ML17258A568

Responds to Draft Safety Evaluation for SEP Topic III-4.A, Tornado Missiles.Specified 250-mph Tornado Too Conservative. Suitable Tornado Velocity to Be Included in Review of SEP Topic III-2,wind & Tornado Loadings

ML17258A568
Person / Time
Site:	Ginna
Issue date:	02/18/1982
From:	Maier J ROCHESTER GAS & ELECTRIC CORP.
To:	Crutchfield D Office of Nuclear Reactor Regulation
Shared Package
ML17258A569	List: ML17258A568 ML17258A570
References
TASK-03-02, TASK-03-04.A, TASK-3-2, TASK-3-4.A, TASK-RR NUDOCS 8202240224
Download: ML17258A568 (8)

Text

>~a-. REGULATORY ORMAT ION DISTRIBUTION "SYS ('RIDS)

ACCESSION NBR;8202240224 DOC ~ DATE: 82/02/18 NOTARI'ZED: .NO .. DOCKET FACIL:50-244 Rober.t Emmet Ginna Nuclear Plantr Uni:t 1r Rochester -G 05000244 "AUTH INANE AUTHOR AFFILIATION MAIERiJ ~ E. Rochester Gas 5 <Electric Corp ~

RECIP ~ NAt~E, RECI'PIENT AFFILIATION ORUTCHFIELDg D ~ Operatina Reactors Branch 5 SUBJEOT: Responds to dr af t safety evaluation for'SEP 'Topic III"g,'Ai, speci f ied '250-mph 'tornado too conservative 'tor.nado missiles ~

Suitable ~tornado .velociity to, be included 'in review of 'SEP Topic III"'2>wind DISTRIBUTION 'CODE: 'A0358 TITLE: SEP Topics 8 tornado loadings

)COPIES RECEIVEDeLTR

~

ENCL J,. SIZE ~, 9+5 NOTES: 1 copy.'SEP Sect ~ Ldr ~ 05000204 REC IP IENT iCOPIES RECIPIENT COPIES ID CODF/NAME LT~TR ENCL ID ~CODE/NAME L'PTR ENCL ACTION ORB 05 BC 01 7 7 INTERNALS IE 06 2 '2 NRR/DE/ADMQE 13 NRR/DE/HGEB 10 2 2 NRR/DL/ORAB 11 NRR/DL/SEPB 12 3 3 'P/ EB NRR/DSI/CSB -07 1 1 REG FILE 04 EXTERNAL: ACRS 14 10 10 LPDR 03 NRC PDR 02 1 1 NTIS 5 4

h 33 TOTAL NUMBER OF COPIES REQUIRED: LTTR ~

33 ENCL

l'

~ Ci '

Ei a

~ e~ k, p A -I w + 1 f II II Al =- Ee X'X II 11 I'

< ///SÃ /////If 9

////I ./// /larrup ZZ.

ROCHESTER GAS AND ELECTRIC CORPORATION ~ 89 EAST AVENUE, ROCHESTER, N.Y. 14649 JOHN E. MAIER TELEPHONE Vice President AREA COOK Tle 546-2700 February 18, 1982 Director of Nuclear Reactor Regulation C'6gg)1II-@

Attention: Mr. Dennis M. Crutchfield, Chief Operating Reactors Branch No. 5 9 Bp 3 lg8p 12 U.S. Nuclear Regulatory Commission.

Washington, D.C. 20555 RADII~ PIIIt/O'IlI/gg AC "III I

Subject:

SEP Topic'II-4.A, Tornado Missiles R. E. Ginna Nuclear Power Plant, Docket No.,50-244

Dear Mr. Crutchfield:

This letter is in response to the draft Safety Evaluation Report for this topic, transmitted by letter dated September 28, 1981 from Dennis M. Crutchfield, to John E. Maier. Rochester Gas and Electric has reviewed the factual content and descriptive material in the SER, and concurs in its accuracy. At this time, RG&E is not able to agree with the design basis tornado missile v velocities specified in Section IV of the SER. As .noted in Section IV, tornadoes are significantly less frequent and less severe in the vicinity of Ginna that. in most of Tornado Region I, We consider the specified 250 mph tornado to be excessively conservative for use as the Ginna design basis tornado. In our review of SEP Topic III-2, Wind and Tornado Loadings, RG&E will quantify the design basis tornado considered suitable for the Ginna site. The spectrum of tornado missile velocities associated with that wind speed will be used in the Ginna "Tornado Missile" evaluation. It is expected that this information will be avail-able for submittal to the NRC by March 31, 1982.

Specific comments relative to equipment specified in Section V.D of the SER are provided in the attachment.

Very truly yours, John E. Maier Attachments a

'8202240224'20218 PDR ADOCK 05000244

-"P ',,PDR

I II I

l II m

Attachment:

RGSE Comments relative to 9/28/81 draft SER, Topic III-4.A, Tornado Missiles Component Cooling System Although the CCW system is generally regarded as a system required for safe shutdown, the reactor can be placed in a safe hot shutdown condition, and eventually cooled to a cold shutdown condition, without use of this sytem. Hot shutdown is maintained by use of the charging and auxiliary feedwater systems. Cold shutdown would require either the use of a steam generator cold shutdown method (described in RGEE's fire protection safe shutdown report), or the eventual repair of the CCW system to provide cooling water to the RHR heat exchangers. Cold shutdown would thus not be effected for many days. Safe hot shutdown and slow cooldown via the steam generators could be maintained as long as necessary.

RGSE thus considers that this system could be removed from the list of equipment requiring tornado missile protection.

Refueling Water Storage Tank This tank is vulnerable to damage from tornado missiles above the operating floor of the auxiliary building. Flooding of safety-related equip-ment. is the only concern. The protected portion of the tank (36 feet) is more, than sufficient to make 'up from "contraction in going to eventual cold 'shutdown (as noted', in Regulatory Guide 1.1.7).

Electrical buses 14, 17, and 18 As part of Ginna fire protection safe shutdown system, an additional safety-related bus (14A) will be installed. Placement of this additional bus, which will be separated from bus 14, should preclude the need to protect bus 14. Electrical buses 17 and 18 are vulnerable to tornado missile damage, and require further evaluation.

Service Water System The Service Water system is vulnerable to damage from tornado missiles.

Diesel generators and their fuel supply In addition to the tornado missile protection evaluations specified in the SER, it should also be noted that the built-up roof of the diesel generator rooms is not expected to withstand tornado missiles.

Relay room This room is vulnerable to damage from tornado missiles.

ag 4)

I l M K

JI l l,

7. Main steam line "B" Since the steam lines are of very thick-walled construction (approximately 1.4 inches thick),

it is not expected that there would be any penetration by tornado missiles. RGSE believes that this item could be deleted from the list of equipment requiring further tornado missile evaluation.

8. The top surface of the spent fuel pool The consequences of a tornado missile impacting the fuel assemblies in the spent fuel pool was addressed in RGSE's response to an August 5, 1976 letter from Leon D. White, Jr. to A. Schwencer, NRC. This evaluation is enclosed.

Based on that evaluation, it is considered that this item can be deleted from further tornado missile protection consideration.

9. Boric Acid Tanks As noted in the evaluation, the boric acid tanks are not required for safe shutdown. The only consideration is flooding of safety-related equipment.

Although the Boric Acid Tanks are protected by concrete walls on the sides, a tornado missile could damage the tank from the top. However, even if both tanks completely emptied, the entire contents (about 6,000 gallons) would be insuffi-cient to flood any safety-related equipment located in the basement of the auxiliary building. Thus, RGGE considers that these tanks can be deleted from consideration relative to tornado missile protection requirements. N I k

ir N

4