ML19210D064

Revised Pages Per Proposed Tech Spec Change 79-8 for Core Spray & Containment Cooling Sys

ML19210D064
Person / Time
Site:	Pilgrim
Issue date:	11/13/1979
From:	BOSTON EDISON CO.
To:
Shared Package
ML19210D061	List: ML19210D060 ML19210D064
References
NUDOCS 7911200489
Download: ML19210D064 (7)

Text

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LIMITING CONDITIONS FOR OPERATION SURVEILLANCE EQUIPMENT 3.5.A Core Spray and LPCI Subsystems 4.5.A Core Spray and LPCI Subsystems (con t ' d) (cont'd)

Check Once/ day Calibrate Once/3 months Test Once/3 months

2. From and after the date that one 2. When it is determined that one core of the core spray subsystems is spray subsystem is inoperable, made or found to be inoperable the operable core spray subsystem, for any reason, continued reactor the LPCI subsystem and the diesel operation is permissible during generators shall be demonstrated to the succeeding seven days, pro- be operable immediately. The oper-vided that during such seven days able core spray subsystem shall be all active components of the other demonstrated to be operable daily core spray subsystem and active thereafter.

components of the LPCI subsystem and the diesel generators are op-erable.

3. The LPCI Subsystems shall be oper- 3. LPCI Subsystem Testing shall be as able whenever irradiated fuel is follows:

in the reactor vessel, and prior to reactor startup from a Cold a. Simulated Automa- Once/ Operating

') Condition, except as specified tic Actuation Test Cycle in3.5.A.4,3.5.A.5and3.5.F.5.l b. Pump Operability Once/ month

c. Motor Operated Once/ month valve operability

d. Pump Flow Rate Once/3 months Three LPCI pumps shall deliver 14,400 gpm against a system head corresponding to a vessel pressure of 20 psig.

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LIMITING CONDITION FOR OPERATION SURVEILLANCE REQUIREMENT 3.5,F Minimum Low Pressure Cooling and Diesel Generator Avail-ability (Cont'd)

3. When irradiated fuel is in the re-actor vessel and the reactor is in the Cold shutdown Condition, both core spray systems, the LPCI and containment cooling subsystems may be inoperable, provided no work is being done which has the potential for draining the reactor vessel.

4. During a refueling outage, for a period of thirty days, refueling operation may continue provided that one core spray system or the LPCI system is operable or spec-ification 3.5.F.5 is met.

5. When irradiated fuel is in the reactor vessel and the reactor is in the Refueling Condition.with the torus drained, a single control rod drive mechanism may be removed,1f both of the following conditions are satis-fied:

a) No work on the reactor vessel, in addition to CRD removal, will be performed which has the po-tential for exceeding the maximum leak rate from a single control blade seal if it became unseated.

b) 1) the core spray systems are operable and aligned with a suction path from the condensate storage tanks, 11) the conden-sate storage tanks shall contain at least 200,000 gallons of usable water and the refueling cavity and dryer / separator pool shall be flooded to at 1 cast elevation 114'-0".

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SURVEILLANCE REQUIREMENT LIMITING CONDITION F0F OPERATION 4.5.H Maintenance of Filled Discharge 3.5.H Maintenance of Filled Dis-charge Pipe P,ipe i

Whenever core spray subsystems, LPCI The following surveillance requirements subsystem, HPCI, or RCIC are required shall be adhered to to assure that the to be operable, the discharge piping discharge piping of the core spray sub-from the pump discharge of these sys- systems, LPCI subsystem, HPCI and RCIC are filled:

tems to the last block valve shall be filled. Evety month prior to the testing of 1.

the LPCI subsystem and core spray subsystem, the discharge piping of these systems shall be vented from the high point and water flow ob-served.

2. Following any period where the LPCI subsystem or core spray subsystems have not been required to be oper-able, the discharge piping of the inoperable system shall be ventea from the high point prior to the return of the system to service.

3. Whenever the HPCI or RCIC system is lined up to take suction from the torus, the discharge piping of the HPCI and RCIC shall be vented from the high point of the system and water flow observed on a monthly basis.

4. The pressure switches which monitor the discharge lines to ensure that they are full shall be functionally tested every month and calibrated every three months.

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BASES:

3.5.F Minimum Low Pressure Cooling and Diesel Generator Availability The purpose of Specification F is to assure that adequate core cooling equip-ment is nvailable at all times. If, for example, one core spray were out of service and the diesel which powered the opposite core spray were out of service, only 2 LPCI pumps would be available. It is during refueling outages that major maintenance is performed and during such time that all low pres-sure core cooling systems may be out of service. This specification provides that should this occur, no work will be performed on the primary system which could lead to draining the vessel. This work would include work on certain control rod drive components and recirculation system. Specification F allows removal of one CRD mechanism while the torus is in a drained condition without compromising core cooling capability. The available core cooling capability for a potential draining of the reactor vessel while this work is performed is based on an estimated drain rate of 300 gpm if the control rod blade seal is unseated. Flooding the refuel cavity and dryer / separator pool to elevation 114' 0" corresponds to approximately 350,000 gallons of water and will provide core cooling capability in the event leakage from the control rod drive does occur.

A potential draining of the reactor vessel (via control rod blade leakage) would allow this water to enter into the torus and after approximately 140,000 gallons have accumulated (needed to meet minimum NPSH requirements for the LPCI and/or core spray pumps), the torus would be able to serve as a common suction header.

This would allow a closed loop operation of the LPCI system and the core spray system (once re-aligned) to the torus. In addition, the other core spray system is lined up to the condensate storage tanks which can supplement the refuel cavity and dryer / separator pool water to provide core flooding, if required.

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Specification 3.9 must also be consulted to determine other requirements for the diesel generators.

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SURVEILLANCE REQUIREMENTS LIMITING CONDITIONS FOR OPERATION 4.7 CONTAINMENT SYSTEMS 3.7 CONTAINMENT SYSTEMS Applicability:

Applicability: ,

Applies to the operating status of the primary Applies to the primary and secondary containment integrity.

and secondary containment systems.

Objective: Objective:

To assure the integrity of the primary and To verify the integrity of the primary secondary containment systems. and secondary containment.

Specification: Specification:

Primary Containment A. Primary Containment A.

At any time that the nuclear system is 1. a. The suppression chamber water

1. level and temperature shall pressurized above atmospheric pressure be checked once per day.

or work is oeing done which has the potential to drain the vessel, the pressure suppression pool water volume b. Whenever there is indication of relief valve operation or and temperature shall be maintained within the following limits except as testing which adds heat to the specified in 3.7. A.2 and 3.7. A. 3. f suppression pool, the pool temperature shall be con-

a. Minimum water volume - 84,000 ft 3 tinually monitored and also observed and logged every 5 3

b. Maximum water volume - 94,000 ft minutes until the heat addition is terminated.

c. Maximum suppression pool temperature during normal continuous power c. Whenever there is indication of reliaf valve operation with operation shall be $ 80 F, except as specified in 3.7.A.I.e. the temperature of the suppression pool reaching 160 F

d. Maximum suppression pool temperature or inore and the primary coolant during RCIC, HPCI or ADS operation system pressure greater than shall be 1 90 F, except as specified 200 psig, an external visual in 3.7.A.I.e.

examination of the suppression chamber shall be conducted

e. In order to continue reactor power before resuming power operation, operation, the suppression chamber pool temperature must be reduced to d. A visual inspection of the 180 F within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, suppression chamber interior, including water line regions, shall be made at each major

f. If the suppression pool temperature exceeds the limits of Specification refueling outage.

3.7.A.I.d RCIC, HPCl or ADS testing shall be termineled and suppression pool cooling shall be initiated.

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g. If the suppression pool temperature during reactor power operation exceeds 110 F, the reactor shall be scrammed.

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LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS

2. Primary containment integrity shall be 2. Integrated Leak Rate Testing maintained at all times when the reactor is critical a. The primary containment or when the reactor water integrity shall be demon-temperature is above 212 F and strated by performing an fuel is in the reactor vessel except Integrated Primary Con-while performing "open vessel" physics tainment Leak Test (IPCLT) te9ts at power levels not to exceed in accordance with either 5 Mw(t). Method A or Method B, as follows:

Method A Perform leak rate test prior to initial unit operation at the test pressure 45 psig, P t (45), to obtain measured leak rate Lm (45), or Method B Perform leak rate test prior to initial unit operation at the test pressure of 45 psig,

?g (45), and 23 psig, P g (23),

to obtain the measured leak rates, L, (45) and to (23),

respectively.

3. The suppression chamber can be drained if the conditions as specified in Sections 3.5.F.3 and 3.5.F.5 of this Technical Specification are adhered to.

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BASES:

3. 7. A & 4. 7. A Primary Containment The integrity of the primary containment and operation of the core, standby cooling system in combination limit the off-site doses to values less than those suggested in 10 CFR 100 in the event of a break in the primary system piping.

Thus, containment integrity is specified whenever the potential for violation of the primary reactor system integrity exists. Concern about such a violation exists whenever the reactor is critical and above atmospheric pressure.

An exception is made to this requirement during initial core load-ing and while the low power test program is being conducted and ready access to the reactor vessel is required. There will be no pressure on the system at this time, thus greatly reducing the chances of a pipe break. The reactor may be taken critical during this period; however, restrictive operating procedures will be in effect again :o minimize the probability of an accident occurring. Procedures and the Rod Worth Minimirtr would limit control worth such that a rod drop would not result in any fuel damage. In addition, in the unlikely event that an excursion did occur, the reactor building and standby gas treatment system, which shall be operational during this time, offer a sufficient barrier to keep off-site doses well below 10 CFR 100 limits.

The pressure suppression pool water provides the heat sink for the reactor primary system energy release following a postulated rupture of the system.

The pressure suppression chamber water volume must absorb the associated decay and 1035structural psig. sensible heat released during primary system blowdown from Since all of the gases in the drywell are purged into the pressure supression chamber air space during a loss-of-coolant accident, the pressure resulting from isothermal compression plus the vapor pressure of the liquid must not exceed 62 psig, the suppression chamber maximum pressure. The design volume that of the suppression chamber (water and air) was obtained by considering the total volume of reactor coolant to be condensed is discharged to the suppression chamber. chamber and that the drywell volume is purged to the suppression Using the minimum or maximum water volumes given in the specification, containment pressure during the design basis accident is approximately 45 p*ig which is below the maximum of 62 psig. Maximum water volume of 94,000 ft3 results in a downcomer submergency of 4'9" and the minimum volume of 84,000 f t 3 results in a' submergence approximately 12-inches less. The majority of the Bodega tests were run with a submerged length of 4 feet and with complete condensation. Thus, with respect to downcomer submergency, this specification is adequate.

Should it be necessary to drain the suppression chamber, provision will be made to maintain those requirements as described in Section 3.5.F BASES of this Tehenical Specification. '

Experimental data indicates that excessive steam condensing loads can be avoided if the peak temperature of the pressure suppression pool is maintained below at 1600F during the discharge exit.any period of relief-valve operation with sonic conditions Specifications have been placed on the envelope of reactor operating conditions so that the reactor can be depressurized in a timely manner chamber to avoid the regime of potentially high pressure suppression loadings.

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