ML20154A107
| ML20154A107 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 08/30/1988 |
| From: | PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | |
| Shared Package | |
| ML20154A090 | List: |
| References | |
| NUDOCS 8809120061 | |
| Download: ML20154A107 (36) | |
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i TABLE 3.2.B i
i INS 1PUMENTATION THAT INITIATES OR CONTROLS THE CORE AND CONTAlf38CNT
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j COOLING SYSTEMS Minteum No.
l Cf Operable Number of-Instru-Instysment Trip Function Trip Level Setting ment Channels Pro-Remarks I
Channels Per vided by Design
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frip System (1)
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2 Core Spray Pusc.
6 +/- I sec.
4 timers All pumps-loss of offsite power only i
j Start Timer 13 sec. +/-M of setting 2 timers A & C pumps-offsite power available i
23 sec. +/-7% of setting 2 timers E & D pumps-offsite power available i
l 2
LPCI Pump Start Timer 2 sec. +/-7% of setting 4 timers LPCI pumps A & E (Four pumps) 8 sec. +/-7% of setting 4 timers LPCI pumps C & D
[
1 ADS Actuation Timer 90 </= t </= 120 2 timers In conjunction with
- c' seconds low Reactor Water Level, High Drywell Pressure and LPCI or Core Spray Pump running interlock, initiates ADS.
2 ADS Bypass Timer
- 8 </- t </- 10 4 timers In conjunction witt.
minutes low r actor water level, bypas,es nigh dry ell pressure initiation of ADS.
2 RHR (LPCI) Pump 50 +/- 10 psig 4 channels Defers ADS actuat:1on Discr,arge Preset e pending confirmation of Inter 1cck Low Pressure Core Cooling syster operation (LPCI Pump running interlock).,
2 Core Spray P> imp 185 4/- 10 psig 4 channels Defers ADS actuaticr.
Discharge Pressu'e pending confirmation of Interlock Low Prcssure Core cooling system operation-(Core Spray Pump runnig interlock).
- t'ffective when modification associated with this amendment is complete.
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TABLE 3.2.B INSTRUNENTATION THAT INITIATES f.,R CONTROL 3 Tif5 CORE AND CONTAINMENT COOLING SYSTEMS Minimum tio, j
Of Operable Number of In.tru-Instrument Trip function Trip Level Setting ment Channels Pro-Remarks l
Channels Per vided by Design Trip System (I)
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2 Ccore Spray Pump 6 +/- I sec.
4 timers All pumps-toss of offsite power only Start Tim =r 13 sec. +/-7: of setting 2 timers A & C smps-offsite power available
?3 sec. +/- M of setting 2 timers B & D pumps-offsite power avaliable 4
2 LPCI Pung Start Timer 2 sec. +/-7% of setting 4 f.iners LPCI pumps A & F, l
j (four pumps) 8 sec. 4/-7% of setting 4 timers LPCI pumps C & D I
l 1
ADS Actuatior. Timer 90 </= t </= 120 2 timers Ir> conjunction with seconos low Feactor Water Level, High Drywel? Pressure o.
p and LPCI o'r Core Spray Pump running interlock, initiatti ADS.
2 ADS Bypass Timer 6 </= t </= 10 4 timers 10 conjunction with j
r-inutes
" u reactor water level, oynasses high drywell pressure irtitiation of ADS.
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2 RHR (LPCI) Pump 50 +/- 10 psig 4 channels Defers ADS actuation Discharge Pressure pending confirmation of a
j Interlock Low Pressure Coe2 Cooling system operation (LPCI Pump rening interlock).
i 2
Core Spray Ptap 185 +/- IC, psie, 4 channels Defers ADS actuation Discharge Pressure pending can'irmation of Interlock Low Pressure Core coolirg l
system operation (Cora spray Pump running interlocQ.
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I TABLE 3.2.8 (CONTINUED)
IG5TRUMENTATION AT INIll ATES OR CONTROL'~= THE CORE AND CONTAINMENT 3
COOLING SYSTEMS iNinic.m No.
~
Of Operable Number af "nstr:snen:
Trip Functice.
Trip Level Setting Instrument Remarks Char ~iels Per Cnannels Trip System (1)
Provided by Design 2 per 4KV Emerger cy 60%(15%) of rated I. Trips emergency Bus Tran:, form 2r Volt ege..
Test at transfer feed Undervoltage (IAV) zero volts in 1.8 to 4hV emer-(inverse time-secc-ids (110%),
gen':y bus.
voltage) 2.7est transfer permiss1<e.
2 per 4kV Emercency Trans-89% of rated voltage Bus former Degraded 3 30% o' setting 0
voltage (27N)
!3702 sclt0 i 11 volts)
(Instantaneous) 60 second
- 1. Trips erirgency (25%) tire delay.
transformer feed to 4kV emergency bus.
- 2. Fast transfer permissive.
9 second (17%)
- 1. Trips emergency l
time delay transformer feed to 4kV emer-gency bus.
- 2. Fast transfer permissive.
- 3. Safety injec-tion signal required.
j
PBAPS 1.2 UASES (Cont'd.)
The recirculation pump trip has been added at the suggestion of ACRS as a means of limiting the consequences of the unlikely becurrence of a failure to scram during an anticipated transient.
The response of the plant to this postulated event is within the envelope of study events given in General Electric Company Topical Report, NEDO-10439, dated March, 1971.
In the event of a loss of the reactor building ventilation system, radiant heating in the vicinity of the main steam lines raises the ambient temperature above 200 degrees F.
Restoration of the main steam line tunnel ventilation flow momentarily exposes the temperature sensors to high gas temperatures.
The momentary temperature increase can cause an unnecessary main steam line isolation and reactor scram.
Permission is provided to increase the temperature trip eetpoint to 250 degrees r for 30 minutes during restoration of ventilation system to avoid an unnecessary plant transient.
The Emergency Aux. Power Source Degraded Voltage trip function prevents damage to safety-related equipment in ?.he event of a sustained period of low voltage.
The voltage suppi ' to each l
of the 4kV buses will be monitored by undervoltLge relaying.
With a degraded voltage condition on thF cff-site source, the undervoltage sensing relays operate to 16iltiate a timing sequence.
The timing sequence provides constant and inverse time voltage characteristics.
Degraded voltage protection includes (1) An instantaneous relay (27N) inJtiated at 89% voltage witich initiates a 60-second tjee Jalay relay and a 9 second time delay relay.
The 9-second time delay relay requires the presence of a safety injection signal to initiate tre.npfera ( 7. ) Ati inverse time voltage relay (CV-6) initiated at 871 voltage with a maximum 60 second delay and operates at 70% voltage in 30 seconds; and (3)
An inverse time voltage relay (IAV) initiated at approximately 60s voltage and operates at 1.e seconds at zero volts.
When the tim'.ng sequFnce is completed, the corresponding 4kV emergency circuit breakers are tripped and tha emergency buses are tiansferred to the a? ternate cource.
The 60-second timing sequences were selected to prewar. unnecessary transfeea during motor starts and to allow the automatic tapchanger on the startup t ransformer to respond to the voltage condition:
The 9-(
sncond timir.g sequence im necessary to prevent separation of the emergency buses from tisa off-site sourcs during motor starting transients, yet sel)1 be contained within the timo envelope in PS%R Table 8.5.1,
-93a-
Supplcm7ntal Information On July 1, 1988, PECo representatives met with members of the NRC staff to discuss the results of the revised voltage regulation study and the proposed Technical Specification changeo.
The NRC staff identified items which required a PECo response.
These items along with their responses are stated below.
Item 1:
Model Validation To verify the validity of the revised voltage regulation study, a model validation test will be performed in accordance with PSB-1.
Actual measurements of auxiliary system parameters (volts, watts and vars) at selected system locations will be made and compared with the calculated values assumed in the study.
The model validation test trill cover two test sequences or sets of test cases, one Nith No. 2 startup cource (82 sturtup transformer) and the other with No. 3 stattup source (#343 startup transformer) supplying power to the auxiliary system.
The test will include the recording o."
transformer tap settings, recording of voltage and loading (watt and ver) of selected buses, as well as equipment terminal voltages.
The test will address bo'.h steady state and larger motor starting trench
.t conditions.
The approximate minimum loading on the startup transformer will be 15MVA..
Item 2:
Operation below Emergency Rating The original voitage regulation study assumed an emergency rating of 0.95 pu.
To address the NRC concern as to whether either of the two startup sources had ever reached this level, the opecating history of the No. 2 startup source (#2 startup transformer) and the No. 3 startup source (#343 startup transformer) were researched.
The normal voltage range for the Peach Bottom tap (#2 startup) 220-08 line is 0.975 pu (224.3kV) to 1.043 pu (239.9kV) and the emergency voltage range is 0.941 pu (216.4kV) to 1.054 pu (24/.4kV).
The normal voltage range for Peach Bottom 230kV (#343 startup) is 0.975 pu (224.3kV) to 1.043 pu (239.9kV) and the emergency voltage range is 0.947 pu (217.8kV) to 1.054 pu (242.4 kV).
The latest voltage regulation study considered both maximum and minimum emergency voltage levels and used a lower value of 0.934 (214.8 kV) for the minimum emergency voltage level in the analysis assuraing the modifications are completed.
The source supply for the #343 startup transtormer is i
the 220-34 line, a 230kV transmiscion line at the Peach Bottom 230kV substation.
To the best of our knowledge, the lowest voltage present on Peach Bottom #343 Startup Transformer occurred at 2:29 p.m. on June 1, 1987 when 0.947 pu or 218kV was present.
The voltage was below 0.95 pu for one to two hours that day.
This Peach liottom 230kV voltage is a calculated value based on monitored voltage and power flows at Newlinville.9ubstation.
2
Newlinville is at the other end of 220-34 line from Peach Bottom.
Direct monitoring of voltages at Peach Bottom 230kV was out of service on June 1, due to the outage of Peach Bottom fl 500-230kV transformer.
Philadelphia Electric Co. does not retain complete documentation of system bus voltages.
PECo does record conditions each Honday and retains information for unusual or interesting operating conditions.
Also, PECo's energy control computer SAMAC alerts the system operators to low voltages.
Based on these sources of information, the only known incident of voltage below 0.95 pu is that of June 1, 1987.
Normally, the Peach Bottom 230kV bus is connected to the 500kV system through Peach Bottom #1 500-230kV transformer.
This provides a stiff supply, keeping voltages on Peach Bottom 230kV in line with voltages throughout that part of the 500kV system.
Only a general system emergency would cause voltages to drop to emergency levels.
The.cw voltage on June 1, 1987 was a result of abnormal offsite operating conditions.
From April 13, 1986 to October 14, 1987. Peach Bottom #1 transformer was out of service due to a fire and the subsequent replacement of the transformer.
During this time, the Peach Bottom 230kV bus was connected to the b.. tem by only the 220-34 line, a 33 mile line to Neilinville Substation.
Also connected to Peach Gottom 230kV bus are the 220-06 and 220-07 lines which are the only system connections for the Muddy Run Pumped Storage Hydroelectric Plant.
Therefore, for _ _ _.
the one and a half years that Peach Bottom #1 transformer was out of service, Peach Bottom 230kV voltage was dependent more on the operation of Muddy Run than on general system conditions.
During the transformer outage, Muddy Run operation was restricted because of low voltages.
In the pumping mode, no more than 6 out of 8 units were operated concurrently.
In the generating mode, all eight units could be operated under normal rated output of 880 MW.
On June 1, 1987, a full pond permitted Muddy Run to generate 956MW or 91 over rated output.
A full pond is only present on Monday as Muddy Run operates on a weekly t
basis.
This is the special operating condition that caused reactive power losses in 220-06, 220-07 and 220-34 lines to increase beyond the reactive power operating state of Muddy Run causing the low voltage on Peach Bottom 230kV bus.
Muddy Run has the flexibility of operation to control the Peach Bottom 230kV voltage.
Por example, if only seven units had been generating on June 1, 1987, the Peach Bottom 230kV voltage would have been greater than 0.95 pu.
The source supply for the #2 startup transformer is the 220-08 line. a 230kV tie line between Philadelphia Elect.ic Company and Baltimore Gas and Electric Co.
Unlike the #343 startup transformer, the #2 startup transformer is far from any source of voltage control.
Any low voltage would represent a general system emergency with low voltages throughout the Philadelphia Electric and Baltimore Gas and Electric systems.
There are no known incidents where the voltage on the Peach Bottom #2 startup transformer went below 0.95 pu.
4
Item 3:
Assurance of Emergency Rating Assumptio6 L
As stated in Item 2, the original voltage regulation study assumed an emergency rating of tha offsite power supplies to be 0.95 pu.
Because of the long term loss of the Peach Bottom
- 1 transformer due co a fire in the transformer, the revised voltage regulation study conservatively assumed an emergency rating of 0.934 pu.
It is not expected that this value will over occur.
While the PJM and PECo long term plans predict continued load growth, for the region and this growth will be offset by the completion of additional generating units, the plans do not i
project any need for additional substation tied to any of the lines that feed the Peach Bottom Area.
i An agreement will be made between the Load Dispatcher and Peach Botcom mar.agement to alert the Operations staff in anticipation of any abnormal grid conditions which would indicate that the 0.934 pu emergency rating assumption is inadequate.
Item 4:
Non-Technical Specification Modifications i
l The safety evaluations for the modifications involving the Emergency Service Water pumps, the Emergency Cooling Water pump, the RHR compartment coolers, the cooling towers and the diesci generator vent supply fans are attached.
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4 2880088750 SAFETY EVALUATION FOR M00 2568+
AUG 191988 PEACH BOTTOM ATOMIC POWER STATICt1 UNITS NO. 2 & 3 Revision 1 1
1.
SUBJECT:
This rnodification changes the time settings to start the Residual Heat Renoval (RHR) pums, and the Core Spray (CS) pums, for Units ib. 2 and 3 and the station ccrmen Emergency Service Water (ESW) and Emergency Cooling Water (ECW) pums upon receipt of a Loss of Coolant Accident (LOCA) signal, as described below jn part l
!!! of thin docunent.
Selection of the new time settings is ba'$d on the results of the j
voltage regulation study for the Peach r com Atcynic Pcwor Station (PBAPS*), Units No. 2 & 3 performed by Bechtel Power Corporation under modification 2123.
!!. CONCLUSION:
This modification:
a.
does affect safety related equipnent; b.
does not involve an unreviewed safety question; c.
does require a technical specification change; d.
does maintain the capability to safely shutdown the plant in the event of a fire; does require a license arnendnent or prior NRC approval; e.
f.
does not_ involve a significant hazards consideration.
!!!. DISCUSSION:
The present loading sequence for the RHR, CS, ESW, and ECW pums in the event of a LOCA, with offsite pcwer available, is as l
follows:
t = -3 seconds TrIpie Low Leve1 Is reached O second Initiation of LOCA signal 0 second Start RHR pums A G B 5 seconds Start RHR pums C C 0 10 seconds Start CS pums A, B, C & O 22 seconds Start ECW and ESW pums A C B In order to irmrove voltage regulation in the event of a LOCA vhlle operating frcan either a single or both offsite sources that are at their emergency voltage ratings, new time settings are required for the loading sequence for the core standby cooling, emergency service water, and energency cooling water systerre. The new time settings will maintain voltages sufficient to ensure safe operation of the RHR, CS, ESW, and ECW pums and associated loads.
Stfcty Evaluation for M00 2564 l** vision'1 2880088750 2
The rmdtfled loading sequence is as folicws:
In the event of a LOCA with offsite power available, the follcwing loading sequence takes place:
t = -3 seconds Triple Low Level is reached 0 second initiation of LOCA signal 2 seconds +/- 7% of setting Stort RHR pums A & B 8 secnnds +/- 7% of setting Start RHR purms C & D 13 seconds +/- 7% of setting Start CS pums A & C 23 seconds +/- 7% of setting Start CS pums B & D l
36.econds +/- 7% of setting Start ESW pums A & B and ECW pum.
l s
There are no changes to the existing RNt and CS puno Initiation sequence in the event of a LOCA coincident with a Loss of Offsite Pcwer. The existing diesel loading sequence for the RHR and CS pums remains unchanged. The new initlation timer setting of 36 l
seconds for the ESW and ECW pums will t's in effect regardless of the power source.
I The increased ESW and ECW tirne delays will not Irmact other diesel generator loads that are operating during ESW and ECW Initiation. The loads that operate closest to the new ESW/ECW Initiation at 49 seconds (LOCA concurrent with loss of offsite l
power requires an additional 13 seconds for the diesel generators to ccrne up to speed and close their breakers), are the reactor recirculation discharge valves which begin closing at 27 seconds (design basis suction line break). These valves can operate as low as 80% of their rated voltage. Based on the diesel generator loading measurements perfonned at Peach Bottom and the design of the recirculation discharge valves, the transient effects caused by delayed ESW/ ECW Initiation will not cause the discharge valve motor operator voltage to drop below an acceptable voltage level.
l After Irmlementation of this rmdification, the RHR, CS, ECW, and ESW pums and associated loads will start and c.ccelerate within the allcwable motor terminsi voltages without causing excessive voltage drop on the associated 4.16kV and 480V buses.
The General Electric Appendix K LOCA analysis and the Supplemental l
Reload Licensing Sthmittal were used to determine boundlag allcwable starting times for the RHR (LPCI) and CS pums. The new tirrer values Irmosed by this rnodification fall within the limiting starting tirres analyzed by the Appendix K LOCA analysis, and thus, no accident analyses are affected.
' afety Evaluation for 100 2564 S
Ptg3 3 of 11 2880088750 Revision 1 There are two elements that define success for the CS system; pure ready for rated flow and injection valve open to permit full ficw. Purp ready for rated flow ls defined as the purp being at design full speed (wet). Full flew through the injection valve requires the valve to be full open. There are two conditions required to support valve opening in a Ilmiting case flow path; reactor pressure is at the low end of its Icw pressure pennissive (400-500 psig) and power is available at the valve operator.
In the limiting ECCS scenario for CS as analyzed by GE's Appendix K analysis (100% break in the reactor recirculation discharge line),
the Icw pressure permissive occurs 47 seconds after reaching triple low level; power to the valves nust be established prior to this time. Although design characteristics shcw that a gate valve at half stroke passes nest of its rated flow, the Appendix K analysis does not assune Core Spray flow into the vessel until the CS Injection valve is at its full open stroke, which requires 12 seconds to traverse from full close. Therefore, per the Appendix K analysis, the earliest that the CS Injection valve can be opened is 59 seconds after triple Icw level, and the puros nust be ready for full flow prior to this time.
The series of events contributing to the establishnent of the puros ready for rated ficw are the sensor times for detection of the LOCA (3 seconds), the time for peer to be made available at the emergency bus (this time is zero if offsite power is avail-able), the time for power to be made available to the purp notor (ECCS purp notor timing relay setting) and puro motor acceleration time (dependant upon notor terminal voltage) which, at worst case voltage, is 6.8 seconds for the A and C CS purps and 8.1 seccnds l
for the B and 0 CS puros.
Both times assune an open flow path, which is nore limiting with respect to acceleration time than a closed flow path.
Per the Appendix K analysis, the tine available after triple Icw level to start and accelerate the CS puros frcm the offsite sources is 59 seconds. Taking into account the above equiprent delays, the resulting analyzed limit for the ECCS CS timer is 47.9 seconds. Thus, although the 13 and 23 second timer l
settings proposed by this nodlfication reduce the existing design margin relative to puTos being ready for rated flow, they fall within the limit analyzed by GE.
Similarly, there are three elements that define success for the Icw pressure coolant injection (LPCI) node of the RHR system; puTp ready for rated ficw, injection valve open to permit full ficw (full stroke is required to admit flow) and full closure of the recirculation discharge valve. Per the Appendix K analysis, the Ilmiting time for the limiting LPCI scenario (100% break in the reactor recirculation suction line) is 57 seccods which consists of the time to reach the low pressure permissive to close the reactor recirculation discharge valve (30 seconds after reaching triple low level to reach 200-250 psig) plus the full stroke closure time of the recirculation discharge valve (27 seconds).
The series of events for the RHR purps ready for rated flow are Identical to the series of events for the CS puros except
Safety Evaluation for M00 2564 Pags 4 of 11 Revision 1 2880088750 that the acceleration time for the ASB RHR pmps is 2.8 seconds and the CSD pmp acceleration time is 3.1 seconds at the worst case voltcge level and pwping into an cpen ficw path. Taking into account the sensor and acceleration delays, the resulting analyzed limit for the ECCS LPCI timer is 50.9 seconds. Thus, l
although the 2 and 8 second timer settings proposed by this redlfication reduce the existing design margin relative to pwos being ready for rated flow, they fall within the Ilmit analyzed by GE.
The limiting design function for the Emergency Service Water System is the delivery of cooling water to the emergency di'esel generators. The present ESW Initiation celay is 22 seconds.
After Inplementrtion of this mod, ESW will Initt ste in 36 seconds with offsite prar available. ESW will Initiate in 49 seconds when operaticJ off of the diesel generators.
The diesel manufacturer has tested the PBAPS diesel design and has shown that the diesels can run without cooling water for up to three minutes, as identified in UFSAR Section 8.5.3.
- Also, Limerick Generating Station enploys emergency diesel generators that are the same rmdel as those used at PBAPS. The existing ESW pwp delay at Limerick is ncminally 55 seconds for a diesel ' start with offsite power available; 6 seconds longer than the PBAPS longest delay time of 49 seconds. No diesel failure has ever occurred at Limerick due to a lack of emergency service water.
Based on the diesel design and the experience at Limerick, I
delaying the PBAPS ESW Initiation an additional 14 seconds will l
not adversely affect diesel operation.
The ECW pmp is designed as a backup to the ESW pmps and is initiated at the same time as the ESW pwos. Whenever the ESW pwps reach rated flow and pressure, the ECW pwp is autcmatically tripped off. Since the ECW pm p acts as a backup to the ESW system, delaying ECW Initiation an additional 14 secends will not l
have an adverse affect upon the plant.
The time settings have been selected to optimize the voltage regulation within the limits for core coolant delivery established by the Appendix K analysis while also minimizing the changes to the existing ECCS Initiation sequence. The overall benefit of this modification is to ensure that adequate voltage is provided for starting and accelerating the ECCS pmp mators and associated loads in the event of a design basis accident while operating with either a single or both offsite sources that are at their emer-gency voltage ratings.
All equipnent supplied by this rmdtfication Is safety related.
The only equipnent supplied is new and replacement time delay control relays that will be located in existing safety-related panels. The panels are located in a mild environrent.
The centrol relays provided will equal or exceed the ratings of the existing relays and meet the applicable design requirenents for such relays, including, but not limited to envirormental quallff-cation, seism!c qualification and quality assurance.
Sofcty Evcluation for M00 2564 DisM'1 2880088750 No additional loads are placed on the station power syste:n by this modification. The RHR pums and CS pums are presently equipped with either auxillery or time delay control relays.
The present time delay relay:. for the B and D CS punps, and the A and B RHR pesrps nust be repler:ed to acccmodate the new time settings. All control relayr are 125 VDC. The pcwer consunption of the replacement relays is the same as she existing relays, six (6) watts each.
I This modification will maintain the capability to safely shut dcm the plant in the event of a fire, because no cables or condults are added in any fire zones, therefore, this nodification has no effect on fire protection capability.
This tr.odification does not involve radwaste system. Therefore, the guidance provided in IE Circular 80-18 is not appIIcable.
The design of this nodification has no inpact on ALARA considerations.
UFSAR Sections 6.4.3, 6.4.4, 6.5.3.3, 6.5 3.4, 7.4.3.4, 7.4.3.5, 8.5.1, 8.5.2, 8.5.3, 8.5.4, 10.9, 10.24, 14.5, 14.6, and table 8.5.1 have been reviewed for this nudification. Sections 7.4.3.4.2 and 7.4.3.5.2 as well as figures 7.4.5a, 7.4.7a, and 10.24.1 and Table 8.5.1 nust be revised to show the new Core Spray, RHR, ESW and ECW pum delays.
I PBAPS Technical Specification Sections 3.2.B, 3.5 and 3.9 have been reviewed. Page 67 of. Table 3.2.B will be revised to indicate the new start times and tolerances for the RHR and CS puros. ESW and ECW Initiation times are not identified in the Technical Specifications.
IV.
10CFR50.59_CtW r,ES. TESTS. Ato EXPERIMENTS:
1.
Inplementation of this nodification at Peach Bottcm Atcrnic Pcwer Station Units 2 & 3 will not; Increase,the probability of occurrence or the conse-a.
ovence of an accident or malfmetton of equipment Irrportant to safety as previously evaluated in the FSAR. This nudification affects the start times for equiprmnt provided to mitigate the consequences of a LOCA. The times assuned in the Appendix K LOCA analysis for availability of LPCI (57 seconds) and CS (59 seconds) are not affected by the new start times for the RHR (2 seconds ASB, 8 seconds CSD), CS (13 seconds ASC, 23 seconds BSD), ESW, and ECW pums (36 seconds). The pum start timer changes have no affect on the probability of occurrence of an eccident.
S:fcty Evaluation for M00 2564 Page 6 of 11 2880088750 Revision 1 d
i The control relays being added and replaced are the same as those presently in service except for their available time delay.
Thus the failure effects of these relays on the ECCS systems have not changed.
r Failure of a relay can only affect one redundant train of equiprent. The current design tolerates failure of a redundant train.
2 There are no limiting transients identified in Chapter 14 of the UFSAR that involves the RHR or CS systems.
3 Since the CS and RfR system response times fall wjthin the limiting response times analyzed by the Appendix K analysis, the Design Basis Accident Analysis contained in Chapter 14 of the UFSAR is not Irmacted. Therefore, the consequences of an accident are not increased.
i f
b.
Create the possibility for an accident or malfunction i
I of a different type than any previously evaluated in the PSAR. This nodification adds or replaces time delay relays that control the start times for the RHR, CS, ESW, and ECW pums. These relays are Identical to the relays presently in service except for the time i
delay range, therefore, no new fallure effects are introduced into the systems.
i There are no limiting transients concerning RHR or CS systems in chapter 14 of the UFSAR. Since the CS and RtR systc7 response times fall w! thin the Ilmiting response times analyzed by the Appendix K analysis, the l
Design Basis Accident Ar.alysis contained in Chapter 14 of the UFSAR is not Irmacted. Therefore, the conse-quences of an accident are not increased. Failure of a L
j relay ca, only affect one redtndant train of equignent.
The current design tolerates failure of a redundant j
train.
i The relays do not Irmact the existing qualification of the panels in which they are located. The new CS, RHR,
[
ESW and ECW start times will not Irmact LOCA environ-j mental parameters used for envircrvnental qualification 7
purposes.
i L
Reduce the margin of safety as defined in the basis of c.
any Technical Specifications. The Initiation times for
[
the RHR and CS pums will be increased frcm the values l
Identified in the PSAPS Technical Specifications. The I
i new timer values were chosen to minimize delay In the ECCS Initiation secuence yet provide Irmroved starting i
voltage for each pum trotor. The new initiation times are enveloped by the ECCS response times assuned in the Appendix K LOCA analysts of record as referenced in the Supplemental Reload Licensing Sutmittal for PBAPS Units 2 and 3 for Reloads 7 and 8 respectively.
i
5:f s y Evaluation for MOD 2564 Page 7 of 11 Revision 1 2880088750 Per 10CFR 50.46, the Ilmiting safaty parameters in the event of a Design Basis LOCA correspond to fuel Integrity (i.e., peak cladding terrperature, zirconfun water hydrogen generation, cladding oxidation, and coolable gecrnetry).
Successful ECCS response prevents or Ilmits degradation of these fuel parameters. The Appendix K LOCA analysis has utilized limiting design basis ECCS response times (57 seconds for LPC:, 59 seconds for CS) to dertonstrate successfiti ECCS per-fonnance.
1 Successful ECCS perfonnanco is defined by injectlon of rated flow into the reactor vessel.
In order for the Core Spray system to meet this goal, the CS pups nust I
be ready for rated flow and its injection valve mus*, be i
open to pass rated flow. Opening of the injection valve is dependent on a low reactor pressure pennissive which, i
according to the Appendix K analysis, takes place 47 seconds af ter reaching triple Icw level. An additional 12 seconds is required to allcw the injection valve.to r
open to full stroke to pennit flow per the assunptions in GE's Appendix K analysis. This is a conservative assuretton since the design characteristics of a gate valve, Ilke the CS Injection valve, pennit passage ot' trost of its rated ficw at half stroke. With the new timer settings, the CS pums will havs accelerated to rated speed befnre the injection valves receive their pennissives to open. Considering the times for detec-tion of the LOCA and acceleration of the purp rrotors in f
an open system, the A and C CS pums will be at rated speed in 22.8 seconds and the B and D CG pums will be at rated speed by 34.1 seconds. Puro acceleration time for an open system is trore limiting than the time achievable In a closed system. Therefore, although l
Installing new CS Initiation timer settings will reduce the existing design margin relative to puros beinc ready for rated flow, they will not result in a l
reduction in the margin of safety for core coolant i
delivery.
In order for the RHR system to achievo its cooling objective, the RfR purps trat be ready for rated ficw, the pum's injection valve aust be open to pass rated ficw (assuned to be full stroke), and the reactor recirculation discharge valve trust fully close. Closure I
j I
of the reactor recirculation discharge valve is dependent on a Icw pressure pennissive which, according to the Appendix K analysis, takes place 30 seconds after i
reaching triple Icw level. An additional 27 seconds is I
required for the full stroke closure of the valve.
)
Taking into consideration the new timer settings, and the times for the detection of the LOCA and acceleration of the puro motors into an open system,'the A and B RHR l
I i
50foty Evaluation for M00 2564 l
l
%#si 2880088750 l
pums will be at full speed within 7.8 seconds and the C and D RHR pums will be at rated speed by 14.1 seconds.
4 Open system pum acceleration time Is more limiting than a closed system. Thus, all four RHR pums will be available for full flow 42.9 seconds before the reactor l
T recirculation discharge valve closes. Therefore, although Installing new RHR Initiation timer settings will reduce the existing design margin relative to pums l
being ready for rated flow, they will not result in a reduction in the margin of safety for core coolant I
I delivery.
This nodification does not affect any limiting safety system setpoints for level or pressure as identified in the Technical Specifications.
j 2.
The applicable sections of the Technical Specifications are
[
3.2.5, 3.5, 3.0 and the associated bases. Page 67 of Table l
l 3.2.81s affected by this nodification, and needs to be revised to show the new pum relay timer settings as l
t j
follows:
2 seconds 4/- 7% of setting Start A & 8 RHR pums j
8 seconds +/- 7% of setting Start C S D RHR pums r
i 13 seconds +/- 7% of setting Start A S C Core Spray pums i
11 23 seconds +/- 7% of setting Start B S D Core Spray pums l
3.
An amendment to the operating IIcense is required to change f
i the Technical Specification start times and tolerances for the RHR and CS pums found on page 67, Table 3.2.5.
(
i i
V.
10CFR$0.92 SIGNIFICANT HAZNtDS DETERM!?MTION:
e b
l This Technical Specification change does not involve any signiff-cant hazards considerations based on the guidance provided by the NRC in Generic Letter 86-03, and in the March 6, 1986, Federal Register (51 FR 7750). One of the exarmies (vi) fomd in 51 FR 7750 concerns actions Involving no significant hazards considera-tions is:
"A change which either may result in sone Increase to the probability or consequences of a previously analyzed accident j
or may reduce In sane way a safety margin but where the results of the change are clearly within all acceptable criteria with respect to the system or cwvarent specifled in tho Standard Review Plan."
i Of all the examles identified in 51 FR 7750, exarmte vi represents i
the closest correlation to this proposed Technical Specification change. This example, hcwever, is not apptIcable for this mod!-
fication since the proposed change in RHR ard CS pum initiation i
l times will not reduce a margin of safety or increase the proba-bility or consequences of an accident. The om pum initiation times will have no affect on final coolant availab!11ty to the
' S:fcty Evaluation for M00 2564 Ptg3 9 of 11 2880088750 Revision 1 vessel in the event of a LOCA. As detennined by the Appendix K LOCA analysts, final RHR and Core Spray injection into the vessel is dependent on Icw reactor pressure permissives which occur after the puros have accelerated to their rated speed based on their new start times.
As a result of this rrodification, the operation of the plant:
1.
does not involve a significant increase in the probability or consequences of ar, accident previously evaluated. This Technical Specification change effects the start times,of equipnent prov!ded to mitigate the consequences of a LOCA.
The times assured in the General Electric Appendix K LOCA analysis for availability of LPCI (57 seconds) and CS (59 seconds) are rut affected by the new start timos of the RHR (2 seconds ACB, 8 seconds CCD), and CS (13 seconds ACC, 23 l
seconds B&D) purr *. The new and replacanent relays are identical to those currently Installed except for their available time delay, and therefore do rot introduce any new failure effects into the systems. The changes in timing.
reduce the prcbability of equipment malfunction due to inade-quate bus voltago. The puTo start timer changes have no affect on the probability of occurrence of an accident.
There are no Ilmiting transients Identified in chapter 14 of the UFSAR that involves the RHR or CS systans.
Since the CS and RHR system response tirres fall within the Ilmiting response times analyzed by the Appendix K analysis, the Design Basis Accident Analysis centained in e,hapter 14 of the UFSAR is not irreacted.
2.
does not create the possibility of a new or different kind of accident fecm any accident previcusly evaluated. This Technical Specification change affects the start tirnes of equipment provided to mitigate the consequences of a LOCA.
Relays that determine the start times for the RHR, and CS putps will be added, adjusted or replaced. No new failure effects are Introduced by the new and replacement relays since they are identical to those presently Installed except for their available time delay. Failure of one of these relays can only affect one redundant train of equipmnt. The current design tolerates failure of one redmdant train.
3.
does not involve a significant redu:tico in a trargin of safety.
This rrodification only relates to the trorgin of safety for mitigatico of a LOCA. The tw CS and RHR initla-tion tirrus introduced by this nudir'ication will reduce the probability of Irtproper operatico of the RHR and CS puTps and associated equiprent due to Icw voltage, and will not impact ECCS availability as defined by GE's Appendix K LOCA analysis.
The prirrory fmetton of ECCS systems is to orevent or Ilmit degradation of fuel parareters (i.e. peak cladding tamera-
Safety Evcluation for H00 2564 Page 10 of 11 Revision 2880088750 ture, ciudding oxidation, coolable gecrretry, hydrogen generation) in the event of a LOCA. The Appendix K LOCA analysis has analyzed limiting ECCS response tinus (57 seconds for RHR, 59 seconds for CS) to ensure successful ECCS perfonronce.
Successful ECCS perfonronce is defined by injection of rated flow into the reactor vessel.
In order for the CS system to nwet this goal, the CS pums trust be ready for rated ficw, and, por Appendix K assumtlens, its injection valve nust be full open. The CS system nust receive a Icw reactor pressure perinissive to open its injection valve, which, according to the Appendix K analysis, takes place 47 seconds after reaching triple Icw level. /c additional 12 seconds is required to allcw full stroke opening of the valve which, per Appendix K assurptions, is required to pass full ficw. The Appendix K analysis assures no CS ficw into the vessel untti the CS Injection valve is full open. This is a conservative assumtion since the design characteristics of a gate valve, such as the CS Injection valve, allcw passage of nest of Its rated (Icw at half stroke. Therefore, the Appendix K analyzed response time for Core Spray is 59 seconds.
Accounting for the new initiaticn timor settings, and the tines for detecting the LOCA and accelerating the pum trotors, the A and C CS pums will be up to full speed within 22.8 seconds and the B and 0 CS pums will be up to speed within 34.1 seccods, assuning worst case voltage conditions and an open ficw path. Thus, all four CS pums will be ready for rated ficw 24.9 seconds before the systan's injection l
valve opening at 59 seccnds.
Before the RHR syston can inject coolant into the vessel, it too nust allcw its injection valve to open to full stroke per Appendix K assumtions, and, in addition, allow the reactor recirculation dircharge valve to fully close. Closure of tne recirculatloc discharge valvo is dependent on a Icw reactor pressure pennissive which occurs 30 seconds af ter reaching triple icw level as analyzed In Appendix K.
An additional 27 seconds is required to fully close the valve, reaulting in a required RHR response tine of 57 seconds.
/< counting for the new Ir tlation tiner settings, and the tines for detecting the LCCA and accelerating the pum trotors, the A and B RHR will be up to speed within 7.8 l
seconds and the C and 0 RHR pums will be up to speed within 14.1 seccods, assuning worst case voltage conditions and an l
open ficw path. Thus all four RHR pums will be ready for rated ficw 42.9 seconds before the 57 second analyzed RHR l
response tine Therefore, it is ccncluded that this Technical Specification l
change does not involve any significant hazards considerations.
S:fcty Evcluation for M00 2564 Page 11 of 11
"*" " 2 2880088750 VI. APPROVALS:
.Y[ [
Oate S-/@f8 Prepared By Responsible Engineer M 3L.
Date N
Lead lon (Branch Head or Section Head)
Date 8(16}60, 9
Ldw--
MNon-Lead SectIon {(Branch Fead or Sect. Head) k 'b '
Date Non-Lead [edtiongBranch Head or Sect. Head)
Date '
Y $V N*
~
tbn-Lead Section (Branch Head or Sect. Head)
' /
8,[M8 8'-
b [ Z />v> A Octe Reviewed By (Independent Reviewer)
Ok Date
%creaVf, Envitorrnental Sect. Head
~
i MGW/ lam /08188801 copy to:
L. B. Pyrlh E. P. ftKeown J. M. Pratt R. J. Lees J. F. Franz J. T. Robb j
G. A. Hmge r,
W. M. Alden J. F. O'Rourke j
W. W. Bcwers J. B. itLnughlin R. D. Walker W. J. Boyer A. C. Chan M. J. Leahy G. J. Beck D. A. Torone W. J. M!ndick R. J. Scholz J. K. Davenport DAC (NG-8) Occtype 565 A. J. Marie M. G. Wlwel T. E. Shanren 1
i 1
SAFETY EVALUATION FOR MODIFICATION 2580 PEACH EOTTCM ATCMIC POWER STATION UNITS 2 & 3 File:
j I.
SUBJECT j
s The Voltage Regulation study of Peach Bottom Atomic Power Station Units 2 &
3, undertaken to address the concerns that surf aced fecm the Millstone study concludec enat in the event of a LOCA at the plant, Cooling Tower loads be shed by the LCCA signal to improve voltages on 13.8 kV Unit Auxiliary buses as well as 4.14kV Emergency Auxiliary buses.
The cooling tower loats are non-safety related and are fed from one of the two off-site power sources.
II.
CCNCLUSION
,t This modification I
a.
does not affect sa f e ty i' a ted equipment ;
{
b.
coes not involve an unreviewed safety question; c.
does not require a te chni ca l specification change; I
d.
caos maintain the capability to safely shut down ene plant in the event of a fire; e.
does not require a license amendment or prior i
approval of tie Nuclear Regulatory Commission; 4
f.
do_es not involve significant hazards consideration.
III.
DISCUSSION At Psach Bottem, there are five mechanical draf t cooling towers (A, B,
C, D and E) which maintain the temperature of the water dischacged to the river within the environ-mental limits.
Cooling towers A, B and C each have one 5000HP pump and eleven 200HP cooliag fans.
Cooling towers D ano E eacn have one 7000HP pump and fourteen 250HP cooling fans.
All cooling tower pumps and fans are non-safety related and are f ed f rom either of the two of f-site pos r sources.
Presently, ecoling tower pumps and fans are shed on a unit trip so that the unit auxiliary buses can be picked
{
up by the off-site source without overburdening it.
In this modificativ. LOCA signals f ecm either Unit 2 or Unit 3 are used to energize the cooling tower load shedding relays 386X3A and 386X3B located in Turcine-Generator relay control panel 20C228.
Page 1 of 5 Rev.[2 MM RS16 (009)
- I9/*3 m
.s.
. - _. - -. -..- - ~. --
Scfoty Evaluation for Modification 2580 The LOCA signals are taken frem G.E.
NSSS engineered safeguard system control panels.
In Und*
2, control panel 20C32 provides Divisioa A LOCA s ig ta l, and panel 20C33 provides Division B LOCA signal.
In Unit 3 control panels 30C32 and 30C33 provides LOCA signals respectively.
A dry contact of eacn relay (14A-KllA and 14A-KilS) in botn Units are wired in parallel and are connected to the cooling tower load snecding relays (386X3A and 336X3B) so that the relays are energi:ed to drop the cooling tower loads in ene event of a LOCA.
The dry contacts are considered to be isclating devices, wnica will adequately isolate the su, ject load shedding control circuit from the engineerea safeguard system.
This modification does not adveJsely impact the operation of safety related systems.
All control cables required in the rnoc if i ca t ion are non-0, therefore they ar., installed in nt,r;-Q cable trays.
However, in the G.E.
relay cabinet panels, the control cables are wrapped witn thermoflex sleeving from the corresponding dey contact of each relay to the terminal blo ck.
Flex conduits are used from the terminal blocks to the non-saf eguard cabl6 tray to meet separation require-ments in a ccorda n ce with drawing E-1315 and E-1317.
This mocification does not significantly af f ect the combustible leading of the plant and will maintain the capacility of the plant to be safely shutdown in the event of a fire.
This modification does not involve any racwaste system.
Therefore, the guidance provided in IE Circular 80-18 is not applicable.
UFSAR Se ctions 8.0 and 11.6 have been reviewed.
These UFSAR Sections do not specifically address the cooling tower load sheading on LOCA.
- However, UFSAR Section 11.6 will be revised to add a statement that the cooling
{
tower load will De sned in the event of LOCA on either unit.
(
PSAPS Technical Specification Section 3.9, "Auxiliary Electric System" was reviewed.
Tne Technical Specifica-tion does not address ecoling tcwer load snedding therefore, no change is required to the Technical Speci-f i ca t ions.
Page 2 of 5 Rev.,C 1 m RS16 (009) pjg
....,_......_....,......_....r.
Safety Evaluation for i
Modification 2580 PBAPS Tecnnical Specification Appendix B, Sections 3.0 anc 3.1 "Monitoring Requirements" were reviewed.
In ene event of a LOCA at the plant, the cooling towers would be 1
snut down until the LOCA signal is cleared.
Under this I
condition the warm water can be discharged to Conowingo Pond without going through the cooling towers.
l The cooling tower operation is covered ty NPDES permit No. PA 0009733 Rev. 9/1985.
The temperature monitoring requirements to cooling tower operation are covered in PBAPS Technical Spt cif i ca tion Appendix B,
Section 3.1.
As indicated in the NPDES permit (paragraph IC) the l
cooling tower operation is not required during various f
emergencies including a
reactor e me rg e n cy.
Therefore, l
during a LCCA, the cooling tower operation would not be required regardless of plant operating conditions.
Appendix B of tne Tecnnical Specification mandates temper-ature monitoring of Conowingo Fond after seven days of daily calculated flow of less than 15,000 cfs if at that time less than three cooling towers are operating in i
support of one or both units.
j Therefore, one unit in a LOCA condition would require Conowingo Pond the rmal monitoring only after seven days and very possibly not at all.
i IV.
10 CFR 50.59 CHANGES, TESTS AND EXPERIMENTS 1.
An unreviewed safety question is not involved since f
this modi!ication a.
does nor, increase the probability of occurrence i
or the consequences of an accident or malfunction of equipment important to l
safety as praviously evaluated in the Safety Analysis Report.
This modification improves the voltage regulation of the electrical distribution system of tne plant.
Adequate separation between safety 3
related channels is maintained because only I
non-Q cables are added through isolating devices.
(UFSAR Sections 8.0 and 11.6 have t
been reviewed in making this determination. )
l i
I l
f l
Page 3 of 5 i
RS16 (009)
Rev. [1 i
Safety Evaluation for Modification 2580 b.
does not create a possibility for an accident or malfunction of a different type than any previously evaluated in the Safety Analysis Report.
Since this modification improves the voltage regulation, maintains adequate j
channel separation, and does not introduce any new hazards, no accidents or malfunc-tions could o c cu r in the modified system that could not have oc,irred in the present system design.
(UTSAR Sections 8.0 and 11.6 have been reviewed in making enis determination.)
c.
does not reduce the margin of safety as defined in the basis for any Tecnnical Spec-ification.
Technical Specifications f or for the Peach Bottom Atomic Power Station do not address the cooling tower load shedding.
i
'l 2.
There is no change required to PBAPS Technical Specifications.
i V.
10 CFR 50.92 SIG'NIFICANT HA2ARDS DETERMINATION This modification does not require a license amendment, thus a significant hazards determination is not required.
t l
l L
I I
[
f Page 4 of 5 t
Rev. f i ws RS16 (009) spuss 1
7f
Safoty Evaluation for Modification 2580 l
A PPROVA LS :
i BECHTEL:
Prepared by C[h/
Date 8-22-88 Responstole Enginee N ' k /',;, jv Date
?' 2 2
- P I Indeendfnt' Review 4rj
{
I
- ALld44 Cl>$h' l
Date Int ef acing Discipline
(
~
~
j l
- k. h ' M,
Date F/13/#F l
Interfacing 01sfipl:,ne Incepencent Reviewer Licensing Review d---
Date BIl3/EA
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- & Date 8 - 8.T *h Project Ergineer 8 b
/i 3
1, i
PECo:
I Reviewed by @ d [
totd Date E /12 / n r
)
L'ead Divis to p Reviewer e
l L
Date 8f2Akb6 L
Division (Brancn Head or Section HeacJ 0
.'2 Date k2Y
[
Non-ad Divis n Reviewer 2/fVY
=-
=&
Date Non-Leae Division ( Br,anen Head or Se ction He'ad )
,@ b
/
6.,b u
-r,,,1ffMDate 2 d k.'G k'I Nuclear and /Enytyonmental Section Head (If M.E. Division is involved) l I
I Page 5 of 5 Rev. 'd7.m RS16 (009) s plts p~r._,
i O
2880088450 if) CLEAR EtJ31NEERING ENGINEERitG DIVISION N2-1, 2301 Market Street SAFETY EVALUATION FOR MOD 2579 DELAY START OF D-G VENT SUPPLY FNfS PEACH BOTTCM ATOMIC POWER STATION 1.
SUBJECT:
Safety Evaluation to delay the start of the four diesel-generator d
rocm vent supply fans (CA/64, OSV64, OCV64, 00V64) and supole-mental vent supply fans (OAV91, OSv91, OCV91, 00V91) by 40 seconds frcm their present starting secuence.
!!. CotJCLUSION:
This rnodification does; a.
Affect safety-related toulement b.
Not involve an mreviewed safety cuestion c.
Not recuire a technical specification chan;e d.
Maintain the capability to safely shutdom the plant in the event of a fire e.
Not recuire a license arrerdent or prior NRC approval f.
Not involve a significant hazards consideration i1!. DISCUSSION The Peach Bottem voltage regulation study identified the nead to l
delay the start of the four D-G rocm vent supply fans and supplermntal vent supply fans. Currently, each fan is started when its asscciated diesel generator voltage sensin; relay closes I
(approxirutely S seconds after diesel-generator start). During a I
l LOCA with offsite pcwer available, the sta%3n; of these fans l
coincides with the starting of large ECCS rnctors. This ruy l
result in failure of fans to start due to depressed bus voltages.
This rrodification will add a tire delay relay for each pair of 4
l vent supply and supplemntal vent supoly fans to delay their I
starting by 40 seccnds.
This will allcw the bus voltages to I
recover and the f ans to start. A time delay relay will be added l
In each of the diesel-generator voltage regulator panels (OAG13, i
OSG13, OCG13, ODG13).
The new relays are setunically cuallfled for installation in the diesel-generator pan.ls and are cecable e
of ocereting in the envirement present in diesel-generator rocms.
All connections betwaten the new relays and the existing fan control circult.ry will be ra.3de Internal to the voltage regulator panels.
ReV. 1 l
l l
'88008845.i 1
l Delaying the diesel-generator vent supply and supplemental vent j
supply fans will not cause a significant increase in the diesel-generator rocm tenperatures.
In leakage primarily through the outside air damers for the diesel cenerator ventilation fans will provide sufficient corbustion air to allow start and rui of the diesels until the vent fans start and provide ccrrbustion and cooling air. This condition has been strulated during diesel generator testing in the winter when erblent tcmperetures are tcw ercugh initially to prevent outside air decers frert, no:ulating.
The guldance provided in !E circular f 0-18, although censidered, is not applicable sir.ce this is ret a rahaste systcrn.
This trodification does not change the plant as described in the UFSAR.
Sections 8.5 and 10.14 were reviewed in rnaking this deterTninatico.
IV.
10 CFR 50.$9 CH# DES, TESTS #D ENDERIMENTS:
1.
M unreviewed safet" question is not involved because of the folicwing reasons:
A.
The probability of occurrence or the consecuJnces of an accident or r.s1 function of ecv!pNnt leportant to safety prevleusly evaluated in the safety analysis re:crt is not in:reased. This cr.4 fication adds tire delay relays to delay the start of the diesel-generator vent supply and swo1 rental vent supply fans by 40 seconds. The new relays will be trounted in the diesel-1 I
generator voltage regulator panels and are selsmically cuallfled for this location and are capable of operating in the envirement present in the diesel-generator room. Delaying the start of the vent fans for 40 seconds will not adversly affect the tree sture profilos of the diesel-generator rocrns.
- n leakage prirarily through the outside air ca.~oers for the diesel generator ventilation fans will provice sufficient ccrreustion air to allcw start and run of the diesels mtl1 the vent fans are started.
B.
The possibility for an a:ctdent or rm1 function of a different than any evaluated previously in the safety analysis reptr; is not created. This rodlfication adds y
a titre delay relay to celay the start of the diesel-generator rocrn vent fans for 40 seconds. The design of the addittenal circuitry reets all the criteria of the origirst design and the relays are selsmically cuallfled h
for Installation in the diesel-generator panets and are capable of operating in the envircomnt present in the diesel-generator reon.
Celayin; the start of the vent I
fans will rot adversely affect the ternerature profile of the diesel-generator rocms.
In leakage prirarily through the outsidt-air daTeers for the diesel generator Rev. 1 I
I
-3 2 2880088450 ventilation fans will provide sufficient corbustion a:P to allow start and run of the diesels untti the vent fans are started.
C.
The rmrgin of safety as defined in the basis for any technical specificatlon is not reduced. ib technical speelfications address the starting tirnes of the diesel-generator room vent supply fans. Sections 3.9, 4.9 and associated bu,ses have been reviewd in tr.sking this detemiastion.
2.
A change to the technical specifications is rwt recuired since ro technical specifications acdress the starting of the dieselgenerator roan vent fans.
V.
10 CFR 50.92 $!GNIFICAW HC#tOS DETER.M!PaTICtJ:
Tais deterTninstico is not applicable since a IIcense mercent is not recuired.
l t
I l
l I
b i
Rev. 1 l
u.
i 2880088450 f
VI. APPROVALS:
4!M44 Prc. cared by:
[$
Date:
Responsible Engineer
't Date: 9 Nf dd _
f L ~
Branch Head h
h 2-Date: 9 P,\\@
h i
L tbn-Lead Branch Heac i
4
{ O. Vba=~
Date:
/0 f$
r p
Non-Lead branch Head
[
4 Reviewed by:
w Date: &
N ind.gensReviewer hk
[
Date:
TM
'/ /
[
l l NES SecTTU6 H6ad
~
i l
s I
i i
i t
I 1
1 CST / lam /08158801 t
1 j
copy to:
L. 8. Pyrth E. P. McKeown J, 64, Pratt j
R. J. Lees J. F. Franz J. T. Rebb G. A. H,nge r W. M. Alden J. F. O'Rearke l
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W. W. Scwers J. B. McLaugM in R. D. Walker W. J. boyer D. A. Torone DAC (PT,-8) Doctype $65 f
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!!JCLEAR EtGINEERitC DEPARTME'IT EtGINEER!f4 OlV!$1Cf1 N2-1, 2301 Market Street c
Safety Evaluation for Modification 2578 Peach Bettern Atomic Pover Station, Units 2 and 3 j
Doctype 565 Revision 1 SVEJ!OT:
Safety evaluatien fer rnMifying the st.arting logic for the RHR c:rcartment coolers.
b
!!. CCt!CLUS!Ori:
Thit. redificat ten:
affects safety-related eculgment l
a.
b.
does net involve an unreviewed safety cuestien c.
does not recuire a technical speelfication change d.
r-aintains the ability to sa'ely shutdan the clant in l
the event ef a fire 1
cces n:t recuire a license amencmen', er crice fMC r
e.
accroval j
l f.
dces net involve a significant ha: ares detemtnation
!!!. O!SCUSS!CN Modificatic, 257! changes the startin; lo;ic for the Unit 2 a.c t
i Unit 3 RrA c:r osrtrent coolers. The coole s wit t start ce either
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an EHR cwo s' art signal (pre:vit cesign) or when the RPR syster, receives a 1.00A signal (this redlficat ten). With the crese*!
cesign, the RHR ccrTartment coc1 cts ruy not start during a LOCA t
without a less of offsite pxr (l.CC8), in ca.r'.lcular een oniv one offstte pcwer source is available. This is a result, of potential Icw bus volta;e causec by atter cting to start an EMR cwo, the RKR coroartrnant cooler fans, anc cther 460 velt loacs j
at the sa n time.
Starting the cooters at *,he beginning of a LOCA, and celayin; the start cf the RFA pro (cb.'ective of j
redificatten 2564), wr11 eliminate this cessibility.
For i
I ron-acc! cent cceditions, an RMR c:rvartraen; cooler will start f
when its RhR swo starts, l
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The follcwirg RFR cercartrent coolers are affected by this rnodi ficat ion:
A CFA'tdL 2AY:5 Otv25 34V:5 35V05 C CK4tEL 2CV:5
- DV05 3:V5 30V25 B Cw#?dL OEV25 2Fv25
!!.v25 3FV5 0 CFRidL
- GV25 2W?!
3GV5 3HY:5 Start 'c;te # e t*e A and C c'e-e!
D."D. ::rca t-ert cc: lees is ccdffled by :arallellrr a P!GH ;RraILL 'RE!$3! CR ~EACT0; LCi!
LEVEL signal fr n E'~
relav legic circuit "A" v:lth tN existing Ert :WS 41:V C! A !T EEEu:Et CLCSED sig.at te sta ; a co:ter en either a LOCA cr F?R pu o start. The Icgic (Or the S and D chamrel RHR cercartrent ccelers is likewise rrdiflec using RHR relay logic circuit "B".
Safe;uarc channel se aration !S raintaired by ste tir; the 4 a-c C ~snnel cect e t wit"
-R "A" Icgic anc startin; the 5 anc 0 cnar..el c cters w!th Fr; "3" This redification reets the design criteria cf the R"R and se::rcary centalrreat W40 syste-a. A # l re ;ecte:'.10- *e:kl ist and sa#e shute:v, evaluatien Mre ; r:leted te deter-f re that ints recificatien raintains the ca 3:llity te safely shute:>.n the plant in the ever,; cf a (Ire.
Trere are ne ele:t Ical !ca:s a:de: "v this re:l#f estlen.
- hls redlficatico cces rci Involve ra% ste syste-a, trert #cre, the
- ulca.
- e Orcvict: In IE Cir:ular
'.! is rct 4001I:a:ie.
No cs-ces te the ?!a; a*e re:ul'id.
Se: ticar 6.4.4, 4.!, a"d 5.3 were reviewed.
IV.
100FR30.!3 CH#a".ES, TESTS, N.0 EXPEUPEN~S 1.
An unreviewed safety cuest ien ! s r.:t inv h e:',
s.
The DrcbaDIIItY Cf Cccurre*ce er the CCnse WeSces fer ral#u ct ly cf eculer t*,t I PO r '.1"it t e a9 3:* 1 c ea.t c e e
sa#e Y
- eVICusiv evC usted In the 'JSAE Is rct increase:. Tnt s recifl:stice, starts the FE C rfartren* C Clers s:crer tha" the ;revIous ce!I n f
curtn; a LO"A to prevent ecssible startin; prcble-3 cue to ce; aced bus volta;e. Sa#e;uard c*anael se arati n is ralmtained by this redlficatice, b.
This redl#tc: len coes met create a rcssibility c' an d e:ulprent i nc>: t ant t o ral#u ctic c a:C i c ea.t c e a
sa'ety as crevicusiv evaluated in '.he 'JS A:.
The
-cci'icatice i n: h,r e s a L" 4 as am a:d! tic-31 s ', a t i r; c R c erc a r*ye nt c:c ' e r s.
Initiatien sig al #ce r
The creV10us s'. art c rcitica! are ral.itaire".
s 3
This rodification will not reduce the rurgin of safety c.
as defined in the bases of the Technical Specifications.
The RHR system and secondt.s y contalrment HVAC system as described in the Te':hnical Seecificattens are un: hanged.
Sections 3.4.A, 4.4.A, 3.7.C, 4.7.C, and associated bases were reviewed.
2.
A change to the Technical SpectfIcatlons Is not recut red based om a review cf Sections 3.k.4, L.L. A, 3.7.C, 4.7.C.
The RHR and sweencary ccntalrrent H.'A0 syste.s are vn:hangen.
V.
10CFR50.92 $!GNIFICANT HAZARCS DETERMINATICN:
This section is not applicable because an anunment to the license is rot reculred.
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VI.
APPROVALS h
Cate_S*/%'Y$
y Prcosred 0; Rs'sDcosl61e Engineor /'
/4pproved by Oate bli$ l Sb i
Lead Grcuospranch Head Oate i 7 'v J.
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- w ten-leac Eran:n reac Reviewed by Od
/4 Date.' d # /.N P Ince0e N est' Reviewer W f,% ? / / ' - ) %,
Cate /./'-
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- No: lear' & 'Envlrevental Sectlen Head JcM/!an/0515!!01 c oy to DAC (rG-!)
EESE-1 J. J. M Cawley,f' -1 H. Reitm ver, F*JP5
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CIRTIFICATE OF SIRVICE I hereby certify that copies of the foregoing Application were served on the following by deposit in the United States Mail, first class postage prepaid, on the 7th
..vf of September,1988 William T. Russell, Regional Mainistrator U.S. Nuclear Regulatory Cornission 475 Aller,3 ale Road King of Prussia, PA 19406 T. P. Johnson, Resident Inspector U.S. Nuclear Regulatory Commission Peach Botton Atomic Power Station P. O. Box 399 Delta, PA 17314 Mr. Ih mas Gerusky, Direct.or Bureau of Radiological Prot?ction Department of Envircreental Resources P. O. Box 2063 Harrisburg, PA 17120 sz,
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7h h wp 1:uger/ J.' Bradley Attorney for Philadelphia Electric t w pany
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