ML20247R702
| ML20247R702 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 05/20/1998 |
| From: | NORTH ATLANTIC ENERGY SERVICE CORP. (NAESCO) |
| To: | |
| Shared Package | |
| ML20247R662 | List: |
| References | |
| NUDOCS 9805290202 | |
| Download: ML20247R702 (15) | |
Text
,
Section 11 Markup of the Proposed Change Please note that the attached markups reflect the currently issued revision of the Technical Specifications listed below. Pending Technical Specifications or Technical Specification changes issued subsequent to this submittal are not reflected in the enclosed markup.
The following Technical Specifications are included in the attached markup:
Technical Specification Title Page(s)
Ta ble 3.3-4 Engineered Safety Features Actuation System 3/4 3-27 Instrumentation Setpoints Table 3.3-4 Table Notations 3/4 3-29 Itases 3/4.3.2 Reactor Trip System and Engineered Safety 113/43-2 Features Actuation System Instrumentation Page 4 9905290202 990520 ADOCK 05000443.,
r.
~_
- s w e ot u E rn l U re a
~
L A
am nu V
V r e mw% d d
ft n l / n E
L B
os
%i n
a s
b a
w Sy 2 a s
A t o 6, t .
W O
- 6. e . n l /f 2,
n L
L A. A. A.
. 2gn 1 na ap i
o p
l A A. / , ni 1 p o
S A N N N >rs t e
d n Ndy> t e -
T 5 a S N .
I T p s s p O N e i t l a
i r
P I g r n g T O f nt T i T E P oan o .
re n p 8 n S
P I
T E
S %wu
- 0. o r m
i t
o t S
e 7no 4 pi. i t
R P . . . 4 rtn c .
o 2 c T I R A. A. A.
1rsa anp j e r e A. t uj e N T N N N >iis i n w N f> n O I o i I P T y y A t e t T e t e N R . . . 5 f i . f E OR 5 a s a A.
)
M U
R SO)
NRS ER(
A.
N N N A. A.
0
. S l
f f
O
- N 6.
2 R l S
d T SE l - l e S a f a u N o .
n I 3 r - - r i . . . 5 o s . o t M . f s 0 f n E A. A. A. 2 o A. .
o T Z N N N 1 e . l N 1 e .
C S vs vs
( Y oe r oe S ) bu o bu
. 4 3
- N O (
A T
1 al
.V a
f
+y a 1 al
.V a
9 3
. I T
A E
ml e
m
+ ml e
E U N C
eb e 01, eb L T A t a t 42 t a B C LW I w i I w A A AO . . . 0 o . o T TL . el e A.
el A. A. A.
S E
R U
OL TA N N N 4
1 SA el S
e N MSA el T
A E
F -
Y c c T pi m g pe n pp pp
'i g
E F
A p u o m pL r mv ui mm uu ruu mm L o
S u s e Pr PP ePP s p n nyt D w o ny w D e oa a n- nn onn oa o n E n n v il W ee ee Pee t il L o R
o e i te vn nvv vv r
t e aR wht i
E i v r aR r ii oii eii E r t i d u owrb i rr t rr e u otc N e a r tn t oDr tDD iDD v t n Li e Wj I t i d e co aL- u c- - s- - o co G a t n Ai r- rT ere f re hp Ai - n N w i r i t ewo jon f on cm ca t l tI en E d n o b ca nott nti Oti tu vey e I t r iu eLor I ob - ob iS iu e o u tt G- Ma y Mr fMr w tt edt F l M T a c_ - t u o u St ac Lie T a '
mA mltS ttT tT n mA cf I y u o aer p er sr ce o Tna N c n ) ) td evadm f ad sad im td sis U n e
a 1 2 un t et nu atn ot n tn un Wo RC M ( ( Aa SLSaP SSa LSa ai Aa L
A r g ma ot N e t n O m . . . . . uo . .
I E a b c d e AC a b T
C N
U F 7
. , 8
,bEw C g[ , w1 w y o_ - .
~ .
y..-
TABLE 3.3-4 (C'ontinued) [:y TABLE NOTATIONS f..
" Time constants utilized in the lead-lag controller for Steam Line Pressure-Low CHANNEL CALIBRATION shall ensure :!{
are T 1 > 50 seconds and T2 < 5 seconds. [.il that these time constants are adjusted to these values.
f:
- The time constant utilized in the rate-lag controller for Steam Line Pressure-CHANNEL :,
Negative Rate-High is greater than or equal to 50 seconds.
- shall ensure that this time constant is adjusted to this value.
~
ww SPEC /F/ED A ppt. EG MHEM A5 t1EAsufEO TA9P :
YAL uE 77/AN 7)+C SP6CIFI2D T2f SETA!VNf ?
GEI~feiMi IS CffATL2 !
11 WW 7&P VALUE SPEC /f)EO APNES WMN
- As HEAsudEO TMM TMf- SPEC /RfD TAlf bEM/W. j SSrfi/A/T IS LESS ,
i
\
9 4
e
6
\ .s.
INSTRUMENTATION 1
BASES 3/4.3.1 and 314.3.2 REACTOR TRIP SYSTEN and ENGINEERED SAFETY FEATURES ACTUATION SYSTEM INSTRUMENTATION (Continued) uncertainties of the instrumentation to measure the process variable and the uncertainties in calibrating the instrumentation. In Equation 2.2-1, l Z + R S s TA, the interactive effects of the errors in the rack and the sensor, and the "as measured" values of the errors are considered. Z, as specified in Table 3.3-4, in percent span, is the statistical summation of errors assumed in the analysis excluding those associated with the sensor and rack drift and the accuracy of their measurement. TA or Total Allowance is the difference, in percent span; R or Rack Error is the "as measured" deviation, in the percent span, for the affected channel from the specified Trip Setpoint. 5 or Sensor Error is either the "as measured" deviation of the sensor from its calibration point Jr the value specified in Table 3.3-4, in percent span, from the analysis assumptions. Use of Equation 2.2-1 allows for a sensor drift factor, an ~l l increased rack drift factor, and provides a threshold value for REPORTABLE EVENTS.
The methodology to derive the Trip setpoints is based upon combining all of the uncertainties in the channels. Inherent to the determination of the Trip Setpoints are the magnitudes of these channel uncertainties.. Sensor and rack instrumentation utilized in these channels are expected to be. capable of m operating within the allowances of these uncertainty magnitudes. Rack drift in
- excess of the Allowable Value exhibits the behavior that the rack has not met its allowance. Being that there is a small statistical chance that this will happen, an infrequent excessive drift is expected. Rack or sensor drift, in excess of the allowance that is more than occasional, may be indicative of more serious problems and should warrant further investigation.
The measurement of response time at the specified frequencies provides assurance that the Reactor trip and the Engineered Safety Features actuation i associated with each channel is completed within the time limit assumed in the i safety analyses. No credit was taken in the analyses for those channels with I response times indicated as not applicable. Response time may be demonstrated by any series of sequential, overlapping, or total channel test measurements provided that such tests demonstrate the total channel response time as defined.
Sensor response time verification may be demonstrated by either: (1) in place, onsite, or offsite test measurements, or (2) utilizing replacement sensors with g certified response time.
The Engineered safety Features Actuation System senses selected plant parameters and determines whether or not predetermined limits are being
~
exceeded. If they are, the signals are combined into logic matrices sensitive to combinations indicative of various accidents, events, and transients. Once the required logic combination is completed, the system sends actuation signals to those Enginaered Safety Features components whose aggregate function best serves the requirements of the condition. As an examp e, the following actions may be initiated by the Engineered Safety Features Actuation System to mitigate the consequences of a steam line break or loss-of-coolant accident: (1) Safety
.vf SEA 8R00K - UNIT 1 B 3/4 3-2 AmendmentNo.)4'
j..
- $[
At the end of the injection phase of a LOCA, the RWST will be nearly empty. Continued cooling must be provided by the ECCS to remove decay heat. The source of water for the ECCS pumps is automatically switched to the containment recirculation sumps. The low head residual heat removal (RllR) pumps and containment spray pumps draw the water from the containment recirculation sumps, the RilR pumps pump the water through the RilR heat exchange inject the water back into the RCS, and upon manual alignment supply the cooled water to the other CCS pumps. Switchover from the RWST to the containment recirculation sumps must occur before the RWST empties to prevent damage to the ECCS pumps and a loss of core cooling capability. For similar reasons, switchover must not occur before there is sufficient water in the containment sump to provide sufficient net positive suction head (NPSH) to support ECCS pump operation. Furthermore, early switchover must not occur to ensure that sufficient borated water is injected from the RWST. This ensures the reactor remains shut down in the recirculation mode. To satisfy these requirements, the RWST Level Low-Low Allowable Valueffrip Setpoint has both upper and lower limits. The lower limit ensures switchover occurs before the RWST empties to prevent ECCS pump damage while the upper limit ensures the reactor remains shut down and that there is adequate water inventory in the containment recirculation sumps to provide ECCS pump suction.
l
.s e
s SECTION III Retype of the Proposed Change Please note that the attached retype of the proposed change to the Technical Specifications reflects the currently issued version of the Technical Specifications. Pending Technical Specification changes or Technical Specification changes issued subsequent to this submittal are not reflected in the enclosed retype. The enclosed retype _ should be checked for continuity with Technical Specifications prior to issuance.
Page 5
B A
%i d e 23 n 5 W
O . . .
6.
2 gn
- e. a l
b a .
19 L
A. A. A. 1 na s w A. 21 L ap t o 11 A N N N 2rs n l N s i l S o p
A T t d N
I e n O T S a P N e g p s
T I s l E O fnt i t a S P oan r n g T re T i P E % m o 8 I
R S
P .
- 0. wu 4rtn or. n o t p
e 7
4 T . . i I 1 rsa t S 0 N R A. A. A. anp c A.. 2 O T N N N 2nis e r N 1 I j e T n w A I o T P N y E
R t e M e t U OR) f i
) R SOS . . .
5 a s .
T NR( 5 S f 8 d S ER A. A. A. f A.
e N SE N N N 0 l O N 2 u I l -
n a f i
t M -
r o-E 3 n T 5 o s o S f s 0
C Y A. A.. A.. 2 o A.
(
S Z N N N 1 e . L N 1 vs 4 N oe r 3
O ) bu o I A al f 3 . T T
(
a A .V .
E U 1 9 T E e B
L C C ml m A A N A
eb e ta t T S LW I w I E AO TL 0
el o
e
~01 R A. A. A. A.
U OL 4 el e T TA N N N 1 SA S N 42 A
E F
Y T
E F
A p c c i n i S m g pe pp pp g D m p u o r
mv mm mm o E u p L s
ui uu ruu L e Pr PP ePP s R p n ny t D w ny w E e oa a n- nn onn o oa o E n n v il W ee ee Pee t il L N o e i te vn nvv vv te -
I r
i v r aR r ii oii eii r aR w G
e t i d u owrb irr trr e u ot N a r tn toDr tDD iDD v tn Li E t a
i d e co aL u c- - s- - o co t n Ai r rT ere fre hp Ai ewo cm w i r i t jon fcn t lt d n o b ca nott nti Oti tu ca e e I t r iu eLor I ob ob iS iu v e o u tt G Ma Mr fMr w tt ed F l M T ac - t y u o u St ac Li T n I
N y u a mA o
mltS aer p er ttT sr tT ce mA o Tn c n ) ) td evadm fad sad im td si U n a e
1 2 un tetnu atn otn tn un Wo g M Aa SLSaP
( ( SSa ai LSa Aa RC L
A r ma ot N e tn O m . . . . .
uo . .
I E a b c d e AC a b T
C N
U .
F 7 8 w988^'g 5 [ a2 a4" i dggnA
=O r' .!l ll ,l
s
. TABLE 3.3-4 (Continued)
TABLE NOTATIONS
- lime constants utilized in the lead-lag controller for Steam Line Press'ure-Low are t 2 50 seconds and T s 5 seconds.
2 CHANNEL CALIBRATION shallensurethatkhesetimeconstantsareadjustedtothesevalues.
- The time constant utilized in the rate-lag controller for Steam Line i Pressure-Negative Rate-High is greater than or equal to 50 seconds.
CHANNEL CALIBRATION shall ensure that this time constant is adjusted to this value.
- Value specified applies when "as measured" 1 rip Setpoint is greater than the specified Trip Setpoint.
- Value sp cified applies when "as measured" Trip Setpoint is less than the specifi j Trip Setpoint.
1 SEAB.'t00K - UNIT 1 3/4 3-29 Amendment No.
INSTRUMENTATION BASES 3/4.3.1 and 3/4.3.2 REACTOR TRIP SYSTEM and ENGINEERED SAFETY FEATURES ACTUATION SYSTEM INSTRUMENTATION (Continued) uncertainties of the instrumentation to measure the process variable and the l uncertainties in calibrating the instrumentation. In Equation 2.2-1.
Z + R S s TA the interactive effects of the errors in the rack and the sensor, and the "as measured" values of the errors are considered. Z, as specified in Table 3.3-4. in percent span. is the statistical summation of errors assumed in the analysis excluding those associated with the sensor and rack drift and the accuracy of their measurement. TA or Total Allowance is the difference, in percent span: R or Rack Error is the "as measured" deviation. in the percent span, for the affected channel from the specified Trip Setpoint. S or Sensor Error is either the "as measured" deviation of the sensor from its calibration point or the value specified in Table 3.3-4 in percent span, from the analysis assumptions. Use of Equation 2.2-1 allows for a sensor drift factor, an increased rack drift factor, and provides a threshold value for REPORTA3LE EVENTS.
The methodology to derive the Trip Setpoints is based upon combining all of the uncertainties in the channels. Inherent to the determination of the Tri) Setpoints are the magnitudes of these channel uncertainties. Sensor and rac( instrumentation utilized in these channels are expected to be ca)able of operating within the allowances of these uncertainty magnitudes. Rac( drift in excess of the Allowable Value exhibits the behavior that the rack has not met l its allowance. Being that there is a small statistical chance that this will I happen, an infrequent excessive drift is expected. Rack or sensor drift, in I excess of the allowance that is more than occasional. may be indicative of more serious problems and should warrant further investigation.
The measurement of response time at the specified frequencies provides assurance that the Reactor trip and the Engineered Safety Features actuation associated with each channel is completed within the time limit assumed in the safety analyses. No credit was taken in the analyses for those channels with response times indicated as not applicable. Response time may be demonstrated by any series of sequential, overlapping, or total channel test measurements provided that such tests demonstrate the total channel response time as defined. Sensor response time verification may be demonstrated by either:
(1) in place, onsite, or offsite test measurements, or (2) utilizing replacement sensors with certified response time.
At the end of the injection phase of a LOCA. the RWST will be nearly empty. Continued cooling must be provided by the ECCS to remove decay heat.
The source of water for the ECCS pumps is automatically switched to the containment recirculation sumps. The low head residual heat removal (RHR) pumps and containment spray pumps draw the water from the containment recirculation sumps, the RHR aum)s pump the water through the RHR heat i exchangers, inject the water Jacc into the RCS. and upon manual alignment I supply the cooled water to the other ECCS pumps. Switchover from the RWST to SEABROOK - UNIT 1 B 3/4 3-2 Amendment No. 34 1
- l. INSTRUMENTATION
(' '
BASES 3/4 3.1 and 3/4 3.2 REACTOR TRIP SYSTEM and ENGINEERED SAFETY FEATURES ACTUATION SYSTEM INSTRUMENTATION (Continued) the containment recirculation sumps must occur before the RWST empties to prevent damage to the ECCS pumps and a loss of core cooling capability. For similar reasons, switchover must not occur before there is sufficient water in the containment sump to provide sufficient net positive suction head (NPSH) to support ECCS pump operation. Furthermore, early switchover must not occur to ensure that sufficient borated water is injected from the RWST. This ensures the reactor remains shut down in the recirculation mode. To satisfy these requirements. the RWST Level Low-Low Allowable Value/ Trip Setpoint has both upper and lower limits. The lower limit ensures switchover occurs before the RWST empties to prevent ECCS pump damage while the upper limit ensures the l reactor remains shut down and that tnere is adequate water inventory in the l containment recirculation sumps to provide ECCS pump suction.
The Engineered Safety Features Actuation System senses selected plant parameters and determines whether or not predetermined limits are being exceeded. If they are, the signals are combined into logic matrices sensitive to combinations indicative of various accidents, events, and transients. Once the required logic combination is completed the system sends actuation signals to those Engineered Safety Features components whose aggregate function best serves the requirements of the condition. As an example, the following actions may be initiated by the Engineered Safety Features Actuation System to mitigate the consequences of a steam line break or loss-of-coolant accident: (1) Safety SEABROOK - UNIT 1 B 3/4 3-2A Amendment No. 34
s o
1 1
Section IV Determination of Significant flazards for the Proposed Change Page 6
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ___ _ _ l
f
,o
\' *
<e
} I V., DETERMINATION OF SIGNIFICANT HAZARDS FOR Tlif PROPOSED CIIANGE License Amendment Request (LAR) 97-07 proposes a change to the Seabrook Station Technical Specifications (TS), Engineered Safety Features Actuation System Instrumentation Trip Setpoints, Table 3.3-4, Functional Unit 8.b, RWST Level--Low Low, and associated Bases Section 3/4.3.2. The proposed change will revise the Refueling Water Storage Tank (RWST) setpoint associated with Automatic Switchover to the Containment Sump. The new setpoint proposed is the result of a revised setpoint calculation which increases design margin and enhances the setpoint by providing both an upper and lower allowable value to more closely satisfy design basis requirements.
In accordance with 10 CFR 50.92, North Atlantic has reviewed the proposed change and has concluded that it does not involve a significant hazards consideration (SHC). The basis for the conclusion that the proposed change does not involve a SilC is as follows:
- 1. The proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.
The proposed change does not adversely affect accident initiators or precursors and does not alter the design assumptions affecting the ability of the RWST and the ECCS pumps to mitigate the consequences of an accident.
Revising the RWST Level Low-Low setpoint has a negligible effect on the operating margin for the RWST. The revised setpoint assures that the minimum RWST volume assumed in the accident analyses is injected prior to switchover to the recirculation mode. The effect on containment flood level, equipment qualification, and pil of the containment sump and the containment spray fluid, remain within the limits assumed in the accident analyses.
Therefore, the proposed change does r.ot involve a significant increase in the probability or consequences of an accident previously evaluated.
- 2. The proposed change does not create the poss;bility of a new or different kind of accident from any previously analyzed.
The setpoint change does not affect the function of the level monitoring channels or any function i of the accident mitigation equipment associated with the RWST. No new components or physical changes are involved with this change. There are no changes to the source term, containment isolation or radiological release assumptions used in evaluating the radiological consequences in the Seabrook Station UFSAR. The new setpoint will continue to initiate the automatic ECCS transfer from the injection mode to the recirculation mode and provide the alarm to alert the operator (s) to begin the manual actions necessary to complete the transfer to the recirculation mode. Manual operator action is required to complete the switchover to the recirculation mode. With the new setpoint, sufficient time remains available for the operator (s) to complete the transfer prior to receipt of the RWST EMPTY alarm and reaching the vortexing level in the RWST. Therefore, the proposed change does not create the possibility of a new or different kind of accident from any previously analyzed.
Page*
7
-s ,
e .
- 3. The proposed change does not involve a significant reduction in a margin of safety.
The design bases for the RWST 1,cvel 1.ow-1.ow setpoint is to ensure that the minimum volume of water to support the assumptions made in the safety analysis is injected prior to switchover and that ther, is adequate time available for the operators to complete the manual actions necessary to co.aplete the switchover to the recirculation mode prior to actuation of the RWST
!!MPTY alarm. The minimum injection volume assumed in the accident analyses, and time required for the operator (s) to initiate and complete manual actions to complete switchover to the recirculation mode prior to receipt of the RWST EMPTY alt.;m, remains unaffected by this change. Therefore, the proposed change does not involve a significant reduction in a margin of safety.
liased on the above evaluation, North Atlantic concludes that the proposed change does not constitute a significant hazard.
l l
page 8 l
l I ___-_____________________-a
g4 .
cy Sections V & VI l'roposed Schedule for License Amendment Issuance and Effectiveness and EnvironmentalImpact Assessment I
f l
i i
l Page 9
g'- .
V. PROPOSED SCilEDULE FOR LICENSE AMENDMENT ISSUANCE AND DTECTIVENESS f
North Atlantic requests NRC review of License Amendment Request 97-07 and issuance of a license amendment by November 30,1998, having immediate effectiveness and implementation required within 60 days.
VI. EfLVJRONMENTAL IMPACT ASSESSMENT North Atlantic has reviewed the proposed license amendment against the criteria of 10 CFR 51.22 for environmental considerations. The proposed change does not involve a significant hazards consideration, nor increase the types and amounts of efnuent that may be released offsite, nor significantly increase individual or cumulative occupational radiation exposures, llased on the foregoing, North Atlantic concludes that the proposed change meets the criteria delineated in 10 CFR 51.22(c)(9) for a categorical exclusion from the requirements for an Environmental Impact Statement.
i l
l l
Page 10
- . _ _ _ _ _ _ _ ______________________________J