RS-11-159, Quad Cities, Units 1 and 2 - Technical Specification Bases
ML11305A135 | |
Person / Time | |
---|---|
Site: | Quad Cities |
Issue date: | 10/19/2011 |
From: | Exelon Generation Co, Exelon Nuclear |
To: | Office of Nuclear Reactor Regulation |
References | |
RS-11-159 | |
Download: ML11305A135 (725) | |
Text
Quad Cities Nuclear Power Station Technical Specifications Bases (TS Bases)
October 2011
Quad Cities Nuclear Power Station, Unit 1 and 2 Renewed Facility Operating License Nos. DPR-29 (Unit 1) and DPR-30 (Unit 2) NRC Docket Nos. STN 50-254 (Unit 1) and 50-265 (Unit 2)
Quad Cities 1 and 2 i Revision 41
TABLE OF CONTENTS
B 2.0 SAFETY LIMITS (SLs)
B 2.1.1 Reactor Core SLs....................................B 2.1.1-1 B 2.1.2 Reactor Coolant System (RCS) Pressure SL ...........B 2.1.2-1
B 3.0 LIMITING CONDITION FOR OPERATION (LCO) APPLICABILITY...B 3.0-1 B 3.0 SURVEILLANCE REQUIREMENT (SR) APPLICABILITY............B 3.0-13
B 3.1 REACTIVITY CONTROL SYSTEMS B 3.1.1 SHUTDOWN MARGIN (SDM)...............................B 3.1.1-1 B 3.1.2 Reactivity Anomalies................................B 3.1.2-1 B 3.1.3 Control Rod OPERABILITY.............................B 3.1.3-1 B 3.1.4 Control Rod Scram Times.............................B 3.1.4-1 B 3.1.5 Control Rod Scram Accumulators......................B 3.1.5-1 B 3.1.6 Rod Pattern Control.................................B 3.1.6-1 B 3.1.7 Standby Liquid Control (SLC) System.................B 3.1.7-1 B 3.1.8 Scram Discharge Volume (SDV) Vent and Drain Valves..B 3.1.8-1
B 3.2 POWER DISTRIBUTION LIMITS B 3.2.1 AVERAGE PLANAR LINEAR HEAT GENERATION RATE (APLHGR)..........................................B 3.2.1-1 B 3.2.2 MINIMUM CRITICAL POWER RATIO (MCPR).................B 3.2.2-1 B 3.2.3 LINEAR HEAT GENERATION RATE (LHGR) .................B 3.2.3-1 B 3.3 INSTRUMENTATION B 3.3.1.1 Reactor Protection System (RPS) Instrumentation.....B 3.3.1.1-1 B 3.3.1.2 Source Range Monitor (SRM) Instrumentation..........B 3.3.1.2-1 B 3.3.1.3 Oscillation Power Range Monitor (OPRM)
Instrumentation...................................B 3.3.1.3-1 B 3.3.2.1 Control Rod Block Instrumentation...................B 3.3.2.1-1 B 3.3.2.2 Feedwater System and Main Turbine High Water Level Trip Instrumentation..............................B 3.3.2.2-1 B 3.3.3.1 Post Accident Monitoring (PAM) Instrumentation......B 3.3.3.1-1 B 3.3.4.1 Anticipated Transient Without Scram Recirculation Pump Trip (ATWS-RPT) Instrumentation..............B 3.3.4.1-1 B 3.3.5.1 Emergency Core Cooling System (ECCS) Instrumentation...................................B 3.3.5.1-1 B 3.3.5.2 Reactor Core Isolation Cooling (RCIC) System Instrumentation...................................B 3.3.5.2-1 B 3.3.6.1 Primary Containment Isolation Instrumentation.......B 3.3.6.1-1 B 3.3.6.2 Secondary Containment Isolation Instrumentation.....B 3.3.6.2-1 B 3.3.6.3 Relief Valve Instrumentation........................B 3.3.6.3-1 B 3.3.7.1 Control Room Emergency Ventilation (CREV) System Instrumentation............................B 3.3.7.1-1 B 3.3.7.2 Mechanical Vacuum Pump Trip Instrumentation.........B 3.3.7.2-1 B 3.3.8.1 Loss of Power (LOP) Instrumentation.................B 3.3.8.1-1 B 3.3.8.2 Reactor Protection System (RPS) Electric Power Monitoring........................................B 3.3.8.2-1 (continued)
Quad Cities 1 and 2 ii Revision 0
TABLE OF CONTENTS (continued)
B 3.4 REACTOR COOLANT SYSTEM (RCS)
B 3.4.1 Recirculation Loops Operating.......................B 3.4.1-1 B 3.4.2 Jet Pumps...........................................B 3.4.2-1 B 3.4.3 Safety and Relief Valves ...........................B 3.4.3-1 B 3.4.4 RCS Operational LEAKAGE.............................B 3.4.4-1 B 3.4.5 RCS Leakage Detection Instrumentation...............B 3.4.5-1 B 3.4.6 RCS Specific Activity...............................B 3.4.6-1 B 3.4.7 Residual Heat Removal (RHR) Shutdown Cooling System-Hot Shutdown...............................B 3.4.7-1 B 3.4.8 Residual Heat Removal (RHR) Shutdown Cooling System-Cold Shutdown..............................B 3.4.8-1 B 3.4.9 RCS Pressure and Temperature (P/T) Limits...........B 3.4.9-1 B 3.4.10 Reactor Steam Dome Pressure.........................B 3.4.10-1
B 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS) AND REACTOR CORE ISOLATION COOLING (RCIC) SYSTEM B 3.5.1 ECCS-Operating......................................B 3.5.1-1 B 3.5.2 ECCS-Shutdown.......................................B 3.5.2-1 B 3.5.3 RCIC System.........................................B 3.5.3-1
B 3.6 CONTAINMENT SYSTEMS B 3.6.1.1 Primary Containment.................................B 3.6.1.1-1 B 3.6.1.2 Primary Containment Air Lock........................B 3.6.1.2-1 B 3.6.1.3 Primary Containment Isolation Valves (PCIVs)........B 3.6.1.3-1 B 3.6.1.4 Drywell Pressure....................................B 3.6.1.4-1 B 3.6.1.5 Drywell Air Temperature.............................B 3.6.1.5-1 B 3.6.1.6 Low Set Relief Valves...............................B 3.6.1.6-1 B 3.6.1.7 Reactor Building-to-Suppression Chamber Vacuum Breakers..........................................B 3.6.1.7-1 B 3.6.1.8 Suppression Chamber-to-Drywell Vacuum Breakers......B 3.6.1.8-1 B 3.6.2.1 Suppression Pool Average Temperature................B 3.6.2.1-1 B 3.6.2.2 Suppression Pool Water Level........................B 3.6.2.2-1 B 3.6.2.3 Residual Heat Removal (RHR) Suppression Pool Cooling......................................B 3.6.2.3-1 B 3.6.2.4 Residual Heat Removal (RHR) Suppression Pool Spray..B 3.6.2.4-1 B 3.6.2.5 Drywell-to-Suppression Chamber Differential Pressure..........................................B 3.6.2.5-1 B 3.6.3.1 Primary Containment Oxygen Concentration............B 3.6.3.1-1 B 3.6.4.1 Secondary Containment...............................B 3.6.4.1-1 B 3.6.4.2 Secondary Containment Isolation Valves (SCIVs)......B 3.6.4.2-1 B 3.6.4.3 Standby Gas Treatment (SGT) System..................B 3.6.4.3-1
B 3.7 PLANT SYSTEMS B 3.7.1 Residual Heat Removal Service Water (RHRSW) System..B 3.7.1-1 B 3.7.2 Diesel Generator Cooling Water (DGCW) System........B 3.7.2-1 B 3.7.3 Ultimate Heat Sink (UHS)............................B 3.7.3-1 B 3.7.4 Control Room Emergency Ventilation (CREV) System....B 3.7.4-1 (continued)
Quad Cities 1 and 2 iii Revision 0
TABLE OF CONTENTS
B 3.7 PLANT SYSTEMS (continued)
B 3.7.5 Control Room Emergency Ventilation Air Conditioning (AC) System..........................B 3.7.5-1 B 3.7.6 Main Condenser Offgas...............................B 3.7.6-1 B 3.7.7 Main Turbine Bypass System..........................B 3.7.7-1 B 3.7.8 Spent Fuel Storage Pool Water Level.................B 3.7.8-1 B 3.7.9 Safe Shutdown Makeup Pump (SSMP) System.............B 3.7.9-1
B 3.8 ELECTRICAL POWER SYSTEMS B 3.8.1 AC Sources-Operating................................B 3.8.1-1 B 3.8.2 AC Sources-Shutdown.................................B 3.8.2-1 B 3.8.3 Diesel Fuel Oil Properties and Starting Air.........B 3.8.3-1 B 3.8.4 DC Sources-Operating................................B 3.8.4-1 B 3.8.5 DC Sources-Shutdown.................................B 3.8.5-1 B 3.8.6 Battery Cell Parameters.............................B 3.8.6-1 B 3.8.7 Distribution Systems-Operating......................B 3.8.7-1 B 3.8.8 Distribution Systems-Shutdown.......................B 3.8.8-1
B 3.9 REFUELING OPERATIONS B 3.9.1 Refueling Equipment Interlocks......................B 3.9.1-1 B 3.9.2 Refuel Position One-Rod-Out Interlock...............B 3.9.2-1 B 3.9.3 Control Rod Position................................B 3.9.3-1 B 3.9.4 Control Rod Position Indication.....................B 3.9.4-1 B 3.9.5 Control Rod OPERABILITY-Refueling...................B 3.9.5-1 B 3.9.6 Reactor Pressure Vessel (RPV) Water Level-Irradiated Fuel.............................B 3.9.6-1 B 3.9.7 Reactor Pressure Vessel (RPV) Water Level-New Fuel or Control Rods..............................B 3.9.7-1 B 3.9.8 Residual Heat Removal (RHR)-High Water Level........B 3.9.8-1 B 3.9.9 Residual Heat Removal (RHR)-Low Water Level.........B 3.9.9-1
B 3.10 SPECIAL OPERATIONS B 3.10.1 Reactor Mode Switch Interlock Testing...............B 3.10.1-1 B 3.10.2 Single Control Rod Withdrawal-Hot Shutdown..........B 3.10.2-1 B 3.10.3 Single Control Rod Withdrawal-Cold Shutdown.........B 3.10.3-1 B 3.10.4 Single Control Rod Drive (CRD) Removal-Refueling.................................B 3.10.4-1 B 3.10.5 Multiple Control Rod Withdrawal-Refueling...........B 3.10.5-1 B 3.10.6 Control Rod Testing-Operating.......................B 3.10.6-1 B 3.10.7 SHUTDOWN MARGIN (SDM) Test-Refueling................B 3.10.7-1
Quad Cities 1 and 2 B 2.1.1-1 Revision 0 Reactor Core SLs B 2.1.1
B 2.0 SAFETY LIMITS (SLs)
B 2.1.1 Reactor Core SLs
BASES BACKGROUND UFSAR Section 3.1.2.1 (Ref. 1) requires, and SLs ensure, that specified acceptable fuel design limits are not exceeded during steady state operation, normal operational
transients, and anticipated operational occurrences (AOOs).
The fuel cladding integrity SL is set such that no
significant fuel damage is calculated to occur if the limit
is not violated. Because fuel damage is not directly
observable, a stepback approach is used to establish an SL, such that the MCPR is not less than the limit specified in
Specification 2.1.1.2. MCPR greater than the specified
limit represents a conservative margin relative to the
conditions required to maintain fuel cladding integrity.
The fuel cladding is one of the physical barriers that
separate the radioactive materials from the environs. The
integrity of this cladding barrier is related to its
relative freedom from perforations or cracking. Although
some corrosion or use related cracking may occur during the
life of the cladding, fission product migration from this
source is incrementally cumulative and continuously
measurable. Fuel cladding perforations, however, can result
from thermal stresses, which occur from reactor operation
significantly above design conditions.
While fission product migration from cladding perforation is
just as measurable as that from use related cracking, the
thermally caused cladding perforations signal a threshold
beyond which still greater thermal stresses may cause gross, rather than incremental, cladding deterioration. Therefore, the fuel cladding SL is defined with a margin to the
conditions that would produce onset of transition boiling (i.e., MCPR = 1.00). These conditions represent a
significant departure from the condition intended by design
for planned operation. The MCPR fuel cladding integrity SL
ensures that during normal operation and during AOOs, at
least 99.9% of the fuel rods in the core do not experience
transition boiling.
(continued)
Reactor Core SLs B 2.1.1
Quad Cities 1 and 2 B 2.1.1-2 Revision 0 BASES BACKGROUND Operation above the boundary of the nucleate boiling regime (continued) could result in excessive cladding temperature because of the onset of transition boiling and the resultant sharp
reduction in heat transfer coefficient. Inside the steam
film, high cladding temperatures are reached, and a cladding
water (zirconium water) reaction may take place. This
chemical reaction results in oxidation of the fuel cladding
to a structurally weaker form. This weaker form may lose
its integrity, resulting in an uncontrolled release of
activity to the reactor coolant.
The reactor vessel water level SL ensures that adequate core
cooling capability is maintained during all MODES of reactor
operation. Establishment of Emergency Core Cooling System
initiation setpoints higher than this SL provides margin
such that the SL will not be reached or exceeded.
APPLICABLE The fuel cladding must not sustain damage as a result of SAFETY ANALYSES normal operation and AOOs. The reactor core SLs are established to preclude violation of the fuel design
criterion that a MCPR limit is to be established, such that
at least 99.9% of the fuel rods in the core would not be
expected to experience the onset of transition boiling.
The Reactor Protection System setpoints (LCO 3.3.1.1, "Reactor Protection System (RPS) Instrumentation"), in
combination with the other LCOs, are designed to prevent any
anticipated combination of transient conditions for Reactor
Coolant System water level, pressure, and THERMAL POWER
level that would result in reaching the MCPR Safety Limit.
Cores with fuel that is all from one vendor utilize that
vendor's critical power correlation for determination of
MCPR. For cores with fuel from more than one vendor, the
MCPR is calculated for all fuel in the core using the
licensed critical power correlations. This may be
accomplished by using each vendor's correlation for the
vendor's respective fuel. Alternatively, a single
correlation can be used for all fuel in the core. For fuel
that has not been manufactured by the vendor supplying the
critical power correlation, the input parameters to the
reload vendor's correlation are adjusted using benchmarking
data to yield conservative results compared with the
critical power results from the co-resident fuel.
(continued)
Reactor Core SLs B 2.1.1
Quad Cities 1 and 2 B 2.1.1-3 Revision 28 BASES APPLICABLE 2.1.1.1 Fuel Cladding Integrity SAFETY ANALYSES (continued) The use of the Siemens Power Corporation correlation (ANFB) is valid for critical power calculations at pressures
> 600 psia and bundle mass fluxes > 0.1 x 10 6 lb/hr-ft 2 (Refs. 2 and 3). The use of the General Electric (GE)
Critical Power correlation (GEXL) is valid for critical
power calculations at pressures > 785 psig and core flows
> 10% (Ref. 4). The use of the Westinghouse critical power correlation (D4.1.1) is valid for critical power calculations at pressures > 362 psia and bundle mass fluxes
> 0.23 x 10 6 lb/hr-ft 2 (Ref. 8). For operation at low pressures or low flows, the fuel cladding integrity SL is
established by a limiting condition on core THERMAL POWER, with the following basis:
Since the pressure drop in the bypass region is
essentially all elevation head, the core pressure drop
at low power and flows will always be > 4.5 psi.
Analyses show that with a bundle flow of 28 x 10 3 lb/hr (approximately a mass velocity of
0.25 X 10 6 lb/hr-ft 2), bundle pressure drop is nearly independent of bundle power and has a value of
3.5 psi. Thus, the bundle flow with a 4.5 psi driving
head will be > 28 x 10 3 lb/hr. Full scale critical power test data taken at pressures from 14.7 psia to
800 psia indicate that the fuel assembly critical
power at this flow is approximately 3.35 MWt. With
the design peaking factors, this corresponds to a
THERMAL POWER > 50 % RTP. Thus, a THERMAL POWER limit
of 25% RTP for reactor pressure < 785 psig is
conservative. Although the ANFB correlation is valid
at reactor steam dome pressures > 600 psia, and the Westinghouse D4.1.1 correlation is valid at reactor steam dome pressures > 362 psia, application of the fuel cladding integrity SL at reactor steam dome
pressure < 785 psig is conservative.
2.1.1.2 MCPR The MCPR SL ensures sufficient conservatism in the operating
MCPR limit that, in the event of an AOO from the limiting
condition of operation, at least 99.9% of the fuel rods in
(continued)
Reactor Core SLs B 2.1.1
Quad Cities 1 and 2 B 2.1.1-4 Revision 28 BASES APPLICABLE 2.1.1.2 MCPR (continued)
SAFETY ANALYSES the core would be expected to avoid boiling transition. The margin between calculated boiling transition (i.e.,
MCPR = 1.00) and the MCPR SL is based on a detailed
statistical procedure that considers the uncertainties in
monitoring the core operating state. One specific
uncertainty included in the SL is the uncertainty inherent
in the fuel vendor's critical power correlation.
References 2, 3, 4, 5, 6, and 9 describe the methodology used in determining the MCPR SL.
The fuel vendor's critical power correlation is based on a
significant body of practical test data, providing a high
degree of assurance that the critical power, as evaluated by
the correlation, is within a small percentage of the actual
critical power being estimated. As long as the core
pressure and flow are within the range of validity of the
correlation, the assumed reactor conditions used in defining
the SL introduce conservatism into the limit because
bounding high radial power factors and bounding flat local
peaking distributions are used to estimate the number of
rods in boiling transition. These conservatisms and the
inherent accuracy of the fuel vendor's correlation provide a
reasonable degree of assurance that there would be no
transition boiling in the core during sustained operation at
the MCPR SL. If boiling transition were to occur, there is
reason to believe that the integrity of the fuel would not
be compromised. Significant test data accumulated by the
NRC and private organizations indicate that the use of a
boiling transition limitation to protect against cladding
failure is a very conservative approach. Much of the data
indicate that BWR fuel can survive for an extended period of
time in an environment of boiling transition.
2.1.1.3 Reactor Vessel Water Level
During MODES 1 and 2 the reactor vessel water level is
required to be above the top of the active irradiated fuel
to provide core cooling capability. With fuel in the
reactor vessel during periods when the reactor is shut down, consideration must be given to water level requirements due
to the effect of decay heat. If the water level should drop
below the top of the active irradiated fuel during this
(continued)
Reactor Core SLs B 2.1.1
Quad Cities 1 and 2 B 2.1.1-5 Revision 31 BASES APPLICABLE 2.1.1.3 Reactor Vessel Water Level (continued)
SAFETY ANALYSES period, the ability to remove decay heat is reduced. This reduction in cooling capability could lead to elevated
cladding temperatures and clad perforation in the event that
the water level becomes < 2/3 of the core height. The
reactor vessel water level SL has been established at the
top of the active irradiated fuel to provide a point that
can be monitored and to also provide adequate margin for
effective action.
SAFETY LIMITS The reactor core SLs are established to protect the integrity of the fuel clad barrier to prevent the release of
radioactive materials to the environs. SL 2.1.1.1 and
SL 2.1.1.2 ensure that the core operates within the fuel
design criteria. SL 2.1.1.3 ensures that the reactor vessel
water level is greater than the top of the active irradiated
fuel in order to prevent elevated clad temperatures and
resultant clad perforations.
APPLICABILITY SLs 2.1.1.1, 2.1.1.2, and 2.1.1.3 are applicable in all MODES.
SAFETY LIMIT 2.2 VIOLATIONS Exceeding an SL may cause fuel damage and create a potential
for radioactive releases in excess of 10 CFR 50.67, "Accident Source Term," limits (Ref. 7). Therefore, it is required to insert all insertable control rods and restore
compliance with the SLs within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. The 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />
Completion Time ensures that the operators take prompt
remedial action and also ensures that the probability of an
accident occurring during this period is minimal.
(continued)
Reactor Core SLs B 2.1.1
Quad Cities 1 and 2 B 2.1.1-6 Revision 31 BASES (continued)
REFERENCES 1. UFSAR, Section 3.1.2.1.
- 2. ANF-524(P)(A), Revision 2, Supplement 1, Revision 2, Supplement 2, Advanced Nuclear Fuels Corporation
Critical Power Methodology for Boiling Water
Reactors/Advanced Nuclear Fuels Corporation Critical
Power Methodology for Boiling Water Reactors:
Methodology for Analysis of Assembly Channel Bowing
Effects/NRC Correspondence, (as specified in Technical
Specification 5.6.5).
- 3. ANF-1125(P)(A) and Supplements 1 and 2, ANFB Critical Power Correlation, Advanced Nuclear Fuels Corporation, (as specified in Technical Specification 5.6.5).
- 4. NEDE-24011-P-A, "General Electric Standard Application for Reactor Fuel (GESTAR)" (as specified in Technical
Specification 5.6.5).
- 5. ANF-1125(P)(A), Supplement 1, Appendix E, ANFB Critical Power Correlation Determination of ATRIUM-9B
Additive Constant Uncertainties, Siemens Power
Corporation, (as specified in Technical Specification
5.6.5).
- 6. EMF-1125(P)(A), Supplement 1, Appendix C, ANFB Critical Power Correlation Application for Coresident
Fuel, Siemens Power Corporation, (as specified in
Technical Specification 5.6.5).
- 7. 10 CFR 50.67.
- 8. WCAP-16081-P-A, "10x10 SVEA Fuel Critical Power Experiments and CPR Correlation: SVEA-96 Optima2" (as
specified in Technical Specification 5.6.5).
- 9. CENPD-300-P-A, "Reference Safety Report for Boiling Water Reactor Reload Fuel" (as specified in Technical
Specification 5.6.5).
Quad Cities 1 and 2 B 2.1.2-1 Revision 31 RCS Pressure SL B 2.1.2
B 2.0 SAFETY LIMITS (SLs)
B 2.1.2 Reactor Coolant System (RCS) Pressure SL
BASES BACKGROUND The SL on reactor steam dome pressure protects the RCS against overpressurization. In the event of fuel cladding failure, fission products are released into the reactor
coolant. The RCS then serves as the primary barrier in
preventing the release of fission products into the
atmosphere. Establishing an upper limit on reactor steam
dome pressure ensures continued RCS integrity. According to
UFSAR Sections 3.1.2.4, 3.1.5.6, 3.1.6.1, 3.1.6.2, and
3.1.6.4 (Ref. 1), the reactor coolant pressure boundary (RCPB) shall be designed with sufficient margin to ensure
that the design conditions are not exceeded during normal
operation and anticipated operational occurrences (AOOs).
During normal operation and AOOs, RCS pressure is limited
from exceeding the design pressure by more than 10%, in
accordance with Section III of the ASME Code (Ref. 2) for
the pressure vessel, and by more than 20%, in accordance
with USAS B31.1-1967 Code (Ref. 3) for the RCS piping. To
ensure system integrity, all RCS components are
hydrostatically tested at 125% of design pressure, in
accordance with ASME Code requirements, prior to initial
operation when there is no fuel in the core. Following
inception of unit operation, RCS components shall be
pressure tested in accordance with the requirements of ASME
Code,Section XI (Ref. 4).
Overpressurization of the RCS could result in a breach of
the RCPB, reducing the number of protective barriers
designed to prevent radioactive releases from exceeding the
limits specified in 10 CFR 50.67, "Accident Source Term" (Ref. 5). If this occurred in conjunction with a fuel
cladding failure, fission products could enter the
containment atmosphere.
(continued)
Quad Cities 1 and 2 B 2.1.2-2 Revision 31 BASES (continued)
APPLICABLE The RCS safety/relief valves and the Reactor Protection SAFETY ANALYSES System Reactor Vessel Steam Dome Pressure-High Function have settings established to ensure that the RCS pressure SL
will not be exceeded.
The RCS pressure SL has been selected such that it is at a
pressure below which it can be shown that the integrity of
the system is not endangered. The reactor pressure vessel
is designed to Section III of the ASME, Boiler and Pressure
Vessel Code, 1965 Edition, including Addenda through the
summer of 1967 (Ref. 6), which permits a maximum pressure
transient of 110%, 1375 psig, of design pressure 1250 psig.
The SL of 1345 psig, as measured in the reactor steam dome, is equivalent to 1375 psig at the lowest elevation of the
RCS. The RCS is designed to the USAS Power Piping Code, Section B31.1, 1967 Edition (Ref. 3), for the reactor
recirculation piping, which permits a maximum pressure
transient of 120% of design pressures of 1175 psig for
suction piping and 1325 psig for discharge piping. The RCS
pressure SL is selected to be the lowest transient
overpressure allowed by the applicable codes.
SAFETY LIMITS The maximum transient pressure allowable in the RCS pressure vessel under the ASME Code,Section III, is 110% of design pressure. The maximum transient pressure allowable in the
RCS piping, valves, and fittings is 120% of design pressures
of 1175 psig for suction piping and 1325 psig for discharge
piping. The most limiting of these allowances is the 110%
of the RCS pressure vessel design pressure; therefore, the
SL on maximum allowable RCS pressure is established at
1345 psig as measured at the reactor steam dome.
APPLICABILITY SL 2.1.2 applies in all MODES.
SAFETY LIMIT 2.2 VIOLATIONS Exceeding the RCS pressure SL may cause RCS failure and create a potential for radioactive releases in excess of
10 CFR 50.67, "Accident Source Term," limits (Ref. 5).
Therefore, it is required to insert all insertable control
rods and restore compliance with the SL within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. The (continued)
Quad Cities 1 and 2 B 2.1.2-3 Revision 31 BASES SAFETY LIMIT 2.2 (continued)
VIOLATIONS 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> Completion Time ensures that the operators take prompt remedial action and also assures that the probability
of an accident occurring during this period is minimal.
REFERENCES 1. UFSAR Sections 3.1.2.4, 3.1.5.6, 3.1.6.1, 3.1.6.2, and 3.1.6.4.
- 2. ASME, Boiler and Pressure Vessel Code,Section III, Article NB-7000.
- 4. ASME, Boiler and Pressure Vessel Code,Section XI, Article IWB-5000.
- 5. 10 CFR 50.67.
- 6. ASME, Boiler and Pressure Vessel Code,Section III, 1965 Edition, Addenda summer of 1967.
LCO Applicability B 3.0 Quad Cities 1 and 2 B 3.0-1 Revision 0 B 3.0 LIMITING CONDITION FOR OPERATION (LCO) APPLICABILITY BASES LCOs LCO 3.0.1 through LCO 3.0.7 establish the general requirements applicable to all Specifications in Sections 3.1 through 3.10 and apply at all times, unless otherwise
stated. LCO 3.0.1 LCO 3.0.1 establishes the Applicability statement within each individual Specification as the requirement for when the LCO is required to be met (i.e., when the unit is in the
MODES or other specified conditions of the Applicability
statement of each Specification).
LCO 3.0.2 LCO 3.0.2 establishes that upon discovery of a failure to meet an LCO, the associated ACTIONS shall be met. The Completion Time of each Required Action for an ACTIONS
Condition is applicable from the point in time that an
ACTIONS Condition is entered. The Required Actions
establish those remedial measures that must be taken within
specified Completion Times when the requirements of an LCO
are not met. This Specification establishes that:
- a. Completion of the Required Actions within the specified Completion Times constitutes compliance with
a Specification; and
- b. Completion of the Required Actions is not required when an LCO is met within the specified Completion
Time, unless otherwise specified.
There are two basic types of Required Actions. The first
type of Required Action specifies a time limit in which the
LCO must be met. This time limit is the Completion Time to
restore an inoperable system or component to OPERABLE status
or to restore variables to within specified limits. If this
type of Required Action is not completed within the
specified Completion Time, a shutdown may be required to
place the unit in a MODE or condition in which the
Specification is not applicable. (Whether stated as a
Required Action or not, correction of the entered Condition
is an action that may always be considered upon entering
ACTIONS.) The second type of Required Action specifies the
remedial measures that permit continued operation of the (continued)
LCO Applicability B 3.0 Quad Cities 1 and 2 B 3.0-2 Revision 0 BASES LCO 3.0.2 unit that is not further restricted by the Completion Time. (continued) In this case, compliance with the Required Actions provides an acceptable level of safety for continued operation.
Completing the Required Actions is not required when an LCO
is met or is no longer applicable, unless otherwise stated
in the individual Specifications.
The nature of some Required Actions of some Conditions
necessitates that, once the Condition is entered, the
Required Actions must be completed even though the
associated Condition no longer exists. The individual LCO's
ACTIONS specify the Required Actions where this is the case.
An example of this is in LCO 3.4.9, "RCS Pressure and
Temperature (P/T) Limits."
The Completion Times of the Required Actions are also
applicable when a system or component is removed from
service intentionally. The reasons for intentionally
relying on the ACTIONS include, but are not limited to, performance of Surveillances, preventive maintenance, corrective maintenance, or investigation of operational
problems. Entering ACTIONS for these reasons must be done
in a manner that does not compromise safety. Intentional
entry into ACTIONS should not be made for operational
convenience. Additionally, if intentional entry into
ACTIONS would result in redundant equipment being
inoperable, alternatives should be used instead. Doing so
limits the time both subsystems/divisions of a safety
function are inoperable and limits the time conditions exist
which may result in LCO 3.0.3 being entered. Individual
Specifications may specify a time limit for performing an SR
when equipment is removed from service or bypassed for
testing. In this case, the Completion Times of the Required
Actions are applicable when this time limit expires, if the
equipment remains removed from service or bypassed.
When a change in MODE or other specified condition is
required to comply with Required Actions, the unit may enter
a MODE or other specified condition in which another
Specification becomes applicable. In this case, the
Completion Times of the associated Required Actions would
apply from the point in time that the new Specification
becomes applicable and the ACTIONS Condition(s) are entered.
(continued)
LCO Applicability B 3.0 Quad Cities 1 and 2 B 3.0-3 Revision 0 BASES (continued)
LCO 3.0.3 LCO 3.0.3 establishes the actions that must be implemented when an LCO is not met and:
- a. An associated Required Action and Completion Time is not met and no other Condition applies; or
- b. The condition of the unit is not specifically addressed by the associated ACTIONS. This means that
no combination of Conditions stated in the ACTIONS can
be made that exactly corresponds to the actual
condition of the unit. Sometimes, possible
combinations of Conditions are such that entering
LCO 3.0.3 is warranted; in such cases, the ACTIONS
specifically state a Condition corresponding to such
combinations and also that LCO 3.0.3 be entered
immediately.
This Specification delineates the time limits for placing
the unit in a safe MODE or other specified condition when
operation cannot be maintained within the limits for safe
operation as defined by the LCO and its ACTIONS. It is not
intended to be used as an operational convenience that
permits routine voluntary removal of redundant systems or
components from service in lieu of other alternatives that
would not result in redundant systems or components being
Upon entering LCO 3.0.3, 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> is allowed to prepare for an
orderly shutdown before initiating a change in unit
operation. This includes time to permit the operator to
coordinate the reduction in electrical generation with the
load dispatcher to ensure the stability and availability of
the electrical grid. The time limits specified to reach
lower MODES of operation permit the shutdown to proceed in a
controlled and orderly manner that is well within the
specified maximum cooldown rate and within the capabilities
of the unit, assuming that only the minimum required
equipment is OPERABLE. This reduces thermal stresses on
components of the Reactor Coolant System and the potential
for a plant upset that could challenge safety systems under
conditions to which this Specification applies. The use and
interpretation of specified times to complete the actions of
LCO 3.0.3 are consistent with the discussion of Section 1.3, Completion Times.
(continued)
LCO Applicability B 3.0 Quad Cities 1 and 2 B 3.0-4 Revision 0 BASES LCO 3.0.3 A unit shutdown required in accordance with LCO 3.0.3 may be (continued) terminated and LCO 3.0.3 exited if any of the following occurs: a. The LCO is now met.
- b. A Condition exists for which the Required Actions have now been performed.
- c. ACTIONS exist that do not have expired Completion Times. These Completion Times are applicable from the
point in time that the Condition is initially entered
and not from the time LCO 3.0.3 is exited.
The time limits of Specification 3.0.3 allow 37 hours4.282407e-4 days <br />0.0103 hours <br />6.117725e-5 weeks <br />1.40785e-5 months <br /> for
the unit to be in MODE 4 when a shutdown is required during
MODE 1 operation. If the unit is in a lower MODE of
operation when a shutdown is required, the time limit for
reaching the next lower MODE applies. If a lower MODE is
reached in less time than allowed, however, the total
allowable time to reach MODE 4, or other applicable MODE, is
not reduced. For example, if MODE 3 is reached in 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />, then the time allowed for reaching MODE 4 is the next
27 hours3.125e-4 days <br />0.0075 hours <br />4.464286e-5 weeks <br />1.02735e-5 months <br />, because the total time for reaching MODE 4 is not
reduced from the allowable limit of 37 hours4.282407e-4 days <br />0.0103 hours <br />6.117725e-5 weeks <br />1.40785e-5 months <br />. Therefore, if
remedial measures are completed that would permit a return
to MODE 1, a penalty is not incurred by having to reach a
lower MODE of operation in less than the total time allowed.
In MODES 1, 2, and 3, LCO 3.0.3 provides actions for
Conditions not covered in other Specifications. The
requirements of LCO 3.0.3 do not apply in MODES 4 and 5
because the unit is already in the most restrictive
Condition required by LCO 3.0.3. The requirements of
LCO 3.0.3 do not apply in other specified conditions of the
Applicability (unless in MODE 1, 2, or 3) because the
ACTIONS of individual Specifications sufficiently define the
remedial measures to be taken.
Exceptions to LCO 3.0.3 are provided in instances where
requiring a unit shutdown, in accordance with LCO 3.0.3, would not provide appropriate remedial measures for the
associated condition of the unit. An example of this is in
LCO 3.7.8, "Spent Fuel Storage Pool Water Level." LCO 3.7.8
has an Applicability of "During movement of irradiated fuel
(continued)
LCO Applicability B 3.0 Quad Cities 1 and 2 B 3.0-5 Revision 22 BASES LCO 3.0.3 assemblies in the spent fuel storage pool." Therefore, this (continued) LCO can be applicable in any or all MODES. If the LCO and the Required Actions of LCO 3.7.8 are not met while in
MODE 1, 2, or 3, there is no safety benefit to be gained by
placing the unit in a shutdown condition. The Required
Action of LCO 3.7.8 of "Suspend movement of fuel assemblies
in the spent fuel storage pool" is the appropriate Required
Action to complete in lieu of the actions of LCO 3.0.3.
These exceptions are addressed in the individual
Specifications.
LCO 3.0.4 LCO 3.0.4 establishes limitations on changes in MODES or other specified conditions in the Applicability when an LCO is not met. It allows placing the unit in a MODE or other specified condition stated in that Applicability (e.g., the Applicability desired to be entered) when unit conditions are such that the requirements of the LCO would not be met, in accordance with LCO 3.0.4.a, LCO 3.0.4.b, or LCO 3.0.4.c.
LCO 3.0.4.a allows entry into a MODE or other specified condition in the Applicability with the LCO not met when the associated ACTIONS to be entered permit continued operation in the MODE or other specified condition in the Applicability for an unlimited period of time. Compliance with Required Actions that permit continued operation of the unit for an unlimited period of time in a MODE or other specified condition provides an acceptable level of safety for continued operation. This is without regard to the status of the unit before or after the MODE change.
Therefore, in such cases, entry into a MODE or other specified condition in the Applicability may be made in accordance with the provisions of the Required Actions.
LCO 3.0.4.b allows entry into a MODE or other specified condition in the Applicability with the LCO not met after performance of a risk assessment addressing inoperable systems and components, consideration of the results, determination of the acceptability of entering the MODE or other specified condition in the Applicability, and establishment of risk management actions, if appropriate.
The risk assessment may use quantitative, qualitative, or blended approaches, and the risk assessment will be conducted using the plant program, procedures, and criteria in place to implement 10 CFR 50.65(a)(4), which requires (continued)
LCO Applicability B 3.0 Quad Cities 1 and 2 B 3.0-6 Revision 22 BASES LCO 3.0.4 that risk impacts of maintenance activities to be assessed (continued) and managed. The risk assessment, for the purposes of LCO 3.0.4 (b), must take into account all inoperable Technical Specification equipment regardless of whether the equipment is included in the normal 10 CFR 50.65(a)(4) risk assessment scope. The risk assessments will be conducted using the procedures and guidance endorsed by Regulatory Guide 1.182, "Assessing and Managing Risk Before Maintenance Activities at Nuclear Power Plants." Regulatory Guide 1.182 endorses the guidance in Section 11 of NUMARC 93-01, "Industry Guideline for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants." These documents address general guidance for conduct of the risk assessment, quantitative and qualitative guidelines for establishing risk management actions, and example risk management actions. These include actions to plan and conduct other activities in a manner that controls overall risk, increased risk awareness by shift and management personnel, actions to reduce the duration of the condition, actions to minimize the magnitude of risk increases (establishment of backup success paths or compensatory measures), and determination that the proposed MODE change is acceptable. Consideration should also be given to the probability of completing restoration such that the requirements of the LCO would be met prior to the expiration of ACTIONS Completion Times that would require exiting the Applicability. LCO 3.0.4.b may be used with single, or multiple systems and components unavailable.
NUMARC 93-01 provides guidance relative to consideration of simultaneous unavailability of multiple systems and components.
The results of the risk assessment shall be considered in determining the acceptability of entering the MODE or other specified condition in the Applicability, and any corresponding risk management actions. The LCO 3.0.4.b risk assessments do not have to be documented.
The Technical Specifications allow continued operation with equipment unavailable in MODE 1 for the duration of the Completion Time. Since this is allowable, and since in general the risk impact in that particular MODE bounds the risk of transitioning into and through the applicable MODES or other specified conditions in the Applicability of the LCO, the use of the LCO 3.0.4.b allowance should be generally acceptable, as long as the risk is assessed and managed as stated above.
(continued)
LCO Applicability B 3.0 Quad Cities 1 and 2 B 3.0-7 Revision 22 BASES LCO 3.0.4 However, there is a small subset of systems and components (continued) that have been determined to be more important to risk and use of the LCO 3.0.4.b allowance is prohibited. The LCOs governing these system and components contain Notes prohibiting the use of LCO 3.0.4.b by stating that LCO 3.0.4.b is not applicable.
LCO 3.0.4.c allows entry into a MODE or other specified condition in the Applicability with the LCO not met based on a Note in the Specification which states LCO 3.0.4.c is applicable. These specific allowances permit entry into MODES or other specified conditions in the Applicability when the associated ACTIONS to be entered do not provide for continued operation for an unlimited period of time and a risk assessment has not been performed. This allowance may apply to all the ACTIONS or to a specific Required Action of a Specification. The risk assessments performed to justify the use of LCO 3.0.4.b usually only consider systems and components. For this reason, LCO 3.0.4.c is typically applied to Specifications which describe values and parameters (e.g., Drywell Air Temperature, Drywell Pressure, MCPR), and may be applied to other Specifications based on NRC plant-specific approval.
The provisions of this Specification should not be interpreted as endorsing the failure to exercise the good practice of restoring systems or components to OPERABLE status before entering an associated MODE or other specified condition in the Applicability.
The provisions of LCO 3.0.4 shall not prevent changes in MODES or other specified conditions in the Applicability that are required to comply with ACTIONS. In addition, the provisions of LCO 3.0.4 shall not prevent changes in MODES or other specified conditions in the Applicability that result from any unit shutdown. In this context, a unit shutdown is defined as a change in MODE or other specified condition in the Applicability associated with transitioning from MODE 1 to MODE 2, MODE 2 to MODE 3, and MODE 3 to MODE
- 4. (continued)
LCO Applicability B 3.0 Quad Cities 1 and 2 B 3.0-8 Revision 22 BASES LCO 3.0.4 Upon entry into a MODE or other specified condition in the (continued) Applicability with the LCO not met, LCO 3.0.1 and LCO 3.0.2 require entry into the applicable Conditions and Required Actions until the Condition is resolved, until the LCO is met, or until the unit is not within the Applicability of the Technical Specification.
Surveillances do not have to be performed on the associated inoperable equipment (or on variables outside the specified limits), as permitted by SR 3.0.1. Therefore, utilizing LCO 3.0.4 is not a violation of SR 3.0.1 or SR 3.0.4 for any Surveillances that have not been performed on inoperable equipment. However, SRs must be met to ensure OPERABILITY prior to declaring the associated equipment OPERABLE (or variable within limits) and restoring compliance with the affected LCO.
LCO 3.0.5 LCO 3.0.5 establishes the allowance for restoring equipment to service under administrative controls when it has been removed from service or declared inoperable to comply with
ACTIONS. The sole purpose of this Specification is to
provide an exception to LCO 3.0.2 (e.g., to not comply with
the applicable Required Action(s)) to allow the performance
of required testing to demonstrate:
- a. The OPERABILITY of the equipment being returned to service; or
- b. The OPERABILITY of other equipment.
The administrative controls ensure the time the equipment is
returned to service in conflict with the requirements of the
ACTIONS is limited to the time absolutely necessary to
perform the required testing to demonstrate OPERABILITY.
This Specification does not provide time to perform any
other preventive or corrective maintenance.
An example of demonstrating the OPERABILITY of the equipment
being returned to service is reopening a containment
isolation valve that has been closed to comply with Required
Actions and must be reopened to perform the required
testing.
(continued)
LCO Applicability B 3.0 Quad Cities 1 and 2 B 3.0-9 Revision 22 BASES LCO 3.0.5 An example of demonstrating the OPERABILITY of other (continued) equipment is taking an inoperable channel or trip system out of the tripped condition to prevent the trip function from
occurring during the performance of required testing on
another channel in the other trip system. A similar example
of demonstrating the OPERABILITY of other equipment is
taking an inoperable channel or trip system out of the
tripped condition to permit the logic to function and
indicate the appropriate response during the performance of
required testing on another channel in the same trip system.
LCO 3.0.6 LCO 3.0.6 establishes an exception to LCO 3.0.2 for support systems that have an LCO specified in the Technical Specifications (TS). This exception is provided because
LCO 3.0.2 would require that the Conditions and Required
Actions of the associated inoperable supported system's LCO
be entered solely due to the inoperability of the support
system. This exception is justified because the actions
that are required to ensure the plant is maintained in a
safe condition are specified in the support system LCO's
Required Actions. These Required Actions may include
entering the supported system's Conditions and Required
Actions or may specify other Required Actions.
When a support system is inoperable and there is an LCO specified for it in the TS, the supported system(s) are
required to be declared inoperable if determined to be
inoperable as a result of the support system inoperability. However, it is not necessary to enter into the supported systems' Conditions and Required Actions unless directed to
do so by the support system's Required Actions. The
potential confusion and inconsistency of requirements
related to the entry into multiple support and supported
systems' LCO's Conditions and Required Actions are
eliminated by providing all the actions that are necessary
to ensure the plant is maintained in a safe condition in the
support system's Required Actions.
However, there are instances where a support system's
Required Action may either direct a supported system to be
declared inoperable or direct entry into Conditions and
Required Actions for the supported system. This may occur
immediately or after some specified delay to perform some
other Required Action. Regardless of whether it is
immediate or after some delay, when a support system's
(continued)
LCO Applicability B 3.0 Quad Cities 1 and 2 B 3.0-10 Revision 22 BASES LCO 3.0.6 Required Action directs a supported system to be declared (continued) inoperable or directs entry into Conditions and Required Actions for a supported system, the applicable Conditions
and Required Actions shall be entered in accordance with
Specification 5.5.11, "Safety Function Determination Program (SFDP)," ensures loss of safety function is detected and
appropriate actions are taken. Upon entry into LCO 3.0.6, an evaluation shall be made to determine if loss of safety
function exists. Additionally, other limitations, remedial
actions, or compensatory actions may be identified as a
result of the support system inoperability and corresponding
exception to entering supported system Conditions and
Required Actions. The SFDP implements the requirements of
Cross division checks to identify a loss of safety function
for those support systems that support safety systems are
required. The cross division check verifies that the
supported systems of the redundant OPERABLE support system
are OPERABLE, thereby ensuring safety function is retained.
If this evaluation determines that a loss of safety function
exists, the appropriate Conditions and Required Actions of
the LCO in which the loss of safety function exists are
required to be entered.
This loss of safety function does not require the assumption of additional single failures or loss of offsite power.
Since operation is being restricted in accordance with the
ACTIONS of the support system, any resulting temporary loss
of redundancy or single failure protection is taken into
account. Similarly, the ACTIONS for inoperable offsite
circuit(s) and inoperable diesel generator(s) provide the
necessary restriction for cross division inoperabilities.
This explicit cross division verification for inoperable AC
electrical power sources also acknowledges that supported
system(s) are not declared inoperable solely as a result of
inoperability of a normal or emergency electrical power
source (refer to the definition of OPERABLE-OPERABILITY).
When a loss of safety function is determined to exist, and
the SFDP requires entry into the appropriate Conditions and
Required Actions of the LCO in which the loss of safety
function exists, consideration must be given to the specific
type of function affected. Where a loss of function is (continued)
LCO Applicability B 3.0 Quad Cities 1 and 2 B 3.0-11 Revision 22 BASES LCO 3.0.6 solely due to a single Technical Specification support (continued) system (e.g., loss of automatic start due to inoperable instrumentation, or loss of pump suction source due to low
tank level) the appropriate LCO is the LCO for the support
system. The ACTIONS for a support system LCO adequately
addresses the inoperabilities of that system without
reliance on entering its supported system LCO. When the
loss of function is the result of multiple support systems, the appropriate LCO is the LCO for the supported system.
LCO 3.0.7 There are certain special tests and operations required to be performed at various times over the life of the unit.
These special tests and operations are necessary to
demonstrate select unit performance characteristics, to
perform special maintenance activities, and to perform
special evolutions. Special Operations LCOs in Section 3.10
allow specified TS requirements to be changed to permit
performances of these special tests and operations, which
otherwise could not be performed if required to comply with
the requirements of these TS. Unless otherwise specified, all the other TS requirements remain unchanged. This will
ensure all appropriate requirements of the MODE or other
specified condition not directly associated with or required
to be changed to perform the special test or operation will
remain in effect.
The Applicability of a Special Operations LCO represents a condition not necessarily in compliance with the normal requirements of the TS. Compliance with Special Operations
LCOs is optional. A special operation may be performed
either under the provisions of the appropriate Special
Operations LCO or under the other applicable TS
requirements. If it is desired to perform the special
operation under the provisions of the Special Operations
LCO, the requirements of the Special Operations LCO shall be
followed. When a Special Operations LCO requires another
LCO to be met, only the requirements of the LCO statement
are required to be met regardless of that LCO's
Applicability (i.e., should the requirements of this other
LCO not be met, the ACTIONS of the Special Operations LCO
apply, not the ACTIONS of the other LCO). However, there
are instances where the Special Operations LCO's ACTIONS may
direct the other LCOs' ACTIONS be met. The Surveillances of
the other LCO are not required to be met, unless specified (continued)
LCO Applicability B 3.0 Quad Cities 1 and 2 B 3.0-12 Revision 22 BASES LCO 3.0.7 in the Special Operations LCO. If conditions exist such (continued) that the Applicability of any other LCO is met, all the other LCO's requirements (ACTIONS and SRs) are required to
be met concurrent with the requirements of the Special
Operations LCO.
LCO 3.0.8 LCO 3.0.8 establishes the applicability of each Specification to both Unit 1 and Unit 2 operation. Whenever a requirement applies to only one unit, or is different for
each unit, this will be identified in the appropriate
section of the Specification (e.g., Applicability, Surveillance, etc.) with parenthetical reference, Notes, or
other appropriate presentation within the body of the
requirement.
SR Applicability B 3.0 Quad Cities 1 and 2 B 3.0-13 Revision 22 B 3.0 SURVEILLANCE REQUIREMENT (SR) APPLICABILITY
BASES SRs SR 3.0.1 through SR 3.0.4 establish the general requirements applicable to all Specifications in Sections 3.1 through 3.10 and apply at all times, unless otherwise stated.
SR 3.0.1 SR 3.0.1 establishes the requirement that SRs must be met during the MODES or other specified conditions in the Applicability for which the requirements of the LCO apply, unless otherwise specified in the individual SRs. This
Specification is to ensure that Surveillances are performed
to verify the OPERABILITY of systems and components, and
that variables are within specified limits. Failure to meet
a Surveillance within the specified Frequency, in accordance
with SR 3.0.2, constitutes a failure to meet an LCO.
Systems and components are assumed to be OPERABLE when the
associated SRs have been met. Nothing in this
Specification, however, is to be construed as implying that
systems or components are OPERABLE when:
- a. The systems or components are known to be inoperable, although still meeting the SRs; or
- b. The requirements of the Surveillance(s) are known to be not met between required Surveillance performances.
Surveillances do not have to be performed when the unit is
in a MODE or other specified condition for which the
requirements of the associated LCO are not applicable, unless otherwise specified. The SRs associated with a
Special Operations LCO are only applicable when the Special
Operations LCO is used as an allowable exception to the
requirements of a Specification.
Unplanned events may satisfy the requirements (including
applicable acceptance criteria) for a given SR. In this
case, the unplanned event may be credited as fulfilling the
performance of the SR.
(continued)
SR Applicability B 3.0 Quad Cities 1 and 2 B 3.0-14 Revision 22 BASES SR 3.0.1 Surveillances, including Surveillances invoked by Required (continued) Actions, do not have to be performed on inoperable equipment because the ACTIONS define the remedial measures that apply.
Surveillances have to be met and performed in accordance
with SR 3.0.2, prior to returning equipment to OPERABLE
status.
Upon completion of maintenance, appropriate post maintenance
testing is required to declare equipment OPERABLE. This
includes ensuring applicable Surveillances are not failed
and their most recent performance is in accordance with
SR 3.0.2. Post maintenance testing may not be possible in
the current MODE or other specified conditions in the
Applicability due to the necessary unit parameters not
having been established. In these situations, the equipment
may be considered OPERABLE provided testing has been
satisfactorily completed to the extent possible and the
equipment is not otherwise believed to be incapable of
performing its function. This will allow operation to
proceed to a MODE or other specified condition where other
necessary post maintenance tests can be completed.
Some examples of this process are:
- a. Control Rod Drive maintenance during refueling that requires scram testing at 800 psig. However, if other appropriate testing is satisfactorily completed
and the scram time testing of SR 3.1.4.3 is satisfied, the control rod can be considered OPERABLE. This
allows startup to proceed to reach 800 psig to perform
other necessary testing.
- b. High pressure coolant injection (HPCI) maintenance during shutdown that requires system functional tests
at a specified pressure. Provided other appropriate
testing is satisfactorily completed, startup can
proceed with HPCI considered OPERABLE. This allows
operation to reach the specified pressure to complete
the necessary post maintenance testing.
(continued)
SR Applicability B 3.0 Quad Cities 1 and 2 B 3.0-15 Revision 22 BASES (continued)
SR 3.0.2 SR 3.0.2 establishes the requirements for meeting the specified Frequency for Surveillances and any Required Action with a Completion Time that requires the periodic
performance of the Required Action on a "once per..."
interval.
SR 3.0.2 permits a 25% extension of the interval specified
in the Frequency. This extension facilitates Surveillance
scheduling and considers plant operating conditions that may
not be suitable for conducting the Surveillance (e.g.,
transient conditions or other ongoing Surveillance or
maintenance activities).
The 25% extension does not significantly degrade the
reliability that results from performing the Surveillance at
its specified Frequency. This is based on the recognition
that the most probable result of any particular Surveillance
being performed is the verification of conformance with the
SRs. The exceptions to SR 3.0.2 are those Surveillances for
which the 25% extension of the interval specified in the
Frequency does not apply. These exceptions are stated in
the individual Specifications. The requirements of
regulations take precedence over the TS. Therefore, when a
test interval is specified in the regulations, the test
interval cannot be extended by the TS, and the SR includes a
Note in the Frequency stating "SR 3.0.2 is not applicable."
As stated in SR 3.0.2, the 25% extension also does not apply
to the initial portion of a periodic Completion Time that
requires performance on a "once per..." basis. The 25%
extension applies to each performance after the initial
performance. The initial performance of the Required
Action, whether it is a particular Surveillance or some
other remedial action, is considered a single action with a
single Completion Time. One reason for not allowing the 25%
extension to this Completion Time is that such an action
usually verifies that no loss of function has occurred by
checking the status of redundant or diverse components or
accomplishes the function of the inoperable equipment in an
alternative manner.
The provisions of SR 3.0.2 are not intended to be used
repeatedly merely as an operational convenience to extend
Surveillance intervals (other than those consistent with (continued)
SR Applicability B 3.0 Quad Cities 1 and 2 B 3.0-16 Revision 22 BASES SR 3.0.2 refueling intervals) or periodic Completion Time intervals (continued) beyond those specified.
SR 3.0.3 SR 3.0.3 establishes the flexibility to defer declaring affected equipment inoperable or an affected variable outside the specified limits when a Surveillance has not
been completed within the specified Frequency. A delay
period of up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or up to the limit of the specified
Frequency, whichever is greater, applies from the point in
time that it is discovered that the Surveillance has not
been performed in accordance with SR 3.0.2, and not at the
time that the specified Frequency was not met. This delay
period provides adequate time to complete Surveillances that
have been missed. This delay period permits the completion
of a Surveillance before complying with Required Actions or
other remedial measures that might preclude completion of
the Surveillance.
The basis for this delay period includes consideration of
unit conditions, adequate planning, availability of
personnel, the time required to perform the Surveillance, the safety significance of the delay in completing the
required Surveillance, and the recognition that the most
probable result of any particular Surveillance being
performed is the verification of conformance with the
requirements.
When a Surveillance with a Frequency based not on time
intervals, but upon specified unit conditions, operating
situations, or requirements of regulations (e.g., prior to
entering MODE 1 after each fuel loading, or in accordance
with 10 CFR 50, Appendix J, as modified by approved
exemptions, etc.) is discovered to not have been performed
when specified, SR 3.03 allows for the full delay period of
up to the specified Frequency to perform the Surveillance.
However, since there is not a time interval specified, the
missed Surveillance should be performed at the first
reasonable opportunity.
SR 3.0.3 provides a time limit for, and allowances for the
performance of, Surveillances that become applicable as a
consequence of MODE changes imposed by Required Actions.
Failure to comply with specified Frequencies for SRs is
expected to be an infrequent occurrence. Use of the delay (continued)
SR Applicability B 3.0 Quad Cities 1 and 2 B 3.0-17 Revision 22 BASES SR 3.0.3 period established by SR 3.0.3 is a flexibility which is not (continued) intended to be used as an operational convenience to extend Surveillance intervals. While up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or the limit
of the specified Frequency is provided to perform the missed
Surveillance, it is expected that the missed Surveillance
will be performed at the first reasonable opportunity. The
determination of the first reasonable opportunity should
include consideration of the impact on plant risk (from
delaying the Surveillance as well as any plant configuration
changes required or shutting the plant down to perform the
Surveillance) and impact on any analysis assumptions, in
addition to unit conditions, planning, availability of
personnel, and the time required to perform the
Surveillance. This risk impact should be managed through
the program in place to implement 10 CFR 50.65(a)(4) and its
implementation guidance, NRC Regulatory Guide 1.182,
'Assessing and Managing Risk Before Maintenance Activities
at Nuclear Power Plants.' This Regulatory Guide addresses
consideration of temporary and aggregate risk impacts, determination of risk management action thresholds, and risk
management action up to and including plant shutdown. The
missed Surveillance should be treated as an emergent
condition as discussed in the Regulatory Guide. The risk
evaluation may use quantitative, qualitative, or blended
methods. The degree of depth and rigor of the evaluation
should be commensurate with the importance of the component.
Missed Surveillances for important components should be
analyzed quantitatively. If the results of the risk
evaluation determine the risk increase is significant, this
evaluation should be used to determine the safest course of
action. All missed Surveillances will be placed in the
licensee's Corrective Action Program.
If a Surveillance is not completed within the allowed delay period, then the equipment is considered inoperable or the variable is considered outside the specified limits and the
Completion Times of the Required Actions for the applicable
LCO Conditions begin immediately upon expiration of the
delay period. If a Surveillance is failed within the delay
period, then the equipment is inoperable, or the variable is
outside the specified limits and the Completion Times of the
Required Actions for the applicable LCO Conditions begin
immediately upon the failure of the Surveillance.
(continued)
SR Applicability B 3.0 Quad Cities 1 and 2 B 3.0-18 Revision 22 BASES SR 3.0.3 Completion of the Surveillance within the delay period (continued) allowed by this Specification, or within the Completion Time of the ACTIONS, restores compliance with SR 3.0.1.
SR 3.0.4 SR 3.0.4 establishes the requirement that all applicable SRs must be met before entry into a MODE or other specified condition in the Applicability.
This Specification ensures that system and component OPERABILITY requirements and variable limits are met before entry into MODES or other specified conditions in the Applicability for which these systems and components ensure safe operation of the unit. The provisions of this Specification should not be interpreted as endorsing the failure to exercise the good practice of restoring systems or components to OPERABLE status before entering an associated MODE or other specified condition in the Applicability.
A provision is included to allow entry into a MODE or other specified condition in the Applicability when an LCO is not met due to Surveillance not being met in accordance with LCO 3.0.4. However, in certain circumstances, failing to meet an SR will not result in SR 3.0.4 restricting a MODE change or other specified condition change. When a system, subsystem, division, component, device, or variable is inoperable or outside its specified limits, the associated SR(s) are not required to be performed, per SR 3.0.1, which states that surveillances do not have to be performed on inoperable equipment. When equipment is inoperable, SR 3.0.4 does not apply to the associated SR(s) since the requirement for the SR(s) to be performed is removed. Therefore, failing to perform the Surveillance(s) within the specified Frequency does not result in an SR 3.0.4 restriction to changing MODES or other specified conditions of the Applicability.
However, since the LCO is not met in this instance, LCO 3.0.4 will govern any restrictions that may (or may not) apply to MODE or other specified condition changes. SR 3.0.4 does not restrict changing MODES or other specified (continued)
SR Applicability B 3.0 Quad Cities 1 and 2 B 3.0-19 Revision 22 BASES SR 3.0.4 conditions of the Applicability when a Surveillance has not (continued) been performed within the specified Frequency, provided the requirement to declare the LCO not met has been delayed in accordance with SR 3.0.3.
The provisions of SR 3.0.4 shall not prevent entry into MODES or other specified conditions in the Applicability that are required to comply with ACTIONS. In addition, the provisions of SR 3.0.4 shall not prevent changes in MODES or other specified conditions in the Applicability that result from any unit shutdown. In this context, a unit shutdown is defined as a change in MODE or other specified condition in the Applicability associated with transitioning from MODE 1 to MODE 2, MODE 2 to MODE 3, and MODE 3 to MODE 4.
The precise requirements for performance of SRs are specified such that exceptions to SR 3.0.4 are not necessary. The specific time frames and conditions necessary for meeting the SRs are specified in the Frequency, in the Surveillance, or both. This allows performance of Surveillances when the prerequisite condition(s) specified in a Surveillance procedure require entry into the MODE or other specified condition in the Applicability of the associated LCO prior to the performance or completion of a Surveillance. A Surveillance that could not be performed until after entering the LCO's Applicability, would have its Frequency specified such that it is not "due" until the specific conditions needed are met. Alternately, the Surveillance may be stated in the form of a Note, as not required (to be met or performed) until a particular event, condition, or time has been reached. Further discussion of the specific formats of SRs' annotation is found in Section 1.4, Frequency.
SR 3.0.5 SR 3.0.5 establishes the applicability of each Surveillance to both Unit 1 and Unit 2 operation. Whenever a requirement applies to only one unit, or is different for each unit, this will be identified with parenthetical reference, Notes, or other appropriate presentation within the SR.
SDM B 3.1.1 Quad Cities 1 and 2 B 3.1.1-1 Revision 0 B 3.1 REACTIVITY CONTROL SYSTEMS
B 3.1.1 SHUTDOWN MARGIN (SDM)
BASES
BACKGROUND SDM requirements are specified to ensure:
- a. The reactor can be made subcritical from all operating conditions and transients and Design Basis Events;
- b. The reactivity transients associated with postulated accident conditions are controllable within acceptable
limits; and
- c. The reactor will be maintained sufficiently subcritical to preclude inadvertent criticality in the
shutdown condition.
These requirements are satisfied by the control rods, as
described in UFSAR, Sections 3.1.5 and 4.6.2.1 (Ref. 1),
which can compensate for the reactivity effects of the fuel
and water temperature changes experienced during all
operating conditions.
APPLICABLE Having sufficient SDM assures that the reactor will become SAFETY ANALYSES and remain subcritical after all design basis accidents and transients. For example, SDM is assumed as an initial
condition for the control rod removal error during refueling (Ref. 2) accident. The analysis of this reactivity
insertion event assumes the refueling interlocks are
OPERABLE when the reactor is in the refueling mode of
operation. These interlocks prevent the withdrawal of more
than one control rod from the core during refueling.
(Special consideration and requirements for multiple control
rod withdrawal during refueling are covered in Special
Operations LCO 3.10.5, "Multiple Control Rod Withdrawal-
Refueling.") The analysis assumes this condition is
acceptable since the core will be shut down with the highest
worth control rod withdrawn, if adequate SDM has been
demonstrated.
Prevention or mitigation of positive reactivity insertion
events is necessary to limit the energy deposition in the
fuel, thereby preventing significant fuel damage, which
(continued)
SDM B 3.1.1
Quad Cities 1 and 2 B 3.1.1-2 Revision 0 BASES APPLICABLE could result in undue release of radioactivity. Adequate SAFETY ANALYSES SDM ensures inadvertent criticalities do not cause (continued) significant fuel damage.
SDM satisfies Criterion 2 of 10 CFR 50.36(c)(2)(ii).
LCO The specified SDM limit accounts for the uncertainty in the demonstration of SDM by testing. Separate SDM limits are
provided for testing where the highest worth control rod is
determined analytically or by measurement. This is due to
the reduced uncertainty in the SDM test when the highest
worth control rod is determined by measurement. When SDM is
demonstrated by calculations not associated with a test (e.g., to confirm SDM during the fuel loading sequence),
additional margin is included to account for uncertainties
in the calculation. To ensure adequate SDM, a design margin
is included to account for uncertainties in the design
calculations (Ref. 3).
APPLICABILITY In MODES 1 and 2, SDM must be provided to assure shutdown capability. In MODES 3 and 4, SDM is required to ensure the
reactor will be held subcritical with margin for a single
withdrawn control rod. SDM is required in MODE 5 to prevent
an open vessel, inadvertent criticality during the
withdrawal of a single control rod from a core cell
containing one or more fuel assemblies (Ref. 2).
ACTIONS A.1 With SDM not within the limits of the LCO in MODE 1 or 2, SDM must be restored within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. Failure to meet the
specified SDM may be caused by a control rod that cannot be
inserted. The allowed Completion Time of 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> is
acceptable, considering that the reactor can still be shut
down, assuming no failures of additional control rods to
insert, and the low probability of an event occurring during
this interval.
(continued)
SDM B 3.1.1
Quad Cities 1 and 2 B 3.1.1-3 Revision 0 BASES ACTIONS B.1 (continued)
If the SDM cannot be restored, the plant must be brought to
MODE 3 in 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, to prevent the potential for further
reductions in available SDM (e.g., additional stuck control
rods). The allowed Completion Time of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> is
reasonable, based on operating experience, to reach MODE 3
from full power conditions in an orderly manner and without
challenging plant systems.
C.1 With SDM not within limits in MODE 3, the operator must
immediately initiate action to fully insert all insertable
control rods. Action must continue until all insertable
control rods are fully inserted. This action results in the
least reactive condition for the core.
D.1, D.2, D.3, and D.4
With SDM not within limits in MODE 4, the operator must
immediately initiate action to fully insert all insertable
control rods. Action must continue until all insertable
control rods are fully inserted. This action results in the
least reactive condition for the core. Action must also be
initiated within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> to provide means for control of
potential radioactive releases. This includes ensuring
secondary containment is OPERABLE; at least one Standby Gas
Treatment (SGT) subsystem is OPERABLE; and secondary
containment isolation capability is available in each
associated secondary containment penetration flow path not
isolated that is assumed to be isolated to mitigate
radioactivity releases (i.e., at least one secondary
containment isolation valve and associated instrumentation
are OPERABLE, or other acceptable administrative controls to
assure isolation capability). These administrative controls
consist of stationing a dedicated operator, who is in
continuous communication with the control room, at the
controls of the isolation device. In this way, the
penetration can be rapidly isolated when a need for
secondary containment isolation is indicated. This (ensuring components are OPERABLE) may be performed as an (continued)
SDM B 3.1.1
Quad Cities 1 and 2 B 3.1.1-4 Revision 0 BASES ACTIONS D.1, D.2, D.3, and D.4 (continued) administrative check, by examining logs or other
information, to determine if the components are out of
service for maintenance or other reasons. It is not
necessary to perform the surveillances needed to demonstrate
the OPERABILITY of the components. If, however, any
required component is inoperable, then it must be restored
to OPERABLE status. In this case, SRs may need to be
performed to restore the component to OPERABLE status.
Actions must continue until all required components are
OPERABLE E.1, E.2, E.3, E.4, and E.5
With SDM not within limits in MODE 5, the operator must
immediately suspend CORE ALTERATIONS that could reduce SDM (e.g., insertion of fuel in the core or the withdrawal of
control rods). Suspension of these activities shall not
preclude completion of movement of a component to a safe
condition. Inserting control rods or removing fuel from the
core will reduce the total reactivity and are therefore
excluded from the suspended actions.
Action must also be immediately initiated to fully insert
all insertable control rods in core cells containing one or
more fuel assemblies. Action must continue until all
insertable control rods in core cells containing one or more
fuel assemblies have been fully inserted. Control rods in
core cells containing no fuel assemblies do not affect the
reactivity of the core and therefore do not have to be
inserted.
Action must also be initiated within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> to provide means
for control of potential radioactive releases. This
includes ensuring secondary containment is OPERABLE; at
least one SGT subsystem is OPERABLE; and secondary
containment isolation capability is available in each
associated secondary containment penetration flow path not
isolated that is assumed to be isolated to mitigate
radioactivity releases (i.e., at least one secondary
containment isolation valve and associated instrumentation
are OPERABLE, or other acceptable administrative controls to
(continued)
SDM B 3.1.1
Quad Cities 1 and 2 B 3.1.1-5 Revision 0 BASES ACTIONS E.1, E.2, E.3, E.4, and E.5 (continued) assure isolation capability). These administrative controls
consist of stationing a dedicated operator, who is in
continuous communication with the control room, at the
controls of the isolation device. In this way, the
penetration can be rapidly isolated when a need for
secondary containment isolation is indicated. This (ensuring components are OPERABLE) may be performed as an
administrative check, by examining logs or other
information, to determine if the components are out of
service for maintenance or other reasons. It is not
necessary to perform the Surveillances as needed to
demonstrate the OPERABILITY of the components. If, however, any required component is inoperable, then it must be
restored to OPERABLE status. In this case, SRs may need to
be performed to restore the component to OPERABLE status.
Action must continue until all required components are
SURVEILLANCE SR 3.1.1.1 REQUIREMENTS Adequate SDM must be verified to ensure that the reactor can
be made subcritical from any initial operating condition.
This can be accomplished by a test, an evaluation, or a
combination of the two. Adequate SDM is demonstrated by
testing before or during the first startup after fuel
movement, shuffling within the reactor pressure vessel, or
control rod replacement. Control rod replacement refers to
the decoupling and removal of a control rod from a core
location, and subsequent replacement with a new control rod
or a control rod from another core location. Since core
reactivity will vary during the cycle as a function of fuel
depletion and poison burnup, the beginning of cycle (BOC)
test must also account for changes in core reactivity during
the cycle. Therefore, to obtain the SDM, the initial
measured value must be increased by an adder, "R", which is
the difference between the calculated value of maximum core
reactivity during the operating cycle and the calculated BOC
core reactivity. If the value of R is negative (that is, BOC is the most reactive point in the cycle), no correction
to the BOC measured value is required (Refs. 3 and 4). For (continued)
SDM B 3.1.1
Quad Cities 1 and 2 B 3.1.1-6 Revision 0 BASES SURVEILLANCE SR 3.1.1.1 (continued)
REQUIREMENTS the SDM demonstrations that rely solely on calculation of
the highest worth control rod, additional margin
(0.10% k/k) must be added to the SDM limit of 0.28% k/k to account for uncertainties in the calculation.
The SDM may be demonstrated during an in-sequence control
rod withdrawal, in which the highest worth control rod is
analytically determined, or during local criticals, where
the highest worth control rod is determined by testing.
Local critical tests require the withdrawal of out of
sequence control rods. This testing would therefore require
bypassing of the rod worth minimizer to allow the out of
sequence withdrawal, and therefore additional requirements
must be met (see LCO 3.10.6, "Control Rod
Testing-Operating").
The Frequency of 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after reaching criticality is
allowed to provide a reasonable amount of time to perform
the required calculations and have appropriate verification.
During MODES 3 and 4, analytical calculation of SDM may be
used to assure the requirements of SR 3.1.1.1 are met.
During MODE 5, adequate SDM is required to ensure that the
reactor does not reach criticality during control rod
withdrawals. An evaluation of each in-vessel fuel movement
during fuel loading (including shuffling fuel within the
core) is required to ensure adequate SDM is maintained
during refueling. This evaluation ensures that the
intermediate loading patterns are bounded by the safety
analyses for the final core loading pattern. For example, bounding analyses that demonstrate adequate SDM for the most
reactive configurations during the refueling may be
performed to demonstrate acceptability of the entire fuel
movement sequence. These bounding analyses include
additional margins to the associated uncertainties. Spiral
offload/reload sequences inherently satisfy the SR, provided
the fuel assemblies are reloaded in the same configuration
analyzed for the new cycle. Removing fuel from the core
will always result in an increase in SDM.
(continued)
SDM B 3.1.1
Quad Cities 1 and 2 B 3.1.1-7 Revision 0 BASES (continued)
REFERENCES 1. UFSAR, Sections 3.1.5 and 4.6.2.1.
- 2. UFSAR, Section 15.4.1.
- 3. UFSAR, Section 4.3.2.1.3.
- 4. NEDE-24011-P-A, "General Electric Standard Application for Reactor Fuel," (as specified in Technical
Specification 5.6.5).
Reactivity Anomalies B 3.1.2 Quad Cities 1 and 2 B 3.1.2-1 Revision 0 B 3.1 REACTIVITY CONTROL SYSTEMS
B 3.1.2 Reactivity Anomalies
BASES
BACKGROUND In accordance with UFSAR, Sections 3.1.5.1, 3.1.5.5, and 3.1.5.6 (Ref. 1), reactivity shall be controllable such that
subcriticality is maintained under cold conditions and
acceptable fuel design limits are not exceeded during normal
operation and anticipated operational occurrences.
Therefore, Reactivity Anomalies is used as a measure of the
predicted versus measured core reactivity during power
operation. The continual confirmation of core reactivity is
necessary to ensure that the Design Basis Accident (DBA) and
transient safety analyses remain valid. A large reactivity
anomaly could be the result of unanticipated changes in fuel
reactivity or control rod worth or operation at conditions
not consistent with those assumed in the predictions of core
reactivity, and could potentially result in a loss of SDM or
violation of acceptable fuel design limits. Comparing
predicted versus measured core reactivity validates the
nuclear methods used in the safety analysis and supports the
SDM demonstrations (LCO 3.1.1, "SHUTDOWN MARGIN (SDM)") in
assuring the reactor can be brought safely to cold, subcritical conditions.
When the reactor core is critical or in normal power
operation, a reactivity balance exists and the net
reactivity is zero. A comparison of predicted and measured
reactivity is convenient under such a balance, since
parameters are being maintained relatively stable under
steady state power conditions. The positive reactivity
inherent in the core design is balanced by the negative
reactivity of the control components, thermal feedback, neutron leakage, and materials in the core that absorb
neutrons, such as burnable absorbers, producing zero net
reactivity.
In order to achieve the required fuel cycle energy output, the uranium enrichment in the new fuel loading and the fuel
loaded in the previous cycles provide excess positive
reactivity beyond that required to sustain steady state
operation at the beginning of cycle (BOC). When the reactor
is critical at RTP and operating moderator temperature, the
excess positive reactivity is compensated by burnable (continued)
Reactivity Anomalies B 3.1.2 Quad Cities 1 and 2 B 3.1.2-2 Revision 0 BASES BACKGROUND absorbers (e.g., gadolinia), control rods, and whatever (continued) neutron poisons (mainly xenon and samarium) are present in the fuel.
The predicted core reactivity, as represented by k effective (k eff) is calculated by a 3D core simulator code as a function of cycle exposure. This calculation is performed
for projected operating states and conditions throughout the
cycle. The core reactivity is determined from k eff for actual plant conditions and is then compared to the
predicted value for the cycle exposure.
APPLICABLE Accurate prediction of core reactivity is either an explicit SAFETY ANALYSES or implicit assumption in the accident analysis evaluations (Ref. 2). In particular, SDM and reactivity transients, such as control rod withdrawal accidents or rod drop
accidents, are very sensitive to accurate prediction of core
reactivity. These accident analysis evaluations rely on
computer codes that have been qualified against available
test data, operating plant data, and analytical benchmarks.
Monitoring reactivity anomaly provides additional assurance
that the nuclear methods provide an accurate representation
of the core reactivity.
The comparison between measured and predicted initial core
reactivity provides a normalization for the calculational
models used to predict core reactivity. If the measured and
predicted core K eff for identical core conditions at BOC do not reasonably agree, then the assumptions used in the
reload cycle design analysis or the calculation models used
to predict core k eff may not be accurate. If reasonable agreement between measured and predicted core reactivity
exists at BOC, then the prediction may be normalized to the
measured value. Thereafter, any significant deviations in
the measured core k eff from the predicted core k eff that develop during fuel depletion may be an indication that the
assumptions of the DBA and transient analyses are no longer
valid, or that an unexpected change in core conditions has
occurred.
Reactivity Anomalies satisfies Criterion 2 of
(continued)
Reactivity Anomalies B 3.1.2 Quad Cities 1 and 2 B 3.1.2-3 Revision 0 BASES (continued)
LCO The reactivity anomaly limit is established to ensure plant operation is maintained within the assumptions of the safety
analyses. Large differences between monitored and predicted
core reactivity may indicate that the assumptions of the DBA
and transient analyses are no longer valid, or that the
uncertainties in the "Nuclear Design Methodology" are larger
than expected. A limit on the difference between the
monitored and the predicted core k eff of +/- 1% k/k has been established based on engineering judgment. A > 1% deviation
in reactivity from that predicted is larger than expected
for normal operation and should therefore be evaluated.
APPLICABILITY In MODE 1, most of the control rods are withdrawn and steady state operation is typically achieved. Under these
conditions, the comparison between predicted and monitored
core reactivity provides an effective measure of the
reactivity anomaly. In MODE 2, control rods are typically
being withdrawn during a startup. In MODES 3 and 4, all
control rods are fully inserted and therefore the reactor is
in the least reactive state, where monitoring core
reactivity is not necessary. In MODE 5, fuel loading
results in a continually changing core reactivity. SDM
requirements (LCO 3.1.1) ensure that fuel movements are
performed within the bounds of the safety analysis, and an
SDM demonstration is required during the first startup
following operations that could have altered core reactivity (e.g., fuel movement, control rod replacement, shuffling).
The SDM test, required by LCO 3.1.1, provides a direct
comparison of the predicted and monitored core reactivity at
cold conditions; therefore, Reactivity Anomalies is not
required during these conditions.
ACTIONS A.1 Should an anomaly develop between measured and predicted
core reactivity, the core reactivity difference must be
restored to within the limit to ensure continued operation
is within the core design assumptions. Restoration to
within the limit could be performed by an evaluation of the
core design and safety analysis to determine the reason for
the anomaly. This evaluation normally reviews the core
conditions to determine their consistency with input to
design calculations. Measured core and process parameters (continued)
Reactivity Anomalies B 3.1.2 Quad Cities 1 and 2 B 3.1.2-4 Revision 0 BASES ACTIONS A.1 (continued) are also normally evaluated to determine that they are
within the bounds of the safety analysis, and safety
analysis calculational models may be reviewed to verify that
they are adequate for representation of the core conditions.
The required Completion Time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> is based on the low
probability of a DBA occurring during this period, and
allows sufficient time to assess the physical condition of
the reactor and complete the evaluation of the core design
and safety analysis.
B.1 If the core reactivity cannot be restored to within the
1% k/k limit, the plant must be brought to a MODE in which the LCO does not apply. To achieve this status, the plant
must be brought to at least MODE 3 within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. The
allowed Completion Time of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> is reasonable, based on
operating experience, to reach MODE 3 from full power
conditions in an orderly manner and without challenging
plant systems.
SURVEILLANCE SR 3.1.2.1 REQUIREMENTS Verifying the reactivity difference between the monitored
and predicted core k eff is within the limits of the LCO provides added assurance that plant operation is maintained
within the assumptions of the DBA and transient analyses.
The Core Monitoring System calculates the core k eff for the reactor conditions obtained from plant instrumentation. A
comparison of the monitored core k eff to the predicted core k eff at the same cycle exposure is used to calculate the reactivity difference. The comparison is required when the
core reactivity has potentially changed by a significant
amount. This may occur following a refueling in which new
fuel assemblies are loaded, fuel assemblies are shuffled
within the core, or control rods are replaced or shuffled.
Control rod replacement refers to the decoupling and removal
of a control rod from a core location, and subsequent
replacement with a new control rod or a control rod from
another core location. Also, core reactivity changes during
the cycle. The 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> interval after reaching equilibrium (continued)
Reactivity Anomalies B 3.1.2 Quad Cities 1 and 2 B 3.1.2-5 Revision 0 BASES SURVEILLANCE SR 3.1.2.1 (continued)
REQUIREMENTS conditions following a startup is based on the need for
equilibrium xenon concentrations in the core, such that an
accurate comparison between the monitored and predicted core
k eff can be made. For the purposes of this SR, the reactor is assumed to be at equilibrium conditions when steady state
operations (no control rod movement or core flow changes) at 75% RTP have been obtained. The 1000 MWD/T Frequency was
developed, considering the relatively slow change in core
reactivity with exposure and operating experience related to
variations in core reactivity. This comparison requires the
core to be operating at power levels which minimize the
uncertainties and measurement errors, in order to obtain
meaningful results. Therefore, the comparison is only done
when in MODE 1. The core weight, tons(T) in MWD/T, reflects
metric tons.
REFERENCES 1. UFSAR, Sections 3.1.5.1, 3.1.5.5, and 3.1.5.6.
- 2. UFSAR, Chapter 15.
AC Sources-Shutdown B 3.8.2 Quad Cities 1 and 2 B 3.8.2-1 Revision 31 B 3.8 ELECTRICAL POWER SYSTEMS
B 3.8.2 AC Sources-Shutdown
BASES
BACKGROUND A description of the AC sources is provided in the Bases for LCO 3.8.1, "AC Sources-Operating."
Movement of a Spent Fuel Cask containing Spent Nuclear Fuel in a sealed Multi-Purpose Canister (MPC) and using a single
failure-proof crane is not considered to be "movement of
irradiated fuel assemblies in secondary containment" (Refs.
1 and 2).
APPLICABLE The OPERABILITY of the minimum AC sources during MODES 4 SAFETY ANALYSES and 5, and during movement of recently irradiated fuel assemblies in the secondary containment ensures that:
- a. The facility can be maintained in the shutdown or refueling condition for extended periods;
- b. Sufficient instrumentation and control capability is available for monitoring and maintaining the unit
status; and
- c. Adequate AC electrical power is provided to mitigate events postulated during shutdown, such as an
inadvertent draindown of the vessel or a fuel handling
accident involving handling recently irradiated fuel.
Due to radioactive decay, AC electrical power is only required to mitigate fuel handling accidents involving handling recently irradiated fuel (i.e., fuel that has occupied part of a critical reactor core within the previous 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />).
In general, when the unit is shutdown the Technical
Specifications requirements ensure that the unit has the
capability to mitigate the consequences of postulated
accidents. However, assuming a single failure and
concurrent loss of all offsite or loss of all onsite power
is not required. The rationale for this is based on the
fact that many Design Basis Accidents (DBAs) that are
analyzed in MODES 1, 2, and 3 have no specific analyses in
MODES 4 and 5. Worst case bounding events are deemed not
(continued)
AC Sources-Shutdown B 3.8.2 Quad Cities 1 and 2 B 3.8.2-2 Revision 31 BASES APPLICABLE credible in MODES 4 and 5 because the energy contained SAFETY ANALYSES within the reactor pressure boundary, reactor coolant (continued) temperature and pressure, and corresponding stresses result in the probabilities of occurrences significantly reduced or eliminated, and minimal consequences. These deviations from DBA analysis assumptions and design requirements during shutdown conditions are allowed by the LCO for required systems.
During MODES 1, 2, and 3, various deviations from the
analysis assumptions and design requirements are allowed
within the ACTIONS. This allowance is in recognition that certain testing and maintenance activities must be conducted, provided an acceptable level of risk is not exceeded. During MODES 4 and 5, performance of a significant number of required testing and maintenance activities is also
required. In MODES 4 and 5, the activities are generally
planned and administratively controlled. Relaxations from
typical MODES 1, 2, and 3 LCO requirements are acceptable
during shutdown MODES, based on:
- a. The fact that time in an outage is limited. This is a risk prudent goal as well as a utility economic
consideration.
- b. Requiring appropriate compensatory measures for certain conditions. These may include administrative controls, reliance on systems that do not necessarily meet typical
design requirements applied to systems credited in
operation MODE analyses, or both.
- c. Prudent utility consideration of the risk associated with multiple activities that could affect multiple
systems.
- d. Maintaining, to the extent practical, the ability to perform required functions (even if not meeting MODES 1, 2, and 3 OPERABILITY requirements) with systems assumed
to function during an event.
In the event of an accident during shutdown, this LCO ensures
the capability of supporting systems necessary for avoiding
immediate difficulty, assuming either a loss of all offsite
power or a loss of all onsite (diesel generator (DG)) power.
The AC sources satisfy Criterion 3 of 10 CFR 50.36(c)(2)(ii).
(continued)
AC Sources-Shutdown B 3.8.2 Quad Cities 1 and 2 B 3.8.2-3 Revision 31 BASES (continued)
LCO One offsite circuit supplying the onsite Class 1E power distribution subsystem(s) of LCO 3.8.8, "Distribution
Systems-Shutdown," ensures that all required loads are
powered from offsite power. An OPERABLE DG, associated with
a Distribution System Essential Service System (ESS) bus
required OPERABLE by LCO 3.8.8, ensures that a diverse power
source is available for providing electrical power support assuming a loss of the offsite circuit. Together, OPERABILITY of the required offsite circuit and DG ensures
the availability of sufficient AC sources to operate the
plant in a safe manner and to mitigate the consequences of
postulated events during shutdown (e.g., fuel handling
accidents involving handling recently irradiated fuel and reactor vessel draindown).
The qualified offsite circuit(s) must be capable of
maintaining rated frequency and voltage while connected to
their respective ESS bus(es), and of accepting required
loads during an accident. Qualified offsite circuits are
those that are described in the UFSAR and are part of the
licensing basis for the unit. The offsite circuit from the
345 kV switchyard consists of the incoming breakers and
disconnects to the 12 or 22 reserve auxiliary transformer (RAT), associated 12 or 22 RAT, and the respective circuit
path including feeder breakers to 4160 kV ESS buses required
by LCO 3.8.8. Another qualified circuit is provided by the
bus tie between the corresponding ESS buses of the two
units.
The required DG must be capable of starting, accelerating to
rated speed and voltage, connecting to its respective 4160 V
ESS bus on detection of bus undervoltage, and accepting
required loads. This sequence must be accomplished within
13 seconds. Each DG must also be capable of accepting
required loads within the assumed loading sequence
intervals, and must continue to operate until offsite power
can be restored to the 4160 V ESS buses. These capabilities
are required to be met from a variety of initial conditions
such as DG in standby with engine hot and DG in standby with
engine at ambient conditions. Additional DG capabilities
must be demonstrated to meet required Surveillances. Proper
sequencing of loads, including tripping of nonessential
loads, is a required function for DG OPERABILITY. The
necessary portions of the DG Cooling Water System capable of
providing cooling to the required DG is also required.
(continued)
AC Sources-Shutdown B 3.8.2 Quad Cities 1 and 2 B 3.8.2-4 Revision 31 BASES LCO It is acceptable for divisions to be cross tied during (continued) shutdown conditions, permitting a single offsite power circuit to supply all required divisions.
The AC sources are required to be OPERABLE in MODES 4 and 5 and during movement of recently irradiated fuel assemblies in the secondary containment to provide assurance that:
- a. Systems providing adequate coolant inventory makeup are available for the irradiated fuel assemblies in the core in case of an inadvertent draindown of the
reactor vessel;
- b. Systems needed to mitigate a fuel handling accident involving handling recently irradiated fuel (i.e., fuel that has occupied part of a critical reactor core within the previous 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />) are available;
- c. Systems necessary to mitigate the effects of events that can lead to core damage during shutdown are
available; and
- d. Instrumentation and control capability is available for monitoring and maintaining the unit in a cold
shutdown condition or refueling condition.
AC power requirements for MODES 1, 2, and 3 are covered in
ACTIONS LCO 3.0.3 is not applicable while in MODE 4 or 5. However, since recently irradiated fuel assembly movement can occur in MODE 1, 2, or 3, the ACTIONS have been modified by a Note
stating that LCO 3.0.3 is not applicable. If moving
recently irradiated fuel assemblies while in MODE 4 or 5, LCO 3.0.3 would not specify any action. If moving recently irradiated fuel assemblies while in MODE 1, 2, or 3, the
fuel movement is independent of reactor operations.
Entering LCO 3.0.3 while in MODE 1, 2, or 3 would require
the unit to be shutdown, but would not require immediate
suspension of movement of recently irradiated fuel assemblies. The Note to the ACTIONS, "LCO 3.0.3 is not
applicable," ensures that the actions for immediate
suspension of recently irradiated fuel assembly movement are not postponed due to entry into LCO 3.0.3.
A.1 An offsite circuit is considered inoperable if it is not (continued)
AC Sources-Shutdown B 3.8.2 Quad Cities 1 and 2 B 3.8.2-5 Revision 31 BASES ACTIONS A.1 (continued) available to one required ESS 4160 V ESS bus. If two or
more 4160 V ESS buses are required per LCO 3.8.8, one
division with offsite power available may be capable of
supporting sufficient required features to allow
continuation of CORE ALTERATIONS, recently irradiated fuel movement, and operations with a potential for draining the
reactor vessel. By the allowance of the option to declare
required features inoperable that are not powered from
offsite power, appropriate restrictions can be implemented
in accordance with the required feature(s) LCOs' ACTIONS.
Required features remaining powered from a qualified offsite
circuit, even if that circuit is considered inoperable
because it is not powering other required features, are not
declared inoperable by this Required Action. For example, if both Division 1 and 2 ESS buses are required OPERABLE by
LCO 3.8.8 and only the Division 1 ESS buses are not capable
of being powered from offsite power, then only the required
features powered from Division 1 ESS buses are required to
be declared inoperable.
A.2.1, A.2.2, A.2.3, A.2.4, B.1, B.2, B.3, and B.4
With the required offsite circuit not available to all
required divisions, the option still exists to declare all
required features inoperable per Required Action A.1. Since
this option may involve undesired administrative efforts, the allowance for sufficiently conservative actions is made.
With the required DG inoperable, the minimum required
diversity of AC power sources is not available. It is, therefore, required to suspend CORE ALTERATIONS, movement of
recently irradiated fuel assemblies in the secondary containment, and activities that could result in inadvertent
draining of the reactor vessel.
Suspension of these activities shall not preclude completion
of actions to establish a safe conservative condition.
These actions minimize the probability of the occurrence of
postulated events. It is further required to immediately
initiate action to restore the required AC sources and to
continue this action until restoration is accomplished in
order to provide the necessary AC power to the plant safety
systems. (continued)
AC Sources-Shutdown B 3.8.2 Quad Cities 1 and 2 B 3.8.2-6 Revision 31 BASES ACTIONS A.2.1, A.2.2, A.2.3, A.2.4, B.1, B.2, B.3, and B.4 (continued)
The Completion Time of immediately is consistent with the
required times for actions requiring prompt attention. The
restoration of the required AC electrical power sources
should be completed as quickly as possible in order to
minimize the time during which the plant safety systems may
be without sufficient power.
Pursuant to LCO 3.0.6, the Distribution System ACTIONS would
not be entered even if all AC sources to it are inoperable, resulting in de-energization. Therefore, the Required
Actions of Condition A have been modified by a Note to
indicate that when Condition A is entered with no AC power
to any required ESS bus, ACTIONS for LCO 3.8.8 must be
immediately entered. This Note allows Condition A to
provide requirements for the loss of the offsite circuit
whether or not a division is de-energized. LCO 3.8.8
provides the appropriate restrictions for the situation
involving a de-energized division.
SURVEILLANCE SR 3.8.2.1 REQUIREMENTS SR 3.8.2.1 requires the SRs from LCO 3.8.1 that are
necessary for ensuring the OPERABILITY of the AC sources in
other than MODES 1, 2, and 3 to be applicable. SR 3.8.1.9
is not required to be met since only one offsite circuit is
required to be OPERABLE. SR 3.8.1.20 is excepted because
starting independence is not required with the DG(s) that is
not required to be OPERABLE. SR 3.8.1.21 is not required to
be met because the opposite unit's DG is not required to be
OPERABLE in MODES 4 and 5, and during movement of recently irradiated fuel assemblies in secondary containment. Refer
to the corresponding Bases for LCO 3.8.1 for a discussion of
each SR.
This SR is modified by two Notes. The reason for Note 1 is
to preclude requiring the OPERABLE DG(s) from being
paralleled with the offsite power network or otherwise
rendered inoperable during the performance of SRs, and to
preclude de-energizing a required 4160 V ESS bus or
disconnecting a required offsite circuit during performance (continued)
AC Sources-Shutdown B 3.8.2 Quad Cities 1 and 2 B 3.8.2-7 Revision 29 BASES SURVEILLANCE SR 3.8.2.1 (continued)
REQUIREMENTS of SRs. With limited AC sources available, a single event
could compromise both the required circuit and the DG. It
is the intent that these SRs must still be capable of being
met, but actual performance is not required during periods
when the DG and offsite circuit are required to be OPERABLE.
Note 2 states that SRs 3.8.1.13 and 3.8.1.19 are not
required to be met when its associated ECCS subsystem(s) are
not required to be OPERABLE. These SRs demonstrate the DG
response to an ECCS initiation signal (either alone or in
conjunction with a loss of offsite power signal). This is
consistent with the ECCS instrumentation requirements that
do not require the ECCS initiation signals when the
associated ECCS subsystem is not required to be OPERABLE per
LCO 3.5.2, "ECCS-Shutdown."
REFERENCES 1. UFSAR, Section 9.1.4.3.2.
- 2. NRC Safety Evaluation Report for the Holtec International HI-STORM 100 Storage System (Docket Number 72-1014, Certificate Number 1014, Amendment 2).
DC Sources-Shutdown B 3.8.5 Quad Cities 1 and 2 B 3.8.5-1 Revision 31 B 3.8 ELECTRICAL POWER SYSTEMS
B 3.8.5 DC Sources-Shutdown
BASES
BACKGROUND A description of the DC sources is provided in the Bases for LCO 3.8.4, "DC Sources-Operating."
Movement of a Spent Fuel Cask containing Spent Nuclear Fuel in a sealed Multi-Purpose Canister (MPC) and using a single
failure-proof crane is not considered to be "movement of
irradiated fuel assemblies in secondary containment" (Refs.
3 and 4).
APPLICABLE The initial conditions of Design Basis Accident and SAFETY ANALYSES transient analyses in the UFSAR, Chapter 6 (Ref. 1) and Chapter 15 (Ref. 2), assume that Engineered Safety Feature
systems are OPERABLE. The DC electrical power system
provides normal and emergency DC electrical power for the
diesel generators (DGs), emergency auxiliaries, and control
and switching during all MODES of operation and during
movement of recently irradiated fuel assemblies in the secondary containment.
The OPERABILITY of the DC subsystems is consistent with the
initial assumptions of the accident analyses and the
requirements for the supported systems' OPERABILITY.
The OPERABILITY of the minimum DC electrical power sources
during MODES 4 and 5 and during movement of recently irradiated fuel assemblies in the secondary containment
ensures that:
- a. The facility can be maintained in the shutdown or refueling condition for extended periods;
- b. Sufficient instrumentation and control capability is available for monitoring and maintaining the unit
status; and
- c. Adequate DC electrical power is provided to mitigate events postulated during shutdown, such as an
inadvertent draindown of the vessel or a fuel handling
accident involving handling recently irradiated fuel.
Due to radioactive decay, DC electrical power is only (continued)
DC Sources-Shutdown B 3.8.5 Quad Cities 1 and 2 B 3.8.5-2 Revision 33 BASES
APPLICABLE required to mitigate fuel handling accidents involving SAFETY ANALYSES handling recently irradiated fuel (i.e., fuel that has (continued) occupied part of a critical reactor core within the previous 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />).
In general, when the unit is shut down, the Technical Specifications requirements ensure that the unit has the capability to mitigate the consequences of postulated accidents. However, assuming a single failure and
concurrent loss of all offsite or all onsite power is not
required. The rationale for this is based on the fact that many Design Basis Accidents (DBAs) that are analyzed in MODES 1, 2, and 3 have no specific analyses in MODES 4 and
- 5. Worst case bounding events are deemed not credible in MODES 4 and 5 because the energy contained within the
reactor pressure boundary, reactor coolant temperature and
pressure, and the corresponding stresses result in the
probabilities of occurrence being significantly reduced or
eliminated, and in minimal consequences. These deviations
from DBA analysis assumptions and design requirements during
shutdown conditions are allowed by the LCO for required
systems. The shutdown Technical Specification requirements are
designed to ensure that the unit has the capability to
mitigate the consequences of certain postulated accidents.
Worst case Design Basis Accidents which are analyzed for
operating MODES are generally viewed not to be a significant
concern during shutdown MODES due to the lower energies
involved. The Technical Specifications therefore require a
lesser complement of electrical equipment to be available
during shutdown than is required during operating MODES.
More recent work completed on the potential risks associated
with shutdown, however, have found significant risk
associated with certain shutdown evolutions. As a result, in addition to the requirements established in the Technical
Specifications, the industry has adopted NUMARC 91-06, "Guidelines for Industry Actions to Assess Shutdown
Management," as an industry initiative to manage shutdown
tasks and associated electrical support to maintain risk at
an acceptable low level. This may require the availability
of additional equipment beyond that required by the shutdown
Technical Specifications.
The DC sources satisfy Criterion 3 of
(continued)
DC Sources-Shutdown B 3.8.5 Quad Cities 1 and 2 B 3.8.5-3 Revision 33 BASES LCO The DC electrical power subsystems - with: a) the required 250 VDC subsystem consisting of one 250 VDC battery, one battery charger, and the corresponding control equipment and
interconnecting cabling supplying power to the associated bus; and b) the required 125 VDC subsystem consisting of one battery, one battery charger, and the corresponding control equipment and interconnecting cabling supplying power to the associated bus - are required to be OPERABLE to support some of the required DC distribution subsystems required OPERABLE by LCO 3.8.8, "Distribution Systems-Shutdown." This
requirement ensures the availability of sufficient DC
electrical power sources to operate the unit in a safe
manner and to mitigate the consequences of postulated events
during shutdown (e.g., fuel handling accidents involving
handling recently irradiated fuel and inadvertent reactor
vessel draindown). The associated alternate 125 VDC
electrical power subsystem may be used to satisfy the
requirements of the 125 VDC subsystem.
APPLICABILITY The DC electrical power sources required to be OPERABLE in MODES 4 and 5 and during movement of recently irradiated
fuel assemblies in the secondary containment provide
assurance that:
- a. Required features to provide adequate coolant inventory makeup are available for the irradiated fuel
assemblies in the core in case of an inadvertent
draindown of the reactor vessel;
- b. Required features needed to mitigate a fuel handling accident involving handling recently irradiated fuel
are available;
- c. Required features necessary to mitigate the effects of events that can lead to core damage during shutdown
are available; and
- d. Instrumentation and control capability is available for monitoring and maintaining the unit in a cold
shutdown condition or refueling condition.
Due to radioactive decay, DC electrical power is only
required to mitigate fuel handling accidents involving
handling recently irradiated fuel (i.e., fuel that has
occupied part of a critical reactor core within the previous
24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />).
(continued)
DC Sources-Shutdown B 3.8.5 Quad Cities 1 and 2 B 3.8.5-4 Revision 33 BASES APPLICABILITY The DC electrical power requirements for MODES 1, 2, and 3 (continued) are covered in LCO 3.8.4.
ACTIONS LCO 3.0.3 is not applicable while in MODE 4 or 5. However, since recently irradiated fuel assembly movement can occur
in MODE 1, 2, or 3, the ACTIONS have been modified by a Note
stating that LCO 3.0.3 is not applicable. If moving
recently irradiated fuel assemblies while in MODE 4 or 5, LCO 3.0.3 would not specify any action. If moving recently
irradiated fuel assemblies while in MODE 1, 2, or 3, the
fuel movement is independent of reactor operations.
Entering LCO 3.0.3 while in MODE 1, 2, or 3 would require
the unit to be shutdown, but would not require immediate
suspension of movement of recently irradiated fuel
assemblies. The Note to the ACTIONS, "LCO 3.0.3 is not
applicable," ensures that the actions for immediate
suspension of recently irradiated fuel assembly movement are
not postponed due to entry into LCO 3.0.3.
A.1, A.2.1, A.2.2, A.2.3, and A.2.4
By allowance of the option to declare required features
inoperable with associated DC electrical power subsystem(s)
inoperable, appropriate restrictions are implemented in
accordance with the affected system LCOs' ACTIONS. However, in many instances, this option may involve undesired
administrative efforts. Therefore, the allowance for
sufficiently conservative actions is made (i.e., to suspend
CORE ALTERATIONS, movement of recently irradiated fuel
assemblies in the secondary containment, and any activities
that could result in inadvertent draining of the reactor
vessel).
Suspension of these activities shall not preclude completion
of actions to establish a safe conservative condition.
These actions minimize the probability of the occurrence of
postulated events. It is further required to immediately
initiate action to restore the required DC electrical power
subsystems and to continue this action until restoration is
accomplished in order to provide the necessary DC electrical
power to the plant safety systems.
The Completion Time of immediately is consistent with the
required times for actions requiring prompt attention. The
(continued)
DC Sources-Shutdown B 3.8.5 Quad Cities 1 and 2 B 3.8.5-5 Revision 33 BASES ACTIONS A.1, A.2.1, A.2.2, A.2.3, and A.2.4 (continued)
restoration of the required DC electrical power subsystems
should be completed as quickly as possible in order to
minimize the time during which the plant safety systems may
be without sufficient power.
SURVEILLANCE SR 3.8.5.1 REQUIREMENTS SR 3.8.5.1 requires all Surveillances required by SR 3.8.4.1
through SR 3.8.4.8 to be applicable. Therefore, see the
corresponding Bases for LCO 3.8.4 for a discussion of each
SR. This SR is modified by a Note. The reason for the Note is
to preclude requiring the OPERABLE 250 VDC source from being
discharged below their capability to provide the required
power supply or otherwise rendered inoperable during the
performance of SRs. It is the intent that these SRs must
still be capable of being met, but actual performance is not
required.
REFERENCES 1. UFSAR, Chapter 6.
- 2. UFSAR, Chapter 15.
- 3. UFSAR, Section 9.1.4.3.2.
- 4. NRC Safety Evaluation Report for the Holtec International HI-STORM 100 Storage System (Docket
Number 72-1014, Certificate Number 1014, Amendment 2).
Control Rod Position Indication B 3.9.4 Quad Cities 1 and 2 B 3.9.4-1 Revision 0 B 3.9 REFUELING OPERATIONS
B 3.9.4 Control Rod Position Indication
BASES
BACKGROUND The full-in position indication channel for each control rod provides necessary information to the refueling interlocks
to prevent inadvertent criticalities during refueling
operations. During refueling, the refueling interlocks (LCO 3.9.1, "Refueling Equipment Interlocks," and LCO 3.9.2, "Refuel Position One-Rod-Out Interlock") use the full-in
position indication channel to limit the operation of the
refueling equipment and the movement of the control rods.
Two full-in position indication switches (S51 and S52)
provide input to the all-rods-in logic for each control rod.
Switch S51 provides full core display beyond full-in (scram)
position indication (double dashes - no number) and switch
S52 provides full core display normal green full-in position
indication. Switch S52 is set slightly beyond switch S00, which provides the digital "00" full-in position readout (switch S00 does not provide input to the all-rods-in logic
and is not considered a full-in channel). When switch S52
is actuated, the color of the full core display "00" readout
is changed from amber to green, indicating the control rod
is full-in and latched. Switches S51 and S52 are wired in
parallel, such that, if either switch indicates full-in, the
all-rods-in logic will receive a full-in signal for that
control rod. Therefore, each control rod is considered to
have only one "full-in" position indication channel. The
absence of the full-in position indication channel signal
for any control rod removes the all-rods-in permissive for
the refueling equipment interlocks and prevents fuel
loading. Also, this condition causes the refuel position
one-rod-out interlock to not allow the selection of any
other control rod. The all-rods-in logic provides two
signals, one to each of the two Reactor Manual Control
System rod block circuits.
UFSAR, Sections 3.1.5.3 and 3.1.5.4, requires that one of
the two required independent reactivity control systems be
capable of holding the reactor core subcritical under cold
conditions (Ref. 1). The control rods serve as the system
capable of maintaining the reactor subcritical in cold
conditions.
(continued)
Control Rod Position Indication B 3.9.4 Quad Cities 1 and 2 B 3.9.4-2 Revision 0 BASES (continued)
APPLICABLE Prevention and mitigation of prompt reactivity excursions SAFETY ANALYSES during refueling are provided by the refueling interlocks (LCO 3.9.1 and LCO 3.9.2), the SDM (LCO 3.1.1, "SHUTDOWN
MARGIN (SDM)"), the intermediate range monitor neutron flux
scram (LCO 3.3.1.1, "Reactor Protection System (RPS)
Instrumentation"), and the control rod block instrumentation (LCO 3.3.2.1, "Control Rod Block Instrumentation").
The safety analysis for the control rod removal error during
refueling (Ref. 2) assumes the functioning of the refueling
interlocks and adequate SDM. The full-in position
indication channel is required to be OPERABLE so that the
refueling interlocks can ensure that fuel cannot be loaded
with any control rod withdrawn and that no more than one
control rod can be withdrawn at a time.
Control rod position indication satisfies Criterion 3 of
LCO The control rod full-in position indication channel for each control rod must be OPERABLE to provide the required input
to the refueling interlocks. A channel is OPERABLE if it
provides correct position indication to the refueling
equipment interlock all-rods-in logic (LCO 3.9.1) and the
refuel position one-rod-out interlock logic (LCO 3.9.2).
APPLICABILITY During MODE 5, the control rods must have OPERABLE full-in position indication channels to ensure the applicable
refueling interlocks will be OPERABLE.
In MODES 1 and 2, requirements for control rod position are
specified in LCO 3.1.3, "Control Rod OPERABILITY." In
MODES 3 and 4, with the reactor mode switch in the shutdown
position, a control rod block (LCO 3.3.2.1) ensures all
control rods are inserted, thereby preventing criticality
during shutdown conditions.
ACTIONS A Note has been provided to modify the ACTIONS related to control rod position indication channels. Section 1.3, Completion Times, specifies that once a Condition has been (continued)
Control Rod Position Indication B 3.9.4 Quad Cities 1 and 2 B 3.9.4-3 Revision 0 BASES ACTIONS entered, subsequent divisions, subsystems, components, or (continued) variables expressed in the Condition, discovered to be inoperable or not within limits, will not result in separate
entry into the Condition. Section 1.3 also specifies that
Required Actions of the Condition continue to apply for each
additional failure, with Completion Times based on initial
entry into the Condition. However, the Required Actions for
inoperable control rod position indication channels provide
appropriate compensatory measures for separate inoperable
channels. As such, this Note has been provided, which
allows separate Condition entry for each inoperable control
rod position indication channel.
A.1.1, A.1.2, A.1.3, A.2.1 and A.2.2
With one or more full-in position indication channels
inoperable, compensating actions must be taken to protect
against potential reactivity excursions from fuel assembly
insertions or control rod withdrawals. This may be
accomplished by immediately suspending in-vessel fuel
movement and control rod withdrawal, and immediately
initiating action to fully insert all insertable control
rods in core cells containing one or more fuel assemblies.
Actions must continue until all insertable control rods in
core cells containing one or more fuel assemblies are fully
inserted. Control rods in core cells containing no fuel
assemblies do not affect the reactivity of the core and, therefore, do not have to be inserted. Suspension of
in-vessel fuel movements and control rod withdrawal shall
not preclude moving a component to a safe position.
Alternatively, actions must be immediately initiated to
fully insert the control rod(s) associated with the
inoperable full-in position indicator(s) and disarm (electrically or hydraulically) the drive(s) to ensure that
the control rod is not withdrawn. A control rod can be
hydraulically disarmed by closing the drive water and
exhaust water isolation valves. A control rod can be
electrically disarmed by disconnecting power from all four
directional control valve solenoids. Actions must continue
until all associated control rods are fully inserted and
drives are disarmed. Under these conditions (control rod
fully inserted and disarmed), an inoperable full-in channel
(continued)
Control Rod Position Indication B 3.9.4 Quad Cities 1 and 2 B 3.9.4-4 Revision 0 BASES ACTIONS A.1.1, A.1.2, A.1.3, A.2.1 and A.2.2 (continued) may be bypassed to allow refueling operations to proceed.
An alternate method must be used to ensure the control rod
is fully inserted (e.g., use the "00" notch position
indication).
SURVEILLANCE SR 3.9.4.1 REQUIREMENTS The full-in position indication channels provide input to
the one-rod-out interlock and other refueling interlocks
that require an all-rods-in permissive. The interlocks are
actuated when the full-in position indication for any
control rod is not present, since this indicates that all
rods are not fully inserted. Therefore, testing of the
full-in position indication channels is performed to ensure
that when a control rod is withdrawn, the full-in position
indication is not present. The full-in position indication
channel is considered inoperable even with the control rod
fully inserted, if it would continue to indicate full-in
with the control rod withdrawn. Performing the SR each time
a control rod is withdrawn from the full-in position is
considered adequate because of the procedural controls on
control rod withdrawals and the visual indications available
in the control room to alert the operator to control rods
not fully inserted.
REFERENCES 1. UFSAR, Sections 3.1.5.3 and 3.1.5.4.
- 2. UFSAR, Section 15.4.1.
Control Rod Testing-Operating B 3.10.6 Quad Cities 1 and 2 B 3.10.6-1 Revision 0 B 3.10 SPECIAL OPERATIONS
B 3.10.6 Control Rod Testing-Operating
BASES BACKGROUND The purpose of this Special Operations LCO is to permit control rod testing, while in MODES 1 and 2, by imposing certain administrative controls. Control rod patterns
during startup conditions are controlled by the operator and
the rod worth minimizer (RWM) (LCO 3.3.2.1, "Control Rod
Block Instrumentation"), such that only the specified
control rod sequences and relative positions required by
LCO 3.1.6, "Rod Pattern Control," are allowed over the
operating range from all control rods inserted to the low
power setpoint (LPSP) of the RWM. The sequences effectively
limit the potential amount and rate of reactivity increase
that could occur during a control rod drop accident (CRDA).
During these conditions, control rod testing is sometimes
required that may result in control rod patterns not in
compliance with the prescribed sequences of LCO 3.1.6.
These tests include SDM demonstrations, control rod scram
time testing, and control rod friction testing. This
Special Operations LCO provides the necessary exemption to
the requirements of LCO 3.1.6 and provides additional
administrative controls to allow the deviations in such
tests from the prescribed sequences in LCO 3.1.6.
APPLICABLE The analytical methods and assumptions used in evaluating SAFETY ANALYSES the CRDA are summarized in References 1, 2, 3, 4, and 5.
CRDA analyses assume the reactor operator follows prescribed
withdrawal sequences. These sequences define the potential
initial conditions for the CRDA analyses. The RWM provides
backup to operator control of the withdrawal sequences to
ensure the initial conditions of the CRDA analyses are not
violated. For special sequences developed for control rod
testing, the initial control rod patterns assumed in the
safety analysis of References 1, 2, 3, 4, and 5 may not be
preserved. Therefore special CRDA analyses are required to
demonstrate that these special sequences will not result in
unacceptable consequences, should a CRDA occur during the
testing. These analyses, performed in accordance with an
NRC approved methodology, are dependent on the specific test
being performed.
(continued)
Control Rod Testing-Operating B 3.10.6 Quad Cities 1 and 2 B 3.10.6-2 Revision 0 BASES APPLICABLE As described in LCO 3.0.7, compliance with Special SAFETY ANALYSES Operations LCOs is optional, and therefore, no criteria of (continued) 10 CFR 50.36(c)(2)(ii) apply. Special Operations LCOs provide flexibility to perform certain operations by
appropriately modifying requirements of other LCOs. A
discussion of the criteria satisfied for the other LCOs is
provided in their respective Bases.
LCO As described in LCO 3.0.7, compliance with this Special Operations LCO is optional. Control rod testing may be performed in compliance with the prescribed sequences of
LCO 3.1.6, and during these tests, no exceptions to the
requirements of LCO 3.1.6 are necessary. For testing
performed with a sequence not in compliance with LCO 3.1.6, the requirements of LCO 3.1.6 may be suspended, provided
additional administrative controls are placed on the test to
ensure that the assumptions of the special safety analysis
for the test sequence are satisfied. Assurances that the
test sequence is followed can be provided by either
programming the test sequence into the RWM, with conformance
verified as specified in SR 3.3.2.1.8 and allowing the RWM
to monitor control rod withdrawal and provide appropriate
control rod blocks if necessary, or by verifying conformance
to the approved test sequence by a second licensed operator (Reactor Operator or Senior Reactor Operator) or other task
qualified member of the technical staff (e.g., shift
technical advisor or reactor engineer). These controls are
consistent with those normally applied to operation in the
startup range as defined in the SRs and ACTIONS of
LCO 3.3.2.1, "Control Rod Block Instrumentation." APPLICABILITY Control rod testing, while in MODES 1 and 2, with THERMAL POWER greater than 10% RTP, is adequately controlled by the existing LCOs on power distribution limits and control rod
block instrumentation. Control rod movement during these
conditions is not restricted to prescribed sequences and can
be performed within the constraints of LCO 3.2.1, "AVERAGE
PLANAR LINEAR HEAT GENERATION RATE (APLHGR)," LCO 3.2.2, "MINIMUM CRITICAL POWER RATIO (MCPR)," LCO 3.2.3, "LINEAR
HEAT GENERATION RATE (LHGR)," and LCO 3.3.2.1. With THERMAL
POWER less than or equal to 10% RTP, the provisions of this (continued)
Control Rod Testing-Operating B 3.10.6 Quad Cities 1 and 2 B 3.10.6-3 Revision 0 BASES APPLICABILITY Special Operations LCO are necessary to perform special (continued) tests that are not in conformance with the prescribed sequences of LCO 3.1.6.
While in MODES 3 and 4, control rod withdrawal is only
allowed if performed in accordance with Special Operations
LCO 3.10.2, "Single Control Rod Withdrawal-Hot Shutdown,"
or Special Operations LCO 3.10.3, "Single Control Rod
Withdrawal-Cold Shutdown," which provide adequate controls
to ensure that the assumptions of the safety analysis of
References 1, 2, 3, 4, and 5 are satisfied. During these
Special Operations and while in MODE 5, the one-rod-out
interlock (LCO 3.9.2, "Refuel Position One-Rod-Out
Interlock,") and scram functions (LCO 3.3.1.1, "Reactor
Protection System (RPS) Instrumentation," and LCO 3.9.5, "Control Rod OPERABILITY-Refueling"), or the added
administrative controls prescribed in the applicable Special
Operations LCOs, provide mitigation of potential reactivity
excursions.
ACTIONS A.1 With the requirements of the LCO not met (e.g., the control rod pattern is not in compliance with the special test
sequence, the sequence is improperly loaded in the RWM) the
testing is required to be immediately suspended. Upon
suspension of the special test, the provisions of LCO 3.1.6
are no longer excepted, and appropriate actions are to be
taken to restore the control rod sequence to the prescribed
sequence of LCO 3.1.6, or to shut down the reactor, if
required by LCO 3.1.6.
SURVEILLANCE SR 3.10.6.1 REQUIREMENTS With the special test sequence not programmed into the RWM, a second licensed operator (Reactor Operator or Senior
Reactor Operator) or other task qualified member of the
technical staff (e.g., shift technical advisor or reactor
engineer) is required to verify conformance with the
approved sequence for the test. This verification must be
performed during control rod movement to prevent deviations
from the specified sequence. A Note is added to indicate
that this Surveillance does not need to be met if
SR 3.10.6.2 is satisfied.
(continued)
Control Rod Testing-Operating B 3.10.6 Quad Cities 1 and 2 B 3.10.6-4 Revision 0 BASES SURVEILLANCE SR 3.10.6.2 REQUIREMENTS (continued) When the RWM provides conformance to the special test sequence, the test sequence must be verified to be correctly
loaded into the RWM prior to control rod movement. This
Surveillance demonstrates compliance with SR 3.3.2.1.8, thereby demonstrating that the RWM is OPERABLE. A Note has
been added to indicate that this Surveillance does not need
to be met if SR 3.10.6.1 is satisfied.
REFERENCES 1. UFSAR, Section 15.4.10.
- 2. XN-NF-80-19(P)(A), Volume 1, Supplement 2, Section 7.1, Exxon Nuclear Methodology for Boiling Water
Reactor Neutronics Methods for Design Analysis, (as
specified in Technical Specification 5.6.5).
- 3. NEDE-24011-P-A-US, General Electric Standard Application for Reactor Fuel, (as specified in
Technical Specification 5.6.5).
- 4. Letter from T. Pickens (BWROG) to G.C. Lainas (NRC) "Amendment 17 to General Electric Licensing Topical
Report NEDE-24011-P-A," BWROG-8644, August 15, 1986.
- 5. NFSR-0091, Benchmark of CASMO/MICROBURN BWR Nuclear Design Methods, Commonwealth Edison Topical Report, (as specified in Technical Specification 5.6.5).