ML20035E889
| ML20035E889 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 04/16/1993 |
| From: | George Thomas DUQUESNE LIGHT CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| RTR-REGGD-01.075, RTR-REGGD-1.075 GL-92-08, GL-92-8, NUDOCS 9304200028 | |
| Download: ML20035E889 (6) | |
Text
. =. -
9
{
Beaver Valley Power Station Shippingport. PA 15077-0004 l
1412) 393-520S (412) f 43-8369 FAX GEORGE S. THOMAS April 16,1993 l
Division Vice Pres 6 dent Nuclear Services Nuclear Power Dmason F
i U.
S. Nuclear Regulatory Commission Attn:
Document Control Desk Washington, DC 20555
[
i
Subject:
Beaver Valley Power Station, Unit No. 1-and No. 2 BV-1 Docket No. 50-334, License No. DPR-66 BV-2 Docket No. 50-412, License No. NPF ~73 i
NRC Generic Letter 92-08, Thermo-Lag 330-1 Fire Barriers
.l i
Provided in Enclosure 1
is a
response to NRC Generic Letter 92-08, "Thermo-Lag 330-1 Fire Barriers" for the Beaver Valley Power Station Unit 1 and Unit 2.
Generic Letter 92-08 provides an overview of developments of the Thermo-Lag fire barrier issue, and requests information pursuant to 10 CFR 50.54 (f) relative to installed Thermo-Lag barriers.
Should you have any questions regarding this information or i
require additional information, please contact John Maracek at (412) 393-5232.
I l
Sincerely, (8
M G.
S. Thomas Attachment cc: Mr.
L. W. Rossbach, Sr. Resident Inspector Mr. T. T. Martin, NRC Region I Administrator
.Mr.
G.
E.
Edison, Project Manager j
Mr. W.
P. Dornsife, Director BRP/ DER Mr. R. J. Barkanic, BRP/ DER i
Mr. M. L. Bowling (VEPCO) i l
I' 9304200028 930416 p.
i PDR ADOCK 03000334 i,,
p PDR
?-
AFFIDAVIT COMMONWEALTH OF PENNSYLVANIA)
) SS:
COUNTY OF BEAVER
)
Subject:
Beaver Valley Power Station, Unit No. 1 and No. 2 BV-1 Docket No. 50-334, License No. DPR-66 BV-2 Docket No. 50-412, License No. NPF-73 Thermo-Lag 330-1 Fire Barriers l
Before me, the undersigned notary public, in and for the County l
and Commonwealth aforesaid, this day personally appeared George S.
- Thomas, to me known, who being duly sworn according to law, deposes and says that he is Division Vice President, Nuclear Services of the Nuclear Power Division, Duquesne Light Company, he is duly authorized to execute and file the foregoing submittal on behalf of said
- Company, and the statements set forth in the submittal are true and correct to the best of his knowledge, information and belief.
M d*ycb "S
~ 6 e o r g e' S. Thomas Subscribed and sworn to before me onthis/
day of sLL/'
x wa a Awk
~
tary Iublic /
f Tramy A Ba=ok,Nowy Ptd ShopiW Boro.Scaww Cairty f4 Cunmsson Expies/sug 16,1933 Mct, PenrcWana Assx!10n o' N 0 103
Responze To NRC Generic Letter 92-08 For Beaver Valley Power Station Unit 1 and Unit 2 ENCLOSURE 1 Generic Letter 92-08 requested that licensees address various items relative to Thermo-Lag 330-1 Fire Barriers.
This enclosure provides specific responses to each of the items requested.
1.
State whether Thermo-Lag 330-1 barriers are relied upon (a) to meet 10 CFR 50.48, to achieve physical independence of electrical
- systems, (b) to meet a condition of a plant's operating license, or (c) to satisfy a licensing commitment.
If applicable, state that Thermo-Lag 330-1 is not used at the facility.
This generic letter applies to all 1-hour and all 3-hour Thermo-Lag 330-1 materials and barrier systems assembled by any assembly method such as by assembling preformed panels and conduit shapes, as well as spray, trowel and brush-on applications.
Response
As previously identified in our response to NRC Bulletin 92-01 and Supplement No.
1, Thermo-Lag 330-1 barriers are relied upon at BVPS Unit 1 and BVPS Unit 2 to comply with the fire protection requirements of 10 CFR 50.48 for protection of safe shutdown components and electrical systems to satisfy NRC requirements.
Thermo-Lag was not utilized at our BVPS Unit 1 and BVPS Unit 2 facilities for Regulatory Guide 1.75 applications.
Neither Unit utilizes Thermo-Lag as a radiant energy shield inside containment areas.
2.
(a)
State whether or not the licensee has qualified the Thermo-Lag 330-1 fire barriers by conducting fire endurance tests in accordance with the NRC's requirements and guidance or licensing commitments.
Response
Thermo-Lag 330-1 fire barrier systems installed at BVPS Unit 1
and BVPS Unit 2 were initially qualified to industry standards applicable at that time.
Subsequently, NRC Bulletin 92-01 and Supplement No. 1 reported the existing Thermo-Lag barrier qualification testing invalid-and the fire resistance rating of the Thermo-Lag material indeterminate.
. ~_
i f
- (Cont'd)
Page 2 of 4 i
2.
(b)
State (1) whether or not the fire barrier configurations installed in the plant represent the materials, workmanship, j
methods of
- assembly, dimensions, and configurations of the l
qualification test assembly configurations; and (2) whether-or not the licensee has. evaluated any deviations from the i
tested configurations.
j
Response
Our installed Thermo-Lag 330-1 fire barrier systems are j
based on manufacturer's design and installation l
instructions.
The existing qualification tests were i
determined invalid per NRC Bulletin-92-01 and Supplement No.
1 to the Bulletin.
Fire barriers in the affected areas i
were declared potentially inoperable and hourly fire watch l
patrols were.
instituted as an interim measure until permanent
' corrective actions can be implemented.
l Appropriate actions to restore fire barrier operability are being developed through an industry program being coordinated by NUMARC.
l Engineering evaluations have been developed for existing fire rated assemblies located in the cable-mezzanine area of i
BVPS-Unit l'
which utilize Thermo-Lag 330-1.
. The configurations have been reviewed by a
qualified fire i
protection engineer in accordance with NRC Generic Letter l
86-10 and found to provide an equivalent level of protection i
to that of a tested configuration.
2.
(c)
State (1) whether or not the as-built Thermo-Lag 330-1 barrier configurations are consistent 'with the barrier configurations used during the ampacity derating ' tests relied upon by the licensee for the 'ampacity derating factors used for all raceways protected by Thermo-Lag 330-1 (for fire protection of safe shutdown capability or to achieve physical independence of electrical systems) and (2) whether or not the ampacity derating test results relied upon by the licensee are correct and applicable to the plant design.
Response
The original -acpacity derating factors used for cable in conduit protected with Thermo-Lag 330-1 fire barrier systems were-based on the nanufacturer's recommendations of 3% for a one hour barrier (1/2" thickness) and 11% for a three hour barrier (1"
thickness).
These derating factors were-supported by testing which appears in TSI Technical Note 111781
- titled,
" Engineering Report On Ampacity Test For_600 Volt Power Cables Installed In A Five Foot Length Of Two Inch Conduit Protected With Thermo-Lag 330-1 Subliming Envelope System," Revision 5, dated February, 1985, which is representative of the' installation at our facility.
~
. (Cont'd)
Page'3 of 4 4
l Based on the. recent concerns identified in this generic l
- letter, a
review of the cabling system that' employs the l
Thermo-Lag product was performed and the results are as-l follows:
-j The voltage level classifications at Beaver Valley are*
H - 4160 volt power
{
L - 480 volt power.(intermittent & continuous loads)
K - 480 volt power (intermittent / lighter loads)
C - Control (intermittent 120 VAC & 125 VDC)
X - Instrumentation (signal)
-l The control and instrument level cables were not' considered j
for derating due to the nature of their service and the resulting negligible heat release from 'these cables.
An evaluation-of the original derating calculation was.
i performed to address the higher derating factors referenced-i in the generic letter (i.e.,
37.4% for one hour and 38.9%.
for three hours) for potential impact on the installed 4160
~
and 480 volt power cables.
Results revealed that all'of the
{
"K" level and most of the "L" "H"
level power cables had sufficient design margin to accommodate the higher derating' factors.
"L" "H" level power cables that are intermittent I
loading were not considered.
Three- (3). cases required further evaluation and -the Neher-McGrath method, utilizing I
the heat transfer characteristics of.the materials in the cable-conduit assembly (rather-than using derating i
multiplier factors),
was used for the-evaluation.
All
(
cables were determined to have adequate capacity after'the derating assessment.
l l
The cable derating issue will' be re-evaluated after the results of the pending NUM3RC derating testing.
This l
proposed test will utilize the methodology of IEEE Standard I
- P848, (Draft)
" Procedure for the Determination of the Ampacity Derating of Fire Protected Cables."
l i
3.
With respect to any answer to items 2(a), 2(b), or 2(c) above in the
- negative, (a) describe all corrective actions needed and i
include a
schedule by which such actions shall be completed and
~
(b) _ describe all compensatory measures taken in accordance with j
the technical specifications or administrative controls.
i'
Response
Appropriate measures to restore fire barrier operability are being developed through an industry program coordinated by NUMARC.
Plant specific ~ engineering evaluations are being developed to verify compliance with NRC regulatory requirements for Thermo-Lag 330-1 fire barrier systems.
Interim compensatory.
I measures previously identified in our response to Bulletin 92-01 and Supplement 1 will remain in place until permanent corrective actions can be implemented or an engineering evaluation has been developed to verify compliance with NRC regulatory' requirements.
' (Cont'd)
Page 4 of 4 We will continue to work with NUMARC and the industry to develop-a course of action to ensure the fire barriers are capable of performing their design function.
NUMARC's generic test program should bound the configurations used at our facility; however, should corrective actions be required as a result of this testing
- program, the options available will be evaluated or a case by case basis.
Generic ampacity derating factors are being developed under the NUMARC program.
j Specific schedules relative to the NUMARC generic ~ test program will be provided to NRC by NUMARC.
l 4.
List all Thermo-Lag 330-1 barriers for which answers to item 2 cannot be provided in the response due within 120 days from the date of this generic letter, and include a schedule by which such answers shall be provided.
Response
The complete response to item 2 is provided herein.
i l
l i