ML20011A702

Responds to NRC 810908 Telcon Re Violations Noted in IE Insp Repts 50-254/81-04 & 50-265/81-04.Forwards Addl Info Re Effect Upon Safe Shutdown Analyses of Fire in Vicinity of nonfire-rated Hatches

ML20011A702
Person / Time
Site:	Dresden, Quad Cities
Issue date:	09/28/1981
From:	Rausch T COMMONWEALTH EDISON CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML20011A700	List: ML20011A702 ML20011A704
References
NUDOCS 8110290308
Download: ML20011A702 (7)

Text

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., f"N - c0mm0RW980th EdlSOR

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[ ' ) one First National Plaz9, chicago, Illinois

\ v 7 Address Reply to: Post Office Box 767 -

\, / Chicago, lilinois 60690

, September 28, 1981 4

I Mr.-James G.iKep'pler, 01 rector Directorate'of Inspection.and Enforcement - Region'III U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, IL 60137

Subject:

Dresrien Station Units 2 and 3 0.uad Cities Station Units 1 and 2 Additional Information Concerning Fire Protection Analyses Associated With Inspection Report 50-254/81-04 ar.d 50-265/81/04 NRC Docket Nos. 50-237/249 and 50-254/265 Reference (a): T. J. Rausch letter to J. G. Keppler dated July 8, 1981.

(b): Telephone' conversation from J. Grobe to R. Stachniak concerning IR 265/81-04 Item 1, dated September 8, 1981.

Dear Mr. Keppler:

In Reference (a), Commonwealth Edison provided an additional response to the subject Inspection Report concerning the effect upon safe shutdown analyses of a fire in the vicinity of certain non-fire rated' hatches. Upon review of this response, Mr.

J. A. Grobe of your staff verbally' requested (Reference (b)) that we provide additional-information concerning this matter for Quad Cities Station and equivalent information for Dresden Station. A complete response for both stations to this request is attached.

Please address any questions you may have concerning this matter to this office.

Very truly yours, Y=ffwd Thomas J. Rausch Nuclear Licensing Administrator Boiling Water Reactors Attachment ,

cc: Region III Inspector - Dresden Region III Inspector --Quad Cities 2585N O fo$ p. 7,9 N O.

F ATTACHMENT'-

QUAD-CITIES l'&'2 "Can.a fire in a cable tunnel propagate 1through-non-fire rated hatch zat' turbine building . floor elevation 595', and will Lsuch: a : fire:

' damage _ essential safe shutdown ' equipment cin the > turbine building?"

h .~ Response i

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j; A postulated fire in the Unit 1 Canle. Tunnel would affect-i Division IILcables only. If such a fire were .to propagate through the' unrated manhole at column / row 17/F, -safe shutdown could' be accomplished t independent-of such a fire by . local manual operation of the electromatic

>, relief valves in the Reactor Building _and the RHR: System (Division I) in-the.LPCI and torus cooling modes. _The only saf e shutdown ~eauipment i

' located in-the manhole vicinity are Division II cablesiin risers from the 1 -tunnel to the groun'd floor. The loading on the ground' floor _is only 2

10,000' Btu /ft , equivalent to a fireuof.less than 1/2. hour severity.

All of'the significant~ fire hazards on this floor, including . the : Reactor Fcedwater Pumps and the Cable concentrations over 4kV- Buses 11 rand 12,

{ are protectcC by automatic water suppression. systems. Automatic water

[ suppressionLis also provided at.the'non-flammable EHC Fluid Reservoir,.

[ the trackways area,- and CaDie penetration areas.

t I . A postulated fire; in'the Unit 2 Cable LTunnel would affect

= cables of both safety divisions.'- If such a fire were -to propagate I

' through the unrated l manhole -at .17/G, -Unit 2 shutdown could- be n

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9 accomplished independent of such a fire by local manual operation of the electromatic relief valves in the Reactor Building and the RHR system in the LPCI and torus cooling modes. Unit 1 shutdown could be accomplished as described above. The only saf e shutdown equipment in the surrounding area are Unit 1 Division II cables as discussed above.

If a fire in the Unit 2 Cable Tunnel were to propagate through the manhole at column / row 9/G-H, safe shutdcen could bc accomplished independent of such a fire by local manual operation of the electromatic relief valves in the Reactor Building and the RHR System in the LPCI and torus cooling modes. The only safe shutdown equipment in the surrounding area are Division II cable trays which run along Row G. All of the significant fire hazards on this floor, similar to the Unit 1 side, are protected by automatic water suppression systems.

If a fire in the Unit 2 Cable Tunnel were to propagate through the hatchway located at column / row 12-13/F-G, saf e shutdow n could nevertheless be achieved by local manual operation of the electromatic relief valves in the Reactor Building and the RHR System in the LPCI and torus cooling modes. The only saf e shutdown equipment in the hatch vicinity are Unit 1 Division II cables and Unit 2 Division I and II cables. The necessary Division I RHR power feed cables are independent of this area.

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Due to the low fire loading;.3" curbs around all-manholes, automatic-suppression systems, and independent . safe -shutdown capability,

the postulated spread of fire from either cable tunnel to the turbine.

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- building ground floor is not a significant event, and will :not prevent.

safe shutdown of either unit.

Associated control cables for the alternate' shutdown capability. -

at Quad Cities are currently under review i n response to an NRC request dated February 20, 1981. This evaluation will be completed and . submitted h for review by November 15, 1981.

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ATTACHMENT DRESDEN 2 &'3 '-

Can a fire in the cable tunnel propagate through non-fire rated hatches _ at turbine building flocr elevation 517', and will such 'a-fire damage essential safe shutdown equipment in the turbine building?

A postulated fire in the cable tunnel would affect both_ safety divisions of Unit 3 cables. If such a fire _ were to propagate through -the unrated manhole at column / row 40/F, the only safe shutdown equipment located in the surrounding area Unit 2 Division II cable trays, and the Unit 2 Condensate Transfer Pumps. Unit 3 shutdown could be accomplished independent of such a fire by manaally initiating the isolation ,

condenser, and locally controlling the Control Rod Drive Pumps and ,

Condensate Transfer Pumps. Unit 2 shutdown could be accomplished in a similar manner since the Unit 3 Condensate Transfer Pumps.are norma'ly crosstied to feed both units. The fire loading on the ground floor is 2

only 27,000 Btu /ft , equivalent tc a fire of less than 1/2 hour severity. All of the significant fire hazards on this floor, i ncluding the Reactor Feedwater pumps and the cable concentrations in the' northeast corner (northwest corner f or-Unit 3), are protected by automEtic water

. - suppression systems. Automatic water suppression is also provided- at the non-flammable EHC Fluid Reservoir and the trackway area.

If a postulated fire in the cable tunnel were to propagate' s

through the unrated hatch at 45/F, the saf e shutdown eauipmen,t _which could be affected includes Unit 3 Division I and II cables and Unit 2 Division Il cables. Safe shutdown of both units can be accomplished

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. independent of such a fire by manual initiation of the-Isolation

Condend'ers and local control of the- Condensate ' Transfer Pumps 'and; Control Rod Drive Pumps. All:of the significant fire' hazards on the ground floor, as = described above f or the Unit 2 manhole analysis, are protected-by automatic- water suppression systems.

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i If a postulated fire in th'e cable tunnel were to propagate-through the unrated manhole at 48/F, the safe shutdown equipment which 3

could be affected includes cables in both unit 3 safety divisions, and' 1

[7 the Unit 3 Condensate _ Transfer Pumps. Unit 3 shutdown could bei e' accomplished independent of such a fire by manual initiation of-the

,~ Isolation Condenser, and local' control of the Control Rod Drive: Pumps.

[ The Unit -2 Condensate Transfer Pumps will be available to provide makeup.

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totheUnij-3Is'olationCondenser.

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. If a postulated fire in the cable. tunnel were to propagate t'hrough the unrated manhole at 56/E, the saf e shutdown equipment which could be affected includes cables in both Unit 3 safdty divisions. : Safe-i shutdown can be accomplished independant of such a fire by manual

? initiation of the Isolation Condenser with makeup f rom the Condensate Transfer Pumps-or Unit 2 Service Water Pumps. A: fire'in this' area could-

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af fect- the pcier, cables tl, the Control Rod Drive Pumps. HPCI cables are_.

v also -routed inI th e ' cable ' tunnel. ' 'However, there are no- HPCI _ cables in r.

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th~e tunnellwest of' column 50. Considering the water- deluge system ll ,

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' covering this area, the physical separation in excess' of 150', and t:1e

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two' independent automatic sprinkler systems in the cable tunnel, either the HPCI -system or CRD system will be. available f or reactor makeup- in case of a postulated fire near 56/E.

Associated cor. trol ' cables f or the alternate shutdown capability at Dresden are currently under review in response to an NRC request, dated February 20, 1981. This evaluation will be completed and submitted g for review by November 15, 1981.

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