(:¾ p; 0p.o. box 128, ft. pierce, fl 34954-0128 * february 11, 1994 l-94-33 10 cfr 50. 54 (f) mr....

P.O. Box 128, Ft. Pierce, FL 34954-0128

* February 11, 1994 L-94-33

10 CFR 50. 54 (f)Mr. Leonard J. CallanActing Associate Director for ProjectsU. S. Nuclear Regulatory CommissionAttn: Document Control DeskWashington, D. C. 20555

RE: St. Lucie Units 1 and 2Docket No. 50-335 and 50-389Request for Additional InformationGeneric Letter 92-08 Response

Dear Mr. Callan:

The additional information you requested from Florida Power and Light Company (FPL) on theSt. Lucie responses to Generic Letter (GL) 92-08, "Thermo-Lag 330-1 Fire Barriers," isattached. The original St. Lucie response was submitted by FPL letter, L-93-96, on April 16,1993.

Your letter to J. H. Goldberg, dated December 20, 1993, requested additional information onthe configurations and amounts of Thermo-Lag fire barriers installed at St. Lucie Plant and thecable loadings within particular Thermo-Lag configurations. In addition, your letter requestedplans and schedules for resolving the technical issues identified in GL 92-08 for thoseconfigurations that are outside the scope of NUMARC's test program or for those configurationsthat FPL deems impractical to upgrade. The information was requested to be provided within45 days of December 28, 1993, the date FPL received the NRC request. This letter alsoprovides the schedules requested by NRC letter (J. A. Norris to J. H. Goldberg) datedNovember 5, 1993.

The attached information is provided pursuant to the requirements of Section 182a of the AtomicEnergy Act of 1954, as amended, and 10.CFR 50.54(f).

Please contact us if there are any questions about this submittal.

Very truly yours,

D.A. $erVice P dentSt. Lucie Plant [ (:¾ p"; . 0

DAS/GRM/kw

DAS/PSL #1062-94

cc: Stewart D. Ebneter, Regional Administrator, Region II, USNRCSenior Resident Inspector, USNRC, St. Lucie Plant

9402180281 940211 .Jat, FPL tirowq canipmn, PDR ADOCK 05000335

St. Lucie Units 1 and 2Docket No. 50-335 and 50-389Request for Additional InformationGeneric Letter 92-08 Response

STATE OF FLORIDA )) ss.

COUNTY OF ST. LUCIE )

D. A. Sager being first duly sworn, deposes and says:

That he is Vice President, St. Lucie Plant for the Nuclear Division of Florida Power & LightCompany, the Licensee herein;

That he has executed the foregoing document; that the statements made in this document are trueand correct to the best of his knowledge, information and belief, and that he is authorized toexecute the document on behalf of said Licensee.

D. A. Saker

STATE OF FLORIDA

COUNTY OF HT. LUC 1 C

The foregoing instrument was acknowledged before

me this 11 day of _________ 19 _1_

by D. A. Sager, who is personally kkbwn to meand who did take an oath.

~AKAREN WE!;TGtq?- rI WE'ST I~ie -' VfRN ''s

Name of Notary Public cc v cc I C

My Commission expires 1f - l (7

Commission No. (C OC) 3 a a

St. Lucia Unit 1 Attachment IDocket 50-335Request for Additional InformationGeneric Letter 92-08 Page 1 of 10

ATTACHMENT 1

St. LUCIE UNIT 1 RESPONSE

APPROACH FOR RESOLUTION

In an effort to resolve the issues raised by NRC Bulletin 92-01 and Generic Letter (GL) 92-08,FPL has developed a performance-based approach to evaluate all Thermo-Lag fire barriers.This approach integrates the results of the NUMARC testing program for areas such as conduitsand pull boxes, provides for additional testing for configurations such as Thermo-Lag walls, andprovides for detailed engineering analys uate arameters (i.e., known and unknown) foreach Thermo-Lag installation. Thi erformance-basedapproach will use the combined resultsof area-by-area fire modeling, postulated ire anal industry-wide NUMARC and/orother relevant fire barrier testing 'probabilistic safety assessmentnd plant modifications, wherenecessary, to demonstrate the continuc abiity o s nuclear facilities to meet objectives of10 CFR 50, Appendix R. Listed below is an approximate time sequence of activities involvedwith resolution of Thermo-Lag issues:

- Developed a strategic plan for resolution of the Thermo-Lag issues including an outlineof the performance-based approach.

- Performed ampacity derating evaluations for all required Thermo-Lag protected circuits.Evaluations will be reviewed for continued acceptability when the additional NUMARCampacity derating testing is complete.

- Performed'design basis combustible loading evaluations for affected fire zones.

- Developing a performance-based fire model..'' ?

- Performing a review of records in an effort to obtain information that will help to verifyhow Thermo-Lag was installed and inspected. If useful, records such as plantmodification process sheets and quality control inspection reports will be used forverification and fire hazard analysis purposes.

- Setting up evaluations for determining fire barrier ratings which will utilize whenavailable the NUMARC application guide, NUMARC phase II testing and the specificplant installation configuration.

- Performing fire hazard analyses including both fire modelling and traditional NFPA firehazard methods using barrier ratings, design basis combustible loadings and useful plantmodification records.

- Applying probabilistic safety assessment (PSA) techniques to the fire model developedfor the IPEEE's, as a supplement to the deterministic efforts described above.

St. Lucie Unit 1 Attachment 1Docket 50-335Requesi for Additional InformationGeneric Letter 92-08 Page 2 of 10

- Submit a request for approval for FPL's performance-based approach to resolving theThermo-Lag issue.

- Maintain calculations on record for review by the NRC for those installations that do notachieve the 1-hour fire rating (or 3-hour as the case may be) but meet the requirementsof the performance-based fire hazards analyses.

- Evaluate modifications to the plant for those installations that do not achieve the 1-hourfire rating (or 3-hour as the case may be) and do not meet the acceptance criteria of theperformance-based fire hazard analyses.

FPL continues to work closely with NUMARC in developing the Thermo-Lag program. Basedon our assessment of the current and anticipated NUMARC initiatives in combination with theperformance-based approach FPL has developed, this combined approach provides a soundtechnical basis for resolving the issues associated with NRC Bulletin 92-01 and Generic Letter92-08 in a timely and cost effective manner. Our response to the NRC's Request for AdditionalInformation should be viewed in consideration of this approach.

NRC REOUEST (I.B.1.l

Describe the Thermo-Lag 330-1 barriers installed in the plant to

a. meet 10 CFR 50.48 or Appendix R to 10 CFR Part 50,b. support an exemption from Appendix R,c. achieve physical independence of electrical systems,d. meet a condition of the plant operating license,e. satisfy licensing commitments.

The descriptions should include the following information: the intended purpose and fire ratingof the barrier (for example, 3-hour fire barrier, 1-hour fire barrier, radiant energy heat shield),and the type and dimension of the barrier (for example, 8-ft by 10-ft wall, 4-ft by 3-ft by 2-ftequipment enclosure, 36-inch-wide cable tray, or 3-inch-diameter conduit).

FPL Response (I.B. 1 .!

St. Lucie Unit 1 was licensed to operate prior to January 1, 1979, and therefore, is required tomeet 10 CFR 50.48 and 10 CFR 50, Appendix R, Sections llI.G, J and 0. In general, Thermo-Lag 330-1 material is used for raceway fire proofing to meet the separation requirements of 10CFR 50, Appendix R, Section EI.G. Thermo-Lag 330-1 material is used for conduits, pull andjunction boxes, and for certain walls, floors, ceilings and radiant heat shields. Thermo-Lag 330-1 material is not applied to cable trays.

Conduits are protected with 3-hour rated Thermo-Lag fire barriers to meet the Appendix R,III.G.2 requirements. Conduits of diameters 1.5", 2", 3" and 4" are protected by preformedThermo-Lag conduit wrap.

St. Lucie Unit 1Docket 50-335

. Request for Additional InformationGeneric Letter 92-08

Attachment 1

Page 3 of 10

Pull and junction box barriers, constructed of Thermo-Lag, are used to meet Appendix R,Ill.G.2 requirements. 3-hour rated Thermo-Lag 330-1 panel material is used to protect fourelectrical boxes of dimensions 12" x 12" x 10", 18" x 18" x 12" and 24" x 36" x 12".

Thermo-Lag 330-1 panel material also is used to protect certain walls, floors and ceilings inrooms of the reactor auxiliary building. These rooms, consisting of stairwells, cable loft,inverter, and electrical equipment rooms, range in size from 100 ft2 to 531 ft2. In addition,Thermo-Lag panels are used as a radiant heat shield inside containment. All panel materialused is approximately 1" Thermo-Lag 330-1 material.

NRC REOUEST (T.B.2,)

For the total population of Thermo-Lag fire barriers described under Item I.B.1, submit anapproximation of:

a. For cable tray barriers: the total linear feet and square feet of 1-hour barriers and thetotal linear feet and square feet of 3-hour barriers.

b. For conduit barriers: the total linear feet of 1-hour barriers and the total linear feet of3-hour barriers.

c. For all other fire barriers: the total square feet of 1-hour barriers and the total square feetof 3-hour barriers.

d. For all other barriers and radiant energy heat shields: the total linear or square feet of1-hour barriers and the total linear or square feet of 3-hour barriers, as appropriate forthe barrier configuration or type.

FPL Response (I.B.2.)

Tabulated below are approximate amountsI.B.1:

of Thermo-Lag fire barriers described under Item

Barrier Type I 1-hr LF I 1-hr SF I 3-hr LF I 3-hrSF

Trays None None None None

Conduits None NA 1361 NA

Boxes NA None NA 73

Walls, Floors, NA None NA 3992Ceilings I

Radiant Heat Shields NA None NA 267

St. Lucie Unit 1 Attachment 1Docket 50-335Request for Additional InformationGeneric Letter 92-08 Page 4 of 10

NRC REQUEST (mI1.!l

State whether or not you have obtained and verified each of the aforementioned parameters foreach Thermo-Lag barrier installed in the plant. If not, discuss the parameters you have notobtained or verified. Retain detailed information on site for NRC audit where theaforementioned parameters are known.

FPL Response (II.B. l.)

At this time we do not have sufficient information to determine to what extent critical barrierparameters have been verified for each Thermo-Lag barrier installed in the plant. We will begina verification effort coincident with the release of the NUMARC application guide. Theapplication guide will contain a listing of the critical design and installation parameters and willbe provided to us when the NUMARC Phase II testing is complete. It is expected that the finallist of critical parameters will vary somewhat from the present list when Phase II testing resultsare completed. FPL is reluctant to engage in activities at this time that may prove to beredundant after the phase II testing is complete and the application guide is available.

However, FPL is performing a review of records in an effort to obtain information that may helpto verify how Thermo-Lag was installed and inspected. If useful, information from installationrecords such as plant modification process sheets and quality control inspection reports will beused to perform verification of critical barrier parameters.

FPL does not intend to exceed the tested time rating (as determined by NUMARC testing) foundfor each barrier using the 325 IF raceway temperature acceptance criteria. It is not FPL'sintention to rely on further cable functionality testing to justify particular cable configurations.To the extent that fire test results are satisfactory on the basis of temperature, as provided in theNRC draft test and acceptance criteria, we do not believe the listed cable performanceparameters need be considered further.

FPL is working closely with NUMARC in developing the Thermo-Lag program. Based on ourassessment of the current and anticipated NUMARC initiatives we are expecting that the resultsof the NUMARC Thermo-Lag program and testing will be sufficient to resolve the Thermo-Lagfire barrier issues identified in Generic Letter 92-08 for St. Lucie Plant.

NRC REQUEST Ml.B.2.)

For any parameter that is not known or has not been verified, describe how you will evaluatethe in-plant barrier for acceptability.

FPL Response (IT.B.2.)

At this time we do not have sufficient information to describe how we will evaluate the in-plantbarriers for acceptability. Upon receipt of the NUMARC application guide, we will apply


developed techniques such as worst case test results to evaluate the fire rating of in-plant barrierswhere barrier parameters have not been verified.

NRC REQUEST m.B3.'

To evaluate NUMARC's application guidance an understanding of the types and extent of theunknown parameters is needed. Describe the type and extent of the unknown parameters at yourplant in this context.

FPL Response (IT.B.3.)

At this time we do not have sufficient information to describe the type and extent of unknownv, parameters at St. Lucie Plant. We will begin an effort to determine the type and extent of

F unknown parameters coincident with the release of the NUMARC application guide. Thepayf7 application guide will contain a listing of the critical design and installation parameters and will

be provided to us when the NUMARC Phase II testing is complete. It is expected that the finallist of critical parameters will vary somewhat from the present list when Phase II testing iscompleted. FPL does not want to begin activities that may prove to be redundant after theNUMARC application guide is issued. However, FPL is performing a review of records in aneffort to obtain information that may help to verify how Thermo-Lag was installed andinspected. If useful, information from installation records such as plant modification processsheets and quality control inspection reports will be used to perform verification of criticalbarrier parameters.

NRC REQUEST (TTI B. 1.'

Describe the barriers discussed under Item I.B. 1 that you have determined will not be boundedby the NUMARC test program.

FPL Response (III.B. I.)

Thermo-Lag 330-1 material is used as walls, floors, ceilings and radiant heat shields in certainapplications to provide fire protection. These configurations are currently not included in theNUMARC testing. Estimates of the amount of Thermo-Lag in these configurations are tabulatedin I.B.2.

NRC REOUEST (aI.B.2.)

Describe the plant-specific corrective action program or plan you expect to use to evaluate thefire barrier configurations particular to the plant. This description should include a discussionof the evaluations and the tests being considered to resolve the fire barrier issues identified inGL 92-08 and to demonstrate the adequacy of existing in-plant barriers.


FPL Response MI.B.2.a

FPL plans to sponsor NUMARC testing of Thermo-Lag 330-1 for our configurations discussedin fII.B.1. The scope of the testing is currently being developed. The results of testing areplanned to be factored into FPL's approach to resolving Thermo-Lag fire barrier issuesa a p r - and-provides a souni issuesPraised by NRC Bulletin 92-01 and Generic Letter 92-08. Further discussion of this approach

NRC REOUEST (MTI.B.3.)

If a plant-specific fire endurance test program is anticipated, describe the following:

a. Anticipated test specimens.

b. Test methodology and acceptance criteria including cable functionality.

FPL Response (TI.B.3.)

See Response m.B.2.

NRC REOUEST (TV.B.1)

For the barriers described under Item I.B. 1, describe those that you have determined will fallwithin the scope of the NUMARC program for ampacity derating, those that will not be boundedby the NUMARC program, and those for which ampacity derating does not apply.

FPL Response (IV.B1.).

St. Lucie raceways containing power cables protected by Thermo-Lag barriers fall within thescope of the NUMARC program for ampacitf derating. Conduits requiring protection withThermo-Lag 330-1 have been evaluated. After applying a 15% derating factor (based onTSI/ITL ampacity derating tests, as discussed in our April 16, 1993 response to GL 92-08) forall Thermo-Lag enclosed conduits, the remaining worst case ampacity derating margin is 29%.This provides a substantial margin over the circuit's ampacity requirements.

Further ampacity derating tests are planned as part of the NUMARC Thermo-Lag program.When the NUMARC sponsored testing is completed and accepted by the NRC, we will ensurethat results relative to each application of Thermo-Lag are acceptable. However, we areconfident that the results will continue to demonstrate substantial margin over requirements.


NRC REQUEST (IV.B.2'

For the barriers you have determined fall within the scope of the NUMARC program, describewhat additional testing or evaluation you will need to perform to derive valid ampacity deratingfactors.

FPL Response (IV.B.2.)

Due to the margin shown in ampacity derating calculations on Thermo-Lag protected circuits,we are not anticipating any additional FPL evaluation or testing beyond the NUMARC sponsoredtesting program.

NRC REQUEST CIV.B.3)

or the barrier configurations that you have determined will not be bounded by the NUMARCest program, describe your plan for evaluating whether or not the ampacity derating test relied

,,upon for the ampacity derating factors used for those electrical components protected by4 ~ Thermo-Lag 330-1 (for protecting the safe-shutdown capability from fire or to achieve physical

independence of electrical systems) are correct and applicable to the plant design. Describe allcorrective actions needed and submit the schedule for completing such actions.

FPL Response (IV.B.3.'

See response to IV.B. 1.

NRC REQUEST WV.B.4)

In the event that the NUMARC fire barrier tests indicate the need to upgrade existing in-plantbarriers or to replace existing Thermo-Lag barriers with another fire barrier system, describethe alternative actions you will take (and the schedule for performing those actions) to confirmthat the ampacity derating factors were derived by valid tests and are applicable to the modifiedplant design.

FPL Response aV.B.4.1

We do not plan to replace the present raceway fire barrier material with another type. Ampacityderating testing is scheduled to be performed by NUMARC using additional thicknesses ofThermo-Lag. Due to the low thermal resistance of Thermo-Lag in the non-fire application, asubstantially different ampacity derating is not anticipated. However, as identified in previouscorrespondence, ampacity margins at St. Lucie Unit 1, using design and construction criteria,are sufficiently large to encompass proposed ampacity derating well over that presently tested.

St. Lucie Unit 1 Attachment 1Docket 50-335Bequest for Additional InformationGeneric Letter 92-08 Page 8 of 10

NRC REOUEST (V.B.U

Describe the specific alternatives available to you for achieving compliance with NRC fireprotection requirements in plant areas that contain Thermo-Lag fire barriers. Examples ofpossible alternatives to Thermo-Lag based upgrades include the following:

1. Upgrade existing in-plant barriers using other materials.2. Replace Thermo-Lag barriers with other fire barrier materials or systems.3. Reroute cables or relocate other protected components.4. Qualify 3-hour barriers as 1-hour barriers and install detection and suppression systems

lA to satisfy NRC fire protection requirements.

FPL Response (V.B.)

As previously discussed in IU.B.2, FPL has developed a performanc ased.,ash that usesdetailed engineering analyses to evaluate whether St. Lucie P the objectives O10 CFR50, Appendix R. This approach uses area-by-area fire modeling, fire azards anayses, industry-

W - wide NUMARC and/or other relevant fire barrier testing, and probabilistic safety assessment(PSA). The output of the FPL approach,including any required modifications, will limit fire

(L [ damage to structures, systems and components important to safety so that the capability to safelyt 0 shutdown the plant is ensured. In this regard, the approach is consistent with Appendix R

objectives and is an alternative to the 1-hour and 3-hour rated fire barriers. A meeting betweenFPL and NRC staff is suggested to discuss this approach in further detail.

i 'tiWith respect to the Thermo-Lag 330-1 installations discussed in m.B. I., FPL plans to sponsorNUMARC testing of this type configuration. The scope of the testing is currently beingdeveloped. The results of testing are planned to be factored into FPL's performance-basedapproach to resolving Thermo-Lag fire barrier issues as discussed above.

NRC REOUTEST (VI.B.)

Submit an integrated schedule that addresses the overall corrective action schedule for the plant.At a minimum, the schedule should address the following aspects for the plant:

1. implementation and completion of corrective actions and fire barrier upgrades for firebarrier configurations within the scope of the NUMARC program,

2. implementation and completion of plant-specific analyses,m testing, or alternative actionsfor fire barrier outside the scope of the NUMARC program.

FPL Response (VI.B.)

FPL has been actively pursuing a resolution of the Thermo-Lag problem since the first quarterof 1993. Those activities that have been completed to date include the following:

St. Lucia Unit 1 Attachment 1Docket 50-335Request for Additional InformationGeneric Ltner 92-08 Page 9 of 10

1. FPL has been supporting NUMARC in the development of Thermo-Lag testing program.

2. As described previously, a strategic plan has been developed for the overall resolutionof Thermo-Lag concerns. Within the scope of this plan, a computer based fire modelis nearing completion.

3. We have completed ampacity derating evaluations for all required Thermo-Lag protectedcircuits. Evaluations will be reviewed for continued acceptability when the additionalNUMARC ampacity derating testing is complete.

4. We have completed design basis combustible loading evaluations for affected fire zones.

Because the NUMARC test results and Application Guide have not been received in a final format this time, it is premature to provide a complete integrated schedule for resolution at this time.However, it is possible to identify those activities that are presently scheduled and to identifywhen a more detailed schedule can be provided in light of the NUMARC test results:

1. FPL intends to submit its performance-based approach for resolution of the Thermo-Lagissue for NRC approval in the second quarter of 1994. It is FPL's intention to meet withthe NRC to discuss this approach.

2. NUMARC is scheduled to issue the results of its testing program on April 15, 1994.Following receipt of this information, FPL will review the information for applicabilityto St. Lucie Plant installations. Evaluations will be performed comparing the FPLinstallations to the NUMARC testing so that appropriate fire ratings for the FPLinstallations can be established. It is anticipated that these evaluations will be completedduring the third quarter of 1994 after receipt of the NUMARC test results.

3. At the present time, FPL is performing postulated fire hazards analyses'on an area byarea basis. Completion of the postulated fire hazards analyses is anticipated by the endof the third quarter of 1994.

4. A probabilistic safety assessment is being performed for fire areas to further evaluate theadequacy of installed fire barriers. This work is scheduled to be completed in the fourthquarter of 1994.

5. An engineering schedule will be developed for installations that do not meet theacceptance criteria for either the performance-based fire hazard analyses or theprobabilistic safety assessment. For areas that require upgrade, an engineering estimateand schedule will be developed. This engineering estimate will then be used to developa construction estimate. Accordingly, scheduling information regarding plantmodifications required, is expected to be provided to NRC by the end of January 1995.


NRC REOUEST (VYI.) Sources and Correctness of Information

Describe the sources of the information provided in response to this request for information (forexample, from plant drawing, quality assurance documentation, walkdown or inspections) andhow the accuracy and validity of the information was verified.

FPL Response (VNI.)

The majority of information contained in this request that describes the plant's configuration isfrom plant design documents and drawings. The remaining information about the plant wasobtained via plant walkdowns. All plant information was independently verified.

St. Lucie 2 Attachment 2Docket 50-389Request For Additional InformationGeneric Letter 92-08 Response Page 1 of 10

ATTACHMENT 2

St. LUCIE UNIT 2 RESPONSE

APPROACH FOR RESOLUTION

In an effort to resolve the issues raised by NRC Bulletin 92-01 and Generic Letter (GL) 92-08,FPL has developed a performance-based approach to evaluate all Thermo-Lag fire barriers.This approach integrates the results of the NUMARC testing program for areas such as conduitsand pull boxes, provides for additional testing for configurations such as Thermo-Lag walls, andprovides for detailed engineering analyses to evaluate parameters (i.e., known and unknown) foreach Thermo-Lag installation. This performance-based approach will use the combined resultsof area-by-area fire modeling, postulated fire hazards analysis, industry-wide NUMARC and/orother relevant fire barrier testing, probabilistic safety assessment, and plant modifications, wherenecessary, to demonstrate the continued ability of FPL's nuclear facilities to meet objectives of10 CFR 50, Appendix R. Listed below is an approximate time sequence of activities involvedwith resolution of Thermo-Lag issues:

- Developed a strategic plan for resolution of the Thermo-Lag issues including an outlineof the performance:-based approach.

- Performed ampacity derating evaluations for all required Thermo-Lag protected circuits.Evaluations will be reviewed for continued acceptability when the additional NUMARCampacity derating testing is complete.

- Performed design basis combustible loading evaluations for affected fire zones.

- Developing a performance-based fire model.

- Performing a review of records in an effort to obtain information that will help to verifyhow Thermo-Lag was installed and inspected. If useful, records such as plantmodification process sheets and quality control inspection reports will be used forverification and fire hazard analysis purposes.

- Setting up evaluations for determining fire barrier ratings which will utilize whenavailable the NUMARC application guide, NUMARC phase II testing and the specificplant installation configuration.

- Performing fire hazard analyses including both fire modelling and traditional NFPA firehazard methods using barrier ratings, design basis combustible loadings and useful plantmodification records.

- Applying probabilistic safety assessment (PSA) techniques to the fire model developedfor the IPEEE's, as a supplement to the deterministic efforts described above.


- Submit a request for approval for FPL's performance-based approach to resolving theThermo-Lag issue.

- Maintain calculations on record for review by the NRC for those installations that do notachieve the 1-hour fire rating (or 3-hour as the case may be) but meet the requirementsof the performance-based fire hazards analyses.

- Evaluate modifications to the plant for those installations that do not achieve the 1-hourfire rating (or 3-hour as the case may be) and do not meet the acceptance criteria of theperformance-based fire hazard analyses.

FPL continues to work closely with NUMARC in developing the Thermo-Lag program. Basedon our assessment of the current and anticipated NUMARC initiatives in combination with theperformance-based approach FPL has developed, this combined approach provides a soundtechnical basis for resolving the issues associated with NRC Bulletin 92-01 and Generic Letter92-08 in a timely and cost effective manner. Our response to the NRC's Request for AdditionalInformation should be viewed in consideration of this approach.

NRC REOUEST (!.B. l)

Describe the Thermo-Lag 330-1 barriers installed in the plant to

a. .nieet 10 CFR 50.48 or Appendix R to 10 CFR Part 50.b. support an exemption from Appendix R,c. achieve physical independence of electrical systems,d. meet a condition of the plant operating license,e. satisfy licensing commitments.

The descriptions should include the following information: the intended purpose and fire ratingof the barrier (for example, 3-hour fire barrier, 1-hour fire barrier, radiant energy heat shield),and the type and dimension of the barrier (for example, 8-ft by 10-ft wall, 4-ft by 3-ft by 2-ftequipment enclosure, 36-inch-wide cable tray, or 3-inch-diameter conduit).

FPL Response (I.B.l.u

For St. Lucie Unit 2, FPL is committed to meet the technical requirements of 10 CFR 50Appendix R and the intent of Regulatory Guide 1.75 as documented in the NRC SafetyEvaluation Report (NUREG-0843, dated October 1981 and its supplements). In general,Thermo-Lag 330-1 material is used to satisfy these commitments. Thermo-Lag 330-1 materialis used for conduits, pull and junction boxes, and for certain walls, floors, ceilings and radiantheat shields. Thermo-Lag 330-1 material is not applied to cable trays.

Conduits are protected with 1-hour and 3-hour rated Thermo-Lag fire barriers to meetcommitments for Appendix R and Regulatory Guide 1.75. Conduits of diameters 1", 1.5", 2",3", 4" and 5" are protected by preformed Thermo-Lag conduit wrap.

St. Lucia 2Docket 50-389Request For Additional InformationGeneric Letter 92-08 Response

Attachment 2

Page 3 of 10

Pull and junction box barriers, constructed of Thermo-Lag, are used to meet commitments forAppendix R. 3-hour rated Thermo-Lag 330-1 panel material is used to protect four electricalboxes of dimensions 18"x18"x6', 12"x48fx12w, 42"x42"x12" and 60"xl2"x12".

Thermo-Lag 330-1 panel material also is used to protect certain walls, floors and ceilings inrooms of the reactor auxiliary building. These rooms, consisting of stairwells, cable loft,inverter, and electrical equipment rooms, range in size from 100 ft2 to 531 ft2. In addition,Thermo-Lag panels are used as a radiant heat shield inside containment. All panel materialused is approximately 1" Thermo-Lag 330-1 material.

NRC REOUEST (I.B.2.)

For the total population of Thermo-Lag fire barriers described under Item I.B.1, submit anapproximation of:

a. For cable tray barriers: the total linear feet and square feet of 1-hour barriers and thetotal linear feet and square feet of 3-hour barriers.

b. For conduit barriers: the total linear feet of 1-hour barriers and the total linear feet of3-hour barriers.

c. For all other fire barriers: the total square feet of 1-hour barriers and the total square feetof 3-hour barriers.

d. For all other barriers and radiant energy heat shields: the total linear or square feet of1-hour barriers and the total linear or square feet of 3-hour barriers, as appropriate forthe barrier configuration or type.

FPL Response (I.B.2.)

Tabulated below are approximate amounts of Thermo-LagI.B.1:

fire barriers described under Item

Barrier Type' 1-hr LF 1-hr SF 3-hr LF 3-hr SF

Trays None None None None

Conduits 2421. NA 1311 NA

Boxes NA None NA 103

Walls, Floors, NA None NA 3295Ceilings

Radiant Heat Shields NA None NA 439

2 t 6

iO6

St. Lucie 2 Attachment 2Docket 50-389Request For Additional Information*Generic Letter 92-08 Response Page 4 of 10

NRC REQUEST (lI.B 1.)

State whether or not you have obtained and verified each of the aforementioned parameters foreach Thermo-Lag barrier installed in the plant. If not, discuss the parameters you have notobtained or verified. Retain detailed information on site for NRC audit where theaforementioned parameters are known.

FPL Response MT.B. 1!

At this time we do not have sufficient information to determine to what extent critical barrierparameters have been verified for each Thermo-Lag barrier installed in the plant. We will begina verification effort coincident with the release of the NUMARC application guide. Theapplication guide will contain a listing of the critical design and installation parameters and willbe provided to us when the NUMARC Phase II testing is complete. It is expected that the finallist of critical parameters will vary somewhat from the present list when Phase II testing resultsare completed. FPL is reluctant to engage in activities at this time that may prove to beredundant after the phase II testing is complete and the application guide is available. However,FPL is performing a review of records in an effort to obtain information that may help to verifyhow Thermo-Lag was installed and inspected. If useful, information from installation recordssuch as plant modification process sheets and quality control inspection reports will be used toperform verification of critical barrier parameters.

FPL does not intend to exceed the tested time rating (as determined by NUMARC testing) foundfor each barrier using the 325 'F raceway temperature acceptance criteria. It is not FPL'sintention to rely on further cable functionality testing to justify particular cable configurations.To the extent that fire test results are satisfactory on the basis of temperature, as provided in theNRC draft test and acceptance criteria, we do not believe the listed cable performanceparameters need be considered further.

FPL is working closely with NUMARC in developing the Thermo-Lag program. Based on ourassessment of the current and anticipated NUMARC initiatives we are expecting that the resultsof the NUMARC Thermo-Lag program and testing will be sufficient to resolve the Thermo-Lagfire barrier issues identified in Generic Letter 92-08 for St. Lucie Plant.

NRC REQUEST (al.B.2.)

For any parameter that is not known or has not been verified, describe how, you will evaluatethe in-plant barrier for acceptability.

FPL Response M.B.2.)

At this time we do not have sufficient information to describe how we will evaluate the in-plantbarriers for acceptability. Upon receipt of the NUMARC application guide, we will apply

St. Lucie 2 Attachment 2Docket 50-389Request For Additional Information'Generic Letter 92-08 Response Page 5 of 10

developed techniques such as worst case test results to evaluate the fire rating of in-plant barrierswhere barrier parameters have not been verified.

NRC REQUEST (TI.B.3.

To evaluate NUMARC's application guidance an understanding of the types and extent of theunknown parameters is needed. Describe the type and extent of the unknown parameters at yourplant in this context.

FPL Response (aI.B.3.)

At this time we do not have sufficient information to describe the type and extent of unknownparameters at St. Lucie Plant. We will begin an effort to determine the type and extent ofunknown parameters coincident with the release of the NUMARC application guide. Theapplication guide will contain a listing of the critical design and installation parameters and willbe provided to us when the NUMARC Phase II testing is complete. It is expected that the finallist of critical parameters will vary somewhat from the present list when Phase II testing iscompleted. FPL does not want to begin activities that may prove to be redundant after theNUMARC application guide is issued. However, FPL is performing a review of records in aneffort to obtain information that may help to verify how Thermo-Lag was installed andinspected. If useful, information from installation records such as plant modification processsheets and quality control inspection, reports will be used to perform verification of criticalbarrier parameters.

NRC REQUEST (IH.E.I.4

Describe the barriers discussed under Item I.B.l that you have determined will not be boundedby the NUMARC test program.

FPL Response (mlB.1.

Thermo-Lag 330-1 material is used as walls, floors, ceilings and radiant heat shields in certainapplications to provide fire protection. These configurations are currently not included in theNUMARC testing. Estimates of the amount of Thermo-Lag in these configurations are tabulatedin I.B.2.

NRC REOUEST (ITT.B.2.)

Describe the plant-specific corrective action program or plan you expect to use to evaluate thefire barrier configurations particular to the plant. This description should include a discussionof the evaluations and the tests being considered to resolve the fire barrier issues identified inGL 92-08 and to demonstrate the adequacy of existing in-plant barriers.


FPL Response (HI.B.2.)

FPL plans to sponsor NUMARC testing of Thermo-Lag 330-1 for our configurations discussedin III.B.1. The scope of the testing is currently being developed. The results of testing areplanned to be factored into FPL's approach to resolving Thermo-Lag fire barrier issues. Theapproach is performance-based and provides a sound technical basis for resolving the issuesraised by NRC Bulletin 92-01 and Generic Letter 92-08. Further discussion of this approachis provided in V.B.

NRC REOUEST (11.B.3A)

If a plant-specific fire endurance test program is anticipated, describe the following:

a. Anticipated test specimens.

b. Test methodology and acceptance criteria including cable functionality.

FPL Response (TII.B.3.)

See Response M.B.2.

NRC REOUEST (aV.B. 1)

For the barriers described under Item I.B. 1, describe those that you have determined will fallwithin the scope of the NUMARC program for ampacity derating, those that will not be boundedby the NUMARC program, and those for which ampacity derating does not apply.

FPL Response (IV.B.l) I

St. Lucie raceways containing power cables protected by Thermo-Lag barriers fall within thescope of the NUMARC program for ampacity derating. Conduits requiring protection withThermo-Lag 330-1 have been evaluated. After applying a 15% derating factor (based onTSI/ITL ampacity derating tests, as discussed in our April 16, 1993 response to GL 92-08) forall Thermo-Lag enclosed conduits, the remaining worst case ampacity derating margin is 43 %.This provides a substantial margin over the circuit's ampacity requirements.

Further amnpacity derating tests are planned as part of the NUMARC Thermo-Lag program.When the NUMARC sponsored testing is completed and accepted by the NRC, we will ensurethat the results relative to each application of Thermo-Lag are acceptable. However, we areconfident that the results will continue to demonstrate substantial margin over requirements.


NRC REOUEST aV.B.21

For the barriers you have determined fall within the scope of the NUMARC program, describewhat additional testing or evaluation you will need to perform to derive valid ampacity deratingfactors.

FPL Response (IV.B.2.,

Due to the margin shown in ampacity derating calculations on Thermo-Lag protected circuits,we are not anticipating any additional FPL evaluation or testing beyond the NUMARC sponsoredtesting program.

NRC REOUEST (IVB.B3'

For the barrier configurations that you have determined will not be bounded by the NUMARCtest program, describe your plan for evaluating whether or not the ampacity derating test reliedupon for the ampacity derating factors used for those electrical components protected byThermo-Lag 330-1 (for protecting the safe-shutdown capability from fire or to achieve physicalindependence of electrical systems) are correct and applicable to the plant design. Describe allcorrective actions needed and submit the schedule for completing such actions.

FPL Response (TV.B,3)

See Response IV.B.I.

NRC REOUEST (IV.B.4)

In the event that the NUMARC fire barrier tests indicate the need to upgrade existing in-plantbarriers or to replace existing Thermo-Lag barriers with another fire barrier system, describethe alternative actions you will take (and the schedule for performing those actions) to confirmthat the ampacity derating factors were derived by valid tests and are applicable to the modifiedplant design.

FPL Response TV.B.4.)

We do not plan to replace the present raceway fire barrier material with another type. Ampacityderating testing is scheduled to be performed by NUMARC using additional thicknesses ofThermo-Lag. Due to the low thermal resistance of Thermo-Lag in the non-fire application, asubstantially different ampacity derating is not anticipated. However, as identified in previouscorrespondence, ampacity margins at St. Lucie Unit 2, using design and construction criteria,are sufficiently large to encompass proposed ampacity derating well over that presently tested.

St. Lucie 2 Attachment 2Docket 50-389Request For Additional Information'Generic Letter 92-08 Response Page 8 of 10

NRC REQUEST (V.B.,

Describe the specific alternatives available to you for achieving compliance with NRC fireprotection requirements in plant areas that contain Thermo-Lag fire barriers. Examples ofpossible alternatives to Thermo-Lag based upgrades include the following:

1. Upgrade existing in-plant barriers using other materials.2. Replace Thermo-Lag barriers with other fire barrier materials or systems.3. Reroute cables or relocate other protected components.4. Qualify 3-hour barriers as 1-hour barriers and install detection and suppression systems

to satisfy NRC fire protection requirements.

FPL Response (V.B.)

As previously discussed in III.B.2, FPL has developed a performance-based approach that usesdetailed engineering analyses to evaluate whether St. Lucie Plant meets the objectives of 10 CFR50, Appendix R. This approach uses area-by-area fire modeling, fire hazards analyses, industry-wide NUMARC and/or other relevant fire barrier testing, and probabilistic safety assessment(PSA). The output of the FPL approach, including any required modifications, will limit firedamage to structures, systems and components important to safety so that the capability to safelyshutdown the plant is ensured. In this regard, the approach is consistent with Appendix Robjectives and is an alternative to the 1-hour and 3-hour rated fire barriers. A meeting betweenFPL and NRC staff is suggested to discuss this approach in further detail.

With respect to the Thermo-Lag 330-1 installations discussed in fII.B. 1., FPL plans to sponsorNUMARC testing of this type configuration. The scope of the testing is currently beingdeveloped. The results of testing are planned to be factored into FPL's performance-basedapproach to resolving Thermo-Lag fire barrier issues as discussed above.

NRC REOUEST (VI.U

Submit an integrated schedule that addresses the overall corrective action schedule for the plant.At a minimum, the schedule should address the following aspects for the plant:

1. implementation and completion of corrective actions and fire barrier upgrades for firebarrier configurations within the scope of the NUMARC program,

2. implementation and completion of plant-specific analyses,m testing, or alternative actionsfor fire barrier outside the scope of the NUMARC program.

FPL Response (VI.B.)

FPL has been actively pursuing a resolution of the Thermo-Lag problem since the first quarterof 1993. Those activities that have been completed to date include the following:

St. Lucie 2 Attachment 2Docket 50,389Rdquest For Additional Informationbeneric Letter 92-08 Response Page 9 of 10

1. FPL has been supporting NUMARC in the development of Thermo-Lag testing program.

2. As described previously, a strategic plan has been developed for the overall resolutionof Thermo-Lag concerns. Within the scope of this plan, a computer based fire modelis nearing completion.

3. We have completed ampacity derating evaluations for all required Thermo-Lag protectedcircuits. Evaluations will be reviewed for continued acceptability when the additionalNUMARC ampacity derating testing is complete.

4. We have completed design basis combustible loading evaluations for affected fire zones.

Because the NUMARC test results and Application Guide have not been received in a final format this time, it is premature t6 provide a complete integrated schedule for resolution at this time.However, it is possible to identify those activities that are presently scheduled and to identifywhen a more detailed schedule can be provided in light of the NUMARC test results:

1. FPL intends to submit its performance-based approach for resolution of the Thermo-Lagissue for NRC approval in the second quarter of 1994. It is FPL's intention to meet withthe NRC to discuss this approach.

2. NUMARC is scheduled to issue the results of its testing program on April 15, 1994.Following receipt of this information, FPL will review the information for applicabilityto St. Lucie Plant installations. Evaluations will be performed comparing the FPLinstallations to the NUMARC testing so that appropriate fire ratings for the FPLinstallations can be established. It is anticipated that these evaluations will be completedduring the third quarter of 1994 after receipt of the NUMARC test results.

3. At the present time, FPL is performing postulated fire hazards analyses on an area byarea basis. Completion of the postulated fire hazards analyses is anticipated by the endof the third quarter of 1994.

4. A probabilistic safety assessment is being performed for fire areas to further evaluate theadequacy of installed fire barriers. This work is scheduled to be completed in the fourthquarter of 1994.

5. An engineering schedule will be developed for installations that do not meet theacceptance criteria for either the performance-based fire hazard analyses or theprobabilistic safety assessment. For areas that require upgrade, an engineering estimateand schedule will be developed. This engineering estimate will then be used to developa construction estimate. Accordingly, scheduling information regarding plantmodifications required, is expected to be provided to NRC by the end of January 1995.

St. Lucie 2 Attachment 2Docket 50-389Request For Additional Information'Generic Letter 92.08 Response Page 10 of 10

NRC REOUEST (VMI.) Sources and Correctness of Information

Describe the sources of the information provided in response to this request for information (forexample, from plant drawing, quality assurance documentation, walkdown or inspections) andhow the accuracy and validity of the information was verified.

FPL Response (VII.)

The majority of information contained in this request that describes the plant's configuration isfrom plant design documents and drawings. The remaining information about the plant wasobtained via plant walkdowns. All plant information was independently verified.

(:¾ p; 0p.o. box 128, ft. pierce, fl 34954-0128 * february 11, 1994 l-94-33 10 cfr 50. 54 (f) mr....

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