers.
In the event that a fire occurs and causes an increase in SW pump
strainer differential pressure or a loss of power to the strainer
associated with the selected SW pump, the licensee stated that OMA
25 is available to restore this function by locally manually
performing a SW pump strainer backwash. In an inspection report dated
July 11, 2011 (ML111920339), NRC inspectors identified that this OMA
was inappropriate because it was too complex and beyond the limited
scope of an OMA to achieve and maintain post-fire hot shutdown.
Therefore, the NRC staff finds that it is inappropriate to approve this
OMA.
3.15.5 Conclusion for Fire Area TBL-5 (Fire Zone 43A)
Although Fire Zone 43A has an automatic wet-pipe sprinkler system
installed, OMA 25 is not acceptable, Fire Zone 43A lacks
automatic fire detection, and the licensee did not provide details
regarding any discernable separation between the credited and redundant
equipment, and clear and direct procedures that instruct operators to
proactively perform the OMAs, so it is not clear that at least one
train of equipment would remain free of fire damage during or following
a fire event. Therefore, the NRC staff finds that the defense-in-depth
is insufficient to demonstrate reasonable assurance that safe shutdown
can be achieved for a fire in Fire Zone 43A and finds that OMA
25 is unacceptable for the purpose of providing the level of
protection intended by the regulation and that an exemption from
III.G.2 based on this OMA cannot be granted for Fire Zone 43A.
3.16 Fire Area TBL-5--Turbine Building (Fire Zone 44A--South End of
Heater Bay, Elevation 36'-9'')
3.16.1 Fire Prevention
The licensee stated that the fire loading in this area is low and
that the fixed combustibles are a flammable liquid cabinet, cellulose,
rubber, wood, plastic, cable insulation, and incident materials and
that transient combustibles consist of lube oil, solvent, grease,
cleaning materials, and wood. The licensee also stated that the
ignition sources in the area consist of cables, junction boxes, a dry
transformer, and electrical cabinets.
3.16.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 44A does not have a fire
detection or automatic suppression system installed.
3.16.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 44A has a ceiling height of
approximately 29'-0'' and an approximate floor area of 5,625 square
feet. The licensee stated that cable AQ7-WF6 for the 31 SW strainer is
routed through Fire Zone 44A in a tray located approximately 7.4 feet
above the floor. The licensee also stated that ignition sources located
less than 20 feet horizontally from the cable consist of cables, an
MCC, 6.9 kV switchgear, and electrical cabinets. The licensee also
stated that the anticipated fire is a slow developing cable fire
located in the cable trays. As discussed in Section 3.0 above, the
licensee did not identify any separation between credited and redundant
trains of equipment.
3.16.4 OMAs Credited for a Fire in Fire Area TBL-5 (Fire Zone 44A)
3.16.4.1 OMA 25--Locally Manually Backwash SW Pump Strainer,
as Required, if Power to Strainer Associated With Selected SW Pump Is
Lost
The licensee stated that the need to periodically backwash a
selected SW strainer is variable depending on ultimate heat sink
conditions and other factors and that the diagnostic indicator to
perform the OMA is based on operator rounds monitoring pressure across
SW strainers.
In the event that a fire occurs and causes an increase in SW pump
strainer differential pressure or a loss of power to the strainer
associated with the selected SW pump, the licensee stated that OMA
25 is available to restore this function by locally manually
performing a SW pump strainer backwash. In an inspection report dated
July 11, 2011 (ML111920339), NRC inspectors identified that this OMA
was inappropriate because it was too complex and beyond the limited
scope of an OMA to achieve and maintain post-fire hot shutdown.
Therefore, the NRC staff finds that it is inappropriate to approve this
OMA.
[[Page 8920]]
3.16.5 Conclusion for Fire Area TBL-5 (Fire Zone 44A)
Since OMA 25 is unacceptable and Fire Zone 44A lacks fire
detection and automatic suppression and the licensee did not provide
details regarding any discernable separation between the credited and
redundant equipment and clear and direct procedures that instruct
operators to proactively perform the OMA, it is not clear that at least
one train of equipment would remain free of fire damage during or
following a fire event. Therefore, the NRC staff finds that the
defense-in-depth is insufficient to demonstrate reasonable assurance
that safe shutdown can be achieved for a fire in Fire Zone 44A and
finds that OMA 25 is unacceptable for the purpose of providing
the level of protection intended by the regulation and that an
exemption from III.G.2 based on this OMA cannot be granted for Fire
Zone 44A.
3.17 Fire Area TBL-5--Turbine Building (Fire Zone 52A--Chemical
Addition Area, Elevation 32'-6'' of AFW Bldg)
3.17.1 Fire Prevention
The licensee stated that the fire loading in this area is low and
that the fixed combustibles are cable insulation, cellulose barrels,
and rubber hose and that transient combustibles consist of lube oil,
solvent, grease, cleaning materials, and wood. The licensee also stated
that the ignition sources in the area consist of motors, compressors,
and a water heater.
3.17.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 52A does not have a fire
detection or automatic suppression system installed.
3.17.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 52A has a ceiling height of
approximately 8'-6'' and an approximate floor area of 1,254 square
feet. The licensee stated that cable JB1-X32/1 for valve FCV-1121
(recirculation flow for the 31 AFW pump) is located in Fire Zone 52A in
rigid steel conduit. The licensee also stated that ignition sources
located less than 20 feet horizontally from the cable consist of
cables, 2 motors, and 2 electrical cabinets. According to the licensee,
the motors are separated from the cable by approximately 13.2 feet
horizontally and the two electrical cabinets are separated from the
cable by approximately 6.3 feet horizontally.
The licensee stated that cable K45-YM3 for valves FCV-406A and FCV-
406B (31 AFW pump discharge to 31 SG and 32 SG) is located in Fire Zone
52A in rigid steel conduit. The licensee also stated that ignition
sources located less than 20 feet horizontally from the cables consist
of cables, 2 motors, and 2 electrical cabinets. According to the
licensee, the motors are separated from the cables by approximately
13.2 feet horizontally and the two electrical cabinets are separated
from the cables by approximately 6.3 feet horizontally.
As discussed in Section 3.0 above, the licensee did not identify
any separation between credited and redundant trains of equipment.
3.17.4 OMAs Credited for a Fire in Fire Area TBL-5 (Fire Zone 52A)
3.17.4.1 OMA 23--Locally Operate Bypass Valve for FCV-1121 AFW
Pump Recirculation Valve During Pump Startup
If a fire were to occur and cause a loss of CCR control or
indication of FCV-1121 or cause the valve to close and all AFW flow
control valves FCV-406A through 406D fail closed, the licensee stated
that OMA 23 is available to restore this function by locally
operating the bypass valve for FCV-1121 during pump startup. If OMA
23 becomes necessary, the licensee stated that they have
assumed a 4.5-minute diagnosis period and that the required time to
perform the action is 8 minutes while the time available is 30 minutes,
which provides 17.5 minutes of margin.
3.17.4.2 OMA 24--Locally Operate FCV-406A and 406B To Control
AFW Flow to SGs
If a fire were to occur and cause a loss of CCR control or
indication of FCV-1121 or cause the valve to close and all AFW flow
control valves FCV-406A through 406D fail closed, the licensee stated
that OMA 24 is available to restore this function by locally
operating valves FCV-406A and FCV-406B to control AFW flow to the SGs.
If OMA 24 becomes necessary, the licensee stated that they
have assumed a 4.5-minute diagnosis period and that the required time
to perform the action is 17 minutes while the time available is 30
minutes, which provides 8.5 minutes of margin.
3.17.5 Conclusion for Fire Area TBL-5 (Fire Zone 52A)
Although there is 17.5 minutes of margin and 8.5 minutes of margin
available for OMAs 23 and 24, respectively, Fire Zone
52A lacks fire detection and automatic suppression, and the licensee
did not provide details regarding any discernable separation between
the credited and redundant equipment and clear and direct procedures
that instruct operators to proactively perform the OMAs so it is not
clear that at least one train of equipment would remain free of fire
damage during or following a fire event. The NRC staff finds that OMA
24 has insufficient available time margin to allow for
reliable performance considering the potential variables as discussed
in NUREG-1852. Therefore, the NRC staff finds that the defense-in-depth
is insufficient to demonstrate reasonable assurance that safe shutdown
can be achieved for a fire in Fire Zone 52A and finds that an exemption
from III.G.2 based on these OMAs cannot be granted for Fire Zone 52A.
3.18 Fire Area TBL-5--Turbine Building (Fire Zone 54A--Main Boiler
Feedwater Regulator Area, Elevation 18'-6'' of AFW Bldg)
3.18.1 Fire Prevention
The licensee stated that the fire loading in this area is low and
that the fixed combustibles are cable insulation, incidental material,
and a flammable liquid cabinet and that transient combustibles consist
of lube oil, solvent, grease, cleaning materials, and wood. The
licensee also stated that the ignition sources in the area consist of
cables, motors, junction boxes, and an electrical cabinet.
3.18.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 54A does not have a fire
detection or automatic suppression system installed.
3.18.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 54A has a ceiling height of
approximately 70' and an approximate floor area of 1,088 square feet.
The licensee stated that cable K45-YM3 for valves FCV-406A and FCV-406B
are located in Fire Zone 54A in rigid steel conduit. As discussed in
Section 3.0 above, the licensee did not identify any separation between
credited and redundant trains of equipment.
3.18.4 OMAs Credited for a Fire in Fire Area TBL-5 (Fire Zone 54A)
3.18.4.1 OMA 24--Locally Operate FCV-406A and 406B To Control
AFW Flow to SGs
If a fire were to occur and cause a loss of CCR control or
indication of FCV-1121 or cause the valve to close and all AFW flow
control valves FCV-406A through 406D fail closed, the licensee
[[Page 8921]]
stated that OMA 24 is available to restore this function by
locally operating valves FCV-406A and FCV-406B to control AFW flow to
the SGs. If OMA 24 becomes necessary, the licensee stated that
they have assumed a 4.5-minute diagnosis period and that the required
time to perform the action is 17 minutes while the time available is 30
minutes, which provides 8.5 minutes of margin.
3.18.5 Conclusion for Fire Area TBL-5 (Fire Zone 54A)
Although there is 8.5 minutes of margin available for OMA
24, Fire Zone 54A lacks fire detection and automatic fire
suppression, and the licensee did not provide details regarding any
discernable separation between the credited and redundant equipment and
clear and direct procedures that instruct operators to proactively
perform the OMAs so it is not clear that at least one train of
equipment would remain free of fire damage during or following a fire
event. The NRC staff finds that OMA 24 has insufficient
available time margin to allow for reliable performance considering the
potential variables as discussed in NUREG-1852. Therefore, the NRC
staff finds that the defense-in-depth is insufficient to demonstrate
reasonable assurance that safe shutdown can be achieved for a fire in
Fire Zone 54A and finds that an exemption from III.G.2 based on this
OMA cannot be granted for Fire Zone 54A.
3.19 Fire Area YARD-7--Exterior Yard (Fire Zone 22--Screenwell Area)
3.19.1 Fire Prevention
The licensee stated that the fire loading in this area is low and
that the fixed combustibles are cable insulation, MCC switchgear,
plastic, and incidental materials and that transient combustibles
consist of lube oil, solvent, grease, cleaning materials, and wood. The
licensee also stated that the ignition sources in the area consist of
cables, a junction box, a transformer, motors, pumps, and an electrical
cabinet.
3.19.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 22 has an area-wide,
photoelectric smoke detection system that was designed and installed in
accordance with NFPA 72E, 1987 Edition but does not have an automatic
fire suppression system installed.
3.19.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 22 has an approximate floor area
of 784 square feet. Service water pumps 31, 32, 33, 34, 35, and 36,
pump discharge strainers 31-36, and their power cables are located in
the metal enclosure that comprises this fire zone. Backup service water
pumps 37, 38, and 39 are located over 100 feet away on the plant
discharge canal with negligible fixed combustibles between the two
groups of pumps. Although it is unlikely due to the low fire loading, a
fire in this fire zone could potentially disable service water pumps
31-36, which would render the three emergency diesel generators
inoperable due to lack of cooling water, along with other safe shutdown
equipment that requires cooling water. The licensee stated that in the
case of a loss of offsite power in conjunction with the fire in Fire
Zone 22, they could perform an OMA to start the ARDG and energize
backup service water pump 38 to provide cooling water as needed. As
discussed in Section 3.0 above, the licensee did not identify any
separation between credited and redundant trains of equipment.
3.19.4 OMAs Credited for a Fire in Fire Area YARD-7 (Fire Zone 22)
3.19.4.1 OMA 26--Locally Start ARDG To Supply MCC 312A in
Support of the Use of SW Pump 38
In the event that a fire occurs and causes a loss of CCR control or
indication for all SW pumps, the licensee stated that OMA 26
is available to restore this function by locally starting the ARDG
(which is air-cooled) to supply MCC 312A in order to energize the 38
service water pump. If OMA 26 becomes necessary, the licensee
stated that they have assumed a less than 1-minute diagnosis period and
that the required time to perform the action is 25 minutes while the
time available is greater than 60 minutes, which provides 35 minutes of
margin. The NRC staff notes that this is equivalent to implementing an
alternate safe shutdown system in accordance with III.G.3 and does not
qualify for a III.G.2 exemption.
3.19.4.2 OMA 27--Locally Manually Backwash SW Pump Strainer,
as Required, if Power to Strainer Associated With Selected SW Pump Is
Lost
The licensee stated that the need to periodically backwash a
selected SW strainer is variable depending on ultimate heat sink
conditions and other factors and that the diagnostic indicator to
perform the OMA is based on operator rounds monitoring pressure across
SW strainers.
In the event that a fire occurs and causes an increase in SW pump
strainer differential pressure or a loss of power to the strainer
associated with the selected SW pump, the licensee stated that OMA
25 is available to restore this function by locally manually
performing a SW pump strainer backwash. In an inspection report dated
July 11, 2011 (ML111920339), NRC inspectors identified that this OMA
was inappropriate because it was too complex and beyond the limited
scope of an OMA to achieve and maintain post-fire hot shutdown.
Therefore, the NRC staff finds that it is inappropriate to approve this
OMA.
3.19.5 Conclusion for Fire Area YARD-7 (Fire Zone 22)
Since OMA 26 is a III.G.3 solution which does not qualify
for a III.G.2 exemption, and the NRC staff has determined that OMA
27 is an inappropriate OMA, and Fire Zone 22 lacks automatic
fire suppression and the licensee did not provide details regarding any
discernable separation between the credited and redundant equipment, it
is not clear that at least one train of equipment would remain free of
fire damage during or following a fire event. Therefore, the NRC staff
finds that the defense-in-depth is insufficient to demonstrate
reasonable assurance that safe shutdown can be achieved for a fire in
Fire Zone 22 and finds that an exemption from III.G.2 based on these
OMAs cannot be granted for Fire Zone 22. The NRC previously granted an
exemption for Fire Zone 22 dated January 7, 1987 (ML003779008), but
that exemption was primarily associated with the use of the IP3
Alternate Safe Shutdown System. The IP3 Alternate Safe Shutdown System
was not evaluated here as the licensee only requested consideration for
the OMAs.
3.20 Fire Area YARD-7--Exterior Yard (Fire Zone 222--Backup Service
Water Pit)
3.20.1 Fire Prevention
The licensee stated that the fire loading in this area is low and
that the fixed combustibles are cable insulation and that there are no
transient combustibles. The licensee also stated that the ignition
sources in the area consist of motors and pumps.
3.20.2 Detection, Control, and Extinguishment
The licensee stated that Fire Zone 222 does not have a fire
detection or automatic fire suppression system installed.
[[Page 8922]]
3.20.3 Preservation of Safe Shutdown Capability
The licensee stated that Fire Zone 222 is an open outdoor area. The
licensee stated that cables C2B-XD6 and C2B-XD6/1 for the 38 SW pump
are routed through Fire Zone 222 in conduit located approximately 13
feet above the floor. The licensee also stated that ignition sources
located less than 20 feet horizontally from the cables consist of
cables and a temporary yard power station. According to the licensee,
the temporary yard power station is separated from the cables by
approximately 18 feet horizontally.
The licensee also stated that cables MY1-PY1 and PY1-XV2 for the 38
SW strainer are routed through Fire Zone 222. The licensee also stated
that ignition sources located less than 20 feet horizontally from the
cables consist of cables and three motors. According to the licensee,
the motors are separated from the cables by approximately 13.2 feet
horizontally.
As discussed in Section 3.0 above, the licensee did not identify
any separation between credited and redundant trains of equipment.
3.20.4 OMAs Credited for a Fire in Fire Area YARD-7 (Fire Zone 222)
3.20.4.1 OMA 27--Locally Manually Backwash SW Pump Strainer,
as Required, if Power to Strainer Associated With Selected SW Pump Is
Lost
The licensee stated that the need to periodically backwash a
selected SW strainer is variable depending on ultimate heat sink
conditions and other factors and that the diagnostic indicator to
perform the OMA is based on operator rounds monitoring pressure across
SW strainers.
In the event that a fire occurs and causes an increase in SW pump
strainer differential pressure or a loss of power to the strainer
associated with the selected SW pump, the licensee stated that OMA
25 is available to restore this function by locally manually
performing a SW pump strainer backwash. In an inspection report dated
July 11, 2011 (ML111920339), NRC inspectors identified that this OMA
was inappropriate because it was too complex and beyond the limited
scope of an OMA to achieve and maintain post-fire hot shutdown.
Therefore, the NRC staff finds that it is inappropriate to approve this
OMA.
3.20.5 Conclusion for Fire Area YARD-7 (Fire Zone 222)
Since Fire Zone 222 lacks fire detection and automatic suppression
and the licensee did not provide details regarding any discernable
separation between the credited and redundant equipment, it is not
clear that at least one train of equipment would remain free of fire
damage during or following a fire event. The NRC staff has also found
that the use of OMA 27 is inappropriate. Therefore, the NRC
staff finds that the defense-in-depth is insufficient to demonstrate
reasonable assurance that safe shutdown can be achieved for a fire in
Fire Zone 222 and finds that OMA 27 is unacceptable for the
purpose of providing the level of protection intended by the regulation
and that an exemption from III.G.2 based on this OMA cannot be granted
for Fire Zone 222.
4.0 Feasibility and Reliability of the Operator Manual Actions
Based on Section 3.0 above, several areas where OMAs are credited
were found acceptable. The OMAs credited in those areas were then
evaluated for feasibility and reliability. This analysis postulates
that OMAs may be necessary to assure SSD capability in addition to the
traditional fire protection features described above. NUREG-1852,
``Demonstrating the Feasibility and Reliability of Operator Manual
Actions in Response to Fire,'' provides criteria and associated
technical bases for evaluating the feasibility and reliability of post-
fire OMAs in nuclear power plants. The following provides the
licensee's justification for the OMAs specified in this exemption.
4.1 Bases for Establishing Feasibility
The licensee's analysis addresses factors such as environmental
concerns, equipment functionality and accessibility, available
indications, communications, portable equipment, personnel protection
equipment, procedures and training, and staffing and demonstrations. In
its submittals, the licensee stated that environmental factors such as
radiation, lighting, temperature, humidity, smoke, toxic gas, noise,
and fire suppression discharge were evaluated and found to not
represent a negative impact on the operators' abilities to complete the
OMAs. The licensee stated that normal radiation conditions within the
areas of concern will not be adversely affected by the fire and
subsequent spurious equipment operation. The licensee also confirmed
that each of the OMA locations addressed by this exemption are provided
with emergency lighting that illuminates both the potential egress
paths and the component requiring OMA manipulation.
The licensee also confirmed that temperature and humidity
conditions will not challenge the operators performing the OMAs.
Additionally, the licensee indicated that heat and smoke or gas
generation from a fire will not impact the operator performing the
OMAs. For those specific cases in which it is necessary to reenter the
fire area no less than 1 hour after the postulated fire event, the
licensee stated that sufficient time is available to initiate smoke/
heat venting through fixed ventilation systems and augmented by
portable smoke ejectors, consistent with the Pre-Fire Plans, to ensure
operator habitability to implement the necessary OMAs. In addition, the
licensee stated that pre-staged self-contained breathing apparatus
(SCBA), sufficient to equip the full operating crew, are available for
deployment in response to post-fire environmental conditions.
The licensee stated that equipment credited for implementation of
OMAs was reviewed to ensure it is accessible, available, and not
damaged by the affects of the fire. Where ladders are required for
access to components to perform OMAs, appropriate ladders are staged in
accordance with plant procedures and the presence of these ladders is
verified periodically in accordance with plant surveillance procedures.
Any tools that are required in support of post-fire hot shutdown OMAs
are pre-staged at the locations where they would be used. These consist
of common tools such as wrenches, banding cutters, and pliers. Where
special tools/equipment are required, the licensee stated that they are
designated for post-fire cold shutdown repairs, and the necessary tools
and supplies are pre-staged in designated locations. The staging of
necessary tools is confirmed via periodic surveillance.
In addition, the licensee indicates that procedures are in place,
in the form of fire response procedures, to ensure that clear and
accessible instructions on how to perform the manual actions are
available to the operators. The licensee stated that all of the
requested OMAs are directed by plant procedures, and the operators are
trained in the use of the procedures. Specifically, the licensee stated
that post-fire operator manual actions are clearly defined in
procedures 3-ONOP-FP-001 and 3-AOP-SSD-1. The OMAs required for the
III.G.2 fire areas are directed by Off-Normal Operating Procedure 3-
ONOP-FP-001. Where CCR controls and indications are not assured to be
reliably operable, the licensee stated that sufficiently detailed
guidance is provided in procedure 3-AOP-SSD-1 to
[[Page 8923]]
direct the operators to an alternate component or operating method that
is assured to be available and viable for the specific fire scenario
under consideration. Initial and periodic requalification operator
training is provided on these procedures, consistent with standard
licensed and non-licensed operator training programs.
The licensee stated that key diagnostic instrumentation is expected
to remain available in the CCR to alert operators to implement the
contingency OMAs as credited in the IP3 Appendix R SSD Analysis. Key
indicators that trigger the need for local operator intervention for
the credited set of OMAs include not only the RCS and secondary system
instrumentation, but also the failure of components to respond or
reliably indicate status in the CCR. The licensee further stated that
based on field notes compiled from simulator exercises in which
bounding fire area scenarios were modeled, the available CCR
instruments and indicators, combined with operator response in
accordance with Emergency Operating Procedures (EOPs), AOPs, fire SSD
procedures, and other supporting procedures, are sufficient to ensure
timely diagnosis of conditions requiring the dispatch of operator(s) to
perform the credited OMAs outside the CCR.
With regard to communications, the licensee stated that reliance is
placed on radios for communication between plant operators during a
post-fire shutdown event. Radio repeaters are located outside the
protected area and are not subject to disruption caused by fire events
within the protected area. The repeaters are also equipped with
uninterruptible power supplies to ensure continued operation in the
event of the loss of normal power to the buildings in which they are
located. Field verifications of radio system functionality have
validated that communications between the designated control and
monitoring locations are feasible and reliable.
The licensee stated that the manual action sequences in all of the
Section III.G.2 areas are considered to be bounded by the sequences
represented by alternate shutdown (Section III.G.3) Fire Area A. With
regard to staffing, the licensee stated that timed field walkthroughs
of Abnormal Operating Procedure 3-AOP-SSD-1 have been performed to
validate that the number of operators available on the watch staff (7)
can safely accomplish all required actions within the required time
period to meet Appendix R SSD performance goals. The licensee stated
that the broad set of operator manual actions required in implementing
alternate shutdown procedure 3-AOP-SSD-1 bounds the smaller set of
manual actions credited for coping with III.G.2 fire area scenarios and
that most OMAs required for the III.G.2 fire areas are directed by Off-
Normal Operating Procedure 3-ONOP-FP-001.
Additionally, the licensee stated that post-fire OMAs have been
validated through timed operator walkthroughs, using as the basis an
enveloping scenario addressed by 3-AOP-SSD-1. When utilizing 3-AOP-SSD-
1, the most challenging set of local manual operator actions (number of
actions and time sensitivity of actions) is presented to the operations
shift crew, and this set of actions is considered to adequately bound
the limited set of manual actions that are credited in 3-ONOP-FP-001.
The licensee states that the timed walkthroughs of 3-AOP-SSD-1 have
consistently demonstrated that the key SSD tasks (e.g., restoration of
RCS makeup; restoration of AFW to SGs; mitigation of key potential
spurious actuation concerns) can be accomplished in a timely manner to
meet the Appendix R SSD performance goals. The licensee further states
that in addition to the validation of key OMAs credited in alternate
SSD procedure 3-AOP-SSD-1, the plant simulator was utilized to perform
evaluations of bounding III.G.2 fire scenarios, and based on the field
notes compiled from these exercises, there is reasonable assurance that
conditions requiring the implementation of the identified OMAs can be
identified and mitigated in a sufficiently timely manner to ensure
Appendix R performance goals are met.
4.2 Feasibility
The licensee's analysis demonstrates that, with exceptions, the
OMAs can be diagnosed and executed within the amount of time available
to complete them. The licensee's analysis also demonstrates that
various factors, as discussed above, have been considered to address
uncertainties in estimating the time available. The licensee stated
that the credited OMAs have been demonstrated to be feasible through
timed evolutions performed using a combination of simulator drills and
dispatch of operators to simulate performance of the OMAs within the
physical plant. In most cases, the OMAs are completed, with margin
remaining, within the time constraints established by the supporting
SSD thermal-hydraulic analyses. The licensee stated that the time
values have been shown to be consistently achievable, and the
operations resource demand required to support any one of the fire area
scenarios is a fraction of the 7-operator complement available to
support a PFSSD scenario.
The following table summarizes the ``required time'' versus
``available time'' for each OMA. The indicated ``required time'' is the
time needed to complete all actions that may be required as a result of
fire in each of the identified fire areas and includes diagnosis time,
implementation time, and uncertainty time. The indicated ``available
time'' is the time by which the action must be completed in order to
meet the assumptions in plant analyses. The NRC staff finds that the
required time to perform the actions is reasonable as the licensee has
verified these times in simulator scenarios and by simulating
performance in the plant. Where reentry to a fire area is required to
perform an OMA, a 60-minute waiting period is also included in the
required time and the diagnosis period for these instances was assumed
to occur concurrent with the waiting period. Finally, the times noted
below should be considered with the understanding that the manual
actions are a fall back in the unlikely event that the fire protection
defense-in-depth features are insufficient.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Required Available
Fire area Fire zones \1\ OMA ID OMA Summary time (min) Available margin
\2\ \3\ time (min) (min)
--------------------------------------------------------------------------------------------------------------------------------------------------------
AFW-6................................... 23......................... 1 Locally start 33 AFW Pump via 17.5 30 12.5
operation of the Bus 6A circuit
breaker.
--------------------------------------------------------------------------------------------------------------------------------------------------------
ETN-4{1{time} .......................... 7A......................... 2 Swap 32 Component Cooling Water 34 >60 26
(CCW) pump to alternate power
supply or align city water to
charging pumps.
7A......................... 3 Operate 480V Bus 3A breaker 11.5 30 18.5
locally to start 31 AFW pump.
[[Page 8924]]
7A......................... 4 Locally operate Flow Control 12.5 30 17.5
Valve (FCV)-1121 in support of
use of 31 AFW pump.
60A........................ 5 Operate HCV-1118 manually to 21.5 30 \4\ 8.5
control 32 AFW pump.
7A, 60A.................... 6 Align Appendix R Diesel 50 75 \5\ 25
Generator (ARDG) to 480V Buses
2A, 3A, 5A, and 312.
7A, 60A.................... 7 Swap 31 or 32 charging pump to 38 75 37
alternate power supply.
7A, 60A.................... 8 Locally operate FCV-405B, FCV- 21.5 30 \4\ 8.5
405D, or FCV-406B to control
AFW flow to Steam Generators
(SGs).
60A........................ 9 Locally open valve 227 to 69 75 \4\ 6
establish charging [previously
``CVCS'] makeup flowpath to
Reactor Coolant System (RCS).
60a........................ 10 Locally close valve LCV-112C and 71 75 \4\ 4
open valve 288 to align
charging pump suction to the
Refueling Water Storage Tank
(RWST).
60A........................ 11 Locally operate PCV-1139 to 21.5 30 \4\ 8.5
ensure steam supply to 32 AFW
pump.
60A........................ 12 Locally operate PCV-1310A and 21.5 30 \4\ 8.5
PCV-1310B to ensure steam
supply to 32 AFW pump.
60A........................ 13 Locally manually perform Service >75 >60 *
Water (SW) pump strainer
backwash as required.
--------------------------------------------------------------------------------------------------------------------------------------------------------
ETN-4{3{time} .......................... 73A........................ 14 Operate HCV-1118 manually to 21.5 30 \4\ 8.5
control 32 AFW pump.
........................... 15 Locally operate PCV-1139 to 21.5 30 \4\ 8.5
ensure steam supply to 32 AFW
pump.
........................... 16 Locally operate 32 PCV-1310A, 21.5 30 \4\ 8.5
PCV-1310B to ensure steam
supply to 32 AFW pump.
........................... 17 Locally operate FCV-405C and FCV- 21.5 30 \4\ 8.5
405D to control AFW flow to SG.
--------------------------------------------------------------------------------------------------------------------------------------------------------
PAB-2{3{time} .......................... 6.......................... 18 Locally close valve LCV-112C and 71 75 \4\ 4
open valve 228 to align
charging pump suction path to
RWST.
--------------------------------------------------------------------------------------------------------------------------------------------------------
PAB-2{5{time} .......................... 17A, 19A, 58A,............. 19 Locally close supply breaker for 37 75 38
32 Charging Pump [previously
``CVCS''] Pump.
17A, 19A, 58A.............. 20 Locally control 32 charging 39 75 36
[previously ``CVCS''] pumps
using scoop tube positioner.
59A........................ 21 Open bypass valve 227 to 69 75 \4\ 6
establish charging flowpath to
RCS around potentially failed
closed HCV-142.
17A, 20A, 27a, 30A......... 22 Locally Close LCV-112C and open 71 75 \4\ 4
bypass valve 288 to establish
flowpath from RWST to charging
pump suction.
--------------------------------------------------------------------------------------------------------------------------------------------------------
TBL-5................................... 52A........................ 23 Locally operate [bypass valve 12.5 30 17.5
for] FCV-1121 AFW pump
recirculation valve during pump
startup.
52A, 54A................... 24 Locally operate FCV-406A and FCV- 21.5 30 \4\ 8.5
406B to control AFW flow to SGs.
37A, 38A, 43A, 44A......... 25 Locally/manually backwash SW >75 >60 *
pump strainer as required if
power to strainer associated
with selected SW pump is lost
(use one of STR PMP-31 through
STR PMP-36).
--------------------------------------------------------------------------------------------------------------------------------------------------------
YARD-7.................................. 22......................... 26 Locally start ARDG to supply 25 >60 \5\ >35
Motor Control Center (MCC) 312A
in support of the use of SW
pump 38.
[[Page 8925]]
22, 222.................... 27 Locally/manually backwash SW >75 >60 *
Pump strainer as required if
power to strainer associated
with selected SW pump is lost.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Not acceptable.
\1\ Fire Areas are areas of fire origin; Indicated Fire Zones contain the cables or equipment whose damage due to fire may require implementation of the
OMAs.
\2\ Operator Action ID designators (1, 2, 3 etc.) were assigned by the NRR reviewer.
\3\ Total of simulator-based diagnosis was added to the field-based time to travel to the OMA location, complete the OMA, confirm the action, and notify
the CCR of completion as well as the 60-minute waiting period as discussed above.
\4\ OMAs found to be feasible but unreliable.
\5\ OMAs associated with III.G.3.
4.3 Reliability
As stated in NUREG-1852, for a feasible action to be performed
reliably, it should be shown that there is adequate time available to
account for uncertainties not only in estimates of the time available,
but also in estimates of how long it takes to diagnose and execute the
OMAs (e.g., as based, at least in part, on a plant demonstration of the
action under non-fire conditions). To confirm reliability, for each
fire area having the potential to initiate the need for an OMA, the
licensee considered uncertainties associated with estimating how long
it takes to diagnose and execute operator manual actions.
Where the licensee demonstrated that adequate margin was available,
the required completion times noted in the table above provide
reasonable assurance that the OMAs can reliably be performed under a
wide range of conceivable conditions by different plant crews because
the completion times, in conjunction with the available time margins
associated with each action and other installed fire protection
features, account for sources of uncertainty such as variations in fire
and plant conditions, factors unable to be recreated in demonstrations
and human-centered factors. As noted in the table above, several of the
OMAs included in this review were found to be reliable because there is
adequate time available to account for uncertainties not only in
estimates of the time available, but also in estimates of how long it
takes to diagnose a fire and execute the OMAs (e.g., as based, at least
in part, on a plant demonstration of the actions under non-fire
conditions). Other OMAs were determined to be feasible but not reliable
since only nominal margin is available to complete them. Those OMAs
found to be feasible but unreliable are those indicated by footnote
4 to the table above.
4.4 Summary of Defense-in-Depth and Operator Manual Actions
In summary, the defense-in-depth concept for a fire in the fire
areas included in the table below provides a level of safety that
results in the unlikely occurrence of fires, rapid detection, control
and extinguishment of fires that do occur and the protection of
structures, systems and components important to safety. For these
particular fire zones and the OMAs credited in them and found
acceptable in Sections 3.0 and 4.0 above, the licensee has provided
preventative and protective measures in addition to feasible and
reliable OMAs that together demonstrate the licensee's ability to
preserve or maintain SSD capability in the event of a fire in the
analyzed fire areas. The remaining zones included in the licensee's
request were found to provide an inadequate level of defense-in-depth
or safety margin and as such the requested OMAs for these zones are not
approved for permanent use. The table below summarizes which fire zones
are granted exemptions from III.G.2.
------------------------------------------------------------------------
Area of fire Exemption approved for
Fire zone origin this fire zone
------------------------------------------------------------------------
23............................ AFW-6 Previous exemption
remains valid.
7A............................ ETN-4{1{time} No.
60A........................... ETN-4{1{time} No.
73A........................... ETN-4{3{time} No.
6............................. PAB-2{3{time} No.
17A........................... PAB-2{5{time} No.
19A........................... PAB-2{5{time} No.
20A........................... PAB-2{5{time} No.
27A........................... PAB-2{5{time} No.
30A........................... PAB-2{5{time} No.
58A........................... PAB-2{5{time} Yes.
59A........................... PAB-2{5{time} No.
37A........................... TBL-5 No.
38A........................... TBL-5 No.
43A........................... TBL-5 No.
44A........................... TBL-5 No.
52A........................... TBL-5 No.
54A........................... TBL-5 No.
22............................ YARD-7 No.
222........................... YARD-7 No.
------------------------------------------------------------------------
4.5 Authorized by Law
This exemption would allow IP3 to rely on specific OMAs, as
discussed in Sections 3.0 and 4.0 above, in conjunction with the other
installed fire protection features, to ensure that at least one means
of achieving and maintaining safe shutdown remains available during and
following a postulated fire event, as part of its fire protection
program, in lieu of meeting the requirements specified in III.G.2 for a
fire in the analyzed fire areas. As stated above, 10 CFR 50.12 allows
the NRC to grant exemptions from the requirements of 10 CFR part 50.
The NRC staff has determined that granting of this exemption will not
result in a violation of the Atomic Energy Act of 1954, as amended, or
the Commission's regulations. Therefore, the exemption is authorized by
law.
4.6 No Undue Risk to Public Health and Safety
The underlying purpose of 10 CFR part 50, Appendix R, Section III.G
is to ensure that at least one means of achieving and maintaining safe
shutdown remains available during and following a postulated fire
event. Based on the above, no new accident precursors are created by
the use of the specific OMAs, in conjunction with the other installed
fire protection features, in response to a fire in the analyzed fire
areas. Therefore, the probability of postulated accidents is not
increased. Also based on the above, the consequences of postulated
accidents are not increased. Therefore, there is no undue risk to
public health and safety.
4.7 Consistent With Common Defense and Security
This exemption would allow IP3 to credit the use of the specific
OMAs, in conjunction with the other installed fire protection features,
in response to a fire in the analyzed fire areas, discussed above, in
lieu of meeting the requirements specified in III.G.2. This
[[Page 8926]]
change to the operation of the plant has no relation to security
issues. Therefore, the common defense and security is not diminished by
this exemption.
4.8 Special Circumstances
One of the special circumstances described in 10 CFR
50.12(a)(2)(ii) is that the application of the regulation is not
necessary to achieve the underlying purpose of the rule. The underlying
purpose of 10 CFR Part 50, Appendix R, Section III.G is to ensure that
at least one means of achieving and maintaining safe shutdown remains
available during and following a postulated fire event. While the
licensee does not comply with the explicit requirements of Section
III.G.2, the approved OMAs, in conjunction with the other installed
fire protection features, provide a method to ensure that a train of
equipment necessary to achieve and maintain safe shutdown of the plant
will be available in the event of a fire in these fire zones. The NRC
staff concludes that application of the regulation is not necessary to
achieve the underlying purpose of the rule for the plant configurations
approved in this exemption. Therefore special circumstances exist, as
required by 10 CFR 50.12(a)(2)(ii), that warrant the issuance of this
exemption.
5.0 Conclusion
Based on all of the features of the defense-in-depth concept
discussed for the fire zones listed in Section 4.4 of this exemption,
the NRC staff concludes that the use of specific OMAs found acceptable
in Sections 3.0 and 4.0 of this evaluation, in these particular
instances and in conjunction with the other installed fire protection
features, in lieu of strict compliance with the requirements of
III.G.2, will allow IP3 to meet the underlying purpose of the rule for
those fire zones. The use of other specific OMAs in certain fire zones
were found to be not acceptable, as discussed in Sections 3.0 and 4.0
of this evaluation, and as such, are not approved by this exemption.
Accordingly, the Commission has determined that, pursuant to 10 CFR
50.12(a), the exemption is authorized by law, will not present an undue
risk to the public health and safety, is consistent with the common
defense and security and that special circumstances are present to
warrant issuance of the exemption. Therefore, the Commission hereby
grants Entergy an exemption from the requirements of Section III.G.2 of
Appendix R of 10 CFR part 50, to utilize the OMAs approved above at
IP3.
Pursuant to 10 CFR 51.32, the Commission has determined that the
granting of this exemption will not have a significant effect on the
quality of the human environment (76 FR 74832).
This exemption is effective upon issuance.
Dated at Rockville, Maryland, this first day of February 2012.
For the Nuclear Regulatory Commission.
Michele G. Evans,
Director, Division of Operating Reactor Licensing, Office of Nuclear
Reactor Regulation.
[FR Doc. 2012-3122 Filed 2-14-12; 8:45 am]
BILLING CODE 7590-01-P