ML20138H699
| ML20138H699 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 08/08/1985 |
| From: | Oprea G HOUSTON LIGHTING & POWER CO. |
| To: | Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| References | |
| OL-A-074, OL-A-74, NUDOCS 8510290125 | |
| Download: ML20138H699 (33) | |
Text
,
$5 f
The Light r-company n_,..., us,,,,,-..
.. m u..m,e n..
.1~ ="i = =-u O l
- "s 53 June 9,,1931 ST-HL-AE-676 SFN
- V-0530-Mr. Karl Seyfrit Director, Region IV Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 1000 Arlington, Texas 76012
Dear Mr. Seyfrit:
South Texas Project Units 1 & 2 Docket Nos. STN 50-498, STN 50-499 First Interim Report Concerning Heating, Ventilation and Air Conditioning Design On May 8, 1981, pursuant to 10 C.F.R. 50.55(e), Houston Lighting and Power Company notified your office of a potentially reportable item concerning the consideration of certain faulted condition heat loads in the design of portions of the Heating, Ventilating and Air Cor.ditioning (HVAC) system.
Based on our assessment of prelimir.ary thermal environmental data, certain spaces and cubicles 5,ithin the Mechanical-Electrical Auxiliary Building and the Fu'.:1 Handling Building might require additional HVAC capacity.
A conceptual design for supplemental HVAC based on equip-
- r. 7t design qualification temperatures and equipment heat losses for all modes of plant operation should be available by July 1, 1981.
The design modifications will supplement the existing HVAC design.
Final HVAC design will be consistent with equipment operability requirements under the most limiting plant operating conditions.
Specific design modifications are dependent upon the results of our current evaluations.
!.iE AR REGULATORY COMAll3110N
'edetNo.
O
~
ffitla! Erh. No.
In in, matter.' - -
8510290125 Oh808 sia"
/
PDR ADOCK O 00498 mEirTinto PDR A prikant RECEIVED Inteneno,-
_ REJECTED-Cent's Off'r Irr Centracts' DATE W4
j June 9, 1981 ST-HL-AE-676 SFN: V-0530 Page 2 The next interim report concerning this item will be submitted to your office by July 30, 1981.
Should you have further questions concerning this item, please contact Mr.
M. E.
Powell at 676-8592.
Very truly yours, m
4
'h j Y
- [
G. W. Oprea Executive Vice President MEP/LRJ r
I 1
}
'l 1
i s
1 4t I
i
4
~
e Houston LighNng & Power Compam June 9,1981 cc:
J.
. Goldberg ST-HL-AE-676 D. G. Barker SFN: V-0530 C. G. Robertson i
Page 3 Howard Pyle R. L. Waldrop l
H. R. Dean O. R. Beeth J. D. Parsons J. W. Williaus J. W. driskin R. A. Frazar STP RMS H. S. Phillips (NRC)
J. O. Read (Read-Poland,Inc.)
M. D. Schwarz (Baker & Botts)
R. Gordon Gooch (Baker & Botts)
J. R. Newnan (Lowenstein, Newman, Reis, & Axelrad)
Director, Office of Inspection & Enforcement j
Nuclear Regulatory Connission Wasnington, D. C. 20555 M. L. Borcnelt Charles Bechhoefer, Esquire President Chairman, Atomic Safety 5 Licensing Board Central Power & Light Company U. S. Nuclear Reoulatory Connission P. O. Box 2121 Washington, D. C.
20555 j
Corpus Christi, Texas 78403
)
R. L. Range Dr. James C. Lamb, III Central Power & Light 313 Woodhaven Road P. U. Box 2121 Chapel Hill, North Carolina 27514 Corpus Christi, Texas 78403 R. L. Hancock Mr. Ernest E. Hill Directer of Electrical Utilities Lawrence Livermore Laboratory City of Austin University of California P. O. Box 1088 P. O. Box 808 L-123 l
Austin, Texas 78767 Livermore, California 194550 T. H. Muehlenbeck William S. Jordan, 111 i
City of Austin Harmon & Weiss P. O. Box 1088 1725 ! Street, N. W.
Austin, Texas 78767 Suite 506 Washington, D. C.
20006 J. B. Poston Lanny Sinkin Assistant General Manager of Operations Citizens Concerned About Nuclear Power j
City Public Service Board 5106 Casa Oro P. O. Box 1771 San Antonio, Texas 78233 San Antonio, Texas 78296 4
i A. vonRosenberg Citizens for Equitable utilities, Inc.
City Public Service Board c/o Ms. Peggy Buchorn P. O. Box 1771 Route 1, Box 1684 l
San Antonio, Texas 7J296 Brazoria, Texar 77422 i
Brian E. Berwick, Esquire Jay Gutierrez, Esquire Assistant Attorney for the State of Texas Hearina A**orney
{
P. O. Box 12548 Office of che Executive Legal Director Capitol Station
2055s 6 o 41
'l[
The Light COmpMy sousion tighting & comer eo. nes iroo noouoo. Tem 77ooi <ri3> zu.raii July 29, 1981 ST-HL-AE-708 SFN: V-0530 Mr. Karl Seyfrit Director, Region IV Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite ;000 Arlington, Texas 76012
Dear Mr. Seyfrit:
South Texas Project Units 1 & 2 Docket Nas. STN 50-498, STN 50-499 Second Inte-im Reoort Concerning Hea:ia), Ventilation and Ai. Conditioninq Desian On May 8, 1981, pursuant to 10CFR50.55(e), Houston Lighting & Power Company notified your office of an item ccncerning the consideration of certain faulted condition heat loads in the design of Dortions of the Heating, Ventilation and Air Conditioning (HVAC) system. Based on an assessment of preliminary thernal environmental data, certain spaces and cubicles within the Mechanical-Electrical Auxiliary Building (MEAB) and the Fuel Handling Building (FHB) will likely require additional HVAC capacity.
A conceptual design that has been supplied by Brown & Root is being evaluated to ensure that equipment design qualification temperatures and equipment heat losses for all mcdes of plant operation are included in tne design. Specific design modifications are deoendent uoon the results of our current evaluations.
The next interim report corcerning this item will be submitted to your office by October 23, 1981.
If there are any questions concerning tnis item, clease contact Mr. Michael E. Powell at (713) 676-8592.
Very trup yours, M.
rg a.
f,
Exec ive V e President MEP/amj
n -
Houston Lighting & Power Company cc:
J. H. Goldberg July 29, 1981 J. G. Dewease ST-HL-AE-708
- 0. G. Barker SFN: V0530 C. G. Robertson Page 2 Howard Pyle R. L. Waldrop H. R. Dean D. R. Beetn J. D. Parsons J. W. Williams J. W. Briskin J. E. Geiaer STP RMS H. S. Pnillips (NRC)
J. O. Read (P.ead-Poland,Inc.)
M. D. Schwarz (Baker & Botts)
R. Gordon Gooch (Baker & Botts)
J. R. Newman (Lowenstein, Newman, Reis, & Axelrad)
Director, Office of Inspection & Enforcement Nuclear Regulatory Connission Washington, D. C. 20555 R. L. Range /G. W. Muench Charles Bechhoefer, Esquire Central Power & Light Comoany Chairman, Atomic Safety & Licenting Board U. Box 2121 U. S. Nuclear Regulatory Comnission Larous Christi, Texas 78403 Wasnington, D. C.
20555 R. L. Han:ock/G. Pokorny Dr. James C. Lamb, !!!
City of Austin 313 Woodhaven Road P. O. Box 1088 Chapel Hill, North Carolina 27514 Austin, Texas 78767 J. B. Poston/A. vonRosenberg Mr. Ernest E. Hill City Public Service Board sawrence Livernore Laboratory P. U. Box 1771 University of California San Antonio, Texas 78296 P. O. Box 808, L-46 Livermore, Calitnrnia 94550 Brian E. Berwick, Esquire William S. Jordan, !!!
Assistant Attorney for the State of Texas Harnon & Weiss P. O. Box 12548 1725 1 Street, N. W.
Capitol Station Suite 506 Austin, Texas 78711 Washington, D. C.
20006 Lanny Sinkin Citizens for Eouitable Utilities, dnc.
Citizens Concerned About Nuclear Power c/o Ms. Peggy Buchorn 5106 Casa Oro Route 1, Box 1684 San Antonio, Texas 78233 Brazoria, Texas 77422 Jay Gutierrez, Esquire Hearing Attorney Of fice of tne Executive Legal Director U. S. Nuclear Regulatory Cornission Washington, D. C.
20555 Revision Date 7-28-81 I
t
4 2he Light COEhdNf Houm n Lighting & Power PO. Bos 1700 llouston Texas 77001 G13:228@211 October 23, 1981 ST-HL-AE-743 SFN: V-0530 Mr. Karl Seyfrit Director, Rer; ion IV Nuclear Regulatory Co _ission 611 Ryan Plaza Drive, Suite 1000 Arlington, Texas 76012
Dear Mr. Seyfrit:
South Texas Project hits 1 & 2 Docket Nos. STN 50-498, STN 50-499 Third Interim Report Concerning Heating, Ventilation and Air Conditioning Desien Due to the recent events relating to the change in Architect-Engineers on the South Texas Project, all work relating to this item of concern has been tenporarily halted.
It is anticipated that all progress ~ accomplished to date vill be reviewed by Bechtel during the transition period. Upon conpletion of this review a schedule vill be trans=itted to your office advising of the sequence of activities alt g with their anticipated conpletion dates.
The next interim report concerning this item will be sub=itted to your office by May 27, 1982.
If there are any questions cencerning this item, please contact Mr.
Pdchael E. Powell at (713) 676-8592.
Very truly yours, n
JO r
~,
G.
n' '
- rea, r.
Exedtive'VicePresident RRH/ble I
l
Hour.on Lighting & Power Nnpam cc:
J. H. Goldber9 October 23, 1981 J. G. Dewease ST-HL-AE-743 D. G. Barker SFN:
V-0530 C. G. Robertson Page 2 Howard Pyle R. L. Waldrcp H. R. Dean R. A.-Frazar D. R. Beeth J. D. Parsons J. W. Willians J. W. Briskin J. E. Geiger STP RMS H. S. Phillips (NRC)
J. O. Read (Read-Poland, Inc.)
M. D. Schwarz (Baker & Botts)
R. Gordon Gooch (Baker & Botts)
J. R. Newman (Lowenstein, Newman, Reis, 8 Axelrad)
Director, Office of Inspection & Enforcement Nuclear Regulatory Co nission Washington, D. C. 20555 R. L. Range /G. W. Muench Charles Bechhoefer, $ squire Central Power & Light Conpany Chairman, Atomic Safety & Licensing Board P. O. Box 2121 U. S. Nuclear Regulatory Cornission Corous Christi, Texas 78403 Washington, D. C.
20555 R. L. Hancock/G. Pokorny Dr. James C. Lamb, III City of Austin 313 Woodhaven Road P. O. Box 1038 Chapel Hill, North Carolina 27514 Austin, Texas 78767 J. B. Poston/A. vonRosenberg Mr. Ernest E. Hill City Public Service Board Lawrence Livermore Laboratory P. O. Box 1771 University of California San Antonio, Texas 78295 P. O. Box 808, L-46 Livermore, California 94550 Brian E. Berwick, Esquire William S. Jordan, III Assistant Attorney General for the State Harmon & Weiss of Texas 1725 I Street, N. W.
P. O. Box 12548 Suite 506 Capitol Station Washington, D. C. '20006 Austin, Texas 78711 Lanny Sinkin Citizens for Equitable Utilities, Inc.
Citizens Concerned About Nuclear Power c/o Ms. Peggy Buchorn 5106 Casa Oro Route 1, Box 1684 San Antonio, Texas 78233 Brazoria, Texas 77422 Jay Gutierrez, Esquire Hearing Attorney Office of the Executive Legal Director U. S. Nuclear Regulatory Comission Washington, D. C.
20555 Revision Date 10-20-81 i
I t
The Light COmpMy Houston U hting & Power P.O. Box 1700 Houston. Texas 77001 (713)228 9211
's 8
April 8,1982 ST-HL-AE-813 SFN: V-0530 Mr. John T. Collins Regional Administrator, Region IV Nuclear Regulatory Comission 611 Ryan P1aza Dr.. Suite 1000 Arlington, TX 76012
Dear Mr. Collins:
South Texas Project Units 1 & 2 Docket Nos STN 50-498, STN 50-499 Final Report Concerning the Fuel Handling Building HVAC Control Air System I'
On March 15, 1982, pursuant to 10CFR50.55(e), Houston Lighting & Power Company (HL&P) notified your office of an item regarding the Fuel Handling Building (FHB) HVAC Control Air System. This item was identified as being potentially reportable pursuant to 10CFR50.55(e) in the Bechtel Power Cor-poration (BPC) Task Force assessment of the findings in the Quadrex Report.
An evaluation has been perfomed which shows that this item does not meet the criteria of 10CFR50.55(e) and, therefore, is not reportable. Thus, this item is considered closed.
l If you should have any questions concerning this item, please contact Mr.
Michael E. Powell at (713) 877-3281.
Very truly y,oers.
-l J/
ea 9
Exec.tve V gi President l
MEP/blt i
f
Houston Ughting & Power, Company cc:
G. W. Op re a, J r.
April 8.1982 J. H. Goldberg ST-HL-AE-813
)
J. G. Dewease SFN: V-0530 J. D. Parsons Page 2 D. G. Barker C. G. Robertson R. A. Frazar s
J. W. Williams J. W. Briskin J. E. Geiger R. L. Ulrey i
S. M. Dew J. T. Collins NRC)
D. E. Sells NRC)
W. M. Hill, Jr.
NRC)
M. D. Schwarz Baker & Botts)
R. Gordon Gooch Baker & Botts)
J. R. Newman Lowenstein, Newman, Reis, & Axelrad)
STP RMS Director. Office of Inspection & Enforcement i
Nuclear Regulatory Commission Washington, D. C. 20555 i
R. L. Range /G. W. Muen:h Charles Bechhoefer, Esquire Centraf Power & Light Company Chaiman, Atomic Safety & Licensing Board P.~ 0. Box 2121 U. S. Nuclear Regulatory Comission Corpus Christi, Texas 78403 Washington, D. C.
20555 H. L. Peterson/G. Pokorny Dr..hmes C. Lamb, III City of Austin 313 Woodhaven Road P. O. Box 1088 Chapel Hill, North Carolina 27514 Austin, Texas 78767 t
I ~
J. B. Poston/A. vonRosenberg Mr. Ernest E. Hill City Public Service Board Lawrtnce Livemore Laboratory P. O. Box 1771 University of California San Antonio, Texas 78296 P. O. Box 808, L-46 Livemore, Califomia 94550 3
'. Brian E. Berwick, Esquire William S. Jordan, III Assistant Attorney General Harmon & Weiss for the State of Texas 1725 I Street, N. W.
P. O. Box 12548 Suite 506 Capitol Station Washington, D. C.
)
Lanny Sinkin Citizens for Equitable Utilities, Inc.
Citizens Concerned About Nuclear Power c/o Ms. Peggy Buchorn i
i 5106 Casa Oro Route 1. Box 1684 l
San Antonio, Texas 78233 Brazoria, Texas 77422 Jay Gutierrez, Esquire
'\\
Hearing Attorney Office of the Executive Legal Director i
U. S. Nuclear Regulatory Comission
, Washington, D. C.
20555 Revision Date 03-30-82 w
%e
g The Light COmpally Houston 1.j hting1: Power P.O. Box 1700 Houston, Tens 77001 (713)228-9211 g
May 26, 1982 ST-HL-AE-835 SFN: V-0100 Mr. John T. Collins Regional Administrator, Region IV Nuclear Regulatory Comission 611 Ryan P1aza Dr.. Suite 1000 Arlington, Texas 76012
Dear Mr. Collins:
South Texas Project Units 1 & 2 Docket Nos. STN 50-498, STN 50-499 Fourth Interim Report Concerning Heating, Ventilation and Air Conditioning Design On May 8,1981, pursuant to 10CFR50.55(e), Houston Lighting & Power Company (HL&P) notified your office of an item concerning the consideration of certain faulted condition heat loads in the design of portions of the Heating.
Ventilation and Air Conditioning (HVAC) system.. Based on an assessment of preliminary thermal environmental data, it was identified that certain spaces and cubicles within the Mechanical-Electrical Auxiliary Building (MEAB) and the Fuel Handling Building (FHB) will likely require additional HVAC capacity.
A conceptual design based on the afommentioned preliminary data was previously developed by Brown & Root, Inc. (B&R) and fomarded to HL&P for consideration.
In addition, in order to expedite resolution of this item, two consultants were engaged by B&R to perform system review, evaluation and design recommendation activities. The reports by the consultants have been received by B&R and transmitted to Bechtel Power Corporation (BPC) as part of the transition activities. BPC is presently in the process of performing a detailed review of the South Texas Project (STP) HVAC design (including these areas of concern) as part of transition work packages EM 550, 551, 552, 553 and 555. The consultants reports will be incorporated in BPC's review.
In our third interim mport, HL&P identified that upon completion of the review by BPC, a schedule would be transmitted to your office. Currently, BPC anticipates completion of the HVAC work package activity by mid-September 19N.
In our next interim report HL&P will provide a program description and
~
Hounon Ughdng & Power Compan)
Fourth Interim Report Concerning ST-HL-AE-835 Heating. Ventilation and Air Conditioning SFN: V-0100 Page 2 schedule of necessary activities which will include revising as necessa.ry, the appmpriate design criteria documents and verifying the HVAC equipment perfomance parameters.
The next interim report concerning this item will be submitted to your office by October 18, 1982.
If you should have any questions conceming this item, please contact Mr. M. E. Powell at (713) 877-3281.
Very t ours.
1 pr r.
Ex tive' ce President MEP/kr W
C ee l
f n
g The Light CQEhMf Houston Lighting & Power P.O. Box 1700 Houston. Texas 77001 (713) 228-9211 August 6, 1982 ST-HL-AE-866 File Number: G12.95 SFN: V-0530 Mr. John T. Collins Regional Administrator, Region IV Nuclear Regulatory Commission 611 Ryan Plaza Dr., Suite 1000 Arlington, Texas 76012
Dear Mr. Collins:
South Texas Project Units 1 & 2 Docket Nos. STN 50-498, STN 50-499 Fifth Interim Report Concerning the Heating, Ventilation and Air Conditioning Design - The Use of Fail Open Isolation Dampers On July 6,1982, pursuant to 10CFR50.55(e), Houston Lighting & Power Company (HL&P) notified your office of an item concerning the use of fail open isolation dampers in the heating, ventilation and air conditioning (HVAC) design. There is a concern that the use of fail open isolation dampers had not been adequately assessed by Brown & Root, Inc. (B&R) in the HVAC design.
In our initial notification, Mr. M. E. Powell of HL&P requested that this item be included under the envelope of the existing deficiency conceming the HVAC design. Mr. W. A. Crossman of your staff indicated that this was acceptable; however, he requested that HL&P submit a letter identifying the scope of the concern and confiming that the item will be included within the envelope of the existing HVAC item. The attached report addresses those concerns regarding the use of fail open isolation dampers that have been identified to date. Any future similar concerns will be addressed in future reports regarding the overall HVAC design..The next report regarding the overall HVAC l
design concern is scheduled to be submitted to your office by October 18, 1982.
If you should have any questions concerning this matter, please contact Mr. Michael E. Powell at (713) 877-3281.
Ve t ly,yours, t
l pIILA l
Executive Vice President MEP/kr Attachment I
Houston Ughting & Power Company cc:
G. W. Oprea, Jr.
August 6,1982 J. H. Goldberg ST-HL-AE-866 J. G. Dewease File Number: GI2.95 J. D. Parsons SFN: V-0530 D. G. Barker Page 2 C. G. Robertson R. A. Frazar J. W. Williams J. W. Briskin J. E. Geiger R. L. Ul rey S. M. Dew J. T. Collins NRC)
D. E. Sells NRC)
W. M. Hill, Jr.
NRC)
M. D. Schwarz Baker &Botts)
R. Gordon Gooch Baker & Botts)
J. R. Newman Lowenstein, Newman, Reis, & Axelrad)
STP RMS Director, Office of Inspection & Enforcement Nuclear Regulatory Commission Washington, D. C. 20555 G. W. Muench/R. L. Range Charles Bechhoefer, Esquire Central Power & Light Company Chairman, Atomic Safety & Licensing Board 1
P. O. Box 2121 U. S. Nuclear Regulatory Commission Corpus Christi, Texas 78403 Washington, D. C.
20555 H. L. Peterson/G. Pokorny Dr. James C. Lamb, III
- City of Austin 313 Woodhaven Road P. O. Box 1088 Chapel Hill, North Carolina 27514 Austin, Texas 78767 J. B. Poston/A. vonRosenberg Mr. Ernest E. Hill City Public Service Board Lawrence Livermore Laboratory P. O. Box 1771 University of California San Antonio, Texas 78296 P. O. Box 808, L-46 Livermore, Califomia 94550 Brian E. Berwick, Esquire William S. Jordan, III Assistant Attorney General Harwen & Weiss for the State of Texas 1725 I Street, N. W.
P. O. Box 12548 Suite 506 l
Capitol Station Washington, D. C.
20006 Austin, Texas 78711 Lanny Sinkin Citizens for Equitable Utilities Inc.
Citizens Concerned About Nuclear Power c/o Ms. Peggy Buchorn 5106 Casa Oro Route 1. Box 1684 San Antonio, Texas 78233 Brazoria, Texas 77422 l
Jay Gutierrez, Esquire Hearing Attorney Office of the Executive Legal Director U. S. Nuclear Regulatory Commission Washington, D. C.
20555 Revision Date 04-19-82
Fifth Interim Report Concerning the Heating, Ventilation and Air Conditioning Design - The Use of Fail Open Isolation Dampe s, I.
Sumary
'On July 6,1982, pursuant to 10CFR50.55(e), Houston Lighting & Pcnt Cogany (HL&P) notified the Nuclear Regulatory Comission (NRC) of two (2) items regarding the use of fail open dampers at the discharge of redundant supply fans in the Electrical Auxiliary Building (EAB) and Isolation Valve Cubicle (IVC). HL&P's Incident Review Comittee (IRC) determined that both the items should be considered as part of a generic concern regarding the use, by Brown & Root, Inc. (B&R) of nonsafety related pneumatic air controllers in safety related HVAC systems.
Subsequent to the July 6,1982 notification Bechtel Power Corporation (BPC) performed an initial review of the overall HVAC design, including consultants' reports, which identified several additional discrepancies under the above generic concern and another mlated item regarding single failure of the supply air mixing box and associated pnetsnatic dampers in the EAB.
II. Description of Incident A.
Nonsafety Pneumatic Air Controllers in Safety Related HVAC Systems All automatic dampers in safety related HVAC systems are operated pneumatically, and the instrument air system serving these dampers is nonsafety related. Following an accident these dampers are not operable and the failure mode is not appropriate in some cases in that it could rtsult in degradation of the system safety functions.
At present, concern for the following areas has been identified:
a)
The pneumatic dagers at the discharge of parallel redundant fans or air handling units fail open during an accident condition, thereby resulting in back flow / recirculation through the standby fan or unit. This condition exists in the following cases:
1.
EAB main supply air handling units. Impact on safety function is partial loss of cooling to safety related equipment and loss of control room pressurization.
2.
IVC supply fans. Impact on safety function is partial loss of cooling to safety related equipment.
3.
Fuel Handling Building (FHB) exhaust fans. Impact on safety function is reduction of exhaust flow with radiological release consequences in r rost-LOCA condition.
4.
Electrical penetration area exhaust fans.
Impact on l
safety function is loss of negative pressure with j
potential radiological release consequences..
b)
The safety function control dampers have been pmvided with nonsafety related pneumatic instrument controls.
1 Consequently, during an accident condition without assumed loss of instrument air, these instrument contrVis could malfunction, resulting in erroneous operation of control dampers. This condition exists in the following cases:
1.
EAB mixing box dampers, resulting in loss of cooling to safety related equipment.
2.
EAB/ Control room pressurintion dampers resulting in loss of pressurization.
3.
Electrical penetration area and FHB pressure control dagers, resulting in loss of negative pressunts.
4.
FHB exhaust air flow control dampers, resulting in reduction of exhaust air and radiological impact.
c)
The pneumatic isolation dampers for EAB outside air intakes fail open during accident conditions, and they do not have redundancy in series. In the case of a toxic gas release condition concurrent with a loss of instrument air, this could result in loss of control room habitability.
B.
Single Failure of Supply Air Mixing Box in EAB The EAB HVAC system consists of a dual duct (hot and cold) supply air system with a mixing box at the supply tenninal for each room. The cooling for each room is controlled by pnetsnatic dagers (one in the hot duct and one in the cold duct, linked together) in the mixing box, which are served by a nonsafety instrunent air system. During emenjency operation with loss of instrument air, these dampers are designed to fail open in the cold duct such that cooling is assured.
The deficiency concem is that in certain areas with more than one train of safety-related equipment, there is no redundancy in the supply air mixing boxes. These areas have been identified as Cable Spreading room 9 El 60'0', Rel Ay room 0 El 35'0" and HVAC rooms 9 El 86'0".
A failurt isociated with the mixing box in these areas would degrade coo..ng and result in higher than design room temperature, which would consequently jeopardize operation of two or more trains of equipment in these areas. A credible failure mode of the mixing box is that the mixing box damper remains stuck closed in the cold duct due to mechanical failure, thereby stopping cooling. -
Further description of this condition is given in the following table:
No. Room Equipment No. of Mixing Impact of a single Trains in boxes serving mixing box damper the room the room failure 1
Cable Spreading B, C 1
No Cooling Room El 60'0" 2
Relay Room A,B,C 2
Cooling reduced by El 35'0"
- 507, 3
HVAC Rm El 86'0" A, B 1
No Cooling III. Corrective Action Modification of the design is under consideration.
Corrective actions will be discussed in futurt reports.
IV. Safety Analysis The potential safety impact of each item described in Section II above is identified with the item. The cause of the incident is considered to be that the existing design concept utilizing nonsafety related pneumatic dampers and controllers did not adequately address the possible failure modes of these devices under accident conditions and the igact of single active failure of mixing boxes in EAB was not fully considered. The overall HVAC system design is currently under detailed evaluation by BPC as part of the Transition Program for the South Texas Prnject (STP).
Resolution of these and other previously identified HVAC problems is scheduled for co@letion prior to release of the affected portions of the systems for continued construction and installation at STP.
d
=s The Light COmpMy nouston iighting & Power RO. Box 1700 Houston Texas 77001 (713)228 9211 October 20, 1982 ST-HL-AE-897 File Number: G12.95 SFN: V-0530 Mr. John T. Collins Regional Administrator, Region IV Nuclear Regulatory Commission 611 Ryan Plaza Dr., Suite 1000 Arlington, Texas 76012
Dear Mr. Collins:
South Texas Project Units 1 & 2 Docket Nos. STN 50-498, STN 50-499 Final Report Concerning Heatino, Ventilation and Air Conditioning Design On May 8, 1981, pursuant to 10CFR50.55 (e), Houston Lighting & Power Company (HL&P) notified your office of an item concerning the consideration of certain faulted condition heat loads in the design of portions of the Heating, Ventilation and Air Conditioning (HVAC) system. Based on an assessment of preliminary thermal environnental data, it was identified that certain spaces and cubicles within the Mechanical-Electrical Auxiliary Building (MEAB) and the Fuel Handling Building (FHB) would likely require additional HVAC capacity.
On July 6, 1982, HL&P expanded the scope of this iten to include two items regarding the use of fail open isolation dampers in the HVAC design and single failure criteria in the EAB supply air mixing box. There was a concern that the failure mode of isolation dampers had not been adequately assessed by Brown & Root, Inc. (B&R) in the HVAC design.
Attached is our Final Report regarding these items which provides the results of the evaluation that has been performed.
l l
1 l
Houston Lighting & Power Company Page 2 If you should have any questions concerning this item, please contact Mr. Michael E. Powell at (713) 877-3281.
Very truly yours,
- 4. / 4L c A
l r ev 4
G W. Oprea, Jr.
Executive Vice President MEP/mg Attachment o#
4 l
1 1
4 d
1 i
F r--
---m
Houston Lighting & Power Company October 20, 1982 cc:
G. W. Oprea, Jr.
ST-HL-AE-897 J. H. Goldberg File Number: G12.95 J. G. Dewease Page 3 J. D. Parsons D. G. Barker M. R. Wisenburg R. A. Frazar J. W. Williams R. J. Maroni J. E. Geiger H. A. Walker S. M. Dew J. T. Collins (NRC)
D. E. Sells (NRC)
W. M. Hill, Jr.
(NRC)
M. D. Schwarz (Baker & Botts)
R. Gordon Gooch (Baker & Botts)
J. R. Newman (Lowenstein, Newman, Reis, & Axelrad)
STP RMS Director, Office of Inspection & Enforcement Nuclear Regulatory Commission Washington, D. C. 20555 G. W. Muench/R. L. Range Charles Bechhoefer, Esquire Central Power & Light Company Chairman, Atomic Safety & Licensing Board P. O. Box 2121 U. S. Nuclear Regulatory Commission Corpus Christi, Texas 78403 Washington, D. C.
20555 H. L. Peterson/G. Pokorny Dr. James C. Lamb, III City of Austin 313 Woodhaven Roa1 P. O. Box 1088 Chapel Hill, North Carolina 27514 Austin, Texas 78767 J. B. Poston/A. vonRosenberg Mr. Ernest E. Hill City Public Service Board Lawrence Livermore Laboratory P. O. Box 1771 University of California San Antonio, Texas 78296 P. O. Box 808, L-46 Livermore, California 94550 Brian E. Berwick, Esquire William S. Jordan, III Assistant Attorney General Harmon & Weiss for the State of Texas 1725 I Street, N. W.
P. O. Box 12548 Suite 506 t
l Capitol Station Washington, D. C.
Lanny Sinkin Citizens for Equitable Utilities, Inc.
Citizens Concerned About Nuclear Power c/o Ms. Peggy Buchorn 5106 Casa Oro Route 1 Box 1684 San Antonio, Texas 78233 Brazoria, Texas 77422 Jay Gutierrez, Esquire Hearing Attorney Office of the Executive Legal Director U. S. Nuclear Regulatory Commission Washington, D. C.
20555 Revision Date 10-18-82
FINAL REPORT CONCERNING HEATING, VENTILATION, AND AIR CONDITIONING DESIGN INTRODUCTION This final report presents an evaluation and corrective action for the following HVAC design deficiencies that have been reported pursuant to 10CFR50.55(e).
A.
Lack of safety-related cooling in certain areas of Mechanical-Electrical Auxiliary Building and Fuel Handling Building.
B.
Nonsafety-related pneumatic air controllers in safety-related HVAC systems.
C.
Single failure of supply air mixing box in Electrical Auxiliary Building.
The above deficiencies have been reported to the NRC on May 8, 1981 and July 6, 1982. Five interim reports have been submitted to the NRC regarding the HVAC design.
1
4 i
DEFICIENCY A Lack of safety-related cooling in certain areas of Mechanical-Electrical Auxiliary Building and Fuel Handling Building.
I.
SUMMARY
A review was perfomed to determine if safety-related HVAC service was provided for all safety-related equipment. Several areas in the Mechanical and Electrical Auxiliary Building (MAB and EAB) and Fuel Handling Building (FHB)'with safety-related equipment have bean identified as not having safety-related cooling.
It has also been identified that the existing cooling capacity of EAB HVAC system is not sufficient to meet the actual-cooling load, since the system was sized on the basis of preliminary calculations. These results are the conclusion of an extensive review by
- Bechtel of turnover documentation in accordance with the transition procedure.
Corrective action is required to maintain the room anbient temperatures below the equipment qualification temperature and thereby prevent failure of safety-related equipment.
This deficiency is being resolved by adding new chillers to the existing EAB i
chilled water system, which serves as a centralized essential chilled water system, to provide the additional safety-related cooling to the above
~
identified areas. New chilled water air handling units will be provided for all areas identified as not having safety-related cooling.
II.
DESCRIPTION OF DEFICIENCY In April,'1980, HL&P sent a letter to Brown & Root (B&R) which questioned the absence of safety-related HVAC service for the hot shutdown panel and the hydrogen monitors located in radwaste control room, and called for a review of safety-related HVAC requirements in other areas as well. A review was performed by B&R to determine if safety-related HVAC service was adequate for all safety-related equipment.
In addition to the radwaste control room, several other areas were identified as re On May 8,1981, pursuant to 10CFR50.55(e) quiring safety-related HVAC service.
I
, HL&P notified NRC of this deficiency.
l Subsequently, a detailed review was performed by B&R.
In addition, in order to expedite resolution of this item, two consultants were engaged by B&R to perform system review, evaluation, and design recommendation activities. The reports by the consultants and B&R were included in the transition work packages transmitted to Bechtel. Bechtel has now completed the review of the overall STP HVAC design including the consultant's reports. Based oi, this l
review, Bechtel confirmed the areas identified by B&R and the consultants as requiring safety-related HVAC service and identified a lack of EAB cooling capacity.
2
DISCUSSION OF FINDINGS:
Finding (1)
Bechtel conducted a multi-discipline review of HVAC system requirements.
From this review, safet'-related equipment was confirtned to be provided with safety-related cooling witn tne exception of areas as listed in Table-1.
Table-1 also identifies the " user" equipment and associated trains in each a rea.
The addition of safety-related HVAC service to areas listed in Table-1 is based on the requirement to maintain temperatures below the environmental qualification parameters of any safety-related equipment. New safety-related HVAC systems will provide the required environment.
The rationale for selecting each area listed in Table-1 is listed below.
(a) Electrical Penetration Spaces in EAB In addition to class IE cables, this area has the containment high range area radiation nonitors and 15KV reactor coolant pump class 1E cubicles. Presently there is no provision for cooling in this area.
(b) Radwaste Control Room in MAB Hydrogen monitors for the containment atmosphere are located in the radwaste control room and are required to operate following an accident. B&R had also identified the auxiliary shutdown panel which was previously located in the radwaste control room; however, this shutdown panel is now being relocated in an EAB area with existing safety-related HVAC service.
The radwaste control room is presently served by the nonsafety-related MAB main supply and exhaust system powered with non-1E electrical power, which may not be available following an accident.
(c) Boric Acid Transfer Pump and CVCS Valve Cubicles in MAB The boric acid transfer pumps and CVCS valves are used to supply boric acid from the boric acid tanks to the CVCS charging pumps for reactor coolant boration. Boration is required for safe shutdown.
The boric acid transfer pump and CVCS valve cubicles are i
presently served by the same nonsafety-related MAB main supply l
and exhaust system as in (b) above.
l 3
(d) Reactor Make-up Water Pump Cubicle in MAB These pumps could be required for emergency replenishment of water in the Spent Fuel Pool, and in the Component Cooling Water System (CCWS) surge tank if the Demineralized Water System is not available.
The reactor make-up water pump cubicle is presently served by the same nonsafety-related MAB main supply and exhaust system asin(b)above.
(e) Spent Fuel Pool Cooling Pump Cubicles The Spent Fuel Pcol Cooling and Cleanup System (SFPCCS) pumps are required tu remove decay heat g;nerated by spent fuel assemblies stored in the spent fuel pool. The pumps are required at some time following a loss of offsite power and are powered by a class 1E power supply.
The spent fuel pool cooling pump cubicles are presently cooled by the nonsafety-related FHB supply system with non-1E electrical power, which may not be available following an i
accident.
(f) ContainmentIsolationYalveCubiclesinFHB 4
1 The containment isolation valves that are open for emergency core cooling and for containment spray (See Table-1) have electric motor drive actuators and have a safety function to perfom after the accident. All the valves must close eventually for containment isolation, whether at the end of recirculation phase or for isolating an out-of-service train.
The qualification temperature of the valve actuator should not be exceeded before its safety function is required.
The three encapsulated isolation valves for the containment emergency sumps located in these same cubicles are also vulnerabic to excessive environmental temperatures. These nomally closed valves must open at the end of the safety injection phase so the recirculation phase can begin, then close after the recirculation phase is completed for l
containment isolation. The valves are supplied by Westinghouse, and the actuators have a qualification temperature corresponding to post-LOCA inside containment l
parameters. These areas are presently served by the nonsafety-related FHB HVAC system which may not be available following an accident.
(g) Electrical Auxiliary Building Chiller Area in MAB The EAB chillers are safety-related and are required to operate following an accident to maintain the design environmental conditions in the control room envelope and the remaining EAB.
4
1 t
This chiller area is presently served by the nonsafety-related l
MAB main supply and exhaust system, which may not be available i
following an accident.
(h) Electrical Penetration Exhaust Fan Area The electrical penetration area exhaust is presently classified as a safety-related system. The exhaust fan area, located in the MAB is served by the nonsafety-related MAB main supply and exhaust system, which may not be available following an accident. However, the' exhaust fan system is going to be downgraded to nonsafety-related as a result of HVAC systen design changes and as such does not require safety-related HVAC services.
Finding (2)
As part of the transition work package EM-551 from B&R, Bechtel did a detailed review of the EAB cooling loads. As a result of this review it has been determined that the actual building cooling load is higher than the existing system capacity. Originally the system was sized on the basis of preliminary calculations by B&R. Subsequently these calculations were reperforwed by one of the two consultants engaged by B&R. A review of these calculations indicates that the system cooling capacity is undersi:ed.
Cooling load calculations by Bechtel are presently underway for the purpose of equipment sizing.
III.
CORRECTIVE ACTION A conceptual design to correct deficiency Finding (1) above was proposed in the B&R and consultants reports. Bechtel has reviewed the proposed design and agrees with the basic concept of providing safety-related chilled water and local air handling units to provide cooling in each room identified in 4
Table-1. However, the overall chilled water system design developed by Bechtel is different from the B&R/ consultants proposed desi designed to correct both the above deficiencies, findings (gn, since it is1) and (2), and t resolve some of the open items in the B&R/ consultants repnets. Following is a description of 'he Bechtel design for corrective action to resolve the subject deficient./.
System Description
New chillers will be added to the existing EAB chillers to provide a centralized essential chilled water system. This system would serve the cooling load requirements of the EAB and all the areas identified in Table-1 during norwal and emergency conditions.
The chilled water system will consist of three 50% trains A, B, and C, with two chillers per train, one existing EAB chiller and a second, new chiller in parallel. The new chillers will be water cooled with ECW, and served by the emergency power, just as the existing EAB chillers. The new chillers and h
5
. ~..
pumps will be located in the same area as the existing EAB chillers at El.
10'-0" of MAB. Each chiller train will be completely independent and physically separated from each other. The system will be sized for the maximum cooling load at any given time, with margin to serve future safety-related cooling requirements with two trains operating simultaneously.
The chilled water will be supplied to air handling units which basically consist of a cooling coil and supply fan. The number of air handling units and associated trains in each area will be based on the " user" equipment trains in the respective area, to account for single failure and provide redundancy, as given in Table-1.
IV.
RECURRENCE CONTROL The subject deficiencies mainly resulted from lack of interface with the
" user" disciplines. The HVAC system design did not incorporate all the
" user" requirements nf safety-related cooling and cooling loads.
Bechtel will conduct future project activities in a manner which should preclude the types of deficiencies resulting from interdiscipline information exchange. This will be accomplished by the use of Bechtel Engineering Department Procedures which will be followed in the performance of future design activities for the project. These procedures are based upon those used effectively for engineering activities performed at other major nuclear projects. The effective use of these procedures is assured by the on-project indoctrination, training, monitoring, and the Quality Assurance Audit Program.
V.
SAFETY ANALYSIS If this deficiency had remained uncorrected, the environmental temperature in the subject areas (listed in Table-1 and EAB, including control room envelope) could have increased above the equipment qualification and/or habitability tenperature for the control room, resulting in a possible failure of equipment or loss of control room habitability. Since the equipment in the subject areas is safety-related, this deficiency could have jeopardized the safe operation of the plant.
DEFICIENCY B Nonsafety Pneumatic Air Controllers in Safety-Related HVAC Systems I.
SUMMARY
All automatic dampers in safety-related HVAC systens are operated pneumatically, and the instrument air system serving these dampers is nonsafety-related.
This deficiency will be resolved by providing danpers that are operable following an accident or by providing a fixed balanced system to meet the building pressure requirements.
6 1
l I
The cause of this deficiency is that the existing design concept utilizing nonsafety-related pneumatic dampers and controllers did not adequately 4
address the possible failure modes of these devices under accident conditions.
II.
DESCRIPTION OF DEFICIENCY On July 6,1982, pursuant to 10CFR50.55(e), Houston Lighting & Power Company (HL&P) notified the NRC of two items regarding the use of fail open pneumatic dampers at the discharge of redundant supply fans. Following an accident these dampers are assumed to be inoperable and the failure mode (fail-open or closed).is not appropriate in certain cases where it could result in l
degradation of the system safety functions, as described below.
~
Pneumatic fail open dampers at the discharge of redundant fans 1.
in parallel, resulting in t,ack flow through redundant fan.
2.
Pneumatic modulating control dampers for air flow or building pressure control, resulting in radiological impact or loss of building pressure, respectively.
3.
The pneumatic isolation darpers for EAB outside air intakes fail open during accident conditions, and do not have redundancy in series.
In the case of a toxic gas release condition concurrent with a loss of instrumer.t air, this could result in loss of control room habitability.
HL&P's Incident Review Committee (IRC) detertnined that these items should be considered as part of a generic concern regarding the use of j
nonsafety-related pneumatic air controllers in safety-related HVAC systems.
This was followed by a Fifth Interim report which addressed all the deficiencies identified under the above generic concern, based on an initial review by Bechtel of the overall HVAC design. Subsequently Bechtel has completed the review, which confirms the findings reported in the Fifth Interim report. See the interim report fer description of the findings and safety analysis.
III.
CORRECTIVE ACTION With reference to the Fifth Interim report the following are the corrective actions to resolve the subject deficiencies.
A.
Nonsafety-Related Pneumatic Air Controllers in Safety-Related HVAC Systems All automatic dampers in safety-related HVAC systems are operated pneumatically, and the instrument air system serving these dampers is nonsafety-related. Following an accident these dampers are not operable and the failure mode is not appropriate in some cases since it could result in degradation of the system safety functions. At present, concern for the following areas has been identified:
{
7
x2.>
w_
y 4
l L
i a)
The oneumatic dampers at the discharge of parallel redundant fans or air handling units fail open o'uring an accident condition, thereby resulting in back flow / recirculation through the standby
' fan or unit. This condition exists in the following cases:
1.
EAB main supply air handling units. Impact on safety function is partial loss of cooling to safety-related equipment and loss of control room pressurization.
2.
IVC supply fans.
Impact on safety function is partial loss of cooling to safety-related equipment.
3.
Fuel Handling Building (FHB) exhaust fans.
Impact on safety function is reduction of exhaust flow with potential radiological release consequences in a post-LOCA condition.
4.
Electrical penetration area exhaust fans. Backflow /recircu-tion through the standby fan could result in the current destgr., however the electrical penetration area exhaust system is be.ing down-graded to nonsafety-related, since it is not required to maintain the negative pressure in the penetration space as a safety function.
Corrective Action for Item A(a)1 to 4:
Pneumatic dupers at the discharge of parallel redundant fans or air handling units in all cases reported will be replaced with an isolation damper with the correct failure mode. These dampers will remain closed when the corresponding fan is not operating and open when the fan is energized, thereby preventing backflow through the standby fan, b)
The safety-related control dampers have been provided with nonsafety-related pneumatic instrument controls. Consequently, I
during an accident condition without assumed loss of instrument air, these instrument controls could malfunction, resulting in erroneous operation of control dampers. This condition exists in the following cases:
1.
EAB mixing box dampers resulting in loss of cooling to safety-related equipment.
l 2.
EAB/ Control room pressurization dampers resulting in loss of pressurization.
3.
Electrical penetration area and FHB pressure control dampers i
resulting in loss of negative pressures.
4.
FHB exhaust air flow control dampers resulting in reduction of exhaust air and potentially increased radiological impact.
Corrective Action for Item A(b)1 - Mixing box dampers:
The mixing boxes will be deleted as described in the corrective action for Deficiency C.
8
Corrective Action for Item A(b)2 - Pressurization dampers:
The make-up air to the control room system will be balanced to provide the required minimum outside air to maintain positive pressure.
Corrective Action for Item A(b)3 - Control dampers:
The electrical penetration area exhaust system is being down-graded to i
nonsafety-related, since it is not required to maintain the negative pressure in the penetration space as a safety function.
l The make-up air to the Fuel Handling Buildin.g will be balanced to provide the required airflow rates to maintain negative pressure.
Corrective Action for Item A(b)4 - Exhaust control dampers:
The FHB exhaust fans will be provided with backdraft dampers at the fan discharge thereby preventing backflow.
4 c)
The pneumatic isolation 6ampers for EAB outside air intakes fail open during accident conditions, and do not have redundancy in series.
In the case of a toxic gas release condition concurrent with a loss of instrument air, this could result in Icss of control room habitability.
Corrective Action for Item A(c):
~
The EAB outside air intake dampe s will be provided with safety-related actuators designed to place the lampers in the fail-closed mode.
Following an accident, dampers can be opened for emergency plant operation.
IV.
RECURRENCE CONTROL In the future design process full consideration will be given to the failure modes of pneumatic dampers, when using them in safety-related systems. Thi's will be accomplished by the use of Bechtel Engineering Department Procedures which will be followed in the performance of future design activities for the project. These procedures are based upon those used effectively for engineering activities perfonned at other major nuclear projects. The effective use of these procedures is assured by the on-project indoctrination, training, monitoring, and the Quality Assurance Audit j
Program.
DEFICIENCY C Sincle Failure of Supply Air Mixino Box in Electrical Auxiliary Building (EAl) l
\\#
9 l
l
I.
SUMMARY
The EAB HVAC system consists of a dual duct (hot and cold) supply air system with a mixing box at the supply terminal for each room. The deficiency of concern is that, in certain areas with more than one train of safety-related equipment, there is no redundancy in the supply air mixing boxes. A failure associated with the mixing box in these areas would degrade cooling and result in temperatures higher than that to which equipment has been qualified. This could jeopardize operation of two or more trains of equipment in these areas.
This deficiency is being resolved by replacing the dual duct concept with single supply air duct. This involves deleting the mixing boxes and therefore eliminating the possibility of the subject active failure.
II.
DESCRIPTION OF DEFICIENCY This deficiency was identified along with " Deficiency B" as a result of initial BPC review of overall HVAC design, and reported in the Fifth Interim report. Subsequently BPC has completed the review, which confirms the findings reported. See the interim report for description of the findings and safety analysis.
III.
CORRECTIVE ACTION With reference to the Fifth Interim Report, this deficiency will be resolved by deleting the EAB HVAC dual duct concept and providing a single cold supply air duct. This involves deleting the mixing boxes and hot duct in the existing design. With deletion of the mixing boxes there is no active component in the supply duct system, which eliminates the possibility of the subject active failure.
The above corrective action involves complete revision of the existing duct layout in EAB and purchase of new reheat coils for certain areas reouiring close temperature control. The reheat coils need not be safety-related; however, they will be provided with safety-related isolation controls.
IV.
RECURRENCE CONTROL The recurrence control is similar to that for Deficiency B.
In addition, consideration of single active failure criteria is part of the HVAC system design criteria.
i 10
TABLE-l NEW SAFETV-RELATED HVAC COOLING REQUIREMENT
~
+
Location (1)
U3tR LQUIP Ut5IGN RM NEW LUULING URII5 BT TRAIN 5 USLR LQUlFritMI U3tR LQUIP QUALIF BLOG. ROOM f ELEV A00M NAME TRAINS TEMP.*F
~A B
C LOCATED IN ROOH TEMP *F Norwal Accident EA8 001 10'0* Electrical Penetration Space A
104 1-1001 201 35'0* Electrical Penetration Space B
104 1-10d1
- 1. High range area 120 120 radiation monitors 301 60'0* ElectricalJenetration Space C
104 1-1001 2.15KV reactor coolant 104 104 pump Class IE cubicles
- 3. Class IE Cables 104 104 MAB 033 10'O' CVCS Valve Cubicle A,8 104 1-1001 1-1031 CVCS Valves; (2) 104 104 044 10'0* CVCS Valve Cubicle C
104 1-1001 ICV 218. ICVil38, 226 41'0* CVCS Valve Cubicle A,C 104 1 1001 1-1001 ICVil2C.
l ICVil2B,ICVil3A.
067-1 10'0* EA8 Chiller Area A
120 1-1001 EAB Chillers & New 120 120
[
067-2 10'0*
EA8 Chiller Area B
120 1 1001 Safety-Related Chillers j
067-3 10'0* EA8 Chtller Area C
120 1-1001 018 20'0* Boric Acid Transfer Pu g Cubicle A,C 104 1-1001 1-1001 Borte Acid Transfer 120 120 l
Pugs 062 20'0* Reactor Make-up Water Pugs A,8 104 1-1001 1-1001 Reactor Make-up Water 120 120 Cubicle Pugs 217 41'0* Radwaste Control Room A,C 104 1-501 1-501 1-501(3)
H Monitoring Equfp-104 104 ednt FHB 007 4'0*
Isolation Valve Cubicle A
104 1-1001 Containment Isolation 104 104 008 4'0*
Isolation Valve Cubicle B
104 1-1001 Valves (2):
009 4'0*
Isolation Valve Cubicle C
104 1-1001 15I004 A.B.C % 511
+
151018 A,B.C LLH5ll l IC5001 A,B,0 LCS) 151016 A B.C 104 168 (4) 106 21'11* Spent Fuel Pool Pump Room B
104 1-1001 5FPCCS Pugs 104 104 107 21'11* Spent b e Pool Pump Room C
104 1-1001 NOTES 1Tnoom numbers Itsted are as shown on Bechtel architectural drawings.
L2 l
Valve numbers listed are as shown on Bechtel P&lDs. Valves are supplied by Westinghouse.
[4J;i Consideration will be given to providing two 1001 units, if required due to space Ilmitation.
1 3 Based on Westinghouse Spectitcation G-952850-0 for 100,000 seconds, and 285'F at 100 seconds Post-LOCA.
s
2
?T l
The Light Company a-sm ug%@~ m wa u nos
.wn,une,.m May 17, 1984 ST-HL-AE-1084 i
File No.: G12.95 Mr. John T. Collins Regional Administrator, Region IV Nuclear Regulatory Cormission 611 Ryan Plaza Dr., Suite 1000 Arlington, Texas 76012
Dear Mr. Collins:
South Te>is Project Units 1 & 2 Docket Nos. STN 50-498, STN 50-499 Supplemental Report Concerning the Heating, Ventilation and Air Conditioning Design Deficiency On May 8, 1981, pursuant to 10CFR50.55(e), Houston Lighting & Power Company (HL&P) notified your office of an item concerning the consideration of certain faulted condition heat loads in the ' design of portions of the Heating, Ventilation and Air Conditioning (HVAC) system. Based on an assessment of preliminary thennal environmental data, it was determined that certain spaces and cubicles within the Mechanical-Electrical Auxiliary Building (MEAB) and the Fuel Handling Building (FHB) would likely require additional HVAC capacity.
On July 6, 1982, HL&P expanded the scope of this item to include two additional items: use of fail open isolation dampers in the HVAC design and single failure criteria in the EAB supply air mixing box. There was a concern that the failure mode of isolation dampers had not been adequately assessed by Brown & Root, Inc. (B&R) in the HVAC design.
On October 20, 1982, HL&P submitted the Final Report on these items.
The statement in the final report indicating that all safety-related equipment has safety-related cooling is incomplete. The design criteria is to qualify all safety-related equipment for the environmental conditions in which it must perform its safety function. Where controls, instrumentation, valves, etc., are not served by safety-related cooling, these components will be qualified to the most severe environmental conditions to which they may be exposed.
j W2/NRC2/f
\\
o Houston Lighting & Power Company May 17, 1984 ST-HL-AE-1084 File No.: G12.95 Page 2 Due to design changes made subsequent to the submittal of our Final Report, the infomation presented below modifies and updates that report.
(1) Paragraph 1(b) of Findings for Deficiency (A): The containment atmosphere hydrogen monitors are now being relocated outside the radwaste control room to reduce any unnecessary personnel exposure that might arise from the air sample filter and lines.
Safety-related HVAC cooling will be provided to the hydrogen monitors in their new location on elevation 60 feet of the MEAB.
(2) Corrective Action for Item A(b)2 of Deficiency B: Each makeup air pressurizer damper will be driven by an electro-hydraulic actuator which is controlled by a manual loading station within the main control room. The damper will automatically open to a preset position to pemit pressurization of the control room envelope.
During operation of the makeup air filtration system, the operator can maintain positive pressure by manually adjusting the damper to accomodate filter loading conditions.
(3) Corrective Action for Deficiency C: As stated in the Final Report, this deficiency will now be resolved by deleting the EAB HVAC dual duct concept and providing a single cold supply air duct. This involves deleting the mixing boxes and hot duct in the existing design. With deletion of the mixing boxes there will be no active component to isolate in the supply duct distribution system downstream of the air handling unit safety isolation dampers, thus l
eliminating the possibility of the subject active failure.
The above corrective action involves complete revision of the existing duct layout in EAB and purchase of new reheat coils for certain areas requiring close temperature control. The reheat coils for the EAB (except IE battery rooms) need not be safety-related; however, they will be provided with safety-related isolation controls. Reheat coils for 1E battery rooms will be safety-related to maintain battery room temperature conditions.
This inforwation supplements the Final Report concerning this item.
If you should have any questions concerning this item, please contact Mr. Michael E. Powell at (713) 993-1328.
Very t 1 yours, pre.
t Exec tive ce President MEP/ mpg Attachment W2/NRC2/f
[
i May 17, 1984 Houston Lighting & Power Company i N
.b r G12.95 Page 3 cc:
Darrell G. Eisenhut, Director Brian E. Berwick, Esquire Division of Licensing Assistant Attorney General for Office of Nuclear Reactor Regulation the State of Texas U.S. Nuclear Regulatory Comission P. O. Box 12548, Capitol Station Washington, DC 20555 Austin, TX 78711 Victor Nerses Project Manager Lanny Sinkin U.S. Nuclear Regulatory Comission Citizens Concerned About Nuclear Power 7920 Norfolk Avenue 114 W. 7th, Suite 220 Bethesda, MD 20016 Austin, TX 78701 D. P. Tomlinson Robert G. Perlis, Esquire Resident Inspector / South Texas Project Hearing Attorney c/o U.S. Nuclear Regulatory Comission Office of the Executive Legal Director P. O. Box 910 U.S. Nuclear Regulatory Comission Bay City TX 77414 Washington, DC 20555 M. D. Schwarz, Jr., Esquire Charles Bechhoefer, Esquire Baker & Botts Chairman, Atomic Safety & Licensing Board One Shell Plaza U.S. Nuclear Regulatory Comission Houston, TX 77002 Washington, DC 20555 J. R. Newnan, Esquire Dr. James C. Lamb, III Newman & Holtzinger, P.C.
313 Woodhaven Road 1025 Connecticut Avenue, N.W.
Chapel Hill, NC 27514 Washington, DC 20036 Judge Ernest E. Hill Director, Office of Inspection Hill Associates and Enforcement 210 Montego Drive U.S. Nuclear Regulatory Comission Danville, CA 94526 Washington, DC 20555 E. R. Brooks /R. L. Range William S. Jordan, III, Esquire Central Power & Light Company Harmon & Weiss P. O. Box 2121 1725 I Street, N.W.
Corpus Christi, TX 78403 Suite 506 Washington, DC 20006 H. L. Peterson/G. Pokorny City of Austin Citizens for Equitable Utilities, Inc.
P. O. Box 1088 c/o Ms. Peggy Buchorn Austin, TX 78767 Route 1. Box 1684 Brazoria, TX 77422 J. B. Poston/A. vonRosenberg City Public Service Board P. O. Box 1771 San Antonio, TX 78296 Revised 04/03/84
,