ML20086C552
| ML20086C552 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 06/26/1995 |
| From: | Schnell D UNION ELECTRIC CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| GL-92-08, GL-92-8, ULNRC-3229, NUDOCS 9507070142 | |
| Download: ML20086C552 (10) | |
Text
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1901 Chouteau Avenue Post Omce Box 149 St. Louis. M.sscun 63166 314-554-2650 UNION
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Etucrme 3une 25, 1995 2";?'t""'"'"'*"'
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U.S. Nuclear Regulatory Commission Attn:
Document Control Mail Station P1-137 Washington, D.C.
20555 Gentlemen:
ULNRC-3229 DOCKET NUMBER 50-443 CALLAWAY PLANT THERMO-LAG 330-1 FIRE BARRIERS
Reference:
1.
Follow-up to the Request for Additional Information Regarding Generic Letter 92-08 Issued Pursuant to 10CFR50.54 (f), dated December 28, 1994 2.
ULNRC-2955, dated February 10, 1994 3.
ULNRC-3116, dated December 19, 1994 4.
ULNRC-3181, dated March 28, 1995 References 2 and 3 provided Union Electric's responses to a request for add itJonal information and a follow-up to the request for aud;-c.ional information regarding Generic Letter 92-08.
heference 1 requests Licensees to provide additional follow-up information to that provided in their previous responses as specified in the enclosure in Sections 1.a, 1.b, 1.c, 2.a, 2.b and 2.c.
Union Electric hereby submits its follow-up response that was committed to in Reference 4 regarding Generic Letter 92-08, "Thermo-Lag 330-1 Fire Barriers",
i pursuant to 10CFR50.54(f).
I Should you have any questions or need additional information concerning this matter, please contact us.
Very tru ou ObObbb Donald F.
Schnell JMC/pir i
Attachment g
9507070142 950626 i
PDR ADDCK 05000483 i
1 PDR
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.' STATE OF MISSOURI
)
)
., COUNTY OF CALIAWAY
)
Donald F. Schnell, of lawful age, being first duly sworn upon oath says that he Senior Vice President-Nuclear and an officer of Union Electric Company; that he has read the foregoing document and knows the content thereof; that he has executed the same for and on behalf of said company with full power and authority to do so; and that the facts therein stated are true ana correct to the best of his knowledge, information and belief.
By
,_ Schnell Donald F.
Senior Vice President Nuclear SUBSCR ED and sworn to before me this y?/c 5 day of k
/L"L 1995.
V Y&&
V' LANA R.JACOBS, Notary Public STATE OF MISSOURI, COUNTY OF CALLAWAY MYCOMulSS60N EXPlRES 114L1996
cc:
T. A. Baxter, Esq.
Shaw, Plttman, Potts & Trowbridge 1
2300 N. Gtreet, N.W.
i Washingto.1, D.C.
20037 M. H. Fletcher Professional Nuclear Consulting, Inc.
19041 Raines Dr Derwood, MD 20855-2432 1
M. J. Farber Chief, Reactor ProjectsSection III A U.S. Nuclear Regulatory Commission Region III i
801 Warrenville Road Lisle, IL 60532-4351 Bruce Bartlett Callaway Resident Office U.S. Regulatory Commission RR#1 Steedman, MO 65077 L. R. Wharton (2)
Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission 1 White Flint, North, Mail Stop 13E21 11555 Rockville Pike Rockville, MD 20852-2738 Manager, Electric Department Missouri Public Service Commission P.O.
Box 360 Jefferson City, MO 65102 Alex Marion i
Nuclear Energy Institute 1776 I St.,
Suite 300 Washington, D.C.
20006-3706 John Lee Science Applications International Corp.
5150 El Camino Real, Suite C-31 Los Altos, CA 94022 Bob Kassawara Electric Power Research Institute 3412 Hillview Ave P.O.
Box 10412 Palo Alto, CA 94303 1
i
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j Attachm:nt 1 j
Pcg31 of 7
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ULNRC-3229 RESPONSE TO THE FOLLOW-UP TO THE REQUEST FOR ADDITIONAL INFORMATION REGARDING GENERIC LETTER 92-08 i
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1.
Thermo-Lag Materials In Reference 1, Action item 1.a requested Union Electric to describe the specific tests and analyses performed to verify that the Thermo-Lag fire barrier materials that are currently installed at Callaway, or that will be installed in the future, are representative of the materials used to address the technicalissues associated with Thermo-Lag barriers and to construct the fire endurance and ampacity derating test specimens. The j
tests and analyses shall address the material properties and attributes determined or j
controlled by TSI during the manufacturing process and the quality assurance program.
The tests and analyses shall also address the material properties and attributes that contribute to conclusions that the Thermo-Lag materials and barriers conform to NRC regulations. These include:
l 1) chemical composition 2) material thickness 3) material weight and density i
4) the presence of voids, cracks, and delaminations 5) fire endurance capabilities 6) combustibility 7) flame spread rating 8) ampacity derating 9) mechanical properties such as tensile strength, compressive strength, shear strength, and flexural strength.
RESPONSE
With respect to item 1.a.1, Union Electric is cooperating with industry efforts to resolve the issues of Generic Letter 92-08. To this end, four samples of Thermo-Lag 330-1 were shipped to NUCON Intemational Inc., for pyrolysis gas chromatography (PGC) testing, to identify organic chemical constituents in accordance with the guidance of ASTM D3452. This is pursuant to the industry-wide testing program requested by NEl.
The shipment consisted of one sample each from the following:
A 3-hour preformed conduit section taken from an existing pl ant installation that was installed for regulatory compliance.
A 1-hour preformed conduit section taken from an existing plant installation that was installed for regulatory compliance.
A 3-hour rated panel taken from an existing plant installation that will be removed from the plant but was originally installed for regulatory compliance.
A 1-hour rated panel taken from an existing plant installation that was installed to satisfy separation requirements of IEEE 384.
On May 8,1995, Union Electric received a copy of the test results for Callaway from NUCON. The report concluded that " inspection of the pyrograms for these four Thermo-Lag samples indicates that they are consistent with other Thermo-Lag samples in terms of chemical composition." A copy of the test results has also been provided to
PCgo 2 of 7 ULNRC-3229 NEl for inclusion into a generic data pool which will be available to the industry and
-NRC.
While Callaway's samples were consistent with PGC test results previously performed by NUCON on 18 Thermo-Lag 330-1 samples taken from three utilities and from NEl stocks, the testing has identified one sample (out of approximately 100 samples tested to date) within the industry that did not meet the acceptance criteria for organic constituents. This anomalous material was installed during the 1983 time frame, whereas Callaway's material was installed during 1984. it is reasonable to conclude that the anomalous material came from another product batch. Based on the above, there is reasonable assurance that Callaway's material is consistent with the material tested by NEl, and provides Union Elecinc a basis to use generic test data with respect to fire endurance, flame spread, heat release, and combustibility. As such, we do not believe it is necessary to perform any additional chemical composition testing.
NEl will be contracting with NUCON labs for performance of additional chemical testing of selected samples to identify inorganic constituents. Eleven samples will be selected from the population of approximately 160 utility samples provided to NUCON for the industry chemical test program. The proposed approach involves energy dispersive spectroscopy of ashed Thermo-Lag samples in accordance with the general protocol of ASTM E-1508. NEl has stated that the chemical test program, including performance of testing for organics and inorganics, issuance of utility-specific test reports, and completion of a summary assessment, will be completed by July 31. NEl will forward the summary assessment to utilities and NRC by this date. If the summary assessment shows that the test results are consistent, no further action will be taken on this item.
With respect to item 1.a.2, Union Electric has joined the Electric Power Research Institute (EPRI) Tailored Collaboration (TC) effort as part of its resolution of Thermo-Lag issues. Science Applications Intemational Corporation (SAIC), the lead consultant for the EPRI.TC effort, has determined that there are three parameters which are important with respect to the qualification of the Thermo-Lag fire barriers. These are:
Raceway size e Baseline fire barrier thickness Band / wire spacing l
The data required to demonstrate baseline fire barrier thickness and band / wire spacing will be obtained as needed to support the TC analysis in accordance with the Thermo-l Lag resolution schedule contained in Attachment 5 to Reference 3. This timeline i
schedule currently shows completion of the Thermo-Lag resolution effort by the end of December 1996.
3..
With respect to items 1.a.3 and 1.a.4, two factors affect the importance of these items:
1.
The EPRI TC effort determin.stically quantifies the temperatures experienced by j-Thermo-Lag installed in the plant. ' Depending on the results of the calculations, some areas may have a significant margin of safety such that the Thermo-Lag will not ignite, irrespective of items 1.a.3 and 1.a.4, j_
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Attachm:mt 1 Page 3 of 7 ULNRC-3229 i
2.
As long as test results obtained through generic industry-wide testing are consistent, chemical composition testing alone should provide the necessary information with respect to product consistency.
While the TC calculations have not been completed, the results from the chemical testing program for Callaway's samples indicate that the material installed at Callaway is consistent with that which was tested by NEl during the Thermo-Lag fire endurance tests. As such, unless significant anomalies occur during the remainder of the organic i
and inorganic testing outlined above, we consider the material installed at Callaway to be acceptable from the standpoint of items 1.a.3 and 1.a.4.
With respect to items 1.a.5,1.a.6,1.a.7 and 1.a.8, Union Electric agrees with the NEl position. That is:
" we believe that performance of chemical composition testing alone will provide the necessary information with respect to product consistency, and will provide utilities a basis to use genenc test data with respect to fire endurance, flame spread, ignition threshold, heat release, and ampacity derating."
The results from the chemical testing program for Callaway's samples indicate that the material installed at Callaway is consistent with that which was tested by NEl during the Thermo ? ag fire endurance tests. As such, unless significant anomalies occur during the remainder of the organic and inorganic testing outlined above, we consider the material installed at Callaway to be acceptable from the standpoint of items 1.a.5, 1.a.6,1.a.7 and 1.a.8.
With respect to item 1.a.9, Union Electric agrees with the NEl position. That is:
'We would note that mechanical properties of the barner matenal would not be expected to be significant in tenns of seismic category 2 adequacy due to tie wires, banding, and other attachment methods. Further, shaker table testing of cable raceway barrierinstallations has recently been performed with acceptable results.. If (additional testing) is necessary, such testing should be performed generically, and utilities could use chemical testing to provide a basis for comparison to generic test data."
j The results from the chemical testing program for Callaway's samples indicate that the material installed at Callaway is consistent with that which was tested by NEl during the i
Thermo-Lag fire endurance tests. As such, unless significant anomalies occur during
{
the remainder of the organic and inorganic testing outlined above, we consider the material installed at Callaway to be acceptable from the standpoint of item 1.a.9.
i e
In Reference 1, Action item 1.b requested Union Electric to describe the methodology that will be used to determine the sample size and demonstrate that the sample size will be large enough to ensure that the information and data obtained will be sufficient to assess the total population of in-plant Thermo-Lag barriers and the matenals that will i
be installed in the future. In determining the sample size, consider the time of installation and manufacture of the various in-plant materials and barrier installations.
PCge 4 of 7-ULNRC-3229 Give the number and types (e.g., panels, conduit preshapes, trowel-grade material, stress skin) of samples that will be tested or analyzed.
- RESPONSE:
As noted above, Union Electnc believes that the sample size provided by the generic industry test program is sufficant to assure product consistency, especially since the test results are consistent with the exception of the one anomaly. Preliminary results from the TC program indicate that fire areas inside the Callaway Plant have levels of safety far beyond those needed to assure piei.ction of safe shutdown functions.. As such, in many fire areas a reduction in fire barrier rating, as determined during recent industry testing, may have no impact on the defense in depth objectives of Appendix R and the Callaway fire protection program.
~
With respect to the one anomaly, testing of the sample identified the presence of the essential organic constituents, with only the proportons being different from the other samples tested. ' NEl is taking further schons to establish whether the anomalous compossbon would affect fire barrier funcbon, and will report on this as information becomes available.
In Reference 1, Action item 1.c requested that Union Electric submit the schedule for verifying the Thermo-Lag materials.
RESPONSE
Union Electric is involved in the industry effort to evaluate chemical composition as a means of addressing product consistency. As noted, NEl will provide to the NRC and L
the industry, information on product consistency based on the chemical composition j
testing. This will be completed by July 31,1995. The results from the chemical testing i
i program for Callaway's samples indicate that the material installed at Callaway is
}
l consistent with that which was tested by NEl during the Thermo-Lag fire endurance l
tests. As such, unless significant anomalies occur during the remainder of the organic l
and inorganic testing outlined above, we consider the material installed at Callaway to i
be acceptable from the standpoint of items 1.a.1 through 1.a.9. If NRC agrees with the i
NEl position that the industry data can be used as a basis for using generic test data with respect to items 1.a.1 through 1.a.9, the schedule outlined in Reference 3 remains j
valid.
l in Reference 1, Action item 1.d requested Union Electric to submit, after the analyses and tests have been comp'eted, a written supplemental report confirming that the work I
has been completed, and to provide the results of the tests and analyses. Any changes to previously submitted plans or schedules resulting from the tests or analyses should also be described.
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l a-a
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Prge 5 of 7 F
ULNRC-3229
RESPONSE
P if additional analyses and testing are required, or if the issues outlined above are not resolved by industry testing, Union Electric will submit a supplemental report as requested in Action item 1.d.
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F 2.
Important Barrier Parameters in Reference 1, Action item 2.a requested that Union Electric describe the examinations and inspechons that will be performed to obtain the important barrier parameters given in Section ll of the RAI of December 1993 for the Thermo-Lag fire l.
barrier configurations installed at Callaway.
r i
RESPONSE
i As noted previously, SAIC has determined that there are three parameters which are important with respect to the qualification of the Thermo-Lag fire barriers. These are:
Raceway size e
Baseline fire banier thickness j
e l
Band / wire spacing Data required to confirm baseline fire barrier thickness and band / wire spacing will be j
obtained to support the TC analysis. The information/ parameters listed below will be documented as needed on a barrier-by-barrier basis as part of the Thermo-Lag
[
evaluation process:
i A.
Support protection, thermal shorts (penetrating elements).
t B.
Preformed conduit panels.
C.
Butt joints, or grooved and scored joints.
D.
Steel bands or tie wires.
l E.
Band / wire distance to joints.
i F.
No additional trowel material over sections and joints or additional trowel material
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applied.
i G.
Interfaces between Thermo-Lag materials and other fire barrier materials or L
building features.
i' H.
Intemal supports.
1-i e
. With respect to the chemical properties of Thermo-Lag materials, Union Electric agrees with the position provided to NRC in NEl's letter dated February 21,1995. That is:
"(By using the NEI chemical test program on an industry-wide basis), a generic i
. data pool can be created that willprovide extensin coverage of existing lot numbers without signi6 cant burdens foreach utility. Using this data pool, NEI l
7 l
sillprovide generic intbrmation on product consistency to industry and NRC.
(NEI's) int 6nt is to demonstrate reasonable assurance of product consistency.
[
We do not intend, nor do we believe it is practical or necessary, to establish a quantitative statistical basis or con &dence level with respect to product consistency. A quantitatively-based approach would require lot number p
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Att: chm:nt 1 P g: 6 of 7 ULNRC-3229 traceability, which cannot be established forthe vast majonty ofinstalled Thermo-Lag matenal."
With respect to the parameters of importance conceming cables protected by fire barriers, Callaway has obtained and verified the eight items listed in Action item II.A as listed below. It should be noted that no materials are present between the cables and the unexposed side of the fire barrier (for example, Sealtemp cloth).
1.
Cable size and type (power, control, or instrumentation).
2.
Cable jacket type (thermoplastic, thermoset) and materials.
3.
Cable conductor insulation type (thermoplastic, thermoset plastic) and materials.
4.
Cable fill and distribution of cab les within the protected conduit or cable tray.
5.
Proximity of cables to the unexposed (inside) surfaces of the fire barrier.
6.
Presence of materials between tne cables and the unexposed side of the fire barrier material (for example, Sealtemp cloth, which is used in the NEl test specimens).
7.
Cable operating temperature.
8.
Temperatures at which the cables can no longer perform their intended function when energized at rated voltage and current.
Detailed information will be retained on site for NRC audit of the above parameters.
In Reference 1, Action item 2.b requested Union Electric to describe the methodology applied to determine the number and type of representative in-plant fire barrier configurations that will be examined in detail, and demonstrate that the sample size is adequate to ensure that the information and data obtained are adequate to assess the total population of in-plant Thermo-Lag barriers. A large enough sample of the total population of configurations should be examined to provide reasonable assurance that the materials and important banier parameters used to construct the in-plant barriers and any future barrier installations or modifications, are representative of the parameters used to construct the fire endurance test specimens.
RESPONSE
Callaway has performed a general walk down of installed Thermo-Lag barriers. The parameters listed in item II.A of Reference 1 have been obtained and verified generically for the total population with the exception of those items listed above in items A through H. The parameters listed in Items A through H will be inspected as needed on a barrier-by-barrier basis as part of the Thermo-Lag evaluation process.
The results of these inspections will be compared to the NUMARC test configurations.
One of the following five actions will be selected to assure Thermo-Lag barrier acceptability:
- 1. Perform additional calculations, testing, or analyses to justify the barrier as-installed;
- 2. Upgrade the barrier to new test / installation criteria;
- 3. Replace the barrier with another approved fire barrier material;
- 4. Eliminate the need for the barrier by re-routing electrical circuits; or
Att chment 1 Pig 3 7 of 7 ULNRCr3229
~ ' 5. Evaluate the need for the barrier in view of safe shutdown attematives.
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. In Reference 1, Action item 2.c requested that Union Electric submit the schedule for obtaining all of the important barrier parameters.
- RESPONSE:
The important bamer parameters identified in 2.a above are being verified in f
accordance with the schedule outlined in Refemnce 3. However, some additional issues may arise as a result of the industry effort to evaluate chemical composition as a means of addressing product consistency, or as the TC effort is completed. Unless f
significant anomalies occur during the remainder of the organic and inorganic testing l
outlined above, or new issues arise as part of the TC effort, we will continue to verify the parameters described in our response to item 2.a in accordance with the schedule outlined in Reference 3.
i In Reference 1, Action item 2.d requested Union Electric to submit, after the information i
has been obtained and verified, a written supplemental report confirming that the work j
has been completed, and to provide the results of the examinaitions and inspections.
-l The report should verify that parameters of the in-plant configurations are i
representative of the parameters of the fire endurance test specimens and describe any changes to previously submitted plans or schedules that result from the examinations.
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RESPONSE
t
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If additional examinations and inspections beyond those already delineated in i
Reference 3 are required, or if the issues outlined above are not resolved by industry j
testing, Union Electric will submit a supplemental report as requested in Action item 2.d.
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b bi