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f - | |||
g TABLE 3.3.3-2(Continued) - | |||
EfERGENCY CORE COOLING SYSTEM ACTUATION INSTIMENTATIOM SETP0lNTS , | |||
ALLOWABLE TRIP FINICTION TRIP SETP0 INT VALUE i | |||
n p, ~o;2 ' ~ | |||
q C. DIVISION 3 TRIP SYSTEM . | |||
q-p | |||
: 1. HPCS SYSTEM n s | |||
[ . | |||
Reacter Vessel Water Level - Low Low, Level 2 | |||
: a. >- 50 inches * >- 57 inches 3 C.n | |||
: b. Drywell Pressure - Hi @ i 1.69 e (b | |||
: c. Reacter Vessel Water .evel - High, Level 8 7 1.89 P s 9* 5 | |||
: d. Deleted | |||
?55.5 lies * . 156inc o | |||
,,y | |||
: e. Deleted 3T ! | |||
: f. Pische Pressure - High > 120 psig > 110 psig O 5 | |||
: g. System ow Rate - Low i 1000 pm F 900 p m E. l | |||
: h. Manual Intiation M M $_%{ | |||
., [. D. : LOSS OF POWER E 1. 4.16 kV Ese Bus Undervoltage | |||
~ | |||
( , | |||
i (LossofVo1 age # | |||
: a. 4.16 kV Suses l | |||
; -l | |||
: 1) Divisions 1 and 2 2625 i 131 volts with 2625 1 262 volts with ! | |||
i 10 seconds time delay 1 11 seconds time delay 2496 i 125 volts with 2496 i 250 volts with | |||
> 4 seconds time delay > 3 seconds time delay , | |||
: 2) Division 3 | |||
' 2870 i 143 volts with 2870 | |||
* 287 volts with i 10 seconds time delay i 11 seconds time delay F | |||
*See Bases Figure 5 3/4 3-1. | |||
3 IThese are inverse time delay voltage relays or instantaneous voltage relays with a time delay. The voltages shown are the maximum that will not result in a trip. Lower voltage conditions will result in i 2 decreased trip times. i | |||
. l | |||
~ | |||
jn"E8ERUssjb | |||
t TABLE 3.3.3-2(Continued) g EERGEKY CORE COOLIE SYSTEN ACTMTION INSTRISENTATION SETFOINTS - - | |||
E ~ | |||
i TRIP FUNCTION ALLOWBLE TRIP SETPOINT VALUE h 2. -4.16 kV Ese (DegradedVo ag) | |||
Bus Undervoltage | |||
: a. 4.16 kV Buses > | |||
P b | |||
: 1) Divistens 1, 2 and 3 14 i X) volts with l 14 i S veits with . | |||
10 1 1 seconds time 10 i I seconds time delay with LOCA stenal delay wfth LOCA signal er er 5 i 0.5 minutes time 5 1 0.5 minutes time de without LOCA del without LOCA si g 1 si 1 | |||
.. y 2 n . | |||
r N | |||
>* i | |||
, .-~. . | |||
TABLE 3.3.3-2 (Continued) - | |||
g EE RGENCY CORE C00LIIr 3Y5TUrXETUATIGN INSTRtN NTATION SETPOINTS ALLOWA8LE E TRIP FUNCTION TRIP SETPOINT - | |||
VALUE 4 o 2 ~ | |||
5 O C. DIVISION 3 TRIP SYSTEM . | |||
: 1. HPCS SYSTEM E | |||
U a. Re ator Vessel Water Level - Low Low, Level 2 >- 50 inches * >- 57 inches | |||
* h,6[o 3 | |||
n N b. | |||
c. | |||
Drywell Pressure - Hif Reactor Vessel Water .evel - High, Level 8 i 1.69 psig | |||
'-Y 55.5 inches | |||
* i 1.89 psig* | |||
i 56 inches S | |||
A $ | |||
: d. Deleted i | |||
: e. Deleted Pump Discharge Pressure - High > 120 psig > 110 psig 3E'2 b | |||
~h f. | |||
: g. HPCS System Flow Rate - Low 5_ I | |||
> 1000 gym > 900 gym j 3 n) | |||
Manual Intiation | |||
: h. R.A. R.A. | |||
} | |||
D. LOSS OF POWER R 1. 4.16 kV Emergency Bus Undervoltage . | |||
.. * (Loss of Voltage)# | |||
Y - | |||
: a. 4.16 kV Buses l | |||
: 1) Divisions 1 and 2 2625 i 131 volts with 2625 1 262 volts with 1 10 second time delay 1 11 second tint delay 2496 i 125 volts with 2496 i 250 volts with | |||
> 4 second time delay > 3 second time delay | |||
: 2) Division 3 2870 i 143 volts with 2870 1 287 volts with 1 10 second time delay 1 11 second time delay F TABLE NOTATIONS | |||
= | |||
*See Bases Figure B 3/4 3-1. | |||
#These are inverse time delay voltage relays or instantaneous voltage relays with a time delay. The voltages | |||
,F shown are the maximum that will not result in a trip. Lower voltage conditions will result in decreased trip times. | |||
M N.A. Not Applicable | |||
:: I | |||
.- -s. | |||
t - | |||
..) | |||
s .e TABLE 3.3.3-2 (Continued) ,- | |||
E EDERGENCY CORE COOLING SYSTEM ACTUATION INSTIRNENTATION SETPOINTS - ! | |||
M! | |||
g- ALLOWR8LE | |||
. i m | |||
TRIP FINICTION TRIP SETPOINT VALUE 6 | |||
8 g D. LOSS OF POWER'(Continued) - | |||
Q 2. 4.16 kV Ese Bus Undervoltage | |||
~ | |||
l (negraded Vo tage) >3g70 - ,23g/ | |||
: a. 4.16 kV Buses p F l , | |||
: 1) Divisions 1, 2 and 3 14 | |||
* 76) volts with | |||
~ | |||
4 1 3 volts with - | |||
i 10 | |||
* 1 seconds time 10 i 1 seconds time delay - | |||
delay with LOCA signal with LOCA signal ! | |||
or or ! | |||
5 | |||
* 0.5 minutes time 5 | |||
* 0.5 minutes time delay delay without LOCA without LOCA signal ; | |||
signal k* s Y | |||
f I | |||
2 Y | |||
.M E | |||
t | |||
. . - . _ . . ~ _ - .. . - - _m. _ m._...__._ _ . _ _ _ .- _ _ ._ ..__ _ _ _ _ _ _ _ | |||
t ATTACHMENT C | |||
' SIGNIFICANT HAZARDS CONSIDERATION | |||
~ | |||
Commonwealth Edison (Comed) ha evaluated this proposed amendment and determined that it | |||
' involves no signi6 cant hazards consideration. . According to 10 CFR 50.92(c), a proposed amendment to an operating license involves no significant hazards consideration if operation of facility in accordance with the proposed amendment will not: | |||
Involve a significant increase in the probability or consequences of an accident previously , | |||
evaluated; I | |||
Create the possibility of a new or different kind of accident from any previously analyzed; or Involve a significant reduction in a margin of safety. | |||
Comed proposes to amend Appendix A, Technical Specifications, of Facility Operating Licenses | |||
' NPF-11 and NPF-18, LaSalle County Station Units 1 and 2. %e proposed amendment requests a - | |||
change to the Technical Specifications to modify the degraded voltage second level undervoltage relay , | |||
setpoint and allowable values. The affected Technical Specification is Technical Specification 3/4.3.3, ECCS System Actuation Instrumentation, and Technical Specification Table 3.3.3-2, ECCS System L Actuation Instrumentation Setpoints. The proposed changes are supported by calculations that address known instrument errors and plant accident bus loading conditions. | |||
The determination that the criteria set forth in 10 CFR 50.92 are met for this amendment request is | |||
;: indicated below: - | |||
; 2 | |||
- Does the change involve a significant increase in the probability or consequences of an accident | |||
: previously evaluated? | |||
l %e setpoint change does not change the logic or function of the degraded voltage protection L circuits as described in UFSAR Section 8.2.3. Hey also do not reduce the reliability of these l ' circuits. %e increase in the degraded voltage protection circuit setpoint is conservative L compared to the existing setpoint. There is no change as a result of this amendment to the underlying accident and transient analyses that support operations of.LaSalle County Station. | |||
Inadvertent or spurious operation of the degraded voltage protection function will initiate L | |||
loading of the safe shutdown loads on the diesel generators and is not assumed to initiate an accident. %e proposed degraded voltage setpoints are low enough to prevent spurious actuations given the expected offsite grid voltages. After implementation of this amendment, no operator actions are required for equipment operations in response to degraded voltage conditions. | |||
P his change does not affect the initiators or precursors of any accident previously evaluated. | |||
, his change will not increase the likelihood that a transient initiating event will occur because | |||
, transients are initiated by equipment malfunction and/or catastrophic system failure. | |||
1. | |||
t C-1 L | |||
ATTACHMENT C SIGNIFICANT HAZARDS CONSIDERATION The consequences of accidents previously evaluated are not increased. He proposed change does not affect the required level of availability of systems required to mitigate the accidents considered in the analyses. The proposed changes will ensure that the Class 1E equipment will be capable of starting and operating during a design basis accident with degraded offsite grid voltage. %e increase in the level of confidence is the result of the more rigorous methodology used to determine limiting Class 1E bus voltages at the minimum expected l offsite AC voltage. %ese calculations demonstrate that the degraded voltage relays will not I actuate follomng a block start of the electrical loads that are automatically actuated by or as a consequence of the LOCA signal if the switchyard voltage remains above 352 kV. | |||
If the grid voltage drops below 352 kV, then the analytical limit of 3814 volts for proper i operation of class 1E loads connected to each 4.16 kV Class 1E bus is assured by transfer to I the respective onsite power sources (Emergency Diesel Generators (EDGs)) by the degraded i voltrge logic. | |||
Herefore this proposed amendment does not involve a significant increase in the probability or consequences of an accident previously evaluated. | |||
: 2) Create the possibility of a new or different kind of accident from any accident previously evaluated because: | |||
Setpoint methodology established the bases to ensure that, with known errors, the relays will , | |||
detect degraded voltage conditions and transfer safety loads to the EDGs at a voltage level l adequate to ensure proper safety equipment performance and to prevent equipment damage. j The 2 3870 volt setpoint and the 2 3814 volt allowable value includes adequate tolerance to ); | |||
calibrate the relay trip units while ensuring that the Class 1E bus voltage will remain above the analytical limits. | |||
These setpoint changes will ensure that adequate voltages will be available for the continuous operation of safety-related equipment required to function during a LOCA. These proposed changes will also ensure that adequate voltages will be available for starting any Class 1E equipment. | |||
* l l | |||
l l | |||
C-2 l | |||
1 l | |||
. l l | |||
ATTACHMENT C SIGNIFICANT HAZARDS CONSIDERATION The proposed degraded voltage serpoint change does not change the design of the degraded voltage protection system or its function to protect against degraded offsite power. Actuation of the degraded voltage protection system will initiate a sequence of events that will start the EDG for the associated Class 1E bus, strip loads from the Class 1E bus, open all feed breakers to the Class 1E bus, close the Emergency feed breaker (thus energizing the Class 1E bus from the respective EDG), and initiate starting of the Safe Shutdown equipment supplied by the Clus 1E bus. | |||
Since the scope of this change does not affect the operation of the auxiliary power system or any actions necessary to mitigate the consequences of accidents or achieve safe shutdown, the change does not involve a new or different accident scenario. | |||
Therefore, these proposed changes do not create the possibility of a new or different kind of accident from any accident previously evaluated. | |||
: 3) Involve a significant reduction in the margin of safety because: | |||
The proposed amendment will allow the degraded voltage serpoint to be conservatively established based on new engineering calculations which consider the lowest expected offsite grid voltage and operation of required Class 1E equipment under design basis accident loading conditions. | |||
1 | |||
%e proposed degraded voltage serpoints will ensure that adequate Class 1E bus voltage will be available to support starting and operation of required Class 1E loads. The proposed setpoint includes instrument error to ensure that the lowest possible voltage will not be lower than the degraded voltage analytical limits. Additionally, the proposed serpoints are low enough to prevent spurious actuations due to expected Ductuations in the grid voltage. The new setpoints are also set with margin to the minimum Class 1E bus voltage, which is based on a minimum grid voltage of 352 kV, which is less than the expected grid voltage of 354 kV. The proposed changes will provide an increase in the level of protection that currently I exists and will ensure the margin of safety is adequately maintained. | |||
l Therefore, these changes do not involve a significant reduction in the margin of safety. | |||
Therefore, based upon the above evaluation, Comed has concluded that these changes involve no significant hazards consideration. | |||
l l | |||
C-3 | |||
l ATTACHMENT D ENVIRONMENTAL ASSESSMENT STATEMENT APPLICABILITY REVIEW Comed has evaluated this proposed operating license amendment request against the criteria for identification oflicensing and regulatory actions requiring environmental assessment in accordance with 10 CFR 51.21. Comed has determined that the proposed license amendment request meets the criteria for a categorical exclusion set forth in 10 CFR 51.22(c)(9) and as such, has determined that no irreversible consequences exist in accordance with 10 CFR 50.92(b). This determination is based on the fact that this change is being proposed as an amendment to a license issued pursuant to 10 CFR 50 that changes a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, or that change an inspection or a surveillance requirement, and the amendment meets the following specific criteria: | |||
: 6) the amendment involves no significant hazards consideration. | |||
As demonstrated in Attachment C, this proposed amendment does nat involve any significant hazards consideration. | |||
(u) there is no significant change in the types or significant increase in the amouitts of any effluent that may be released offsite. | |||
As documented in Attachment A, there will be no change in the types or significant increase in the amounts of any effluents released offsite. | |||
i Qii) there is no significant increase in individual or cumulative occupational radiation exposure. | |||
'Ihe proposed changes will not result in changes in the operation or configuration of the facility. There will be no change in the level of controls or methodology used for processing of radioactive effluents or handling of solid radioactive waste, nor will the proposal result in any change in the norma" radiation levels within the plant. Therefore, there will be no increase in individual or cumulative occupational radiation exposure resulting from this change. | |||
l-l l | |||
l D-1}} |
Latest revision as of 17:18, 16 December 2020
ML20195E054 | |
Person / Time | |
---|---|
Site: | LaSalle ![]() |
Issue date: | 11/09/1998 |
From: | COMMONWEALTH EDISON CO. |
To: | |
Shared Package | |
ML20195E053 | List: |
References | |
NUDOCS 9811180223 | |
Download: ML20195E054 (8) | |
Text
_ . _ _ . _ _ . _ _ . _ _ . . - . __. . _ _ . _ . _ . _ . _. __ .
f -
g TABLE 3.3.3-2(Continued) -
EfERGENCY CORE COOLING SYSTEM ACTUATION INSTIMENTATIOM SETP0lNTS ,
ALLOWABLE TRIP FINICTION TRIP SETP0 INT VALUE i
n p, ~o;2 ' ~
q C. DIVISION 3 TRIP SYSTEM .
q-p
- 1. HPCS SYSTEM n s
[ .
Reacter Vessel Water Level - Low Low, Level 2
- a. >- 50 inches * >- 57 inches 3 C.n
- b. Drywell Pressure - Hi @ i 1.69 e (b
- c. Reacter Vessel Water .evel - High, Level 8 7 1.89 P s 9* 5
- d. Deleted
?55.5 lies * . 156inc o
,,y
- e. Deleted 3T !
- f. Pische Pressure - High > 120 psig > 110 psig O 5
- g. System ow Rate - Low i 1000 pm F 900 p m E. l
- h. Manual Intiation M M $_%{
., [. D. : LOSS OF POWER E 1. 4.16 kV Ese Bus Undervoltage
~
( ,
i (LossofVo1 age #
- a. 4.16 kV Suses l
- -l
- 1) Divisions 1 and 2 2625 i 131 volts with 2625 1 262 volts with !
i 10 seconds time delay 1 11 seconds time delay 2496 i 125 volts with 2496 i 250 volts with
> 4 seconds time delay > 3 seconds time delay ,
- 2) Division 3
' 2870 i 143 volts with 2870
- 287 volts with i 10 seconds time delay i 11 seconds time delay F
- See Bases Figure 5 3/4 3-1.
3 IThese are inverse time delay voltage relays or instantaneous voltage relays with a time delay. The voltages shown are the maximum that will not result in a trip. Lower voltage conditions will result in i 2 decreased trip times. i
. l
~
jn"E8ERUssjb
t TABLE 3.3.3-2(Continued) g EERGEKY CORE COOLIE SYSTEN ACTMTION INSTRISENTATION SETFOINTS - -
E ~
i TRIP FUNCTION ALLOWBLE TRIP SETPOINT VALUE h 2. -4.16 kV Ese (DegradedVo ag)
Bus Undervoltage
- a. 4.16 kV Buses >
P b
- 1) Divistens 1, 2 and 3 14 i X) volts with l 14 i S veits with .
10 1 1 seconds time 10 i I seconds time delay with LOCA stenal delay wfth LOCA signal er er 5 i 0.5 minutes time 5 1 0.5 minutes time de without LOCA del without LOCA si g 1 si 1
.. y 2 n .
r N
>* i
, .-~. .
TABLE 3.3.3-2 (Continued) -
g EE RGENCY CORE C00LIIr 3Y5TUrXETUATIGN INSTRtN NTATION SETPOINTS ALLOWA8LE E TRIP FUNCTION TRIP SETPOINT -
VALUE 4 o 2 ~
5 O C. DIVISION 3 TRIP SYSTEM .
- 1. HPCS SYSTEM E
U a. Re ator Vessel Water Level - Low Low, Level 2 >- 50 inches * >- 57 inches
- h,6[o 3
n N b.
c.
Drywell Pressure - Hif Reactor Vessel Water .evel - High, Level 8 i 1.69 psig
'-Y 55.5 inches
- i 1.89 psig*
i 56 inches S
A $
- d. Deleted i
- e. Deleted Pump Discharge Pressure - High > 120 psig > 110 psig 3E'2 b
~h f.
- g. HPCS System Flow Rate - Low 5_ I
> 1000 gym > 900 gym j 3 n)
Manual Intiation
- h. R.A. R.A.
}
D. LOSS OF POWER R 1. 4.16 kV Emergency Bus Undervoltage .
.. * (Loss of Voltage)#
Y -
- a. 4.16 kV Buses l
- 1) Divisions 1 and 2 2625 i 131 volts with 2625 1 262 volts with 1 10 second time delay 1 11 second tint delay 2496 i 125 volts with 2496 i 250 volts with
> 4 second time delay > 3 second time delay
- 2) Division 3 2870 i 143 volts with 2870 1 287 volts with 1 10 second time delay 1 11 second time delay F TABLE NOTATIONS
=
- See Bases Figure B 3/4 3-1.
- These are inverse time delay voltage relays or instantaneous voltage relays with a time delay. The voltages
,F shown are the maximum that will not result in a trip. Lower voltage conditions will result in decreased trip times.
M N.A. Not Applicable
- I
.- -s.
t -
..)
s .e TABLE 3.3.3-2 (Continued) ,-
E EDERGENCY CORE COOLING SYSTEM ACTUATION INSTIRNENTATION SETPOINTS - !
M!
g- ALLOWR8LE
. i m
TRIP FINICTION TRIP SETPOINT VALUE 6
8 g D. LOSS OF POWER'(Continued) -
Q 2. 4.16 kV Ese Bus Undervoltage
~
l (negraded Vo tage) >3g70 - ,23g/
- a. 4.16 kV Buses p F l ,
- 1) Divisions 1, 2 and 3 14
- 76) volts with
~
4 1 3 volts with -
i 10
- 1 seconds time 10 i 1 seconds time delay -
delay with LOCA signal with LOCA signal !
or or !
5
- 0.5 minutes time 5
signal k* s Y
f I
2 Y
.M E
t
. . - . _ . . ~ _ - .. . - - _m. _ m._...__._ _ . _ _ _ .- _ _ ._ ..__ _ _ _ _ _ _ _
t ATTACHMENT C
' SIGNIFICANT HAZARDS CONSIDERATION
~
Commonwealth Edison (Comed) ha evaluated this proposed amendment and determined that it
' involves no signi6 cant hazards consideration. . According to 10 CFR 50.92(c), a proposed amendment to an operating license involves no significant hazards consideration if operation of facility in accordance with the proposed amendment will not:
Involve a significant increase in the probability or consequences of an accident previously ,
evaluated; I
Create the possibility of a new or different kind of accident from any previously analyzed; or Involve a significant reduction in a margin of safety.
Comed proposes to amend Appendix A, Technical Specifications, of Facility Operating Licenses
' NPF-11 and NPF-18, LaSalle County Station Units 1 and 2. %e proposed amendment requests a -
change to the Technical Specifications to modify the degraded voltage second level undervoltage relay ,
setpoint and allowable values. The affected Technical Specification is Technical Specification 3/4.3.3, ECCS System Actuation Instrumentation, and Technical Specification Table 3.3.3-2, ECCS System L Actuation Instrumentation Setpoints. The proposed changes are supported by calculations that address known instrument errors and plant accident bus loading conditions.
The determination that the criteria set forth in 10 CFR 50.92 are met for this amendment request is
- indicated below
- -
- 2
- Does the change involve a significant increase in the probability or consequences of an accident
- previously evaluated?
l %e setpoint change does not change the logic or function of the degraded voltage protection L circuits as described in UFSAR Section 8.2.3. Hey also do not reduce the reliability of these l ' circuits. %e increase in the degraded voltage protection circuit setpoint is conservative L compared to the existing setpoint. There is no change as a result of this amendment to the underlying accident and transient analyses that support operations of.LaSalle County Station.
Inadvertent or spurious operation of the degraded voltage protection function will initiate L
loading of the safe shutdown loads on the diesel generators and is not assumed to initiate an accident. %e proposed degraded voltage setpoints are low enough to prevent spurious actuations given the expected offsite grid voltages. After implementation of this amendment, no operator actions are required for equipment operations in response to degraded voltage conditions.
P his change does not affect the initiators or precursors of any accident previously evaluated.
, his change will not increase the likelihood that a transient initiating event will occur because
, transients are initiated by equipment malfunction and/or catastrophic system failure.
1.
t C-1 L
ATTACHMENT C SIGNIFICANT HAZARDS CONSIDERATION The consequences of accidents previously evaluated are not increased. He proposed change does not affect the required level of availability of systems required to mitigate the accidents considered in the analyses. The proposed changes will ensure that the Class 1E equipment will be capable of starting and operating during a design basis accident with degraded offsite grid voltage. %e increase in the level of confidence is the result of the more rigorous methodology used to determine limiting Class 1E bus voltages at the minimum expected l offsite AC voltage. %ese calculations demonstrate that the degraded voltage relays will not I actuate follomng a block start of the electrical loads that are automatically actuated by or as a consequence of the LOCA signal if the switchyard voltage remains above 352 kV.
If the grid voltage drops below 352 kV, then the analytical limit of 3814 volts for proper i operation of class 1E loads connected to each 4.16 kV Class 1E bus is assured by transfer to I the respective onsite power sources (Emergency Diesel Generators (EDGs)) by the degraded i voltrge logic.
Herefore this proposed amendment does not involve a significant increase in the probability or consequences of an accident previously evaluated.
- 2) Create the possibility of a new or different kind of accident from any accident previously evaluated because:
Setpoint methodology established the bases to ensure that, with known errors, the relays will ,
detect degraded voltage conditions and transfer safety loads to the EDGs at a voltage level l adequate to ensure proper safety equipment performance and to prevent equipment damage. j The 2 3870 volt setpoint and the 2 3814 volt allowable value includes adequate tolerance to );
calibrate the relay trip units while ensuring that the Class 1E bus voltage will remain above the analytical limits.
These setpoint changes will ensure that adequate voltages will be available for the continuous operation of safety-related equipment required to function during a LOCA. These proposed changes will also ensure that adequate voltages will be available for starting any Class 1E equipment.
- l l
l l
C-2 l
1 l
. l l
ATTACHMENT C SIGNIFICANT HAZARDS CONSIDERATION The proposed degraded voltage serpoint change does not change the design of the degraded voltage protection system or its function to protect against degraded offsite power. Actuation of the degraded voltage protection system will initiate a sequence of events that will start the EDG for the associated Class 1E bus, strip loads from the Class 1E bus, open all feed breakers to the Class 1E bus, close the Emergency feed breaker (thus energizing the Class 1E bus from the respective EDG), and initiate starting of the Safe Shutdown equipment supplied by the Clus 1E bus.
Since the scope of this change does not affect the operation of the auxiliary power system or any actions necessary to mitigate the consequences of accidents or achieve safe shutdown, the change does not involve a new or different accident scenario.
Therefore, these proposed changes do not create the possibility of a new or different kind of accident from any accident previously evaluated.
- 3) Involve a significant reduction in the margin of safety because:
The proposed amendment will allow the degraded voltage serpoint to be conservatively established based on new engineering calculations which consider the lowest expected offsite grid voltage and operation of required Class 1E equipment under design basis accident loading conditions.
1
%e proposed degraded voltage serpoints will ensure that adequate Class 1E bus voltage will be available to support starting and operation of required Class 1E loads. The proposed setpoint includes instrument error to ensure that the lowest possible voltage will not be lower than the degraded voltage analytical limits. Additionally, the proposed serpoints are low enough to prevent spurious actuations due to expected Ductuations in the grid voltage. The new setpoints are also set with margin to the minimum Class 1E bus voltage, which is based on a minimum grid voltage of 352 kV, which is less than the expected grid voltage of 354 kV. The proposed changes will provide an increase in the level of protection that currently I exists and will ensure the margin of safety is adequately maintained.
l Therefore, these changes do not involve a significant reduction in the margin of safety.
Therefore, based upon the above evaluation, Comed has concluded that these changes involve no significant hazards consideration.
l l
C-3
l ATTACHMENT D ENVIRONMENTAL ASSESSMENT STATEMENT APPLICABILITY REVIEW Comed has evaluated this proposed operating license amendment request against the criteria for identification oflicensing and regulatory actions requiring environmental assessment in accordance with 10 CFR 51.21. Comed has determined that the proposed license amendment request meets the criteria for a categorical exclusion set forth in 10 CFR 51.22(c)(9) and as such, has determined that no irreversible consequences exist in accordance with 10 CFR 50.92(b). This determination is based on the fact that this change is being proposed as an amendment to a license issued pursuant to 10 CFR 50 that changes a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, or that change an inspection or a surveillance requirement, and the amendment meets the following specific criteria:
- 6) the amendment involves no significant hazards consideration.
As demonstrated in Attachment C, this proposed amendment does nat involve any significant hazards consideration.
(u) there is no significant change in the types or significant increase in the amouitts of any effluent that may be released offsite.
As documented in Attachment A, there will be no change in the types or significant increase in the amounts of any effluents released offsite.
i Qii) there is no significant increase in individual or cumulative occupational radiation exposure.
'Ihe proposed changes will not result in changes in the operation or configuration of the facility. There will be no change in the level of controls or methodology used for processing of radioactive effluents or handling of solid radioactive waste, nor will the proposal result in any change in the norma" radiation levels within the plant. Therefore, there will be no increase in individual or cumulative occupational radiation exposure resulting from this change.
l-l l
l D-1