ML20056A184

Forwards Revised Methodology for Achieving Alternate Ac for Plant,Per 900720 Telcon

ML20056A184
Person / Time
Site:	Beaver Valley
Issue date:	07/27/1990
From:	Sieber J DUQUESNE LIGHT CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9008060059
Download: ML20056A184 (8)

Text

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P. .4w n.o, w m m (Jt4 JULY 27, 1990  !

i U. S. Nuclear Regulatory Commisalon Attnt Document Control Desk i Washington, DC 20555

Reference:

Beaver Valley Power Station, Unit No. 1 and No. 2 '

, BV-1 Docket No. 50-334, License No. DPR-66 BV-2 Docket No. 50-412, License No. NPF-73 SB0 - Alternate AC Load Management Gentlement By letter dated June 27, 1990, we provided a supplemental response to Station Blackout (SBO) relative to our Alternate AC (AAC) load management methodology. Based on our telecon of July 20, 1990, with the staff reviewers, we were requested to revise the AAC load management tables of our enclosure to demonstrate the design capability of our existing Class lE emergency diesel generators as an AAC source for our dual unit i site. For analysis purposes, the following loads have been added to Table it Turbine Bearing 011 Lift Pump Turbine Generator Bearing Lube Oil Pump Turbine Turning Gear Drive ,

Residual Heat Relcacc (RHR) Pump '

l The charging pump at the SBo unit, identified as a discretionary load, has been dropped from Table 1, and will be procedurally addressed. As stated in our March 30, 1990 submittal, the expected rates of reactor coolant system inventory +

loss of 25 gpm per pump under SB0 conditions will not result in core uncovery during a SBo of 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, our concern for the potential inconsistency between. the design capability documented in the tables and our operating procedures was acknowledged by the staff. The reviewers re-iterated their position that

• discretionary loads may be procedurally addressed to allow for operator flexibility via load management. We understand that the '

safety evaluation report will acknowledge the provision for  !

procedurally addressing discretionary loads, as noted above.

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Be;vor Vallcy P:wcr StOtien, Unit Noa. 1 & 2  ;

. Docket No. 50-334, License No. DPR-66 Docket No. 50-412, License No. NPF-73 SB0 - Alternate AC Load Management Page 2 Enclosure 1 "AAC Load Management Scheme for Beaver Valley" '

provides the revised methodology for achieving AAC for both Beaver Valley Unit 1 and Unit 2. The proposed load management scheme ensures the non-blacked out unit is brought to and maintained in a safe shutdown condition which meets the SBo regulatory requirements. Differences in the assumptions for loss-of-offsite power loads from those currently specified in the UFSAR have been identified with justifications provided in the enclosure.

If there are any questions on this matter, please contact my office.

I l Very truly yours, J. D. Sieber Vice President Nuclear Group cc: Dr. T. Murley, Director of Office of NRR Mr. J. Beall. Sr. Resident Inspector Mr. T. T. Marti ,i'PC Region I Administrator Mr. A. W. DeAgazio, Project Manager Mr. R. Saunders (VEPCO)

NUMARC l

1

4 ENCLOSURE I Page 1 1

ALTERNATE AC LOAD MANAGEMENT SCHEME FOR BEAVER VALLEY i

The revised Alternate AC (AAC) load management scheme is summarized in this enclosure. The AAC power system is adequately sized to carry the required shutdown loads for the required coping duration maintaining voltage and frequency within limits e consistent with the established industry standards. Also, the loading arrangement will not degrade the performance of any shut down systems or components.

Loads Available During The First Hour During the first hour of the event, all applicable loads identified in the FSAR table may be powered. This includes all loads that are automatically loaded onto the diesel generators as indicated in Table 8.5-1 of the FSAR.

Loads Available After One Hour and Before Four Hours After the first hour, a degree of load management is necessary to ensure adequate Alternate AC power is available to the blacked out unit. These loads fall into three categories (a) loads that are not generally powered within the expected duration of the station blackout, (b) loads that are not required to ensure safe shutdown capability, and (c) loads that do not have a safety function.

a. Loads that are not cenerally nowered within the exoected duration of the station blackout It is important to note that some safe shutdown loads are only normally needed during the first hour of the transient, or considerably after four hours. These loads include motor operated valves, and the spent fuel pool cooling system.

Power for motor operated valves, will only be needed during the first ten minutes to realign safety systems. Since these components are not normally energized after the first hour of the event, they do not need to be powered after the first hour.

The spent fuel pool cooling pumps will not need to be powered until after the coping period for a loss of off site power.

Thus, it is not necessary to consider this load during the .

1 four hour duration of a station blackout.

l 1

i

ENCLOSURE I

- Page 2 j l

ALTERNATE AC LOAD MANAGEMENT SCHEME FOR BEAVER VALLEY l

The Leak Collection exhaust fans, although automatically loaded on the EDG for a loss-of-offsite powe.r event, are primarily to prevent radioactive leakage from the containment and contiguous areas following a DBA. The system provides ventilation to the Aux FW pump room which whs analyzed for a ,

loss of ventilation under SBO criteria. Therefore, this load is not needed for normal safe shutdown following a loss-of-offsite power event with no concurrent failure or DBA type events.

b. Loads that are not reauired to ensure safe shutdown capability Several loads are not needed for normal safe shutdown following a loss of off site power. These include the containment . air recirculation fans, and the containment instrument air compressors. The unavailability of these systems during this period will not reduce the information available to the operators to monitor the safety related conditions of the plant, nor will it impair or damage the non-blacked out (NBO) unit in any way, b.1 Containment ventilation cooling water is noi safety related at Beaver Valley. Thus, the containment recirculation fans'would not serve their cooling function and would only add to the- heat generation. This

, condition has been analyzed and verified during plant l operation. Containment temperatures have been shown '

j to not increase beyond 110*F during the first four hours of the event. This temperature is considerably below the EQ operability limit of 135'F.

b.2 Similarly, cooling water for the containment instrument air compressor is not safety related, and consequently is normally unavailable during a loss of off-site power.

For this reason, the compressor must be disabled since operation without cooling results in an electrical trip of the component. Existing plant procedures for coping with a LOOP event direct operators to disable the compressor for a loss of cooling water resulting from the loss of off-site power. This system is not required to.

ensure safe shutdown capability.

I LER 84-07 Loss of Containment Cooling

ENCLOSURE I Page 3 l

l ALTERHATE AC LOAD MANAGEMENT SCHEME FOR BEAVER VALLEY I Lg&Jvailable_4tter Four Hours The station blackout rule only requires Alternate AC power to be I provided for the etation's required coping duration. Thus, after l four hours, Unit i no longer needs to supply AAC power to Unit 2. i However, as discussed above, the proposed loading arrangement is sufflcient to maintain the station in a safe condition for an extended duration beyond four hours.

EQEJsy.g);&jggnt and Athodoloav Procedures (EOP's) will be developed to allow for discretionary loads for operator flexibility of load management dependent on sufficient EDG capccity. The addition of a high-head charging pump to the blacked-out unit would be one such example.

Both Beaver Va ,ey units are equipped with 100% capacity turbine driven AFW pur i d . Irrespective of the turbine driven AFW pump, sufficient deLign capability is available to power the motor-driven AFW pump at the NBO unit during this event. (See Table 1)

Summary and Conq1usion The load management scheme discussed above ensures the NBO unit is ,

brought to and maintained in a safe shutdown condition for an extended period well beyond four hours. No component is permanently disabled or in any way degraded. In fact, load management is needed to ensure long term operability of equipment. On this basis, we find that this arrangement meets the current SBO requirements.

l l

t.evised: July 27, 1990

• TAgLE 1 .

i Alternate AC Loed Management $cheme for lesver Valley i (Total Londe on Unit i EDG) i UNIT 1 UNIT 2 COMPONENT LOADS (kW) LOAD $ (kW)

NIO Unit 30 Unit Remarka 0 to i hour to After 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> to i hour 4 heure 4 houra 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />

> Charging *NI Need Safety 442.0 442.0 442.0

! Infection Puma '

tiver Water Pune 338.0 338.0 338.0 (+1 + tross tle RWS Steam tenerator AFW Pune 302.0 302.0 302.0 RER Puma

• O 213.6 218.0

• 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> delav PrtCary plent Component 221.0 221.0 221.0 toolina Water Puno Turbine 8 earing oit 13.0 13.0 13.0 Lift Pune Motor ODerated Valvon 53.0 0.0 0.0 See section a i

E0ergency Diesel 28.0 28.0 28.0 Ausillaries Turbine Generator 39.0 39.0 39.0 Liarina Lube 011 Puno Turbine Turning Gear 39.0 39.0 39.0 trive Pressurizer Neaters ** 0.0 270.0. 270.0 ** 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> delav Borfe Aeld Transfer Puen 13.0 13.0 13.0 sorte Acid Tank Meaters 15.0 15.0 15.0 Batterv thernera 38.0 38.0 38.0 14.6 E00rgency Llehting 5.0 5.0 5.0 Buontemental Ecorgency Llehting 28.0 28.0 28.0 Sunntemental Containment Air 283.0 0.0 0.0 See Section b.1 teelreulation Fans Control Room Air 48.0 48.0 45.0 sunetv Fans, Control Room Air Return 25.0 25.0 25.0 fans Control Room AC 61.0 61.0 61.0 compressors Centrol Room AC 4.0 4.0 4.0 Condenser Circulating Pumos Lock Cottection Eshaust 115.0 0 0 See section a Fana Safoguards Area lump 4.0 4.0 4.0 Puen Ecorgency Swgr & 8.0 8.0 8.0 gottery Room Eshaust Fan Ecorgency Swgr & 13.0 13.0 13.0 settery' Room Suppty Fan Fuel Pool Coolina Puno 17.0 0.0 17.0 See Section a ceintermittent Load; Pressurizer heaters to be de-energized when starting discretionary Load (charging pump) et SV+2. To be procedurally addressed.

I Rovised: July 27, 1970 l

e TABLE 1 (Cont.)

Alternate AC Loed Management Scheme For Beaver Valley (1 stat Lends on Unit 1 EDE)

Uutf 1 UNIT 2 ,

COMPOWENT LOADS (kW) LOADS (kW) use Unit so Unit temarka 0 to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> to After 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> to

_ 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> 4 heura 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> l

control med cooling 81.0 81.0 81.0 56.0 See Fan Miscellaneous fans, 13.0 13.0 13.0 Dammers. and Pumma Niscettaneous Fans, 10.0 10.0 10.0 Dammers. and Pumma Pine Beat Tracina 60.0 60.0 60.0 Pine Beat Tracina 40.0 60.0 40.0 Vital Bus Londa 50.0 50.0 50.0 Niaceitaneous Neaters 42.0 62.0 62.0 Mlacetlaneous Neaters 12.0 12.0 12.0 Ecorgency AC 11.0 11.0 11.0 Dlatributton Panets E00rgency AC 22.0 22.0 22.0 Distribution Paneta Containment Instr. Air 17.0 0.0 0.0 See section b.2 Comoreanor Commuter Inverter 17.0 17.0 17.0 48 Volt Batterv Charmer 5.0 5.0 5.0 Additional $80 loads for to Unit Centrol Roon NVAC 27.4 Fan only ,

Unit (BV-2)

LCCd & Cooling System 49.0 l Lesses AC Dist. Tranaf.

l AC Dlat. Transf. 0.3 AC Dist. Transf. 3.1 AC Dist. Transf. 0.3 AC Dlat. Tranaf. 5.1 l Vital Bus Rect. 2-3 8.8

( Vital Bus Seet. 2-1 14.0 Bettery Room Exhaust 6.2 Fan AC Dlatr. anfr 2.9 AC Distr. anfr 2.1 TOTAL LOADE 2572.0 2575.0 2592 189.8 TOTAL LOADS Ou UNIT 1 EDO 2572.0 2764.8 2592 NOTE: Dieset generator 168 hour0.00194 days <br />0.0467 hours <br />2.777778e-4 weeks <br />6.3924e-5 months <br /> rating = 2950 kv.(Ref. UFSAR*1, Fig. 8.1 1).

l I A single CROM shroud fan is sufficient during the first four hours l

for. upper head cooling per E0Ps and engineering evaluation. i soference EN No. 22241.

.- I Revloed: July 27, 1990 .

TABLE 2 Alternate AC Loed Management $cheme For Seever Valley j (Total Lcode on Unit 2 EDC) l l

UNIT 2 UNIT 1 COMPOWENT LOADS (kW) LOADS (kW) l Neo Unit to Unit temarke >

0 to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> to After 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> to i hogr 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> 4 houra 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />  !

Chorging.NI Need safety 477.0 477.0 477.0 442 Infection Puma

! Servlee Water Pune 696.0 696.0 696.0 Stone Generator AFW 320.0 320.0 320.0 l t K2

• tua Puen

• 0 241.0 241.0

• 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> detav Primary Plant Component 316.c 316.0 316.0 Coottna Water Puen Look Colet. Fitter 150.0 150.0 150.0 Eneh. Fana EC3rg, suer. Supply 50.4 50.4 50.4 ,

Fans EOerg. Sugr. Each. 44.9 44.9 44.9 Fana Main Steam Fana 62.0 62.0 62.0 Cont. Air Reetre. Fans. 154.0 0 0 See section b.1 Lenk Bvs. Elec. Utr. 211.0 211.0 211.0 '

Press. Nesters ** 0.0 270.0 2 7J . 0 ** 1 Nour Detav (LAN Ibroud Fan 56.0 56.0 56.0 81.0 see Note i Lcod & Ctg. Sya. 49.0 49.0 49.0 Lomaea (MFNR)

AC Dlat. Transf. (f*5) 0.3 0.3 0.3 BWP Lube Water Strainer 0.5 0.5 0.5 Intake tunnly Fan 4.1 4.1 4.1 -

AC Dlat. ftansf. (E.3) 3.1 3.1 3.1 Control Re. At Unit 27.4 27.4 27.4 61.0 Refria. Cond. Unit 50.0 50.0 50.0 AC Dist. Transf. (E*9) 0.3 0.3 0.3 Etee. Neat Mfar. 2.1 2.1 2.1 Notor Operated Valves 110.6 0 0 See Section a (total)

Fuel Poet Coolina Puen 14.4 0 14.4 See Section L Cont. Bids. Air Each 25.0 25.0 25.0-and summtv Fan Chg. Pump cub. 18.0 18.0 18.0 Each. Fan AC Dist. Transf. (f.11 5.1 5.1 5.1 NCC Cub. Each. Fan 2.8 2.5 2.8 08 Fuet Oft Mfr. Puana 0.7 0.7 0.7 DS Bldg. Supply Fan 33.0 33.0 33.0 (270A)

• Os Crank Case 1.1 1.1 1.1 Vacuus Pump

• • Interalttent Lond

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