ML18066A201

Proposed Tech Specs,Reflecting Reduced Min Reactor Vessel Flow Rate Assumption in Accident Analyses

ML18066A201
Person / Time
Site:	Palisades
Issue date:	06/17/1998
From:	CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:
Shared Package
ML18066A199	List: ML18066A198 ML18066A201
References
NUDOCS 9806230098
Download: ML18066A201 (10)

Text

ATTACHMENT 1 CONSUMERS POWER COMPANY PALISADES PLANT DOCKET 50-255 TECHNICAL SPECIFICATIONS CHANGE REQUEST PRIMARY COOLANT SYSTEM FLOW Proposed Pages 3 Pages

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9 ao623ooqa -900617 PDR ADOCK 05000255 p PDR

3.1 PRIMARY COOLAN~YSTEM Applicability Applies to the operable status of the primary coolant system.

Obiective To specify certain conditions of the primary coolant system which must be met to assure safe reactor operation.

Specifications 3 .1.1 Operable Components

a. At least one primary coolant pump or one shutdown cooling pump with a flow rate greater than or equal to 2810 gpm shall be in operation whenever a change is being made in the boron concentration of the primary coolant and the plant is operating in cold shutdown or above, except during an emergency loss of coolant flow situation. Under these circumstances, the boron concentration may be increased with no primary coolant pumps or shutdown cooling pumps running.

b. Four primary coolant pumps shall be in operation whenever the reactor is operated above hot shutdown, with the following exception:

Before removing a pump from service, thermal power shall be reduced as specified in Table 2.3.1 and appropriate corrective action implemented. With one pump out of service, return the pump to service within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> (return to four-pump operation) or be in hot shutdown (or below) with the reactor tripped (from the C-06 panel, opening the 42-01 and 42-02 circuit breakers) within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. Start-up (above hot shutdown) with less than four pumps is not permitted and power operation with less than three pumps is not permitted.

c. The measured four prim~..r.Y.. . £9.9.1.~n.t. . Pumps operating reactor vessel fl ow shall be :~::::::;19gj~j!QQ!M@Jpfil 1qo. 7 x 10° l b/lw or greater, wheH eorreeted to 532°F.

d. Both steam generators shall be capable of performing their heat transfer function whenever the average temperature of the primary coolant is above 300°F.

e. The AXIAL SHAPE INDEX (ASI) shall be maintained within the limits specified in the COLR.

(1) When the ASI exceeds the limits specified in the COLR, within 15 minutes initiate corrective actions to restore the ASI to the acceptable region. Restore the ASI to acceptable values within one hour or be at less than 70%

of rated powerwithin the following two hours.

3-lb Amendment No. 3-l, 85, -H-8, tt9, 1:-34, B-1-, t6t, -1&9,

3."l e

PRIMARY COOLANT SYSTEM

'3 .1.1 Operable Components (continued)

Basis When primary coolant boron concentration is being changed, the process must be uniform throughout the primary coolant system volume to prevent stratification of primary coolant at lower boron concentration which could result in a reactivity insertion. Sufficient mixing of the primary coolant is assured if one shutdown cooling or one primary coolant pump is in operation .OJ The shutdown cooling pump wi 11 circulate the primary system volume in less than 60 minutes when operated at rated capacity. By imposing a minimum shutdown cooling pump flow rate of 2810 gpm, sufficient time is provided for the operator to terminate the boron dilution under asymmetric flow conditions.cs> The pressurizer volume is relatively inactive, therefore it will tend to have a boron concentration higher than the rest of the primary coolant system during a dilution operation. Administrative procedures will provide for use of pressurizer sprays to maintain a nominal spread between the boron concentration in the pressurizer and the primary system during the addition of boron.'~

The 57% pressurizer level, in section 3.l.lh(4), is not an analytical result, but simply a decision point between having and not having a bubble. It was chosen to agree with the maximum programmed level during power operation.

The limitation, in section 3.1.li, on operating P-50A and P-508 together with Tc below 300°F allows the Pressure Temperature limits of Figures 3-1 and 3-2 to be higher than they would be without this limit.

The FSAR safety analysis was performed assuming four primary coolant pumps were operating for accidents that occur during reactor operation. Therefore, reactor startup above hot shutdown is not permitted unless all four primary coolant pumps are operating. Operation with three primary coolant pumps is permitted for a limited time to allow the restart of a stopped pump or for reactor internals vibration monitoring and testing.

Requiring the plant to be in hot shutdown with the reactor tripped from the C-06 panel, opening the 42-01 and 42-02 circuit breakers, assures an inadvertent rod bank withdrawal will not be initiated by the control room operator. Both steam generators are required to be operable whenever the temperature of the primary coolant is greater than the design temperature of the shutdown cooling system to assure a redundant heat removal system for the reactor.

The transient analyses which require a minimum vessel flow rate assumption were performed assuming a vessel volumetric flow rate of 352,000 gpm, which corresponds to an analytical limit of 341,400 gpm when adjusted for 3% flow measurement uncertainty. For calculations which require a core flow rate, the analytical limit is further reduced by 3% to account for core bypass, to 331,200 gpm.' 3>

• A DNB analysis was performed for the limiting AOO which is not protected by a reactor trip, in a parametric fashion to determine the core inlet temperature as a function of pressure and flow for which the minimum DNBR is equal to the DNB correlation safety limit. Subsequent confirming analyses include the following uncertainties and allowances: 2% of rated power for power measurement; +/-0.06 for ASI measurement; +/-22 psi for pressurizer pressure; 4

+/-7°F for inlet temperature; and 3% measurement and 3% bypass for core flowC >.

In addition, transient biases were included in the determination of the allowable reactor inlet temperature.

3-2 Amendment No. 61, 85, tt1, HS, t, B-1, t63-, +&9,-tt-t,

3.1 PRIMARY COOLANT SYSTEM Basis (continued)

The limits of validity of the Tc equation are:

1800 ~ pressure ~ 2200 psia 100.0 x 106 ~ Vessel Flow s 150 x 10 6 lb/h ASI as shown in the COLR.

With measured primary coolant system flow rates> 150 Mlbm/hr, limiting the maximum allowed inlet temperature to the Tc LCO at 150 Mlbm/hr increases the margin to DNB for higher PCS flow rates(~.

The Axial Shape Index alarm channel is being used to monitor the ASI to ensure that the assumed axial power profiles used in the development of the inlet temperature LCO bound measured axial power profiles. The signal representing core power (Q) is the auctioneered higher of the neutron flux power and the Delta-T power. The measured ASI calculated from the excore detector signals and adjusted for shape annealing (Y 1) and the core power constitute an ordered pair (Q,Y 1) . An alarm signal is activated before the ordered pair exceed the boundaries specified in the COLR.

The requirement that the steam generator temperature be s the PCS temperature when forced circulation is initiated in the PCS ensures that an energy addition caused by heat transferred from the secondary system to the PCS will not occur. This requirement applies only to the initiation of forced circulation (the start of the first primary coolant pump) when the PCS cold leg temperature is< 430°F. However, analysis (Reference 6) shows that under limited conditions when the Shutdown Cooling System is isolated from the PCS, forced circulation may be initiated when the steam generator temperature is higher than the PCS cold leg temperature.

References (1) Updated FSAR, Section 14.3.2.

(2) Updated FSAR, Section 4.3.7.

(3) EMF 97-051, Revision 1, Table 2.1.

(4) EMF-98-013, Revision 0, Section 15.0.7.1 (5) ANF-90-078 (6) Consumers Power Company Engineering Analysis EA-A-NL-89-14-1 3-3 Amendment No. 3+, 5t, W, -HB, ffi, -134, B-1-, t-43-, +/-56-, t59, ~. H-t,

ATTACHMENT 2 CONSUMERS POWER COMPANY PALISADES PLANT DOCKET 50-255 TECHNICAL SPECIFICATIONS CHANGE REQUEST PRIMARY COOLANT SYSTEM FLOW Existing Pages Marked to Show Proposed Changes 3 Pages

PRIMARY COOLA~SYSTEM Applicability Applies to the operable status of the primary coolant system.

Ob.iective To specify certain conditions of the primary coolant system which must.

be met to assure safe reactor operation.

Specifications 3.1.1 Operable Components

a. At least one primary coolant pump or one shutdown cooling pump

• with a flow rate greater than or equal to 2810 gpm shall be in operation whenever a change is being made in the boron concentration of the primary coolant and the plant is operating in cold shutdown or above, except during an emergency loss of coolant flow situation. Under these circumstances, the boron concentration may be increased with no primary coolant pumps or shutdown cooling pumps running.

b. *Four primary coolant pumps shall be in operation whenever the reactor is operated above hot shutdown, with the following exception:

Before removing a pump from service, thermal power shall be reduced as specified in Table 2.3.l and appropriate corrective action implemented. With one pump out of service, return the pump to service within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> (return to four-pump operation) or be in hot shutdown {or below) with the reactor tripped (from the C-06 panel, opening the 42-01 and 42-02 circuit breakers) within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. Start-up (above hot shutdown) with less than four pumps is not permitted and power operation with less than three pumps is not permitted.

c. The measured four primary coolant pumps operating reactor vessel fl ow sha 11 be 1~!]11i:§?.!:~::qgpi!iiP:m 140. 7 )( 10~ lb/hr or greater, ~*Jhen correcteff .. fo ....5J.2'°F~* ....

d. Both steam generators shall be capable of performing their heat transfer function whenever the average temperature of the primary coolant is above 300°F.

e. The AXIAL SHAPE INDEX (ASI) shall be maintained within the limits specified in the COLR.

(1) When the ASI exceeds the limits specified in the COLR, within 15 minutes initiate corrective actions to restore the ASI to the acceptable region. Restore the ASI to acceptable values within one hour or be at less than 70%

of rated power within the following two hours.

3-lb Amendment No. J.l., 8-§., 18, H9, H4, H-7, -141-, &9,

3.1 3 .1.1 PRIMARY COOLA~YSTEM (continued)

Operable Components Basis When primary coolant boron concentration is being changed, the process must be.uniform throughout the primary coolant system volume to prevent stratification of primary coolant at lower boron concentration which could result in a reactivity insertion. Sufficient mixing of the primary coolant is assured if one shutdown cooling or one primary coolant pump is in operation.Cl} The shutdown cooling pump will circulate the primary system volume in less than 60 minutes when operated at rated capacity. By imposing a minimum shutdown cooling pump flow rate of 2810 gpm, sufficient time is provided for the operator to terminate the boron dilution under asymmetric flow conditions.cs> The pressurizer volume is relatively inactive, therefore it will tend to have a boron concentration higher than the rest of the primary coolant system during a dilution operation.. Administrative procedures will provide for use of pressurizer sprays to maintain a nominal spread between the boron concentration in the pressurizer and the primary system during the addition of boron _<2l The 57% pressurizer level, in section 3.l.lh(4), is not an analytical result, but simply a decision point between having and not having a bubble. It was chosen to agree with the maximum programmed level during power operation.

The limitation, in section 3.1.li, on operating P-50A and P-508 together with Tc below 300°F allows the Pressure Temperature limits of Figures 3-1 and 3-2 to be higher than they would be without this limit.

The FSAR safety analysis was performed. assuming four primary coolant pumps were operating for accidents that occur during reactor operation. Therefore, reactor startup above hot shutdown is not permitted unless all four primary coolant pumps are operating. Operation with three primary coolant pumps is permitted for a limited time to allow the restart of a stopped pump or for reactor internals vibration monitoring and testing.

Requiring the plant to be in hot shutdown with the reactor tripped from the C-06 panel, opening the 42-01 and 42-02 circuit breakers, assures an inadvertent rod bank withdrawal will not be initiated by the control room operator. Both steam generators are required to be operable whenever the temperature of the primary coolant is greater than the design temperature of the shutdown cooling system to assure a redundant heat removal system for the reactor.

The traflsieflt aflalyses were performed assumifl~ a *vessel flow at hot zero power (932°F) of 140. 7 x 10° le/hr n,Jn.~. ~. . . . §'..t.. .t..~. . . . ~.9.<;.9.4.ft..t.. . JQX..JI.PK. . m~.<:!.~.4.r.~m~rit Ii:

.-:~~"::m~~}~~~!~:~~

i~Ml:~::tiini:~:ini:~&1.i~::ir~~~~~~~ ~~~e}~1 ~ ~:~~9 u~~!~t:~~ir!! s a~:~~t!:f=v~~*~:~ces = 2%

ar*fafed'**µovie*r-**-rcrr**j'.fower measurement; +/-0. 06 for AS I measurement; +/-22 psi for pressurizer pressure; +/-7°F for inlet temperature; and 3% measurement and 3%

bypass for core flow 14>. In addition, transient biases were included in the determination of the allowable reactor inlet temperature.

3-2 Amendment No. 61, 85, ttr, tta, t3+, t3-1-, t6-3-, 1.-69, 171

3.1 PRIMARY COOLANT SYSTEM Basis (continued)

The limits of validity of the Tc equation are:

1800 ~ pressure ~ 2200 psia 100.0 x 106 ~ Vessel Flow ~ 150 x 106 lb/h ASI as shown in the COLR.

With measured primary coolant system flow rates> 150 M lbm/hr, limiting the maximum allowed inlet temperature to the Tc LCO at 150 M lbm/hr increases the margin to DNB for higher PCS flow rates 1aj.

The Axial Shape Index alarm channel is being used to monitor the ASI to ensure that the assumed axial power profiles used in the development of the inlet temperature LCO bound measured axial power profiles. The signal representing core power (Q) is the auctioneered higher of the neutron flux power and the Delta-T power. The measured ASI calculated from the excore detector signals and adjusted for shape annealing (Y 1) and the core power constitute an ordered pair (Q.Y 1) . An alarm signal 1s activated before the ordered pair exceed the boundaries specified in the COLR.

The requirement that the steam generator temperature be ~ the PCS temperature when forced circulation is initiated in the PCS ensures that an energy addition caused by heat transferred from the secondary system to the PCS will not occur. This requirement applies only to the initiation of forced circulation (the start of the first primary coolant pump) when the PCS cold leg temperature is< 430°F. However, analysis (Reference 6) shows that under limited conditions when the Shutdown Cooling System is isolated from the PCS, forced circulation may be initiated when the steam generator temperature is higher than the PCS cold leg temperature.

References (1) Updated FSAR, Section 14.3.2.

(2) Updated FSAR, Section 4.3.7.

(3) Del et ed§M§:il~llitiQ§iJii~ti!iiB§Jfi}ii§il!ignili!]lii:ffi~i~Jii§ii]g@~]i (4) EMF 92 178 Revision 3 Section 15.0.7.1 IMBt~lti9:1~::~:t:B.:@¥:1:§:1::9r,:::::::g:i:;:::::1:~¢,~:]::~i:::::::1:§::~::9::~::~*:1:m (5) ANF-90-078 (6) Consumers Power Company Engineering Analysis EA-A-NL-89-14-1 3-3 Amendment No. 3+, 5t, H-7-, tt8, Bt, t34, B-7-, 43-, tse, 59, +&g, 7-t,

ATTACHMENT 3 CONSUMERS POWER COMPANY PALISADES PLANT DOCKET 50-255 TECHNICAL SPECIFICATIONS CHANGE REQUEST PRIMARY COOLANT SYSTEM FLOW Standard Review Plan Events Reanalyzed with Revised Reactor Vessel Flow Rate 1 Page

Standard Review Plan Events Reanalyzed or Dispositioned with

. Revised Reactor Vessel Flow Rate 4.4 Thermal and Hydraulic Design

• Thermal-Hydraulic Compatibility

• Fuel Centerline Melt

• Setpoints 6.2.1.3 Mass and Energy Release Analysis for Postulated Loss of Coolant Accidents 6.2.1.4 Mass and Energy Release Analysis for Postulated Secondary System Pipe Ruptures 15 .1. 2 Increase in Steam Flow 15 .1. 5 Steam System Piping Failures Inside and Outside of Containment

• 15.3.1 Loss of Forced Reactor Coolant Flow 15.3.3 Reactor Coolant Pump Rotor Seizure 15.4.1 Uncontrolled Control Bank Withdrawal from Subcritical or Low Power 15.4.2 Uncontrolled Control Bank Withdrawal at Power 15.4.3 Control Rod Misoperation

• Dropped Rod

• Dropped Bank

• Single Rod Withdrawal 15.4.8 Control Rod Ejection 15.6.l Inadvertent Opening of a PWR Pressurizer Pressure Relief Valve 15.6.3 Radiological Consequences of a Steam Generator Tube Rupture 15.6.5 Loss of Coolant Accidents