ML20128P799

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Amend 61 to License DPR-21,allowing for Temporarily Bypassing MSLRM Trip Function for Period Not to Exceed 2 Hours,In Order to Allow Condensate Demineralizers to Be Returned to Svc
ML20128P799
Person / Time
Site: Millstone Dominion icon.png
Issue date: 02/19/1993
From: Stolz J
Office of Nuclear Reactor Regulation
To:
Shared Package
ML20128P794 List:
References
NUDOCS 9302250108
Download: ML20128P799 (11)


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  • c NUCLEAR REGULATORY COMMISSION

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((0RTHEAST NUCLEAR ENEBGY COMPANY DOCKET NO. 50-L4ji MILLSTONE NUCLEAR POWER STATION. UNIT 1 MENDMENT TO FACILITY OPERATING LICENSE Amendment No. 61 License No. DPR-21

1. The Nuclear Regulatory Commission (the Commission) has found that:

A. The application for amendment by Northeast Nuclear Energy Company (the licensee), dated January 12, 1993, as supplemented by January 19, 1993, complies with the standards and requirements of the Atomi: Energy Act of 1954, as amanded (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 Commission; 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 Commission'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 Commission's regulations and all applicable requirements have been satisfied.

9302250108 930219 5 DR ADOCK 0500 4

- 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. DPR-21 is hereby amended to read as follows:

(2) Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment No. 61, are hereby incorporated in the license.

The licensee shall operate the facility in accordance.with the.

Technical Specifications.

3. This license amendment is effective as of the date of issuance, to be implemented within 30 days of issuance.

FOR THE NUCLEAR REGULA, TORY COMMISSION oh

a. .

F. Stolz, Director ,

Pro ect Directorate I-y Hision of Reactor Projects-- I/II Office of Nuclear Reactor Regulation

Attachment:

Changes to the Technical Specifications Date of Issuance: February 19, 1993

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I ATTACHMENT TO LICENSE AMENDMENT NO. 61 ,

FACIllTY OPERATING-LICENSE NO. DpR-21 DOCKET NO. 50-245 Replace the following 'pages of the' Appendix A Technical Spacifications' with  ;

the enclosed pages. The revised pages are identified by amendment number and contain vertical lines indicating the areas of change.

Remove Insert -

3/4 1-4 3/4 1-4 3/4 1-5 3/4 1-5 3/4 1-Sa 3/4 2 3/4 2-2 B 3/4 1-4 B 3/4 1-4 B 3/4 1-4a B 3/4 2-3 B 3/4 2-3 B 3/4 2-3a i

TABLE 3.1.1 (Continued)

REACTOR PROTECTION SYSTEM (SCPJJ4, INSTRUMENMTIOC REOUIREMENTS Msrsium Number of f'perable Modes in which Function Inst. Channels Trip Function Trip i.evel Setting Must Be z 0perable Action

  • per Trip (1) REFUEL / STARlVP/ HOT System SHUTDOWN (8,11) STANDBY RUN 2 Turbine Condenser t.ow 2 23 in.119 Vacuum X (3) X (3) X A or C Vacuun 2 Main Steamline Radiation S 7 x Normal Full Power X (12)

Background

X (12) X (12) A or C [

4 (61 Main Steamline isciation i 10% Yalve Closure X (3) X (3) X A or C Valve Closure 2 Turbine Control Valve See Section 2.1.2 F X (4) X (4) X (4) A or C Fast Closure 2 Turbine Stop Valve s 10% Valve Closure X (4) X (4) X (4) A or C Notes: 1. There shall be two operable or tripped trip systems for each function.

2. Permissible to bypass, with control rod block, for reactor protection system reset in REFUEL and SHUTDOWN positions of the reactor mede switch.
3. Bypassed when retttor pressure is < 600 psig.
4. Bypassed when first stage turbine pressure is less than that which corresponds to 50% rated reactor thersal power.

Millstone Unit 1 3/4 1-4 faendment No. JK, JJ. JR61 3062 9

TABLE 3.1.1 (Continued)

Reactor Protection System (Scram) Instrtmentation Requirements Notcs:

5. IFFs are bypassed when mode switch is placed in R H. The detector for each op;rable IRM channel shall be ,

fully inserted until the associated APRM channel is operable and indicating at least 3/125 full scale.

6. The design pemits closure of any one valve without a scram being initiated.
7. May be bypassed when necessary by closing the manual instrument isolation valve for scram of PS-1621 A through D during purgir,g for containment inerting or deinerting.
8. When the reactor is suberitical and the reactor water iemperature is less than 212*F, only the following trip functions need to be operable:
a. Mode Switch in ShVTDOWN
b. Manual Scram
c. High Fhtx IRM
d. Scras Discharge Volume High Level
e. APRM kaduced fligh Flux
9. Not required to be operable when primary containment integrity is not required.
10. With the mode switch in RUM position an inoperative trip function also requires an associated APRM "downscale alarm."
11. Trip functio.1s are not required to be operable if all control rods are fully inserted, and either electrically or hydraulicclly'disanned in accordance with 5pecification 4.1.0.
12. Trip function may be bypassed for up to two hours per occurrence while placing cordensate desineralizers in l service.

Millstone Unit 1 3/4 1-5 Amendment No. J. J2, J5,61

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TABLE 3.1.1 (Continued)

Reactor Protection System (Scram) Instrumentation Requirements CAction: If the first coiumn cannot be met for one of the trip systems, that trip systen shall be tripped. If the first column cannot be met for both trip systems, the appropriate actions listed below shall be taken:

A. Initiate insertion of operable rods.and templete insertion of all operable rods within four hours.

B. . Reduce power level to IRM range and place mode switch in the STARTUP/ HOT STANDBY position within eight hours.

C. Reduce turbine load and close main steam line isolation valves within eight hours.

    • An APRM will be considered inoperable if Caere are less than two LPPJt inputs per level or there are less than 50%

of the nonnal compliment of LPRM's to an APRM.

      • One inch on the water level instrumentation is 127 inches above the top of the active fuel.

Millstone Unit 1 3/4 1-Sa Amendment No. J, JJ, JJ,61 assa e

TABLE 3.2.1 INSTRUMENTATION THAT INITIATES PRIMARY CONTAINMENT ISOLATION PJNCTIONS Minimum Number of Operable'Instrmeent .

Channels Pt.r Trip System (11 Instruments Trio Level Settino Acticn (3) 2 Reactor low Water 1 127 inches above top of active fuel A 2 Reactor Low Low Water 79 (+4-0) inches above top of active fuel A 2 (4) High Drywell Pressure i 2 psig A 2 (2) (5) High Flow Main Steamline i 120% of rated steam flow B 2 of'4 la each of High Temperature Main 2 subchannels Steamline Tunnel 1 200*F B 2 (6) High Radiation Main l steauline Tunnel s 7 times normal rated power background B 2 tow Pressure Main 1 825 psig B Steamlines 2 High Flow Isolation 164 inches 2 trip setting (water differential C Condenser Line on steam line) 1 150 inches.

44 inches 1 trip setting (water differential on water side) 2 35 inches.

(1) Whenever primary crutainment integrity is required, there shall be two operable or tripped trip systems for each function, except for low pressure main steamline which only need be available in the RUN position.

(2) Per each steamline.

(3) Action: If the first column cannot be met for one of the trip syste.as, that trip system shall be tripped. If the first column cannot be met for both trip systems, the appropriate actions listed below shall be takent A. Initiate an orderly shutdown and have reactor in cold shutdown condition in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

B. Initiate an orderly load reduction and have reactor in HOT STAl0BY within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

C. Close isolation valves in isolation condenser system.

(4) May be bypassed when necessa y by closing the marual instrument isolation valve for PS-1621, A through D. during purging for containment inerting or deinerting.

(5) Minimum number of operable instrument channels per trip system requirement does not have to be met fcr a steamline if both containment isolation valves in the lir:e are closed.

(6) Trip function may be bypassed for up to two hocrs per occurrence while plecing condensate demineralizers in !

service. I Millstone Unit 1 3/4 2-2 Ameedwnt ha. J7, 361 eess 4 O e e

3.1 REACTOR PROTECTION SYSTEM BASES Discharge of excessive amounts of radioactivity to the site environs is prevented by the air e,jector off gas monitors which cause an isolation of the main condesser off-gas line, provided the limit for a 15 minute period specified in Specification 3.8 is not exceeded. The trip function may be bypassed for up to two hours per occurrence while placing a e idensate domineralizer in service. This evolution is approximately one half hour in duration. A two hour per occurrence time limit has been selected as a conservative measure to minimize the overall time that this trip function is bypassed. Operating experience has shown that there is risk of a spiirious

' isolation while placing a condensate demineralizer in aervice.

The main steam line isolation valve closure scram is set to scram when the iso 1& tion valves are 10% closed from full open in three out of four lines. This scram anticipates the pressure and flux transient which would occur when the valves close. By scranalng at this setting all thermal margins and pressure limits are met during the resultant transient. Ref.

Section 7.2 of the UFSAR.

A reactor mode switch is provided which actuates, or bypassos, the various scram functions appropriate tc the particular plant operating status.

Ref. Section 7.2 of the UFSAR. ,

The manual scram function is active in all modes, thus providing for a sianual means of rapiily inserting control rods during all modes of reactor ope % tion.

The IRM and APM systems provida protection against excessive power levels and short reactor periods in the REFUEL and STARTUP/ HOT STANDBY modes.

A source range monitor (SRM) system is also provided to supply additional neutron level infomation during startup but has no scram functions. Thus the IRM and APRM systems are required in the REFUEL and STARTUP/ HOT STANDBY modes, in the power range, the APRM provides the required protections; thus, the IRM system is not required in the RUN mode.

The high reactor pressure, high drywell pressure, reactor low water level, end scram discharge volne high level scrams are required for STARTUP/Hof STANDBY and RUN modes of plant operation. They are, therefore, required to be operational for these medes of reactor operation.

The requirement to have all scram functions except those listed in Hote 8 of Table 3.1.1 operable in the REFUEL and SHUTDOWN mode is to assure that shifting to the REFUEL mode during reactor power operation does not diminish the need for the reactor protection system. As indicated in Note 11 of Table 3.1.1, no trip functions are required to be operable if all control rods are fully inserted, and either electrically or hydrsulically disarmed, since this condition assures maximum negative reactivity insertion.

The turbine condenser low vacuum scram is only required during power operation and must be bypassed to start up the unit. At low ?ower conditions, a turbine stop valve closurs does not result in a transient w11ch could not be handled safely by other scrams, such as the APRM.

Millstone Unit 1 B 3/4 1-4 Amendment No. g,61 0080 l

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l 3.1 REACTOR. PROTECTION SYSTEM , I usts I

The requirementthat tho' IRN's be inserted in' the core when the APRM's ,ll read 3/125, se lower, of-full scale assures that there is proper overlap in-- l the neutroa acnitoring systems and thus,. that adequate coverage is provided j for all. ranges of reactor operation. J u

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-Millstone Unit 1 B3/4'l4a Amendment No. 61  :

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3.2 PROTECTIVE INSTRUMENTATION MSIL.-

200*F is low enough to detect leaks of the order of 5 to 10 gpm; thus, it is capable of covering the entire spectrw of breeks. For large breaks, it is back.up to high steam flow instrumentation discussed abova, and for small breaks with the resultant small release of radioactivity, gives isolation before the guidelines of 10 CFR 100 are exceeded.

High radiation monitors in the sain steamline tunnel have been provided to detect gross fuel failure. This instrumentation causes closure of Group 1 valves, the only valves recuired to close to prevent further release to the environment. With the esta)1ished setting of seven times normal background, and main steamline isolation valve closure, fission product release is limited so that 10 CFR IM guideline values are not exceeded for the anst rapid failure mechanism postulated (control rod drop accident). The trip function may be bypassed for up to two hours por occurrence while placing a condensate domineralizer in service. This evolution is approximately one half hour in duration. A two hour per occurrence time limit has been selected as a conservative reasure to minimize the overall time that this tylp function is bypassed. Operating experience has shown that there is risk of a spurious isolation while placing a condensate demineralizer in service.

Pressure instrumentation is provided which trips when main steamline pressure at the turbine drops below 825 psig. A trip of this instrumentation results in closure of Group 1 isolatinn valves. In the " REFUEL," " Shutdown."

and "STARTUP/ HOT STANDBY" mode this trip function is bypassed. This function is provided primarily to provide protection against a pressure regulator malIonction which would cause the control and/or bypass valves to open. With the trip set at 825 psig, inventory loss is limited so that fuel is not uncovered al.d peak clad temperatures are much less than 1500'F; thus, there is no release of fission products other than those in the reactor water.

High pressure actuation of the Isolation Condenser (IC) will be a backup to direct activation on Low-Low level; similar to other ECCS systems. Activa-tion is based on the high pressure signal (1035 PSIG for 15 seconds) which occurs after MSIV closure on low-Low water level, SRV actuation, and subse-quent repressurization. The activation of the IC requires only the opening of normally closed valve IC-3 in the condensate return line. This valve is powered by the safety-grade DC battery. All valves in the system are powered by safety-grade AC or DC power and are also used for containment isolation.

All are normally'in the open position (other than IC-3). The IC system is

, safety Class 2 and is seismically qualified. The shell side water vr me is sufficient for approximately 30 minutes of operation at rated co+ tions without makeup. Two sources of mak9up are available. For small break v. iga-tion, less than 10 minutes of operation is reautred, and g2nera11y at less than rated conditioni.

Millstone Unit 1 B 3/4 2-3 Amendment No. 61 0079

3.2 PROTECTIVE INSTRt.fiENTATION BASES _

Two sensors on the isolation condenser supply and return lines are previded to detect lina failure and actuate isolaticn action. The sansors on the supply and return sides are arranged in a 1 out of 2 logic and to meet the single failure criteria, all sensors and instrumentation are required to be operable. The isolation settings and valve closure times are such as to prevent core uncovery or exceeding site limits.

The instrumentatior, wt.ich initiates ECCS action is arranged in a dual bus system. As for other vital instrumentation arranged in this fashion, the

$3ecification preserves the effectiveness of the system even during periods wien maintenance or testing is being perfonned.

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Millstone Unit 1 B 3/4 2-3a Amennent No. 61 0079

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