ML20236G303

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Provides Addl Info Re Util 870702 Request to Revise/Clarify Penetration Seals Surveillance Requirements.Hourly Fire Watches Presently Maintained on Listed Affected Areas Until NRC Concurrence Received on Request
ML20236G303
Person / Time
Site: Fort Saint Vrain Xcel Energy icon.png
Issue date: 07/27/1987
From: Waremboug D
PUBLIC SERVICE CO. OF COLORADO
To: Calvo J
NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM), Office of Nuclear Reactor Regulation
References
P-87269, TAC-54373, NUDOCS 8708040200
Download: ML20236G303 (13)


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2420 W. 26th Avenue, Suite 1000, Denver, Colorado 80211 July 27, 1987 Fort St. Vrain Unit No. 1 P-87269 U. S. Nuclear Regulatory -Commission ATTN: Document Control Desk Washington, D.C. 20555 Attention: Mr. Jose A. Calvo .

Director, Project Directorate IV I Docket No. 50-267

SUBJECT:

Justification for Penetration Seal Surveillance Requirements  !

REFERENCE:

1) PSC letter, Warembourg to Calvo, dated 7/02/87 (P-87241) 1

Dear Mr. Calvo:

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Per our conversation with Messrs. K. Heitner and 0. Kubicki on July l 22, 1987, we have attached additional information concerning PSC's request to revise / clarify the Fort St. Vrain (FSV). penetration seals' surveillance requirements noted in Reference No. 1. The additional information provided for each group of seals includes:

- the location of the seals

- the criteria to be' applied for surveillance

- the Fire Protection Shutdown /Cooldown equipment. located adjacent to the seals

- the original basis for the seal installation

- the PSC written commitments on the seals

- the applicable NRC approval of the seals j l

With the exception of case 3, the penetration seals in question are not relied upon to serve a safety function and need not be classified and surveillance as " fire barrier penetration seals", as explained below:

1. The . seals in the floors of the Reactor and Turbine buildings were not required to comply with the NRC's BTP 9.5-1, Appendix A because of the nature of the'FSV open space. design concept of those buildings. A three hour fire rated seal would be of no use i

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P-87269 Page 2: 1 July 27, 1987 i next to an open grating or discontinuous. floor. The Fire  :

Protection Shutdown /Cooldown Trains and the Alternate. Cooling  ;

Method equipment, identified in the FSV Ap~pendix-R. Evaluation, is '

separated by distance and does not rely upon these seals to be . -

intact during or after a fire to perform a safety related fire l barrier function.

2. The Access Control. Bay seals are not needed as " fire barrier.  !

penetration seals" because _the FSV Appendix R Evaluation considers the entire Turbine Bui.1 ding as a single fire area, except for five specific rooms. These seals could not be relied .

upon in complying with the NRC's BTP 9.5-1, Appendix'A criteria because of the nature of the FSV open space design concept in:the Turbine Building, including the AccessLControl Bay.. A rated fire  !

seal in this area would be of no use next to a large. opening. ore _;

open grating floor. The Fire Protection Shutdown /Cooldown Trains i and the Alternate Cooling Method equipment, . i_dentified in the Appendix R Evaluation, is separated by distance and does' not rely upon these seals to be intact during or after a fire to perform a safety related fire barrier function.

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3. The Auxiliary Electrical Equipment Room floor seals will be. i maintained as " gas tight" unrated fire seals. and surveillance' H annually, just as PSC had previously committed to the NRC to do. l

! There is no change in the requirements or classification of these i

! seals. In 1978, the NRC and PSC. agreed that these seals are

" equivalent to a 3-hour fire rating." These seals will remain!as 1

" fire barrier penetration seals" and be surveillance under FSV-  ;

Technical Specifications LCO 4.10.4 and SR 5.10.4..- ,

4. The Analytical Instrument Room seals will:not be considered'"to be installed between vital plant areas" and will not' be surveillance, since the Reactor Building has been considered as a single fire area in the FSV Appendix-R Evaluation. 'PSC elected to define this room as a separate fire area.in the 1978 Fire Hazards Analysis, but did not need to do so to' comply with the.

NRC's BTP 9.5-1, Appendix A. The Fire Protection Shutdown /Cooldown Trains and the Alternate Cooling Method equipment identified in the Appendix R Evaluation, is separated-by distance and does not rely upon~ these seals to be' intact during or after a fire to perform a safety related fire barrier function.

None of the seals in Cases.1, 2 and 4 are considered to be " fire barrier penetration seals installed between. vital plant areas", nor are they needed "to prevent the spread of a fire from one vital area-

P-87269 Page 3 July 27, 1987 to another", per FSV Technical Specifications LC0 4.10.4 anu SR 5.10.4 and need not irivoke the requirements of the LC0 or be surveillance.

On July 25, 1987, the NRC Resident Inspector, Mr. R. E. Farrell and the PSC Fire Protection Engineer, Mr. G. D. Schmalz, walked down i typical penetrations in the general areas in question, and found that i fire penetration seals in the interior floor and walls would not I affect the safety of Fort St. Vrain during or after a fire.

Therefore, PSC requests NRC approval of the particular penetration.  !

seal surveillance requirements as noted above, to clarify the proper {

limits of the FSV Technical Specifications. PSC is presently  ;

maintaining hourly fire watches on the above affected areas until NRC d concurrence is received on this request.

If you have any questions concerning this matter, please contact Mr. M. H. Holmes at (303) 480-6960.

1 Very truly yours,

.0 /Y Wm / i D. W. Warembourg Manager Nuclear Engineering Division a

DWW/ RAS:bac CC: Regional Administrator, Region IV ATTN: Mr. J. E. Gagliardo, Chief Reactor Projects Branch Mr. Kenneth Heitner Project Manager, NRR Mr. Dennis Kubicki Fire Protection Engineer Plant System Branch, NRR Mr. R. E. Farrell Senior Resident Inspector Fort St. Vrain

Attachment P-87269 s

Page 1 of 10 la. Location:

Reactor Building floors Seal Criteria:

Seals will not be considered to be vital fire area seals and uill notbesurveillapced.

Equipment Adjacent to Seals:

Train A Fire Protection Shutdown /Cooldown model equipment within the reactor building are spatially separated by minimum 50 ft.

horizontally and 30 ft. vertically, from Train B equipment, except for noted exemptions in the Appendix R Evaluation, Vol. A.

This separation meets the intent of 10 CFR Appendix R Part III. G with no credit for any floor seal in the Reactor Building.

Original Basis for Seals:

Per Sargent and Lundy Standard EA-176, fire stops were installed at selected locations as designated on construction drawings.

Various ones of these locations are now obsolete based upon the Reactor Building open space design and the current definition of fire areas per the FSV Appendix R Evaluation, Vol 3.

1978 Response to BTP 9.5-1, Appendix A:

, The 1978 FSV Response to BTP 9.5-1, Appendix A on page 3-35 I stated:

" Penetrations within the Reactor Building and Turbine Building between fire areas (floor levels) are not sealed by nature of the open space design concept."

1978 Fire Hazards Analysis:

The 1978 Fire Hazards Analysis transmitted to the NRC via Reference 1 states on page 4-7:

"The building is divided into fire areas by floor level.... The open structure design concept employed in the building consists of open steal floor grating, open stairways, and machinery and personnel access openings in walls and floors.... System piping, electrical cable in trays, risers, conduit, and ventilation ducts penetrate the floors (fire areas) and missile barrier l

Attachment P-87269 Page 2 of 10 I

wall (fire zones) without fire stops or ventilation dampers.... Penetrations without fire rated fire stops or fire dampers are considered acceptable, based on consideration of the fire load calculated for each fire area."

NRC Approval:

The seals to be deleted were never reviewed and formally approved l by the NRC.

i 10 CFR 50, Appendix R Analysis:

The FSV Appendix R Evaluation, Volume 3, pages 2-2 and 2-5, considers the reactor building to be one fire a rea , instead of dividing it by floors.

References:

1. PSC letter, Fuller to Gammill, dated October 13, 1978 (P-78167)
2. PSC letter, Fuller to Gammill, dated November 13, 1978 (P-78182)
3. FSV Appendix R Evaluation, Volumes 3 and 4.
4. PSC letter, Warembourg to Calvo, dated July 2, 1987 (P-87241)

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Attachment P-87269 Page 3 of 10 lb. Location:

l- Turbine Building floors Seal Criteria:

Seals will not be considered to be vital fire area seals and will not be surveillance.

Equipment Adjacent to Seals:

1 Train 'A' Fire Protection Shutdown /Cooldown model equipment.within the reactor building are ' spatially separated by minimum 50 ft. 1 horizontally and 30 ft, vertically, from Train B equipment,: I except for noted exemptions in the Appendix R Evaluation, Vol.'4 This separation meets the intent of 10 CFR Appendix R.Part-III. G with no credit for any floor seal in the ' Turbine Building.

Oriainal Basis for Seals:

Per Sargent and Lundy Standard EA-176, fire stops were installed at selected locations as designated on construction' drawings.

Various ones of these locations are now obsolete based upon the Turbine Building open space design and the current definitier of fire areas per the FSV Appendix R Evaluation, Vol 3.

1978 Response to BTP 9.5-1, Appendix A:

The 1978 FSV Response to BTP 9.5-1, Appendix A on page 3-35 stated:

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" Penetrations within the Reactor Building and Turbine Building between fire areas (floor levels) are not sealed by nature of the open space design concept."

1978 Fire Hazards Analysis:

The 1978 Fire Hazards Analysis, transmitted to the NRC via ,

Reference 1,. states on page 4-32: j "The building is essentially a three-level structure, except for the access. control bay.... Its physical 3 configuration, also similar to the Reactor Building, is.

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1 an open structure design consisting of open steel floor grating, open stairways, and, except as noted in the {

fire hazards analysis, contains unsegregated machinery areas. The Turbine Building has been divided into fire i

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Attachment P-87269 Page 4 of 10 areas by levels and by segregated rooms.... As was done I in the Reactor Building, when considering the effects of the design basis fire, consideration was given to safety related equipment and additional combustibles that could be involved based on proximity to the fire i

area concerned."

NRC Approval:

The seals to be deleted were never reviewed and formally approved <

by the NRC. j 10 CFR 50, Appendix R Analysis:

The FSV Appendix R Evaluation, Volume 3, page 2-6 states: ,

l "Except for the five listed areas in Sections 2.2.12 l

thru 2.2.16, the turbine building is considered one fire area and includes the access control bay."

Sections 2.2.12 through 2.2.16 or, pages 2-6 and 2-7 identify the five areas as being:

Diesel Generator Rooms, Auxiliar Reservoir Room, Turbine Lube Oil Clean(y Boiler Room,

/ Dirty) Turbine Storage Lube aOil Room, Hydrogen Storage Room.

References:

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1. PSC letter, Fuller to Gammill, dated October 13, 1978 (P-78167)
2. PSC letter, Fuller to Gammill, dated November 13, 1978 (P-78182)
3. FSV Appendix R Evaluation, Volumes 3 and 4.
4. PSC letter, Warembourg to Calvo, dated July 2, 1987 (P-87241) i 1

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Attachment P-87269 Page 5 of 10

2. Location:

Access Control Bay Floors , Walls and Ceilings on all levels, (only "J" wall seals will be maintained and surveillar,ced) 1 Seal Criteria:

Seals will not be considered to be vital fire area seals and will not be surveillance.

Fire Protection Shutdown /Cooldown Equipment Adjacent to seals:

l "J" Wall Congested Cable Area, Reactor Building Exhaust Filters )

and Fans. 1 i

Original Basis for Seals:

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The 1978 Fire Hazards Analysis, (Reference 1) 1978 Fire Hazards Analysis j

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The 1978 Fire Hazards Analysis, transmitted to the NRC via f Reference 1 discusses this fire area on pages 4-33 through 4-36, and states: I q

"....All fire area boundary doors are non-rated steel doors.... The reinforced concrete floor and fabricated steel walls and doors are considered to be of a fire rating greater than the calculated fire load for this i

area. Ducting penetrating these barriers is not fitted with fire dampers, and several unsealed openings are i provided for piping penetrations." '

_NRC Approval:

The seals to be deleted were never reviewed and formally approved by the NRC.

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Attachment ,

P-87269 Page 6 of 10 10 CFR 50, Appendix R Analysis:

The FSV Appendix R Evaluation, Volume 3, page 2-6 states:

"Except for the five listed areas in Sections 2.2.12 thru 2.2.16, the turbine building is considered one fire area and includes the access control bay."

Sections 2.2.12 through 2.2.16 on pages 2-6 and 2-7 identify the j five areas as being- l l

Diesel Generator Rooms, Auxiliar /

Reservoir Room, Turbine Lube Oil Clean(y Boiler Room,

/ Dirty) Turbine Storage Lube Room and Oil Hydrogen Storage Room.

References:

1. PSC letter, Fuller to Gammill, dated November 13, 1978 (P-78182)
2. Appendix R Evaluation, Volume 3
3. PSC letter, Warembourg to Calvo, dated July 2,1987 (P-87241) l l

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. Attachment P-87269 4 Page 7 of 10

3. Location: i Auxiliary Electrical Equipment Room Floor l

Seal Criteria.

Seals will be maintained as " gas tight" unrated fire seals and I surveillance annually.

Fire Protection Shutdown /Cooldown Equipment Adjacent to Seals:

480 Volt Switchgear Room equipment including: 480 V switchgear ,

Trains A & B (non ACM) and station battery chargers; Train A and  !

B Auxiliary Electrical instrument / control cabinets.

Original Basis for Seals:

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See references for historical information, as listed below. The '

final basis of these seals may be found in Reference 5, which states:

"PSC maintains that this modification offers a significant improvement to these floor seals that, based on comparison with other floor seal designs that  !

have been fire tested, makes the modified floor seal equivalent to a 3-hour fire rating."

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BTP 9.5-1, Appendix A Analysis- 1 The FSV 1978 Response to BTP 9.5-1, Appendix A transmitted to the NRC via P-78167, states on page 3-65:

"The Fire protection provisions in these areas have ,

been reviewed, upgraded, and approved by the NRC." i NRC Approval: i NRC letter, Denise to Fuller, dated March 31,1978(G-78029), l states:

"We find that the proposed floor penetration seal l design using Dow Corning silicone foam material is an acceptable three hour fire barrier to be used in the Fort St. Vrain three-room complex."

Attachment P-87269 Page 8 of 10 10 CFR 50, Appendix R Analysis:

The FSV Appendix R Evaluation, Volume 3, page 2-5, states:

"Within the three room control building, the three rooms are, in fact, considered by the NRC to be i separate fire areas; however, it is not necessary to evaluate them as being so for the purposes of Appendix R."

The Auxiliary Electric Equipment Room is considered a part of the i congerted cable areas. For major fires in congested cable areas, the Alternate Cooling Method would be used per FSV Appendix R Evaluation, Volume 1, Appendix A (PSC letter to NRC dated August 17, 1984 (P-84281)). '

References:

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1. PSC letter, Walker to Clark, dated June 18, 1976 (P-76135) i
2. PSC letter, Walker to Clark, dated August 2,1976 (P-76172)
3. PSC letter, Fuller to Denise, dated September 19,1977(P-77194) )
4. NRC letter, Denise to Fuller, dated March 31, 1978 (G-78029)
5. PSC letter, Fuller to Gammill, dated October 13, 1978 (P-78167)
6. PSC letter, Lee to Johnson, dated August 17, 1984 (P-84281)
7. PSC letter, Warembourg to Calvo, dated July 2,1987 (P-87241) ]

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' Attachment P-87269 l Page 9 of 10 J

4. Location:

J Analytical Instrument Room (Reactor Building Level 7, el. 4829')

Seal Criteria:

Seals will not be considered vital area fire seals and will not I be surveillance. ]

1 Fire Protection Shutdown /Cooldown Equipment Adjacent to Seals:

"J" Wall Congested Cable Area (has detection and suppression). J Reactor Plant Cooling Water Pumps (has detection) {

l Original Basis for Seals:

The 1978 Fire Hazards Analysis, (Reference 1) ]

1 1978 Fire Hazards Analysis The 1978 Fire Hazards Analysis, submittad to the NRC via Reference 1, does not define the Analytical Instrument Room as a separate fire area, but includes it as part of the "PCRV and auxiliary Equipment Area" on page 4-17 through 4-18, which states:

....The Instrumeat Room, enclosed by concrete walls, floor and ceiling, contains no safety related equipment.... Penetrations into the Instrument Room for piping, cable and ventilation ducting are sealed for air tightness. The room is maintained at a small negative pressure relative to Reactor Building pressure."

NRC Approval:

The seals to be deleted were never reviewed and formally approved by the NRC.

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Attachment P-87269 Page 10 of 10 10 CFR 50, Appendix R Analysis:

The FSV Appendix R Evaluation, Volume 3, pages 2-2 and 2-5, considers the Reactor Building to be one fire a rea , instead of dividing it by floors, PCRV, etc.

References:

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1. PSC letter, Fuller to Gammill, dated November 13,1978(P-78182) j
2. FSV Appendix R Evaluation, Volume 3 l
3. PSC Telecopy to Heitner, dated July 8, 1987 l
4. PSC letter, Warembourg to Calvo, dated July 2, 1987 (P-87241) l l

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