[Federal Register Volume 76, Number 67 (Thursday, April 7, 2011)]
[Notices]
[Pages 19488-19510]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-8318]
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NUCLEAR REGULATORY COMMISSION
[Docket No. 50-219; NRC-2010-0200]
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 must provide the
established level of protection as intended by Section III.G of 10 CFR
Part 50, Appendix R.
By letter dated March 4, 2009, ``Request for Exemption from 10 CFR
50, Appendix R, Section III.G, `Fire Protection of Safe Shutdown
Capability (Phase 2)' '' available at Agencywide Documents Access and
Management System (ADAMS), Accession No. ML090640225, and supplemented
by letter dated April 2, 2010, ``Response to Request for Additional
Information Request for Exemption from 10 CFR Part 50, Appendix R,
Section III.G, `Fire Protection of Safe Shutdown Capability' '' (ADAMS
Accession No. 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 22 plant 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, TB-FZ-
11H, and Yard. The 22 plant areas noted above 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).
[[Page 19489]]
In their March 4, 2009, and April 2, 2010, letters, the licensee
discussed financial implications associated with plant modifications
that may be necessary to comply with the regulation.
Section 50.12(a)2(iii) of 10 CFR 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. Section 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 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
----------------------------------------------------------------------------------------------------------------
OMA
Area of fire origin Area name Actions
----------------------------------------------------------------------------------------------------------------
1................... CW-FA-14................. Circulatory Water Intake. Provide makeup control 17
air to the accumulator
for V-11-34 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
2................... OB-FA-9.................. Office Building (Bldg.) Provide makeup control 17
Elev. 23'-6'', 35'-0'', air to the accumulator
46'-6''. for V-11-34 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
3................... OB-FZ-6A................. Office Bldg. ``A'' 480V Provide makeup control 17
Switchgear (SWGR) Room air to the accumulator
Elev. 23'-6''. for V-11-34 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
4................... OB-FZ-6B................. Office Bldg. ``B'' 480V Provide makeup control 18
SWGR Room Elev. 23'-6''. air to the accumulator
for V-11-36 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
5................... OB-FZ-8A................. Office Bldg. Reactor Provide makeup control 17
Recirculation Motor air to the accumulator
Generator (MG) Set Room for V-11-34 for the
Elev. 23'-6''. Isolation Condenser
makeup line due to the
loss of instrument air.
6................... OB-FZ-8B................. Office Bldg. Mechanical Provide makeup control 17
Equipment Room Elev. 35'- air to the accumulator
0''. for V-11-34 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
7................... OB-FZ-8C................. Office Bldg. A/B Battery Provide makeup control 17
Room, Tunnel and air to the accumulator
Electrical Tray Room for V-11-34 for the
Elev. 35'-0''. Isolation Condenser
makeup line due to the
loss of instrument air.
8................... OB-FZ-10A................ Office Bldg. Monitor and Provide makeup control 18
Change Room Area and air to the accumulator
Operations Support Area for V-11-36 for the
Elev. 35'-0'' & 46'-6''. Isolation Condenser
makeup line due to the
loss of instrument air.
9................... RB-FZ-1D................. Reactor Bldg. Elev. 51'- Provide makeup control 17
3''. air to the accumulator
for V-11-34 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
10.................. RB-FZ-1E................. Reactor Building Elev. Provide makeup control 17
23'-6''. air to the accumulator
for V-11-34 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
11.................. RB-FZ-1F3................ Reactor Bldg. Northwest Provide makeup control 17
Corner Elev.-19'-6''. air to the accumulator
for V-11-34 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
12.................. RB-FZ-1F5................ Reactor Bldg. Torus Room Provide makeup control 17
Elev. -19'-6''. air to the accumulator
for V-11-34 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
[[Page 19490]]
13.................. RB-FZ-1G................. Reactor Bldg. Shutdown Provide makeup control 17
Cooling Room Elev. 38'- air to the accumulator
0'' & 51'-3''. for V-11-34 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
14.................. TB-FA-3A................. Turbine Bldg. 4160V Provide makeup control 17
Emergency SWGR Vault 1C air to the accumulator
Elev. 23'-6''. for V-11-34 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
15.................. TB-FA-26................. Turbine Bldg. 125V DC Trip Field Breakers for 1
Battery Room C Elev. 23'- Recirculation Pumps MG
6''. Set so that the Fuel
Zone Level Indicators
can be used.
Provide Fire Water to 2
Isolation Condenser
shell by operating
valves V-9-2099, V-11-
49, V-11-63 and V-11-41
due to loss of power
(contingency action).
Manually control 480V USS 3
1B2 Breakers for control
rod drive (CRD) Pump
NC08B and 1B2M from
Remote Shutdown Panel
due to control circuit
damage.
Manually open V-11-36 to 7
provide makeup to
Isolation Condenser due
to loss of power
(contingency action).
Check Isolation Condenser 8
Shell level locally due
to loss of power
(contingency action).
Provide makeup control 18
air to the accumulator
for V-11-36 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
16.................. TB-FZ-11B................ Turbine Bldg. Lube Oil Manually control 480V 3
Storage, Purification Unit Substation (USS)
and Pumping Area Elev. 1B2 Breakers for CRD
0'[dash]0'', 27'-0'', Pump NC08B and 1B2M from
and 36'-0''. Remote Shutdown Panel
due to control circuit
damage.
Provide makeup control 18
air to the accumulator
for V-11-36 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
17.................. TB-FZ-11C................ Turbine Bldg. SWGR Room Trip Field Breakers for 1
1A and 1B Elev. 23'-6''. Recirculation Pumps MG
Set so that the Fuel
Zone Level Indicators
can be used.
Provide Fire Water to 2
Isolation Condenser
shell by operating
valves V-9-2099, V-11-
49, V-11-63 and V-11-41
due to loss of power
(contingency action).
Manually control 480V USS 3
1B2 Breakers for CRD
Pump NC08B and 1B2M from
Remote Shutdown Panel
due to control circuit
damage.
Manually open V-11-36 to 7
provide makeup to
Isolation Condenser due
to loss of power
(contingency action).
Check Isolation Condenser 8
Shell level locally due
to loss of power
(contingency action).
Provide makeup control 18
air to the accumulator
for V-11-36 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
18.................. TB-FZ-11D................ Turbine Bldg. Basement Trip Field Breakers for 1
Floor South End Elev. 3'- Recirculation Pumps MG
6''. Set so that the Fuel
Zone Level Indicators
can be used.
Provide Fire Water to 2
Isolation Condenser
shell by operating
valves V-9-2099, V-11-
49, V-11-63 and V-11-41
due to loss of power
(contingency action).
Manually control 480V USS 3
1B2 Breakers for CRD
Pump NC08B and 1B2M from
Remote Shutdown Panel
due to control circuit
damage.
Manually open V-11-36 to 7
provide makeup to
Isolation Condenser due
to loss of power
(contingency action).
Check Isolation Condenser 8
Shell level locally due
to loss of power
(contingency action).
Provide makeup control 18
air to the accumulator
for V-11-36 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
19.................. TB-FZ-11E................ Turbine Bldg. Condenser Manually control 480V USS 3
Bay Area Elev. 0'-0''. 1B2 Breakers for CRD
Pump NC08B and 1B2M from
Remote Shutdown Panel
due to control circuit
damage.
Provide makeup control 18
air to the accumulator
for V-11-36 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
20.................. TB-FZ-11F................ Turbine Bldg. Feedwater Provide makeup control 18
Pump Room Elev. 0'-0'' & air to the accumulator
3'-6''. for V-11-36 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
21.................. TB-FZ-11H................ Turbine Bldg. Provide makeup control 18
Demineralizer Tank and air to the accumulator
Steam Jet Air Ejector for V-11-36 for the
Area Elev. 3'-6'' & 23'- Isolation Condenser
6''. makeup line due to the
loss of instrument air.
[[Page 19491]]
22.................. Yard..................... Office Bldg. Roof, Manually open V-15-237, 9
Turbine Bldg. Roof, and throttle V-15-30 while
All Remaining Outside monitoring flow at FI-
Areas. 225-2 and close V-15-52
to establish CRD flow to
Reactor due to the loss
of instrument air to the
CRD Flow Control Valve.
Provide makeup control 17
air to the accumulator
for V-11-34 for the
Isolation Condenser
makeup line due to the
loss of instrument air.
----------------------------------------------------------------------------------------------------------------
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 22 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 and OB-FZ-6B have been classified as
having a 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, 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 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 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 Table 2 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 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.
[[Page 19492]]
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 likely 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 17--Provide Makeup Air to Isolation Condenser
Valve V-11-34 Accumulator
In order for OMA 17 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-34 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 OMA 17 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-34 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the main steam isolation valves (MSIVs) will close,
as well as multiple air-operated valves changing state. Additionally,
reactor pressure vessel (RPV) level indication is also available for
all fire areas or zones. All of these indications would help the
operator diagnose the loss of instrument air and initiate mitigating
procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 17 is available
to provide makeup control air to the accumulator for V-11-34 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 17 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-minute margin.
3.1.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and open nature of the area, it is unlikely that a fire would
occur and go undetected or unsuppressed by the 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 17 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 OB-FA-9 Office Bldg. Elev. 23'-6'', 35'-0'', 46'-6'',
3.2.1 Fire Prevention
The licensee has classified the fire loading in this fire area as
low. The licensee also stated 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 a 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 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 17--Provide Makeup Air to Isolation Condenser
Valve V-11-34 Accumulator
In order for OMA 17 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-34 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 OMA 17 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-34 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time. This scenario is unlikely for this particular area since
the plant would likely reach cold shutdown before the action is
required.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a
[[Page 19493]]
panel in the control room for instrument air pressure. If all of these
instruments are not available, then ABN-35 further indicates that the
control rods will start to drift into the core and the MSIVs will
close, as well as multiple air-operated valves changing state.
Additionally, RPV level indication will not be compromised by a fire in
any zone or area. All of these indications would help the operator
diagnose the loss of instrument air and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 17 is available
to provide makeup control air to the accumulator for V-11-34 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 17 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-minute margin.
3.2.5 Conclusion
Given the limited amount of combustible materials, ignition
sources, and 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 OMA 17 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 stated that the fire loading in this zone is moderate
and that there is an administrative controls program in place to limit
additional combustible materials and sources of ignition. The licensee
also stated that the main combustibles in this area are cable
insulation (approximately 81% of loading) and Dow Corning 561 Silicon
transformer liquid (approximately 15% of loading). 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 17--Provide Makeup Air to Isolation Condenser
Valve V-11-34 Accumulator
In order for OMA 17 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-34 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 OMA 17 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-34 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 17 is available
to provide makeup control air to the accumulator for V-11-34 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 17 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-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 OMA 17 to
manipulate the plant in the event of a fire that damages safe shutdown
equipment, provides adequate assurance that safe shutdown capability is
maintained.
3.4 OB-FZ-6B Office Building ``B'' 480V SWGR Room Elev. 23'-6'',
3.4.1 Fire Prevention
The licensee stated that the fire loading in this zone is moderate
and that there is an administrative controls program in place to limit
additional combustible materials and sources of ignition. The licensee
also stated that 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). 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
[[Page 19494]]
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 18--Provide Makeup Air to Isolation Condenser
Valve V-11-36 Accumulator
In order for OMA 18 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-36 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 OMA 18 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-36 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 18 is available
to provide makeup control air to the accumulator for V-11-36 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 18 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-minute margin.
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 area, combined with the ability of OMA 18 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 analysis. The licensee
stated that the fire loading in this zone is low and that there is an
administrative controls program in place to limit additional
combustible materials and sources of ignition. The licensee also stated
that 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 This Area
3.5.4.1 OMA 17--Provide Makeup Air to Isolation Condenser
Valve V-11-34 Accumulator
In order for OMA 17 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-34 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 OMA 17 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-34 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time. This scenario is unlikely for this particular area since
the plant would likely reach cold shutdown before the action is
required.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 17 is available
to provide makeup control air to the accumulator for V-11-34 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 17
[[Page 19495]]
becomes necessary, the licensee stated that they have assumed a 30-
minute diagnosis period and that the required time to perform the
action is 26 minutes, while the time available is 300 minutes, which
provides a 244-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 in this zone, combined with the ability of OMA 17 to
manipulate the plant in the event of a fire that damages safe shutdown
equipment, provides adequate assurance that safe shutdown capability is
maintained.
3.6 OB-FZ-8C Office Bldg. A/B Battery Room, Tunnel and Electrical Tray
Room Elev. 35'-0''
3.6.1 Fire Prevention
The licensee stated that the fire loading in this zone is low and
that there is an administrative controls program in place to limit
additional combustible materials and sources of ignition. The licensee
also stated that 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 17--Provide Makeup Air to Isolation Condenser
Valve V-11-34 Accumulator
In order for OMA 17 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-34 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 OMA 17 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-34 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time. This scenario is unlikely for this particular area since
the plant would likely reach cold shutdown before the action is
required.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 17 is available
to provide makeup control air to the accumulator for V-11-34 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 17 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-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 OMA 17 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'-0'' & 46'-6''
3.7.1 Fire Prevention
The licensee stated that the fire loading in this zone is low and
that there is an administrative controls program in place to limit
additional combustible materials and sources of ignition. The licensee
also stated that the major combustibles in this area are cable
insulation (approximate 27% of loading), rubber flooring (approximately
31% of loading), miscellaneous plastics (approximately 17% of loading)
and protective clothing supplies (approximately 20% of loading).
However, since the protective clothing 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.
[[Page 19496]]
3.7.4 OMAs Credited for a Fire in This Area
3.7.4.1 OMA 18--Provide Makeup Air to Isolation Condenser
Valve V-11-36 Accumulator
In order for OMA 18 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-36 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 OMA 18 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-36 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time. This scenario is unlikely for this particular area since
the plant would likely reach cold shutdown before the action is
required.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 18 is available
to provide makeup control air to the accumulator for V-11-36 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 18 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 29 minutes, while the time available is 300
minutes, which provides a 241-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
18 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 stated that the fire loading in this zone is low and
that there is an administrative controls program in place to limit
additional combustible materials and sources of ignition. The licensee
also stated that 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 tray 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 Area
3.8.4.1 OMA 17--Provide Makeup Air to Isolation Condenser
Valve V-11-34 Accumulator
In order for OMA 17 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-34 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 OMA 17 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-34 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 17 is available
to provide makeup control air to the accumulator for V-11-34 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 17 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-minute margin.
[[Page 19497]]
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 area, combined with the
ability of OMA 17 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'-3''
3.9.1 Fire Prevention
The licensee stated that the fire loading in this zone is low and
that there is an administrative controls program in place to limit
additional combustible materials and sources of ignition. The licensee
also stated that 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 tray 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 17--Provide Makeup Air to Isolation Condenser
Valve V-11-34 Accumulator
In order for OMA 17 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-34 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 OMA 17 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-34 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 17 is available
to provide makeup control air to the accumulator for V-11-34 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 17 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-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 OMA 17 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'-6''
3.10.1 Fire Prevention
The licensee stated that the fire loading in this zone is low and
that there is an administrative controls program in place to limit
additional combustible materials and sources of ignition. The licensee
also stated that 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 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 17--Provide Makeup Air to Isolation Condenser
Valve V-11-34 Accumulator
In order for OMA 17 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-34 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 OMA 17 connects a high
pressure air cylinder to
[[Page 19498]]
the accumulator of Condensate Transfer System valve V-11-34 and that
these air-operated valves are used to control makeup to the isolation
condensers. Each valve is provided with an air accumulator that
provides a minimum of six full cycles. As a result, this OMA is only
necessary to ensure long-term operation of these valves and makeup to
the isolation condensers. Further, this OMA would only be necessary if
the plant had to remain in hot shutdown for an extended time. This
scenario is unlikely for this particular area since the plant would
likely reach cold shutdown before the action is required.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 17 is available
to provide makeup control air to the accumulator for V-11-34 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 17 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-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
area, combined with the ability of OMA 17 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 stated that the fire loading in this zone is low and
that there is an administrative controls program in place to limit
additional combustible materials and sources of ignition. The licensee
also stated that 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 detection or
suppression systems. However, due to the limited combustible loading
and the nature of the combustibles, 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 11,450 square feet and a ceiling height of
approximately 41'-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 17--Provide Makeup Air to Isolation Condenser
Valve V-11-34 Accumulator
In order for OMA 17 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-34 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 OMA 17 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-34 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time. This scenario is unlikely for this particular area since
the plant would likely reach cold shutdown before the action is
required.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 17 is available
to provide makeup control air to the accumulator for V-11-34 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 17 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-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 area, combined with the
ability of OMA 17 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 stated that the fire loading in this zone is low and
that there is an administrative controls program in place to limit
additional
[[Page 19499]]
combustible materials and sources of ignition. The licensee also stated
that 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 1,609 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 Area
3.12.4.1 OMA 17--Provide Makeup Air to Isolation Condenser
Valve V-11-34 Accumulator
In order for OMA 17 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-34 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 OMA 17 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-34 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time. This scenario is unlikely for this particular area since
the plant would likely reach cold shutdown before the action is
required.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 17 is available
to provide makeup control air to the accumulator for V-11-34 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 17 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-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
area, combined with the ability of OMA 17 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 stated that the fire loading in this area is low and
that there is an administrative controls program in place to limit
additional combustible materials and sources of ignition. The licensee
also stated that 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 17--Provide Makeup Air to Isolation Condenser
Valve V-11-34 Accumulator
In order for OMA 17 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-34 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 OMA 17 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-34 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time. This scenario is unlikely for this particular area since
the plant would likely reach cold shutdown before the action is
required.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally,
[[Page 19500]]
RPV level indication will not be compromised by a fire in any zone or
area. All of these indications would help the operator diagnose the
loss of instrument air and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 17 is available
to provide makeup control air to the accumulator for V-11-34 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 17 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-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 17 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 stated that the fire loading in this area is moderate
and that there is an administrative controls program in place to limit
additional combustible materials and sources of ignition. The licensee
also stated that 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.
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 fire safe shutdown component and cable located in this
fire area is associated with the ``C'' battery.
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
the discussion of OMAs 1, 2, 3, 7,
8, and 18.
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, 2, 3, 7, 8, and
18 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 stated that the fire loading in this zone is high and
that there is an administrative controls program in place to limit
additional combustible materials and sources of ignition. The licensee
also stated that the major combustibles in this area are lubricating
oil (approximately 99% of loading) and cable insulation (approximately
0.3% of loading).
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 3175 square feet.
3.15.4 OMAs Credited for a Fire in This Zone
3.15.4.1 OMA 3--Manually Control 480V USS 1B2 Breakers for CRD
Pump at Remote Shutdown Panel
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 480V USS 1B2 Breakers for CRD Pump NC08B and 1B2M from the
Remote Shutdown Panel due to control circuit damage. 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 180 minutes, which provides a 142-minute margin.
3.15.4.2 OMA 18--Provide Makeup Air to Isolation Condenser
Valve V-11-36 Accumulator
In order for OMA 18 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-36 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
[[Page 19501]]
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 OMA 18 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-36 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time. This scenario is unlikely for this particular area since
the plant would likely reach cold shutdown before the action is
required.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 18 is available
to provide makeup control air to the accumulator for V-11-36 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 18 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-minute margin.
3.15.5 Conclusion
Although the fire loading 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 3 and 18 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 stated that the fire loading in this zone is low and
that there is an administrative controls program in place to limit
additional combustible materials and sources of ignition. The licensee
also stated that 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
(except in the small caged area located to the east of Fire Area TB-FA-
3A) installed.
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 Area
3.16.4.1 OMA 1--Trip Field Breakers for Recirculation Pumps MG
Set
In order for OMA 1 to be necessary, damage to the 1A and
1B 4160V Switchgear Cabinets and the ``C'' Battery distribution panel,
or the associated control wiring, would have to occur due to a fire and
prevent tripping of the 4160V motor-generator set breakers. 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 equipment, OMA 1 is available to trip
the field breakers for the recirculation pumps motor-generator set so
that the Fuel Zone Level Indicators can be used. The licensee also
stated that they have assumed a 10-minute diagnosis period and that the
required time to perform the action is 8 minutes while the time
available is 30 minutes, which provides a 12-minute margin.
3.16.4.2 OMA 2--Align Fire Water to Isolation Condenser
In order for OMA 2 to be necessary, loss of the ``B''
train of power would have to occur due to a fire causing a loss of both
condensate transfer pumps. The licensee stated that this OMA is
dependent on the LSP-1D OMA, which was included in the licensee's Phase
1 request, and would not be required unless the OMA at the LSP-1D is
required and access is not immediately available. As such, this OMA is
considered a contingency action. The licensee also stated that these
cables are located in the same tray with additional cables and are
generally located at least 17 feet above the floor and 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 2 is available to provide
fire water to the isolation condenser shell by operating valves V-9-
2099, V-11-49, V-11-63, and V-11-41 due to loss of power. 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.
3.16.4.3 OMA 3--Manually Control 480V USS 1B2 Breakers for CRD
Pump at Remote Shutdown Panel
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
[[Page 19502]]
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 480V USS 1B2 Breakers for CRD Pump NC08B and 1B2M from the
Remote Shutdown Panel due to control circuit damage. 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 180 minutes, which provides a 142-minute margin.
3.16.4.4 OMA 7--Provide Makeup to Isolation Condenser via V-
11-36
In order for OMA 7 to be necessary, loss of the ``B''
train of power would have to occur due to a fire causing a loss of both
condensate transfer pumps. The licensee stated that this OMA is
dependent on the LSP-1D OMA, which was included in the licensee's Phase
1 request, and would not be required unless the OMA at the LSP-1D is
required and access is not immediately available. As such, this OMA is
considered a contingency action. The licensee also stated that these
cables are located in the same tray with additional cables and are
generally located at least 17 feet above the floor and 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 7 is available to manually
open V-11-36 to provide makeup to Isolation Condenser due to loss of
power. The licensee also stated that they have assumed a 10-minute
diagnosis period and that the required time to perform the action is 16
minutes while the time available is 45 minutes, which provides a 19-
minute margin.
3.16.4.5 OMA 8--Locally Check Isolation Condenser Shell Level
In order for OMA 8 to be necessary, loss of the ``B''
train of power would have to occur due to a fire causing a loss of both
condensate transfer pumps. The licensee stated that this OMA is
dependent on the LSP-1D OMA, which was included in the licensee's Phase
1 request, and would not be required unless the OMA at the LSP-1D is
required and access is not immediately available. As such, this OMA is
considered a contingency action. The licensee also stated that these
cables are located in the same tray with additional cables and are
generally located at least 17 feet above the floor and 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 8 is available to check the
isolation condenser shell level locally due to loss of power. The
licensee also stated that they have assumed a 10-minute diagnosis
period and that the required time to perform the action is 16 minutes
while the time available is 45 minutes, which provides a 19-minute
margin.
3.16.4.6 OMA 18--Provide Makeup Air to Isolation Condenser
Valve V-11-36 Accumulator
In order for OMA 18 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-36 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 OMA 18 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-36 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time. This scenario is unlikely for this particular area since
the plant would likely reach cold shutdown before the action is
required.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the main MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 18 is available
to provide makeup control air to the accumulator for V-11-36 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 18 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-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 area, combined with the ability of OMAs
1, 2, 3, 7, 8, and
18 to manipulate the plant in the event of a fire that damages
safe shutdown equipment, provide adequate assurance that safe shutdown
capability is maintained.
3.17 TB-FZ-11D Turbine Bldg. Basement Floor South End Elev. 3'-6''
3.17.1 Fire Prevention
The licensee stated that the fire loading in this zone is low and
that there is an administrative controls program in place to limit
additional combustible materials and sources of ignition. The licensee
also stated that 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
[[Page 19503]]
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--Trip Field Breakers for Recirculation Pumps MG
Set
In order for OMA 1 to be necessary, damage to the 1A and
1B 4160V Switchgear Cabinets and the ``C'' Battery distribution panel,
or the associated control wiring, would have to occur due to a fire and
prevent tripping of the 4160V MG set breakers. 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 equipment, OMA 1 is available to trip
the field breakers for the recirculation pumps MG Set so that the fuel
zone level indicators can be used. The licensee also stated that they
have assumed a 10-minute diagnosis period and that the required time to
perform the action is 8 minutes while the time available is 30 minutes,
which provides a 12-minute margin.
3.17.4.2 OMA 2--Align Fire Water to Isolation Condenser
In order for OMA 2 to be necessary, loss of the ``B''
train of power would have to occur due to a fire causing a loss of both
condensate transfer pumps. The licensee stated that this OMA is
dependent on the LSP-1D OMA, which was included in the licensee's Phase
1 request, and would not be required unless the OMA at the LSP-1D is
required and access is not immediately available. As such, this OMA is
considered a contingency action. In addition, 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 2 is available to provide
fire water to the isolation condenser shell by operating valves V-9-
2099, V-11-49, V-11-63, and V-11-41 due to loss of power. 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.
3.17.4.3 OMA 3--Manually Control 480V USS 1B2 Breakers for CRD
Pump at Remote Shutdown Panel
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 480V USS 1B2 Breakers for CRD Pump NC08B and 1B2M from the
Remote Shutdown Panel due to control circuit damage. 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 180 minutes, which provides a 142-minute margin.
3.17.4.4 OMA 7--Provide Makeup to Isolation Condenser via V-
11-36
In order for OMA 7 to be necessary, loss of the ``B''
train of power would have to occur due to a fire causing a loss of both
condensate transfer pumps. The licensee stated that this OMA is
dependent on the LSP-1D OMA, which was included in the licensee's Phase
1 request, and would not be required unless the OMA at the LSP-1D is
required and access is not immediately available. As such, this OMA is
considered a contingency action. In addition, 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
[[Page 19504]]
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 7 is available to manually
open V-11-36 to provide makeup to Isolation Condenser due to loss of
power. The licensee also stated that they have assumed a 10-minute
diagnosis period and that the required time to perform the action is 16
minutes while the time available is 45 minutes, which provides a 19-
minute margin.
3.17.4.5 OMA 8--Locally Check Isolation Condenser Shell Level
In order for OMA 8 to be necessary, loss of the ``B''
train of power would have to occur due to a fire causing a loss of both
condensate transfer pumps. The licensee stated that this OMA is
dependent on the LSP-1D OMA, which was included in the licensee's Phase
1 request, and would not be required unless the OMA at the LSP-1D is
required and access is not immediately available. As such, this OMA is
considered a contingency action. In addition, 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 8 is available to check the
isolation condenser shell level locally due to loss of power. The
licensee also stated that they have assumed a 10-minute diagnosis
period and that the required time to perform the action is 16 minutes
while the time available is 45 minutes, which provides a 19-minute
margin.
3.17.4.6 OMA 18--Provide Makeup Air to Isolation Condenser
Valve V-11-36 Accumulator
In order for OMA 18 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-36 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 OMA 18 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-36 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time. This scenario is unlikely for this particular area since
the plant would likely reach cold shutdown before the action is
required.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 18 is available
to provide makeup control air to the accumulator for V-11-36 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 18 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-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, 2,
3, 7, 8, and 18 to manipulate the
plant in the event of a fire that damages safe shutdown equipment,
provides adequate assurance that safe shutdown capability is
maintained.
3.18 TB-FZ-11E Turbine Bldg. Condenser Bay Area Elev. 0'-''0
3.18.1 Fire Prevention
The licensee stated that the fire loading in this zone is low and
that there is an administrative controls program in place to limit
additional combustible materials and sources of ignition. The licensee
also stated that the major combustibles in this area are cable
insulation (approximately 40% of loading) and plastic (approximately
59% of loading). The grating, which is the largest plastic material in
this area, is dispersed throughout this fire zone (not concentrated)
and has a low flame spread (less than 25). The licensee also stated
that this Fire Zone is procedurally controlled as a transient
combustible free area while the plant is operating and that this area
is a high
[[Page 19505]]
radiation area during plant operation and is not normally accessed.
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 dated March 24, 1986, and June
25, 1990, for not having fixed fire detection in this area. The primary
basis for this exemption was the presence of the automatic wet pipe
sprinkler system and low fire loading. The Condenser Bay is
procedurally controlled as a transient combustible free area in while
the plant is operating. If a fire did occur, the flow alarm would
notify the control room of any sprinkler system activation.
Extinguishment of a fire can 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 26,427 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 3--Manually Control 480V USS 1B2 Breakers for CRD
Pump at Remote Shutdown Panel
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 480V USS 1B2 Breakers for CRD Pump NC08B and 1B2M from the
Remote Shutdown Panel due to control circuit damage. 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 180 minutes, which provides a 142-minute margin.
3.18.4.2 OMA 18--Provide Makeup Air to Isolation Condenser
Valve V-11-36 Accumulator
In order for OMA 18 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-36 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 OMA 18 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-36 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time. This scenario is unlikely for this particular area since
the plant would likely reach cold shutdown before the action is
required.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 18 is available
to provide makeup control air to the accumulator for V-11-36 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 18 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-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 3 and 18
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 stated that the fire loading in this zone is low and
that there is an administrative controls program in place to limit
additional combustible materials and sources of ignition. The licensee
also stated that 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 that 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
5650 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.
[[Page 19506]]
3.19.4 OMAs Credited for a Fire in This Zone
3.19.4.1 OMA 18--Provide Makeup Air to Isolation Condenser
Valve V-11-36 Accumulator
In order for OMA 18 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-36 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 OMA 18 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-36 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time. This scenario is unlikely for this particular area since
the plant would likely reach cold shutdown before the action is
required.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 18 is available
to provide makeup control air to the accumulator for V-11-36 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 18 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-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 OMA 18 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 stated that the fire loading in this zone is low and
that there is an administrative controls program in place to limit
additional combustible materials and sources of ignition. The licensee
also stated that 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 18--Provide Makeup Air to Isolation Condenser
Valve V-11-36 Accumulator
In order for OMA 18 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-36 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 OMA 18 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-36 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time. This scenario is unlikely for this particular area since
the plant would likely reach cold shutdown before the action is
required.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 18 is available
to provide makeup control air to the accumulator for V-11-36 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 18 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26
[[Page 19507]]
minutes, while the time available is 300 minutes, which provides a 244-
minute margin.
3.20.5 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 OMA 18 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 Yard
3.21.1 Fire Prevention
The licensee stated that no specific quantification of fire loading
was considered necessary for the Yard area since it is an outdoor area
with no ceiling or physical boundaries to contain heat and smoke from a
fire event.
3.21.2 Detection, Control, and Extinguishment
The licensee stated that there is no fire detection or fixed fire
suppression systems installed in this area but that manual suppression
is provided by a hose station from the office building and by fire
hydrants located throughout the Yard area.
3.21.3 Preservation of Safe Shutdown Capability
Since the Yard area 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.
3.21.4 OMAs Credited for a Fire in This Area
3.21.4.1 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.
3.21.4.2 OMA 17--Provide Makeup Air to Isolation Condenser
Valve V-11-34 Accumulator
In order for OMA 17 to be necessary, a loss of instrument
air to the isolation condenser valve V-11-34 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 OMA 17 connects a high
pressure air cylinder to the accumulator of Condensate Transfer System
valve V-11-34 and that these air-operated valves are used to control
makeup to the isolation condensers. Each valve is provided with an air
accumulator that provides a minimum of six full cycles. As a result,
this OMA is only necessary to ensure long-term operation of these
valves and makeup to the isolation condensers. Further, this OMA would
only be necessary if the plant had to remain in hot shutdown for an
extended time. This scenario is unlikely for this particular area since
the plant would likely reach cold shutdown before the action is
required.
In addition, the licensee stated that they maintain a fire support
procedure (ABN-35, ``Loss of Instrument Air'') that provides guidance
to perform this OMA if instrument air is lost and indicates that there
are four annunciator alarm windows that monitor instrument air
pressure, plus a pressure gauge on a panel in the control room for
instrument air pressure. If all of these instruments are not available,
then ABN-35 further indicates that the control rods will start to drift
into the core and the MSIVs will close, as well as multiple air-
operated valves changing state. Additionally, RPV level indication will
not be compromised by a fire in any zone or area. All of these
indications would help the operator diagnose the loss of instrument air
and initiate mitigating procedures.
In the unlikely event that a fire does occur and causes a loss of
instrument air to the air-operated valves, OMA 17 is available
to provide makeup control air to the accumulator for V-11-34 for the
isolation condenser makeup line due to the loss of instrument air. If
OMA 17 becomes necessary, the licensee stated that they have
assumed a 30-minute diagnosis period and that the required time to
perform the action is 26 minutes, while the time available is 300
minutes, which provides a 244-minute margin.
3.21.5 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 area, combined with the ability of OMAs 12
and 17 to manipulate the plant in the event of a fire that
damages safe shutdown equipment, provides adequate assurance that safe
shutdown capability is maintained.
3.22 Feasibility and Reliability of the Operator Manual Actions
This analysis postulates that OMAs may 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.
The following provides the Oyster Creek analysis of these criteria for
justifying the OMAs specified in this exemption.
3.22.1 Bases for Establishing Feasibility and Reliability
Using NUREG-1852, the NRC staff has evaluated the feasibility and
reliability 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
[[Page 19508]]
less than the time in which the OMA must be completed (time available).
3.22.2 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
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, or CO2) or a fire is confirmed.
In addition, the licensee stated that ABN-29 directs immediate entry
into the Fire Support Procedure (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
Emergency Operating Procedures 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 stated 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.
The licensee's analysis demonstrates that, for the expected
scenarios, the OMAs can be diagnosed and executed within the amount of
time available to complete them. The licensee's analysis also
demonstrates that various factors, as discussed above, have been
considered to address uncertainties in estimating the time available.
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'' verses ``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 is 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
----------------------------------------------------------------------------------------------------------------
OMA Required Available Margin
OMA Fire area/zone of fire origin location time (min) time (min) (min)
----------------------------------------------------------------------------------------------------------------
1........................... TB-FA-26, TB-FZ-11C, and TB-FZ- OB-FZ-8A 18 30 12
11D.
2........................... TB-FA-26, TB-FZ-11C, and TB-FZ- RB-FZ-1E 23 45 22
11D.
3........................... TB-FA-26, TB-FZ-11B, TB-FZ- OB-FZ-6B 38 180 142
11C, TB-FZ-11D, and TB-FZ-11E.
7........................... TB-FA-26, TB-FZ-11C, and TB-FZ- RB-FZ-1B 26 45 19
11D.
8........................... TB-FA-26, TB-FZ-11C, and TB-FZ- DG-FA-17 26 45 19
11D.
9........................... Yard.......................... RB-FZ-1E 45 204 159
17.......................... CW-FA-14, OB-FZ-6A, OB-FZ-8A, RB-FZ-1B 56 300 244
OB-FZ-8B, OB-FZ-8C, OB-FA-9,
RB-FZ-1D, RB-FZ-1E, RB-FZ-
1F3, RB-FZ-1F5, RB-FZ-1G, TB-
FA-3A, and Yard.
18.......................... OB-FZ-6B, TB-FA-26, TB-FZ-11B, RB-FZ-1B 56 300 244
TB-FZ-11C, TB-FZ-11D, TB-FZ-
11E, TB-FZ-11F, and TB-FZ-11H.
OB-FZ-10A..................... ........... 38 60 22
----------------------------------------------------------------------------------------------------------------
[[Page 19509]]
The NRC staff reviewed the required operator manual action
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 1 and requires an operator to trip the
field breakers for the recirculation pumps MG set so that the Fuel Zone
Level Indicators can be used. The action may be required as a result of
fire in TB-FA-26, TB-FZ-11C, or TB-FZ-11D. 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 operator
manual actions.
3.23 Reliability
The completion times noted in the table above provide reasonable
assurance that the OMAs can reliably be performed under a wide range of
conceivable conditions by different plant crews. This is because the
time margins associated with each action and other installed fire
protection features, account for sources of uncertainty such as
variations in fire and plant conditions, factors unable to be recreated
in demonstrations and human-centered factors. Therefore, the OMAs
included in this review are reliable because there is adequate time
available to account for uncertainties not only in estimates of the
time available, but also in estimates of how long it takes to diagnose
a fire and execute the OMAs. This is based, in part, on a plant
demonstration of the actions under non-fire conditions.
3.24 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.
3.25 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 fire protection program, in lieu of meeting the
requirements specified in 10 CFR Part 50, Appendix R, Section 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.
3.26 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.
3.27 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.
3.28 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 (75 FR 33656).
This exemption is effective upon issuance.
Dated at Rockville, Maryland, this 30th day of March 2011.
[[Page 19510]]
For the Nuclear Regulatory Commission.
Robert A. Nelson,
Acting Director, Division of Operating Reactor Licensing, Office of
Nuclear Reactor Regulation.
[FR Doc. 2011-8318 Filed 4-6-11; 8:45 am]
BILLING CODE 7590-01-P