ML20087G305: Difference between revisions
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Line 117: | Line 117: | ||
3.6/4.6 BAILit . | 3.6/4.6 BAILit . | ||
M083 3.6.A/4.6.A.(Cont'd) _ | M083 3.6.A/4.6.A.(Cont'd) _ | ||
TVA letter dated May 15, 1987, proposed to withdraw the first set of reactorsurveillancespecimensfromeachreactorvesselattheendofe[s . | TVA {{letter dated|date=May 15, 1987|text=letter dated May 15, 1987}}, proposed to withdraw the first set of reactorsurveillancespecimensfromeachreactorvesselattheendofe[s . | ||
unit's cycle which most closely approximates 8.0 EFPY of operation. The reasoning was;the development of.an integrated' surveillance program related to estimated fluence obtained from reactor vessel specimens prior 1 to 4.0 EFPY would be premature because it would be based only on extrapolations of limited dosimetry measurements taken from unit 1 during ' | unit's cycle which most closely approximates 8.0 EFPY of operation. The reasoning was;the development of.an integrated' surveillance program related to estimated fluence obtained from reactor vessel specimens prior 1 to 4.0 EFPY would be premature because it would be based only on extrapolations of limited dosimetry measurements taken from unit 1 during ' | ||
the first cycle of operation. Dosimetry measurements for 8.0 IFFY would be more credible than cycle 1 dosimetry data. NRC letter dated | the first cycle of operation. Dosimetry measurements for 8.0 IFFY would be more credible than cycle 1 dosimetry data. NRC letter dated | ||
Line 332: | Line 332: | ||
b 3.6/4.6 B&lF4 , | b 3.6/4.6 B&lF4 , | ||
JAN08 Igg-3.6.A/4.6.A (Cont'd) ; | JAN08 Igg-3.6.A/4.6.A (Cont'd) ; | ||
TVA letter dated May 15, 1987, proposed to withdraw the first set of reactor surveillance specimens from each reactor vessel at the end of escu . | TVA {{letter dated|date=May 15, 1987|text=letter dated May 15, 1987}}, proposed to withdraw the first set of reactor surveillance specimens from each reactor vessel at the end of escu . | ||
( | ( | ||
unit's cycle which most closely approximates 8.0 EFPY of operation. The ' | unit's cycle which most closely approximates 8.0 EFPY of operation. The ' | ||
Line 405: | Line 405: | ||
3.6.A/4.6.A (Cont'd) | 3.6.A/4.6.A (Cont'd) | ||
TVA letter dated May 15,-1987, proposen to withdraw.the first set'of I reactor surveillance specimens fram each reactor vessel at the end of each unit's cycle which most closely approximates 8.0 EFPY of operation. The reasoning was the. development of.an integrated surveillance program related to' estimated fluence obtained fron' reactor vessel specimens prior to 8.0 EFPY would be premature because it would be based only on. | TVA letter dated May 15,-1987, proposen to withdraw.the first set'of I reactor surveillance specimens fram each reactor vessel at the end of each unit's cycle which most closely approximates 8.0 EFPY of operation. The reasoning was the. development of.an integrated surveillance program related to' estimated fluence obtained fron' reactor vessel specimens prior to 8.0 EFPY would be premature because it would be based only on. | ||
extrapolations of limited dosimetry measurements taken from unit 1 during the first cycle of operation. Dosimetry measurements for 8.0 EFPY would i be more credible than cycle 1 dosimetry data. NRC letter dated December 2, 1988, stated that BFN could withdraw the first reactor vessel specimen from each reactor vessel at the end of each unit's cycle of operation that most closely approximates 8.0 EFPY of operation. After withdrawal of each unit's first sample, the remaining specimens will be : | extrapolations of limited dosimetry measurements taken from unit 1 during the first cycle of operation. Dosimetry measurements for 8.0 EFPY would i be more credible than cycle 1 dosimetry data. NRC {{letter dated|date=December 2, 1988|text=letter dated December 2, 1988}}, stated that BFN could withdraw the first reactor vessel specimen from each reactor vessel at the end of each unit's cycle of operation that most closely approximates 8.0 EFPY of operation. After withdrawal of each unit's first sample, the remaining specimens will be : | ||
withdrawn every 6.0 EFPY thereafter. | withdrawn every 6.0 EFPY thereafter. | ||
As described in paragraph 4.2.5 of the Safety Analysis Report, detailed stress analyses have been made on the reactor vessel for both steady-state and transient conditions with respect to material fatigue. .The results of these analyses are compared to allowable stress limits. Requiring the coolant temperature in an idle recirculation loop to be within 50*F of the . i operating loop temperature before a recirculation pump is started assures. | As described in paragraph 4.2.5 of the Safety Analysis Report, detailed stress analyses have been made on the reactor vessel for both steady-state and transient conditions with respect to material fatigue. .The results of these analyses are compared to allowable stress limits. Requiring the coolant temperature in an idle recirculation loop to be within 50*F of the . i operating loop temperature before a recirculation pump is started assures. | ||
Line 481: | Line 481: | ||
3.6/4.6 R&&E1 3.6.A/4.6.A (Cont'd). | 3.6/4.6 R&&E1 3.6.A/4.6.A (Cont'd). | ||
TVA letter dated May 15, 1987, proposed to withdraw the first set of- ' | TVA {{letter dated|date=May 15, 1987|text=letter dated May 15, 1987}}, proposed to withdraw the first set of- ' | ||
reactor surveillance specimens from each reactor vessel at the end of each unit's cycle which most closely approximates 8.0 EFPY of operation. The reasoning was the development of an integrated surveillance program related to estimated fluence at this time would be premature because it would be~ | reactor surveillance specimens from each reactor vessel at the end of each unit's cycle which most closely approximates 8.0 EFPY of operation. The reasoning was the development of an integrated surveillance program related to estimated fluence at this time would be premature because it would be~ | ||
based only on extrapolations of limited dosimetry measurements taken from unit 1 during the first cycle. Dosimetry measurements for 8.0 EFPY would be more credible than cycle 1 dosimetry data. NRC letter dated = | based only on extrapolations of limited dosimetry measurements taken from unit 1 during the first cycle. Dosimetry measurements for 8.0 EFPY would be more credible than cycle 1 dosimetry data. NRC letter dated = | ||
Line 535: | Line 535: | ||
p 3.6/4.6 BASES 3.6.A/4.6.A (Cont'd) | p 3.6/4.6 BASES 3.6.A/4.6.A (Cont'd) | ||
TVA letter dated May 15, 1987, proposed to withdraw the first' set of reactor surveillmace specimens from each reactor vessel at the end of each unit's cycle which most closely approximates 8.0 EFPY of operation. The | TVA {{letter dated|date=May 15, 1987|text=letter dated May 15, 1987}}, proposed to withdraw the first' set of reactor surveillmace specimens from each reactor vessel at the end of each unit's cycle which most closely approximates 8.0 EFPY of operation. The | ||
. reasoning was the-development of an integrated surveillance program related to estimated fluence at this time would be premature because it would be based only on extrapolations of limited dosimetry measurements taken frca unit.1 during the first cycle. Dosimetry measurements for 8.0 EFPY would be more credible than cycle 1 dosimetry data. NRC letter dated December 2, 1988, agreed and stated that BFN could withdraw the first specimen from each reactor vessel at the end of each unit's cycle of operation most closely approximates 8.0 EFPY of operation. After withdrawal of each unit's_first sample, the remaining specimens will be withdrawn every 6.0 ETPY thereafter. | . reasoning was the-development of an integrated surveillance program related to estimated fluence at this time would be premature because it would be based only on extrapolations of limited dosimetry measurements taken frca unit.1 during the first cycle. Dosimetry measurements for 8.0 EFPY would be more credible than cycle 1 dosimetry data. NRC {{letter dated|date=December 2, 1988|text=letter dated December 2, 1988}}, agreed and stated that BFN could withdraw the first specimen from each reactor vessel at the end of each unit's cycle of operation most closely approximates 8.0 EFPY of operation. After withdrawal of each unit's_first sample, the remaining specimens will be withdrawn every 6.0 ETPY thereafter. | ||
As described in paragraph 4.2.5 of the Safety Analysis Report, detailed stress analyses have been made on the reactor vessel for both steady-state and transient conditions with respect to material fatigue. The results of these analyses are compared to allowable stress limits. Requiring the coolant. temperature in an idle recirculation loop to be within 50*F of the operating loop temperature before a recirculation pump is started assures that the changes in coolant temperature at the reactor vessel nozzles and bottom head region are acceptable. | As described in paragraph 4.2.5 of the Safety Analysis Report, detailed stress analyses have been made on the reactor vessel for both steady-state and transient conditions with respect to material fatigue. The results of these analyses are compared to allowable stress limits. Requiring the coolant. temperature in an idle recirculation loop to be within 50*F of the operating loop temperature before a recirculation pump is started assures that the changes in coolant temperature at the reactor vessel nozzles and bottom head region are acceptable. | ||
The coolant in the bottom of the vessel is at a lower temperature than that in the upper regions of the vessel when there is no recirculation flow. | The coolant in the bottom of the vessel is at a lower temperature than that in the upper regions of the vessel when there is no recirculation flow. |
Latest revision as of 14:36, 25 September 2022
ML20087G305 | |
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Site: | Browns Ferry ![]() |
Issue date: | 03/31/1995 |
From: | TENNESSEE VALLEY AUTHORITY |
To: | |
Shared Package | |
ML20087G302 | List: |
References | |
NUDOCS 9504040132 | |
Download: ML20087G305 (25) | |
Text
- _.
ENCLOSURE 2 TENNESSEE VALLEY AUTHORITY BROWN 8 FERRY NUCLEAR PLANT (BFN)
UNITS 1, 2, AND 3 PROPOSED TECHNICAL 8PECIFICATION (TS) CHANGE TS-349 NARKED PAGES I. AFFECTED PAGE LIST Unit 1 Unit 2 Unit 3 3.6/4.6-3 3.6/4.6-3 3.6/4.6-3 3.6/4.6-24 3.6/4.6-24 3.6/4.6 3.6/4.6-27 3.6/4.6-27 3.6/4.6-27 3.6/4.6-28 II. MARKED PAGES ,
See attached.
l l
l i
i
~ 950404d132 950331 PDR ADOCK 05000259 P PDR
7 3.6/4.6 PRIMARY SYSTEM BOUNDARY , M08N LIMITING CONDITIONS FOR OPERATION SURVEI m WCE REOUIiiEmn15 3.6.A. Thermal and Pressurization 4.6.A. Thermal and Pressurization himitations Limitations
- 4. The beltline region of 4. DELETED -
reactor vessel temperatures during inservice hydrostatic or leak testing shall be at or above the temperatures shown on curve #1 of Figure i
3.6-1. The applicability of !
this curve to these tests is extended to nonnuclear heatup and ambient loss cooldown associated with these tests only if the heatup and cooldown rates do not exceed 15'T per hour.
S. The reactor vessel head 5. . When the reactor vessel head bolting studs may be partially bolting studs are. tensioned sensioned (four sequences of and the reactor is in a cold the seating pass) provided condition, the reactor vessel the studs and flange materials shell temperature immediately are above 70*F. Before below the head flange shall loading the flanges any more, be permanently recorded.
the vessel flange and head must be greater than 80*F , and must remain above 80*F while under full tension.
l e
BFN 3.6/4.6-3 XRENDMENT N0.190 Unit 1
(-
D
,lf , a. aC E WL 3AN 0 81993 l
1 2 3 Sum 3.6.-1 ,
1200 n ,,,,,,, , (BFN Unit 1)
'l l IEIIIE N .
1 I IE1iif H i i 15 i i is a Curve No.1 l l l! l l l! / Minimum temperosure for l l ll l l l / m tats su* =
! !! !!! f m,*ed by sman xi.
1000 ,,,a iin a Minimum temperature of llll lll / I11 @*Fis required for test pressure of 1,100
- lllj j l8
/ psig.
a i i i.
f I I if iE J '
X l I !E i5 .F
/ lll lj f --
Curve No. 2 800 , ,,, , , , Minimum tempesture for g ll! !T mechanic ihe tupor
, ! 7t" #! maidown **owino
-D s r i ir 'E ' si
- r tui nuclear shutdown.
E #
2r a f
1 is z
Gg / !j El Curve No. 3
$[ g f ff ji j'y Minimum temperature for core operation (cihty) g- '
s is rla
- / I l!I includes additional margin
~ .
L / j lj,f required for 10CFR50,
@ \ j r T yy Appendix G, Par. IV.A.3
"' "h'ch b* *** *"'*" *
! b 400 g , El July 26,1983. !
m f!
... . .i1i Noios i flll These curvn include .
/ lll sufficient marein to '
200 ,
f, j 'l' provide pini si se i against feedwater nozzle ,
/ // l degradation. The curves allow for shifts in RTNOT j Pf lf l of the Reactor ves'el.
sA ' IL~ -BOLT UP TEMPERATURE.__
iiiii!ii iiiiiii bettiine materials, in ,
l giiisiii accordance with Reg.
t 0 Guh 1.M k. 2, to :
0 100 200 300 400 compensate for radiation MINIMUM TEMPERATURE embrittlement for 12 EFPY.
l (*F)
Figure 3.6-1 l
BFN 3.6/4.6-24 AMENDMENT NO. I g d Unit 1 l
F
.l' Figure 3.8.1 Curve No.1
" l l l MinimumPus for BROWNS FERRY , preseW e M su dtes UNIT 1 W
- Minimumtemperature of 1 2 2 191* F le equired for
'" f T /
testpreneurs of1,100 peig.
J Curve No,2.
'2" j Minimumtempensure for f
E / medianicalW or d / cocidam8osowing
/
5*
g j nucioer shutdowrt d / Curve No.3 Minimumtemperature for
- em - -
r
/ com opendon(cenicolaw includes addalonelmargin h j required for10CFR50, d Appendk G. Par. N.A.3 8 >
' which became afledive 5 soo I July 26,1983.
h 3
f s= 400
/ / These curvesinclude sulncient maggin to h m e.io ..
g, '
againetteedweenr nonie 200
> // cravai. .a: AmsvAue ronia strv ororsun "
dogadation. The ou_rves h ior m in E g -
of the Reaclorvesset nor.w, - hellNne mensdais, in e accordance witiReg.
m o 4o0 soo Guide 1.99 Rev.2 to too zoo soo-o g___,_'W 6 MINIMUM REACTOR YESSEL METAL TEMPERATUAE (*F) embrtilementfor12 Em
\
l
\
Figure 3.6-1 l
BFN 3.6/4.6-24 Unit 1
'-----g - _
.g .
3.6/4.6 BAILit .
M083 3.6.A/4.6.A.(Cont'd) _
TVA letter dated May 15, 1987, proposed to withdraw the first set of reactorsurveillancespecimensfromeachreactorvesselattheendofe[s .
unit's cycle which most closely approximates 8.0 EFPY of operation. The reasoning was;the development of.an integrated' surveillance program related to estimated fluence obtained from reactor vessel specimens prior 1 to 4.0 EFPY would be premature because it would be based only on extrapolations of limited dosimetry measurements taken from unit 1 during '
the first cycle of operation. Dosimetry measurements for 8.0 IFFY would be more credible than cycle 1 dosimetry data. NRC letter dated
- December 2, 1988-, stated that BFN could withdraw the first reactor vessel specimen from each reactor vessel at_the end of each unit's cycle of operation that most closely approximates'8.0 EFPY of operation. After withdrawal of each unit's first sample, the remaining specimens will'be withdrawn every 6.0 EFPY thereafter.
As described in paragraph 4.2.5 of the Safety Analysis Report, detailed ~
stress analyses have been made on the reactor vessel-for both steady-state and transient conditions with respect to material fatigue. The results of.
these analysea are compared to allowable stress limits. Requiring the coolant temperature in an idle recirculation loop to be within 50*F of the operating loop temperature before a recirculation pump is started assures '
that the changes in coolant temperature at the reactor vessel nozzles and-bottom head region are acceptable.
The coolant in the bottom of the vessel is at a lower temperature than
~
that in the upper regions of the vessel when there is no recirculation.
flow. This colder water is forced up when recirculation pumps are started. This will not result in stresses which exceed ASME Boiler ana Pressure Vessel Code,Section III limits when the temperature differential is not greater than 145'F.
The requirements for full tension boltup of the reactor vessel closure are.
based on the NDT temperature plus 60'F. This is derived from the requirements of the ASME code to which the vessel was built. The EDY~
temperature of the closure flanges, adjacent head, and shall material.is a maximum of and a maximum of 10*F for the stud terial.. Therefore, the mini temperature for full tension boltup is plus 60*F for a :
20*F 2o'F BFN 3.6/4.6-27 Unit 1 4
'e e e w-,-,ww- , -,- - , - , . - . .
- ,'
- 3.6/4.6 BL1Li
- 3.6.A/4.6.A (Cont ) M2$g total of ,34087. The partial boltup is restricted to.the full loading of-eight studa at 70*F, which is stud NDT temperature (10*F) plus 60' neutron radiation fluence at the closure flanges is well below 101 {.nyt The1 l 1 Mey; therefore, radiation effects will be minor and will not influence
- this temperature.
3.6.B/4.6.B Coolant Chemistry Materials in the primary system are primarily 304_ stainless steel and the Zircaloy cladding. The reactor water chemistry limits are established to prevent damage to these materials. Limits are placed on conductivity and 4
chloride concentrations. Conductivity is limited because it is !
continuously. measured and gives an indication of abnormal conditions and the presence of unusual materials in the coolant. Chloride limits are :
specified to prevent stress corrosion cracking of stainless steel.
Zircaloy does not exhibit similar stress corrosion failures. However, i there are some operating conditions under which the dissolved oxygen content of the reactor coolant water could be higher than .2 .3 pga, such as reactor STARTUP and Hot Standby. During these periods, the most ;
restrictive limits for conductivity and chlorides have been established. I When steaming rates exceed 100,000 lb/hr,-boiling deserates the reactor l water. This reduces dissolved oxygen concentration and assures minimal _ ,
chloride-oxygen content, which together tend to induce stress corrosion !
cracking. '
l When conductivity is in its normal range, pH and chloride and other impurities affecting conductivity must also be within their normal range. I When conductivity becomes abnormal, then chloride measurements are made to- i determine whether or not they are also out of their normal operating .
values. This would not necessarily be the case. Conductivity could be high due to the presence of a neutral salt which would not have an effect on pH or chloride. In such a case, high conductivity alone is not a cause for shutdown. In some types of water-cooled reactors, conductivities are in fact high due to purposeful addition of additives. In the case of BWRs, however, where no additives are used as~ where near neutral pH is maintained, conductivity provides a very good measure of the quality of the reactor water. Significant changes therein provide the operator with a warning mechanism so he can investigate and remedy the condition causing the change before limiting conditions, with respect to variables affecting-the boundaries of the reactor coolant, are exceeded. Methods available to the operator for correcting the off-standard condition include operation of the reactor cleanup system, reducing the input of impurities and placing the reactor in the Cold Shutdown condition. The major benefit of Cold Shutdown is to reduce the temperature dependent corrosion rates and provide time for the cleanup system to reestablish the purity of the ;
The conductivity of the reactor coolant is continuously monitored when ;
there is fuel in the reactor vessel. Once a week the continuous monitor '
is checked with an in-line flow cell and is considered adequate to assure accurate readings of the monitors. If conductivity is within its j BFN 3.6/4.6-24 Unit i AMENDMENT NO. 2 0 8 l
- 1 _m.. . . . . . . . . . .. . ,m .s r
3.6/4.6' PRIMARY SYSTEM POUNDAR' . M08m LIMITING CONDITIONS FOR OPERATION SURVEIT t AMCE REQUIrr.rmn15 3.6.A. Thermal and Pressurization 4.6.A. Thermal and Pressurization Limitations (Cont'd) Limitations (Cont'd)
- 4. The beltline region of 4. DELETED reactor vessel temperatures during inservice hydrostatic or leak testing shall be at or above the temperatures shown on curve #1 of Figure 3.6-1. The applicability of this curve to these tests-is extended to nonnuclear heatup and ambient loss cooldown associated with these tests only if the heatup and cooldown rates do not exceed 15'T per ,
hour.
- 5. The reactor vessel head 5. When the reactor vessel head )
bolting studs may be partially -bolting studs are tensioned l tensioned (four sequences of and the reactor is in a cold j the seating pass) provided condition, the reactor vessel ,
the studs and flange materials shell temperature immediate13 !
are above 70*F. Before below the head flange-shall :
loading the flanges any more, -be permanently recorded. !
the vessel flange and head l fla e must be greater than .l 82*F , and must remain above !
82*F1 while under full tension. l i
i i
I l
f BFN 3.6/4.6-3 AMENDMENT N0. 2 05 Unit 2
(
gcc wY 4 GC lM Figure 3.6.-1 1 2 3 1200 , , ,, , (BFN Units 2 and 3) is > r E lE E I ia s Curve No.1 l ll / Minimum temperature for l
j E
f E I pressure tests such as required by Section XI.
1000 f I [ Minimum temperature of f j f 178@'Fis required for
,8 r
l s/
I; test pressure of 1,100 psig, e tEi 1
& Ed
, 7 , % f[ Curve No. 2 x 800 , f ,f ,e ,E 6 Minimum temperature for
$ / [ sN ! mechanical heatup or
[ f [ $al cooldown follong nuclear shutdown.
h / j! jy 2
b@ ' ""*"
600 ' ' Minimum temperature for
@{w >
l'f ll m- a w a core operation (criticality) l !! p I
8 f includes additional margin cc i'
/ ; f required for 10CFR50,
@ -gA f f__-fjl nr i Appendix G, Par. IV.A.3 which became effective g -i i
g
- f July 26,1983.
cc
=
I Notes j
gly These curves include r , ,
.j f J l sufficient margin to 200 fj ,j i provide protection s i is against feedwater nozzle
- ' degradation. The curves j / /
allow for shifts in RTNOT f f f of the Reactorvessel
/ s/- JU - -BOLT UP TEMPERATURE---
ii!iii iiiiiiiiii beltiine materials, in sii y'iisiiii i
- ' ' ' ' ' ' ' ' '''''''' accordance with Reg.
0 ,
0 100 200 300 400 compensate for radiation MINIMUM TEMPERATURE embrittlementfor12 EFPY.
(*F)
Figure 3.6-1 XMD DMENT NO. 2 0 5 BFN 3.6/4.6-24 Unit 2
.J6 Figure 3.8.1 Curve No.1 1em Minimum tempesture for BROWNS FERRY _
required by Secdon XI.
UNIT 2 h of i2 s 178* F is required for 1'#
test pressure of 1,100 j
psig.
J Curve No. 2 9 12M Minimum terriporature for fg j
! mechanicalheetup or cooldown following f / --
nuclear shutdown.
g 1000 a
- Curve No. 3 I Minimumtemporesure for l cose opoetion (criticality) a soo includes additionalmargin h*
required for 10CFR50, '
5 soo
[ '
Appendk G. Par. IV.A.3 which became effective July 26,1983.
f Notes U These curves include 5! 4oo N@#
in rno __ g%
[ againstfeedwater nozzle ,
zoo I degradation. The curves '
allow for shifts in RT m,e, canvasi. .a ansnuoromuarrrororen** of the Reactorvesset .
_ n.e ,
est w s. in o
f/ e. m m .
accordance with Reg.
300 400 soo eM Guide 1.99 Rev. 2, to ,
o too zoo Compensete for radiennri umIMUM REACTOR YESSEL METAL TEMPERATURE PM embrittlementfor12 EFPY.
Figure 3.6-1 l i
l BFN 3.6/4.6-24 Unit 2 )
.. . . . - . . ~ . - - - -. _- ._. - - .- ~_.
3.6/4.6 BASES 3.6.A/4.6.A (Cont'd) 3AN 0 81933 -
TVA letter. dated May 15, 1987, proposed to withdraw the first set of reactor surveillance specimens from each reactor vessel at the a unit's cycle which most closely approximates 8.0 EFPY of operation. The -
reasoning was the development of an integrated surveillance program related to estimated fluence at this time would be premature because it'would.be based only on extrapolations of limited dosimetry measurements taken from i unit 1 during the first cycle. Dosimetry measurements for 8.0 EFPY would )
be more credible than cycle 1 dosimetry data. NRC. letter dated ;
December 2, 1988, agreed and stated that BFN could withdraw the first' '
specimen from each reactor vessel at the end of each unit's cycle of.
operation most closely approximates 8.0 EFPY of operation. After-withdrawal of each unit's first sample, the remaining specimens will be withdrawn every 6.0 EFPY thereafter. J,
-As described in paragraph 4.2.5 of the Safety Analysis Re' port,' detailed .
stress analyses have been made on the reactor vessel for both steady-state.
and transient conditions with respect to material fatigue. The results of these analyses are compared to allowable stress limits. Requiring the coolant temperature in an idle recirculation loop to be within 50*F of the operating loop temperature before a recirculation pump is started assures.
that the changes in coolant temperature at the reactor vessel nossles and bottom head region are acceptable.
- The coolant in the bottom of the vessel is at a lower temperature than that in the upper regions of the vessel when there is no recirculation flow.
This colder water is forced up when recirculation pumps are started. This will not result in stresses which exceed ASME Boiler and Pressure Vessel.
Code,Section III limits when the temperature differential is not greatet than 145'F.
The requitaments for full tension boltup of the reactor vessel closure are based on the NDT temperature plus 60*F. This is derived.from the requirements of the ASME code to which the vessel was built. The NDT temperature o the closure flanges, adjacent head, and shell material.is a maximum of and a maximum of.10'F for the stud material. Therefore, the minimum t erature for full tension boltup is plus 60'F for a total of M The partial boltup is restricted to the full loading of 82*F 22 *F.
22*F a
9 BFN 3.6/4.6-17 Unit 2 AMENDMNr NO. 2 05
3.6/4.6 PRIMARY SYSTEM BOUNDARI JAN 0 81993 LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REOUIREMENTS 3.6.A. Thermal and Pressurization 4.6.A. Thermal and Pressurization Limitations Limitations
- 4. The beltline region of 4. DELETED reactor vessel temperatures during inservice hydrostatic or leak testing shall be at or above the temperatures shown on curve #1 of Figure . ;
3.6-1. The applicability of this curve to these tests is extended to nonnuclear heatup and sabient loss cooldown associated with these tests only if the heatup and cooldown rates do not exceed 15'F per hour.
- 5. The reactor vessel head 5. Enen the-reactor vessel head bolting studs may be partially bolting studs are. tensioned tensioned (four sequences of and the reactor is in a Cold the seating pass) provided Condition, the reactor vessel the studs and flange materials shell temperature immediately '
are above 70*F. Before below the head flange shall loading the flanges any more, be permanently recorded.
the vessel flange and head e must be greater than 70*F , and must remain above '
70*F' while under full tension.
e t
1 Y
9 BFN 3.6/4.6-3 AMENDMENT NG. I 62
( Unit 3
& w;// x b <b $ ""
JAN 0 81993 Figure 3.6.-1 1 2 3 1200 ,, ____7 ,, , , (BFN Units 2 and 3) l I II I #
!X IE I lj jj f Curve No.1
_ar is a Minimum temperature for i j j J
/ pressure tests such as 8 E required by Section XI.
1000 f j/ Minimum temperature of f j, #
187@ *Fis required for f
r f test pressure of 1,100 psig.
fj g a r s El f l Curve No. 2
[
0
!f j j Minimum temperature for o me- 1 x r a mechanical heatup or
/ f )( "
l cooldown following h f f j nuclear shutdown.
6 #' Curve No. 3 M- @ 600
'/
F
/ ll Minimum temperature for core operation (criticality)
[ __y s I includes additional margin A' [ jj f required for 10CFR50, f '/ J Appendix G Par. IV.A.3 which became effective o 400 g,
, ,f' .,
,j g i i s y X July 26,1983.
cc j '-_--l sEs Notes
, ff __ _js i s s These curves include
/ ,p__f , ,
sufficient margin to 200 provide protection fi f ' , j ,
I E !E ' against feedwater noZZie r / / degradation. The curves
/ /, f allow for shifts in RTNDT of the Reactorvessel
/ dd A- -BOLT UP TEMPERATURE--
ii riiisiiii ii iiiiiiiiiiiiiiii beltline materials, in 0
- ' ' 0''' ''''''''''' accordance with Reg.
Guide 1.99 Rev. 2, to 0 100 200 300 40 compensate for radiation MINIMUM TEMPERATURE embrittlement for 12 EFPY.
(*F)
Figure 3.6-1 BFN 3.6/4.6-24 162 Unit 3 I
I
. ~. . -- -
Floure 3.6.1 Curve Na.1
'" Minimum tempentwo for preneurs tests such an.
BROWNS FERRY gg g g g, a 2 3 UNIT 3 Minitrusn W of 1*
f 189'F is required for test pressure of 1,100 Pei9.
Curve No.2
{1200 Minimum temperature for
, f --
s ,
cocidown bBowing E / nucieershutdowrt g 1000 a
Curve No. 3 i
M .co / - - f.
core 0 ,or rr -
includes adelonelinargin h required br10CFR50, g Appendk G. Par. IV.A.3 5 ,,, I which became eNedive July 26,1983.
f n"
400
~
j _
These curves include suNicient margin to .
zoo ,
2
[ againstfoodwater nozzle degradamon. The curves allow for chilte in RTg' evaves i. .. ans viuo rom u stev or oesunoa of the Reactorvessel o
[/ boldine metsdais, in accordance whh Reg.
o 1oo 200 soo 40o soo soo Guide 1.99 Rev. 2, to .
MonMUM REACTOR VESSEL METAL TIMERATURE (*F) ~ componeels for radisilon
( ,, , embrittlementfor12 EFPY.
l Figure 3.6-1 l
l BFN 3.6/4.6-24 Unit 3 l
- - - ~ __ - - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ , , . _ . , _ _ _ _ _ _ _ _ _ _ _ _ , . _ _ _ _ _ _ _ . _ , _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
. . _ . ~ .- .- -_ -~ -- .- _. .- - .
b 3.6/4.6 B&lF4 ,
JAN08 Igg-3.6.A/4.6.A (Cont'd) ;
TVA letter dated May 15, 1987, proposed to withdraw the first set of reactor surveillance specimens from each reactor vessel at the end of escu .
(
unit's cycle which most closely approximates 8.0 EFPY of operation. The '
reasoning was the development of an integrated surveillance program related to estimated fluence at this time would be premature because it would be based only on extrapolations of limited dosimetry measurements taken from unit I during the first cycle. Dosimetry measurements for 8.0 EFPY would-be more credible than cycle 1 dosimetry data. NRC latter dated ,
December 2, 1988, agreed and stated that BFN could withdraw the first specimen from each reactor vessel at the end of each unit's cycle of ,
operation most closely approximates 8.0 IFPY of operation.. After .
withdrawal of each unit's first sample, the remaining specimens will be withdrawn every 6.0 EFPY thereafter.
As described in paragraph 4.2.5 of the Safety Analysis Report, detailed stress analyses have been made on the reactor vessel for both steady-state.
and transient conditions with respect to material fatigue. The results of these analyses are compared to allowable stress limits. Requiring the-coolant temperature in an idle recirculation loop to be within 50'F of the operating loop temperature before a recirculation pump is started assures.
that the changes in coolant temperature at the reactor vessel nozzles and bottom head region are acceptable.
The coolant in the bottom of the vessel is at a lower temperature than that in the upper regions of the vessel when there is no recirculation flow..
This colder water is forced up when recirculation pusps are started. This will not result in stresses which exceed ASME Boiler and Pressure Vessell Code,Section III limits when the temperature differential is not greater. .
than 145'F. '
The requirements for full tension boltup of the reactor vessel closure are based on the NDT temperature plus 60*F. This is derived from the requirements of the ASME code to which the vessel was built. The NDT temperature of the closure flanges, adjacent head, and shell material is a j maximum of and a maximum of 10*F for the stud material. Therefore.
the minimum tem erature for full tension boltup is @ plus 60*F for a total of @ The partial boltup is restricted to the full loading of 7o*F <
j 10 F lO* F
)
BFN 3.6/4.6-27 AMSDMW M 16i Unit 3
-) ;
ENCLOSURE 3 TENNE 8SEE VALLEY AUTHORITY BROWM8 FERRY NUCLEAR PLANT (BFN) ,
UNIT 8 1, 2 AND 3 f l
PROPOSED TECHNICAL 8PECIFICATION (TS) CHANGE T8-349 l REVISED PAGES ]
l I. AFFECTED PAGE LIST Unit 1 Unit 2 Unit 3 3.6/4.6-3 3.6/4.6-3 3.6/4.6-3 3.6/4.6-24 3.6/4.6-24 3.6/4.6-24 3.6/4.6-27 3.6/4.6-27 3.6/4.6-27 3.6/4.6-28 II. REVISED PAGE8 See attached.
I I
3.6/4.6 PRIMARY SYSTEM BOUNDARY M NS FOR OPERATION SURVEIf.f.ANCE REOUIREMENTS
' 3.6.A. Thermal and Pressurizati23 4.6.A. Thermal ==A Pressurization Limitations Limitations
- 4. The beltline region of 4. DELETED reactor vessel temperatures during inservice hydrostatic or leak testing shall be at or above the temperatures shown on curve #1 of Figure 3.6-1. The applicability of this curve to these tests is' extended to nonnuclear heatup and ambient loss cooldown associated with these tests only if the heatup and cooldown rates do not exceed 15'F per hour.
- 5. The reactor vessel head 5. When the reactor vessel head bolting studs may be partially bolting studs are tensioned tensioned (four sequences of and the reactor is in a cold the seating pass) provided condition, the reactor vessel the studs and flange materials shell temperature immediately are above 70*F. Before below the head flange shall loading the flanges any more, be permanently recorded.
the vessel flange and head flange must be greater than 80*F, and must remain above 80*F while under full tension.
BFN 3.6/4.6-3 Unit 1
l
~
, Figure 3.6A l
Curve No.1 Mhimumtempereksefor l
'" l l l BROWNS FERRY preSeineM oulst se i UNIT I W
- Minimumtemperslure of '
1 2 3 191* F le seguired for
'" f /
testpressure of1.100 peig.
Curve No. 2
} '" Minimumtemperesse for E mechanicalhoseup or - 1 d maidownseemeing E S
'* nudeer shundoen.
Curve No. 3 '
Minimumtemperature for
- core opereelon(criticality) lU
- I r includes ediglionalmergh
) requiredsoriocrRso.
g wa.eer.ivu
, , 1 m h eNective 800 7 July 26,1983.
g g 2
2 -
!- / / m , ee -
suNicientnughto !
m eno ..
Provide protection 6 <
/
r ogehstseedeuter nonie
// degradesion. The etnvee hWeh%
ceavas u.u as vauo ron n uev oeorsun "
of the Reetsorvesset souye - g beltNne meenrisis, in i
= occordanoswith Reg.
' I 0 400 soo soo Guitte 1.99 k.E to too 200 soo- '
o CompensgeeforretNodon Mm1 MUM REACTOR VESSEL METAL TEMPERATURE (*D embrittlementfor12 EPP) 1 I
Figure 3.6-1 l
BFN 3.6/4.6-24 !
Unit 1 W- *_ _ * - , _ . -. __ - r ,.
3.6/4.6 R&E31 >
3.6.A/4.6.A (Cont'd)
TVA letter dated May 15,-1987, proposen to withdraw.the first set'of I reactor surveillance specimens fram each reactor vessel at the end of each unit's cycle which most closely approximates 8.0 EFPY of operation. The reasoning was the. development of.an integrated surveillance program related to' estimated fluence obtained fron' reactor vessel specimens prior to 8.0 EFPY would be premature because it would be based only on.
extrapolations of limited dosimetry measurements taken from unit 1 during the first cycle of operation. Dosimetry measurements for 8.0 EFPY would i be more credible than cycle 1 dosimetry data. NRC letter dated December 2, 1988, stated that BFN could withdraw the first reactor vessel specimen from each reactor vessel at the end of each unit's cycle of operation that most closely approximates 8.0 EFPY of operation. After withdrawal of each unit's first sample, the remaining specimens will be :
withdrawn every 6.0 EFPY thereafter.
As described in paragraph 4.2.5 of the Safety Analysis Report, detailed stress analyses have been made on the reactor vessel for both steady-state and transient conditions with respect to material fatigue. .The results of these analyses are compared to allowable stress limits. Requiring the coolant temperature in an idle recirculation loop to be within 50*F of the . i operating loop temperature before a recirculation pump is started assures.
that the changes in coolant temperature at the reactor. vessel nozzles and ,
bottom head region are acceptable.
The coolant in the bottom of the vessel is at a lower temperature than i that in the upper regions of the vessel when there is no recirculation ,
flow. This colder water is forced up when recirculation pumps are started. This will not result in stresses which exceed ASME Boiler and <
Pressure Vessel Code,Section III limits when the temperature differential l is not greater than 145'F. i t
The requirements for full tension boltup of the reactor vessel closure are I based on the NDT temperature plus 60'F. This is derived from the l requirements of the ASME code to which the vessel was built. The NDT temperature of the closure flanges, adjacent head, and shell material is a
)1 maximum of 20'F and a maximum of 10*F for the stud material. Therefore, the minimum temperature for full tension boltup is 20'F plus 60'F for a total of 80*F. The partial boltup is restricted to the full loading of eight studs at 70'F, which is stud NDT temperature (10*F) plus 60' j neutron radiation fluence at the closure flanges is well below 10 {.nyt The1 i 1 Mev; therefore, radiation effects will be minor and will not influence this temperature.
)
BFN 3.6/4.6-27 a Unit 1 1
)
- - - . - . ... - - - _ - - . ~ _ - . -- - - _. .
3.6/4.6'B&&E1 3.6.B/4.6.B Coolant Chamistry f
Materials in the primary' system are primarily 304 stainless steel and the Zircaloy cladding. The reactor water chemistry limits are established to prevent' damage to these materials. Limits are placed on conductivity and- .
chloride' concentrations. Conductivity is limited because-it is continuously measured and gives an indication of abnormal conditions.and the presence of unusual materials in the coolant. Chloride limits are .
specified to prevent stress corrosion cracking of stainless steel.
'i Zircaloy does not exhibit similar stress corrosion failures. However,
.there are some operating conditions under which,the dissolved oxygen . .
content of the reactor coolant water could be higher than .2 .3 ppe, such :
as reactor STARTUP and Hot Standby. During these periods,'the most restrictive limits for conductivity and chlorides have been established.
When steaming rates exceed 100,000 lb/hr, boiling deserates the reactor ;
water. This reduces dissolved oxygen concentration and assures minimal i chloride-oxygen content, which together tend to induce stress corrosion t cracking.
When conductivity is in its normal range, pH and chloride and other impurities affecting conductivity must also be within their normal' range.
When conductivity becomes abnormal, then chloride measurements are made tol <
determine whether or not they are also out of their normal operating _
values. This would not necessarily be-the case. Conductivity could be high due to'the presence of a neutral salt which would not'have an effect on pH or chloride. In such a case, high conductivity alone is not a cause for shardown. ~In some types of water-cooled reactors, conductivities are 1 in fact high due to purposeful addition of additives. In the case of BWRs, however, where no additives are used' and where-near neutral pH is-maintained, conductivity provides a very good measure of the quality of the reactor water. Significant changes therein provide the operator.with ,
a warning mechanism so he can investigate and remedy the condition causing ,
i the change before limiting conditions, with respect to variables affecting-the boundaries of the reactor coolant, are exceeded. Methods available to the operator for correcting the off-standard condition include operation of the reactor cleanup system, reducing the input of impurities and placing the reactor in the Cold Shutdown condition. The major benefit of :
, ' Cold Shutdown is to reduce the temperature dependent corrosion rates and provide time for the cleanup system to reestablish the purity of the - ,
4' '
l i The conductivity of the reactor coolant is continuously monitored when l there is fuel in the reactor vessel. Once a week the continuous monitor.
is checked with an in-line flow cell and'is considered. adequate to assure
~
- accurate readings of the monitors. If conductivity is within its BFN 3.6/4.6-28 l Unit 1 1
_ , , _ ~ . _ . _ . - , _ , , , - - - , - -
,.,,-,4
F .i
- . 1 L.
3.6/4.6 PRIMARY SYSTEM BOUNDARY LIMITINC COLmITIONS FOR OPEDavION SURVETH AmCE REQUIidi. .m15 3.6.A. Thermal and Pressurization 4.6.A. Thermal and Pressurization 'j' Limitations (Cont'd) Limitations (Cont'd)
- 4. The beltline region'of '4. DELETED reactor vessel temperatures during inservice hydrostatic or leak testing shall be at p or above the temperaturesL shown on curve #1 of Figure 3.6-1. . The applicability of this curve..to these tests is-extended to nonnuclear heatup and ambient loss cooldown associated with i these tests only if the L heatup and cooldown rates do not exceed 15*F per hour.
- 5. The reactor vessel head 5. When the reactor vessel head. j bolting studs may be partially bolting stude are tensioned tensioned (four sequences of and the reactor is~in a cold the seating pass) provided condition, the reactor vessel. 1 the studs and flange materials shell temperature immediately are above 70*F. Before below the head flange shall loading the flanges any more, be permanently recorded.
the vessel flange and head l
flange must be greater than 82'F, and must remain above 82*F while under full tension.
l I
.1 1
3.6/4.6-3 BFN Unit 2
l l
j Figure 3.6.-1 :
1 Curve No.1 isoo MinkrunnW for BROWNS FERRY ~
retluired by Section XI.
UNIII of 2 3, 1400 178*F is required for test pressure of 1,100 psia.
l l Curve No. 2
{I 12" f
Minimum temperature for rnosanicalheetup or r5 g maidown follomno f '"'
R f
/ nucieershuasown. .i d / Curve No.3
[ Minimumtemperature for
- core operation (criticalitW p includes additionalmergin >
G regured for10CFR50, g j Appendir G. Par. N.A.3 g 8#
[ -
which became enedive b 1 July 26,1988.
g f
!! 4#
/ / These curvesinclude g sufficientmargin to g m raio ~ provide protection againstfeedwater nozzle degredation. The arves 2m m.m allowfor shlRs in RT T
_. m r convasi. .mma vum rom n arry ' ' ' " * " , ofthe R e w h.un. meierus, in V, accordance with Reg, soo 4o0 soo s# Guide 1.99 Rev. 2, to o too 200 wiipwi _ _ ^ forredledon MmWUM REACTOR VE5SEL METAL TEMPERATURE ('F) embritdementfor12 EFPY,
~
Figure 3.6-1 1
BFN 3.6/4.6-24 Unit'2
3.6/4.6 R&&E1 3.6.A/4.6.A (Cont'd).
TVA letter dated May 15, 1987, proposed to withdraw the first set of- '
reactor surveillance specimens from each reactor vessel at the end of each unit's cycle which most closely approximates 8.0 EFPY of operation. The reasoning was the development of an integrated surveillance program related to estimated fluence at this time would be premature because it would be~
based only on extrapolations of limited dosimetry measurements taken from unit 1 during the first cycle. Dosimetry measurements for 8.0 EFPY would be more credible than cycle 1 dosimetry data. NRC letter dated =
December 2, 1988, agreed and stated that BFN could withdraw the first L specimen from each reactor vessel at the end of each unit's cycle of I operation most closely approximates 8.0 EFPY of. operation. .After I withdrawal of each unit's first sample, the remaining specimens will be withdrawn every 6.0 ETPY thereafter.
As described in paragraph 4.2.5 of the Safety Analysis Report, detailed stress analyses have been made on the reactor vessel for both steady-state and transient conditions with respect to material. fatigue. The results of these analyses are compared to allowable stress limits. Requiring.the coolant temperature in an idle recirculation loop to be within 50*F of the operating loop temperature before a recirculation pump is started assures ,
that the changes in coolant temperature at the reactor vessel nozzles and l bottom head region are acceptable. !
)
The coolant in the bottom of the vessel is at a lower temperature than that in the upper regions of the vessel when there is no recirculation flow. -l This colder water is forced up when recirculation pumps are started. This will not result in stresses which exceed ASME Boiler and Pressure Vessel Code,Section III limits when the temperature differential is not greater than 145'F.
The requirements for full tension boltup of the reactor vessel closure are based on the NDT temperature plus 60*F. This is derived from the requirements of the ASME code to which the vessel was built. The NDT temperature of the closure flanges, adjacent head, and shell material is a-maximum of 22*F and a maximum of 10*F for the stud material. Therefore, the minimum temperature for full tension boltup is 22*F plus 60*F for a-l total of 82*F. The partial boltup is restricted to the full loading of BFN 3.6/4.6-27 Unit 2
_ m - - - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
3.6/4.6 PRIMARY SYSTEM BOUNDARY LIMITING CONDITIONS FOR OPERATION SURVEII,f.ANCE REOUIREMENTS 3.6.A. Thermal and Pressurization 4.6.A. hal and Presstirization Limitations Limitations
- 4. The beltline region of 4. DELETED reactor vessel temperatures J ,
during inservice hydrostatic or leak testing shall be at or above the temperatures shown on curve #1 of Figure 3.6-1. The applicability of this curve to these. tests is extended to nonnuclear heatup and ambient loss cooldown associated with these tests only if the heatup and cooldown rates do not exceed 15'F per hour.
- 5. The reactor vessel head 5. When the reactor vessel head bolting studs may be partially bolting studs are tensioned tensioned (four sequences of and the reactor is in a Cold the seating pass) provided Condition, the reactor vessel the studs and flange matetials shell temperature immediately are above 70*F. Before below tb2 head flange shall loading the flanges any more, be permanently recorded.
the vessel flange and head flange must be greater than 70*F, and must remain above 70*F while under full tension.
l l
s r
BFN 3.6/4.6-3 Unit 3
I i
i l
Figure 3.8.-1 -l j
Curve h_1
'" Mhimum tempemews for preneurs teste sue as ,
BROWNS FERRY g g g, UNTT3 Minimum tempemese of
, ., 3 1'00 t t 189*F is required for test pressure of 1,100 poiO. i
.{120o Cwve W Minimum temperature for 6 f mechanicalheetup or 5 f >
- oooldown fogowing
/
h ** j nuclear shutdown.
d / Curve Nc32 -
g i Minimum temperature for -
5:
M 80o
/ Core opW1ditm M includes s.dditionalmargin h required for10CFR50, ;
g Appendk G, Par. IVA3 f 5 800 l i which became ellective !
-g ,
7 July 26,1983.
g / fj l
- 400 ll ~
These curves include sufficient margin to h
provide prolmetion .
m r.o 200 ,
2
/ againstfeedwater nozzle degradatiorL Thecurvgs allow forshills in RTg cunvas u.u asvwo com u serv or ormno" of the Reactorvessel o
"",,'7'
[/ boldine meterials, in accordance with Reg. >
o too zoo soo 400 soo soo Guide 1.99 Rev. 2, to Mov MUM REACTOR VE5SEL METAL TEMPERATURE ('F) Mp:17 forindisting '
embrlitismontfor12 EFPY.-
Figure 3.6-1 ,
BFN 3.6/4.6-24 Unit 3 ,
p 3.6/4.6 BASES 3.6.A/4.6.A (Cont'd)
TVA letter dated May 15, 1987, proposed to withdraw the first' set of reactor surveillmace specimens from each reactor vessel at the end of each unit's cycle which most closely approximates 8.0 EFPY of operation. The
. reasoning was the-development of an integrated surveillance program related to estimated fluence at this time would be premature because it would be based only on extrapolations of limited dosimetry measurements taken frca unit.1 during the first cycle. Dosimetry measurements for 8.0 EFPY would be more credible than cycle 1 dosimetry data. NRC letter dated December 2, 1988, agreed and stated that BFN could withdraw the first specimen from each reactor vessel at the end of each unit's cycle of operation most closely approximates 8.0 EFPY of operation. After withdrawal of each unit's_first sample, the remaining specimens will be withdrawn every 6.0 ETPY thereafter.
As described in paragraph 4.2.5 of the Safety Analysis Report, detailed stress analyses have been made on the reactor vessel for both steady-state and transient conditions with respect to material fatigue. The results of these analyses are compared to allowable stress limits. Requiring the coolant. temperature in an idle recirculation loop to be within 50*F of the operating loop temperature before a recirculation pump is started assures that the changes in coolant temperature at the reactor vessel nozzles and bottom head region are acceptable.
The coolant in the bottom of the vessel is at a lower temperature than that in the upper regions of the vessel when there is no recirculation flow.
This colder water is forced up when recirculation pumps are started.. This will not result in stresses which exceed ASME Boiler and Pressure Vessel-Code,Section III limits when the temperature differential is not greater than 145'F.
The requirements for full tension boltup of the reactor vessel closure are based on the NDT temperature plus 60*F. This is derived from the requirements of the ASME code to which the vessel was built. The NDT temperature of the closure flanges, adjacent head, mui shell material is a maximum of 10*F and a maximum of 10*F for~the stud materiel. Therefore, the minimum temperature for full tension boltup is 10*F plus 60*F for a total of 70*F. The partial boltup is restricted to the full loading of BFN 3.6/4.6-27 Unit 3 ,
. - -. _. . - - .