ML18033A739
| ML18033A739 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 03/11/1976 |
| From: | Moeller D Advisory Committee on Reactor Safeguards |
| To: | Anders W NRC COMMISSION (OCM) |
| Shared Package | |
| ML18033A737 | List: |
| References | |
| NUDOCS 8905170008 | |
| Download: ML18033A739 (30) | |
Text
APPENDIX B ADVISORY COMMITTEE ON REACTOR SAFEGUARDS NUCI EAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 March 11, 1976 Honorable William A. Anders Chairman U. S. Nuclear Regulatory Coanission Washington, DC 20555
Subject:
REPORT CH PRDK&X REPlORATICH AND OPERATIQVZ TEST32K OF BRANS PERI% NIX:LEAR PZiQKg UNITS 1 ÃK) 2
Dear Hr. Anders:
At its 191st meeting, Yarch 4-6, 1976> the Advisory Committee on Reactor Safeguards met with the Tennessee Valley Authority (TVA) to review repairs and modifications to be made to the BroIns Ferry Nuclear Plant, Units 1 and 2 prior to restart of these units following the fire on Yarch 22, 1975.
These matters were previously considered at a SubcaImittee meeting on February 27, 1976, in Kashington, DC.
During its review, the Conmittee had the benefit of discussions with representatives arxi consultants of the Mnnesse Valley Authority and.the
Ãuc e adulatory COIrxnission
(?GC)
Stafr".
The Comnittee also nad the benefit of the documents listed.
The Browns Ferry Nuclear Plant consists of three boiling water reactors.
At the tim of the fire Units 1 and 2 were operating and Wit 3 was still under construction.
Following the fire the fuel was reraved from Units 1 and 2 and since has remained stored in the fuel storage pools.
The Tech-nical Specificaticns mre changed to provide for protective measures for the fuel while in the storage pools.
TVA has conducted an extensive program to determine dunnage from the fire.
It was conclude that the major damage occurred in the reactor building, outside the cable spreading roan wnere the fire started.
There has been no evidence of significant structural damage and only minor damage to piping sys~.
There was extensive damage to electrical cables, trays and conduits.
There was extensive deposition of soot on all equipment located in the reactor building below the refueling floor. &is soot contained an estimated 1400 ponds of chloride.
All damage occurred in the reactor building outsice the contairment.
Based on its asmssnIent of the dunnage fran the fire, TVA has developed and carried out a program for restoration of Units 1 and 2.
This has consisted of r placing, from terminal to terminal, all damaged cables in the reactor protection system, primary containment isolation system and engineered safeguards sys~.
Some other cables that were damaged have been repaired by splicing.
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APPENDIX B Honorable William A. Anders March 11, 1976 Because of the extensive nature. of these xepairs it is extremely important that preoperational tests ascertain that repairs have been adequate to restore required functions.
Test procedures are being pxepared by TVA and are b ing reviamd by the >tR: Staff.
We ACBS wishes to be informed'f t¹ results of these tests prior to startup of Units 1 and 2.
A cleaning program has been carried out to ranove the soot, and tests have been conducted to determine davzge fran the soot.
While the cleaning program seems
- adequate, effects of the chlorides, such as stress corrosion
- cracking, may not be evident for sane timbre.
TVA has proposed a surveillance program to detect future deterioration that might be caused by these chlorides.
The KC Staff is reviewing the program to determine its adequacy.
Me ACRS emph mizes the importance of smh a program and wishes to be kept informed of the results.
Of the 9500 electrical co~actors
- involved, 45% have been replaced entirely and criteria for: splicing the remainder have been developed and followed.
Mditional heat and aroke detectors have been installed.
A fire retardant
- coating, Flamenastic 7lA, has been used to reduce flamnability.
Fire watches have been establis>M.
Autanatic fire protection sys~
and hand-held fire s~ession systems will be installed to prcrptly suppress fixes that may occur.
Mter spray vill be 'used at critical locations.
'Changes in ccmnunications are planned.
&e Caraittee believes that these represent significant improvements in fire protection.
Some of the fire control pxovisions and in particular -the gross application of Flmenastic 71A might involve long-term effects that warrant surveillance.
The cocoon~ of the electrical and control cables with Flaremastic 73A changes the working environment, and an arrangem nt for opening some portion of the cable bundles to inspect their condition periodically would seen to be appropriate.
The fire retardant action of the Flmemastic 73A has not been clearly descrBxd and, while tests indicate that it is effective, more information about its chemical be'havior in the presence of a fire would be desirable.
If the supplier of the material cannot provide the chemical infoxnation, the NBC Staff'should requ.st an independent laboratory to investigate its behavior as a pxecautio~ measure to determine the toxicity and corrosive pxoperties of the chemicals evolved during a fire.
The criteria for access for fire fighting purposes, while difficult to define, should be set forth by the NR: Staff for Applicants, so that there is a basis for judging the adequacy of the provisions.
the situation at Browns Ferry is governed largely by the already constructed installation, but t¹re may be opportunities for improving or modifying ~it is proposed.
APPENDIX B Honorable Willian A. Anders March 11, 1976 Since the TVA is self-insured in accordance with federal policy, its fnstallations do not have the normal fixe insurance surveillance used by private installations.
The TV@ has established an independent fire proteciion staff within its organization.
- Ramver, a newly established unit may not have either adequate status or experience to be wholly effective and should be supplemented by an. outside review agency to assure a broad and unconstrained evaluation of fire protection require-ments.
Verification of the adequacy of the fire protection training pxograms proposed by TVA should be part of the NRC regulatory plan.
The training program skuld include both initial-training and periodic retraining of personnel.
Following the Bro.ms Ferry fire the NRC Executive Director for Cperations set up a special review group to determine what should be learned fram this incident; This group has made recnmandations that amply to future
- reactors, to reactors that are already operating, and to the NRC regulatory process.
The review group points.out that its reccmardations axe not specific to any single plant and that its recamendations are ~ on knowledge at the time of this investigation.
&e ACRS wishes to be kept informed of t¹ specific application of th" review group s reco~<.
ndaticns as they apoly to Br&~s Ferry, to the development of additional informa-tion on fire prevention, fire fighting and quality assurance and the improvement of NRC policies, procedures and criteria.
The Qmaittee expects to xeviee generically several safety questions related to boiling water xeactors, including Park 1 torus response, during the next several months.
These questions as Gay may relate to Browns Ferry will be addressed in t¹ Gorrmttee's generic reports on these subjects.
Dhe Advisory Cannittee on Reactor Safeguards believes that, if due regard is given to the itens mentioned above, aa9 subject to satisfactory comple-.
tion of the planned re"toration and subsequent operatio~ testing, there is reasonable assurance that the Browns Ferry Nuclear Plant, Units 1 and 2, can b operated at power levels up to 3293 KM, subject to the conditions of the Committee's, reports of Septanber 21, 1972, and Decent.r ll, 1973, without undue risk to the health and safety of the public.
&Ma Dade W. Yeller Chairman
APPENDIX B Honorable William A. Anders March 11, 1976 References 34 "Plan for Evaluation, Repair, and Return to Service of Brcr~ns Ferry Nuclear Plant, Units 1 and 2 as a Result of the Yarch 22, 1975, Fire" by the Tennessee Vhlley Authority and Revisions 1 through 37 to that plan.
"Recomaendations Related to Browns Ferry Fire" (NUREG-0050)
Report by Special Review Group dated February 1976.
Safety Evaluation by the Division of 'Cperating Roactors Supporting the Cperation After the R storation and Nxlification of the Browns Ferry Nuclear Plant, Units 1 and-2 following the Parch 22, 1975, Pire dated February 23, 1976.
4, NRC letter to Tennessee Valley Authority dated bIay 9, 1975, issuing temporary Tech Specs for use during recovery from fire doge.
5.
6 70 Tennessee Valley Authority letter, dated June ll, 1975, regarding Qh provisions during cable splicing operations.
NRC letter. to Tennessee Valley.Authority dated June 13, 1975, modifying the Tech~ for the period. when Units 1 and 2 mre defu led and the.
fuel stored in the fuel pools.
Tennessee Valley Authority letter dated AUgust 18, 1975, forwarding responses to NRC questions relating to the Browns Ferry fire.
8.
9.
Tennessee Valley Authority letter dated August 21, 1975, cmaanting on the capability of obtaining total independence of redundant systens.
Tennessee alley Authority letter dated August 29, 1975, ccmnitting itself to certain actions.
- 10. Tennessee Valley Authority letter dated Septarher 15, 1975, formally caanitting TVA to actions regarding fire protection systans.
- 11. Tennessee Valley Authority letter dated November 17, 1975, regarding procedures for full-scale flame tests of wall penetration seal designs.
- 12. Tennessee Va3.ley Autturity letter dated %~her 8, 1975, regarding heat shield barrier design.
13.
NRC letter to Tennessee Valley Authority dated December 19, 1975, modifying the Tech~ to reflect reduced cooling requirerents for the Gml stored in the fuel pools.
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APPENDIX B Rgmrable Elilliam A. Anders March 11, 1976 References
. Continued
- 14. Tennessee Valley Authority letter dated January 15, 1976, transmitting data fran fire tests performed on candidate electrical cable wall penetration seal/fire stop designs.
- 15. Tennessee Valley Authority letter (undated) to B. C. Rusche transmitting Enclosures 1,
2 and 3 re:
R caarendations of fire consultants wd TVA responses; and additional information on the "Plan for Evaluation,
- Repair, and Return to Service of Browns Ferry Huclear Plant, Unit 1 and 2o
- 16. Tennessee Valley Authority consultant's (Associated Fire Protection Consultants, Inc.) letter reports dated February 25 and March 4, 1976.
17.
NRC letter'to ACRS dated March 4, 1976, forwarding the Story Report of the NRC's Fire Protection Consultant.
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36075 APPENDIX C
~ accri can$ pie identity Flamcrnastcr/FlayneTTTastic 71A Batch 030086 Date Rcccivcd 3/23 76 P,O. or R. k'. Nurnoor 5783 Work Order 6 51-01 Ship To:
Requested By Dr. Ro cr Peterson Sample Disposition Nature oi riasard Due Dace G Retain i3 Return g Destroy Flwinczclastcr Corp.
11120 Shcrcrali Way Sun Yalicy, Ca.
91352 Nature oi Y:ork and Liiormacion Desired l Dctcrrnine nature oE gaseolis combustion products.
Siunlnary oi ivaboracory 4 cport Q. C. Level Csc-..bustion tests indicate that Flarnemastic 71A does not propagate flam but biirns o!.Iy with difiicu'ty and is.selE extinguishing upon removal oE thc heat sou ce.
The pyrolysis-combustion process evolves a white smoke and leaves a dense char that makes complete combustion difficult. Chemical analyses of thc combustion products indicates carbon dioxide, *water, antimony chlorides, som hydrogen chloride, and traces of various chlorinated and other organic compoundsc A discussion oE the analytical methods is attached.
Most of the work was qualitative or semi-quantitative in nature due to time constraints.
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APPENDIX C, ANALYTICAL; PiESEA*'1CI) LABO'"1ATORI~S, fi'tC SPRVIC 160 TAYLOR STREET, P.O. BOX 369, MONROYIA, CALIFORNIA 91016
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f213) 3574247 Lab Log 36075, WO 69 51-0 1 Scope The following studies are of a general survey nature to develop the maximum useful information concerning pyrolysis-combustion char-acteristics of Flamemastic-71A in a short time.
Test Me hods A sa'mple of Flarnemastic 71A wa.s suspended on a wire and hcatcd with a gas burner until a dense white smoke was evolved.
Thc flang was then removed and the spec'imen was quickly covered with a gla.ss bell jar to trap the products of combustion and pyrolysis.
Thc experi-ment was thus designed to yield incompl'ete combustion in order to simulate conditions that might be expected in an actual plant fire.
The gases trapped under the bell jar were sampled and analyzed by mass spectrometry.
Qualitative chemical tests and emission spectro-xnetry were used to determine the natuie of the solid and liquid com-ponents.
Ressort s
Burning~Observations
- The specimen of 'Flamemastic 71A did not support flame propagation.
Holding it in a gas burner flame produced a heavy white smoke and only a small fla~e that was immediately
'xtingu-'shed upon removal of the burner flame.
The material subjected
.to the burner flame left a dense residual char indicating incomple e combustion.
Analysis:of Gaseous Combus ion Products
- Mass spectrometric analysis
- o t e atmosp ere and corn ustion gases trapped in the bell jar gave the
. foll'owing:
Vol. -%
N2 02 A
CO2 I
77..3
- 19. 9
- 0. 91 l.'83.
The above data indicate only slight combustion of the sample after remova>
of the burner as much excess air'is still present.
It is conccdcd that some Page 1 of 3'
APPENDIX C
~'Lab Log 36075, WO 6951-01 carbon monoxide also xnay bc present but not detected by mass pectro-metry in the presence of xnuch nitrogen.
In order to obtain an analysis of the minor amounts of organic species, a sample was concentrated by liquid nitrogen trapping to give the following:
. ~pzn
'Dichloro ethane 500.
Alcohol (probably CH3OH) 600.
Acetone 10.
Benzene 5.
Toluene 30.
Ethyl chio x ide 100.
~ Carbon tetrachloride 30.
Vinyl acetate"-
1, 000.
"-'Tentative. identification-the mass spectrum is consistent with the pxesence of vinyl acetate
- monomer, but further work is needed for unequivocal identification.
The above data indicate only the ratios and types of compounds produced under the laboratory burnino'pyrolysis conditions.
Concentrations and
'even species willvary widely with the degree of air dilution and.ac ual fire conditions.
Water and some hydrogen chloride axe expected in the burning of
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Flamemastic 71A, but these species were not detected by mass spectro-metry due to predictable surface adsorption retention.
-Analysis of Condensible Products
- The firing of a sample of Flame-mastic 71A gave a white smoke with minute aqueous droplets that were
~
condensed on a cold glass surface in a separate qualitative test.
The condensate gave a slight but definite test for strong acid but a much higher chloride level.
Emission spectrographic analysis of the white deposit confirms antimony as the major element with a minor of iron, and a trace of silicon.
Qualitative.ests also indicated the presence of traces of phosphates, as would be expected.
From the known formulation of the material, the above is readily
. explained.
Burning of the chlorinated hydrocarbons is known o pro-duce'hydrogen chloride and some does enter the atmosphere where it is quickly condensed as a hydrochloric acid mist in the presence oi the water from both the combustion and normal atmosphere.
iduch of the hydrogen chloxide, however, reacts with the antimony oxide under the fire conditions to produce, presumably, antimony trichloride.'". The he leva o
H 1 evolution is further reduced by the presence of calcium carbonate in thc formulation.
Pago 2 oE 3
APPENDIX C Lab Log 36075, WO 6951-0l insitu production of this material and i:s reaction with thc concurren"iy evolved moisture probably accounts for the white smolcc.
This heavy fume acts to retard combustion.
philo the quantitative compo itious of
, the smoke, or white deposit, was not determined, it probably consists mainly of a finely dispersed mixture of antimony chlorides, and oxy-cMorides; with some entrained oxide and aqueous hydrogen chloride mist.
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Pago 3 of 3
APPENDIX D COMPARISON OF BROWNS FERRY
." <NT, AS MODIFIED, WITH "RECOMMENDATIONS RELATED TO BROWN& r'j,"RRY FIRE REPORT BY SPECIAL REVIEW GROUP" (NUREG-0050)
NUREG-0050 Section 5 Pa e
Section 3.2 Criteria for Fire Prevention and Control 1.
Page 15 RECOb&KNDATION More comprehensive regulatory guidance is needed
- develop standards for acceptable fire protection design methodology.
RESPONSE
This recommendation concerns future guidance or requirements to be developed -by NRC.
When the guidance is forthcoming in the form of Regulatory Guides or when Standards or Regulations are issued on this topic, the area will be re-evaluated for the Browns Ferry Plarit to the same extent required for other licensed plants.
Section 3.3.1 Fire Prevention in Design 2.
Page 16 RECOMMENDATION Include measures to avoid potential problems with areas containing a high density of combustible material - provide system for maintaining an inventory of combustible material.
Assess combustible material in each safety-related area and take appropriate combination of measures for protection.
RESPONSE
TVA has assessed the installed combustible materials at the Browns Ferry Plant (Section 4.0 of SER) and provided measures including fire detection (Section 7.5.2 and 7.5.3), coating all exposed cable surfaces with a fire retardant material (Section 7.2), installing fixed water spray or sprinkler systems (Section 7.5.1),
adding fire hose stations to enhance coverage of accessible areas with combustible materials (Section 5.0), improved training, procedures, and organization for fire protection activities (Sect'ion 6.1, 6.2 and 6.3),
and an improved overall Quality Assurance Program (Section 6.4) to provide the proper amount of control of combustibles and extinguishment capability for the associated loading of installed combustibles.
For combustibles that are temporarily brought into areas of the plant,, administrative controls have been to increase the fire protection appropriately (Section 6.3).
3.
Page 16 RECOLREENDATION Alternative for future plants is establishment of fire zones arranged for adequate isolation of redundant safety equipment.
RESPONSE
This recommendation applies to future plants.
Section 3.3.2 Operating Considerations in Fire Prevention 4.
Page 16 RECOMMENDATION Measures avail.able for fire protection should be embodied in written procedures.
TVA has provided additional written procedures for fire protection (Section 6.2).
This recommendation has been incorporated in the Technical Specifications as a
requirement.
S.
Page 16 RECOMMENDATION Develop regulatory guides - allot review and inspection resources.
RESPONSE
This recommendation applies to the review of future plants and the re-review of the other operating plants and those for which licenses have already been requested.
Section 3.4 6.
Page 17 Criteria for Combustibility of Materials RECOMMENDATION More development work on materials and testing methods and development of selection criteria - decrease combustibility of present materials needing protection.
3-
RESPONSE
The basic objective of this recommendation is to decrease combustibility.
TVA has decreased the combustibility of present materials needing protection by the application of fire retardant coating to all exposed cable surfaces in all areas containing equipment required for safe shut-down (Section 7.2).
Section 3.4.1
. Cable Insulation Criteria 7.
Page 18 RECOMMENDATION Follow= Sandia and NELPIA-UL programs - Following completion of the programs implement changes in existing plants where significant safety improvement is indicated.
RESPONSE
8.
Page 18.
Ne intend to follow this recommendation..
RECOMMENDATION Include study of airborne products of heating and combustion in flammability investigations.
RESPONSE
This is a cable selection recommendation aimed at reducing the atmospheric release of such products.
TVA has used a
flame retardant coating to accomplish this purpose.
9.
Page 19 RECOMMENDATION Judicious use of fire retardant coatings - research and testing on coatings.
RESPONSE
TVA has provided an acceptable fire retardant coating for all exposed cable surfaces in all areas containing equipment required for safe shutdown (Section 7.2).
Section 3.4.2 Criteria for Fire Stops and Seals 10.
Page 21 RECOMMENDATION Develop qualification tests for individual materials as well as assembled fire stop - testing to be performed by qualified independent testing laboratory.
RESPONSE
We did not require testing by a qualified independent laboratory.
TVA conducted their own series of tests to develop a fire stop for Browns Ferry at the Watts Bar Test Facility.
NRC reviewed and approved these results (Section 7.4).
11.
Page 21 RECOMMENDATION Consider the possibility of providing fire stops at specified intervals in long cable trays.
RESPONSE
All exposed cable insulation surfaces in safety related areas have been coated with Flamemastic 71A providing essentially a continuous fire stop.
12.
Page 21 RECOMMENDATION Consider on a case-by-case basis removal of unapproved foam plastic seals.
RESPONSE
TVA has removed all polyurethane seal material to the extent practical.
Where polyurethane material is left it has been covered by at least six inches of the new seal material plus redundant barriers of insulation material (Section 7.4).
13.
Page 21 RECOMMENDATION Replace or demonstrate acceptability of extremely flammable material in fixe stops such as, the flexible polyurethane foam used as dams and plugs at Browns Ferry.
RESPONSE
All flexible polyurethane foam has been removed at Browns Ferry (Section 7.4).
14.
Page 21 RECOMMENDATION Seal all openings in control room in order to protect habitability.
RESPONSE
TVA has sealed.all openings in the control room and the ventilation system is designed to provide isolation for habitability (Section 7.4 and 7.5.7).
15.
Page 21 REC01ÃENDATION Consideration should be given to the addition of stops and seals in existing plants to reduce spread of fire,
- smoke, and gases.
RESPONSE
The Reactor Building is a complex structure with requirements for established ventilation patterns to achieve proper distribution and control of potential radioactivity.
There is no practical way to accomplish this recommendation for isolation of floors, etc.
The intent of the recommendation,'owever, i.e., to minimize the spread of the products of combustion, has been achieved by minimizing the contained combustible material including Flamemastic coating of exposed cables.
In addition, improvements have been made in fire related administrative procedures and automatic detection and extinguishment systems have been added.
Section 3.5.1 Fire Detection and Alarms Systems 16.
Page 22 RECOMMENDATION Assure compatability of smoke detectors with anticipated products of combustion.
RESPONSE
TVA is providing detectors that are UL approved for the application with the materials installed in the plant.
Design review and field surveys will have been made to assure proper location of detectors taking into account obstructions and air pockets.
(Section 7.5.3)
6-17.
Page 22 RECOMMENDATION Provide better guidance on fire detectors, preferably based on experiments with existing cables and detectors.
RESPONSE
This recommendation applies to future plants.
See response to Recommendation 18 below.
18.
Page 22 RECObRENDATION Review and upgrade, as necessary, installed fire detection systems in all plants.
RESPONSE
TVA has upgraded the fire detection systems in Browns Ferry (Sections 7.5.2 and 7.5.3).
Section 3.5.2 Design of Fire Extinguishing Systems
'19.
Page 24 RECOMMENDATION Emphasize need for quickly putting out all fires - factor into fire procedures and fire training.
RESPONSE
TVA has added fixed water spray and sprinkler systems for the purpose of providing a rapid means of distributing the extinguishing agent (lUater) to a cable fire.
(Section 7.5.1)
In addition, more fire hose racks have been installed and the training program and procedures, including prefire plans, now reflect an emphasis on the ability of water to extinguish cable fires.
(Section 6.1 and 6.2).
20.
Pages 24 6 25 RECOMMENDATION Recommend fixed extinguishing systems, automatic if feasible, in areas with high density of flammable material especially where access is difficult.
RESPONSE
TVA is providing such systems for BrownsFerry.
(Sections 7.5.1, 7.6.1, 7.6.2 and 7.6:3).
21.
Page 24 RECObMENDATXON Consider drainage needs and potential for water damage in design of water extinguishment systems.
RESPONSE
TVA has taken into account the drainage and sump capacity requirements associated with the spray and sprinkler systems.
"(Sections7.5.1, 7.6.1, and.7.6.3):
Protection of all safety related equipment from the effects of water drainage from operation of these systems was also taken into account by providing shields and covers where required.
(Sectiors 7.5.1 and 7.6).
22.
Page 24 RECObMNDATlON Develop guidance for specification of quality and design requirement for water sprinkler systems.
RESPONSE
Development of such guidance's unde&cay.
The adequacy of the Browns Ferry sprinkler system were reviewed and, as modified, are considered acceptable.
23.
Page 25 RECOM KNDATION Xn design of future plants, continue to provide high pressure water system (hoses,
- nozzles, hydrants) in all plant areas including those protected by sprinklers or sprays.
RESPONSE
At Browns Ferry, all areas, even those with sprays and sprinklers, will have water coverage available from at least two hose stations.
Section 3.5.3 Ventilation Systems and Smoke Control Page 25 RECOUP KNDATION Review and upgrade ventilation systems to (a) assure continued functioning if needed during a fire and (b) provide capability of isolating fires by cutout valves or dampers
- these provisions to be compatible with requirements for containment of radioactivity.
RESPONSE
The cable spreading rooms'entilation systems have been modified and meet this recommendation (Section 7.3).
The measures taken to protect against the two divisions of cabling from being affected by a fire (Section 7.0) ensure the availability of at least one Standby Gas Treatment System Train which could be utilized for ventilation in the Reactor Building.
The remainder of the areas required for safe shutdown of the plant have been evaluated and their emergency features for secondary containment isolation or for isolation to maintain habitability in the event of radioactive releases or smoke or toxic gas releases outside the area being protected, must retain priority over the capability to exhaust smoke (Section 7.5.7).
However, maintenance of ventilation systems operability has been enhanced by the prote'ction afforded from the fire-retardant coating of all exposed cable surfaces and other measures taken to reduce the effects of a fire.
Section 3.5.4 Fire Fighting 25.
Page 25 RECONIENDATION Include, in emergency plans, access and escape routes to cover event of a fire in critical plant area - Consider this aspect in design of future plants.
RESPONSE
TVA is providing prefire plans which include among other things the access and egress routes from areas of the plant where fires are likely to occur or where equipment related to safe shutdown of the plant is located.
(Section 6.2).
26.
Page 26 RECOMMENDATXON Assure cbmpatibility of fire fighting equipment with off site units.
RESPONSE
TVA has now installed equipment that is compatible with the
- Athens, Alabama Fire Department equipment.
- 27.
Page 26 RECOMMENDATION Review and upgrade, as necessary, available breathing equipment and means of recharging - consider this aspect in future designs.
RESPONSE
TVA has added requirement to the training program to ensure that the personnel know how to properly use breathing apparatus (Section 6.1).
TVA has also upgraded plant breathing apparatus charging capability from bottles and added a compressor charging system (Section 7.5.4).
Section 3.S.S Prevention and Readiness Efforts During Construction and Operation 28.
Page 26 RECOMMENDATION Develop plan for periodic testing of fire protection systems including individuals and their responsibilities.
RESPONSE
TVA has incorporated a testing program and schedule (Sections 6.2 and 6.3).
TVA also has provided a new position on the operating staff, one of encumbent's responsibilities is to ensure that the fire protection equipment is tested and maintained (Section 6.3).
29.
Page 26 RECOMMENDATION Include requirements for operability and surveillance testing of fire protection systems in Technical Specifications.
RESPONSE
The Technical Specifications for Browns Ferry will include operability and surveillance requirements for the fire protection systems (Section 8.0).
30.
Page 27 RECOMMENDATION Provide temporary measures when fire protection equipment is disabled for maintenance or when fire stops are breached.
RESPONSE
TVA has instituted administrative controls for providing supplemental fire ptorection measures when an installed fire protection or detection system is disabled for maintenance or when a fire stop is breached (Section 6.2)..
31.
Page 27 RECObMENDATION Emergency plans should recognize need for fire fighting concurrent with other activities.
RESPONSE
In regard to plans for fire fighting concurrent with other
. activities, TVA has reorganized the Fire Brigade (Section 6.3) to designate a specific portion of the operating shi:ft crew as Brigade members leaving the remaining portion of the operating shift for other activities associated with safe operation or shutdown of the plant.
32.
Page 27 RECOMMENDATION Conduct periodic fire drills to include onsite and offsite personnel and organizations that would normally respond to fires.
RESPONSE
The Browns Ferry Plant onsite fire fighting equipment and personnel
('plant fire brigade) are intended to be, and were found to be by our review, adequate without assistance from the offsite Athens Fire Department.
The offsite fire department is intended only as backup to onsite capability.
Agreements, plans and orientation visits to the Browns Ferry plant have been arranged with the Athens Fire Department;
- however, we do not require their participation in fire drills.
Periodic drills are held with the offsite TVA emergency organization and communications drills are made with non-TVA organizations.
Section 4.1.2 33.
Page 31 Role of Normal Cooling Systems RECOhÃENDATION Consider independence of normal and safety systems which could cool the reactor.
RESPONSE
Although this has never been an NRC review requirement, the Browns Ferry design demonstrated sufficient independence of normal systems to provide core cooling during and after the March 22, 1975 fire.
Our primary objective in the fire protection review was to assure that TVA had provided sufficient redundancy, diversity, and isolation within the divisional safety systems without reliance on other systems to assure reactor cooling in the event of a fire.
Section 4.2 34.
Page 32 Redundancy and Separation
- General Considerations RECOl+KNDATION Consider manual valve manipulation capability in design of all plants'.
Section 4.3.2
RESPONSE
This capability was considered and included in the original Browns Ferry design.
Common Mode Failures Attributable to Indicator Light Connections 35.
Page 36 RECOMMENDATION Recommends assurance of adequacy of isolation between safety equipment and non-safety circuits.
RESPONSE
The indicating lamp circuits which led to the loss of redundant Motor Operator Valve (h)OV) boards have been removed at Browns Ferry (Section 7.1).
Section 4.3.3.1 36.
Page 36 Trays and Conduit RECOMMENDATION Need improved criteria regarding use of conduit.
RESPONSE
Section 7.1 discusses the combined modifications at Browns Ferry to provide adequate conduit protection.
They include some relocation, coating of exposed cable surfaces and addition of fixed water systems to wet the conduit.
Section 4.3.3.3 Cable Spreading Room (CSR) 37.
Page 37 REC0%!ENDATION Need improvement in criteria for cable spreading room including separation andpccess for fire fighting.
RESPONSE
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~
SER Attachment 3(A.1, A.2) discusses improvements in'he Browns Ferry CSR protection.
They include automation of the C02 system, coating of all exposed cable surfaces and the addition of a back-up manual sprinkler system.
Section 4.3.4.1 Browns Ferry Criteria for Physical Separation and Isolation of Redundant Circuits 38.
Page 40 RECOMMENDATION Steel cable tray covers appear to be inadequate fire barriers.
RESPONSE
Fire barrier credit is not taken for cable tray covers in the Browns Ferry redesign.
Section 4.3.4.4 Criteria for the Future 39.
Page 42 RECOMMENDATION Improve existing NRC separation and isolation criteria.
h
- 13>>
40.
Page 4S
RESPONSE
This is a recommendation for the future not applicable here.
RECOMMENDATION Practical to provide separate cable spreading rooms for each division in future plants.
RESPONSE
This is a recommendation for the future not applicable to this plant.
41.
Page 46 RECOMMENDATION Separate redundant manual control switches by suitable fire barriers.
RESPONSE
Although this is a recommendation for the future, we noted that the redundant manual control switches at Browns. Eerry have canned enclosures and have a minimum separation of
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6 inches air space.
Ãe have not required additional fire barriers for this plant.
Section 4.4 42.
Page 47 Instrumentation Required for Operator Action RECOMMENDATION Urges NRC and industry standard groups to develop standards and requirements for instrumentation required for operator information and action.
RESPONSE
This is a recommendation for the future. Such standards and requirements when developed will be considered to the extent applicable.
Section S.2 43.
Page 49 Lapses in Quality Assurance at Browns Ferry RECOMMENDATION Reevaluate revised Browns Ferry QA program in light of experience of the fire.
RESPONSE
TVA has a new QA program for Operations which meets the current NRC requirements.
In addition, OIOE willverify that the appropriate portions of the detailed QA Procedures Manual have been modified to address the area of fire protection.
r 44.
Page 50 RECOMMENDATION Operating QA programs in older reactors, known not to conform to current standards, should be upgraded promptly.
45.
Page 50
RESPONSE
The Browns Ferry program has been upgraded.
RECOMMENDATION Upgrade the NRC Inspection program.
RESPONSE
The NRC inspection program for the restoration and modification at Browns Ferry has been upgraded to include fire protection systems, fire prevention, and fire fighting.
46.
Page 50 RECObMNDATION Licensee QA programs, and NRC licensing and inspection programs should include explicit reference to fire prevention, fire fighting and consequences mitigation in their written procedures.
RESPONSE
The NRC licensing and inspection programs for the Browns Ferry restoration and modifications explicitly evaluate fire prevention, fire fighting, and fire prevention and the SER and its supplements and the inspection reports provide written evidence of this.
0 r Section 5.3.1.2 Offsite 47.
Page 51 RECOMMENDATION Consideration should be given to providing alternate or emergency power supplies for fixed in-plant radiological monitoring equipment or providing sufficient manpower for use of portable monitors.
RESPONSE
TVA is prepareing emergency procedures to provide added presonnel and portable equipment.
48.
Page 51 RECONIENDATION "Standby" classification in emergency plans appears necessary to cover those incidents (like the fire) with potential for later triggering one of the four major incident classification categories.
RESPONSE
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TVA is changing their Emergency Procedures to provide for a "standby alert" condition.
Section.6.2.3 NRC Organization - Application to Unusual Events and Incidents 49.
Page 54,60 RECOMMENDATION Improve NRC procedures for the safety review of incidents.
Clarify the concept of "Lead responsibility".
RESPONSE
015E and ONRR are now holding regular monthly meetings to.
discuss issues as they arise regarding interface relationships between the offices.
As an outgrowth of these meetings, new written guidelines are under development defining more clearly the responsibility for these interface areas.
>>16-50.
Page 55 RECOMMENDATION Implementation of Review Groups recommendations must be decided plany-,by-plant.
RESPONSE
This tabulation together with the SER for the return to
.operation of Browns Ferry shows the implementation of the SRG recommendations appropriate for this plant at this time.
As the staff implements additional SRG recommendations in the future, the need for further action for this plant as well as others, will be considered.
Section 6.3 51.
Page 56 NRC Action Before the Fire RECOMMENDATION Present NRC programs in fire prevention and control research, standards and criteria, licensing and inspection should be continued and expanded as needed and as recommended in report.
RESPONSE
Additional fire protection requirements generated by such continued and expanded efforts will be considered for this plant to the extent that significant improvements in safety can be achieved.
Section 6.3.3 52.
Page 57 Inspection of Licensee Operations REC01$ ENDATION Reevaluate procedures for resolution by NRC..management of issues involving "poor practice" findings by inspectors.
RESPONSE
The staff recognizes the need for NRR to responsibly deal with "feedback" from IE inspectors and where appropriate, will develop enforceable criteria and requirements applicable to this and other nuclear power plants.
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~ e Section 6.4 NRC Action During and After the Fi.re 53.
Page 58 RECOMMENDATION Develop alternate modes of transportation for emergency use to avoid undue delays between a region office and a site.
RESPONSE
Alternative methods of transporatation from house or Regional Office to the affected nuclear site at any hour are being evaluated.
The objective is to assure dispatch of appropriate personnel within two hours after notification.
54.
Page 58 RECOhÃENDATION V
Give attention to availability of back-up management and technical personnel at Headquarters to provide for a prolonged emergency.
RESPONSE
Duty Officers are being established in all the offices necessary to respond to any emergency.
55.
Page 58 RECOMMENDATION Provide improved communications facilities - start with a system study.
RESPONSE
An Incident Management Center(IMC) has been established in the IE Headquarters Office in Bethesda, The Center houses the existing communications equipment for incident manage-ment, which consists of telephones with arrangements for conference calls.
During emergency periods, the NRC operators'ervices are available for assisting the IMC on an augmented basis.
Four of the IE principal staff and the IE Duty Officers have been assigned papers for prompt response to messages.
Two facsimile machines and communicating magnetic aard typewriters are located within the IE offices.
Procedures for notification of their agencies are in effect.
4t 18-Acquisition of communications facilities and development of procedures necessary to establish a link between Headquarters, Regions and the incident site remains to be accomplished.
ATILT consultation for the discussion of operational needs and equipment has been arranged.
Internal procedures are under development.
Section 7.0 56.
Page
'61
Response
to Other Government Agencies RECOMMENDATION Alabama and local governments should reassess and strengthen emergency notifications methods and procedures.
RESPONSE
Meetings have been held with the Alabama and local officials and training sessions and drills have'een held with the appropriate emergency personnel.
,Section 7.2.2 Tennessee 57,.
Page 62 RECOMMENDATION
'TVA emergency spokesman need to use more careful phraseology
'to avoid inciting undue alarm in offsite agencies.
RESPONSE
58.
Page 63 This recommendation has been passed on to TVA.
RECOMMENDATION Recommend continued efforts for helping States develop radiological emergency response plans.
Section 7.3.6 59.
Page 64
RESPONSE
Efforts are continuing in this area.
Drills and Exercise RECOMMENDATION Recommends that drills and exercises to test emergency interface between TVA, the State of Alabama and its local governments be conducted at least annually.
A A o RESPONSE TVA plans to make these periodic drills more effective to ensure full communications coverage.
60.
Page 7-11 RECOI4KNDATZON Other licensees should also initiate adequate regular excercises to promote maintenance of emergency response capability by local government.
RESPONSE
This recommendation is for'other licensees.
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