ML15268A149
| ML15268A149 | |
| Person / Time | |
|---|---|
| Site: | Fermi  |
| Issue date: | 09/24/2015 |
| From: | Kaminskas V A DTE Electric Company, DTE Energy |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| GL-08-001, NRC-15-0090 | |
| Download: ML15268A149 (61) | |
Text
RHR Shutdown Cooling System-Hot Shutdown B 3.4.8 BASES LCO (continued)
common discharge piping. Thus, to meet the LCO, both pumps
in one loop or one pump in each of the two loops must be
OPERABLE. Since the piping and heat exchangers are passive
components that are assumed not to fail, they are allowed to
be common to both subsystems. Each shutdown cooling
subsystem is considered OPERABLE if it can be manually
aligned (remote or local) in the shutdown cooling mode for
removal of decay heat. In MODE 3, one RHR shutdown cooling
subsystem can provide the required cooling, but two
subsystems are required to be OPERABLE to provide
redundancy. Operation of one subsystem can maintain or
reduce the reactor coolant temperature as required.
However, to ensure adequate core flow to allow for accurate
average reactor coolant temperature monitoring, nearly
continuous operation is required.
Note 1 permits both RHR shutdown cooling subsystems to be
shut down for a period of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> in an 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> period. Note
2 allows one RHR shutdown cooling subsystem to be inoperable
for up to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for the performance of Surveillance tests.
These tests may be on the affected RHR System or on some
other plant system or component that necessitates placing
the RHR System in an inoperable status during the
performance. This is permitted because the core heat
generation can be low enough and the heatup rate slow enough
to allow some changes to the RHR subsystems or other
operations requiring RHR flow interruption and loss of
redundancy.
APPLICABILITY In MODE 3 with reactor steam dome pressure below the RHR
cut in permissive pressure (i.e., the actual pressure at
which the interlock resets) the RHR System may be operated
in the shutdown cooling mode to remove decay heat to reduce
or maintain coolant temperature. Otherwise, a recirculation
pump is required to be in operation.
In MODES 1 and 2, and in MODE 3 with reactor steam dome
pressure greater than or equal to the RHR cut in permissive
pressure, this LCO is not applicable. Operation of the RHR
System in the shutdown cooling mode is not allowed above
this pressure because the RCS pressure may exceed the design
pressure of the shutdown cooling piping. Decay heat removal
at reactor pressures greater than or equal to the RHR cut in
permissive pressure is typically accomplished by condensing FERMI - UNIT 2 B 3.4.8-2 Revision 0
RHR Shutdown Cooling System-Hot Shutdown B 3.4.8 BASES SURVEILLANCE REQUIREMENTS (continued)
Surveillance being met (i.e., forced coolant circulation is not required for this initial 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> period), which also
allows entry into the Applicability of this Specification in
accordance with SR 3.0.4 since the Surveillance will not be
"not met" at the time of entry into the Applicability. REFERENCES None.
FERMI - UNIT 2 B 3.4.8-6 Revision 0 Insert 1 SR 3.4.8.2 RHR Shutdown Cooling System piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RHR shutdown cooling subsystems and may also prevent water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel.
Selection of RHR Shutdown Cooling System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand
-by versus operating conditions.
The RHR Shutdown Cooling System is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations.
If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Shutdown Cooling System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.
RHR Shutdown Cooling System locations susceptible to gas accumulation are monitored and, if gas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are subject to the same gas intrusion mechanisms may be verified by monitoring a representative subset of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety. For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location. Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.
This SR is modified by a Note that states the SR is not required to be performed until 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after reactor steam dome pressure is < the RHR cut in permissive pressure. In a rapid shutdown, there may be insufficient time to verify all susceptible locations prior to entering the Applicability.
The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.
RHR Shutdown Cooling System -
Cold Shutdown B 3.4.9 BASES LCO (continued) in one loop or one pump in each of the two loops must be OPERABLE. Since the piping and heat exchangers are passive
components that are assumed not to fail, they are allowed to
be common to both subsystems. In MODE 4, the RHR cross tie
valve (E1150-F010) may be opened to allow pumps in one loop
to discharge through the opposite recirculation loop to make
a complete subsystem. Additionally, each shutdown cooling
subsystem is considered OPERABLE if it can be manually
aligned (remote or local) in the shutdown cooling mode for
removal of decay heat. In MODE 4, one RHR shutdown cooling
subsystem can provide the required cooling, but two
subsystems are required to be OPERABLE to provide
redundancy. Operation of one subsystem can maintain or
reduce the reactor coolant temperature as required.
However, to ensure adequate core flow to allow for accurate
average reactor coolant temperature monitoring, nearly
continuous operation is required.
Note 1 permits both RHR shutdown cooling subsystems to be
shut down for a period of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> in an 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> period.
Note 2 allows one RHR shutdown cooling subsystem to be
inoperable for up to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for the performance of
Surveillance tests. These tests may be on the affected RHR
System or on some other plant system or component that
necessitates placing the RHR System in an inoperable status
during the performance. This is permitted because the core
heat generation can be low enough and the heatup rate slow
enough to allow some changes to the RHR subsystems or other
operations requiring RHR flow interruption and loss of
redundancy. APPLICABILITY In MODE 4, the RHR Shutdown Cooling System may be operated in the shutdown cooling mode to remove decay heat to
maintain coolant temperature below 200F. Otherwise, a recirculation pump is required to be in operation. However,
when decay losses to ambient are sufficient to maintain
reactor coolant temperature steady at the existing
temperature the requirements for the RHR Shutdown Cooling
System are not necessary to assure continued safe operation.
In MODES 1 and 2, and in MODE 3 with reactor steam dome
pressure greater than or equal to the RHR cut in permissive
pressure, this LCO is not applicable. Operation of the RHR
System in the shutdown cooling mode is not allowed above FERMI - UNIT 2 B 3.4.9-2 Revision 0 RHR Shutdown Cooling System -
Cold Shutdown B 3.4.9 BASES SURVEILLANCE SR 3.4.9.1 REQUIREMENTS This Surveillance verifies that one RHR shutdown cooling subsystem or recirculation pump is in operation and
circulating reactor coolant. The required flow rate is
determined by the flow rate necessary to provide sufficient
decay heat removal capability. The Surveillance Frequency
is controlled under the Surveillance Frequency Control
Program.
REFERENCES None. FERMI - UNIT 2 B 3.4.9-5 Revision 64 Insert 2 SR 3.4.9.2 RHR Shutdown Cooling System piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RHR shutdown cooling subsystems and may also prevent water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel.
Selection of RHR Shutdown Cooling System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand
-by versus operating conditions.
The RHR Shutdown Cooling System is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations.
If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Shutdown Cooling System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.
RHR Shutdown Cooling System locations susceptible to gas accumulation are monitored and, if gas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are subject to the same gas intrusion mechanisms may be verified by monitoring a representative subset of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety. For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location. Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.
The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.
ECCS-Operating B 3.5.1 BASES APPLICABLE SAFETY ANALYSES (continued) b.Maximum cladding oxidation is 0.17 times the total cladding thickness before oxidation;c.Maximum hydrogen generation from a zirconium water reaction is 0.01 times the hypothetical amount that would be generated if all of the metal in the cladding surrounding the fuel, excluding the cladding
surrounding the plenum volume, were to react;d.The core is maintained in a coolable geometry; ande.Adequate long term cooling capability is maintained.
The limiting single failures are discussed in Reference 11.
The Design Basis Accident recirculation suction line break
with the failure of the Division II battery results in the
highest nominal peak cladding temperature. One ADS valve
failure is analyzed as a limiting single failure for events
requiring ADS operation. The remaining OPERABLE ECCS
subsystems provide the capability to adequately cool the
core and prevent excessive fuel damage.
The ECCS satisfy Criterion 3 of 10 CFR 50.36(c)(2)(ii).
LCO Each ECCS injection/spray subsystem and five ADS valves are
required to be OPERABLE. The ECCS injection/spray
subsystems are defined as the two CS subsystems, the two
LPCI subsystems, and one HPCI System. The low pressure ECCS
injection/spray subsystems are defined as the two CS
subsystems and the two LPCI subsystems.
With less than the required number of ECCS subsystems
OPERABLE, the potential exists that during a limiting design
basis LOCA concurrent with the worst case single failure,
the limits specified in Reference 10 could be exceeded. All
ECCS subsystems must therefore be OPERABLE to satisfy the
single failure criterion required by Reference 10.
LPCI subsystems may be considered OPERABLE during alignment
and operation for decay heat removal when below the actual
RHR cut in permissive pressure in MODE 3, if capable of
being manually realigned (remote or local) to the LPCI mode
and not otherwise inoperable. At these low pressures and
decay heat levels, a reduced complement of ECCS subsystems
should provide the required core cooling, thereby allowing
operation of RHR shutdown cooling when necessary.
FERMI - UNIT 2 B 3.5.1-5 Revision 55 ECCS-Operating B 3.5.1 BASES SURVEILLANCE REQUIREMENTS (continued)
This SR is modified by a Note to indicate that when this test results in LPCI inoperability solely for performance of
this required Surveillance, or when the LPCI swing bus
automatic throwover scheme is inoperable due to EDG-12 being
paralleled to the bus for required testing, entry into
associated Conditions and Required Actions may be delayed
for up to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> until the required testing is completed.
Upon completion of the Surveillance or expiration of the
12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> allowance the swing bus must be returned to OPERABLE
status or the applicable Condition entered and Required
Actions taken. The LPCI swing bus automatic throwover scheme
is typically not inoperable when EDG-12 is paralleled to the
bus for testing purposes.
SR 3.5.1.3 The flow path piping has the potential to develop voids and
pockets of entrained air. Maintaining the pump discharge
lines of the HPCI System, CS System, and LPCI subsystems
full of water ensures that the ECCS will perform properly,
injecting its full capacity into the RCS upon demand. This
will also prevent a water hammer following an ECCS
initiation signal. One acceptable method of ensuring that
the lines are full is to vent at the high points. The
Surveillance Frequency is controlled under the Surveillance
Frequency Control Program.
SR 3.5.1.4 Verifying the correct alignment for manual, power operated,
and automatic valves in the ECCS flow paths provides
assurance that the proper flow paths will exist for ECCS
operation. This SR does not apply to valves that are
locked, sealed, or otherwise secured in position since these
were verified to be in the correct position prior to
locking, sealing, or securing. A valve that receives an
initiation signal is allowed to be in a non-accident
position provided the valve will automatically reposition in
the proper stroke time. This SR does not require any
testing or valve manipulation; rather, it involves FERMI - UNIT 2 B 3.5.1-13 Revision 64 Insert 3 The ECCS injection/spray subsystem flow path piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the ECCS injection/spray subsystems and may also prevent a water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel.
Selection of ECCS injection/spray subsystem locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand
-by versus operating conditions.
The ECCS injection/spray subsystem is OPERABLE when it is sufficiently filled with water.
Acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the ECCS injection/spray subsystems are not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.
ECCS injection/spray subsystem locations susceptible to gas accumulation are monitored and, if gas is found, the gas volume is compared to the acceptance criteria for the location.
Susceptible locations in the same system flow path which are subject to the same gas intrusion mechanisms may be verified by monitoring a representative subset of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety. For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location. Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.
ECCS-Operating B 3.5.1 BASES SURVEILLANCE REQUIREMENTS (continued) verification that those valves capable of potentially being mispositioned are in the correct position. This SR does not
apply to valves that cannot be inadvertently misaligned,
such as check valves. For the HPCI System, this SR also
includes the steam flow path for the turbine and the flow
controller position.
The Surveillance Frequency is controlled under the
Surveillance Frequency Control Program.
This SR is modified by a Note that allows LPCI subsystems to
be considered OPERABLE during alignment and operation for
decay heat removal with reactor steam dome pressure less
than the RHR cut in permissive pressure in MODE 3, and for 4
hours after exceeding the RHR cut-in permissive pressure in
MODE 3, if capable of being manually realigned (remote or
local) to the LPCI mode and not otherwise inoperable. This
allows operation in the RHR shutdown cooling mode during
MODE 3, if necessary and sufficient time to restore the
system line up to the LPCI mode of operation.
SR 3.5.1.5 Verification that ADS primary containment pneumatic supply
pressure is 75 psig ensures adequate air or nitrogen pressure for reliable ADS operation. The accumulator on
each ADS valve provides pneumatic pressure for valve
actuation. The design pneumatic supply pressure
requirements for the accumulator are such that, following a
failure of the pneumatic supply to the accumulator, at least
five valve actuations can occur with the drywell at the long
term drywell pressure of the design basis small break LOCA
analysis (Ref. 15). The ECCS safety analysis assumes only
one actuation to achieve the depressurization required for
operation of the low pressure ECCS. This minimum required
pressure of 75 psig is provided by the primary pneumatic supply system. The Surveillance Frequency is controlled
under the Surveillance Frequency Control Program.
FERMI - UNIT 2 B 3.5.1-14 Revision 64 ECCS-Shutdown B 3.5.2 B 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS) AND REACTOR CORE ISOLATION COOLING (RCIC) SYSTEM B 3.5.2 ECCS-Shutdown BASES BACKGROUND A description of the Core Spray (CS) System and the low pressure coolant injection (LPCI) mode of the Residual Heat
Removal (RHR) System is provided in the Bases for LCO 3.5.1, "ECCS-Operating."
APPLICABLE The ECCS performance is evaluated for the entire spectrum of SAFETY ANALYSES break sizes for a postulated loss of coolant accident (LOCA). The long term cooling analysis following a design
basis LOCA (Ref. 1) demonstrates that only one low pressure
ECCS injection/spray subsystem is required, post LOCA, to
maintain adequate reactor vessel water level in the event of
an inadvertent vessel draindown. It is reasonable to
assume, based on engineering judgement, that while in MODES
4 and 5, one low pressure ECCS injection/spray subsystem can
maintain adequate reactor vessel water level. To provide
redundancy, a minimum of two low pressure ECCS
injection/spray subsystems are required to be OPERABLE in
MODES 4 and 5.
The low pressure ECCS subsystems satisfy Criterion 3 of
LCO Two low pressure ECCS injection/spray subsystems are
required to be OPERABLE. The low pressure ECCS injection/
spray subsystems consist of two CS subsystems and two LPCI
subsystems. Each CS subsystem consists of two motor driven
pumps, piping, and valves to transfer water from the
suppression pool or condensate storage tank (CST) to the
reactor pressure vessel (RPV). Each LPCI subsystem consists
of two motor driven pumps, piping, and valves to transfer
water from the suppression pool to the RPV. In MODES 4
and 5, the RHR System cross tie valves are not required to
be open provided action is taken to assure that OPERABLE
LPCI subsystems are capable of injection to the reactor
vessel. FERMI - UNIT 2 B 3.5.2-1 Revision 0 ECCS-Shutdown B 3.5.2 BASES SURVEILLANCE REQUIREMENTS (continued)
SR 3.5.2.5 Verifying the correct alignment for manual, power operated, and automatic valves in the ECCS flow paths provides
assurance that the proper flow paths will exist for ECCS
operation. This SR does not apply to valves that are
locked, sealed, or otherwise secured in position, since
these valves were verified to be in the correct position
prior to locking, sealing, or securing. A valve that
receives an initiation signal is allowed to be in a
nonaccident position provided the valve will automatically
reposition in the proper stroke time. This SR does not
require any testing or valve manipulation; rather, it
involves verification that those valves capable of
potentially being mispositioned are in the correct position.
This SR does not apply to valves that cannot be
inadvertently misaligned, such as check valves. The
Surveillance Frequency is controlled under the Surveillance
Frequency Control Program.
In MODES 4 and 5, the RHR System may operate in the shutdown
cooling mode to remove decay heat and sensible heat from the
reactor. Therefore, RHR valves that are required for LPCI
subsystem operation may be aligned for decay heat removal.
Therefore, this SR is modified by a Note that allows one or
both LPCI subsystems of the RHR System to be considered
OPERABLE for the ECCS function if all the required valves in
the LPCI flow path can be manually realigned (remote or
local) to allow injection into the RPV, and the system is
not otherwise inoperable. This will ensure adequate core
cooling if an inadvertent RPV draindown should occur. REFERENCES 1.
UFSAR, Section 6.3.2.
FERMI - UNIT 2 B 3.5.2-6 Revision 64 RCIC System B 3.5.3 BASES BACKGROUND (continued)
The RCIC pump is provided with a minimum flow bypass line, which discharges to the suppression pool. The valve in this
line automatically opens to prevent pump damage due to
overheating when other discharge line valves are closed. To
ensure rapid delivery of water to the RPV and to minimize
water hammer effects, the RCIC System discharge piping is
kept full of water. The RCIC System is normally aligned to
the CST. The height of water in the CST is sufficient to
maintain the piping full of water up to the first isolation
valve. The relative height of the feedwater line connection
for RCIC is such that the water in the feedwater lines keeps
the remaining portion of the RCIC discharge line full of
water. Therefore, RCIC does not require a "keep fill"
system. APPLICABLE The function of the RCIC System is to respond to transient SAFETY ANALYSES events by providing makeup coolant to the reactor. The RCIC System is not an Engineered Safety Feature System and no
credit is taken in the safety analyses for RCIC System
operation. Based on its contribution to the reduction of
overall plant risk, however, the system is included in the
Technical Specifications, as required by 10 CFR
50.36(c)(2)(ii).
LCO The OPERABILITY of the RCIC System provides adequate core
cooling such that actuation of any of the low pressure ECCS
subsystems is not required in the event of RPV isolation
accompanied by a loss of feedwater flow. The RCIC System
has sufficient capacity for maintaining RPV inventory during
an isolation event. APPLICABILITY The RCIC System is required to be OPERABLE during MODE 1, and MODES 2 and 3 with reactor steam dome pressure
> 150 psig, since RCIC is the primary non-ECCS water source
for core cooling when the reactor is isolated and
pressurized. In MODES 2 and 3 with reactor steam dome
pressure 150 psig, and in MODES 4 and 5, RCIC is not required to be OPERABLE since the low pressure ECCS
injection/spray subsystems can provide sufficient flow to
the RPV.
FERMI - UNIT 2 B 3.5.3-2 Revision 0 RCIC System B 3.5.3 BASES SURVEILLANCE SR 3.5.3.1 REQUIREMENTS The flow path piping has the potential to develop voids and pockets of entrained air. Maintaining the pump discharge
line of the RCIC System full of water ensures that the
system will perform properly, injecting its full capacity
into the Reactor Coolant System upon demand. This will also
prevent a water hammer following an initiation signal. One
acceptable method of ensuring the line is full is to vent at
the high points. The Surveillance Frequency is controlled
under the Surveillance Frequency Control Program.
SR 3.5.3.2 Verifying the correct alignment for manual, power operated,
and automatic valves in the RCIC flow path provides
assurance that the proper flow path will exist for RCIC
operation. This SR does not apply to valves that are
locked, sealed, or otherwise secured in position since these
valves were verified to be in the correct position prior to
locking, sealing, or securing. A valve that receives an
initiation signal is allowed to be in a nonaccident position
provided the valve will automatically reposition in the
proper stroke time. This SR does not require any testing or
valve manipulation; rather, it involves verification that
those valves capable of potentially being mispositioned are
in the correct position. This SR does not apply to valves
that cannot be inadvertently misaligned, such as check
valves. For the RCIC System, this SR also includes the
steam flow path for the turbine and the flow controller
position.
The Surveillance Frequency is controlled under the
Surveillance Frequency Control Program.
FERMI - UNIT 2 B 3.5.3-5 Revision 64 Insert 4 The RCIC System flow path piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RCIC System and may also prevent a water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel.
Selection of RCIC System locations susceptible to gas accumulation is based on a self
-assessment of the piping configuration to identify where gases may accumulate and remain even after the system is filled and vented, and to identify vulnerable potential degassing flow paths. The review is supplemented by verification that installed high
-point vents are actually at the system high points, including field verification to ensure pipe shapes and construction tolerances have not inadvertently created additional high points. Susceptible locations depend on plant and system configuration, such as stand
-by versus operating conditions.
The RCIC System is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RCIC Systems are not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met.
Accumulated gas should be eliminated or brought within the acceptance criteria limits.
RCIC System locations susceptible to gas accumulation are monitored and, if gas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are subject to the same gas intrusion mechanisms may be verified by monitoring a representative sub
-set of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety. For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location. Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.
RHR Suppression Pool Cooling B 3.6.2.3 BASES APPLICABLE Reference 1 contains the results of analyses used to predict SAFETY ANALYSES primary containment pressure and temperature following large and small break LOCAs. The intent of the analyses is to
demonstrate that the heat removal capacity of the RHR
Suppression Pool Cooling System is adequate to maintain the
primary containment conditions within design limits. The
suppression pool temperature is calculated to remain below
the design limit.
The RHR Suppression Pool Cooling System satisfies
Criterion 3 of 10 CFR 50.36(c)(2)(ii).
LCO During a DBA, a minimum of one RHR suppression pool cooling
subsystem is required to maintain the primary containment
peak pressure and temperature below design limits (Ref. 1).
To ensure that these requirements are met, two RHR
suppression pool cooling subsystems must be OPERABLE with
power from two safety related independent power supplies.
Therefore, in the event of an accident, at least one
subsystem is OPERABLE assuming the worst case single active
failure. An RHR suppression pool cooling subsystem is
OPERABLE when one of the pumps, the heat exchanger, and
associated piping, valves, instrumentation, and controls are
OPERABLE. APPLICABILITY In MODES 1, 2, and 3, a DBA could cause a release of radioactive material to primary containment and cause a
heatup and pressurization of primary containment. In
MODES 4 and 5, the probability and consequences of these
events are reduced due to the pressure and temperature
limitations in these MODES. Therefore, the RHR Suppression
Pool Cooling System is not required to be OPERABLE in MODE 4
or 5. ACTIONS A.1 With one RHR suppression pool cooling subsystem inoperable,
the inoperable subsystem must be restored to OPERABLE status
within 7 days. In this Condition, the remaining RHR
suppression pool cooling subsystem is adequate to perform
the primary containment cooling function. However, the FERMI - UNIT 2 B 3.6.2.3-2 Revision 59 RHR Suppression Pool Cooling B 3.6.2.3 BASES SURVEILLANCE REQUIREMENTS (continued) manually initiated. This SR does not require any testing or valve manipulation; rather, it involves verification that
those valves capable of being mispositioned are in the
correct position. This SR does not apply to valves that
cannot be inadvertently misaligned, such as check valves.
The Surveillance Frequency is controlled under the
Surveillance Frequency Control Program.
SR 3.6.2.3.2 Verifying that each required RHR pump develops a flow rate 9,250 gpm while operating in the suppression pool cooling mode with flow through the associated heat exchanger ensures
that pump performance has not degraded during the cycle.
Flow is a normal test of centrifugal pump performance
required by ASME Code,Section XI (Ref. 3). This test
confirms one point on the pump design curve, and the results
are indicative of overall performance. Such inservice
inspections confirm component OPERABILITY, trend
performance, and detect incipient failures by indicating
abnormal performance. The Frequency of this SR is in
accordance with the Inservice Testing Program. REFERENCES 1.UFSAR, Section 6.2.2.NEDC-32988-A, Revision 2, Technical Justification to Support Risk- Informed Modification to Selected
Required End States for BWR Plants, December 2002.
3.ASME, Boiler and Pressure Vessel Code,Section XI.FERMI - UNIT 2 B 3.6.2.3-5 Revision 64 Insert 5 SR 3.6.2.3.3 RHR Suppression Pool Cooling System piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RHR suppression pool cooling subsystems and may also prevent water hammer and pump cavitation.
Selection of RHR Suppression Pool Cooling System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand
-by versus operating conditions.
The RHR Suppression Pool Cooling System is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Suppression Pool Cooling System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.
RHR Suppression Pool Cooling System locations susceptible to gas accumulation are monitored and, if gas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path w hich are subject to the same gas intrusion mechanisms may be verified by monitoring a representative subset of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety. For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location. Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.
The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.
RHR Suppression Pool Spray B 3.6.2.4
BASES APPLICABLE Reference 1 contains the results of analyses used to predict SAFETY ANALYSES primary containment pressure and temperature following large and small break loss of coolant accidents. The intent of
the analyses is to demonstrate that the pressure reduction
capacity of the RHR Suppression Pool Spray System is
adequate to maintain the primary containment conditions
within design limits. The time history for primary
containment pressure is calculated to demonstrate that the
maximum pressure remains below the design limit.
The RHR Suppression Pool Spray System satisfies Criterion 3
LCO In the event of a DBA, a minimum of one RHR suppression pool
spray subsystem is required to mitigate potential bypass
leakage paths and maintain the primary containment peak
pressure below the design limits (Ref. 1). To ensure that
these requirements are met, two RHR suppression pool spray
subsystems must be OPERABLE with power from two safety
related independent power supplies. Therefore, in the event
of an accident, at least one subsystem is OPERABLE assuming
the worst case single active failure. An RHR suppression
pool spray subsystem is OPERABLE when one of the RHR pumps,
the heat exchanger, and associated piping, valves,
instrumentation, and controls are OPERABLE.
APPLICABILITY In MODES 1, 2, and 3, a DBA could cause pressurization of primary containment. In MODES 4 and 5, the probability and
consequences of these events are reduced due to the pressure
and temperature limitations in these MODES. Therefore,
maintaining RHR suppression pool spray subsystems OPERABLE
is not required in MODE 4 or 5.
ACTIONS A.1
With one RHR suppression pool spray subsystem inoperable,
the inoperable subsystem must be restored to OPERABLE status
within 7 days. In this Condition, the remaining OPERABLE
RHR suppression pool spray subsystem is adequate to perform
the primary containment bypass leakage mitigation function.
However, the overall reliability is reduced because a single FERMI - UNIT 2 B 3.6.2.4-2 Revision 0 RHR Suppression Pool Spray B 3.6.2.4 BASES ACTIONS (continued)
that are required to comply with ACTIONS or that are part of
a shutdown of the unit.
The allowed Completion Time is reasonable, based on
operating experience, to reach the required plant conditions
from full power conditions in an orderly manner and without
challenging plant systems.
SURVEILLANCE SR 3.6.2.4.1 REQUIREMENTS
Verifying the correct alignment for manual, power operated,
and automatic valves in the RHR suppression pool spray mode
flow path provides assurance that the proper flow paths will
exist for system operation. This SR does not apply to
valves that are locked, sealed, or otherwise secured in
position since these valves were verified to be in the
correct position prior to locking, sealing, or securing. A
valve is also allowed to be in the nonaccident position
provided it can be aligned to the accident position within
the time assumed in the accident analysis. This is
acceptable since the RHR suppression pool cooling mode is
manually initiated. This SR does not require any testing or valve manipulation; rather, it involves verification that
those valves capable of being mispositioned are in the
correct position. This SR does not apply to valves that
cannot be inadvertently misaligned, such as check valves.
The Surveillance Frequency is controlled under the
Surveillance Frequency Control Program.
SR 3.6.2.4.2 Verifying each RHR pump develops a flow rate 500 gpm while operating in the suppression pool spray mode with flow
through the heat exchanger ensures that pump performance has
not degraded during the cycle. Flow is a normal test of
centrifugal pump performance required by Section XI of the
ASME Code (Ref. 3). This test confirms one point on the
pump design curve and is indicative of overall performance.
Such inservice inspections confirm component OPERABILITY, FERMI - UNIT 2 B 3.6.2.4-4 Revision 64 Insert 6 SR 3.6.2.4.3 RHR Suppression Pool Spray System piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RHR suppression pool spray subsystems and may also prevent water hammer and pump cavitation.
Selection of RHR Suppression Pool Spray System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand
-by versus operating conditions.
The RHR Suppression Pool Spray System is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Suppression Pool Spray System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.
RHR Suppression Pool Spray System locations susceptible to gas accumulation are monitored and, if gas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are subject to the same gas intrusion mechanisms may be verified by monitoring a representative subset of susceptible locations.
Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety. For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location. Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.
The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.
RHR-High Water Level B 3.9.7 BASES LCO (continued) line may be used to allow pumps in one loop to discharge into the opposite loop's recirculation line to make a
complete subsystem.
Additionally, each RHR shutdown cooling subsystem is
considered OPERABLE if it can be manually aligned (remote or
local) in the shutdown cooling mode for removal of decay
heat. Operation (either continuous or intermittent) of one
subsystem can maintain and reduce the reactor coolant
temperature as required. APPLICABILITY One RHR shutdown cooling subsystem must be OPERABLE in MODE 5, with irradiated fuel in the reactor pressure vessel,
with the water level 20 ft 6 inches above the top of the RPV flange, and heat losses to ambient not greater than or
equal to heat input to the reactor coolant to provide decay
heat removal. RHR System requirements in other MODES are
covered by LCOs in Section 3.4, Reactor Coolant System
(RCS); Section 3.5, Emergency Core Cooling Systems (ECCS)
and Reactor Core Isolation Cooling (RCIC) System; and
Section 3.6, Containment Systems. RHR Shutdown Cooling
System requirements in MODE 5 with irradiated fuel in the
reactor pressure vessel and with the water level < 20 ft
6 inches above the RPV flange are given in LCO 3.9.8. ACTIONS A.1 With no RHR shutdown cooling subsystem OPERABLE, the
availability of an alternate method of decay heat removal
must be established within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. In this condition, the
volume of water above the RPV flange provides adequate
capability to remove decay heat from the reactor core.
However, the overall reliability is reduced because loss of
water level could result in reduced decay heat removal
capability. The 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> Completion Time is based on decay
heat removal function and the probability of a loss of the
available decay heat removal capabilities. Furthermore, FERMI - UNIT 2 B 3.9.7-2 Revision 0 RHR-High Water Level B 3.9.7 BASES SURVEILLANCE SR 3.9.7.1 REQUIREMENTS This Surveillance demonstrates that the RHR shutdown cooling subsystem is capable of decay heat removal.
The verification includes assuring that the shutdown cooling
subsystem is capable of taking suction from the reactor
vessel and discharging back to the reactor vessel through an
RHR heat exchanger with available cooling water. This SR
does not require any testing or valve manipulation, rather,
it involves verification that those valves not locked,
sealed, or otherwise secured in the correct position, can be
aligned to the correct position for shutdown cooling
operation. The Surveillance Frequency is controlled under
the Surveillance Frequency Control Program. REFERENCES None FERMI - UNIT 2 B 3.9.7-4 Revision 64 Insert 7 SR 3.9.7.2 RHR Shutdown Cooling System piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the required RHR shutdown cooling subsystem(s) and may also prevent water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel.
Selection of RHR Shutdown Cooling System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand
-by versus operating conditions.
The RHR Shutdown Cooling System is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations.
If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Shutdown Cooling System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.
RHR Shutdown Cooling System locations susceptible to gas accumulation are monitored and, if gas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are subject to the same gas intrusion mechanisms may be verified by monitoring a representative subset of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety. For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location. Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.
The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.
The Surveillance Frequency may vary by location susceptible to gas accumulation.
RHR-Low Water Level B 3.9.8 BASES LCO (continued) opposite loop's recirculation line to make a complete subsystem.
Additionally, each RHR shutdown cooling subsystem is
considered OPERABLE if it can be manually aligned (remote or
local) in the shutdown cooling mode for removal of decay
heat. Operation (either continuous or intermittent) of one
subsystem can maintain and reduce the reactor coolant
temperature as required. However, to ensure adequate core
flow to allow for accurate average reactor coolant
temperature monitoring, nearly continuous operation of
either an RHR pump or a recirculation pump is required.
Note 1 is provided to allow a 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> exception to shut down
the operating subsystem every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.
Note 2 is provided to allow a 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> exception for a single
subsystem inoperability due to surveillance testing. APPLICABILITY Two RHR shutdown cooling subsystems are required to be OPERABLE, and one RHR pump or recirculation pump must be in
operation in MODE 5, with irradiated fuel in the RPV, with
the water level < 20 ft 6 inches above the top of the RPV
flange, and heat losses to ambient not greater than or equal
to heat input to the reactor coolant to provide decay heat
removal. RHR System requirements in other MODES are covered
by LCOs in Section 3.4, Reactor Coolant System (RCS);
Section 3.5, Emergency Core Cooling Systems (ECCS) and
Reactor Core Isolation Cooling (RCIC) System; and
Section 3.6, Containment Systems. RHR Shutdown Cooling
System requirements in MODE 5 with irradiated fuel in the
RPV and with the water level 20 ft 6 inches above the RPV flange are given in LCO 3.9.7, "Residual Heat Removal (RHR-High Water Level."
FERMI - UNIT 2 B 3.9.8-2 Revision 0 RHR-Low Water Level B 3.9.8 BASES SURVEILLANCE REQUIREMENTS (continued)
SR 3.9.8.2 This Surveillance demonstrates that the RHR shutdown cooling subsystem is capable of decay heat removal. The
verification includes assuring that the shutdown cooling
subsystem is capable of taking suction from the reactor
vessel and discharging back to the reactor vessel through an
RHR heat exchanger with available cooling water. This SR
does not require any testing or valve manipulation, rather,
it involves verification that those valves capable of being
mispositioned are in the correct position.
The Surveillance Frequency is controlled under the
Surveillance Frequency Control Program. REFERENCES None FERMI - UNIT 2 B 3.9.8-5 Revision 64 Insert 8 SR 3.9.8.3 RHR Shutdown Cooling System piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RHR shutdown cooling subsystems and may also prevent water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel.
Selection of RHR Shutdown Cooling System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand
-by versus operating conditions.
The RHR Shutdown Cooling System is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations.
If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Shutdown Cooling System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.
RHR Shutdown Cooling System locations susceptible to gas accumulation are monitored and, if gas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are subject to the same gas intrusion mechanisms may be verified by monitoring a representative sub
- set of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety. For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location. Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval. The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.