ML20198H744
ML20198H744 | |
Person / Time | |
---|---|
Site: | San Onofre |
Issue date: | 01/09/1998 |
From: | Nunn D SOUTHERN CALIFORNIA EDISON CO. |
To: | |
Shared Package | |
ML20198H713 | List: |
References | |
NUDOCS 9801130386 | |
Download: ML20198H744 (17) | |
Text
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UN11[0 STATES Of AMERICA NUCl. EAR __REGUL ATORY COMMISSION A:> plication of SDUTHERN CAllf0RNIA
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Docket No. 50 361
[01 SON COMPANY, G R. for a C1 ass 103 License to Acquire, Possess, and Use a Utilization facility as Part of i
Aundment Application Unit No. 2 of the San Onofre Nuclear J)
No. 150, Supplement 1 Generating Station SOUTHERN Calif 0RNIA EDISON COMPANY, H R. pursuant to 10 CFR 50.90, hereby submit Amendment Application No. 150, Supplement 1.
This amendment application consists of Proposed Change Number (PCN) ;53, Supplement 1, to f acility Operating License No. NPF 10.
PCN 453, Supplement 1, is a request to revisc Unit 2 Technical Specification (TS) 3.8.1, "AC Sources Operating," to 1) extend the Offsite Circuit Completion Time from "72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> mfd 6 days from discovery of failure to meet LC0" to "72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> mfd 17 days from discovery of failure to meet LC0" and 2) extend the Emergency Diesel Generator (EDG) Completion Time from "72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> NiQ 6 days from discovery of failure to meet LC0" to "14 days NfD 17 days from discovery of failure to meet LCO " Supplement 1 also adds a new TS 5.5.2.14,
" Configuration Risk Management Program." The purpose of the Configuration Risk Management Program (CRMP) is to ensure that a proceduralized Probabilistic Risk Assessment informed process is in place that assesses the overall impact of plant maintenance on plant risk.
Implementation of the CRMe gg,1 will enable appropriate actions to be taken or decisions to be made to minimize and control risk when performing on-line maintenance for Systems, Structures, and Components with a risk-informed Completion Time.
TS 5.5.2.14 will be applicable to TS 3.8.1 because the Completion Times for TS 3.8.1 are
" risk informed Completion Times."
9001130386 900109 DR ADOCK OS 31
t Subscribed on this i
day of b
1998.
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Respectfully submitted, t
SOUTHERN cal.lf0RNIA EDISCN COMPANY h
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By:
i ight NunA VicePresidbpt i
State of cal'tfernia 0
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fore me, Lfi h D 1 NW personal fy ' appeared Ol(110" Y ). dJ 11Jud personally known to r
me to be the person whose naine is subscrfbed to'the within instrument and acknowledged to me that he executed the same in his authorized capacity, r
and that by his signature on the instrument the person, or the entity upon behalf,of which the person acted, executed the instrument.
.m WITNESS Aand and of ficjal seal.
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UNITED STATES Of AMERICA NUCLEAR REGULATORY COMMISS10h A) plication of SOUTHERN Calif 0RNIA Docket No. 50 362 E0lSON COMPANY, U R. for a Class 103 License to Acquire Possess, and Use aUtilizationfacilityasPartof Amendment Application Unit No. 3 of the San Onofre Nuclear No. 134, Supplement 1 Generating Station
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SOUTHERN Calif 0RNIA EDISON COMPANY, H R. pursuant to 10 CFR 50.90, hereby submit Amendment App 4 cation No. 134, Supplement 1.
This amendment application consists of Proposed Change Number (PCN) 453, Supplement 1, to facility Operating License No. NPf-15.
PCN-453, Supplement 1, is a request to revise Unit 3 Technical Specification (TS) 3.8.1, "AC Sources Operating," to 1) extend the Offsite Circuit Completion Time from "72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> E 6 days from discovery of failure to meet LC0" to "72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> E 17 days from discovery of failure to meet LC0" and 2) extend the Emergency Diesel Generator (EDG) Completion Time from "72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> E 6 days from discovery of failure to meet LC0" to "14 days E 17 days from discovery of failure to meet LCO."
Supplement I also adds a new TS 5.5.2.14
" Configuration Risk Management Program." The purpose of the Configuration Risk Management Program (CRMP) is to ensure that a proceduralized Probabilistic Risk Assessment-informed process is in place that anosses the overall impact of plant maintanance on plant risk.
Implementation of the CRMP bg.1 will enable appropriate actions to be taken or decisions to be made to minimize and control risk when performing on-line maintenance for Systems, Structures, and Components with a risk informed Completion Time.
TS 5.5.2.14 will be applicable to TS 3.8.1 because the Completion Times for TS 3.8.1 are
" risk-informed Completion Times."
. t t
Subscribed on this I
day of 11 R AfW
, 1998.
J Respectfully submitted, i
SOUTHERNCAtif0RNIAEDISONC@PANY f
By:
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Vice President t
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$ tate of California f
[1 County of San Diego A A J^/d,414 h kl1/W On l 4 9Y b
personilliippearedlD'eforeme,i d 1C h i " Q tJ ttei t 3, personally known to f
i me to be'the person U dse nIme is subscribed to'the within instrument and h
acki.owledged to me that he executed the.same in his authorized capacity.
and that by his signature on the instrument the person, or the entity upon behalf of which the person acted, executed the instrument.
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ENCLOSURE (PCN453), Supplement 1 I
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DESCRIPTION AND SAFETY ANALYS15 0F PROP 0$EO CHANGE NPF-10/15 453, SUPPLENENT 1 j
This is a request to revise the San Onofre Units 2 and S lechnical Specification (TS) 3.8.1, "AC Sources - Operating," and add a new TS 5.5.2.14, l
- Configuration Risk Management Program," to be applicable to TS 3.8.1.
i Existina Specifications Unit 2:
See Attachment "A" Unit 3:
See Attachment "B" f
Proposed Specifications i
Unit 21.
See Attachment "C" Unit 3:
See Attachment "D" f
DESCRIPTION Of PROPOSED CHANGES in TS 3.8.1, "AC Sources - Operating:"
l 0
Extend the Second Completion Time in Required Action A.2 for an i
inoperable Offsite Circuit from "6 days from discovery of failure to meet LCO* 60 "17 days from discovery of failure to meet LCO."
Extend the Completion Time in' Required Action B.4 fer a single o
inoperable Emergency Diesel Generator (EDG) from "72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> MD 6 days from discovery of failure to meet LC0" to "14 days AJD 17 days from j
discovery of failure to meet LCO."
l In TS 5.5.2, " Programs and Manuals," add the following:
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5.5.2.14 Configuration Risk Management Program The Configuration Risk Management Program (CRMP) provides a proceduralized risk informed assessment to manage the risk associated with equipment inoperability.
The program applies to technical-s)ecification structures, systems, or components for l
which a ris(-informed Completion Time has been granted.
The program shall include the following elements:
a.
Provisions for the control and implementation of a Level 1 at power internal events PRA informed methodology.
The assessment shall be capable of evaluating the applicable plant configuretion.
b.
Provisions tor performir; an assessment prior to entering the LC0 Condition for treplanned activities, c.
Provisions for performing an assessment after entering the LC0 Condition for unplanned entry into the LC0 Condition.
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Provisions for assessing the need for additional actions after the discovery of additional equipment out of service conditions while in the LC0 Condition, e.
Provisions for considerin other applicable risk significant If'l contributors such as leve 2 issues, and external events, qualitatively or quantitatively."
Included in Attachment "C" for Unit 2 and Attachment "D" for Unit 3, respectively, are revised LC0 pages 3.8 1 and 3.8 2, revised Bases pages B3.8 6, B3.8 9, and B3.8-29, and revised Administrative Section 5.5.2.
Due to text overflow, Bases pages B3.8 10 through B3.8 21 are included for 5 "(b 1 completeness.
BACKGROV!iQ San Onofre Units 2 and 3 are each equipped with two seismically qualified, Class lE, diesel engine driven generators which supply backup electrical power to the 4160 volt vital AC busses.
Each EDG is connected to the 4160 volt bus of a load group.
Each EDG is designed to automatically start in the event of a bus undervoltage condition on the 4160 volt Class lE bus to which it is connected (loss of voltage signal LOVS) or upon receipt of a Safety injection Actuation Signal (SIAS).
Each EDG is designed to start automatically so that within 10 seconds following receipt of a start signal it is operating at rated speed and ready to begin load sequencing.
The EDG is sized to supply reliable power to all safety related loads in its respective load group, as well as specific nonsafety related loads.
Loads supplied by each EDG are determined on the basis of nameplate or service factor rating, pump pressure and flow conditions, or pump runout conditions.
Each EDG has as continuous load rating of 4700 KW, for emergency standby duty, the manufacturer allows specific overload values up to 116.1% of continuous duty rating based on the total hours the EDG is operated per year.
The EDGs may be controlled or placed within their specific operating modes from the mimic bus panel in the control room or fro a local panel within each EDG room. These provisions allow EDG operation for surveillance testing and manual start and load operations, as well as local operations.
The EDGs are described in Section 8.3.1 of the San Onofre Units 2 and 3 Up6ated final Safety Analysis Report (UFSAR).
MSCUSSION Of CHANGE The San Onofre Units 2 and 3 Technical Specification (TS) 3.8.1 requires if an EDG is declared inoperable for any reason, the EDG must be restored to operable status within "72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> mfd 6 days from discovery of failure to meet LC0" or place the plant in Hot Standby within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and Cold Shutdown within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. The proposed amendment would allow up to "14 days mfd 17 days from l N p' f I
discovery of failure to meet LC0" to restore EDG operability.
The proposed 2
3
_ _ _ _.._.__ _ _ _ _ _ _ _ _. _ _ _ _ _. y 1
t amendment also extends the.Second Completion Time for an. inoperable Offsite -
Circuit:from "6 days from discovery =of' failure to meet LC0" to "17 days from l
I discovery of failure to meet LC0" to be consistent with the change in the EDG l
Completion Time, j
The Second Completion Time for the EDG and Offsite Circuit provides a limit on the maximum time allowed for any combination of required alternating current power sources to be inoperable during any single contiguous occurrence of failing to meet the Limiting Condition for Operation.
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Implementation of this proposed Completion Time extension will.
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Allow increased flexibility in-the scheduling and performance of preventive maintenance, o
Reduce the number of individual entries into LCO conditions-by providing i
sufficient time to perform related maintenance tasks with a single entry.-
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' Allow better control of resource allocation. During outage maintenance windows, plant personnel and resources are spread across a large number and wide variety of maintenance tasks. Allowing on line preventive-1 maintenance (including overhauls) gives the flexibility to focus more i
quality resources on any required or elected CDG maintenance.
o Avert unplanned plant-shutdowns and minimize the potential for requests for Notice of Enforcement Discretions Risks incurred by unexpected plant shutdowns can be compa(N0EDs).
rable to and often exceed those j
associated with continued power operation.
o improve EDG availability during shutdown modes.
o permit scheduling of EDG overhauls of up to 14 days on-line.
CE NPSU 996 CE0G " Joint Applications Report for Emergency Diesel Generators Completion Time Extension, provided detailed results of an integrated assessment of the overall risk associated with the adoption of the proposed EDG Completion Time extension.
This evaluation includes an assessment considering the risk associated with "at power," " transition," and " shutdown" operations and utilized Probabilistic Safety Analysis (PSA) methodology to fully evaluate the effect of the EDG Completion Time extension. Southern California Edison below to include an(SCE) has augmented the CE NPSD 996 analysis as described assessment of the impact of extending the EDG Com)1etion Time to 14 days.
The augmented study uses San Onofre specific data witch reflects'the high reliability of the San Onofre AC power system.
This high L (( 1 i reliability is due in part to the recently installed Inter Unit 4.16 kV Bus Cross-Tie. Approval for use of the Cross Tie is still pending.
Assessment of At power Risi The evaluation of "at power ruk": change resulting from the extended Completion Time was perfoisY using ob.t specific information from each of
.the. participating CEOG membecs.
T1f 6 mented results for San Onofre Units 2 5il and 3 3rovided in Tables 1-1,1-2, ar/l 3 show that the proposed Completion Time;cianges could increase the aveidtp core damage frequency (CDF) by 0.4%.
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Table 1-1 CORRECTIVE MAIN 1ENANCE DIESEL GENERATOR COMPLETION TIME CONDITIONAL RISK CONTRIBUTION i
PARAMETER Core Damage frequency EDG Success Criteria 1 of 4 PresentCompletionTime, days 3
Proposed C';mpletion Time, days 14 A1. Conditionti Risk, per year (1 EDG unavailable) 5.85E-05 A2.por,dttionalRisk,peryear(1EDGneveroutfor 2.67E 05 T/M)
A3. Increase in Risk. per year 3.18E-05 A4. Single Completion Time Risk Current 2.61E-07 AS. Single Completion Time Risk. Proposed 14 day 1.22E-06
,y A6.. Downtime frequency, per year per diesel 0.63 A7. Yearly Completion Time Risk. Current, per 1.65E 07 yr/ diesel AB. Yearly Completion Time Risk Propose., per 7.68E 07 yr/ diesel A9. Actual Duration, hrs / event 23.8 A10. Single Completion Time Risk (based on actual 8.64E-08 data)
All. Yearly Completion Time Risk /yr/ diesel (based on 5.44E-08 actual data)
' Utilizing EDG cross tie under 10CfR50.54X for non LOCA events.
'Testinn and Maintenance 4
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Table 1-2 i
PREVENTIVE MAINiiNANCE DIESEL GENERATOR COMPLETION TIME CONDlil0NAL RISK CONTRIBUTION j
i PARAMETER Core Damage Frequency l
3
[DG' Success Criteria 1-of 4 Present Completion Time, days 3
Proposed Completion Time, days 14 Bl. Conditional Risk, per year (1 EDG unavailable) 2.83E 05 B2. [onditional Risk, per year (1 EDG never out for 2.67E-05 T/M)
B3, increase in Risk, per year 1.60E 06 B4. Single Completion Time Risk, Current 1.32E 08 B5. Single Completion Time Risk, Proposed 14 day 6.14E 08 g
,3 B6. Downtime frequency, per year per diesel 1.0
- 87. Yearly Completion Time Risk, Current, per 1.32E-08 yr/ diesel B8.. Yearly Completion Time Risk, Proposed, per 6.14E-08 yr/ diesel B9. Proposed Downtime (avg hrs / train /yr) 224 B10. Proposed Duration, hrs / event 224 Bil. Single Completion Time Risk (based on proposed 6.14E-08 14 day Completion Time)
B12. Yearly Completion Time Risk /yr/ diesel (based on 4.09E-08 average annual proposed downtime)
Utilizing EDG cross-tie under 10CFR50.54X for non LOCA events.
Testing and Maintenance 5
-j Table 13 AVERAGE-RISK RESULTS DlESEL GENERATOR COMPLETION TIME CONDITIONAL RISK CONTRIBUTION i
PARAMETER Core Damage i
frequency l
8 EDG Success Criteria 1 of 4 Present Completion Time, days 3
Proposed Completion Time, days 14 Cl. Proposed Downtime hrs /yr/ diesel' 239 gg,1 C2. Average Risk (current), per yr 2.67E 05 C3 Average Risk (proposed), per yr 2.68E 05 l
f C4. Change factor from baseline Risk
<l.004
Utilizing EDG cross-tie under 10CfR50.54X for non LOCA events..
CE NPSD 996 incorrectly indicated the proposed downtime as 220 hr/yr/ diesel.
j Assessment of Transition Risk Transition risk represents the risk associated with reducing power and going to hot shutdown or cold shutdown modes. This risk identifies the tradeoff l
between shutting the plant down and restoring EDG operability whila the plant continues to operate. The results of this risk assessment indicate that lb t 1 e
performing a 14-day Completion Time corrective maintenance at power, as i
compared to shutting down the' plant to perfonn the work, would be risk i
beneficial.
i Assessment of Shutdown Risk Shutdown risk is associated with removing an EDG from service while the plant i
'is in a shutdown mode of operation. The results of this risk assessment
-indicate that performing corrective or preventive maintenance at power would:
1)_
be risk neutral when compared with early outage maintenance, and 2) result in a slight increase in risk when compared-with late outage maintenance.
-However, performing EDG maintenance at power will provide greater EDG
- reliability upon entering shutdown modes than if maintenance had been i'
performed at the end of a refueling outage, increasing the EDG Completion gIf
- 7 Time to 14 days would not change this conclusion.
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The CE NPSD 996 report evalaaled the impact of the proposed Completion Time extension on large early release scenarios.
Large early release scenarios are releases arising from 1) Containment Bypass events (e.g., interfacing system LOCAs, steau generator tube ruptures with concomitant loss of steam generator isolation), 2) Severe Accidents accompanied by loss of containment isolation, and 3) Containment failure associated with Energetic events in Containment.
The evaluation concluded that the increased unavailability of one EDG an Completion Time of 7 days and a once per refueling-cycle Completion Time of 10 days-will result in a negligible impact on large early release probability.
These conclusions remain valid when using the data in the Tables above in support of a Completion Time of 14 days.
Therefore, increasing the Completion fg.1,
Time from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> o 14 days would not change the conclusions of CE NPSD 996.
The CE NPSD 996 report concludes that an EDG Completion Time extension form 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 7 days with a once per refueling cycle 10 day Completion Time may potentially result in a small increase in the "at power" risk.
However, when the full scope of plant risk is considered, the risks incurred by extending the Completion Time for either corrective or preventive maintenance will be substantially offset by plant benefits associated with avoiding unnecessary plant transitions, reducing risks during plant shutdown operations, and improved EDG reliability upon entering shutdown.
The data and risk results pertaining to the San Onofre units were sup)11ed and endorsed by Southern California Edison.
Taken in concert with t1e data and risk results based on a proposed 14-day EDG Completion Time (presented in Tables 1-1, 1-2, and 1 3, above) the data and risk results in CE NPSD 996 are still valid and support the requested 14 day EDG Completion Time.
The proposed amendment also adds a new TS 5.5.2.14, " Configuration Risk Management Program" The purpose of the Configuration Risk Management Program (CRMP) is to ensure that a proceduralized Probabilistic Risk Assessment-informed process is in place that assesses the overall impact of plant maintenance on plant risk.
Implementation of the CRMP will enable appropriate actions to be taken or decisions to be made to minimize and control risk when performing on-line maintenance for Systems, Structures and Components with a risk-informed Completion Time.
TS 5.5.2.14 will be applicable to TS 3.8.1 gK1 because the Completion Times for TS 3.8.1 are " risk-informed Completion Times."
To ensure plant safety is maintained and monitored San Onofra will implement a Configuration Risk Management Program (CRMP).
1.
Purpose of CRMP The purpose of the Configuration Risk Management Program (CRMP) is to ensure that a proceduralized Probabilistic Risk Assessment (PRA)-
informed process is in place that assesses the overall impact of plant maintenance on plant risk.
Implementation of the CRMP will enable appropriate actions to be taken or decisions to be made to minimize and control risk when performing on-line maintenance for Systems, Structures and Components (SSCs) with a risk-informed Completion Time.
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. 2.
Sc:pe of CRN?
The scope of the SSCs included in the CRMP are those SSCs considered l
High Safety Significant per the Maintenance Rule regulatory guide (Regulatory Guide-1.160, Rev. 2),
i The Configuration Risk Management Program (CRMP) includes the following components and key elements:
- Components I
a.
Risk Assessment 1 91 b.
Tier 2 restriction.
c.-
Level 2 and External Events i
d.
Decision Making Process e.
Associated Procedures i
Key Element 1.
Implementation of CRMP j
The intent of the CRMP is to implement a(3) of the Maintenance Rule (10CFR50.65) with respect to on line maintenance for risk informed technical specifications, with the following additions /
clarifications:
a.
The scope of SSCs to be included in the CRMP will be the SSCs considered High Safety Significant per Regulatory Guide 1.160, b(( 1 Rev. 2.
- b.
The CRMP assessment tool is PRA informed, and may oe in the form of either a risk matrix..an on line assessment, or a direct PRA assessment, c.
CRMP will be invoked as follows for:
Risk-Informed Inoperability: A risk assessment will be performed prior to entering the LC0 Condition for preplanned activities, for unplanned entry into the LC0 Condition, a i
risk assessment will be performed in a timeframe consistent with the plant's Corrective Action Program.
Add';tional SSC Inoperability and/or loss of Functionality:
When in the risk informed Completion Time, if an additional high safety significant SSC becomes inoperable /non functional, a risk assessmerit shall be performed in a timeframe consistent with the plant's Corrective Action Program.
d.
' Tier 2 commitments apply for planned maintenance only, but will be evaluated as part of the Tier 3 assessment for unplanned occurrences.
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Control & Use of the CRNP Assessment Tool a.
Plant modifications and procedure changes will be monitored, assessed, and dispositioned.
Evaluation of changes in plant configuration or PRA model features can be dispositioned by implementing PRA model changes or by the qualitative assessment of the inipact of the changes on the CRMP assessment tool.
This qualitativa asse:,sment recognizes that changes to the PRA takn time to i
implement and that changes can be effectively compensated for without compromising the ability to make sound engineeringjudgments.
Limitations of the CRMP assessment tool are identified and understood for each specific Completion Time extenstor,.
b.
Procedures exist for the control and application of CRMP assessment tools, including description of process when outside the scope of the CRMP assessment tool.
stb Key Element 3.
Level 1 Risk-Informed Assessment The CRMP assessment tool is based on a level 1, at power, internal events PRA model.
The CRMP assessment may use any combination of quantitative and qualitative' input.
Quantitative assessments can include reference to a risk matrix, pre existing calculations, or new PRA analyses.
f a.-
Quantitative assessments should be performed whenever necessary for sound decision making, b.
When quantitative assessments are not necessary for sound decision making, qualitative assessments will be performed.
Qualitative assessments will consider applicable, existing insights from quantitative assessments previously performed.
Key Element 4.
Level 2 Issues / External Events External events and Level 2 issues are treated qualitatively and/or-quantitatively, Guidance for implementing the CRMP is provided by plant procedures.
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SAFETY-ANALYSIS-LThe proposed; change: described above shall be deemed to' involve a significant
-hazards consideration;if: there is a: positive finding in any one of the following areasr (1. -
Will operation of the-facility in accordance with this proposed change involve a significant increase in the probability or consequences of an
-accident--previously evaluated? -
Response:--No-The Emergency DieselzGenerators (EDGs) are backup-alternating current power sources design to power essential safety systems in the event of a loss of offsite power.
EDGs are not accident initiators in any accident 4
previously evaluated. Therefore, this change does not involve an.
increase in the_ probability of at accident previously evaluated.
The EDGs provide backup power-to components that mitigate the Lconsequences of accidents. The proposed changes to the Completion Times do not affect any of the assumptions used-in the deterministic safety analysis.
To fully evaluate the effect of the EDG Completion Time extension, Probabilistic Safety Analysis (PSA) methods were utilized. The results of these analyses show no significant increase in the core damage frequency. As a.rer. ult, there would be no significant increase in the consequences of accidents previously evaluated, i
The Conf quration Risk Management Program is an Administrative Program that assesses risk based on plant status. Adding the requirement to implement this progran-for Technical Specification 3.8.1-does-not affect
$$1 the probability or the consequences of an accident.
Therefore, this change does Dat. involve a significant increase in the-probability.or consequences of any accident previousiy evaluated.
2; Will operation of the facility in accordance with this proposed change create the possibility of a new or different kind of accident-from any
- accident previously evaluated?
Response: No h.
This proposed change does not alter the design,-configuration, or method
. of operation of the plant. Therefore, this change dagji not_ create thy possibility of a new or different kind of accident from any previously
' evaluated.
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3.
Will operation of the facility in accordance with this proposed change involve a significant reduction-in a margin of safety?-
-Response: ' No-The proposed ~ changes'do not' affect the Limiting Conditions for Operation-or their Bases that are used in the deterministic analyses ~to establish the margin of safety.
PSA evaluations were used to evaluate these changes and these evaluations determined.that the changes are either risk neutral or risk beneficial.
Therefore, this chanqc does agi Involve a significant reduction in the margin of safety.
Safety and'Sianificant Hazards DeterminatiqD Based on the above Safety Analysis,-it is-concluded that: 1) the proposed change.does not' constitute a significant hazards: consideration as defined by-10 CFR 50.92 and 2) there is reasonable assurance that the health and safety of the public will not be endangered by the proposed change. Moreover, because this action does not involve a significant hazards consideration, it.
will also not result in a condition which significantly alters the impact of the station on the environment-as described in the NRC Final Environmental St ater..ent.
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P ATTACHMENT "A" 4
EXISTING SPECIFICATIONS UNIT 2
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