ML20076E435
| ML20076E435 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 08/13/1991 |
| From: | Shankman S Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20076E437 | List: |
| References | |
| NUDOCS 9108200105 | |
| Download: ML20076E435 (17) | |
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f4-o'T UNITED STATES S M).gdl i NUCLEAR REGULATORY COMMISSION 7 l b,
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WASHINoTON D.C. 20555 gv y PupljC,pERVICECOMPAllYOFNEWHAMPSHIRE,ETAL.*
DOCKET tl0. 50,44) 5.Epp,Rpp,K,,5,TMJpN UNIT N0. 1 1
AMEtlDMENT T0_ F,A,ClljT,Y,pFERA,TjN),LJCENpE R
Amendment No. 5 License No. NPF-86 1.
The Nuclear Regulatory Commission (the Commission or the NRC) has found that:
A.
The application for amendment filed by the Public Service Company of New Hampshire (the licensee), acting for itself and as agent and representative o' the 11 other utilities listed below and i
hereafter referred to as licensees, dated December 14, 1990 as supplemented by letters dated April 24, 1991, June 14, 1991, and July 15, 1991, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's rules and regulations set forth in 10 CFR Chapter I; B.
The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Conunission; C.
There is reasonable assurance: (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Con: mission's regulations set forth in 10 CFR Chapter I; D.
The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E.
The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied.
- Public Sirvice Company of flew Hampshire is authorized to act as agent for:
Canal Electric Company, The Connecticut Light and Power Company, EUA Power Corporation, Hudson Light & Power Department, Massachusetts Municipal Wholesale Electric Company, Montaup Electric Company, tiew England Power Company, New Hampshire Electric Cooperative, Inc., Taunton Municipal Light Plant, The United Illuminating Company, and Vermont Electric Generation and Transmission Cooperative, Inc., and has exclusive responsibility and control over the physical construction, operation and maintenance of the facility.
9108200105 910813 PDR ADOCK 05000443 P
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Accordingly, the license is amended by -changes to the Technical Specifications as indicated in the attachment to this license amendesnt, and-paragraph ?.C.(?) of_ Facility Operating License No, iPF-86 is hereby amended to read as follows:
(?)
T,echn_ica,1_ Syecifica tions a
e The Technical Specifications contained in Appendix A, as revised through Amendment No. 5, and the Environmental Protection Plan contained in Appendix C are incorporated into facility Licente No.
PSNH shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
3.
This license amendment is effective as of its date of issuance and shall be implemented prior to restart from the first refueling outage.
FOR THE NUCLEAR REGULATORY COMfilSSION IA Susan Shantman, Acting Director Project Directorate 1-3 Division of Reactor Projects - 1/11 Office of Nuclear Reactor Regulation
Attachment:
Changes:to the Technical Specifications Date of Issuance:
August 13, 1991-
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FACILITV'0PERATING LICENSE NO. NPF.86 i
DOCKET-NO. 50-443-s Replace the following pages of the Appendix A Technical Specifications with the attached pages. The revised pages are identified by Amendment number and contain vertical lines indicating the area of change. Overlap pages are provided for continuity.
Remove Insert l
3/4 4-34 3/4 4-34 3/4 4-34a*
y 3/4 4-35 3/4 4-35 r
3/4 5-10 3/4 5-10 B 3/4 4-16 B 3/4 4-16 l
B 3/4 4-17 B 3/4 4-17 j
B 3/4 5-2 B 3/4 5-2 i
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[R,E_SSURE/TEMPERATURELIMITS PRESSURIZER LIMITING CONDITION FOR OPERATION 3.4.9.2 The pressurizer temperature shall be limited to:
a.
A maximum heatup of 100'F in any 1-hour period, b.
A maximum cooldown of 200*F in any 1-hour period, and c.
A maximum spray water temperature differential of 320*F.
APPLICABILITY:
At all times.
ACTION:
With the pressurizer temperature limits in excess of any of the above limits, restore the temperature to within the limits within 30 minutes; perform an engineering evaluation to determine the effects of the out-of-iinit condition on the structural integrity of the pressurize ** determine that the pressurizer remains acceptable for continued operation or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and reduce the pressurizer pressure to less that 500 psig within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
SURVEILLANCE REQUIREMENTS 4.4.9.2 The pressurizer temperatures shall be determined to be within the limits at least once per 30 minutes during system heatup or cooldown.
The spray water temperature differential shall be determined to be within the limit at least once per 12. hours during auxiliary spray operation.
SEABROOK -- UNIT 1 3/4 4-33
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REACTOR COOLANT SYSTEM PRESSURE / TEMPERATURE LIMITS-OVERPRESSURE PROTECTION SYSTEMS LIMITING CONDITION FOR OPERATION 3.4.9.3 The following Overpressure Protection Systems shall be OPERABLE:
a.'
In MODE 4 when the temperature of any RCS cold leg is less than or equal to 329 F; and in MODE 5 and MODE 6 with all Safety Injection pumps inoperable:
1)
Two residual heat removal (RHR) suction relief valves each with a setpoint of 450 psig +0, -3 %; or 2)
Two power-operated relief valves (PORVs) with lift setpoints that vary with RCS temperature which do not exceed the limit established in Figure 3.4-4, or 3)
The Reactor Coolant System (RCS) depressurized with.an RCS vent aret. of greater than or equal to 1.58 square inches.
b.
In MODE 5 and MODE 6 with all Safety Injection pumps except one inoperable:
1)
The Reactor Coolant System (RCS) depressurized with an RCS vent area equal to or greater than 18 square inches.
APPLICABILITY:
MODE 4 when the temperature of any RCS cold leg is less than-or equal to 329 F; MODE 5 and MODE 6 with the reactor vessel head on.
ACTION:
a.
In MODE 4, MODE 5 and MODE 6 with all Safety Injection pumps inoperable:
1)
With one PORV and one RHR suction relief valve inoperable, I
either restore two PORVs or two RHR suction relief valves to OPERABLE status within 7 days-or depressurize and vent the RCS through at least a 1.58-square-inch vent within the next 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.
2)
With both PORVs and both RHR suction relief valves inoperable, I
depressurize and vent the RCS through at least a 1.58-square-inch vent within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.
3)
In the event the PORVs, or the RHR suction relief valves, or I
the RCS vent (s) are used to mitigate an RCS pressure transient, a Special Report shall be prepared and submitted to the Commis-sion pursuant to Specification 6.8.2 within 30 days.
The report-l shall describe the circumstances initiating the transient, the l
effect of the PORVs, or the RHR suction relief valves, or RCS vent (s) on the transient, and any corrective action necessary to prevent recurrence.
SEABROOK - UNIT 1 3/4 4-34 Amendment No. 3, 5,
REACTOR COOLANT SYSTEM PRESSURE / TEMPERATURE LIMITS OVERPRESSURE PROTECTION SYSTEMS LIMITING CONDITION FOR OPERATION ACTION:
(Continued) b.
In MODE S and MODE 6 with all Safety Injection pumps except one inoperable:
1)
With the RCS vent area less than 18 square inches, immediately restore all Safety Injection pumps to inoperable status.
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SEABROOK - UNIT 1 3/4 4-34a Amendment No. 5 l-
-REACTOR COOLANT SYSTEM
-PRESSURE / TEMPERATURE LIMITS
-0VERPRESSURE PROTECTION SYSTEMS SURVEILLANCE REQUIREMENTS 4.4.9.3.1 Each PORV shall be demonstrated OPERABLE by:
a.
Performance of an ANALOG CHANNEL OPERATIONAL TEST on the PORV actuation channel, but excluding valve operation, within 31 days prior to entering a condition in which the PORV is required OPERABLE and at least once per 31 days thereafter when the PORV is required OPERABLE; b.
Performance of a CHANNEL CALIBRATION on the PORV actuation channel at_least once per 18 months; and c.
Verifying:the PORV isolation valve is open at least once per 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> when the PORV is being used for overpressure protection.
-4,4.9.3.2 Each RHR suction relief valve shall be demonstrated OPERABLE when the RHR suction relief valves are being used for cold overpressure protection as follows:
For RHR suction relief valve RC-V89 by verifying at least once per' a.
- 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> that RHR suction isolation valves RC-V87 and RC-V88 are open.
b.
For-RHR suction relief valve RC-V24 by verifying at least once per 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> that RHR suction isolation valves RC-V22 and RC-V23 are open.
-c.
Testing pursuant to Specification 4.0.5.
4.4.9.3.3 The RCS vent (s) shall be verified to be open at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />
- when the vent (s) is being used for o'erpressure protection.
- Except when the vent pathway is provided with a valve (s) or devices (s) that is locked, sealed, or otherwise secured in the open position, then verify this valve (s) or device (s) open at least once per 31 days.
SEABROOK - UNIT 1 3/4 4-35 Amendment No. 3, 5, l
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(olsd) 1N10d13S AMOd nnnlXVM SEABROOK - UNIT 1 3/4 4-36
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l EMERGENCY TORC COOLING SYSTEMS ECCS SUS $YSTEMS - T,yg LESS THAN 350'F SURVEILLANCE REQUIREMENis f
4.5.3.1 1 The ECCS subsystem shall be demonstrated OPERABLE per the applicable requirements of Specification 4.5.2.
4.5.3.1.2 All centrifugal charging pumps and Safety injection pumps, except the above allowed OPERABLE pump 6, shall be demonstrkted inoperable
- by verifying that the motor circuit breakers are secured in the open position within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> af ter entering MODE 4 from MODE 3 or prior to the temperature of one or more of th6 RCS cold legs decreading below 325'F, whichever comes first, and at least 1
once per 31 days thereafter.
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' An inoperable pump may be energized for testing or for filling accumulators provided the discharge at the pump has been isolated from the RCS by a closed L
isolation valve with power removed from the valve operator, or by a manual j
isolation valve secured in the closed position.
I SEABROOK - UNIT 1 3/4 5-9
/
.t EMERGENCY CORE COOLING SYSTEMS ECCS SUBSYSTEMS
.,yg EQUAL TO OR LESS THAN 200 F LIMITING CONDITION FOR OPERATION 3.5.3.2 As a minimum, the following number of Safety Injection pumps shall be inoperable:
a.
Two when the RCS vent area is less than 18 square inches.*
b.
One when the RCS vent area is equal to or greater than 18 square inches.
t APPLICABILITY:
MODE 5 and MODE 6 with the reactor vessel head on.
I ACTION:
With fewer than the required number of Safety Injection pumps inoperable, 3
restore all pumps required to be inoperable, to inoperable status within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.
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SURVElliANCE REQUIREMENTS
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4.5.3.2 All Safety Injection pumps required to be inoperable shall be demon-strated inoperablo by verifying that the motor circuit breakers are secured in the open position at least once per 31 days.
- An inoperable pump may be energi ed for testing or for filling accumulators provided the discharge at the pui.ip has been isolated from the RCS by a closed isolation valve with power removed from the valve operator, or by a manual isolatico valve secured in the closed position.
l SEABROOK - UNIT 1 3/4 5-10 Amendment No. 5,
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REACTOR COOLANT SYSTEM BASES 3/4.4.9 PRESSURE / TEMPERATURE LIMITS (Continued)
COLO OVERPRESSURE PROTECTION The OPERABILITY of two PORVs or two RHR suctirn relief valves, or an RCS vent 6pening of at least 1.58 square inches ensures that the RCS wili be protected frpm pressure transients which could exceti the limits of Appenix G to 10 CFR Part 50 when one or more of the RCS cold l es are less than or equal to 329'F.
Either PORV or either RHR suction relief va,ve has adequate relieving capability te protect the RCS from overpressur4 ation when the 2
transient is limited to either:
(1) the start of an idle RCP with the secondary water temperature of the steam generator less tian or equal to 50'F above the RCS cold leg temperatures, or (2) the start of a centrifugal charging pump and its injection into a water-solid RCS.
The Haximum Alloweo PORV Setpoint for the Cold Overpressure Hitigation System (C(445) is derived by analysis which models the performance of the COMS assuming various mass input and heat input transients.
Operation with a PORV Setpoint less than or equal to the maximum Setpoint ensures that Appendix G criteria will not be violated with consideration for:
(1) a maximum pres-sure overshoot beyond the PORV Setpoint which can occur as a result of time de-lays in signal processing and valve opening; (2) a 50'F heat transport effect made possible by the geometrical relationship of the RHR suction line and the RCS wide range temperature indicator used for COMS; (3) instrument uncertain-ties; and (4) single failure.
To ensure mass and heat input transients more severe than those assumed cannot occur, Technical Specifications require lock-out of both Safety Injection pumps and all but one centrifugal charging pump while in H0 DES 4, 5, and 6 with the reactor vessel head installed and d hallow start of an RCP if secondary coolant temperature is more thca 50'F above reac-tor coolant temperature.
Exceptions to these requirements are acceptable as described below.
Operation above 350'F but less than 375'F with only centrifugal charging pump OPERABLE and no Safety Injection pumps OPERABLE is allowed for up to As shown by analysis, LOCAs occurring at low temperature, low pres-4 hours.
sure conditions can be successfully mitigated by the operation of a single centrifugal chstging pump and a single RHR pump with no credit for accumulator injection.
Given the short time duration and the condition of having only one centrifugal cha','ging pump OPERABLE and the probability of a LOCA occurring dur-ing this time, the failure of the single centrifugal charging pump is not assumed.
Op.eration below 350'F but greater than 325'F with all centrifugal charging During low andSafetyInjectionpumpsOPERABLEisallowedforupto4 hours.
pressure, low temperature operation all automatic Safety Injection actuation signals except Containment Pressure - High are blocked.
In normal conditions, a single failure of the ESF actuation circuitry will result in the starting of l
atmostonetrainofSafetyInjection(onecentrifugalchargingpump,andone For temperatures above 325 F, an overpressure event SafetyInjectionpump).
occurring as a result of starting two pumps can be successfully mitigated by Nbnt N. 3
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f REACTOR COOLANT SYSTEM BASES j
3/4.4.9 PRESSURE / TEMPERATURE LIMITS (Continued)
COLO OVERPRESSURE PROTECTION (Continued)
-l operation of both PORVs without exceeding Appendix G limit.
A single failure of
)
a PORV is not assumed due to the short duration that this condition is allowed i
and the low probability of an event occurring during this interval in conjunction with the failure of a PORV to open.
Initiation of both trains of Safety Injectionduringthis4-hourtimeframeduetooperatorerrororasingle failure occurring during testing of a redundant channel are not considered to be credible accidents.
OperationwithallcentrifugalchargingpumpsandbothSafetyInjection l
pumps OPERABLE is acceptable when RCS temperature is greater than 350 F, a single PORV has sufficient capacity to relieve the combined flow rate of all i
pumps.
Above 350 F two RCPs and all pressure safety valves are required to be OPERABLE.
Operation of an RCP eliminates the possibility of a 50'F difference existing between indicated and actual RCS temperature as a result of heat-trans-port effects.
Considering instrument uncertainties only, an indicated RCS tem-perature of 350'F is sufficiently high to allow full RCS pressurization in ac-F cordance with Appendix G limitations.
Should an overpressure event occur in j
these conditions, the pressurizer safety valves provide acceptable and redun-i dant overpressure protection.
When operating below 200*F in MOD'i 5 or MODE 6, Technical Specification 3.5.3.2 allows one Safety Injection punp to be made OPERABLE whenever the RCS has a vent area equal to or greater than 18 square inches.
Cold overpressure protection in this configuration is provided by the 18 square inch or greater mechanical opening in the RCS pressure boundary.
This mechanical opening is larger in size than the 1.58 square inch opening required for normal overpres-i sure protection and is of sufficient size to ensure that the Appendix G limits are not exceeded when an SI pump is operating in MODE 5 or MODE 6.
Addition-ally, when operating in a reduced inventory condition, the larger vent area i
limits RCS pressure during overpressure transients to reduce the possibility i
of adversely affecting steam generator nozzle dams.
When the reactor has been shut down for at least 7 days, the larger vent area also enhances the ability to provide a gravity feed to the RCS from the Refueling Water Storage Tank in the unlikely event that the CCP and SI pumps were unavailable after a loss of RHR.
The Maximum Allowed PORV Setpoint for the Cold Overpressure Mitigation I
System will be revised on the basis of the results of examinations of reactor vessel material irradiation surveillance specimens performed as required by i
I SEABROOK - UNIT 1 B 3/4 4-16 Amendment No. S', 5 l
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l 3/4.4.10 STRUCTURAL INTEGRITY The inservice inspection and testing programs for ASME Code Class 1, 2, and 3 components ensure that the structural integrity and operational readiness i
of these components will be maintained at an acceptable level throughout the i
life of the plant.
These programs are in accordance with Section XI of the ASME Boiler and Pressure Vessel Code and applicable Addenda as required by
[
10 CFR 50.55a(g) except where s)ecific written relief has been granted by the Commission pursuant to 10 C R 50.55a(g)(6)(1).
i Com onents of the Reactor Coolant System were desi ned to provide access to permi inservice iaspections in accordance with Sect on XI of the ASME i
Boiler and Pressure Vessel Code, 1983 Edition and Addenda through Summer 1983, i
I 3/4.4.11 REACTOR COOLANT SYSTEM VENTS t
Reactor Coolant System vents are provided to exhaust noncondensible gases and/or steam from the Reactor Coolant System that could inhibit natural circu-lation core cooling.
The OPERABILITY of least one Reactor Coolant System vent path from the reactor vessel head and the pressurizer steam space ensures that the capability exists to perform this function.
[
The valve redundancy of the Reactor Coolant System vent paths serves to I
minimize the probability of inadvertent or irreversible actuation while ensur.ing that a single failure of a vent velve, power supply, or control system does not i
prevent isolation of the vent path.
The function, capabilities, and testing requirements of the Reactor Coolant System vents are consistent with the requirements of Item II.B.1 of NUREG-0737,
" Clarification of THI Action Plant Requirements," November 1980.
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i SEABROOK - UNIT 1 B 3/4 4-17 Amendment No. 3, 5,
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l 3/4.5 EMERGENCY CORE COOLING SYSTEMS BASES 3/4.5.1 ACCUMULATORS The OPERABILITY of each Reactor Coolant System (RCS) accumulator ensures that a sufficient volume of borated water will be immediately forced into the reactor core through each of the cold legs in the event the RCS pressure falls below the pressure of the accumulators.
This initial surge of water into the core provides the initial cooling mechanism during large RCS pipe ruptures.
The limits on accumulator volume, boron concentration, and pressure ensure that the assumptions used for accumulator injection in the safety analysis are met.
The accumulator power-operated isolation valves are considered to be
" operating bypasses" in the context of IEEE Std. 279-1971, which requires that bypasses of a protective function be removed automatically whenever permissive conditions are not met.
In addition, as these accumulator isolation valves fail to meet single-failure criteria, removal of power to the valves is required.
The limits for operation with an accumulator inoperable for any reason except an isolation valve closed minimizes the time exposure of the plant to a LOCA event occurring concurrent with failure of an additional accumulator which may result in unacceptable peak cladding temperatures.
If a closed isolation valve cannot be immediately opened, ' i full capability of one accumulator is not available and prompt action is rt uired to place the reactor in a mcde where this capability is_not required.
3/4.5.2 and 3/4.5.3 ECCS SUBSYSTEMS The OPERABILITY of two independent ECCS subsystems ensures that sufficient emergency core cooling capability will be available in the event of a LOCA assuming the loss of one subsystem through any single-failure consideration.
Either subsystem operating in conjunction with the accumulators is capable of supplying sufficient core cooling to limit the peak cladding temperatures within acceptable limits for all postulated break sizes ranging from the double-ended break of the largest RCS cold-leg pipe downward.
In addition, each ECCS subsystem provides long-term core cooling capability in the recirculation mode during the accident recovery period.
With the RCS temperature below 350*F, one OPERABLE ECCS subsystem is acceptable witnout single failure consideration on the basis of the stable reactivity condition of the reactor and the limited core cooling requirements.
The limitation for a maximum of one centrifugal charging pump to be OPERABLE and the Surveillance Requirement to verify all charging pumps and safety injection pumps except the required OPERABLE charging pump to be in-operable in MODES 4 and 5.and in MODE 6 with the reactor vessel head on pro-vides assurance _that a mass addition pressure transient can be relieved by the operation of a single PORV or RHR suction relief valve.
SEABROOK - UNIT 1 B 3/4 5-1
EMERGENCY CORE COOLING SYSTEMS BASES 3/4.5.2 and 3/4.5.3 ECCS SUBSYSTEMS (Continued)
When the RCS has a vent area equal to or greater than 18 square inches, one Safety Injection pump may be made OPERABLE when in MODE 5 or MODE 6 (below 200'F). When operating in this configuration, cold overpressure protection is provided by the mechanical vent openingIn the RCS boundary prior to making the equal to or greater than 18 square inches, that is required to be present SI pump OPERABLE.
This required RCS vent area and the surveillance requirement to verify the presence of the RCS vent area provides assurance that a mass addition transient can be relieved and that adequate cold overpressure g
protection is provided.
The Surveillance Requirements orovided to ensure OPERABILITY of each com-ponent ensures that at a minimum, t1e assumptions t. sed in the safety analyses are met and that subsystem OPERABILITY is maintained.
Surveillance Requirements for throttle valve position stops and flow balance testing provide assurance that proper ECCS flows will be maintained in the event of a LOCA.
Maintenance ofproperflowresistanceandpressuredropinthepipingsystemtoeachinjec-tion point is necessary to:
(1) prevent total pump flow from exceeding runout conditions when the system is in its minimum resistance configuration, (2) pro-videtheproperflowsplitbetweeninjectionpointsincccordancewiththe assumptions used in the ECCS-LOCA analyses, and (3) provide an acceptable level of total ECCS flow to all injection points equal to or above that assumed in,the ECCS-LOCA analyses.
3/4.5.4 REFUELING WATER STORAGE TANK The OPERABILITY of the refueling water storage tank (RWST) as part of the ECCS ensures that a sufficient supply of borated water is available for injection by the ECCS in the event of a LOCA.
The limits on RWST minimum volume and boron concentration ensure that:
(1) sufficient water is available within containment to permit recirculation cooling flow to the core and (2) the reactor will remain subcritical in the cold condition following mixing of the RWST and the RCS water volumes with all control rods inserted except for the most reactive control 6ssembly.
These assumptions are consistent with the LOCA analyses.
The contained water volume limit includes ad allowance for water not usable because of tank discharge line location or other physical characteristics.
The limits on contained water volume and boron concentration of the RWST also ensure a pH value of between 8.5 and 11.0 for the solution recirculated within containment after a LOCA.
This pH band minimizes the evolution of iodine and minimizes the effect of chloride and caustic stress corrosion on mechanical systems and components.
SEABROOK - UNIT 1 B 3/4 5-2 Amendment No. 5 I
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