Federal Register, Volume 76 Issue 68 (Friday, April 8, 2011)

[Federal Register Volume 76, Number 68 (Friday, April 8, 2011)]
[Notices]
[Pages 19795-19817]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-8405]

-----------------------------------------------------------------------

NUCLEAR REGULATORY COMMISSION

[Docket No. 50-219; NRC-2010-0320]

Exelon Generation Company, LLC; Oyster Creek Nuclear Generating
Station; Exemption

1.0 Background

Exelon Generation Company, LLC (Exelon or the licensee) is the
holder of Facility Operating License No. DPR-16 that authorizes
operation of the Oyster Creek Nuclear Generating Station (Oyster
Creek). 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.
The facility consists of a boiling-water reactor located in Ocean
County, New Jersey.

2.0 Request/Action

Title 10 of the Code of Federal Regulations (10 CFR), part 50,
Section 50.48 requires that nuclear power plants that were licensed
before January 1, 1979, must satisfy the requirements of 10 CFR part
50, Appendix R, Section III.G, ``Fire protection of safe shutdown
capability.'' Oyster Creek was licensed to operate prior to January 1,
1979. As such, the licensee's Fire Protection Program (FPP) must
provide the established level of protection as intended by Section
III.G of 10 CFR part 50, Appendix R.
By letter dated March 3, 2009, ``Request for Exemption from 10 CFR
50, Appendix R, Section III.G, `Fire Protection of Safe Shutdown
Capability (Phase 1)' '' available at Agencywide Documents Access and
Management System (ADAMS), Accession No. ML090630132, and supplemented
by letter dated April 2, 2010, ``Response to Request for Additional
Information Request for Exemption from 10 CFR 50, Appendix R, Section
III.G, `Fire Protection of Safe Shutdown Capability' '' (ML100920370),
the licensee requested an exemption for Oyster Creek from certain
technical requirements of 10 CFR part 50, Appendix R, Section III.G.2
(III.G.2) for the use of operator manual actions (OMAs) in lieu of
meeting the circuit separation and protection requirements contained in
III.G.2 for the following 21 plant Fire Areas: CW-FA-14, OB-FA-9, OB-
FZ-6A, OB-FZ-6B, OB-FZ-8A, OB-FZ-8B, OB-FZ-8C, OB-FZ-10A, RB-FZ-1D, RB-
FZ-1E, RB-FZ-1F3, RB-FZ-1F5, RB-FZ-1G, TB-FA-3A, TB-FA-26, TB-FZ-11B,
TB-FZ-11C, TB-FZ-11D, TB-FZ-11E, TB-FZ-11F, and TB-FZ-11H. These 21
plant areas are the subject of this exemption.

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 has stated
that special circumstances are present in that the application of the
regulation in this particular circumstance is not necessary to achieve
the underlying purpose of the rule, which is consistent with the
language included in 10 CFR 50.12(a)(2)(ii).
In their March 3, 2009, and April 2, 2010, letters, the licensee
discussed financial implications associated with plant modifications
that may be necessary to comply with the regulation. 10 CFR
50.12(a)2(iii) states that if such costs have been shown to be
significantly in excess of those contemplated at the time the
regulation was adopted, or are significantly in excess of those
incurred by others similarly situated, this may be considered a basis
for considering an exemption request. However, financial implications
were not considered in the regulatory review of their request since no
substantiation was provided regarding such financial implications. Even
though no financial substantiation was provided, the licensee did
submit sufficient regulatory basis to support a technical review of
their exemption request in that 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
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 safe shutdown is preserved following a fire event. The
regulation intends for licensees to accomplish this by extending the
concept of defense-in-depth to:
(1) Prevent fires from starting;
(2) Rapidly detect, control, and extinguish promptly those fires
that do occur;
(3) 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 safe shutdown of
the plant.
The stated purpose of 10 CFR part 50, Appendix R, Section III.G.2
(III.G.2) is to ensure that one of the redundant trains necessary to
achieve and maintain hot shutdown conditions remains free of fire
damage in the event of a fire. III.G.2 requires one of the following
means to ensure that a redundant train of safe shutdown 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

[[Page 19796]]

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.
Exelon has requested an exemption from the requirements of III.G.2
for Oyster Creek to the extent that redundant trains of systems
necessary to achieve and maintain hot shutdown are not maintained free
of fire damage in accordance with one of the required means prescribed
in III.G.2.
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. Table 1 lists, in the
order of the fire area of fire origin, the OMAs included in this
review.

Table 1
------------------------------------------------------------------------
Area of fire origin Area name Actions OMA No.
------------------------------------------------------------------------
1 CW-FA-14............... Circulatory Water Manually open 7
Intake. valve (V) V-9-
2099 and V-11-49
and close V-11-
63 and V-11-41.
Manually open V- 12
15-237, throttle
V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52.
------------------------------------------------------------------------
2 OB-FA-9................ Office Building Locally read 2
(Bldg.) Elev. Condensate
23'-6'', 35'- Storage Tank
0'', 46'-6''. level at level
indicator (LI)
LI-424-993 due
to damage to
control circuits.
Manually open V- 12
15-237, throttle
V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52.
------------------------------------------------------------------------
3 OB-FZ-6A............... Office Bldg. Locally read 2
``A'' 480V condensate
Switchgear storage tank
(SWGR) Room (CST) level at
Elev. 23'-6''. LI-424-993 due
to damage to
control circuits.
Use Remote 9
Shutdown Panel
(RSP) to control
equipment: RSP,
Control Rod
Drive (CRD)
Hydraulic Pump
NC08B and 480V
USS 1B2 Incoming
breaker (Operate
USS 1B2/CRD
Transfer Switch
(Partial
initiation) to
``Alternate''
and operate
Control Switches
for USS-1B2 Main
Breaker and B
CRD Pump).
Manually open V- 12
15-237, throttle
V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52.
------------------------------------------------------------------------
4 OB-FZ-6B............... Office Bldg. Manually open V-9- 7
``B'' 480V SWGR 2099 and V-11-49
Room Elev. 23'- and close V-11-
6''. 63 and V-11-41.
Manually open V- 12
15-237, throttle
V-15-30 using
local flow
indicator (FI)
FI-225-2 and
close V-15-52.
------------------------------------------------------------------------
5 OB-FZ-8A............... Office Bldg. Manually open V-9- 7
Reactor 2099 and V-11-49
Recirculation and close V-11-
Motor Generator 63 and V-11-41.
(MG) Set Room
Elev. 23'-6''.
Manually open V- 12
15-237, throttle
V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52.
------------------------------------------------------------------------
6 OB-FZ-8B............... Office Bldg. Manually open V-9- 7
Mechanical 2099 and V-11-49
Equipment Room and close V-11-
Elev. 35'-0''. 63 and V-11-41.
Manually open V- 12
15-237, throttle
V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52.
------------------------------------------------------------------------
7 OB-FZ-8C............... Office Bldg. A/B Locally read 2
Battery Room, Condensate
Tunnel and Storage Tank
Electrical Tray level at LI-424-
Room Elev. 35'- 993 due to
0''. damage to
control circuits.
Manually open V-9- 7
2099 and V-11-49
and close V-11-
63 and V-11-41.
Use Local 8
Shutdown Panels
to control
equipment as
follows: LSP-
1A2, CRD
Hydraulic PP
NC08A and 480V
USS 1A2 Incoming
breaker (Operate
transfer switch
``Alternate''
and operate
Control Switch
for USS-1A2 Main
Breaker 1A2M and
A CRD Pump).
Manually open V- 12
15-237, throttle
V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52.
Trip all five 16
Reactor
Recirculation
Pumps (NG01-A,
NG01-B, NG01-C,
NG01D and
NG01E). Also,
lockout the
4160V breakers
using local
switch.
------------------------------------------------------------------------
8 OB-FZ-10A.............. Office Bldg. Manually open V- 12
Monitor and 15-237, throttle
Change Room Area V-15-30 using
and Operations local flow
Support Area indicator (FI-
Elev. 35'-0'' & 225-2) and close
46'-6''. V-15-52.
------------------------------------------------------------------------
9 RB-FZ-1D............... Reactor Bldg. Manually open V- 12
Elev. 51'-3''. 15-237, throttle
V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52;.
------------------------------------------------------------------------
10 RB-FZ-1E.............. Reactor Building Read CRD local 11
Elev. 23'-6''. flow gauge FI-
225-998.
Manually open V- 12
15-237, throttle
V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52.
------------------------------------------------------------------------

[[Page 19797]]

11 RB-FZ-1F3............. Reactor Bldg. Open Core Spray 13
Northwest Corner System II manual
Elev.-19'-6''. valves V-20-1
and V-20-2 and
close V-20-4.
------------------------------------------------------------------------
12 RB-FZ-1F5............. Reactor Bldg. Manually open V- 12
Torus Room Elev. 15-237, throttle
-19'-6''. V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52.
------------------------------------------------------------------------
13 RB-FZ-1G.............. Reactor Bldg. Read CRD local 11
Shutdown Cooling flow gauge FI-
Room Elev. 38'- 225-998.
0'' & 51'-3''.
Manually open V- 12
15-237, throttle
V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52.
------------------------------------------------------------------------
14 TB-FA-3A.............. Turbine Bldg. Manually open V- 12
4160V Emergency 15-237, throttle
SWGR Vault 1C V-15-30 using
Elev. 23'-6''. local flow
indicator (FI-
225-2) and close
V-15-52.
------------------------------------------------------------------------
15 TB-FA-26.............. Turbine Bldg. Manually trip 1
125V DC Battery 4160V 1D
Room C Elev. 23'- Breakers and
6''. control USS 1B2
and 1B3 480V
Breakers locally
at LSP-1D.
Manually control 3
1B3M Breaker
from LSP-1B3.
Manually re-close 6
motor control
center (MCC)
1B32 Feeder
Breaker at USS
1B3.
Manually open V- 12
15-237, throttle
V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52.
------------------------------------------------------------------------
16 TB-FZ-11B............. Turbine Bldg. Manually trip 1
Lube Oil 4160V 1D
Storage, Breakers and
Purification and control USS 1B2
Pumping Area and 1B3 480V
Elev. 0'-0'', Breakers locally
27'-0'', and 36'- at LSP-1D.
0''.
Locally read 2
Condensate
Storage Tank
level at LI-424-
993.
Manually control 3
1B3M Breaker
from LSP-1B3.
Local Shutdown 4
Panels used to
control
equipment as
follows: LSP-
1B32 Condensate
Transfer Pump 1-
2 (Operate
transfer switch
to ``Alternate''
and operate
Control Switch
for Condensate
Transfer Pump 1-
2).
Manually re-close 6
MCC 1B32 Feeder
Breaker at USS
1B3.
Manually open V- 12
15-237, throttle
V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52.
Trip all five 16
Reactor
Recirculation
Pumps (NG01-A,
NG01-B, NG01-C,
NG01D and
NG01E). Also,
lockout the
4160V breakers
using local
switch.
------------------------------------------------------------------------
17 TB-FZ-11C............. Turbine Bldg. Manually trip 1
SWGR Room 1A and 4160V 1D
1B Elev. 23'-6''. Breakers and
control USS 1B2
and 1B3 480V
Breakers locally
at LSP-1D.
Manually control 3
1B3M Breaker
from LSP-1B3.
Manually re-close 6
MCC 1B32 Feeder
Breaker at USS
1B3.
Manually open V- 12
15-237, throttle
V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52.
------------------------------------------------------------------------
18 TB-FZ-11D............. Turbine Bldg. Manually trip 1
Basement Floor 4160V 1D
South End Elev. Breakers and
3'-6''. control USS 1B2
and 1B3 480V
Breakers locally
at LSP-1D.
Manually control 3
1B3M Breaker
from LSP-1B3.
Local Shutdown 5
Panels are used
to control
equipment as
follows: LSP-
DG2, EDG2 and
its Switchgear
(Operate
transfer
Switches (3
total) to
``Alternate''
and operate
Control Switch
on Diesel Panel
to start diesel).
Manually re-close 6
MCC 1B32 Feeder
Breaker at USS
1B3.
Manually open V- 12
15-237, throttle
V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52.
------------------------------------------------------------------------
19 TB-FZ-11E............. Turbine Bldg. Manually trip 1
Condenser Bay 4160V 1D
Area Elev. 0'- Breakers and
0''. control USS 1B2
and 1B3 480V
Breakers locally
at LSP-1D.
Locally read 2
Condensate
Storage Tank
level at LI-424-
993.
Manually control 3
1B3M Breaker
from LSP-1B3.
Local Shutdown 4
Panels used to
control
equipment as
follows: LSP-
1B32 Condensate
Transfer Pump 1-
2 (Operate
transfer switch
to ``Alternate''
and operate
Control Switch
for Condensate
Transfer Pump 1-
2).

[[Page 19798]]

Local Shutdown 5
Panels are used
to control
equipment as
follows: LSP-
DG2, EDG2 and
its Switchgear
(Operate
transfer
Switches (3
total) to
``Alternate''
and operate
Control Switch
on Diesel Panel
to start diesel).
Manually re-close 6
MCC 1B32 Feeder
Breaker at USS
1B3.
Manually open V- 12
15-237, throttle
V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52.
Trip all five 16
Reactor
Recirculation
Pumps (NG01-A,
NG01-B, NG01-C,
NG01D and NG01E)
Also, lockout
the 4160V
breakers using
the 69 Switch.
------------------------------------------------------------------------
20 TB-FZ-11F............. Turbine Bldg. Manually open V-9- 7
Feedwater Pump 2099 and V-11-49
Room Elev. 0'- and close V-11-
0'' & 3'-6''. 63 and V-11-41.
Manually open V- 12
15-237, throttle
V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52.
------------------------------------------------------------------------
21 TB-FZ-11H............. Turbine Bldg. Manually open V-9- 7
Demineralizer 2099 and V-11-49
Tank and Steam and close V-11-
Jet Air Ejector 63 and V-11-41.
Area Elev. 3'-
6'' & 23'-6''.
Manually open V- 12
15-237, throttle
V-15-30 using
local flow
indicator (FI-
225-2) and close
V-15-52.
------------------------------------------------------------------------

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 April 2, 2010, letter 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. The licensee developed a Fire
Hazards Analysis (FHA) for each fire area or zone identified in its
exemption request. For each fire area or zone, the FHA describes the
physical location and arrangement of equipment, combustible loading,
ignition sources, fire protection features, and proximity of redundant
safe shutdown equipment to in situ hazards and identifies deviations
from fire protection codes and previously approved exemptions. In
addition, for each fire area or zone the licensee's response includes a
tabulation of potential ignition sources as well as the equipment that
may exhibit high energy arcing faults. For each fire area or zone, the
FHA states that the fire protection configuration achieves a level of
protection commensurate with that intended by III.G.2.
The 21 areas or zones identified in the request have
administratively limited combustible fuel loading with fuel sources
consisting primarily of cable insulation and limited floor based
combustibles except areas OB-FZ-6A, OB-FZ-6B, and TB-FZ-11B, which
contain quantities of transformer liquid or lubricating oil.
Combustible fuel loading in most areas is classified as low by the
licensee while Fire Areas OB-FZ-6A, OB-FZ-6B, and TB-FA-26 have been
classified as having moderate combustible fuel loading and TB-FZ-11B
has been classified as having a high combustible fuel loading. In
addition, the licensee has stated that they maintain a robust
administrative program (e.g., hot work permits, fire watches for hot
work, and supervisory controls) to limit and control transient
combustible materials and ignition sources in the areas. The fire areas
included in the exemption are not shop areas so hot work activities are
infrequent and the administrative control programs are in place if hot
work activities do occur.
The licensee also stated that 98% of the Oyster Creek cables are
jacketed with Vulkene, which passes the horizontal flame test of the
Underwriter's Laboratory (UL), therefore reducing the likelihood of the
cables themselves contributing to a fire hazard. Furthermore, the areas
or zones are of noncombustible construction with typical utilities
installed, lighting, ventilation, etc. and 3-hour fire resistance-rated
barriers normally used to provide fire resistive separation between
adjacent fire areas. In some cases, barriers with a fire resistance
rating of less than 3 hours are credited but exemptions have been
approved or the licensee has stated they have performed engineering
evaluations in accordance with Generic Letter 86-10, ``Implementation
of Fire Protection Requirements,'' to demonstrate that the barriers are
sufficient for the hazard. Walls separating rooms and zones within fire
areas are typically constructed of heavy concrete. This
compartmentalization of the areas reduces the likelihood for fire
events in a particular area to spread to or impact other adjacent
areas.
Many fire areas included in this exemption have automatic detection
systems installed, although the licensee indicated that not all systems
are installed in accordance with a recognized standard with regard to
spacing in all areas. In such cases, the licensee has stated that the
detectors are located near equipment such that they are likely to
detect a fire. Upon detecting smoke, the detectors initiate an alarm in
the constantly staffed control room. In addition to the automatic
suppression systems noted below, equipment operators are trained fire
brigade members and may identify and manually suppress or extinguish a
fire using the portable fire extinguishers and manual hose stations
located throughout the fire areas if a fire is identified in its early
stages of growth.
The licensee stated that the postulated fire events that may
require the use of the OMAs would include multiple

[[Page 19799]]

failures of various components or equipment. In most cases, it is
considered unlikely that the sequence of events required to necessitate
the OMAs would fully evolve because of the fire prevention, fire
protection, and physical separation features in place. However, in the
event that the sequence does evolve, the OMAs are available to provide
assurance that safe shutdown can be achieved. For each of the fire
areas included in this exemption, the postulated fire scenarios and
pertinent details are summarized in the table below.
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 CW-FA-14--Circulatory Water Intake

3.1.1 Fire Prevention
The licensee stated that combustible loading is not tracked in this
area since it is an outside area. The licensee also stated that the
primary combustible materials in the area are transformer liquid and
electrical motors; although the amount is not quantified since the area
is open to the atmosphere with no walls or ceiling to contain the heat
or smoke that may be produced during a fire event. Additionally, the
main combustible in this area that could result in the need for the
OMAs is Dow Corning 561 Silicon transformer liquid, which the licensee
states has characteristics that minimize the likelihood of a fire
involving the insulating liquid itself.
3.1.2 Detection, Control, and Extinguishment
CW-FA-14 is not equipped with automatic fire detection or
suppression systems but since it is an outdoor area with no walls or
ceiling, it is not expected that such systems would enhance this
element of defense-in-depth in this area since the area is open to the
atmosphere with no walls or ceiling to contain the heat or smoke that
may be produced during a fire event. However, the licensee stated that
a security tower monitors this area continuously; therefore, any fire
of significance would be detected and responded to appropriately by the
station fire brigade. Manual suppression is also provided by a fire
hydrant and fire hose house located approximately 75 feet from the
principal fire hazards.
3.1.3 Preservation of Safe Shutdown Capability
Since Fire Area CW-FA-14 is an outdoor space with no walls or
ceiling, smoke and heat would not accumulate within the fire area to
cause damage to components remote to the initiating fire or obstruct
operator actions.
3.1.4 OMAs Credited for a Fire in This Area
3.1.4.1 OMA 7--Align the Fire Water System to the Isolation
Condenser
In order for OMA 7 to be necessary, the loss of the ``B''
Train of power would have to occur due to fire damage. Unit Substation
Transformer (USS) 1B3 is located in the outside area on the west side
of the power block on a raised concrete foundation that sits
approximately 5 feet above grade. USS 1B3 is considered as a potential
ignition source as well as its associated adjacent transformer, USS
1A3, which is located approximately 15 feet west of USS 1B3. Both of
these unit substations are located approximately 20 feet from any plant
operating equipment (e.g., circulating water pump motor, etc.).
Additionally, the need to perform this OMA would likely be apparent in
the control room based on the loads that are lost (e.g., control room
ventilation, service water pump, etc.) and a fire at USS 1B3 would be
visible from the security tower monitoring the area.
In the unlikely event that a fire does occur and causes the loss of
USS 1B3 or its associated cables, OMA 7 is available to
manually open V-9-2099 and V-11-49 and close V-11-63 and V-11-41 to
align the fire water system for make-up water to Isolation Condenser
``B'' since there is no power (``B'' Train) available to the Condensate
Transfer System. The licensee also stated that they have assumed a 10-
minute diagnosis period and that the required time to perform the
action is 13 minutes while the time available is 45 minutes, which
provides a 22-minute margin.
3.1.4.2 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that they conservatively assume that
instrument air is lost for all Appendix R fires based on the fact that
instrument air lines run throughout many areas of the plant. The
licensee's analysis assumes that the air line could potentially fail in
approximately 45 minutes when exposed to the postulated fire.
The licensee also stated that the normal CRD flow control valve is
a single component without a redundant counterpart. Because of this, a
manual bypass is provided to maintain flow around the CRD flow control
valves that fail closed upon loss of instrument air or control cable
damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while monitoring flow at FI-225-2, and close V-15-52
to establish CRD flow to the reactor. Furthermore, OMA 12
would only be necessary if the Isolation Condenser/CRD systems are
utilized for hot shutdown. If OMA 12 becomes necessary, the
licensee stated that they have assumed a 30-minute diagnosis period and
that the required time to perform the action is 15 minutes, while the
time available is 204 minutes, which provides a 159-minute margin.
The licensee stated that OMA 12 essentially duplicates the
Emergency Operating Procedure (EOP) actions for reactor pressure vessel
(RPV) level control. Therefore, if a fire did occur and was not
immediately discovered, any delay in the entry into the appropriate
Fire Support Procedure (FSP) or delay in suppression of the fire would
not significantly affect the performance of this OMA, since the EOPs
would direct the same action to be performed if required.
3.1.5 Conclusion
Given the combustion resistant properties of the most probable
combustible materials, limited ignition sources, and open nature of the
area, it is unlikely that a fire would occur, go undetected or
unsuppressed by station personnel, and damage the safe shutdown
equipment. The low likelihood of damage to safe shutdown equipment due
to a fire in this area, combined with the ability of OMAs 7
and 12 to manipulate the plant in the event of a fire that
damages safe shutdown equipment, provides adequate assurance that safe
shutdown capability is maintained.

3.2 Fire Area OB-FA-9--Office Bldg. Elev. 23[foot]-6,
35[foot]-0, 46[foot]-6

3.2.1 Fire Prevention
The licensee has classified the fire loading in this fire area as
low. The licensee also stated that OB-FA-9 has an administrative fire
loading limit of less than 1.5 hours as determined by the time-
temperature curve contained in American Society of Testing and

[[Page 19800]]

Materials standard E119, ``Standard Test Methods for Fire Tests of
Building Construction and Materials'' (ASTM E119), and that the major
combustibles in the multiplexer (MUX) corridor, which is within OC-FA-
9, are cable insulation and a wood ceiling on top of the MUX enclosure,
which is within the MUX corridor.
3.2.2 Detection, Control, and Extinguishment
The licensee stated that OB-FA-9 has a partial area coverage wet
pipe sprinkler system installed. The licensee further stated that the
area is not provided with an area-wide detection system but that there
is an installed detection system in the main hallways and inside of the
MUX corridor and that it is a high traffic area so a fire would likely
be detected by personnel. The wet pipe sprinkler system, when actuated,
will alarm in the control room to notify operators of a potential fire
event. Extinguishment of a fire in the majority of this area will be
accomplished by the plant fire brigade.
3.2.3 Preservation of Safe Shutdown Capability
The licensee stated that the MUX corridor within OB-FA-9 has a
ceiling height of approximately 10'-6'' and an approximate floor area
of 513 square feet in the MUX corridor where the safe shutdown
equipment is located so it is unlikely that smoke and heat would
accumulate at the height of the safe shutdown equipment and cause a
failure due to fire damage.
3.2.4 OMAs Credited for a Fire in This Area
3.2.4.1 OMA 2--Read Condensate Storage Tank (CST) Local Level
Indicator LI-424-993
In order for OMA 2 to be necessary, the primary CST level
indicator (5F-27) would have to fail as a result of the fire. Should
this occur, indication can only be obtained by reading the local
indicator (LI-424-993) located at the CST. The licensee stated that the
safe shutdown success path structure, system, or component (SSC) cable
for the level indicator is routed in a cable tray located approximately
12 feet above the floor in this area (MUX corridor). The cable enters
the room in the northwest corner and is routed in a cable tray for
approximately 15 feet. It then air drops vertically down into the MUX
enclosure. The credited cable is routed in a cable tray with other
cables and is routed through the wooden ceiling, which also has some
rubber piping insulation on top of the ceiling, thus putting the cable
in close proximity to in situ combustibles. However, there are no
ignition sources in this area. Therefore, due to the lack of ignition
sources, it is not expected that a fire would occur in this area and it
is unlikely that the OMA would be required.
In the unlikely event that a fire does occur and causes the loss of
the primary CST level indicator, OMA 2 is available to locally
read CST level at the local level indicator, LI-424-993. The licensee
also 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 73 minutes, which provides a 36-minute margin.
3.2.4.2 OMA 12--Establish Control Rod Drive (CRD) Flow to
Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that the normal CRD flow control valve is a
single component without a redundant counterpart. Because of this, a
manual bypass is provided to maintain flow around the CRD flow control
valves that fail closed upon loss of instrument air or control cable
damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while monitoring flow at FI-225-2, and close V-15-52
to establish CRD flow to the reactor. Furthermore, OMA 12
would only be necessary if the Isolation Condenser/CRD systems are
utilized for hot shutdown. If OMA 12 becomes necessary, the
licensee stated that they have assumed a 30-minute diagnosis period and
that the required time to perform the action is 15 minutes, while the
time available is 204 minutes, which provides a 159-minute margin.
3.2.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and sufficient volume of the space, it is unlikely that a fire
would occur and go undetected or unsuppressed by the sprinkler system
noted above, or personnel, and damage the safe shutdown equipment. The
low likelihood of damage to safe shutdown equipment due to a fire in
this area, combined with the ability of OMAs 2 and 12
to manipulate the plant in the event of a fire that damages safe
shutdown equipment, provides adequate assurance that safe shutdown
capability is maintained.

3.3 OB-FZ-6A Office Bldg. ``A'' 480V Switchgear (SWGR) Room Elev. 23'-
6''

3.3.1 Fire Prevention
The licensee has classified the fire loading in this fire zone as
moderate. The licensee also stated that this area has an administrative
fire loading limit of less than 3 hours as determined by the ASTM E119
time-temperature curve. The main combustibles in this area are cable
insulation (approximately 81% of loading) and Dow Corning 561 Silicon
transformer liquid (approximately 15% of loading). Additionally, the
transformer liquid has characteristics that minimize the likelihood of
a fire involving the insulating liquid itself.
3.3.2 Detection, Control, and Extinguishment
The licensee stated that OB-FZ-6A has an automatic smoke detection
system, a total flooding automatic Halon 1301 System, and manual fire
fighting capabilities (portable extinguishers and hose stations).
3.3.3 Preservation of Safe Shutdown Capability
The licensee stated that OB-FA-6A has a ceiling height of
approximately 10'-8'' and an approximate floor area of 1157 square feet
so it is unlikely that smoke and heat would accumulate at the height of
the safe shutdown equipment and cause a failure due to fire damage.
3.3.4 OMAs Credited for a Fire in This Zone
3.3.4.1 OMA 2--Read Condensate Storage Tank Local Level
Indicator LI-424-993
In order for OMA 2 to be necessary, the primary CST level
indicator (5F-27) would have to fail as a result of the fire. Should
this occur, indication can only be obtained by reading the local
indicator (LI-424-993) located at the CST. The licensee stated that the
safe shutdown success path cable for the level indicator is routed in a
conduit that leaves a 120 VAC distribution panel and travels
approximately 5 feet vertically to a cable tray that is approximately 9
feet above the floor. The cable is routed with other cables in the
cable tray for approximately 15 feet at which point the cable tray
travels up through the ceiling. The liquid filled transformer is
located approximately 10 feet north of the cable. However, there is a
partial non-rated concrete block wall between the transformer and cable
tray that would provide some protection of direct flame impingement or
radiant heat transfer on the cable tray. The ignition sources in this
fire zone consist

[[Page 19801]]

of enclosed metal electrical cabinets (120 VAC and 125 VDC circuits)
and the liquid filled transformer (4160 VAC to 480 VAC).
In the unlikely event that a fire does occur and damages the
primary CST level indicator, OMA 2 is available to locally
read CST level at local indicator LI-424-993. The licensee also 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 73 minutes, which provides a 36-minute margin.
3.3.4.2 OMA 9--Manually Control 480V Breakers From Remote
Shutdown Panel
In order for OMA 9 to be necessary, damage to the credited
and redundant cables would have to occur due to a fire. The licensee
stated that the credited and redundant cables are located in the same
cable tray with additional cables and that the tray is located
approximately 7 feet above the floor. Other than the cables themselves,
the primary combustible in this area is a liquid filled transformer,
which is located approximately 7 feet from the cable tray. The licensee
also stated that the ignition sources in this fire zone consist of
electrical cabinets (120 VAC and 125 VDC circuits) and the liquid
filled transformer (4160 VAC to 480 VAC). The electrical cabinets are
enclosed metal cabinets, which are located approximately 2 feet from
the credited and redundant cables in some locations.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 9 is available to manually
control the 480V USS 1B2 breakers for CRD Pump NC08B and 1B2M from the
Remote Shutdown Panel. The licensee also stated that they have assumed
a 30-minute diagnosis period and that the required time to perform the
action is 13 minutes while the time available is 180 minutes, which
provides a 137-minute margin.
3.3.4.3 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that the normal CRD flow control valve is a
single component without a redundant counterpart. Because of this, a
manual bypass is provided to maintain flow around the CRD flow control
valves that fail closed upon loss of instrument air or control cable
damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while monitoring flow at FI-225-2, and close V-15-52
to establish CRD flow to the reactor. Furthermore, OMA 12
would only be necessary if the Isolation Condenser/CRD systems are
utilized for hot shutdown. If OMA 12 becomes necessary, the
licensee stated that they have assumed a 30-minute diagnosis period and
that the required time to perform the action is 15 minutes, while the
time available is 204 minutes, which provides a 159-minute margin.
3.3.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and the volume of the space, it is unlikely that a fire would
occur and go undetected or unsuppressed by the smoke detection or Halon
system noted above, or personnel, and damage the safe shutdown
equipment. The low likelihood of damage to safe shutdown equipment due
to a fire in this zone, combined with the ability of OMAs 2,
9, and 12 to manipulate the plant in the event of a
fire that damages safe shutdown equipment, provide adequate assurance
that safe shutdown capability is maintained.

3.4 OB-FZ-6B Office Building ``B'' 480V SWGR Room Elev. 23'-6''

3.4.1 Fire Prevention
The licensee has classified the fire loading in this fire zone as
moderate. The licensee also stated that this area has an administrative
fire loading limit of less than 2 hours as determined by the ASTM E119
time-temperature curve. The main combustibles in this area are cable
insulation (approximately 28% of loading), Thermo-Lag (approximately
29% of loading) and Dow Corning 561 Silicon transformer liquid
(approximately 31% of loading). Also, the transformer liquid has
characteristics that minimize the likelihood of a fire involving the
insulating liquid itself.
3.4.2 Detection, Control, and Extinguishment
The licensee stated that OB-FZ-6B has an automatic smoke detection
system, a total flooding Halon 1301 System, and manual fire fighting
capabilities (portable extinguishers and hose stations).
3.4.3 Preservation of Safe Shutdown Capability
The licensee stated that OB-FA-6B has a ceiling height of
approximately 10'-8'' and an approximate floor area of 679 square feet
so it is unlikely that smoke and heat would accumulate at the height of
the safe shutdown equipment and cause a failure due to fire damage.
3.4.4 OMAs Credited for a Fire in This Zone
3.4.4.1 OMA 7--Align the Fire Water System to the Isolation
Condenser
In order for OMA 7 to be necessary, the loss of the ``B''
Train of power would have to occur due to fire damage. Motor control
center (MCC) 1B21 is located approximately 5 feet from USS 1B2. The
licensee indicated that a credited power cable for the static charger
enters the fire zone through the ceiling of the corridor and then
enters the main portion of the room through the north wall
approximately 9 feet above the floor. It then runs east and down into
MCC 1B21. The cable is located approximately 2 feet above the potential
ignition source, USS 1B2, and runs directly into ignition source MCC
1B21. The credited power cable for MCC 1B21 is routed from USS 1B2 to
MCC 1B21 in a cable tray. This cable tray runs approximately 10 feet
above the floor and approximately 2 feet above the potential ignition
sources, USS 1B2 and MCC 1B21, but it also enters into both as
indicated above. However, both of these ignition sources are contained
in enclosed metal cabinets and are not high voltage. The cable tray is
also located approximately 10 feet from the ignition source of the USS
1B2 transformer, which is located near the west end of the room.
The licensee also indicated that the ``A'' train of power is
credited and available for this fire zone and that the redundant cable
is associated with the ``C'' battery charger, which is fire wrapped
with a 1-hour barrier in this fire zone. It is unlikely that a fire
would develop and cause damage to multiple redundant pieces of
equipment given the spatial relationship between the credited equipment
and ignition sources, the presence of the automatic Halon system, and
the protected ``C'' battery charger cable.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 7 is available to manually
open V-9-2099 and V-11-49 and close V-11-63 and V-11-41 to align the
fire water system for make-up water to Isolation Condenser ``B'' since
there is no power (``B'' Train) available to the Condensate Transfer
System. The licensee also stated that they have assumed a 10-minute
diagnosis period and that the required time to perform the action is 13
minutes while the time

[[Page 19802]]

available is 45 minutes, which provides a 22-minute margin.
3.4.4.2 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that the normal CRD flow control valve is a
single component without a redundant counterpart. Because of this, a
manual bypass is provided to maintain flow around the CRD flow control
valves that fail closed upon loss of instrument air or control cable
damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while monitoring flow at FI-225-2, and close V-15-52
to establish CRD flow to the reactor. Furthermore, OMA 12
would only be necessary if the Isolation Condenser/CRD systems are
utilized for hot shutdown. If OMA 12 becomes necessary, the
licensee stated that they have assumed a 30-minute diagnosis period and
that the required time to perform the action is 15 minutes, while the
time available is 204 minutes, which provides a 159-minute margin.
In the unlikely event that a fire does occur and damages multiple
redundant trains, OMAs 7 and 12 are available to
align the fire water system to the isolation condenser and establish
CRD flow. The locations of these OMAs are in separate fire areas from
Fire Area OB-FZ-6B so a fire in Fire Area OB-FZ-6B would not impact the
locations of the actions.
3.4.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and the volume of the space, it is unlikely that a fire would
occur and go undetected or unsuppressed by the smoke detection or Halon
system noted above, or personnel, and damage the safe shutdown
equipment. The low likelihood of damage to safe shutdown equipment due
to a fire in this zone, combined with the ability of OMAs 7
and 12 to manipulate the plant in the event of a fire that
damages safe shutdown equipment, provides adequate assurance that safe
shutdown capability is maintained.

3.5 OB-FZ-8A Office Bldg. Reactor Recirculation MG Set Room & OB-FZ-8B
Mechanical Equipment Room Elev. 23'-6'' & 35'-0''

3.5.1 Fire Prevention
Fire Zones OB-FZ-8A and 8B are evaluated together for the
combustible loading and fire safe shutdown (FSSD) analysis due to the
lack of rated fire barriers between the zones. The licensee has
classified the fire loading in these fire zones as low. The licensee
also stated that these fire zones have an administrative fire loading
limit of less than 45 minutes as determined by the ASTM E119 time-
temperature curve. There are minimal combustibles in Fire Zone OB-FZ-
8B. The major combustibles in Fire Zone OB-FZ-8A are lubricating oil
(approximately 83% of loading) and cable insulation (approximately 13%
of loading).
3.5.2 Detection, Control, and Extinguishment
The licensee stated that OB-FZ-8A has a partial wet-pipe sprinkler
system with a flow alarm that notifies the control room and that the
area does not have a smoke detection system, however, a duct smoke
detector is located in the exhaust duct of fan EF-1-20. Since operation
of the sprinkler system will alarm in the control room, prompt
notification of and response by, the fire brigade for any required
manual fire fighting activities is expected.
3.5.3 Preservation of Safe Shutdown Capability
The licensee stated that OB-FZ-8A has a ceiling height of
approximately 10'-10'' and an approximate floor area of 2128 square
feet and OB-FZ-8B has a ceiling height of approximately 11'-0'' and an
approximate floor area of 479 square feet so it is unlikely that smoke
and heat would accumulate at the height of the safe shutdown equipment
and cause a failure due to fire damage.
3.5.4 OMAs Credited for a Fire in these Zones
3.5.4.1 OMA 7--Align the Fire Water System to the Isolation
Condenser
In order for OMA 7 to be necessary, the loss of the ``B''
Train of power would have to occur due to fire damage. The licensee
indicated that the cable for the 125 VDC control power is in conduit
that enters this zone through the ceiling in the northwest corner and
then travels south along the ceiling near the west wall approximately 9
feet above the floor and approximately 7 feet from the primary ignition
sources in the area, the motor-generator (MG) Sets, and then leaves
through the floor, where it runs within 2 feet of the ``E'' MG-Set. The
licensee also indicated that the ``A'' train of power is credited and
available for this fire zone and that the redundant cable is associated
with the ``C'' battery and this cable is not located in this fire zone.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 7 is available to manually
open V-9-2099 and V-11-49 and close V-11-63 and V-11-41 to align the
fire water system for make-up water to Isolation Condenser ``B'' since
there is no power (``B'' Train) available to the Condensate Transfer
System. The licensee also stated that they have assumed a 10-minute
diagnosis period and that the required time to perform the action is 13
minutes while the time available is 45 minutes, which provides a 22-
minute margin.
3.5.4.2 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that the normal CRD flow control valve is a
single component without a redundant counterpart. Because of this, a
manual bypass is provided to maintain flow around the CRD flow control
valves that fail closed upon loss of instrument air or control cable
damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while monitoring flow at FI-225-2, and close V-15-52
to establish CRD flow to the reactor. Furthermore, OMA 12
would only be necessary if the Isolation Condenser/CRD systems are
utilized for hot shutdown. If OMA 12 becomes necessary, the
licensee stated that they have assumed a 30-minute diagnosis period and
that the required time to perform the action is 15 minutes, while the
time available is 204 minutes, which provides a 159-minute margin.
3.5.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and the large volume of the space, it is unlikely that a fire
would occur and go undetected or unsuppressed by the smoke detection or
sprinkler systems noted above, or personnel, and damage the safe
shutdown equipment. The low likelihood of damage to safe shutdown
equipment due to a fire in this zone, combined with the ability of OMAs
7 and 12 to manipulate the plant in the event of a
fire that damages safe

[[Page 19803]]

shutdown equipment, provides adequate assurance that safe shutdown
capability is maintained.

3.6 OB-FZ-8C Office Bldg. A/B Battery Room, Tunnel and Electrical Tray
Room Elev. 35'-0''

3.6.1 Fire Prevention
The licensee has classified the fire loading in this fire zone as
low. The licensee also stated that this fire zone has an administrative
fire loading limit of less than 1.5 hours as determined by the ASTM
E119 time-temperature curve. The major combustibles in Fire Zone OB-FZ-
8C are electrolyte-filled plastic battery cases and racks
(approximately 56% of loading) and cable insulation (approximately 39%
of loading).
3.6.2 Detection, Control, and Extinguishment
The licensee stated that OB-FZ-8C has a fixed, total-flooding,
Halon 1301 extinguishing system, area-wide smoke detection that is
installed at the ceiling level and cross-zoned to sound a local alarm,
and an alarm in the control room upon actuation of one detector.
Actuation of a second detector will sound a local alarm, discharge the
Halon system, trip supply and exhaust fans, and close dampers.
3.6.3 Preservation of Safe Shutdown Capability
The licensee stated that OB-FZ-8C has a ceiling height of
approximately 11'-0'' and an approximate floor area of 1292 square feet
so it is unlikely that smoke and heat would accumulate at the height of
the safe shutdown equipment and cause a failure due to fire damage.
3.6.4 OMAs Credited for a Fire in This Zone
3.6.4.1 OMA 2--Read Condensate Storage Tank Local Level
Indicator LI-424-993
In order for OMA 2 to be necessary, damage to the primary
CST level indicator (5F-27) cable would have to occur due to a fire.
Should this occur, indication can only be obtained by reading the local
indicator (LI-424-993) located at the CST. Although there is no
redundant train of equipment for the credited source of obtaining CST
level Indication, the licensee stated that the tray containing the
credited train is located in the Electric Tray Room portion of the
zone, which is separated from the main battery room by a cable tunnel
that is approximately 25 feet long. The licensee also stated that the
credited cable runs in a cable tray with other cables, thus putting it
in close proximity to in-situ hazards, however, due to the size and use
of the room, there are no other credible hazards including transient
combustibles.
In the unlikely event that a fire does occur and causes the loss of
the primary CST level indicator, OMA 2 is available to locally
read CST level at the local level indicator, LI-424-993. The licensee
also 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 73 minutes, which provides a 36-minute margin.
3.6.4.2 OMA 7--Align Fire Water to Isolation Condenser
In order for OMA 7 to be necessary, the loss of the ``B''
Train of power would have to occur due to fire damage. The licensee
indicated that the credited cable is located in the A/B Battery Room
portion (main portion) of this fire zone and that the credited cable
runs in a conduit that begins at 125V DC Distribution Panel B. The
cable is routed in a conduit that runs approximately 1 foot above a
series of vertical cable trays, approximately 8 feet above the ``B'' MG
Set, and approximately 3 feet over the top of the 125V DC ``B''
Distribution Center. However, the ``B'' MG Set is not normally
energized since the static charger is utilized normally for charging
the ``B'' Battery. The licensee also indicated that the battery banks
are another potential ignition source in the room but that they are
located greater than 15 feet from the particular conduit in question
but that the failure of the battery itself may also require the OMA.
The ``A'' train of power is credited and available for this fire zone.
The redundant cable, ``C'' battery, ``C'' Distribution center, etc. are
not located in this fire zone.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 7 is available to manually
open V-9-2099 and V-11-49 and close V-11-63 and V-11-41 to align the
fire water system for make-up water to Isolation Condenser ``B'' since
there is no power (``B'' Train) available to the Condensate Transfer
System. The licensee also stated that they have assumed a 10-minute
diagnosis period and that the required time to perform the action is 13
minutes while the time available is 45 minutes, which provides a 22-
minute margin.
3.6.4.3 OMA 8--Manually Control USS 1A2 ``A'' CRD Pump & 1A2M
From LSP-1A2
In order for OMA 8 to be necessary, damage to the credited
control cables, 1A2M & A CRD Pump, and the redundant control cables,
1B2M and B CRD Pump, would have to occur due to a fire. The licensee
stated that the credited and redundant cables are run in the same cable
tray with additional cables in the Electric Tray Room portion of this
fire area and are separated from the main battery room by a cable
tunnel that is approximately 25-feet long. With the exception of the
cables themselves, there are no other combustibles or ignition sources
and the storage of transient combustibles in this portion of the fire
zone is remote since it is a small room with only one door for access
or egress.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 8 is available to manually
control the 480V USS 1A2 breakers for ``A'' CRD Pump and 1A2M from LSP-
1A2. The licensee also 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 60 minutes, which provides a 22-
minute margin.
3.6.4.4 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that the normal CRD flow control valve is a
single component without a redundant counterpart. Because of this, a
manual bypass is provided to maintain flow around the CRD flow control
valves that fail closed upon loss of instrument air or control cable
damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while monitoring flow at FI-225-2, and close V-15-52
to establish CRD flow to the reactor. Furthermore, OMA 12
would only be necessary if the Isolation Condenser/CRD systems are
utilized for hot shutdown. If OMA 12 becomes necessary, the
licensee stated that they have assumed a 30-minute diagnosis period and
that the required time to perform the action is 15 minutes, while the
time available is 204 minutes, which provides a 159-minute margin.
3.6.4.5 OMA 16--Manually Trip Rx Recirculation Pumps at 4160V
Switchgear
In order for OMA 16 to be necessary, damage to the
credited cables for tripping the recirculation pumps or the loss of the
125 VDC ``B'' Battery and ``B'' Distribution Center would have to occur
due to a fire. The licensee stated that the

[[Page 19804]]

cable tray configuration in the A/B Battery Room is a series of
vertical trays closely stacked together and that the trays containing
the required equipment are located approximately 4 feet from the ``B''
MG Set. However, the ``B'' MG Set is not normally energized since the
static charger is utilized normally for charging the ``B'' Battery. The
licensee also stated that other than the cables themselves, there are
no other combustibles or ignition sources in the area and that the
placement of transient combustibles is remote since access is limited
and the rooms are small in size.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 16 is available to manually
trip Reactor Recirculation Pumps (``A,'' ``C,'' and ``E'') 4160V
Switchgear 1A and 1B. The licensee also stated that they have assumed a
10-minute diagnosis period and that the required time to perform the
action is 13 minutes while the time available is 30 minutes, which
provides a 7-minute margin.
3.6.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and the large volume of the space, it is unlikely that a fire
would occur and go undetected or unsuppressed by the smoke detection or
Halon systems noted above, or personnel, and damage the safe shutdown
equipment. The low likelihood of damage to safe shutdown equipment due
to a fire in this zone, combined with the ability of OMAs 2,
7, 8, 12, and 16 to manipulate the
plant in the event of a fire that damages safe shutdown equipment,
provides adequate assurance that safe shutdown capability is
maintained.

3.7 OB-FZ-10A Office Bldg. Monitor and Change Room and Operations
Support Area Elev. 35[foot]-0 & 46[foot]-6

3.7.1 Fire Prevention
The licensee has classified the fire loading in this fire zone as
low. The licensee also stated that this area has an administrative fire
loading limit of less than 30 minutes as determined by the ASTM E119
time-temperature curve. The major combustibles in this area are cable
insulation (approximately 27% of loading), rubber flooring
(approximately 31% of loading), miscellaneous plastics (approximately
15% of loading) and protective clothing supplies (approximately 20% of
loading). However, since the protective clothing supplies have been
placed in metal cans with self-closing lids they are no longer
considered a contribution to the combustibles in this area.
3.7.2 Detection, Control, and Extinguishment
The licensee stated that OB-FZ-10A has an area-wide smoke detection
system and a wet-pipe automatic sprinkler system installed throughout
the area. In addition, a hose station located nearby, outside the
control room, provides manual suppression capability.
3.7.3 Preservation of Safe Shutdown Capability
The licensee stated that OB-FZ-10A has a ceiling height of
approximately 13'-0'' and an approximate floor area of 2019 square feet
so it is unlikely that smoke and heat would accumulate at the height of
the safe shutdown equipment and cause a failure due to fire damage.
3.7.4 OMAs Credited for a Fire in This Zone
3.7.4.1 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that the normal CRD flow control valve is a
single component without a redundant counterpart. Because of this, a
manual bypass is provided to maintain flow around the CRD flow control
valves that fail closed upon loss of instrument air or control cable
damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while monitoring flow at FI-225-2, and close V-15-52
to establish CRD flow to the reactor. Furthermore, OMA 12
would only be necessary if the Isolation Condenser/CRD systems are
utilized for hot shutdown. If OMA 12 becomes necessary, the
licensee stated that they have assumed a 30-minute diagnosis period and
that the required time to perform the action is 18 minutes, while the
time available is 204 minutes, which provides a 156-minute margin.
3.7.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and the large volume of the space, it is unlikely that a fire
would occur and go undetected or unsuppressed by the smoke detection or
sprinkler systems noted above, or personnel, and damage the safe
shutdown equipment. The low likelihood of damage to safe shutdown
equipment due to a fire in this zone, combined with the ability of OMA
12 to manipulate the plant in the event of a fire that damages
safe shutdown equipment, provides adequate assurance that safe shutdown
capability is maintained.

3.8 RB-FZ-1D Reactor Bldg. Elev. 51'-3''

3.8.1 Fire Prevention
The licensee has classified the fire loading in this fire zone as
low. The licensee also stated that this area has an administrative fire
loading limit of less than 30 minutes as determined by the ASTM E119
time-temperature curve. The main combustible in this area is attributed
to cable insulation (approximately 84% of loading).
3.8.2 Detection, Control, and Extinguishment
The licensee stated that RB-FZ-1D has an area-wide smoke detection
system and an automatic fixed deluge water spray system installed over
cable trays and open hatches. The deluge suppression system protecting
safety-related cable trays is automatically activated by a cross-zoned
detection system consisting of linear heat detection wire located on
top of the cables in each original safety-related cable trays and smoke
detectors are located in each beam pocket at the ceiling.
3.8.3 Preservation of Safe Shutdown Capability
The licensee stated that RB-FZ-1D has a ceiling height of
approximately 21'-0' and an approximate floor area of 9,100 square feet
so it is unlikely that smoke and heat would accumulate at the height of
the safe shutdown equipment and cause a failure due to fire damage.
3.8.4 OMAs Credited for a Fire in This Zone
3.8.4.1 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that the normal CRD flow control valve is a
single component without a redundant counterpart. Because of this, a
manual bypass is provided to maintain flow around the CRD flow control
valves that fail closed upon loss of instrument air or control cable
damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while

[[Page 19805]]

monitoring flow at FI-225-2, and close V-15-52 to establish CRD flow to
the reactor. Furthermore, OMA 12 would only be necessary if
the Isolation Condenser/CRD systems are utilized for hot shutdown. If
OMA 12 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 15 minutes, while the time available is 204
minutes, which provides a 159-minute margin.
3.8.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and the large volume of the space, it is unlikely that a fire
would occur and go undetected or unsuppressed by the smoke detection or
localized water deluge systems noted above, or personnel, and damage
the safe shutdown equipment. The low likelihood of damage to safe
shutdown equipment due to a fire in this zone, combined with the
ability of OMA 12 to manipulate the plant in the event of a
fire that damages safe shutdown equipment, provides adequate assurance
that safe shutdown capability is maintained.

3.9 RB-FZ-1E Reactor Bldg. Elev. 51'[dash]3''

3.9.1 Fire Prevention
The licensee has classified the fire loading in this fire zone as
low. The licensee also stated that this area has an administrative fire
loading limit of less than 30 minutes as determined by the ASTM E119
time-temperature curve. The main combustible in this area is attributed
to cable insulation (approximately 84% of loading).
3.9.2 Detection, Control, and Extinguishment
The licensee stated that RB-FZ-1E has an area-wide smoke detection
system and an automatic fixed deluge water spray system installed over
cable trays and open hatches. The deluge suppression system protecting
safety-related cable trays is automatically activated by a cross-zoned
detection system consisting of linear heat detection wire located on
top of the cables in each original safety-related cable trays and smoke
detectors are located in each beam pocket at the ceiling.
3.9.3 Preservation of Safe Shutdown Capability
The licensee stated that RB-FZ-1E has a ceiling height of
approximately 26'-9'' and an approximate floor area of 12,140 square
feet so it is unlikely that smoke and heat would accumulate at the
height of the safe shutdown equipment and cause a failure due to fire
damage.
3.9.4 OMAs Credited for a Fire in This Zone
3.9.4.1 OMA 11--Locally Read CRD Flow Gauge FI-225-998
In order for OMA 11 to be necessary, the normal local
gauge for CRD flow, FI-225-2, would have to be damaged by fire. The
licensee stated that there are no in-situ combustibles present in the
immediate area surrounding the gauge and that the placement of
transient combustibles is remote since the gauge is surrounded by
piping and tubing. The licensee also stated that the nearest ignition
source is MCC 1A21B, which is located approximately 8 feet from the
flow gauge. However, the solid steel rear of the MCC faces the flow
gauge making it highly unlikely that this potential ignition source
would adversely impact the flow gauge.
OMA 11 would require re-entry into Fire Zone RB-FZ-1E to
manually control CRD System valves V-15-237, V-15-30, and V-15-52
located in this fire zone while monitoring flow at FI-225-998 to
establish CRD flow to the reactor due to the loss of instrument air to
the CRD flow control valve. Fusing of the unprotected CRD valves by
heat from a fire resulting in the valves becoming inoperable is not
considered credible because of the low fire loading, the provision of
automatic fire detection and suppression capability and the heat sink
capability of the water filled piping connected to the valve. Operation
of one of the valves that is in close proximity to these valves was
previously approved in the exemption discussed above.
In the unlikely event that a fire occurs and this flow gauge
becomes unreadable, OMA 11 is available to locally read flow
gauge FI-225-998, which is the redundant instrument that provides the
same data and is mounted on an instrument rack located in Fire Zone RB-
FZ-1D. The licensee also stated that they have assumed a 30-minute
diagnosis period and that the required time to perform the action is
100 minutes, including a 90-minute allowance before re-entry, while the
time available is 204 minutes, which provides a 74-minute margin.
3.9.4.2 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that the normal CRD flow control valve is a
single component without a redundant counterpart. Because of this, a
manual bypass is provided to maintain flow around the CRD flow control
valves that fail closed upon loss of instrument air or control cable
damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to reenter RB-FZ-1E and
manually open V-15-237, throttle V-15-30 while monitoring flow at FI-
225-2, and close V-15-52 to establish CRD flow to the reactor.
Furthermore, OMA 12 would only be necessary if the Isolation
Condenser/CRD systems are utilized for hot shutdown. If OMA 12
becomes necessary, the licensee stated that they have assumed a 30-
minute diagnosis period and that the required time to perform the
action is 100 minutes, including a 90-minute allowance before re-entry,
while the time available is 204 minutes, which provides a 74-minute
margin.
3.9.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and the large volume of the space, it is unlikely that a fire
would occur and go undetected or unsuppressed by the smoke detection or
localized water deluge systems noted above, or personnel, and damage
the safe shutdown equipment. The low likelihood of damage to safe
shutdown equipment due to a fire in this zone, combined with the
ability of OMAs 11 and 12 to manipulate the plant in
the event of a fire that damages safe shutdown equipment, provides
adequate assurance that safe shutdown capability is maintained.

3.10 RB-FZ-1F3 Reactor Bldg. Northwest Corner Elev. -19[foot]-
6

3.10.1 Fire Prevention
The licensee has classified the fire loading in this fire zone as
low. The licensee also stated that this area has an administrative fire
loading limit of less than 30 minutes as determined by the ASTM E119
time-temperature curve. The major combustibles in this area are cable
insulation (approximately 58% of loading), ladders (approximately 16%
of loading) and lubricating oil in pumps (approximately 16% of
loading).
3.10.2 Detection, Control, and Extinguishment
The licensee stated that RB-FZ-1F3 has smoke detectors which alarm
locally and in the control room installed over hazards rather than
mounted at the ceiling. Fire extinguishers are also

[[Page 19806]]

provided for manual fire fighting backup. Hose lines are available from
outside hydrants and hose houses.
3.10.3 Preservation of Safe Shutdown Capability
The licensee stated that RB-FZ-1F3 has a ceiling height of
approximately 41'-6'' and an approximate floor area of 560 square feet
so it is unlikely that smoke and heat would accumulate at the height of
the safe shutdown equipment and cause a failure due to fire damage.
3.10.4 OMAs Credited for a Fire in This Zone
3.10.4.1 OMA 13--Manually Align Core Spray to CST To Provide
Reactor Coolant Makeup
In order for OMA 13 to be necessary, both CRD pumps
located in this area would have to become damaged due to a fire. The
licensee stated that the pumps are separated by a horizontal distance
of approximately 6 feet and that the associated cables and conduits are
in close proximity to each other. The licensee also stated that the
primary ignition sources in the area, aside from the pumps themselves,
are located approximately 18 feet from the CRD pumps.
In the unlikely event that a fire occurs and causes damage to both
pumps, OMA 13 is available to re-enter this fire zone and
manually open Core Spray valves V-20-1 and V-20-2 and close V-20-4 (V-
20-2 and V-20-4 are located in Fire Zone RB-FZ-1F2) to provide Reactor
Coolant Makeup from the CST for Fire Zone RB-FZ-1F3. The licensee also
stated that they have assumed a 30-minute diagnosis period and that the
required time to perform the action is 35 minutes while the time
available is 204 minutes, which provides a 139-minute margin.
3.10.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and large volume of the space it is unlikely that a fire would
occur and go undetected or unsuppressed by the smoke detection system
or personnel and damage the safe shutdown equipment. The low likelihood
of damage to safe shutdown equipment due to a fire in this zone,
combined with the ability of OMA 13 to manipulate the plant in
the event of a fire that damages safe shutdown equipment, provides
adequate assurance that safe shutdown capability is maintained.

3.11 RB-FZ-1F5 Reactor Bldg. Torus Room Elev. -19'-6''

3.11.1 Fire Prevention
The licensee has classified the fire loading in this fire zone as
low. The licensee also stated that this area has an administrative fire
loading limit of less than 30 minutes as determined by the ASTM E119
time-temperature curve. The major combustibles in this area are cable
insulation (approximately 19% of loading) and gratings (approximately
76% of loading). The grating, which is the largest plastic material in
this area, has a low flame spread rating (less than 25).
3.11.2 Detection, Control, and Extinguishment
The licensee stated that RB-FZ-1F5 does not have a detection or
suppression systems. The NRC staff finds that the, because of the low
amount of combustible material in the area and low flame spread rating
of the majority of this material, a fire in this zone is not expected
to be of significant size or duration.
3.11.3 Preservation of Safe Shutdown Capability
The licensee stated that RB-FZ-1F5 is a voluminous area with an
approximate floor area of 11450 square feet and a ceiling height of
approximately 41[foot]-6, therefore, it is unlikely that
smoke and heat from a fire in the area would accumulate at the location
of the instrument air line and cause a loss of instrument air.
3.11.4 OMAs Credited for a Fire in This Zone
3.11.4.1 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that the normal CRD flow control valve is a
single component without a redundant counterpart. Because of this, a
manual bypass is provided to maintain flow around the CRD flow control
valves that fail closed upon loss of instrument air or control cable
damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while monitoring flow at FI-225-2, and close V-15-52
to establish CRD flow to the reactor. Furthermore, OMA 12
would only be necessary if the Isolation Condenser/CRD systems are
utilized for hot shutdown. If OMA 12 becomes necessary, the
licensee stated that they have assumed a 30-minute diagnosis period and
that the required time to perform the action is 15 minutes, while the
time available is 204 minutes, which provides a 159-minute margin.
3.11.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and the large volume of the area, it is unlikely that a fire
would occur and go undetected or unsuppressed by personnel, and damage
the safe shutdown equipment. The low likelihood of damage to safe
shutdown equipment due to a fire in this zone, combined with the
ability of OMA 12 to manipulate the plant in the event of a
fire that damages safe shutdown equipment, provides adequate assurance
that safe shutdown capability is maintained.

3.12 RB-FZ-1G Reactor Bldg. Shutdown Cooling Room Elev. 38'-0'' & 51'-
3''

3.12.1 Fire Prevention
The licensee has classified the fire loading in this fire zone as
low. The licensee also stated that this area has an administrative fire
loading limit of less than 30 minutes as determined by the ASTM E119
time-temperature curve. The main combustibles in this area are cable
insulation (approximately 12% of loading), plastic (approximately 57%
of loading) and Class A combustibles (approximately 14% of loading).
The grating, which is the majority of the plastic material in this
area, has a low flame spread rating (less than 25).
3.12.2 Detection, Control, and Extinguishment
The licensee stated that RB-FZ-1G is provided with a smoke
detection system that alarms locally and in the control room to provide
prompt notification of a potential fire event.
3.12.3 Preservation of Safe Shutdown Capability
The licensee stated that RB-FZ-1G has a ceiling height of
approximately 21', measured from the 51'-3'' elevation, and an
approximate floor area of 1609 square feet so it is unlikely that smoke
and heat would accumulate at the height of the safe shutdown equipment
and cause a failure due to fire damage.
3.12.4 OMAs Credited for a Fire in This Zone
3.12.4.1 OMA 11--Locally Read CRD Flow Gauge FI-225-998
In order for OMA 11 to be necessary, the normal local
gauge for CRD flow, FI-

[[Page 19807]]

225-2, located in Fire Zone RB-FZ-1E or its associated cables, would
have to be damaged by fire. The licensee stated that there are no in-
situ combustibles present in the immediate area surrounding the gauge
and that the placement or storage of transient combustibles is remote
since the gauge is surrounded by piping and tubing. The licensee also
stated that the nearest ignition source is MCC 1A21B, which is located
approximately 8 feet from the flow gauge. However, the solid steel rear
of the MCC faces the flow gauge making it highly unlikely that this
potential ignition source would adversely impact the flow gauge.
In the unlikely event that a fire occurs and this flow gauge
becomes unreadable, OMA 11 is available to locally read flow
gauge FI-225-998, which is the redundant instrument that provides the
same data and is mounted on an instrument rack located in Fire Zone RB-
FZ-1D. The licensee also stated that they have assumed a 30-minute
diagnosis period and that the required time to perform the action is
100 minutes, including a 90-minute allowance before re-entry, while the
time available is 204 minutes, which provides a 74-minute margin.
3.12.4.2 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that the normal CRD flow control valve is a
single component without a redundant counterpart. Because of this, a
manual bypass is provided to maintain flow around the CRD flow control
valves that fail closed upon loss of instrument air or control cable
damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while monitoring flow at FI-225-2, and close V-15-52
to establish CRD flow to the reactor. Furthermore, OMA 12
would only be necessary if the Isolation Condenser/CRD systems are
utilized for hot shutdown. If OMA 12 becomes necessary, the
licensee stated that they have assumed a 30-minute diagnosis period and
that the required time to perform the action is 100 minutes, including
a 90-minute allowance before re-entry, while the time available is 204
minutes, which provides a 74-minute margin.
3.12.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and large volume of the space, it is unlikely that a fire
would occur and go undetected or unsuppressed by the smoke detection
system or personnel and damage the safe shutdown equipment. The low
likelihood of damage to safe shutdown equipment due to a fire in this
zone, combined with the ability of OMAs 11 and 12 to
manipulate the plant in the event of a fire that damages safe shutdown
equipment, provides adequate assurance that safe shutdown capability is
maintained.

3.13 TB-FA-3A Turbine Bldg. 4160V Emergency Switchgear Vault 1C Elev.
23'-6''

3.13.1 Fire Prevention
The licensee has classified the fire loading in this fire area as
low. The licensee also stated that this area has an administrative fire
loading limit of less than 30 minutes as determined by the ASTM E119
time-temperature curve. There are minimal amounts of cable insulation
(approximately 5% of loading) miscellaneous plastic (approximately 73%
of loading) and class A combustibles such as paper for procedures
(approximately 20% of loading) in this area.
3.13.2 Detection, Control, and Extinguishment
The licensee stated that TB-FA-3A is provided with an area-wide
smoke detection system and a total-flooding, manually actuated
CO2 system.
3.13.3 Preservation of Safe Shutdown Capability
The licensee stated that TB-FA-3A has a ceiling height of
approximately 21' and an approximate floor area of 336 square feet so
it is unlikely that smoke and heat would accumulate at the height of
the safe shutdown equipment and cause a failure due to fire damage.
3.13.4 OMAs Credited for a Fire in This Area
3.13.4.1 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that the normal CRD flow control valve is a
single component without a redundant counterpart. Because of this, a
manual bypass is provided to maintain flow around the CRD flow control
valves that fail closed upon loss of instrument air or control cable
damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while monitoring flow at FI-225-2, and close V-15-52
to establish CRD flow to the reactor. Furthermore, OMA 12
would only be necessary if the Isolation Condenser/CRD systems are
utilized for hot shutdown. If OMA 12 becomes necessary, the
licensee stated that they have assumed a 30-minute diagnosis period and
that the required time to perform the action is 15 minutes, while the
time available is 204 minutes, which provides a 159-minute margin.
3.13.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and large volume of the space, it is unlikely that a fire
would occur and go undetected or unsuppressed by the smoke detection or
CO2 systems, or personnel, and damage the safe shutdown
equipment. The low likelihood of damage to safe shutdown equipment due
to a fire in this area, combined with the ability of OMA 12 to
manipulate the plant in the event of a fire that damages safe shutdown
equipment, provides adequate assurance that safe shutdown capability is
maintained.

3.14 TB-FA-26 Turbine Bldg. 125V DC Battery Room C Elev. 23'-6''

3.14.1 Fire Prevention
The licensee has classified the fire loading in this fire area as
moderate. The licensee also stated that this area has an administrative
fire loading limit of less than 90 minutes as determined by the ASTM
E119 time-temperature curve. The major combustibles in this area are
plastic, which is contributed by the battery cases (approximately 92%
of loading) and cable insulation (approximately 6% of loading).
3.14.2 Detection, Control, and Extinguishment
The licensee stated that TB-FA-26 has an area-wide automatic pre-
action sprinkler system and an area-wide smoke detection system
installed. Additionally, the licensee identified that the battery cases
are filled with water which would provide some resistance to combustion
of the cases.
3.14.3 Preservation of Safe Shutdown Capability
The licensee stated that there are no specific cables in this fire
area associated with the OMAs identified for Fire Area TB-FA-26 and
that the only

[[Page 19808]]

FSSD component and cable located in this fire area is associated with
the ``C'' battery. Additionally, per the Oyster Creek Updated Final
Safety Analysis Report, Section 8.3.2.4, the ``B'' 125V DC distribution
system is redundant to the ``C'' system and the two systems are
physically independent.
3.14.4 OMAs Credited for a Fire in This Area
The licensee stated that this fire area is wholly contained within
Fire Zone TB-FZ-11C (A and B 4160V Room) and that all cables to TB-FA-
26 must traverse TB-FZ-11C. Therefore, TB-FA-26 and TB-FZ-11C were
analyzed together for safe shutdown purposes and the OMAs are
duplicated for these two plant areas. Refer to Section 3.16 below for
NRC staff's evaluation of the feasibility of OMAs 1,
3, 6, and 12, which are common to both
areas.
3.14.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and lack of multiple safe shutdown trains in this area, it is
unlikely that a fire would occur and go undetected or unsuppressed by
the smoke detection or sprinkler systems, or personnel, and damage the
safe shutdown equipment. The low likelihood of damage to safe shutdown
equipment due to a fire in this area, combined with the ability of OMAs
1, 3, 6, and 12 to manipulate the
plant in the event of a fire that damages safe shutdown equipment,
provides adequate assurance that safe shutdown capability is
maintained.

3.15 TB-FZ-11B Turbine Bldg. Lube Oil Storage, Purification and Pumping
Area Elev. 0'-0'', 27'-0'', and 36'-0''

3.15.1 Fire Prevention
The licensee has classified the fire loading in this fire zone as
high. The licensee also stated that this fire zone has administrative
controls such that additional combustible materials are not introduced
into this zone and defense-in-depth features to control a potential oil
fire in this zone. The major combustibles in this area are lubricating
oil (approximately 99% of loading) and cable insulation (approximately
0.3% of loading). The amount of oil contained in the lube oil storage
tanks in this fire zone results in a combustible loading of
approximately 14 hours.
3.15.2 Detection, Control, and Extinguishment
The licensee stated that TB-FZ-11B has automatic suppression
systems installed over principal combustibles and a rate of rise/fixed
temperature fire detection system installed at the lube oil tank. A
closed head automatic sprinkler system protects cable trays and open
head water spray deluge system protects oil handling equipment and the
oil storage tank. Thermal detectors are located in close proximity to
the lube oil tank so that a lube oil fire would be quickly detected,
which in turn would activate the deluge system for extinguishment.
Additionally, the licensee stated that there are fire extinguishers
provided throughout the zone and that aqueous film-forming foam (AFFF)
is staged in the Fire Brigade van for use if necessary.
3.15.3 Preservation of Safe Shutdown Capability
The licensee stated that the ceiling heights in the area are
approximately 9'-0'' in the basement hallway, approximately 19'-0'' in
the basement stairs, approximately 26'-0'' on the first floor of the
area, and approximately 42'-0'' on the second floor of the area.
Additionally, the licensee stated that the floor area, measured at the
0'-0'' elevation is approximately 3,175 square feet.
3.15.4 OMAs Credited for a Fire in This Zone
3.15.4.1 OMA 1--Manually Trip 4160V 1D Breakers and Control
USS 1B2 & 1B3 Breakers Locally at LSP-1D
In order for OMA 1 to be necessary, damage to the credited
and redundant cables would have to occur due to a fire. The licensee
stated that these cables are located in the same tray with additional
cables and are generally located approximately 14 feet above the floor.
The licensee also stated that the cables pass over the top of potential
ignition sources MCC 1A12 and MCC 1B12 and that the cables are located
approximately 6 feet above these ignition sources. Additionally, the
lube oil tanks are located below the cables, although not directly
below, with a distance of approximately 26 feet separating the cables
and the tanks. The cables are also located approximately 20 feet from
ignition sources MCC 1A12A and 1B12A.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 1 is available to manually
trip the 4160V 1D breakers and control USS 1B2 and the 1B3 480V
breakers locally at LSP-1D. The licensee also stated that they have
assumed a 10-minute diagnosis period and that the required time to
perform the action is 19 minutes while the time available is 45
minutes, which provides a 16-minute margin.
3.15.4.2 OMA 2--Read Condensate Storage Tank Local Level
Indicator LI-424-993
In order for OMA 2 to be necessary, damage to the primary
CST level indicator (5F-27) cable would have to occur due to a fire.
The licensee stated that this cable is located approximately 20 feet
above the floor and that the nearest primary ignition source in the
area, the lube oil tank, is located approximately 7 feet below the
cable. With the exception of the cables themselves, there are no other
ignition sources or combustibles located near the cables.
In the unlikely event that a fire does occur and damages the
primary CST level indicator, OMA 2 is available to locally
read CST level at the local indicator, LI-424-993, located at the CST.
The licensee also 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 73 minutes, which provides a 36-minute
margin.
3.15.4.3 OMA 3--Manually Control 1B3M Breaker at LSP-1B3
In order for OMA 3 to be necessary, the credited and
redundant cables would have to be damaged due to a fire. The licensee
stated that these cables are located in the same tray with additional
cables and are generally located approximately 14 feet above the floor.
The licensee also stated that the cables pass over the top of potential
ignition sources MCC 1A12 and MCC 1B12 and that the cables are located
approximately 6 feet above these ignition sources. Additionally, the
lube oil tanks are located below the cables, although not directly
below, with a distance of approximately 26 feet separating the cables
and the tanks. The cables are also located approximately 20 feet from
ignition sources MCC 1A12A and 1B12A.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 3 is available to manually
control the 1B3M breaker locally from LSP-1B3. The licensee also stated
that they have assumed a 10-minute diagnosis period and that the
required time to perform the action is 10 minutes while the time
available is 45 minutes, which provides a 25-minute margin.
3.15.4.4 OMA 4--Manually Control Condensate Transfer Pump 1-2
from LSP-1B32
In order for OMA 4 to be necessary, damage to the credited
and redundant cables for the Condensate Transfer

[[Page 19809]]

Pump 1-2 would have to be damaged due to a fire. The licensee stated
that these cables are located in the same tray with additional cables
and are generally located approximately 20 feet above the floor and
approximately 7 feet above the lube oil tank.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 4 is available to manually
control Condensate Transfer Pump 1-2 locally from LSP-1B32. The
licensee also stated that they have assumed a 10-minute diagnosis
period and that the required time to perform the action is 10 minutes
while the time available is 45 minutes, which provides a 25-minute
margin.
3.15.4.5 OMA 6--Manually Reclose Feeder Breaker MCC 1B32 at
USS 1B3
In order for OMA 6 to be necessary, power to USS 1B3 or
the 1B 4160V switchgear would have to be lost due to a fire. The
licensee stated that these cables are located in the same tray with
additional cables and are generally located approximately 14 feet above
the floor. The licensee also stated that the cables pass over the top
of potential ignition sources MCC 1A12 and MCC 1B12 and that the cables
are located approximately 6 feet above these ignition sources.
Additionally, the lube oil tanks are located below the cables, although
not directly below, with a distance of approximately 26 feet separating
the cables and the tanks. The cables are also located approximately 20
feet from ignition sources MCC 1A12A and 1B12A.
In the unlikely event that a fire does occur and causes a loss of
power to USS 1B3 or a loss of the 1B 4160V switchgear, OMA 6
is available to manually re-close Feeder Breaker MCC 1B32 at USS 1B3
due to an under voltage trip. The licensee also stated that they have
assumed a 10-minute diagnosis period and that the required time to
perform the action is 6 minutes while the time available is 45 minutes,
which provides a 29-minute margin.
3.15.4.6 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that the normal CRD flow control valve is a
single component without a redundant counterpart. Because of this, a
manual bypass is provided to maintain flow around the CRD flow control
valves that fail closed upon loss of instrument air or control cable
damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while monitoring flow at FI-225-2, and close V-15-52
to establish CRD flow to the reactor. Furthermore, OMA 12
would only be necessary if the Isolation Condenser/CRD systems are
utilized for hot shutdown. If OMA 12 becomes necessary, the
licensee stated that they have assumed a 30-minute diagnosis period and
that the required time to perform the action is 15 minutes, while the
time available is 204 minutes, which provides a 159-minute margin.
3.15.4.7 OMA 16--Manually Trip Rx Recirculation Pumps at 4160V
Switchgear
In order for OMA 16 to be necessary, the credited and
redundant cables would have to be damaged due to a fire. The licensee
stated that these cables are located in the same tray with additional
cables and are generally located approximately 14 feet above the floor.
The licensee also stated that the cables pass over the top of potential
ignition sources MCC 1A12 and MCC 1B12 and that the cables are located
approximately 6 feet above these ignition sources. Additionally, the
lube oil tanks are located below the cables, although not directly
below, with a distance of approximately 26 feet separating the cables
and the tanks. The cables are also located approximately 20 feet from
ignition sources MCC 1A12A and 1B12A.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 16 is available to manually
trip Reactor Recirculation Pumps (``A,'' ``B,'' ``C,'' ``D'' and ``E'')
4160V Switchgear 1A and 1B. The licensee also stated that they have
assumed a 10-minute diagnosis period and that the required time to
perform the action is 13 minutes while the time available is 30
minutes, which provides a 7-minute margin.
3.15.5 Conclusion
Although the fire loading for this zone is high, the limited
ignition sources, large volume of the space, and the detection and
suppression system make it unlikely that a fire would occur and go
undetected or unsuppressed and damage the safe shutdown equipment.
Additionally, the availability of fire extinguishers and AFFF, which is
effective against oil based fires, provides an augmented ability to
suppress a fire prior to damaging safe shutdown equipment. The low
likelihood of damage to safe shutdown equipment due to a fire in this
zone, combined with the ability of OMAs 1, 2,
3, 4, 6, 12, and 16 to
manipulate the plant in the event of a fire that damages safe shutdown
equipment, provides adequate assurance that safe shutdown capability is
maintained.

3.16 TB-FZ-11C Turbine Bldg. 4160V SWGR Room 1A and 1B Elev. 23'-6''

3.16.1 Fire Prevention
The licensee has classified the fire loading in this fire zone as
low. The licensee also stated that this area has an administrative fire
loading limit of less than 30 minutes as determined by the ASTM E119
time-temperature curve. The main combustible loading is attributed to
cable insulation (approximately 73% of loading) and plastic
(approximately 17% of loading).
3.16.2 Detection, Control, and Extinguishment
The licensee stated that TB-FZ-11C has an area-wide smoke detection
system and an area-wide automatic fixed pre-action sprinkler system
installed (except in the small caged area located to the east of Fire
Area TB-FA-3A).
3.16.3 Preservation of Safe Shutdown Capability
The licensee stated that TB-FZ-11C has a ceiling height of
approximately 21'-8'' and an approximate floor area of 2666 square feet
so it is unlikely that smoke and heat would accumulate at the height of
the safe shutdown equipment and cause a failure due to fire damage.
3.16.4 OMAs Credited for a Fire in This Zone
3.16.4.1 OMA 1--Manually Trip 4160V 1D Breakers and Control
USS 1B2 & 1B3 Breakers Locally at LSP-1D
In order for OMA 1 to be necessary, the credited cables
for USS 1B2 and 1B3 4160V breakers and the redundant cables for USS 1A2
and 1A3 breakers would have to be damaged due to a fire. The licensee
stated that these cables are located in the same tray with additional
cables and are generally located at least 17 feet above the floor. The
licensee also stated that the tray passes over the top of potential
ignition source ``B'' 4160V switchgear and that the cables are located
approximately 9 feet above this ignition source and 3 feet above the
iso-phase bus duct at their closest point.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 1 is available to manually
trip the 4160V 1D breakers and control USS 1B2 and the 1B3 480V
breakers locally at LSP-1D. The licensee

[[Page 19810]]

also stated that they have assumed a 10-minute diagnosis period and
that the required time to perform the action is 24 minutes while the
time available is 45 minutes, which provides an 11-minute margin.
3.16.4.3 OMA 3--Manually Control 1B3M Breaker at LSP-1B3
In order for OMA 3 to be necessary, the credited and
redundant cables would have to be damaged due to a fire. The licensee
stated that these cables are located in the same tray with additional
cables and are generally located at least 17 feet above the floor. The
licensee also stated that the tray passes over the top of potential
ignition source ``B'' 4160V switchgear and that the cables are located
approximately 9 feet above this ignition source and 3 feet above the
iso-phase bus duct at their closest point.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 3 is available to manually
control the 1B3M breaker locally from LSP-1B3. The licensee also stated
that they have assumed a 10-minute diagnosis period and that the
required time to perform the action is 10 minutes while the time
available is 45 minutes, which provides a 25-minute margin.
3.16.4.5 OMA 6--Manually Reclose Feeder Breaker MCC 1B32 at
USS 1B3
In order for OMA 6 to be necessary, power to USS 1B3 or
the 1B 4160V switchgear would have to be lost due to a fire. The
licensee stated that these cables are located in the same tray with
additional cables and are generally located at least 17 feet above the
floor. The licensee also stated that the tray passes over the top of
potential ignition source ``B'' 4160V switchgear and that the cables
are located approximately 9 feet above this ignition source and 3 feet
above the iso-phase bus duct at their closest point.
In the unlikely event that a fire does occur and causes a loss of
power to USS 1B3 or a loss of the 1B 4160V switchgear, OMA 6
is available to manually re-close Feeder Breaker MCC 1B32 at USS 1B3
due to an under voltage trip. The licensee also stated that they have
assumed a 10-minute diagnosis period and that the required time to
perform the action is 6 minutes while the time available is 45 minutes,
which provides a 29-minute margin.
3.16.4.6 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that the normal CRD flow control valve is a
single component without a redundant counterpart. Because of this, a
manual bypass is provided to maintain flow around the CRD flow control
valves that fail closed upon loss of instrument air or control cable
damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while monitoring flow at FI-225-2, and close V-15-52
to establish CRD flow to the reactor. Furthermore, OMA 12
would only be necessary if the Isolation Condenser/CRD systems are
utilized for hot shutdown. If OMA 12 becomes necessary, the
licensee stated that they have assumed a 30-minute diagnosis period and
that the required time to perform the action is 15 minutes, while the
time available is 204 minutes, which provides a 159-minute margin.
3.16.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and large volume of the space, it is unlikely that a fire
would occur and go undetected or unsuppressed by the smoke detection or
sprinkler systems noted above, or personnel, and damage the safe
shutdown equipment. The low likelihood of damage to safe shutdown
equipment due to a fire in this zone, combined with the ability of OMAs
1, 3, 6, and 12 to manipulate the
plant in the event of a fire that damages safe shutdown equipment,
provides adequate assurance that safe shutdown capability is
maintained.

3.17 TB-FZ-11D Turbine Bldg. Basement Floor South End Elev. 3'-6''

3.17.1 Fire Prevention
The licensee has classified the fire loading in this fire zone as
low. The licensee also stated that this area has an administrative fire
loading limit of less than 30 minutes as determined by the ASTM E119
time-temperature curve. The major combustibles in this area are cable
insulation (approximately 29% of loading), Dow Corning 561 Silicon
transformer liquid (approximately 15% of loading) and lubricating oil
(approximately 40% of loading).
3.17.2 Detection, Control, and Extinguishment
The licensee stated that an automatic wet-pipe sprinkler system and
an automatic water spray system located at the hydrogen seal oil unit
are installed in the area.
3.17.3 Preservation of Safe Shutdown Capability
The licensee stated that TB-FZ-11D has a ceiling height of
approximately 19' and an approximate floor area of 9668 square feet so
it is unlikely that smoke and heat would accumulate at the height of
the safe shutdown equipment and cause a failure due to fire damage.
3.17.4 OMAs Credited for a Fire in This Zone
3.17.4.1 OMA 1--Manually Trip 4160V 1D Breakers and Control
USS 1B2 & 1B3 Breakers Locally at LSP-1D
In order for OMA 1 to be necessary, the credited cables
for USS 1B2 and 1B3 4160V breakers and the redundant cables for USS 1A2
and 1A3 breakers would have to be damaged due to a fire. The licensee
stated that these cables are located in the same tray with additional
cables and are generally located at least 15 feet above the floor. The
primary combustible fuel load in the area is the cables themselves and
storage of transient combustibles is limited due to a sump and
abandoned acid/caustic tanks located in the area.
The licensee also stated that the primary ignition sources in the
area near the cable trays are the Turbine Building Closed Cooling Water
Pumps and USS 1A1 and its associated transformer (4160V to 480V
transformer). However, the Turbine Building Closed Cooling Water Pumps
contain less than 5 gallons of oil and are enclosed in metal casings
and the cable tray containing the cables is approximately 13 feet from
the top of the pumps/motors. The top of USS 1A1 and its associated
transformer are located approximately 30 feet diagonally from the
credited cables and approximately 15 feet diagonally from the redundant
cables. Additionally, there is a concrete ceiling beam, with a water
curtain sprinkler system attached, which would provide some shielding
for the cables from potential products of combustion generated by this
ignition source. Sprinkler heads are also located in a ceiling pocket
between the concrete ceiling beam and the USS 1A1 and transformer.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 1 is available to manually
trip the 4160V 1D breakers and control USS 1B2 and the 1B3 480V
breakers locally at LSP-1D. The licensee also stated that they have
assumed a 10-minute diagnosis period and that the required time to
perform the action is 24 minutes while the time available is 45
minutes, which provides an 11-minute margin.

[[Page 19811]]

3.17.4.2 OMA 3--Manually Control 1B3M Breaker at LSP-1B3
In order for OMA 3 to be necessary, the credited and
redundant cables would have to be damaged due to a fire. The licensee
stated that these cables are located in the same tray with additional
cables and are generally located at least 15 feet above the floor. The
primary combustible fuel load in the area is the cables themselves and
storage of transient combustibles is limited due to a sump and
abandoned acid/caustic tanks located in the area.
The licensee also stated that the primary ignition sources in the
area near the cable trays are the Turbine Building Closed Cooling Water
Pumps and USS 1A1 and its associated transformer (4160V to 480V
transformer). However, the Turbine Building Closed Cooling Water Pumps
contain less than 5 gallons of oil and are enclosed in metal casings
and the cable tray containing the cables is approximately 13 feet from
the top of the pumps/motors. The top of USS 1A1 and its associated
transformer are located approximately 30 feet diagonally from the
credited cables and approximately 15 feet diagonally from the redundant
cables. Additionally, there is a concrete ceiling beam, with a water
curtain sprinkler system attached, which would provide some shielding
for the cables from potential products of combustion generated by this
ignition source. Sprinkler heads are also located in a ceiling pocket
between the concrete ceiling beam and the USS 1A1 and transformer.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 3 is available to manually
control the 1B3M breaker locally from LSP-1B3. The licensee also stated
that they have assumed a 10-minute diagnosis period and that the
required time to perform the action is 10 minutes while the time
available is 45 minutes, which provides a 25-minute margin.
3.17.4.3 OMA 5--Manually Control Diesel Generator 2
from LSP-DG2
In order for OMA 5 to be necessary, damage to the credited
and redundant cables for Diesel Generator 1 and 2
would have to occur due to a fire. The licensee stated that the
credited and redundant cables are located in the same cable trays, in
some areas, with additional cables and that the cable trays are
approximately 17 feet above the floor. The primary combustible fuel
load in the area is the cables themselves and storage of transient
combustibles is limited due to a sump and abandoned acid/caustic tanks
located in the area.
The licensee also stated that the primary ignition sources in the
area are the Turbine Building Closed Cooling Water Pumps and USS 1A1
and its associated transformer. The licensee stated that the Turbine
Building Closed Cooling Water Pumps contain less than 5 gallons of oil,
are enclosed in metal casings, and are located approximately 13 feet
from the cable tray containing the credited and redundant cables.
Additionally, USS 1A1 and its associated transformer are located
approximately 8 feet directly below some of the credited cables for
Diesel Generator 2, however, the redundant cables are
approximately 25 feet from this portion of the credited cables.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 5 is available to manually
control Emergency Diesel Generator 2 from LSP-DG2. The
licensee also stated that they have assumed a 10-minute diagnosis
period and that the required time to perform the action is 14 minutes
while the time available is 45 minutes, which provides a 21-minute
margin.
3.17.4.4 OMA 6--Manually Reclose Feeder Breaker MCC 1B32 at
USS 1B3
In order for OMA 6 to be necessary, power to USS 1B3 or
the 1B 4160V switchgear would have to be lost due to a fire. The
licensee stated that these cables are located in the same tray with
additional cables and are generally located at least 15 feet above the
floor. The primary combustible fuel load in the area is the cables
themselves and storage of transient combustibles is limited due to a
sump and abandoned acid/caustic tanks located in the area.
The licensee also stated that the primary ignition sources in the
area near the cable trays are the Turbine Building Closed Cooling Water
Pumps and USS 1A1 and its associated transformer (4160V to 480V
transformer). However, the Turbine Building Closed Cooling Water Pumps
contain less than 5 gallons of oil and are enclosed in metal casings
and the cable tray containing the cables is approximately 13 feet from
the top of the pumps/motors. The top of USS 1A1 and its associated
transformer are located approximately 30 feet diagonally from the
credited cables and approximately 15 feet diagonally from the redundant
cables. Additionally, there is a concrete ceiling beam, with a water
curtain sprinkler system attached, which would provide some shielding
for the cables from potential products of combustion generated by this
ignition source. Sprinkler heads are also located in a ceiling pocket
between the concrete ceiling beam and the USS 1A1 and transformer.
In the unlikely event that a fire does occur and causes a loss of
power to USS 1B3 or loss of the 1B 4160V switchgear, OMA 6 is
available to manually re-close Feeder Breaker MCC1B32 at USS 1B3 due to
an under voltage trip. The licensee also stated that they have assumed
a 10-minute diagnosis period and that the required time to perform the
action is 6 minutes while the time available is 45 minutes, which
provides a 29-minute margin.
3.17.4.5 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that although the USSs powering the air
compressors are located 35 feet apart from each other, the power cables
are located in the same cable trays for at least 45 feet and that the
normal CRD flow control valve is a single component without a redundant
counterpart. Because of this, a manual bypass is provided to maintain
flow around the CRD flow control valves that fail closed upon loss of
instrument air or control cable damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while monitoring flow at FI-225-2, and close V-15-52
to establish CRD flow to the reactor. Furthermore, OMA 12
would only be necessary if the Isolation Condenser/CRD systems are
utilized for hot shutdown. If OMA 12 becomes necessary, the
licensee stated that they have assumed a 30-minute diagnosis period and
that the required time to perform the action is 15 minutes, while the
time available is 204 minutes, which provides a 159-minute margin.
3.17.5 Conclusion
Given the limited amount of combustible materials, ignition sources
and the volume of the space, it is unlikely that a fire would occur and
go undetected or unsuppressed by the suppression systems noted above,
or personnel, and damage the safe shutdown equipment. The low
likelihood of damage to safe shutdown equipment due to a fire in this
zone, combined with the ability of OMAs 1, 3,
5, 6, and 12 to manipulate the plant in the
event of a fire that damages safe shutdown equipment, provides adequate
assurance that safe shutdown capability is maintained.

[[Page 19812]]

3.18 TB-FZ-11E Turbine Bldg. Condenser Bay Area Elev. 0'-0''

3.18.1 Fire Prevention
The licensee has classified the fire loading in this fire zone as
low. The licensee also stated that this Fire Zone is procedurally
controlled as a transient combustible free area while the plant is
operating. This area is a high radiation area during plant operation
and is not normally accessed. The zone has an administrative fire
loading limit of less than 30 minutes as determined by the ASTM E119
time-temperature curve. The major combustibles in this area are cable
insulation (approximately 40% of loading) and plastic (approximately
59% of loading). Plastic grating, which is the largest plastic material
in this zone, is dispersed throughout this fire zone (not concentrated)
and has a low flame spread (less than 25).
3.18.2 Detection, Control, and Extinguishment
The licensee stated that a closed head automatic sprinkler and
spray systems protect the south end basement area and the hydrogen seal
oil unit. An exemption was granted from the requirements of Appendix R
Section III.G.2 in Safety Evaluations (SEs) dated March 24, 1986, and
June 25, 1990, for not having fixed fire detection in this area. The
primary basis for this exemption is the presence of the automatic wet
pipe sprinkler system, low fire loading and the 1-hour barrier
protection for safe shutdown circuits. Also, the flow alarm will notify
the control room of any sprinkler system activation. Since the
Condenser Bay is procedurally controlled as a transient combustible
free area in procedure OP-AA-201-009 while the plant is operating.
Extinguishment of a fire will be accomplished by the automatic fixed
suppression system and the plant fire brigade. A closed head automatic
sprinkler system was recently expanded to provide fire suppression over
the cables in cable trays in the northeast side of the condenser bay.
3.18.3 Preservation of Safe Shutdown Capability
The licensee stated that TB-FZ-11E has a ceiling height of at least
40' and an approximate floor area of 26427 square feet so it is
unlikely that smoke and heat would accumulate at the height of the safe
shutdown equipment and cause a failure due to fire damage.
3.18.4 OMAs Credited for a Fire in This Zone
3.18.4.1 OMA 1--Manually Trip 4160V 1D Breakers and Control
USS 1B2 & 1B3 Breakers Locally at LSP-1D
In order for OMA 1 to be necessary, the credited and
redundant cables would have to be damaged due to a fire. The licensee
stated that these cables are located in the same tray with additional
cables and are generally located approximately 40 feet above the floor.
With the exception of the cables themselves, there are no other
ignition sources or combustibles located near the cables.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 1 is available to manually
trip the 4160V 1D breakers and control USS 1B2 and the 1B3 480V
breakers locally at LSP-1D. The licensee also stated that they have
assumed a 10-minute diagnosis period and that the required time to
perform the action is 19 minutes while the time available is 45
minutes, which provides a 16-minute margin.
3.18.4.2 OMA 2--Read Condensate Storage Tank Local Level
Indicator LI-424-993
In order for OMA 2 to be necessary, damage to the primary
CST level indicator (5F-27) cable would have to occur due to a fire.
The licensee stated that this cable is located approximately 16 feet
above the floor. With the exception of the cables themselves, there are
no other ignition sources or combustibles located near the cables.
In the unlikely event that a fire does occur and damages the
primary CST level indicator, OMA 2 is available to locally
read CST level at the local indicator, LI-424-993, located at the CST.
The licensee also 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 73 minutes, which provides a 36-minute
margin.
3.18.4.3 OMA 3--Manually Control 1B3M Breaker at LSP-1B3
In order for OMA 3 to be necessary, the credited and
redundant cables would have to be damaged due to a fire. The licensee
stated that these cables are located in the same tray with additional
cables and are generally located approximately 40 feet above the floor.
With the exception of the cables themselves, there are no other
ignition sources or combustibles located near the cables.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 3 is available to manually
control the 1B3M breaker locally from LSP-1B3. The licensee also stated
that they have assumed a 10-minute diagnosis period and that the
required time to perform the action is 10 minutes while the time
available is 45 minutes, which provides a 25-minute margin.
3.18.4.4 OMA 4--Manually Control Condensate Transfer Pump 1-2
From LSP-1B32
In order for OMA 4 to be necessary, damage to the credited
and redundant cables for the Condensate Transfer Pump 1-2 would have to
be damaged due to a fire. The licensee stated that these cables are
located in the same tray with additional cables and are generally
located approximately 18 feet above the floor. With the exception of
the cables themselves, there are no other ignition sources or
combustibles located near the cables.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 4 is available to manually
control Condensate Transfer Pump 1-2 locally from LSP-1B32. The
licensee also stated that they have assumed a 10-minute diagnosis
period and that the required time to perform the action is 10 minutes
while the time available is 45 minutes, which provides a 25-minute
margin.
3.18.4.5 OMA 5--Manually Control Diesel Generator 2
from LSP-DG2
In order for OMA 5 to be necessary, damage to the credited
and redundant cables would have to occur due to a fire. The licensee
stated that the credited and redundant cables are located in separate
cable trays separated by a horizontal distance of at least 90 feet. The
licensee also stated that there are no ignition sources near the
redundant cables and that the primary ignition sources that could
affect the credited cables are the moisture separator drain pumps and
area sump pumps, which are located on the floor approximately 20 feet
horizontally and 17 feet vertically from the credited cables.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 5 is available to manually
control Emergency Diesel Generator 2 from LSP-DG2. The
licensee also stated that they have assumed a 10-minute diagnosis
period and that the required time to perform the action is 14 minutes
while the time available is 45 minutes, which provides a 21-minute
margin.

[[Page 19813]]

3.18.4.6 OMA 6--Manually Reclose Feeder Breaker MCC 1B32 at
USS 1B3
In order for OMA 6 to be necessary, power to USS 1B3 or
the 1B 4160V switchgear would have to be lost due to a fire. The
licensee stated that the cables that could cause the loss of USS 1B3
are located in the same tray with additional cables and are generally
located approximately 40 feet above the floor. With the exception of
the cables themselves, there are no other ignition sources or
combustibles located near the cables.
In the unlikely event that a fire does occur and causes a loss of
power to USS 1B3 or loss of the 1B 4160V switchgear, OMA 6 is
available to manually re-close Feeder Breaker MCC 1B32 at USS 1B3 due
to an under voltage trip. The licensee also stated that they have
assumed a 10-minute diagnosis period and that the required time to
perform the action is 6 minutes while the time available is 45 minutes,
which provides a 29-minute margin.
3.18.4.7 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that although the USSs powering the air
compressors are located 35 feet apart from each other, the power cables
are located in the same cable trays for at least 45 feet and that the
normal CRD flow control valve is a single component without a redundant
counterpart. Because of this, a manual bypass is provided to maintain
flow around the CRD flow control valves that fail closed upon loss of
instrument air or control cable damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while monitoring flow at FI-225-2, and close V-15-52
to establish CRD flow to the reactor. Furthermore, OMA 12
would only be necessary if the Isolation Condenser/CRD systems are
utilized for hot shutdown. If OMA 12 becomes necessary, the
licensee stated that they have assumed a 30-minute diagnosis period and
that the required time to perform the action is 15 minutes, while the
time available is 204 minutes, which provides a 159-minute margin.
3.18.4.8 OMA 16--Manually Trip Rx Recirculation Pumps at 4160V
Switchgear
In order for OMA 16 to be necessary, the credited and
redundant cables would have to be damaged due to a fire. The licensee
stated that the credited cables for tripping the recirculation pumps
are located in the same tray, or adjacent tray, with additional cables
and are generally located approximately 40 feet above the floor. With
the exception of the cables themselves, there are no other ignition
sources or combustibles located near the cables.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 16 is available to manually
trip Reactor Recirculation Pumps (``A,'' ``B,'' ``C,'' ``D'' and ``E'')
4160V Switchgear 1A and 1B. The licensee also stated that they have
assumed a 10-minute diagnosis period and that the required time to
perform the action is 13 minutes while the time available is 30
minutes, which provides a 7-minute margin.
3.18.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and large volume of the space, it is unlikely that a fire
would occur and go undetected or unsuppressed by the suppression system
noted above or personnel, and damage the safe shutdown equipment. The
low likelihood of damage to safe shutdown equipment due to a fire in
this zone, combined with the ability of OMAs 1, 2,
3, 4, 5, 6, 12, and
16 to manipulate the plant in the event of a fire that damages
safe shutdown equipment, provides adequate assurance that safe shutdown
capability is maintained.

3.19 TB-FZ-11F Turbine Bldg. Feedwater Pump Room Elev. 0'-0'' & 3'-6''

3.19.1 Fire Prevention
The licensee has classified the fire loading in this fire zone as
low. The licensee also stated that this area has an administrative fire
loading limit of less than 30 minutes as determined by the ASTM E119
time-temperature curve. The major combustible load consists of cable
insulation (approximately 15% of loading), lubricating oil
(approximately 39% of loading), rubber (approximately 21% of loading)
and plastics (approximately 17% of loading). The licensee states that
the majority of the combustible loading attributed to rubber and
plastic was due to the storage of hoses which are now no longer in the
area.
3.19.2 Detection, Control, and Extinguishment
The licensee stated that TB-FZ-11F has an area-wide thermal fire
detection system. Extinguishment of the fire will be accomplished by
the plant fire brigade.
3.19.3 Preservation of Safe Shutdown Capability
The licensee stated that TB-FZ-11F has a ceiling height of
approximately 16' in approximately 70% of the area and approximately
19'-6'' in the remainder of the area. With an approximate floor area of
5,650 square feet, it is unlikely that smoke and heat would accumulate
at the height of the safe shutdown equipment and cause a failure due to
fire damage.
3.19.4 OMAs Credited for a Fire in This Area
3.19.4.1 OMA 7--Align Fire Water to Isolation Condenser
In order for OMA 7 to be necessary, the loss of the ``B''
Train of power would have to occur due to fire damage. The loss of the
``B'' Train of power is attributed to the fact that the 125 VDC control
power could be lost to the 1D 4160V Switchgear or the 1D 4160V main
breaker could trip due to cables that traverse through this fire zone.
The licensee stated that the cables for the 125 VDC control power and
the control circuit for the 1D main breaker are contained in separate
conduits but are routed within approximately 6 inches of each other in
a portion of this zone and that the conduits are located approximately
5 to 18 feet above the floor. Additionally, the licensee stated that
the 125 VDC control cable leaves the zone through the east wall into
Fire Zone RB-FZ-1F2 while the 1D main breaker control cable continues
along the east wall near the floor through the remaining portion of
this zone and rises up to approximately 6 feet from the floor where it
exits the zone.
The licensee also stated that the primary ignition sources in the
area are the feedwater pumps and motors, which are located
approximately 10 feet from the conduits. Transient combustibles are
controlled by administrative procedures and although the accumulation
of transient combustibles along the east wall of the area could
potentially impact the cables, the majority of the conduits are routed
such that it would be unlikely that a fire in this area would adversely
impact the cables in the conduit. The ``A'' train of power is credited
and available for this fire zone. The redundant cable, ``C'' battery,
``C'' Distribution center, etc. are not located in this fire zone.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 7 is available

[[Page 19814]]

to manually open V-9-2099 and V-11-49 and close V-11-63 and V-11-41 to
align the fire water system for make-up water to Isolation Condenser
``B'' since there is no power (``B'' Train) available to the Condensate
Transfer System. The licensee also stated that they have assumed a 10-
minute diagnosis period and that the required time to perform the
action is 13 minutes while the time available is 45 minutes, which
provides a 22-minute margin.
3.19.4.2 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that although the USSs powering the air
compressors are located 35 feet apart from each other, the power cables
are located in the same cable trays for at least 45 feet and that the
normal CRD flow control valve is a single component without a redundant
counterpart. Because of this, a manual bypass is provided to maintain
flow around the CRD flow control valves that fail closed upon loss of
instrument air or control cable damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while monitoring flow at FI-225-2, and close V-15-52
to establish CRD flow to the reactor. Furthermore, OMA 12
would only be necessary if the Isolation Condenser/CRD systems are
utilized for hot shutdown. If OMA 12 becomes necessary, the
licensee stated that they have assumed a 30-minute diagnosis period and
that the required time to perform the action is 15 minutes, while the
time available is 204 minutes, which provides a 159-minute margin.
3.19.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and large volume of the space, it is unlikely that a fire
would occur and go undetected or unsuppressed by the thermal detection
system noted above or personnel, and damage the safe shutdown
equipment. The low likelihood of damage to safe shutdown equipment due
to a fire in this zone, combined with the ability of OMAs 7
and 12 to manipulate the plant in the event of a fire that
damages safe shutdown equipment, provides adequate assurance that safe
shutdown capability is maintained.

3.20 TB-FZ-11H Turbine Bldg. Demineralizer Tank and Steam Jet Air
Ejector Area Elev. 3'-6'' & 23'-6''

3.20.1 Fire Prevention
The licensee has classified the fire loading in this fire zone as
low. The licensee also stated that this area has an administrative fire
loading limit of less than 30 minutes as determined by the ASTM E119
time-temperature curve. The major combustibles are cable insulation
(approximately 23% of loading), ladders and other miscellaneous
plastics (approximately 55% of loading) and miscellaneous ordinary
combustibles.
3.20.2 Detection, Control, and Extinguishment
The licensee stated that TB-FZ-11H has a partial area thermal fire
detector system. The system alarms locally and in the control room.
Manual extinguishment of fire will be accomplished by the plant fire
brigade.
3.20.3 Preservation of Safe Shutdown Capability
The licensee stated that TB-FZ-11H has a ceiling height of
approximately 7'-0'', measured at the 3'-6'' elevation, and
approximately 19'-0'', measured at the 23'-6'' elevation with an
approximate floor area of 3,944 square feet and 4,366 square feet,
respectively, so it is unlikely that smoke and heat would accumulate at
the height of the safe shutdown equipment and cause a failure due to
fire damage.
3.20.4 OMAs Credited for a Fire in This Area
3.20.4.1 OMA 7--Align Fire Water to Isolation Condenser
In order for OMA 7 to be necessary, the loss of the ``B''
Train of power would have to occur due to fire damage. The loss of the
``B'' Train of power is attributed to the fact that the 125 VDC control
power could be lost to the 1D 4160V Switchgear or the 1D 4160V main
breaker could trip due to cables that traverse through this fire zone.
The licensee stated that the cables for the 125 VDC control power and
the control circuit for the 1D main breaker are contained in separate
conduits but are routed within approximately 6 inches of each other in
a portion of this zone and that the conduits are located approximately
5 to 6 feet above the floor. Additionally, the licensee stated that the
total length of the conduits in this area is approximately 20 feet.
The licensee also stated that there are no ignition sources in the
area and that combustible loading is limited since the area is a
stairway area. Transient combustibles are controlled by administrative
procedures and although the accumulation of transient combustibles
below the conduits could potentially impact the cables, it is unlikely
because the area is a stairway and part of the floor is blocked by a
large ventilation duct. The ``A'' train of power is credited and
available for this fire zone. The redundant cable, ``C'' battery, ``C''
Distribution center, etc. are not located in this fire zone.
In the unlikely event that a fire does occur and damages the
credited and redundant cables, OMA 7 is available to manually
open V-9-2099 and V-11-49 and close V-11-63 and V-11-41 to align the
fire water system for make-up water to Isolation Condenser ``B'' since
there is no power (``B'' Train) available to the Condensate Transfer
System. The licensee also stated that they have assumed a 10-minute
diagnosis period and that the required time to perform the action is 13
minutes while the time available is 45 minutes, which provides a 22-
minute margin.
3.20.4.2 OMA 12--Establish CRD Flow to Reactor
In order for OMA 12 to be necessary, a loss of instrument
air to the CRD flow control valve would have to occur due to fire
damage. The licensee stated that although the USSs powering the air
compressors are located 35 feet apart from each other, the power cables
are located in the same cable trays for at least 45 feet and that the
normal CRD flow control valve is a single component without a redundant
counterpart. Because of this, a manual bypass is provided to maintain
flow around the CRD flow control valves that fail closed upon loss of
instrument air or control cable damage.
In the unlikely event that a fire does occur and causes the normal
flow control valve to be unavailable due to a loss of instrument air or
cable damage, OMA 12 is available to manually open V-15-237,
throttle V-15-30 while monitoring flow at FI-225-2, and close V-15-52
to establish CRD flow to the reactor. Furthermore, OMA 12
would only be necessary if the Isolation Condenser/CRD systems are
utilized for hot shutdown. If OMA 12 becomes necessary, the
licensee stated that they have assumed a 30-minute diagnosis period and
that the required time to perform the action is 15 minutes, while the
time available is 204 minutes, which provides a 159-minute margin.
3.20.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and large volume of the space, it is

[[Page 19815]]

unlikely that a fire would occur and go undetected or unsuppressed by
the thermal detection system noted above or personnel, and damage the
safe shutdown equipment. The low likelihood of damage to safe shutdown
equipment due to a fire in this zone, combined with the ability of OMAs
7 and 12 to manipulate the plant in the event of a
fire that damages safe shutdown equipment, provides adequate assurance
that safe shutdown capability is maintained.

3.21 Feasibility of the Operator Manual Actions

This analysis postulates that OMAs may, in some scenarios, be
needed to assure safe shutdown 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. However, Exelon states that the OMAs
identified in its Phase 1 request were previously found acceptable in
fire protection SEs dated March 24, 1986 and June 25, 1990, and,
therefore, do not need to meet the reliability criteria specified in
NUREG-1852, ``Demonstrating the Feasibility and Reliability of Operator
Manual Actions in Response to Fire,'' dated October 2007. The NRC staff
finds that the SEs referenced by the licensee, in addition to the
feasibility review contained in this SE, provide the necessary
information to determine the feasibility and reliability of the OMAs.
3.21.1 Bases for Establishing Feasibility
Using NUREG-1852, the NRC staff has evaluated the feasibility
review provided by the licensee in the April 2, 2010, Response to
Request for Additional Information. For an OMA to be considered
feasible, the required actions must be proceduralized, any equipment
that is needed to implement the OMA is available, the environments in
which the OMA is to be performed must permit the action, and the time
taken to diagnose the need for the OMA and implement it (time required)
must be less than the time in which the OMA must be completed (time
available).
3.21.2 Feasibility
The feasibility review provided by the licensee documents 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. 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
abnormal operating procedure ABN-29, ``Plant Fires,'' is entered
whenever a fire or indication of a fire occurs on the main fire alarm
panel in the control room or at any local fire alarm panel. In addition
to dispatching a radio-equipped operator to the alarming location, ABN-
29 also directs that the fire brigade be dispatched whenever a fire
suppression system has actuated (sprinkler, deluge, Halon,
CO2) or a fire is confirmed. In addition, the licensee
stated that ABN-29 directs immediate entry into the FSP for the
affected fire area as soon as the existence of a fire is confirmed. The
licensee states that the following indications or symptoms are
considered examples of a confirmed fire:
Fire detection alarm and equipment malfunction indication
or alarms within the same area;
Fire pump start and either sprinkler flow alarm or deluge
flow alarm;
Gaseous suppression system actuation;
Report from the field of an actual smoke condition or
actual fire condition; or
Fire detection alarm with follow up confirmation by field
operator.
Entering the FSP means that the operator will review the FSP,
identify equipment that could be affected, identify equipment that will
be available, monitor plant equipment from the control room and
communicate with the fire brigade leader. Based on the symptoms
received in the control room and the feedback from the fire brigade
leader, the operator will decide using the procedure what mitigating
actions are necessary. In the event that a plant shutdown has occurred
before the FSP is entered, the operator will still enter the FSP based
on the fire and initiate the OMAs as appropriate. OMAs that are
considered ``prompt'' (i.e., those that must be done within 45 minutes
or less) are identified in both ABN-29 and in the applicable FSPs as an
item requiring immediate attention. The operators are trained to
perform prompt actions first and prioritize them based upon existing
plant conditions. The FSPs are based on the worst-case loss
considerations by assuming all fire damage occurs instantaneously and
thus all operator manual actions will be required. The use of the EOPs
in conjunction with the applicable FSPs will permit the use of any
mitigating system available first, and if a desired system is not
available, the FSP provides a contingency action to restore the system
or provide another means to perform the function. Operator training,
including simulator demonstrations and plant walk downs, has been
performed to ensure consistency in operator and team response for each
OMA.
The licensee evaluated several potential environmental concerns,
such as radiation levels, temperature/humidity conditions and the
ventilation configuration and fire effects that the operators may
encounter during certain emergency scenarios. The licensee's
feasibility review concluded that the operators performing the manual
actions would not be exposed to adverse or untenable conditions during
any particular operator manual action procedure or during the time to
perform the procedure. The licensee states that OMAs required for
achieving and maintaining hot shutdown conditions are not impacted by
environmental conditions associated with fires in the fire area
identified in the request. Each of the safe shutdown calculations that
provide the technical basis for the FSPs contains a timeline for
operator actions for the specific fire area. In addition, the licensee
stated that the equipment needed to implement OMAs remains available
and the fire areas remain accessible during or following the event.
In one instance, OMA 12, the licensee identified that an operator
may need to re-enter Fire Zone RB-FZ-1E (i.e., perform part of an OMA
in the affected fire zone) to manually manipulate three 2-inch CRD
System valves V-15-237, V-15-30, and V-15-52 that are physically
located within 4 feet of each other within the spray area of the
automatic localized fixed water spray deluge system installed in this
fire zone. An exemption was granted in SE dated June 25, 1990, for not
providing either additional separation from in-situ combustibles or
protection for CRD System valve V-15-30. This exemption was granted on
the basis that: (1) There are 204 minutes following a scram before this
action would need to be completed and this action and only requires 15
minutes to complete; (2) any fires in that area are unlikely to render
the valve inoperable; (3) the valves are within the spray area of an
automatic fixed water spray deluge system. Since valves V-15-237, V-15-
52, and V-15-30 are physically within 4 feet of each other the NRC
staff considers the technical basis of the exemption to be equally
valid for these two additional valves.
The licensee's analysis demonstrates that, for the expected
scenarios, the OMAs can be diagnosed and executed

[[Page 19816]]

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. Therefore, the OMAs included in this review are feasible
because there is adequate time available for the operator to perform
the required OMAs to achieve and maintain hot shutdown following a
postulated fire event. Table 2 summarizes the ``required'' versus
``available'' times for each OMA. The licensee has included any
diagnosis time as part of the required time for performing a particular
action. Where an action has multiple times or contingencies associated
with the ``available'' completion time, the lesser time is used. This
approach is considered to represent a conservative approach to
analyzing the timelines associated with each of the OMAs with regard to
the feasibility and reliability of the actions included in this
exemption. The licensee provided a discussion of the times and
circumstances associated with each of the actions in their March 3,
2009, and April 2, 2010, correspondence.

Table 2
----------------------------------------------------------------------------------------------------------------
Required Available Margin
OMA Fire area/zone of fire origin OMA location time (min) time (min) (min)
----------------------------------------------------------------------------------------------------------------
1................ TB-FA-26, TB-FZ-11B, TB-FZ- TB-FA-3B............... 29 45 16
11E.
------------------------------- --------------------------------------
TB-FZ-11C, TB-FZ-11D......... 34 45 11
2................ OB-FA-9, OB-FZ-6A, OB-FZ-8C, Yard................... 37 73 36
TB-FZ-11B, TB-FZ-11E.
3................ TB-FA-26, TB-FZ-11B, TB-FZ- CW-FA-14............... 20 45 25
11C, TB-FZ-11D, TB-FZ-11E.
4................ TB-FZ-11B, TB-FZ-11E......... MT-FA-12............... 20 45 25
5................ TB-FZ-11D, TB-FZ-11E......... DG-FA-17............... 24 45 21
6................ TB-FA-26, TB-FZ-11B, TB-FZ- CW-FA-14............... 16 45 29
11C, TB-FZ-11D, TB-FZ-11E.
7................ OB-FZ-6B, OB-FZ-8A, OB-FZ-8B, RB-FZ-1E............... 23 45 22
OB-FZ-8C, TB-FZ-11F, TB-FZ-
11H, CW-FA-14.
8................ OB-FZ-8C..................... OB-FZ-6A............... 38 60 22
9................ OB-FZ-6A..................... OB-FZ-6B............... 43 180 137
11............... RB-FZ-1E, RB-FZ-1G........... RB-FZ-1D............... 130 204 74
12............... RB-FZ-1D, RB-FZ-1F5, TB-FA- RB-FZ-1E............... 45 204 159
3A, OB-FZ-6A, OB-FZ-6B, OB-
FZ-8A, OB-FZ-8B, OB-FZ-8C,
OB-FA-9, TB-FA-26, TB-FZ-
11B, TB-FZ-11C, TB-FZ-11D,
TB-FZ-11E, TB-FZ-11F, TB-FZ-
11H, CW-FA-14.
------------------------------- --------------------------------------
OB-FZ-10A.................... 48 204 156
------------------------------- --------------------------------------
RB-FZ-1E, RB-FZ-1G........... 130 204 74
13............... RB-FZ-1F3.................... RB-FZ-1F2.............. 65 204 139
16............... TB-FZ-11B, TB-FZ-11E, OB-FZ- TB-FZ-11C.............. 23 30 7
8C.
----------------------------------------------------------------------------------------------------------------

The NRC staff reviewed the required OMA completion time limits
versus the time before the action becomes critical to safely shutting
down the unit as presented in the feasibility analyses. The NRC staff
recognizes that, in some cases, the time required neared the time
available for an OMA. The NRC staff, however, also recognizes that
there are conservatisms built in to these time estimates such as adding
in the entire time assumed to diagnose the need for an OMA where in
reality, the actual time take would likely be less.
The NRC staff notes that, in one case, an OMA must be completed
within 30 minutes (i.e., it is considered a prompt action). This action
is identified as OMA 16 and requires an operator to manually
trip the Reactor Recirculation Pumps ``A,'' ``B,'' ``C,'' ``D'' and
``E'' at the 4160V Switchgear 1A and 1B. The action may be required as
a result of fire in OB-FZ-8C, TB-FZ-11B, or TB-FZ-11E. The symptom for
this action is the inability to trip the Recirculation Pumps from the
control room and this is detected using the associated pump breaker
indicating lights, alarms and flow indications. The Fire Support
Procedures direct the operator to trip the pumps using the pump control
switches or the Recirculation Pump Trip circuitry (two trip coils for
pumps). If both of these methods fail on one or more pumps, the
guidance is given to trip the pumps from the 4160V Switchgear 1A and 1B
located outside the control room in Fire Area TB-FZ-11C. Only one
operator would be required and it would take approximately 13 minutes
for access to the area and to perform the action of tripping the
breakers. Given the low complexity of this action, the NRC staff finds
that there is a sufficient amount of time available to complete the
proposed OMAs.

3.22 Summary of Defense-in-Depth and Operator Manual Actions

In summary, the defense-in-depth concept for a fire in the fire
areas discussed above provides a level of safety that limits the
occurrence of fires and results in rapid detection, control and
extinguishment of fires that do occur and the protection of structures,
systems, and components important to safety. It should be understood
that the OMAs are a fall back in the unlikely event that the fire
protection defense-in-depth features are insufficient. In most cases,
there is no credible fire scenario that would necessitate the
performance of these OMAs. As discussed 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 safe shutdown capability in the event of a fire in
the analyzed fire areas.

[[Page 19817]]

3.23 Authorized by Law

This exemption would allow Oyster Creek to rely on OMAs, in
conjunction with the other installed fire protection features, to
ensure that at least one means of achieving and maintaining hot
shutdown remains available during and following a postulated fire
event, as part of its FPP, 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.

3.24 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 hot
shutdown remains available during and following a postulated fire
event. Based on the above evaluation, the NRC staff finds that the
plant features, as described in the March 3, 2009, submittal, as
supplemented by letter dated April 2, 2010, should limit the occurrence
and impacts of any fire that may occur. This, combined with the ability
of the OMAs to place and maintain the plant in a safe condition in the
event of a fire that does damage safe shutdown equipment, provides
adequate protection of public health and safety. Therefore, there is no
undue risk to public health and safety.

3.25 Consistent With Common Defense and Security

This exemption would allow Oyster Creek 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
change, to the operation of the plant, has no relation to security
issues nor does it diminish the level of safety from what was intended
by the requirements of III.G.2. Therefore, the common defense and
security is not diminished by this exemption.

3.26 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 hot shutdown remains
available during and following a postulated fire event. While the
licensee does not comply with the explicit requirements of III.G.2,
specifically, they do meet the underlying purpose of 10 CFR part 50,
Appendix R, and Section III.G as a whole. Therefore, special
circumstances exist that warrant the issuance of this exemption as
required by 10 CFR 50.12(a)(2)(ii).

4.0 Conclusion

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 Exelon an exemption from the requirements of Section III.G.2 of
Appendix R of 10 CFR part 50, to utilize the OMAs discussed above at
Oyster Creek.
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 (74 FR 36274).
This exemption is effective upon issuance.

Dated at Rockville, Maryland, this 30th day of March 2011.
For the Nuclear Regulatory Commission.
Joseph G. Giitter,
Director, Division of Operating Reactor Licensing, Office of Nuclear
Reactor Regulation.
[FR Doc. 2011-8405 Filed 4-7-11; 8:45 am]
BILLING CODE 7590-01-P