ML20149L865

Amend 131 to License NPF-49,clarifying Restriction on Shutdown Margin Monitor Operability While Changing Operational Modes & Correcting TS Numerical Reference So That Number Cited in Agreement W/Amend 99

ML20149L865
Person / Time
Site:	Millstone
Issue date:	11/14/1996
From:	Mckee P NRC (Affiliation Not Assigned)
To:
Shared Package
ML20149L867	List: ML20149L865 ML20149L872
References
NUDOCS 9611190197
Download: ML20149L865 (7)

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1 UNITED STATES s

j NUCLEAR REGULATORY COMMISSION t

WASHINGTON, D.C. 20066 4001 i

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NORTHEAST NUCLEAR ENERGY COMPANY. ET AL.

DOCKET NO. 50-423 i

MILLSTONE NUCLEAR POWER STATION. UNIT NO. 3 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No.131 License No. NPF-49 1.

The Nuclear Regulatory Comission (the Comission) has found that:

A.

The application for amendment by Northeast Nuclear Energy Company, et al. (the licensee) dated June 3,1996, as supplemented October 23, 1996, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Comission'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 Comission; 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 Comission's regulations; 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 Comission's regulations and all applicable requirements have been satisfied.

9611190197 961114 PDR ADOCK 05000423 P

PDR

. 2.

Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Facility Operating License No. NPF-49 is hereby amended to read as follows:

(2)

Itchnical Soecifications The Technical Specifications contained in Appendix A, as revised through Amendment No. 131, and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto are.hereby incorporated in the license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.

J 3.

This license amendment is effective as of the date of its issuance, to be implemented within 60 days of issuance.

j FOR THE NUCLEAR REGULATORY COMMISSION i

Phillip F. McKee Deputy Director for Licensing Special Projects Office Office of Nuclear Reactor Regulation

Attachment:

Changes to the Technical Specifications Date of Issuance: November 14, 1996

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ATTACHMENT TO LICENSE AMENDMENT NO.131 FACILITY OPERATING LICENSE NO. NPF-49 DOCKET NO. 50-423 f

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 areas of change.

Remove Insert 3/4 3-6 3/4 3-6 B 3/4 3-3 8 3/4 3-3 B 3/4 3-3a B 3/4 3-3b

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TABLE 3.3-1 (Continued) i ACTION STATEMENTS (Continued)

ACTION 3 -

With the number of channels OPERABLE one less than the Minimum i

Channels OPERABLE requirement and with the THERMAL POWER level:

a.

Below the P-6 (Intermediate Range Neutron Flux Interlock)

Setpoint, restore the inoperable channel to OPERABLE 1

status prior to increasing THERMAL POWER above the P-6 Setpoint, and b.

Above the P-6 (Intermediate Range Neutron Flux Interlock)

Setpoint but below 105 of RATED THERMAL POWER, restore the inoperable channel to OPERABLE status prior to increasing THERMAL POWER above 105 of RATED THERMAL POWER.

ACTION 4 -

With the number of OPERABLE channels one less than the Minimum Channels OPERABLE requirement, suspend all operations involving positive reactivity changes.

ACTION 5 -

(a) With the number of OPERABLE channels one less than the Minimum Channels OPERABLE requirement, restore the inoperable channel to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or suspend all operations involving positive reactivity changes via dilution and rod withdrawal, and verify valves as per Specification 4.1.1.2.2 are closed and secured in position within the next four hours.

(b) With no channels OPERABLE, suspend all operations involving positive reactivity changes via dilution and rod withdrawal, and verify valves per Specification 4.1.1.2.2 are closed and secured in position within the next 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. Verify compliance with the SHUTDOWN MARGIN requirements of Specification 3.1.1.1.2 or 3.1.1.2 as applicable within the next hour.

Continue to verify valves closed and secured every 14 days and verify SHUTDOWN MARGIN every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

l ACTION 6 -

With the number of OPERABLE channels one less than the Total Number of Channels, STARTUP and/or POWER OPERATION may proceed provided the following conditions are satisfied:

The inoperable channel is placed in the tripped cor.dition a.

within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and b.

The Minimum Channels OPERABLE requirement is met; however, the inoperable channel may be bypassed for up to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> for surveillance testing of other channels per Specification 4.3.1.1.

(Not used)

ACTION 7 With less than the Minimus Number of Channels OPERABLE, within ACTION 8 I hour detemine by observation of the associated pemissive annunciator window (s) that the interlock is in its required state fer the existing plant condition, or apply Specification 3.0.3.

MILLSTONE - INIIT 3 3/4 3-6 Amendment No. F, M,131 osse

INSTRINIENTATION i

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REACTOR TRL* SYSTEM INSTRUMENTATION and ENGINEERED SAFETY FEATURES ACTUATION l

SYSTEM INS":tuMENTATION (Continued)

The Engineered Safety Features Actuation System interlocks perfom the i

following functions:

1 P-4 Reactor tripped - Actuates Turbine trip, closes main feedwater valves on T below Setpoint, prevents the opening of the main feedwatervUveswhichwereclosedbyaSafetyInjectionorHigh Steam Generator Water Level signal, allows Safety Injection block j

so that components can be reset or tripped.

e Reactor not tripped - prevents manual block of Safety Injection.

i P-11 On increasing pressurizer pressure, P-Il automatically reinstates j

Safety Injection actuation on low pressurizer pressure and low steam line pressure. On decreasing pressure, P-ll allows the manual block of Safety Injection actuation on low pressurizer pressure and low steam line pressure.

P-12 On increasing reactor coolant loop temperature, P-12 automatically i

provides an arming signal to the Steam Dump System. On decreasing reactor coolant loop temperature, P-12 automatically removes the aming signal from the Steam Dump System.

P-14 On increasing steam generator water level, P-14 automatically 1

trips all feedwater isolation valves, main feed pumps and main j

turbine, and inhibits feedwater control valve modulation.

j Shutdown Margin Monitors Backaround:

The purpose of the Shutdown Margin Monitors (Sl#4) is to annunciate an increase in core subcritical multiplication allowing the operator at least 15 minutes response time to mitigate the consequences of the inadvertent addition of unborated primary grade water (boron dilution event) into the Reactor Coolant System (RCS) when the reactor is shut down (Modes 3, 4, and 5).

l The SMis utilizes two channels of source range instrumentation (GM detectors).

Each channel provides a signal to its applicable train of Smi. The Set channel uses the last 600 or umre counts to calculate the count rate and 1

updates the measurement after 30 new counts or I second, whichever is longer.

Each channel has 20 registers that hold the counts (20 registers X 30 count =

600 counts) for averaging the rate. As the count rate decreases, the longer it takes to fill the registers (fill the 30 count minimum). As the instrument's measured count rate decreases, the delay time in the instrument's response increases. This delay time leads to the requirement of a minimum count rate for OPERABILITY.

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MILLSTONE - UNIT 3 B 3/4 3-3 Amendment No. 131 a

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BASES (continued) i i

During the dilution event, count rate will increase to a level above the norma steady state count rate. When this new count rate level increases l

above the instrument's setpoint, the channel will alarm alerting the operator-of the event.

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Anolicable Safety Analysis The SIM senses abnomal increases in the source range count per second and l

alarus the operator of an inadvertent dilution event. This alam will occur at least 15 minutes prior to the reactor achieving criticality. This 15 minute window allows adequate operator response time to terminate the i

i dilution, FSAR Section 15.4.6.

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1 LC0 3.3.1 provides the requirements for OPERABILITY of the instrumentation of l

the SfMs that are used to mitigate the boron dilution event. Two trains are j

required to be OPERA 8LE to provide protection against single failure.

l Acolicability l

The Sim must be OPERABLE in MODES 3, 4, and 5 because the safety analysis j

identifies this system as the primary means to alert the operator and mitigate the event. The SMMs are allowed to be blocked during start up activities in MODE 3 in accordance with approved plant procedures. The alarm is blocked to l

allow the SIM channels to be used to monitor the 1/M approach to criticality.

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i The SIM are not required to be operable in MODES I and 2 as other RPS is credited with accident mitigation, over temperature delta temperature and power range neutron flux high (low setpoint of 25 percent RTP) respectively.

l The SIMs are not required to be OPERABLE in Mode 6 as the dilution event is precluded by administrative controls over all dilution flow paths (Technical i

Specification 4.1.1.2.2).

Actions Channel inoperability of the SIMs can be caused by failure of the channel's electronics, failure of the channel to pass its calibration procedure, or by the channel's count rate falling below the minimum count rate for operability.

This can occur when the count rate is so low that the channel's delay time is in excess of that assumed in the safety analysis.

In any of the above conditions, the channel must be declared inoperable and the appropriate action statement entered.

If the SIMs are declared inoperable due to low count rates, an RCS heatup will cause the SDM channel count rate to increase to above the minimum count rate for operability. Allowing the plant to increase modes will actually return the SIMs to OPERABLE status. Once the SIM channels are above the minimum count rate for operability, the channels can be declared operable and the LC0 action statements can be exited.

5(a) With one train of SDM inoperable, Action 5(a) requires the inoperable train to be returned to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.

In this condition, the remaining SIM train is adequate to provide protection.

If the above required action cannot be ret, alternate compensatory actions must be MILLSTONE - UNIT 3 B 3/4 3-3a Amendment No.131 meo

BASES (continued) performed to provide adequate protection from the boron dilution event.

All operations involving positive reactivity changes associated with RCS dilutions and rod withdrawal must be suspended, and all dilution flowpaths must be closed and secured in position (locked closed per Technical Specification 4.1.1.2.2) within the following 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.

5(b) With both trains of SMM inoperable, alternate protection must be provided:

1.

Positive reactivity operations via dilutions and rod withdrawal are suspended. The intent of this action is to stop any planned dilutions of the RCS. The SMMs are not intended to monitor core reactivity during RCS temperature changes.

The alarm setpoint is routinely reset during the plant heatup due to the increasing count rate.

During cooldowns as the count rate decreases, baseline count rates are continually lowered automatically by the SMMs.

The Millstone Unit No. 3 boron dilution analysis assumes steady state RCS temperature conditions.

2.

All dilution flowpaths are isolated and placed under administrative control (locked closed). This action provides redundant protection and defense in depth (safety overlap) to the SMMs.

In this configuration, a boron dilution event (BDE) cannot occur.

This is the basis for not having to analyze for BDE in Mode 6.

Since the BDE cannot occur with the dilution flow paths isolated, the SMMs are not required to be operable as the event cannot occur and operable SMMs provide no benefit.

3.

Increase the shutdown margin surveillance frequency from every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. This action in combination with the above, provide defense in depth and overlap to the loss of the SMMs.

Surveillance Reauirements The SMMs are subject to an ACOT every 92 days to ensure each train of SMM is fully operational. This test shall include verification that the SHMs are set per the Core Operating Limit Report.

3/4.3.3 MONITORING INSTRUMENTATION 3/4.3.3.1 RADIATION MONITORING FOR PLANT OPERATIONS The OPERABILITY of the radiation monitoring instrumentation for plant operations ensures that:

(1) the associated action will be initiated when the radiation level monitored by each channel or combination thereof reaches its Setpoint, (2) the specified coincidence logic is maintained, and (3) suffi-cient redundancy is maintained to permit a channel to be out-of-service for testing or maintenance.

The radiation monitors for plant operations senses radiation levels in selected plant systems and locations and determines whether or not predetermined limits are being exceeded.

If they are, the signals are combined into logic matrices sensitive to combinations indicative of various accidents and abnormal conditions.

Once the required logic combination is completed, the system sends actuation signals to initiate alarms.

MILLSTONE - UNIT 3 B 3/4 3-3b Amendment No. Up,131 0660