ML17313A418
| ML17313A418 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 06/09/1998 |
| From: | ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR |
| To: | |
| Shared Package | |
| ML17313A417 | List: |
| References | |
| NUDOCS 9806160236 | |
| Download: ML17313A418 (25) | |
Text
Enclosure 1 Marked-up ITS Pages 9806'f60236 980609 PDR ADQCK 05000528 P PDR'
k SITs-Oper ating 3.5.1 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS) 3.5. 1 Safety Injection Tanks (SITs) - Operating LCO 3.5.1 Four SITs shall be OPERABLE.
APPLICABILITY: MODES 1 and 2.
MODES 3 and 4 with pressurizer pressure ~ 1837 psia.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. One SIT inoperable due A.l Restore SIT to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to boron concentration OPERABLE status.
not within limits.
B. One SIT inoperable for B.l Restore SIT to reasons other than OPERABLE status. Wf haccvg Condition A.
C. Required Action and C.l -
Be in MODE 3. 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> associated Completion Time of Condition A AND or B not met.
C.2 Reduce pressurizer 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> pressure to
( 1837 psia.
D. Two or more SITs D.l Enter LCO 3.0.3. Immediately inoperable.
bR Or e..5XT'hoPKro 4 4 Q~g +a
<~a,biliky fc Vev'<4y lese o~ pressaue.
~
PALO VERDE UNITS 1.2,3 3.5.1-1 AMENDMENT NO. ~
l(
SITs-Shutdown 3.5.2 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS) 3.5.2 Safety Injection Tanks (SITs)-Shutdown LCO 3.5.2 Four SITs shall be OPERABLE with a borated water volume
) 39K wide range indication and < 83K wide range indication; OR Three SITS shall be OPERABLE with a borated water volume
> 60K wide range indication and < 83K wide range indication.
APPLICABILITY: MODES 3 and 4 with pressurizer pressure < 1837 psia.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. One required SIT A. 1 Restore required SIT 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> inoperable due to to OPERABLE status.
boron concentration not within limits.
B. One required SIT B. 1 Restore required SIT inoperable for reasons to OPERABLE status. wf Aors,rs other than Condition A.
C. Inoperability of the C.l Be in MODE 5. 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> required SIT was discovered but not restored while in ITS 3.5.1, "SITs-Operating" OR Required Action and associated Completion Time of Condition A or B not met.
D. Two or more required D.l Enter LCO 3.0.3. Immediately SITs inoperable.
eoc re~srod eXT Sssopevol le d e.*sssssc4sisg& vcrs4y 4S/ol or tsresSurc.
PALO VERDE UNITS 1,2.3 3.5.2-1 AMENDMENT NO.
I>
II fl
Enclosure 2 Retyped ITS Pages
SITs-Operating 3.5.1 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS) 3.5. 1 Safety Injection Tanks (SITs) - Operating LCO 3.5. 1 Four SITs shall be OPERABLE.
APPLICABILITY: MODES 1 and 2, MODES 3 and 4 with pressurizer pressure > 1837 psia.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. One SIT inoperable due A.1 Restore SIT to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to boron concentration OPERABLE status.
not within limits.
OR One SIT inoperable due to inability to verify level or pressure.
B. One SIT inoperable for B.l Restore SIT to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> reasons other than OPERABLE status.
Condition A.
C. Required Action and C.l Be in MODE 3. 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> associated Completion Time of Condition A AND or B not met.
C.2 Reduce pressurizer 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> pressure to
< 1837 psia.
D. Two or more SITs D.1 Enter LCO 3.0.3. Immediately inoperable.
PALO VERDE UNITS 1.2.3 3.5.1-1 AMENDMENT NO. 447-
SITs -Shutdown 3.5.2 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS) 3.5.2 Safety Injection Tanks (SITs)-Shutdown LCO 3.5.2 Four SITs shall be OPERABLE with a borated water volume
> 39K wide range indication and ( 83K wide range indication; OR Three SITS shall be OPERABLE with a borated water volume
> 60X wide range indication and ( 83K wide range indication.
APPLICABILITY: MODES 3 and 4 with pressurizer pressure ( 1837 psia.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. One required SIT A.l Restore required SIT 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> inoperable due to to OPERABLE status.
boron concentration not within limits.
OR One required SIT inoperable due to inability to verify level or pressure.
One required SIT B. 1 Restore reauired SIT 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> inoperable for reasons to OPERABLE status.
other than Condition A.
C. Inoperability of the C. 1 Be in MODE 5. 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> required SIT was discovered but not restored while in ITS 3.5.1, "SITs-Operating" OR Required Action and associated Completion Time of Condition A or B not met.
D. Two or more required D. 1 Enter LCO 3.0.3. Immedi ately SITs inoperable.
PALO VERDE UNITS 1.2.3 3.5.2-1 AMENDMENT NO. kk7-
Enclosure 3 Marked-up ITS Bases Pages
SITs-Operating 8 3.5.1 BASES ACTIONS A.l If the boron concentration of one SIT is not within limits, the SIT must be returned to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
If the boron concentration is not within limits, ability to maintain subcriticality or minimum boron precipitation time may be reduced, but the reduced concentration effects on core subcriticality during reflood ar'e minor. Boiling of the ECCS water in the core during reflood concentrates the boron in the saturated liquid that remains in the core. In addition. the volume of the SIT is still available for injection. Since the boron requirements are based on the
'da average boron concentration of the total volume of three SITs, the consequences are less severe than they would be a SIT were not available for injection. Thus. 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> is if allowed to return the boron concentration to within limits.
inset>"
cs t7eul pa.v~gyc ph 8.1 ar ~~ t~a4it+ W ver'< lese l or pr<<<cu'4E If one SIT is inoperable for a reason other than boron concentr tion, the SIT must be returned to OPERABLE status wi s r In this Condition, the required contents of three S s cannot be assumed to reach the core during a LO . e o e s erity o e ou a A occur n these co itions, the our Comple n Time to op the valve emove power the valve. r restore th p per water olume or nit gen cover pr sure ensure at AAct Insert 8 rompt ac on will be t n to return e inoperabl IT to RK net% OPERAB status. The ompletion Ti minimizes QR.vo )+ckpk pote ~al for expos e of the pla to a LOCA er these co itio s.
ACTIONS C. 1 and C.2 If the SIT cannot be restored to OPERABLE status within the associated Completion Time, the plant must be brought to a NODE in which the LCO does not apply. To achieve this status. the plant must be brought to at least NODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and pressurizer pressure reduced to ( 1837 psia within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. The allowed Completion Times are reasonable, based on operating experience. to reach the required plant conditions from full power conditions in an orderly manner and without challenging plant systems.
(continued)
PALO VERDE UNITS 1.2,3 B 3.5.1-7 REVISION g I
'NSERT A ITS BASES B 3.5.1 ACTION A.1 If one SIT is inoperable due to the inability to verify level or pressure, the SIT must be returned to operable status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. Section 7.4 of NUREG-1366 (Ref. 5) discusses surveillance requirements in technical specifications for the instrument channels used in the measurement of water level and pressure in SITs. The following statement is made in Section 7.4 of NUREG-1366 (Ref. 5):
"The combination of redundant level and pressure instrumentation [for any single SIT] may provide sufficient information so that it may not be worthwhile to always attempt to correct drift associated with one instrument [with resulting radiation exposures during entry into containment] if there were sufficient time to repair one in the event that a second one became inoperable. Because these instruments do not initiate a safety action, it is reasonable to extend the allowable outage for them. The [NRC] staff, therefore, recommends that an additional condition be established for the specific case, where 'One accumulator
[SIT] is inoperable due to the inoperability of water level and pressure channels,'n which the completion time to restore the accumulator to operable status will be 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. While technically inoperable, the accumulator would be available to fulfillits safety function during this time and, thus, this change would have a negligible increase in risk."
INSERT B ITS BASES B 3.5.1 ACTION B.1 CE NPSD-994 (Ref. 6) provides a series of deterministic and probabilistic findings that support 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> as being either "risk beneficial" or "risk neutral" in comparison to shorter periods for restoring the SIT to OPERABLE status. CE NPSD-994 (Ref. 6) discusses best-estimate analysis for a typical PWR that confirmed that, during large-break LOCA scenarios, core melt can be prevented by either operation of one low pressure safety injection (LPSI) pump or the operation of one high pressure safety injection (HPSI) pump and a single SIT.
CE NPSD-994 (Ref. 6) also discusses plant-specific probabilistic analysis that evaluated the risk-impact of the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> recovery period in comparison to shorter recovery periods.
I I
l l
SITs-Operating B 3.5.1 BASES (continued)
SURVEILLANCE SR 3.5.1.5 REQUIREMENTS (continued) Verification every 31 days that power is removed from each SIT isolation valve operator ensures that an active failure could not result in the undetected closure of a SIT motor operated isolation valve. If this were to occur, only two SITs would be available for injection. given a single failure coincident with a LOCA. Since installation and removal, of power to the SIT isolation valve operators is conducted under administrative control. the 31 day Frequency was chosen to provide additional assurance that power is removed.
SR 3.5.2.5 allows power to be supplied to the motor operated isolation valves when RCS pressure is ( 1500 psia, thus allowing operational flexibility by avoiding unnecessary delays to manipulate the breakers during unit startups or shutdowns. Even with power supplied to the valves, inadvertent closure is prevented by the RCS pressure interlock associated with the valves. Should closure of a valve occur in spite of the interlock. the SI signal provided to the valves would open a closed valve in the event of a LOCA.
REFERENCES 1. IEEE Standard 279-1971.
- 2. UFSAR. Section 6.
- 3. 10 CFR 50.46.
4 UFSAR, Chapter 15.
- 5. NUREG-1366. ecember 1992. l~pro~ew e~4 W ~ec4~ac l ~+<64ca+tcng Surveillance ge ite~c~+s>"
CfOG Qcw+/tp~(lccg~g g ozq gz 'Safe PALO VERDE UNITS 1.2,3 B 3.5.1-10 REVISION E
SITs - Shutdown B 3.5.2 BASES APPLICABILITY In HODES 1 and 2. and HODES 3 and 4 with pressurizer pressure > 1837 psia, the OPERABILITY requirements for SITs are covered by LCO 3.5. 1.
In HODES 3 and 4 with pressurizer pressure < 1837 psia, the reduced borated water volume requirement is acceptable.
based on the stable reactivity condition of the reactor and the limited core cooling requirements.
In HODE 4 with pressurizer pressure < 430 psia, the SIT motor operated isolation valves may be closed to isolate the SITs from the RCS but must remain energized. This allows RCS cooldown and depressurization without discharging the SITs into the RCS or requiring depressurization of the SITs.
In this situation manual actions would be required to open the SIT motor operated isolation valves (i.e.. manually initiated SIAS).
In HODES 5 and 6 the SITs are not requi red and the SIT motor operated isolation valves are closed as requi red to isolate the SITs from the RCS.
ACTIONS A.1 If the boron concentration of one of the required SITs is not within limits, it must be returned to within the limits within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. In this condition, ability to maintain subcriticality or minimum boron precipitation time may be reduced, but the reduced concentration effects on core subcriticality during reflood are minor . Boiling of the ECCS water in the core during reflood concentrates the boron in the saturated liquid that remains in the core. In addition, the volume of the SIT is still available for injection. Since the boron requirements are based on the average boron concentration of the total volume of the required SITs assuming a single failure. the consequences are less severe than they would be if a SIT were not available for injection. Thus, 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> is allowed to return the boron concentration to within limits.
/cM /nge~~ C a5 net po.vgpapQ (continued)
PALO VERDE UNITS 1,2,3 B 3.5.2-6 REVISION P'
INSERT C ITS BASES B 3.5.2 ACTION A.1 If one of the required SITs is inoperable due to the inability to verify level or pressure, the SIT must be returned to operable status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. Section 7.4 of NUREG-1366 (Ref. 4) discusses surveillance requirements in technical specifications for the instrument channels used in the measurement of water level and pressure in SITs. The following statement is made in Section 7.4 of NUREG-1 366 (Ref. 4):
"The combination of redundant level and pressure instrumentation [for any single SIT] may provide sufficient information so that it may not be worthwhile to always attempt to correct drift associated with one instrument [with resulting radiation exposures during entry into containment] if there were sufficient time to repair one in the event that a second one became inoperable. Because these instruments do not initiate a safety action, it is reasonable to extend the allowable outage for them. The [NRC] staff, therefore, recommends that an additional condition be established for the specific case, where 'One accumulator
[SIT] is inoperable due to the inoperability of water level and pressure channels,'n which the completion time to restore the accumulator to operable status will be 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. While technically inoperable, the accumulator would be available to fulfillits safety function during this time and, thus, this change would have a negligible increase in risk."
SITs - Shutdown B 3.5.2 BASES
\
ACTIONS B.l Ov 4'. <m4~(<'o CC,le leVet ov p~<Zurp If one SIT is 'perable for a reason other than boron concentration. the SIT must be returned to OPERABLE status zf hours w>>n . In this Condition, the required contents of three S nnot be assumed to reach the core during a LOCA Due e severity of e conse uence ou a ccur in ese conditions, e 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> Comp ion Time to open valve, remove er to the valv . or restore the pro r water volume nitrogen cover ressure ensures t ompt action wil e taken to ret the inoperable to OPERABLE status The Completio ime minimizes t potential fo xposure of the ant to a LOCA er thes conditi ns.
Actd In(erk y C.1 Qf ne.~
~yr Pl If the inoperability of the requi red SIT was discovered but not restored while the plant was within the applicability of specification 3.5.1. "SITs - Operating", the plant must be brought to a HODE in which the LCO does not apply. The time allowed for restoration in specification 3.5.2 is adequate may not be duplicated, for the same condition, when in,
'nd specification 3.5.2, "SITs - Shutdown".
If the required SIT cannot be restored to OPERABLE status within the associated Completion Time, the plant must be brought to a HODE in which the LCO does not apply.
To achieve this status, the plant must be brought to at least HODE 5 within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. The allowed Completion Time is reasonable, based on operating experience, to reach the required plant conditions in an orderly manner and without challenging plant systems.
D.1 If more than one of the required SITs is inoperable, the unit is in a condition outside the accident analyses.
Therefore, LCO 3.0.3 must be entered immediately.
(continued)
PALO VERDE UNITS 1.2,3 B 3.5.2-7 REVISION P'
INSERT D ITS BASES B 3.5.2 ACTION B.1 C
CE NPSD-994 (Ref. 5) provides a series of deterministic and probabilistic findings that support 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> as being either "risk beneficial" or "risk neutral" in comparison to shorter periods for restoring the SIT to OPERABLE status. CE NPSD-994 (Ref. 5) discusses best-estimate analysis for a typical PWR that confirmed that, during large-break LOCA scenarios, core melt can be prevented by either operation of one low pressure safety injection (LPSI) pump or the operation of one high pressure safety injection (HPSI) pump and a single SIT.
CE NPSD-994 (Ref. 5) also discusses plant-specific probabilistic analysis that evaluated the risk-impact of the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> recovery period in comparison to shorter recovery periods.
SITs -Shutdown 8 3.5.2 BASES SURVEILLANCE SR 3.5.2.4 (continued)
REQUIREMENTS because the water contained in the RWT is within the SIT boron concentration requirements. This is consistent with the recommendations of NUREG-1366 (Ref. 4).
SR 3.5.2.5 Verification every 31 days that power is removed from each required SIT isolation valve operator when the pressurizer pressure is ~ 1500 psia ensures that an active failure could not result in the undetected closure of a SIT motor operated isolation valve. If this were to occur, two less than the requi red SITs would be avai lable for injection, given a single failure coincident with a LOCA.
Since installation and removal of power to the SIT isolation valve operators is conducted under administrative control, the 31 day Frequency was chosen to provide additional assurance that power is removed.
This SR allows power to be supplied to the motor operated isolation valves when pressurizer pressure is ( 1500 psia, thus allowing operational flexibility by avoiding unnecessary delays to manipulate the breakers during unit startups or shutdowns. Even with power supplied to the valves, inadvertent closure is prevented by the RCS pressure interlock associated with the valves. Should closure of a valve occur in spite of the inter lock, the SI signal provided to the valves would open a closed valve in the event of a LOCA.
REFERENCES 1. IEEE Standard 279-1971.
- 2. 10 CFR 50.46.
- 3. UFSAR. Chapter 15.
I~peva~en4s 4 Teg<(gg (
- 4. NUREG-1366. December 1992. ~ '.<<~+~~ S~rv6 ([~g~
W~Lf+ ~q ~+ I ~
E+6 go'ink App ~tchg i'ant @(orf 4v
~"J~<+~ T <<4 go~/<>< < ~ -
eg PALO VERDE UNITS 1.2,3 B 3.5.2-9 REVISION P I
0 T t