ML18033B201

Proposed Tech Specs Re Standby Gas Treatment Sys & Secondary Containment Sys

ML18033B201
Person / Time
Site:	Browns Ferry
Issue date:	03/06/1990
From:	TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML18033B199	List: ML18033B198 ML18033B201
References
NUDOCS 9003130382
Download: ML18033B201 (33)

Text

CO 82'8 MS I l LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS I,

3.7.B. Sta sT ate te 4.7.8.

I b Gas T eatmen S Except as specified in l. At least once per year, Specification 3.7.B.3 below, the following conditions all three trains of the shall be demonstrated.

standby gas treatment system shall be OPPRABLE at all a. Pressure drop across times when secondary the combined HEPA containment integrity is filters and charcoal re~uired. adsorber banks is less than 6 inches of water at a flow of 9000 cfm (g 107').

b. The inlet heaters on each circuit are tested in accordance with ANSI N510-1975, and are capable of an output of at least 40 kW.

c. Air distribution is uniform within 20Ã across HEPA filters and charcoal adsorbers.

BFN 3. 7/4. 7-13 Unit 1 9003130382 900306 PDR ADOCK 05000259 P. PDC

1 I

I 7'TAI S S E LIMITINQ CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS

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3.7.8, T ea S I'db et 4.7.B. Sta ea

~~te 4.7.B.2 (Cont'd)

d. Each train shall be operated a total af et least 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> every month.

e. Test sealing of gaskets far housing doorsh shall be performed utilizing chemical smoke genera-tors during each test performed for campliance with Speci-fication 4.7.B.2.a and Specification 3.7.B.2.a.

3 ~ Prom and after the date that 3 ' ~ Once per operating cycle one train of the standby gas automatic initiation. of treatment system ie made or each branch af the stand-found to be inoperable fox any by gas treatment system reason, REACTOR POWER OPERATION shall be demonstrated fuel handling is permissible 'nd from each unit's controls, anly during the succeeding 7 days unless such circuit is b. At least once per year sooner made OPERABLE, provided manual operability of that during such 7 days all the bypass valve for active components of the other filter cooling shall be two standby gas treatment trains demonstrated.

shall be operable.

C~ When one train of the standby gae treatment system becomes inoperable the other two trains shall be demonstx'ated to be OPERABLE within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and daily thereafter.

4. If these conditions cannot be met:

a. suspend all fuel handling operations, core alteratians, and activities with the potential to drain any reactor vessel containing fuel.

BFN 3.7/4.7-15 Unit 1

C YS E LIMITING CONDITIONS FOR OPERATION SURVEILLANCE RE/UIRENENTS

~ ~

3,7.B. S b G eat ,4.7.B. Gas 3.7.B.4 (Cont d) b, Place all reactors in at least a HOT SHUTDOWN CONDITION within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in a COLD SIIUTDOMH CONDITION within tho following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

4.7.C. econda ice

1. Secondary containment integrity 1. Secondary containment shall be maintained in the surveillance shall be reactor zone at all times performed as indicated except as specified in below:

3.7oCi2.

a. Secondary containment capability to maintain 1/4 inch of water vacuum under calm wind (< 5 mph) conditions with a system leakage rate of not more than 12,000 cfm, shail be demonstrated at each refueling outage prior to refueling.

2. If reactor zone secondary 2. After a secondary containment integrity cannot containment. violation is be maintained the following determined, the standby gas conditions shall be met: treatment system will be operated immediately after

a. Suspend all fuel handling the affected zones are operations, core alterations, isolated from the remainder and activities with the potential of the secondary to drain any reactor vessel containment to confirm its containing fuel. ability to maintain the remainder of the secondary b, Restore reactor zone secondary containment at 1/4-inch containment integrity within 4 of water negative pressure hours, or place all reactors in under calm wind conditions.

at least a HOT SHUTDOWN CONDITION within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in a COLD SIIUTDOWH CONDITION within the following 24 hours.

3. Secondary containment integrity sha11 bo maintained in the refueling zone, except as specified in 3.7.C.4.

BFN 3.7/4.7-16 Unit 1

~

~

CO TE S I

LIMITINQ CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS I ~

3.?, C, on onta t )

4. If refueling zone secondary containment cannot be maintained the following conditions shall be met:

a. Handling of spent fuel and all operations over spent fuel pools and open reactor wells containing fuel shall be prohibited.

b. The standby gas treatment system suction to the refueling zone will be blocked except for a controlled leakage area sized to assure the achieving of a vacuum of at least 1/4-inch of water and not over 3 inches of water in all three reactor zones, This is only appli-cable if reactor zone inte-grity is required.

ar ai Ieo a Ua v D. r Cont so t Ua ve

1. When Primary Containment 1. The primary containment Integrity is required, all isolation valves isolation valves listed in surveillance shall be Table 3.?.A and all reactor performed as follows; coolant system instrument line flow check valves shall be a. At least once per OPERABLE except as specified operating cycle, the  !

in 3.?.D.2, OPERABLE isolation valves that are power operated and automatically initiated shall be tested for simu-

~

lated automatic initiation and in accordance with Specification 1.0.MM, tested for closure times, BFN 3.?/4.?-1?

Unit 1

'.7/4,7 /USES (Cont'd The primary containment leak rate teat frequency is based on maintaining adequate assurance that the leak rate remains within the specification, The leak rate test frequency is baaed on the NRC guide for developing leak rate testing and surveillance of reactor containment vessels, Allowing the test intervals to be extended up to 10 months permits some flexibilityneeded to have the teats coincide with scheduled or unscheduled shutdown periods.

The penetration and air purge piping leakage test frequency, along with the containment leak rate testa, is adequate to allow detection of leakage trends. Whenever a bolted double-gaaketed penetration ia broken and remade, the space between the gaskets ia pressurized to determine that the seals are performing properly. It is expected that the ma)arity of the leakage fram valves, penetratione and seals would be into the reactor building,. However, it is possible that leakage into other parts of the facility could occur.

Such leakage paths that may affect significantly the consequences of accidents are to be minimized.

The primary containment is normally slightly pressurized during periad of reactar operation, Nitrogen used for inerting could leak out of the containment but air could not leak in to increase oxygen concentration. Once the cantainment ie filled with nitrogen to the required concentration, determining the oxygen cancentration twice a week serves as an added assurance that the oxygen concentratian will not exceed 4 percent.

3,7.B/3.7.C ndb Trea t S a and Se dar Con ent The secondary containment is designed to minimize any ground level release of radioactive materials which might result from a serious accident. The reactor building provides secondary containment during reactor operation, when the drywell is sealed and in service; the reactor building provides primary containment, if required, when the reactor ie shutdown and the drywell is apen. Because the secondary containment is an integral part of the complete containment system, secondary containment is required at all times that primary containment ia required as well as during refueling.

The standby gas treatment system is designed to filter and exhaust the reactor building atmosphere to the stack during secondary containment isolation conditions. All three standby gas treatment system fans are designed to automatically start upon cantainment isolation and to maintain the reactor building pressure to the design negative pressure ao that all leakage should be in-leakage, High efficiency particulate air (HEPA) filters are installed before and after the charcoal absorbers to minimize potential release of particulates to the environment and to prevent clogging of the iadine absarbera. The charcoal absorbera are installed to reduce the potential release of radioiodine to the environment. The in-place test results should indicate a system leak tightneea of lese than 1 percent bypass leakage for the charcoal absorbers and.

a HEPA efficiency of at least 99 percent removal of DOP particulates. The laboratory carbon sample test results should indicate a radioactive methyl iodide removal efficiency of at least 90 percent for expected accident conditions. If the efficiencies of the HEPA filters and charcoal absorbera are as specified, the resulting doses will be less than the 10 CFR 100 guidelines for the accidents analyzed. Operation of the fans significantly different from the design flow vill change the removal efficiency of the HEPA filters and charcoal abaorbers.

BFN 3.7/4.7-4 I Unit 1

'I 1 f kg

3,7/4.7 BM~ (Cont'd Only twp of the three standby gas treatment systems are needed to clean up the reactor building atmosphere upon cantainment isolation. If ane system is found to be inoperable, there is'o immediate threat ta the containment system performance and reactox aperatian or refueling opex'ation may continue while repairs are being made. If morc than one train is inoperable, all fuel handling operations, core altexations, and activities with the potential ta drain any reactor vessel containing fuel must be suspended and all reactors placed in a cold shutdown condition, because the remaining train would provide only 50 pexcent of the capacity required to filter and exhaust the reactor building atmosphere to the stack. Suspension of these activities shal1 not preclude movement of a component to a safe, conservative position. Operations that have the potential for draining the reactor vessel must be suspended as soon as practical ta minimize the probability of a vessel draindown and subsequent patential for fission pxoduct release. Draindown of a reactor vessel containing no fuel does not present the possibility for fuel damage ox'ignificant fission product release and therefore is nat a nuclear safety concern, 4.7.B/4.7.C Sta Gas eatmen stem Second Contai Initiating reactor building isolation and operation af the standby gas treatment system to maintain at least a 1/4 inch of water vacuum within the secondary containment provides an adequate test of the operation af the reactor building isolation valves, leak tightness of the reactar building and performance of the standby gas treatment system, Functionally testing the initiating sensors and.

associated trip logic demonstrates the capability for automatic actuation.

Performing these tests prior to refueling will demonstrate secondary'y containment capability prior to the time the primary containment is opened for refueling, Pex'iodic testing gives sufficient confidence, of reactor building integrity and standby gas treatment system performance capability.

The test frequencies are adequate to detect equipment deterioration prior to significant defects, but the tests are not frequent enough to load the filters, thus reducing their reserve capacity too quickly, That the testing frequency is adequate to detect deterioration was demonstrated by the teats which showed no loss of filter efficiency aftex two years of operation in ~~~~ed shipboard environment an the US Savannah (ORNA ~). Pressure drop across the cambined HEPA filters and charcoal adsorbers of less than six inches of water at the system design flow rate will indicate that the filters and adsorbers are not clogged by excessive amounts of foreign matter. Heater capability, pressure drop and air distribution should be determined at least once per operating cycle to show system perfoxmance capability.

The frequency af tests and sample analysis are necessary to show that the HEPA filters and chaxcoal adsorbers can perform as evaluated. Tests of the charcoal adsaxbexs with halogenated hydrocarbon refrigerant shall be performed in accordance with USAEC Report DP-1082. Iodine removal efficiency testa shall follow ASTM D3803. The charcoal adsorbex efficiency test procedures ~au~1 allow for the removal of ads er tx , emptying of one bed from the tray, mixing the adsarbent thoroughly and. obtaining at least two samples. Each sample should be at least two inches in diameter and a length equal ta the thickness of the bed. If test results are unacceptable, all adsorbent in the system shall- be replaced with an adsorbent qualified according to Table 1 of Regulatory Guide 1.52, The replacement tray for the adsorber tray removed for the test should meet the same adsorbent quality. Tests of the HEPA filters with DOP aexosol shall be performed in accoxdance to ASSI N510-1975. Any HEPA filters found defective shall be replaced with filters qualified puxsuant to Regulatory Position C.3.d of Regulatory Guide 1.52.

BFH 3.7/4.7-48 Unit 1

4 0

4 0 S S 1 ~

LIMITIMCONDITIONS FOR OPERATION r

SURVEILLANCE REQUIREMENTS 3.7.B. St b rea m t S st 4.7.8. andb eat e S ste I. Except as specified in l. At least once per year, Specification 3.7.8.3 below, the following conditions all three trains of the shall be demonstrated.

standby gas treatment syst: em shall be OPERABLE at all a. Pressure drop across times when secondary the combined HEPA containment integrity is filters and charcoal required. adsorber banks is less than 6 inches of water at a flow of 9000 cfm (Z IOX).

b. The inlet heaters circuit are on'ach tested in accordance with ANSI N510-1975, and are capable of an output of at least 40 kw,

c. Air distribution is uniform within 20K across HEPA filters and charcoal adsorbers.

BFN 3,7/4.7-13 Unit 2

0 CO A S S MS LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS I" ~ ~

t ndb reatm te

'.7.B.

4.7.B. Ga e 4.7.B.2 (Cont'd) d, Each train shall be operated a total of at least 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> every month.

Test sealing of gaskets for hausing doors shall be performed utilizing chemical smoke generators during each test per-formed for campliance with Specification 4.7.8.2.a and Specifi-cation-3.7.B.2.a.

3. From and after the date that 3 ~ ao Once per operating cycle one train of the standby gas automatic initiation of treatment system is made or each branch of the found to be inoperable for any standby gas treatment reasan, REACTOR POWER OPERATION system shall be and fuel handling is permissible demonstrated from each only during the succeeding 7 unit's controls, days unleee such circuit is sooner made OPERABLE, provided b. At least once per year that during such 7 days all manual operability af active components of .the other the bypass valve for two standby gae treatment trains filter cooling shall be shall be OPERABLE. demonstrated.

c. When one train of the standby gas treatment system becames inoper-able the other twa trains shall be demon-strated to be OPERABLE within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and daily thereafter.

4. If these conditions cannot be met:

a, Suspend all'uel handling operations, care alterations, and activities with the potential to drain any reactor vessel containing fuel.

BFN 3.7/4,7-15 Unit 2

1 LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS l I ~

3.7.B, Gas T e S e 4.7.B. St ndb t st 3.7.B.4 (Cont'd)

b. Place all reactors in at least a HOT SHUTDOMN CONDITION within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in a COLD SHUTDOWN CONDITION within the following 24 haurs.

3,7.C. da C . ent 4.7,C, Sec ent

1. Secondary containment integrity 1. Secondary containment shall be maintained in the surveillance shall be reactor zane at all times performed as indicated except as specified in below; fI 3.7.C.2,

a. Secondary containment capability to maintain l/4 inch of water vacuum under calm wind (< 5 mph) conditions with a system leakage rate of not more than 12,000 cfm, shall be demanstrated at each refueling outage priar to refueling.

2. If reactor zone secondary 2. After a secondary containment integrity cannot containment violation is be maintained the following determined, the standby gas conditians shall be met: treatment system will be operated immediately after

a. Suspend all fuel handling the affected zones are aperations, care alterations, isolated fram the remainder and activities with the potential of the secondary to drain any reactor vessel containment to confirm its containing fuel. ability to maintain the remainder of the secondary b, Restore reactor zone secondary containment at 1/4-inch containment integrity within 4 of water negative pressure hours, or place all reactors in under calm wind conditions.

at least a HOT SHUTDOVN CONDITION within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in a COLD SHUTDOWN CONDITION within the following 24 haurs.

3. Secondary containment integrity shall be maintained in the refueling zane, except as specified in 3.7.C.4.

BFN 3.7/4.7-16 Unit 2

~ CO LIMITING CONDITIONS FOR OPERATI(N. SURVEILLANCE REQUIREMENTS 1

3.7.C. ond Co t

4. If refueling zone secondary containment cannot be maintained the following conditions shall be met:

a. Handling of spent fuel and all opex'ations aver spent fuel pools and open reactar wells containing fuel shall be prohibited.

b. The standby gas treatment system suction to the refueling zone will be blocked except far a cantrolled leakage area sized to assure the achieving of a vacuum of at least 1/4-inch of water and not over 3 inches of water in all three reactor zones. This is only appli-cable if reactor zone integrity is required.

D. rimar C nt Iso at o es D. r mar Co at on Valves

1. Mhen Primary Containment l. The primary cantainment Integrity is required, all isolation valves isolation valves listed in surveillance shall be Table 3.7.A and all reactor pex formed as follows; coolant system instrument line flow check, valves a. At least once per.

shall be OPERABLE except as operating cycle, the specified in 3.7.D.2. OPERABLE isolation valves that are power operated and automatically initiated shall be tested for simulated automatic initiation, and in accordance with Specification 1.0.MN, tested for clasure times.

BFN 3.7/4.7-17 Unit 2

'.7/4.7 g~'S (Cane'd The adequate t

primary containment leak rate teat frequency is baaed on maintaining assurance that the leak rate remains within the specification. The leak rate test frequency is based on the NRC guide for developing leak rate and surveillance of. reactor containment vessels, 1'esting Allowing,,the teat intervnla to be extended up to 10 months permits some flexibility needed to have the teats coincide with scheduled or unscheduled shutdown periods.

The penetration and air purge piping leakage teat frequency, along with the containment leak rate tests, is adequate to allow detection of leakage trends. Whenever a bolted double-gasketed penetration ia broken and remade, the space between Che gaskets is pressurized to determine that thc seals are performing properly. It ia expected that the majority of the leakage from valves, penetrntiona and seals would be into the reactor building. However, it is possible that leakage into other parts of the facility could occur.

Such leakage paths that may affect significantly the consequences of accidents are to be minimized.

The primary containment is normally slightly pressurized during period of reactor operation. Nitrogen used. for inerting could leak out of t'e containment but air could not leak in to increase oxygen concentration. Once the containment ia filled with nitrogen to the required concentration, determining the oxygen concentration twice a week serves as an added assurance that the oxygen concentration will not exceed 4 percent.

3.7.B/3,7.C Stand as Trea ent S ate and Secon Containme The aec6ndary containment is designed Co minimize any ground level release of radioactive materials which might result from a serious accident. The reactor building provides secondary containmenc during reactor operation, when the drywell ia sealed nnd in service; the reactor building provides primary containment, if required, when the reactor ia shutdown and the drywall is open. Because the secondary containment is an integral part of Che complete containment system, secondary containment is required at all times that primary containment is required as well as during refueling.

'I The standby gna treatment system is designed co filter and exhaust the reactor building atmosphere to the stack during secondary containment isolation conditions. All three standby gas treatment system fans are designed to automatically start upon containment isolation and to maintain the reactor building pressure to the design negative pressure ao Chat all leakage should be in-leakage.

High efficiency particulate air (HEPA) filters are installed before and after the charcoal abaorbera.to minimize potential release of particulates to the environment and to prevent clogging 'of the iodine absorbera. The charcoal nbsorbera nre installed to reduce the potential release of radioiodine co the environment. The in-place test results should indicate a system leak tightness of less than 1 percent bypass leakage for the charcoal nbaorbere and a HEPA efficiency of nt least 99 percent removal of BOP particulates, The laboratory carbon sample test results should indicate n radioactive methyl iodide removal efficiency of at least 90 percent for expected accident.

conditions. If the efficiencies of the HEPA filters and charcoal abaorbera are aa specified, the resulting doses will be less than the 10 CFR 100 guidelines for the accidents analyzed. Operation of the fans significantly different. from the design flow will change the removal efficiency of the HEPA filters and charcoal absorbera.

BFN 3.7/4.7-47 Unit 2

3.7/4.7 B~ES (Cont'd) ~

.Only two'of the three standby gne treatment systems are needed to clean up the reactor building atmoephexe upon containment isolation. If one system is found to be inoperable, there ia~ no immediate threat to the containment system pexformance nnd reactor operation or refueling operation may continue while repairs are being made. If more than one train ie inoperable all fuel handling operations, core alterations, nnd activities with the potential to drain any xeactor vessel containing fuel must be suspended nnd all reactors placed in a cold shutdown condition, because the remaining train would provide only 50 percent of the capacity required to filter nnd exhaust the reactor building atmosphere to the stack. Suspension of these activities shall not preclude movement of n component to n safe, conservative position. Operations that have the potential for draining the reactor vessel must be suspended aa soon ne practical to minimize the probability of a vessel drnindown and subsequent potential for fission product xeleaae. Draindown of n reactor vesee1 containing no fuel does not present the possibility for fuel damage or significant fission product release and therefore is not a nuclear safety concern.

4.7.B/4i7.C andb Treatment tern nnd Se Containm Initiating reactor building isolation and operation of the standby gaa

~

treatment .system to maintain at least a 1/4 inch of water vacuum within the secondary containment provides an adequate test of the operation of the reactor building isolation valves, leak tightness of'he reactor building and performance of the at:nndby gaa"treatment system. Functionally testing the initiating sensors nnd associated trip logic demonstrates the capability for automatic nctuation, Performing these tests prior to refueling will demonstrate secondary containment capability prior to the time the primary containment ie opened for refueling. Periodic testing gives sufficient confidence of reactor building integrity and standby gaa treatment system pexformance capability.

The test frequenciea are adequate to detect equipment; detexioxation prior to significant defects, but the teste are not frequent enough to load the filtere, thus reducing their reserve capacity too quickly. That the testing frequency .is adequate to detect deterioration was demonstrated by the tests which showed no 1oss of filter efficiency after two yeaxa of operation in g~ru~e shipboard environment on the US Savannah (~OJg~2+). Pressure drop across the combined HEPA filters and charcoal'dsorbers of lese than six inches of water at the system design flow rate will indicate that the filters and ndsorbere are not clogged by excessive amounts of foreign mattex'.

Heat:er capability, pressure drop and air distributi,on should be determined at least once per operating cycle to show system performance cnpabi1ity.

The frequency of tests and sample analysis are necessary to show that the HEPA filters and charcoal ndeorbexa can perform as evaluated. Testa of the chaxcoal ndsorbera with halogenated hydrocarbon refrigerant shall be performed in accoxdance with USAEC Report DP-1082. Iodine removal efficiency teats ehail follow ASTM D3803. The charcoal adaorbex efficiency test procedures ahho S.g allow for the removal of d orber , emptying of one bed from the tray, mixing the adsorbent thoroughly nnd obtaining at least two samples.

BFN 3.7/4.7-48 Unit 2

c+

CO E S LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS 4.7.B. Sta re S ste

1. Except as specified in l. At least once per year,

! Specification 3,7.8.3 belov, the following conditions all three trains of the shall be demonstrated.

standby gas treatment system shall be OPERABLE at all a. Pressure drop across times when secondary the combined HEPA containment integrity is filters and charcoal required. adsorber banks is less than 6 inches of vater at a flov of 9000 cfm (g 104).

b, The inlet heaters on each circuit are tested in accordance with ANSI N510-1975, and are capable of an output of at least 40 kM.

c. Air distribution is uniform within 20K across HEPA filters and charcoal adsorbers, BFN 3.7/4,7-13 Unit 3

CO

' LIHITINQ CONDITIONS FOR OPERATIOH SURVEILLANCE REQUIRENENTS

,.4.7.B. Ga ent 4.7,B.2 (Cont'd) d ~ Each train shall be operated a total of at least 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> every month.

e. Test sealing of gaskets for housing dooxs shall be performed utilixing chemical smoke genera-tors during each test performed for compliance with Specification 4.7.8.2.a and Specifi-cation 3.7.B.2,a.

3. From and after the date that one 3 ~ ao Once per operating cycle train of the standby gae treat-...-;- automatic initiation of ment system is made or found to each branch of the be inoperable for any reason, standby gas treatment REACTOR POWER OPERATION and fuel system shall be handling is permissible only demonstrated from each during the succeeding 7 days unit's contxols.

unless such circuit is sooner made OPERABLE, pxovided that At least once per year during such 7 days all active manual operability of components of the other two the bypass valve for standby gas treatment trains filter cooling shall be shall be OPERABLE. demonstrated, co Mhen one train of the standby gas treatment system becomes inoper-able the other two trains shall be demon-strated to be operable within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and daily thereafter.

4. Xf these conditions cannot be met:

a. Suspend all fuel handling operations, core altexations, and activities with the potential to drain any

'reactox'essel containing fuel.

BFH 3.7/4.7-1S Unit 3

'4 0 8 S

~

LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIRMEKZS 37B, ad s e 4.7.B. St Gas

~Ss gg 3.7.B,4 (Cont'd)

b. Place all reactors in at least: a HOT SHUTDOWN CONDITION within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in a COLD SHUTDOWN CONDITION within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

3.7.C. afnm 4.7.C.

1. Secondary containment integxity l. Secondary containment shall be maintained in the surveillance shall be reactor zone at all times performed as indicated except as specified in below:

3.7.C.2.

a. Secondary containment capability to maintain 1/4 inch of water vacuum under calm wind

(< 5 mph) conditions with a system inleakage rate of not moxe then 12,000 cfm, shall be demonstrated at each refueling outage prior to refueling.

2. If reactor zone secondary 2. After a secondary containment integrity cannot containment violation is be maintained the following det:ermined, the standby gas condit;ions shall be met: treatment system vill be operated immediately after a, Suspend all fuel handling oper- the affected zones are ations, core alterations, and isolated from the remainder activities with the potential of the secondary to drain any reactor vessel containment to confirm its containing fuel. ability to maintain the remainder of the secondary b, Restore reactor zone secondary containment at 1/4-inch containment: integrity within 4 of water negative pressure hours, or place all reactors in under calm wind conditions.

at: least a HOT SHUTDOWN CONDITION within the next 12 houxs and in a COLD SHUTDOWN CONDITION within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

3. Secondary containment integrity shall be maintained in the refueling zone, except as specified in 3.7.C.4.

BFN 3,7/4.7-16 Unit 3

ae 4

e LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS I ~

3.7.C, ndar t

4. If refueling zone secondary containment cannot be maintained the following conditions shall be met:

a. Handling of spent fuel and all operations over spent fuel pools and open reactor wells containing fuel shall be prohibited.

b. The standby gas treatment system suction to the refueling zone will be blocked except for a controlled leakage area sized to assure the achieving of a vacuum of at least 1/4-inch of water and not over 3 inches of water in all three reactor zones. This is only applicable if reactor integxity is required, zone D. ri ent at o ves D. P i Co t V~av e s

1. Hhen Primary Containment 1. The primary containment Integrity is required, all isolation valves isolation valves listed in surveillance shall be Table 3,7.A and all reactor performed as follows:

coolant system instrument line flow check valves a. At least once per shall be OPERABLE except as operating cycle, the specified in 3.7.9.2, OPERABLE isolation valves that are power operated and automatically initiated shall be tested for simulated automatic initiation and in accordance with Specification 1.0.MM, tested for closure times.

BFN 3. 7/4. 7-17 Unit 3

3.7/4.7

', The R~S (Cont'd t primary containment leak rate test fxequency ia baaed on maintaining adequate assurance that the leak rate xemains within the specification, The leak rate test frequency is baaed. on the HRC guide for developing leak rate testing and surveillance of reactor containment vessels. Allowing the teat intervals to be extended up to 10 months pexmits some flexibilityneeded to have the'testa coincide with scheduled or unscheduled shutdown periods, The penetration and air purge piping leakage teat frequency, along with the containment leak rate tests, is adequate to allow detection of leakage trends. Whenever a bolted double-gaeketed penetration ia broken and remade, the space between the gaskets is pressurized to determine that the seals are performing properly. It is expected that the ma)ority of the leakage from valves, penetrations and seals would be into the reactor building. However, it is possible that leakage into other parts of the facility could occur.

Such leakage paths that may affect significantly the consequences of accidents are to be minimized, The primary containment ie normally slightly pressurized during period of

,reactor operation. Nitrogen used for inerting could leak out of the containment but air could not leak in to increase oxygen concentration. Once the containment is filled with nitrogen to the required concentration, determining the oxygen concentxation twice a week serves as an added assurance that the oxygen concentration will not exceed 4 percent, 3;7.3/3.7,C tandb ae T tment 8 tern a e onde ontai The secondaxy containment ia designed to minimize any ground level release of radioactive materials which might result from a serious accident. The reactor building provides secondary containment during xeactor operation, when the drywell is sealed and in service; the reactor building provides primary containment, if requixed, when the reactor is shutdown and the drywell is open. Because the secondary containment is an integral part of the complete containment system, secondary containment is required at all times that primary containment is required as well as during refueling.

The standby gas treatment system is designed to filter and exhaust the reactor building atmosphexe to the stack during secondary containment isolation conditions, All three standby gaa treatment system fans are designed to automatically start upon containment isolation and to maintain the reactor building pressure to the design negative pxesaure so that all leakage should be in-leakage.

High efficiency particulate air (HEPA) filters are installed before and after the charcoal adsorbers to minimize potential release of particulates to the envixonment and to'revent clogging of the iodine adsoxbers. The charcoal adsorbere are installed to reduce the potential release of radioiodine to the environment. The in-place test results should indicate a system leak tightness of lese than 1 percent bypass leakage for the charcoal adaoxbers and a HEPA efficiency of at least 99 percent removal of DOP particulates. The laboratory carbon sample test results should indicate a radioactive methyl iodide removal efficiency of at least 90 percent for expected accident conditions. If the efficiencies. of the HEPA filters and charcoal adsorbera are as specified, the resulting doses will be lees than the 10 CFR 100 guidelines for the accidents analyzed. Operation of the fans significantly different. from the design flow vill change the removal efficiency of the HEPA filters and charcoal adeorbera.

BFN 3.7/4.7-45 Unit 3

3.7/4.7 ~SJQ (Cont'd)

" I~

Only two of the three standbyI gae treatment systems nre needed to clean up the

~

reactor building ntmoophexe upon containment isolation. If one system is found to be inoperable, there ie no immediate threat to the containment system performance and reactor aperation or xefueling opexation may continue while xepairs are being made. If more than one train is inaperable nll fuel handling opexatfono, core nlterntiono, and activities with the potential to drain any reactor vessel containing fuel must be suspended and all reactors placed in a cold ohutdown condition, because the remafning train would provide only 50 percent of the capacity requfred to filter and exhaust the reactor building atmosphere to the stack. Suspension of these activities shall not preclude movement of a companent to a safe, conservative position, Operations that have the potential for draining the reactor vessel must be suspended as soon as practical to minimize the probability of a vessel draindown and subsequent potential for fission product. release. Draindown of a reactor vessel containing no fuel does not present the possibility for fuel damage or significant fission product release and therefore fs not a nuclear safety concern.

4.7,B/4.7,C ta C Tree ent S stem d Sec dax ai Initiating reactar building isolatfan and aperatfon of the standby gns treatment system to maintain at least a 1/4 inch of water vacuum within the secondary cantafnment provides an adequate test of the operation af the xeactor building isolation valves, leak tightnese of the reactor building and performance of the standby gao treatment system. Functiona11y testing the initiating sensors and associated trip logic demonstrates the capability for automatic actuatfon. Performing these tests prior to refueling will demonstrate secondary containment capability prior to the time the primary containment is opened far refueling. Periadic testing gives sufficient confidence of reactor building integrity and standby gne treatment system pexformance capability.

The test frequ'encies are adequate to detect equipment deterfoxation prior to significant defects, but the teats are not frequent enough to laad the filters, thuo reducing their reserve capacity too quickly. That the testing frequency is adequate to detect deterioration wao demanstrated by the tests which showed no loss of filter efficiency after two yeaxs of operation in the gggge4. shipboard environment on the US Savannah (ORHL 3726). Pxessure drop across the combined HEPA filters and charcaal ndsorbers of less than efx inches of water at the system design flow rate will indicate that the filters nnd adeorbere are not clogged by excessive amounts of foreign matter.

Heater capability, pressure drop and air distx'ibution should be determined at least once per operating cycle to show system performance capability.

The frequency of tests and sample analysis are necessary to show that the HEFA filters and charcoal adsorbere can perform as evaluated. Tests of the chaxconl adoorbero with hnlogenated hydrocarbon refrigerant shall be performed in accordance with USAEC Repoxt DP-1082. Iodine removal efficiency teote shall follow ASTM D3803. The charcoal adsorber efficiency teat procedures should allow fox the removal of one adeorber tray, emptying of one bed from the. tray, mixfng the adsorbent thoroughly and obtaining at least two samples.

BFN 3.7/4.7-46 Unit 3

g ENCLOSURE 2 DESCRIPTION AND JUSf IFICATION BROHNS FERRY NUCLEAR PLANT (BFN)

REASON fOR CHANGE BFN Units 1, 2, and 3 technical specifications (TSs), as described below, are being revised to clarify the Limiting Conditions for Operation (LCO) and associated bases pertaining to the interrelationships of primary containment, secondary containment, and the standby gas treatment systems (SGTS). This change will: (1) delete the remaining portion of temporary TS amendments 151, 147, and 122 for units 1, 2, and 3 respectively (SGTS); (2) clarify section 3.7.8.4 (SGTS) and its associated bases; (3) revise the requirements of section 3.7.C.2 (secondary containment); and (4) add a clarifying statement to section 3.7.C.4.b (SGTS and secondary containment).

DESCRIPTION AND JUSTIFICATION FOR THE PROPOSED CHANGE (1) Deletion of the rema i n i ng portion of temporary TS amendments 151, 147, and 122 for units 1, 2, and 3 respectively.

These amendments were made to allow fuel movement for the purpose of fuel reconstitution for unit 2 with only two of the three SGTS trains operable and with the Control Room Emergency Ventilation System (CREVS) inoperable. This was justified based on the age of the fuel, i.e.,

minimal gaseous fission product activity. This change was a temporary change to be in effect until just prior to fuel load. The portion cf these temporary amendments dealing with the CREVS were previously removed in amendments 156, 152, and 127 for units 1, 2, and 3 respectively. Fuel reconstitution has been completed and therefore the remainder of these amendments are being deleted. This is an administrative change to realign the BFN TS for plant operation.

(2) Clarify section 3.7.8.4 and its Associated Bases Existing LCO 3.7.B.4 reads:

"If these conditions cannot be met, the reactor shall be placed in a condition for which the standby gas treatment system is not required."

Proposed change to LCO 3.7.8.4 would read:.

"If.these conditions cannot be met:

a. Suspend all fuel handling operations, core alterations, and activities with the potential to drain any reactor vessel containing fuel.

b. Place all reactors in at least a HOT SHUTDOIN CONDITION within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in a COLD SHUTDONN CONDITION within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />."

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~ lD Page 2 of 4 Justification for proposed change I

LCO 3.7.B.4 The SGTS provides a means for minimizing the release of radioactive material by filtering and exhausting the air from any or all zones of the unit 1, 2,. and 3 reactor buildings. SGTS also maintains a negative pressure between the reactor buildings and the outside environment to preclude unfiltered leakage. Therefore, when the seven day LCO has been exceeded for one train of SGTS being inoperable or more than one train becomes inoperable, all operations which have a potential for initiating a radioactive release are suspended for all three units.

The proposed change is being made to clarify what specific actions are to be taken if the seven day LCO for one train of SGTS inoperable (LCO 3.7.8.3) cannot be met or if more than one train of the SGTS is inoperable. The current TS offers only general guidance if LCO 3.7.8.3 cannot be met and therefore creates the potential for varying interpretations by the operator as to what actions to take or what constitutes a condition where the SGTS is not required.

This change will provide specific actions. required to be taken if the LCO cannot be met, thereby, minimizing the potential for misinterpretation.

The actions required by this LCO will provide for the safe and timely cessation of activities which have a potential for an accidental release of radioactive material, and provide for an orderly shutdown of all reactors with minimum potential risk of fuel damage. This change is consistent with the General Electric (GE) Boiling Hater Reactor (BNR)

Standard TSs (NUREG 0123). The bases of TS 3.7.B are also being revised to reflect this change.

(3) Revise the Requirements of section 3.7.C.2 Existing LCO 3.7.C.2 reads:

"If reactor zone secondary containment integrity cannot be maintained the following conditions shall be met:

a. The reactor shall be made subcri tical and Specification 3.3.A shall be met.

b. The reactor shall be cooled down below 212'F and the reactor coolant system vented.

c. Fuel movement shall not be permitted in the reactor zone.

d. Primary containment integrity maintained."

Proposed Change to LCO 3.7.C.2 would read:

V "If reactor zone secondary containment integrity cannot be maintained the following conditions shall be met:

a. Suspend fuel handling operations, core alterations, and activities with the potential to drain any reactor vessel containing fuel.

b. Restore reactor zone secondary containment i ntegri ty within four hours, or place all reactors in at least a HOT SHUTDONN CONDITION within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in a COLD SHUTDOlN CONDITION within the following 24 hours."

Page 3 of 4 Justification for proposed change to LCO 3.7.C.2 l ~

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The secondary containment system is designed to minimize any ground level release of rad:oactive material which might result from a serious accident.

The reactor building provides secondary containment during reactor operation, when the drywell is sealed and in service. The reactor building provides primary containment, if required, when the reactor is shutdown and the drywell is open. Because secondary containment is an integral part of the containment system, secondary containment is required any time primary containment is required as well as during refueling operations.

LCO 3.7.C.2.a is required for activities associated with the potential for immediate fuel damage or loss of reactor vessel water inventory. New or irradiated fuel handling operations and core alterations (i.e., movement of fuel, sources, incore instruments, or reactivity controls within the reactor pressure vessel with the head removed and fuel in the vessel) have the potential to cause a fuel handling accident. This LCO provides for an orderly suspension of these activities and for movement of a component to a safe conservative position.

LCO 3.7.C.2.b allows four hours to restore reactor building secondary containment operability before initiating shutdown of operating reactors .

This allows a reasonable time to fix the problem before initiating shutdown.

The allowed time to reach a HOT SHUTDOWN CONDITION (12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />) and a COLD SHUTDOHN CONDITION (within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />) is sufficient to allow an orderly shutdown and cooldown of the reactor. A controlled evolution minimizes the potential risk for fuel damage. This change and the specific allowable time frames are consistent with the GE BNR Standard TSs.

Since-'these requirements place the reactor in a safe condition and minimize the potential for occurrence of any design basis accident which could release radioactive material to the environment, the existing requirement 3.7.C.2.d (to maintain primary containment integrity), under these conditions, is unnecessary.

TS LCO 3.3.A defines the control rod shutdown margin and is applicable at all times during the fuel cycle. Uncoupling this from secondary containment does not change the TS requirement for control rod operability under TS 3.3.A.

I A minor change to the bases is also being made to indicate that the reactor building provides primary containment, if required, when the reactor is shutdown and the drywell is open.

(4) Addition to section 3.7.C.4.b Existing LCO 3.7.C.4.b reads:

"The, standby gas treatment system suction to the refueling zone will be blocked except for a controlled leakage area sized to assure the achieving of a vacuum of a least 1/4-inch of water and not over three inches of water in all three reactor zones."

Proposed change to LCO 3.7.C.4.b would add the following to the existing LCO:

"This is only applicable if reactor zone integrity is required."

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4 Page 4 of 4 Justification for addition to section 3.7.C.4.b

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This change eliminates the requirement to block the SGTS suction to the refueling zone if reactor zone secondary containment is not required. If reactor zone secondary containment was not required, the SGTS would not be required to be operable so the action of blocking its suction would be unneeded. This clarification precludes unnecessary interpretations of operability requirements when SGTS is not required to be operable.

(5)

SUMMARY

Each of the proposed changes described above seeks to clarify the BFV l'Ss to minimize the need for interpretation and to bring them in line with GE BWR Standard TSs. Risk of design basis accidents without adequate containment or treatment. are minimized by actions required to shutdown operating reactors in an orderly manner and to suspend fuel handling activities, core alterations, and activities with the potential to drain any reactor vessel.

ENCLOSURE 3 DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATION DESCRIPTION OF PROPOSED TS AMENf'ENT The proposed amendment would change the Browns Ferry Nuclear Plant (BFN)

Technical Specifications (TS) for units 1, 2, 3 as follows: (1) delete the remaining portion of temporary TS amendments 151, 147, and 122 for units 1, 2, and 3 respectively; (2) clarify the actions to be taken in Limiting Conditions for Operations (LCOs) 3.7.B.4 and revise the bases accordingly; (3) revise the requirements of LCO 3.7.C.2; and (4) add a clarifying statement to LCO 3.7.C.4.b.

BASIS FOR PROPOSED NO SIGNIFICANT HAZARDS CONSIDERATION DETERMINATION NRC has provided standards for determining whether a signif'icant hazards consideration exists as stated in 10 CFR 50.92(c). A proposed amendment to an operating license involves no significant hazards considerations if operation of the facility in accordance with the proposed amendment would not (1) involve a significant increase in the probability or consequences of an accident previously evaluated, or (2) create the possibility of a new or different kind of accident from an accident previously evaluated, or (3) involve a significant reduction in a margin of safety.

1. The proposed amendment has n< effect on the probability of any previously analyzed accident. Change (1) above deletes the remaining portion of temporary TS amendments which were done to allow fuel reconstitution on unit 2 with only two out of three SGTS trains operable. Unit 2 fuel reconstitution is complete. Change (2) above clarifies the actions to be taken if SGTS operability requirements cannot be met so that interpretations are not required. Change (3) above revises the actions to be taken if reactor zone secondary containment is not operable to be consistent with GE BNR Standard TSs and eliminates the unnecessary requirement that primary containment be operable. Because of the plant design, primary containment cannot be maintained during refueling outages. Change (4) above adds a clarifying statement that the SGTS suction to the refueling zone does not have to be blocked if reactor zone secondary containment is not required.

The risks of fuel handling and reactivity insertion accidents are minimized since fuel movement and core alterations are excluded when secondary containment is not operable or insufficient SGTS capacity is available. Collectively, these changes provide specific actions to be taken if the conditions of LCOs canrot be met for the SGTS or secondary containment system. These systems serve to contain and filter the radioactive material released in an accident. These TS changes provided for an orderly and controlled suspension r>r activities with the potential to lead to an accident if an LCO cannot be m t. These changes do not involve a significant increase in the probability or consequences of an accident previously evaluated.

Page 2 of'

2. The proposed a; endment does not create the possibility of a new or different kind of accident from any accident previously evaluated. The changes clarify what to do when either the SGTS or secondary containment LCOs cannot be met. The resulting actions to mitigate radioactive material release are consistent with current plant practice and the GE BHR Standard TS requirements. No new modes of plant operation are introduced which could contribute to the possibility of a new or different kind of accident.

3. The proposed amendments do not involve a significant reduction in a margin of safety. The change is consistent with the existing BFN Safety Analysis. No adverse safety impact or reduction in safety margins occurs due to the proposed changes. They minimize operator interpretation and provide for an orderly shutdown of operating reactors and cessation of activii.les with the potential to release radioactive material if system LCQs cannot be met.

DETERMINATION OF BASIS FOR PROPOSEO NO SIGNIFICANT HA7AROS Because the application for amendment involves a proposed change that is encompassed by the criteria for which no significant hazards consideration exists, TVA has made a proposed determination that the application involves no significant hazards consideration.