ML17264B102

Forwards Responses to 970331 RAI Re Proposed Mod of Ginna Spent Fuel Storage Pool

ML17264B102
Person / Time
Site:	Ginna
Issue date:	11/11/1997
From:	Mecredy R ROCHESTER GAS & ELECTRIC CORP.
To:	Vissing G NRC (Affiliation Not Assigned), NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
TAC-M95759, NUDOCS 9711190115
Download: ML17264B102 (23)

Text

CATEGORY 1 REGULATORY INFORMATION DISTRIBUTIOASYSTEM (RIDE)

I ACCESSION NBR:9711190115 DOC.DATE: 97/11/11 NOTARIZED: YES FACIL:50-244 Robert Emmet Ginna Nuclear Plant, Unit 1, Rochester G

AUTH.NAME

'UTHOR AFFILIATION MECREDY,R.C.

Rochester Gas

& Electric Corp.

RECIP.NAME RECIPIENT AFFILIATION VISSING,G.S.

DOCKET ¹ 05000244

SUBJECT:

Forwards responses to 970331 RAX re proposed mod of Ginna spent fuel storage pool.

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ANn ROCHESTER GASANDELECTRIC CORPOMON

~ 89 EASTAVENUE, ROCHESTER, N. Y M&f9-0001 AREA CODE716 546-27M ROBERT C. MECREDY Vice presirrenl Nudeor Operations November 11, 1997 U.S. Nuclear Regulatory Commission Document Control Desk Attn:

Guy S. Vissing Project Directorate I-1 Washington, D.C.

20555

Subject:

Response

to, Request for Additional Information Spent Fuel Pool (SFP) Modifications - SFP Cooling Concerns (TAC No. M95759)

R.E.

Ginna Nuclear Power Plant Docket No. 50-244 Ref. (1):

Letter from G. S. Vissing (NRC) to R.

C. Mecredy (RG&E),

Subject:

Request for Additional Information Spent Fuel Pool (SFP) Modifications SFP Cooling Concerns (TAC No.

M95759), dated September 9,

1997.

Dear Mr. Vissing:

By Reference 1,

the NRC staff requested additional information regarding the proposed Modification of the Ginna Spent Fuel Storage Pool dated March 31r 1997 'nclosed are responses to each of the questions submitted by the NRC staff.

Very truly yours, Robert C. Mecr dy JPO Subscribed and sworn to before me on this 11th'ay of November, 1997 Notary Public MARIE C. ViLLENEUVE Notary

Public, State of Nevà York Monroe County Commission Expires October 31, 192 97iii90ii5 97iiiig PDR ADQCK 05000244 P

PDR II!!Ill!!III!I!ill!!ill!!ill!i!ill!!!!I!

xc: Mr. Guy S. Vissing (Mail Stop 14B2)

Senior Project Manager Project, Directorate I-1 Washington@

D ~ C ~

20555 U.S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406 Ginna Senior Resident Inspector Mr. Paul D. Eddy State of New York Department of Public Service 3 Empire State Plaza, Tenth Ploor

Albany, NY 12223-1350

U. S. NRC G. S. Vissing A-1 November 11, 1997 uestion No. 1.:

8'ith regard to the decay heat loads resultingfrom the proposed spent fiielpool (SFP) capacity expansion, Table 5.5-1 ofthe SFP Re-racking Licensing Report should be revised to include the decay heat generation rate for each batch ofthe spent fiielassemblies (Sos) storedin the SFP.

~Res ense:

See attached a revised Table 5.5-1, Ginna Spent Fuel Pool Inventory (Actual &Projected).

A few minor changes have been made to update this information since the Licensing Report was submitted on March 31, 1997.

These changes have no e6ect on the required capacity ofthe SFP cooling system.

U. S. NRC

6. S. Vissing A-2 November 11, 1997 Table 5.5-1 Ginna Spent Fuel Pool Inventory (Actual &Projected), REV. 1 Discharge Date 10/1/72 1/1/74 3/11/75 1/29/76 4/15/77 3/25/78 2/9/79 3/29/80 4/18/81 1/26/82 3/27/83 3/3/84 3/2/85 2/7/86 2/6/87 2/10/88 3/17/89 3/23/90 3/22/91 3/27/92 3/12/93 3/4/94 3/26/95 4/1/96 10/20/97 3/7/99 Average Burnup D/M 19750 25135 24054 25048 28831 28579 29429 30721 31258 32281 35200 36714 37342 39119 39421 40281 38118 36995 39473 40057 44705 42397 41518 40674 39060 Pro:55000 Number of Assemblies 81'2 24 37 41 41 40 36 15 19 21 28 29 31 32 33 36 37 29 37 29 27 37 41 41 44 Heat Load on 9/18/2029 TU/hr 3.69E+04 5.58E+03 1.14E+04 1.78E+04 2.02E+04 2.05E+04 2.03E+04 3.19E+04 1.35E+04 1.73E+04 1.95E+04 2.63E+04 2.77E+04 3.01E+04 3.15E+04 3.31E+04 3.67E+04 3.84E+04 3.06E+04 3.96E+04 3.16E+04 2.99E+04 4.17E+04 4.70E+04 6.77E+04 7.46E+04 Days of Decay to 9/18/2029 20806 20349 19915 19591 19149 18805 18484 18070 17685 17402 16977 16635 16271 15929 15565 15196 14795 14424 14060 13689 13339 12982 12595 12223 11656 11153 a)

Ofthe original 81 fuel assemblies discharged in 1972, 70 remain as intact fuel assemblies, but the fuel rods from 11 intact fuel assemblies were extracted and stored in 8 consolidated rod canisters (the consolidated hardware was stored in two additional canisters).

U. S. NRC G.'S. Vissing A-3 November 11, 1997 Table 5.5-1 Ginna Spent Fuel Pool Inventory (Actual Ch Projected), REV. 1 Continued Discharge Date Average Number of Burnup Assemblies D/MTU Heat Load on 9/18/2029 TU/hr Days ofDecay to 9/18/2029 9/15/00 3/17/02 9/16/03 3/15/05 9/21/06 3/19/08 9/18/09 3/15/11 9/15/12 3/15/14 9/15/15 3/15/17 9/15/18 3/15/20 9/15/21 3/15/23 9/15/24 3/15/26 9/15/27 3/15/29 9/18/29 TBD Total Pro':55000 Pro':55000 Pro':55000 Pro':55000 Pro':55000 Pro':55000 Pro':55000 Pro':55000 Pro':55000 Pro':55000 Pro':55000 Pro:55000 Pro':55000 Pro':55000 Pro':55000 Pro':55000 Pro':55000 Pro':55000 Pro:55000 Pro':55000 44 44 44 44 44 44 44 44 44 44 44 44 44 44 44 44 44 44 44 44 121 1879 7.68E+04 7.90E+04 8.13E+04 8.37E+04 8.63E+04 8.90E+04 9.18E+04 9.48E+04 9.81E+04 1.02E+05 1.06E+05 1.11E+05 1.17E+05 1.24E+05 1.36E+05 1.54E+05 1.87E+05 2.60E+05 4.53E+05 1.27E+06 10595 10047 9499 8953 8398 7853 7305 6762 6212 5666 5117 4570 4021 3474 2925 2379 1829 1283 734 187

U. S. NRC G. S. Vissing A-4 November 11, 1997 uestion No. 2.:

In Section 5. 7 ofthe SFP Re-racking Licensing Report, Ginna states that the technical specification (TS) limitfor the SFP water is 150'F whichis achieved with the present SFP cooling system.

The heat removal capability ofthe SFP cooling system heat exchangers varies as the temperature ofLake Ontario water varies.

Therefore, the duration ofreactor shutdown required prior to any SFAs discharged to ensure that the SFP water temperature does not exceed its 150'F limitis afunction ofLake Ontario water temperature.

For afullcore off-load

scenario, the followingsummarizes the reactor shutdown times required prior to the discharge of any SFAfor three lake temperatures (40'F, 60'F, and 80'F) to prevent the SFP waterfrom exceeding the 150'F limit:

Lake Water Temperature, 'F SFAs In Reactor Decay Time Required, Hrs.

40 60 80 100 132 280 Have these restrictions requiredfor SFAs to decay in the reactor prior to the discharge ofany SFA beenincorporatedin the Ginna TS? Ifnot, provide detailedjustifications fornot having these restrictionsimposedin the TS.

Also, provide the decay heat loads in the SFP and the corresponding calculated SFP water temperatures as afunction ofreactor shutdown timefor each ofthe above cases.

~Res oose:

Section 5 ofthe SFP Re-racking Licensing Report is in error when it states that the technical specification limitfor the SFP water is 150'F. This limitis actually in the technical requirements manual (TRM), which is a document formatted similar to the Ginna Station Improved Technical Specifications, but is actually an extension ofthe UFSAR (i.e., changes to the TRM are performed under 10CFR50.59).

The SFP water limitis specified in the TRM, since 10CFR50.36 does not require this to be speciFied within the technical specifications (see also NUREG-1431, Improved Standard Technical Specifications for Westinghouse Plants).

The in-reactor decay time has been misinterpreted.

This is not the time required before the first SFA can be placed in the SFP but a time used for calculational purposes that represents the heat load associated with all the SFAs being instantaneously placed in the SFP.

SFAs may be placed in the SFP before this time but the total reload or ofF-load cannot be placed in the SFP until this time has elapsed.

The heat removal evaluations ofthe SFP cooling system are based on two primary parameters.

f U. S. NRC G: S. Vissing A-5 November 11, 1997 The first is the lake temperature, since this provides the ultimate heat sink for the SFP, and the second is the reactor decay time, since this provides the heat load within the pool. RGB proposes to add these two parameters to the TRM similar to the 150'F SFP water temperature.

Placement ofthese parameters within the TRM provides a very clear and concise operating limit that is evident to all plant personnel, including operations.

Changes to these two parameters can still be made by RGEcE based on fuel cycle inputs, but only using 10CFR50.59.

The NRC would be notified ofthese changes via 10CFR50.71 (i.e., UFSAR update process).

The decay heat load vs. time used for the full core ofF-load for each ofthe Lake Ontario water temperatures is shown in Figures 2-1, 2-2, and 2-3. The increase in SFP heat load above the background value in the figures corresponds to the placement ofthe full core off-load in the SFP after the required in-reactor decay time.

The SFP temperature vs. time for a full core ofF-load scenario at each ofthe lake water temperatures is provided in Figures 2-4, 2-5, and 2-6. These SFP bulk temperatures were calculated for an instantaneous placement ofthe full core in the SFP, neglecting the thermal inertia ofthe SFP and using design conditions for fouling and tube plugging for the SFP heat exchangers.

U. S. NRC G. S. Vissing A-6 November 11, 1997 25 20

~ 15 o

10 Oe C4 200 400 600 800 1000 1200 Time After Reactor Shutdown (hours)

FIGURE 2-1 SFP HEAT LOAD - FULL CORE DISCHARGE 40 F LAKEWATER TEMPERATURE 25 20 g

15 O

10 g-M 5

200 400 600 800 Time After Reactor Shutdotrn (hours) 1000

- 1200 FIGURE 2-2 SFP HEAT LOAD - FULL CORE DISCHARGE 60 F LAKEWATER TEMPERATURE

r

~

r U. S. NRC G.'. Vissing A-7 November 11, 1997 20 15 10 o

~4 tu CLr Orro 200 doe 600 800 1000 1200 Tlmo AftorRoostor Shutdooru (hours)

FIGURE 2D 6FP HEAT LOAD-FULLCORE DISCHARGE 80 F LAKEWATERTEMPERATURE 200 150 100 ca 50 200 400 600 800 1000 1200 Tttne After Reactor Shutdown (hours)

FIGURE 2-4 SFP HEAT LOAD-FULL CORE OFFLOAD 40 F LAKEWATER TEMPERATURE

t U. S. NRC G'. S. Vissing A-8 November 11, 1997 200 150 oI 100 I4 ore 50 200 400 600 800 1000 1200 Thuo After Reactor 6hutdown (hours)

FICURE 2-5 SFP TEMPERATURE - FULL CORE OFFLOAD 60 F LAKEWATER TEMPERATURE 200 150 o

" 100 Ore 50 200 400 600 800 1000 1200 Titus After Reactor Shutdown (hourS)

FIGURE 2-6 SFP TEMPERATURE - FULL CORE OFFLOAD 80 F LAKEWATER TEMPERATURE

U. S. NRC G. S. Vissing A-9 November 11, 1997 For the normal (routine refueling with I/3 core discharged) discharge scenario as discussed in Section 5.5.2.1 ofthe SFP Re-racking Licensing Report, provide the decay heat loads in the SFP and the corresponding calculated SFP water temperatures as afimction ofreactor shutdown time. Also, indicate the lake water temperature which was used in the analysis.

~Res ense:

The SFP temperature limitis the same for the normal discharge and the fullcore ofF-load, 180'F.

Since the heat load associated with the full core ofF-load is significantly greater than the normal discharge, calculations have only been provided for the bounding case:

the full core ofF-load.

See the response to Question No. 5 for the values used in the bounding analysis.

The single batch core o6-'load can be performed after the minimum 100-hour shutdown time limit associated with the radiological requirement (postulated fuel-handling accident).

The limiting design SFP decay heat load at 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> for the single batch ofF-load and the design heat removal capability ofthe "8" SFP cooling loop with design conditions for fouling and tube plugging is summarized below for lake water temperatures of40'F, 60'F, and 80'F:

Lake Water Temperature

('F) 40 SFP "B" Heat Exch.

Capacity (MBtu/hr) 24.6 Decay Heat Load (MBtu/hr) 11.3 Delay Time Required for the Radiological Requirement (hours) 100 60 20.4 11.3 100 80 16.0 11.3 100 This limitingcase was very conservatively calculated assuming the removal of44 fuel assemblies being operated at 1.35 times the core average, in addition to a background heat load of3.7 MBtu/hrofpreviously discharged fuel.

This limitingdesign decay heat load vs. time used for a 1/3 core oF-load is shown in Figure 3-1.

The increase in SFP heat load above the background value 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> aAer reactor shutdown in the figure corresponds to the placement ofthe 1/3 core ofF-load into the spent fuel pool.

U. S. NRC G. S. Vissing A-10 November 11, 1997 The corresponding SFP temperature vs. time for a 1/3 core off-load at each ofthe Lake Ontario water temperatures are provided in Figures 3-2, 3-3, and 3-4. These SFP bulk temperatures were calculated for an instantaneous placement ofthe 1/3 core in the SFP after the minimum required 100-hour decay time. The thermal inertia ofthe SFP was neglected and design conditions for fouling and tube plugging were used for the SFP heat exchangers.

The actual decay heat associated with a normal 1/3 core oF-load is significantly less than the limitingcase analyzed.

The decay heat is calculated using a methodology similar to the full core off-load methodology with more realistic assumptions concerning burnup ofthe ofF-loaded assemblies, background decay heat load, and number ofdischarged assemblies to ensure 100%

cooling system backup is available prior to placing the spent fuel into the spent fuel pool.

Because the decay heat load from the 1/3 core is so much less than the design limiting case analyzed, the spent fuel pool temperature willnever approach the 150'F limit, using any single one ofthe three spent fuel pool cooling subsystems.

The realistic calculation for the 1997 reload is summarized below:

Lake Water Temperature

('F)-

40 SFP CCATS Heat Exch.

Capacity (MBtu/hr) 14.5 Decay Heat Load (MBtu/hr) 9.2 Delay time Required for the Radiological Requirement (hours) 100 60 12.0 9.2 100 80 9.3 9.2 100

U. S. NRC G'. S. Vissing A-11 November 11, 1997 10 I

8 m

8'o O

4 nI Q1 200 400 600 800 Time Alter Reactor Shutdown (hours) 1000 1200" FIGURE 3-1 SPF HEAT LOAD-NORMALBATCH OFFLOAD (40 FI 60 F 8s 80 F LAKEWATER TEMPERATURES) 200 150 I.

100 50 200 400 600 800 Tlme Alter Shutdown (hours) 1000 1200 FIGURE 3-2 SPF TEMPERATURE NORMALBATCHOFFLOAD 80o F LAKEWATER TEMPERATURE

4 U. S. NRC G. S. Vissing A-12 November 11, 1997 150 100 o

CI SO Ch 2OD 400 600 800 1000 1200 Titus Attar Shutdown (bours)

FIGURE 3-3 SPF TEMPERATURE NORMALBATCH OFFLOAD 60 F LAKEWATER TEMPERATURE 100

~O 4

SO Qe 8

De co 200 400 600 800 1000 1200 Titna Attar Shutdown (hours)

FIGURE 3-4 SPF TEMPERATURE NORMALBATCH OFFLOAD 40 F LAKEWATER TEMPERATURE

U. S. NRC G. S'. Vissing A-13 November 11, 1997 In an event ofa complete loss ofthe SFP cooling system (i.e., resultingfrom a station blackout event, a seismic event, etc), with the assumption that 1879 (afiillcore off-loadscenario with a fiillinventory ofSFAs) SFAs are stored in the pool and the pool temperature is 150'F, provide an analysis to show the time requiredfor the SFP to boil. Information to be provided should include: input parameters (i.e., the reactor shutdown time required prior to the SFA discharge, etc) used to calculate the decay heat load; SFP boilingoffrate; methods to replenish the SFP water; and sources ofmakeup water.

~Res ense:

SRP 9.1.3,Section III.l.d,requires evaluation ofthe abnormal maximum heat load (i.e., full core off-load) to ensure the SFP water remains below boiling and the liquid level is maintained without consideration ofa single active failure. For Ginna Station, the SFP seismic design has only been evaluated up to a SFP temperature of 180'F.

Therefore, the maximum temperature under abnormal conditions is 180'F and not boiling (212'F).

The analysis presented in Section 5.10 ofthe SFP Re-Racking Report lists the time it takes for the SFP to heat up from 150'F to 180'F.

The worst case scenario listed is 2.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />.

Since no single active failure must be considered, SFP Cooling Train B can be used.

Even though not required by the SRP, the use of SFP Cooling Train A (original system) and the skid-mounted system are a second alternative. Both the preferred and alternative method can be accomplished by loading the specified SFP cooling system on the emergency diesel generators within the 2.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />.

Therefore, the SRP requirement is met. Also, since the SFP remains below 180'F (and below boiling), there is no assumed SFP boil-offrate and no required makeup capability. The normal makeup methods can accommodate the evaporative losses.

However, for the purpose ofanswering this hypothetical question, the increase in the SFP bulk temperature with time (the heat up'rate) has been determined, assuming a complete loss ofthe heat removal system.

The analysis conservatively does not take credit for conduction in the pool walls or floor, evaporative cooling or convective cooling to the ambient air. The thermal inertia ofthe SFP is calculated by summing the individual (pool water, rack steel, and fuel assembly materials) heat capacities.

In the case ofa complete failure ofthe SFP heat removal system, the heat up rate, the time to reach 212'F, and the rate ofevaporation have been calculated based on the heat load for the full core off-load scenario and Lake Ontario water temperatures of40'F, 60'F, and 80'F. The values determined are summarized below:

U. S. NRC G. S. Vissing A-14 November 11, 1997 SFP Configuration: Full Core OfF-Load, 1879 SFAs Lake Water Temperature

('F) 40 Heat Load (MBtu/hr) 21.7 Delay Time Required for the 150'F Tech.

Spec.

LimitTemp.

(hours) 100 Time to Boil 150'F~212'F (hours) 5.7 Evaporation Rate (gpm) 47.0 60 20.4 132 6.1 44.0 80 16.0 280 7.7 35.0 Makeup System:

The normal makeup water source is the Refueling Water Storage Tank. It contains in excess of 70,000 gallons ofborated water, once the refueling cavity is filled. The maximum makeup rate of 60 gpm can be made available in less than 15 minutes.

As an alternative, the CVCS hold-up tanks provide an alternate source ofwater at 50 gpm, which could be made available in approximately 15 minutes.

Other makeup sources are the reactor makeup water tank or monitor tanks, which could supply water at 40 gpm and could be available within 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br />.

The makeup rate from the primary source and one ofthe alternate sources exceeds the boil-ofF rate of47 gpm (40'F lake water temperature) and 44 gpm (60'F lake water temperature).

The makeup water rate from all sources exceeds the 35 gpm boil-ofFrate for the 80'F lake water temperature.

U. S. NRC G: S. Vissing A-15 November 11, 1997 uestion No. 5.:

In Section 5.10 ofthe SFP Re-racking Licensing Report, Ginna states that in the event ofa complete loss ofthe SFP cooling system, the original Poop 1) SFP cooling system can be made operationalin 45 minutes and that an additional 5.3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> would be available for repair or to place the skid-mounted unit Poop 3) into operation before the pool temperature reaches 18'.

Provide the followinginformation:

detailed discussion to show how the above-cited 45 minuteswere derived, detailedj ustifications (including equipment availability, readiness, etc) to show that 5.3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> willbe adequate forrepair or to place the skid-mounted unitinto operation, and detailed discussion to show how longitwilltake to make the original SFP cooling system operational during an event ofa complete loss ofthe SFP cooling system, resultingfrom a station blackout event, a seismic event, etc.

~Ree ense:

The SER for the Ginna SFP cooling system (Ref. 1) required a 100% backup cooling capability.

For a nor'mal reload, 1/3 core, 100% backup cooling is provided by the original (loop 1) SFP cooling system. For a full core unload, 100% backup cooling is provided by the original and the skid-mounted units operating in parallel. The single active failure is assumed to be a component in the SFP cooling system.

The following steps are necessary to activate the original system:

1.

Close one manual 4" valve isolating the lower suction from the SFP to the "B"(loop 2)

SFP cooling system.

(5 min) 2.

Open one manual 6" suction valve upstream ofthe pump.

(5 min) 3.

Open one manual 4" valve to allow SFP water to be discharged from the heat exchanger back to the SFP.

(5 min) 5.

Close one 6" valve at the discharge ofthe "B"pump.

(5 min) 6.

Open one 2" valve in the purification line. (2 min) 7.

Close one 2" valve isolating the "B"system purification line. (2 min) 8.

Operate several small instrumentation valves.

(2 min)

~

~

U. S. NRC G. S. Vissing A-16 November 11, 1997 9.

Start the SFP pump from a local on/offswitch.

Since service water is continually supplied to the loop 1 heat exchanger, no valve manipulations are required.

The accident analysis ofa loss ofoffsite power assumes that power is restored to the vital buses within 12.75 sec.

Since the SFP pump is powered offa vital bus, there is almost no additional time to add to the above times followingthe loss ofoffsite power.

As shown above, the operations necessary to place the original SFP cooling system in service is less than 45 minutes.

The skid-mounted system is only necessary during a full core unload. Prior to a fullcore unload, the skid-mounted system is placed in position, hoses connected, and leak checked.

The following operations would be necessary to activate the skid-mounted system:

Open one manual 6" valve to admit service water to the heat exchanger.

2.

Open one manual 6" valve to allow service water to be discharged from the heat exchanger.

Open one manual 6" suction valve upstream ofthe pump.

4.

Open one manual 4" valve to allow SFP water to be discharged from the heat exchanger back to the SFP.

Open one 4" lower suction valve.

Start the skid-mounted pump using local on/offswitch.

As discussed earlier, the accident analysis ofa loss ofoffsite power assumes that power is restored to the vital buses within 12.75 sec.

Since the skid-mounted pump is powered offa vital bus, there is almost no additional time to add to the above times followingthe loss ofoffsite power.

The operations described above can be accomplished well within the additional 5.3 hr. required to heat up to 180'F.

U. S. NRC G. S. Vissing A-17 November 11, 1997 The original analysis assumed the heat exchanger and pump was staged and connected prior to starting the system.

Considerable time can be saved by having the equipment pre-positioned and connected.

As described above in the response to Question 4., the SRP does not require assumption ofa single active failure. Therefore, SFP Cooling Train B would be available. Re-initiating SFP Cooling Train B following a loss ofoffsite power is accomplished by locally operating the on/off switch, since the pump is supplied from a vital bus.

The vital bus would be re-powered following a loss ofoffsite power by the time the operator actuated the on/offswitch.

This case is bounded by the case presented in Section 5.10 ofthe SFP Re-rack Licensing Report.

The TRMwillbe modified to ensure 100% backup for all SFP cooling scenarios, along with lake water temperature, in-reactor decay times, and associated SFP heat loads.

References:

1.

Letter from D. M. Crutchfield (NRC) to J. E. Meier (RGEcE),. dated November 3, 1981;

SUBJECT:

SPENT FUEL POOL COOLING SYSTEM MODIFICATIONS(GINNA).

Sss 4S

+%0 v

s U. S. NRC G. S. Vissing A-18 November 11, 1997 uestion No. 6.:

Discuss the procedures to be utilized by the Ginna staffto monitor and control the SFP water temperature and decay heat load so as to remain within the design basis limitingvalues for routine refueling and planned or unplanned fullcore off-load events.

Include discussion ofthe location ofneededinstrumentation, means ofmonitoringit, andintegration ofoperation staff activities with engineering staffacti vities in order to implement the procedure(s).

R~es ense:

As described in Section 2.0, RGB proposes to add requirements to the TRMwith respect to lake water temperatures and reactor decay time. These limits, in combination with a maximum SFP temperature of 150'F, willensure that all assumptions ofthe SFP heat load analyses remain bounding.

Included with these two new requirements willbe appropriate surveillances (i.e.,

verification ofminimum reactor decay time prior to moving fuel to the SFP and periodic verification ofthe lake water temperature).

The verification ofminimum reactor decay time is an administrative function based on time since MODE 2 was exited. Periodic verification oflake water temperature willbe accomplished consistent with current technical specification Surveillance Requirement SR 3.7.8.1 (verification ofscreenhouse water temperature to SW suction every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />).

Verification that the SFP water temperature is < 150'F willcontinue to be once every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> at all times, per TRM Surveillance Requirement TSR 3.9.2.3.

Since the TRM is controlled by Engineering but implemented by Operations, necessary integration is maintained.

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