ML20083R007

From kanterella
Jump to navigation Jump to search
Proposed Tech Specs,Consisting of Change Request 95-02, Revising TS Table 3.3.3-3, ECCS Response Times to Reflect Value of 60 Seconds for HPCI Sys Response Time Instead of 30 Seconds as Specified
ML20083R007
Person / Time
Site: Limerick  Constellation icon.png
Issue date: 05/19/1995
From:
PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:
Shared Package
ML20083R005 List:
References
NUDOCS 9505260291
Download: ML20083R007 (7)
v • d • e


Text

. - . , _ . . . - . _. _ . - .

" i e-. '.

}

i

)

9 ATTACHMENT 1 UMERICK GENERATING STATION UNITS 1 AND 2 DOCKET NOS. 50452 50-353 UCENSE NOS. NPF-39 NPF-85 TECHNICAL SPECIFICATIONS CHANGE REQUEST NO, 95424

SYSTEM RESPONSE TIME" ,

Supporting information for Changes - 3 Pages 9505260291 950519 PDR ADOCK 05000352 P PDR

Docket Nos. 50-352 50-353 Uconse Nos. NPF-39 NPF-85 PECO Energy Company, under Facility Operating License Nos. NPF-39 and NPF-85 for Umerick Generating Station (LGS), Units 1 and 2, respectively, requests that the Technical Specifications (TS) contained in Appendix A to the Operating License be amended as proposed herein, to reflect an increase in the High Pressure Coolant Injection (HPCI) system response time from 30 seconds to 60 seconds, thereby revising TS Table 3.3.3-3. The proposed change to the TS is indicated by the vertical bar in the margin of the TS page 3/4 3-39. The TS pages showing the proposed change are contained in Attachment 2.

We request that, if approved, the TS change proposed herein be issued by April 1,1996, and become effective within 30 days of issuance of the amendment.

This TS Change Request provides a discussion and description of the proposed TS change, a safety assessment of the proposed TS change, information supporting a finding of No Significant Hazards Consideration and Information supporting an Environmental Assessment.

Discussion and Descriotion of the Procosed Chanas The proposed Technical Specifications (TS) Change Request involves increasing the High Pressure Coolant injection (HPCI) system response time from 30 seconds to 60 seconds, revising TS Table 3.3.3-3 accordingly. This change will help prevent unnecessary retesting of the HPCI system.

The HPCI system response time is defined as the time from receipt of a low reactor water level (Level 2) or primary containment high pressure signal, to when the HPCI system reaches design rated flow. The current Emergency Core Cooling System (ECCS) Loss-of-Coolant Accident (LOCA) analysis was performed for Limerick Generating Station (LGS), Units 1 and 2 at a thermal power level of 3622 MWt, which bounds the maximum authorized rated thermal power level of 3458 MWt. The current ECCS-LOCA analysis for LGS assumes a HPCI system response time of 60 seconds, instead of 30 seconds.

The results of this analysis confirm that the HPCI response time of 60 seconds does not affect the licensing basis Peak Cladding Temperature (PCT), which is below 2200*F.

Therefore, we propose that TS Table 3.3.3-3 be revised to reflect the HPCI system response time of 60 l seconds instead of 30 seconds.

$detv Assessment The proposed TS change will increase the High Pressure Coolant Injection (HPCI) system response time from 30 seconds to 60 seconds. This TS change is in accordance with the assumptions provided in the l current Emergency Core Cooling System (ECCS) Loss-of Coolant Accident (LOCA) analysis for Limerick Generating Station (LGS), Units 1 and 2, which considers a HPCI system response time of 60 seconds.

The results of this analysis confirm that the ECCS acceptance criterla of 10CFR50.46 are met. The HPCI system response time of 60 seconds does not affect the licensing basis PCT, which is below 2200*F.

No safety limits are affected by the proposed TS change.

The Loss of Feedwater Flow (LOFW) event has been evaluated for the potential effect of the increase in l the HPCI system response time. The LOFW analysis shows that the HPCI system alone can adequately l maintain the reactor vessel water level above the top of the active fuel. The HPCI system is one of the systems which provides reactor vessel water makeup inventory and is initiated automatically on a low Docket Nos. 50-352 50-353 License Nos. NPF-39 NPF-85 reactor water level (Level 2) signal. An analysis of the LOFW event with the HPCI system alone

_ (assuming a RCIC failure), and a 60 second HPCI system response time, shows that Level 1 is not reached and that the top of the active fuel wHl remain covered throughout the event.

The Direct Current (DC) loads on the safeguard battery were reviewed for the affects of the increased HPCI system response time and no adverse impacts were identified.

The inadvertent HPCI pump start event has also been evaluated for the potential effect of the increased ,

HPCI system response time of 60 seconds. This event causes a core reactivity increase due to the j HPCl flow injection of cold water. The safety analysis assumes that the event begins when the HPCI '

system injects flow into the reactor pressure vessel. Therefore, the HPCI startup time increase from 30 seconds to 60 seconds does not change the calculated results of this event.

Information Suooortina a Findina of No Slanificant Hmrds Consideration We have concluded that the proposed change to the Limerick Generation Station (LGS), Units 1 and 2 j Technical Specifications (TS), which will revise TS Table 3.3.3-3, " Emergency Core Cooling System Response Times' to reflect the High Pressure Coolant Injection (HPCI) system response time of 60 seconds, does not involve a Significant Hazards Consideration. In support of this determination, an '

evaluation of each of the three (3) standards set forth in 10 CFR 50.92 is provided below.

1. The orocosed Technical Soecifications (TS) chanae does not involve a sianificant increase in the orobabuity or consecuences of an accident oreviousiv evaluated.

The proposed TS change will increase the High Pressure Coolant injection (HPCI) system response time from 30 seconds to 60 seconds. The proposed TS change does not involve any physical change in the plant configuration which may cause an accident, or affect safety-related J equipment performance or cause its failure. There is no increase in the consequences of an  !

accident, because the HPCI response time Increase does not affect the licensing basis Peak l Cladding Temperature (PCT), which remains below the regulatory limit of 2200*F.

The Loss of Feedwater Flow (LOFW) event was evaluated for being potentially affected by the l Increased HPCI system response time. The HPCI system is one of the systems which provides reactor vessel water makeup inventory, and is initiated automatically on a low reactor water level (Level 2) signal. The LOFW analysis shows that Level 1 is not reached and that the top of the active fuel will remain covered throughout the event. Therefore, adequate core cooling will be maintained and no fuel damage will result. The probability of fuel failure will not be increased by this proposed TS change.

Therefore, the proposed TS change does not involve an increase in the probability or consequences of an accident previously evaluated.

2. The orooosed TS chance does not create the oossibility of a new or different kind of.f accident from any accident oreviousiv evaluated.

The proposed TS change will increase the High Pressure Coolant injection (HPCI) system response time from 30 seconds to 60 seconds. This proposed change is bounded by the 2-1

~

Docket Nos. 50-352 50-353 Ucense Nos. NPF-39 NPF-85 current Emergency Core Cooling System (ECCS)-Loss-of-Coolant Accident (LOCA) analysis for Umorick Generating Station (LGS) Units 1 and 2. The change in HPCI system response time does not involve any physical modifications to the plant systems or equipment, nor does it introduce a new opera'ional/falure mode, which might cause a different type of accident. In .

case of a Loss of Feedwater Flow (LOFW) event, the HPCI system will operate as designed, maintaining adequate core cooling.

Therefore, the proposed TS change does not create the possibility of 'a new or different kind of accident, from any accident previously evaluated. ,

3. The oronosed TS chanae does not involve a sionificant reduction in a marain of safety.

The following TS Bases were reviewed for potential reduction in the margin of safety:

3/4.5 Emergency Core Cooling System 2.1.4 Reactor Vessel Water Level The TS Bases do not discuss the High Pressure Coolant injection (HPCI) system start time. The margin of safety, as defined in the TS Bases, will remain the same. The proposed TS change is in accordance with the current licensing basis Emergency Core Cooling System (ECCS) - Loss-of Coolant Accident (LOCA) analysis for LGS Units 1 and 2, and does not impact any safety limits of the plant. The K'Cl system will operate as designed during the LOFW event, ,

maintaining adequate core cooling.

Therefore, the proposed TS change does not involve a reduction In a margin of safety.

Information Suncortina an Environmental Assessment An environmental assessment is not required for the change proposed by this TS Change Request because the requested change to the Umerick Generating Station (LGS), Units 1 and 2, TS conforms to the criteria for " actions eligible for categorical exclusion" as specified in 10 CFR.51.22(c)(9). The requested change will have no impact on the environment. The proposed change does not Involve a significant hazards consideration as discussed In the preceding section. The proposed change does not involve a significant change in the types or significant increase in the amounts of any effluents that may be released offsite. In addition, the proposed change does not involve a significant increase in individual or cumulative occupational radiation exposure.

ConciullSD The Plant Operations Review Committee and the Nuclear Review Board have reviewed this proposed change to the Umerick Generating Station (LGS), Units 1 and 2, TS and have concluded that it does not Involve an unreviewed safety question, and will not endanger the health and safety of the public.

3-

l e

e:

I ATTACHMENT 2 UMERICK GENERATING STATION UNITS 1 AND 2 DOCKET NOS. 50-352 50-353 UCENSE NOS. NPF49 NPF-85 ,

l TECHNICAL SPECIFICATIONS CHANGE REQUEST 4

NO. 95424 UST OF AFFECTED PAGES UNIT 1 UNIT 2 3/4 3-39 3/4 3-39 4

6 r , - . _, , __

TABLE 3.3.3-3

-EMERGENCY CORE COOLING SYSTEM RESPONSE TIMES ECCS -RESPONSE TIME (Seconds)

1. CORE SPRAY SYSTEM s 27
2. LOW PRESSURE COOLANT INJECTION MODE OF RHR SYSTEM s 40
3. AUTOMATIC DEPRESSURIZATION SYSTEM N.A.
4. HIGH PRESSURE COOLANT INJECTION SYSTEM s 60 ,
5. LOSS OF POWER N.A.

l

)

i l

LIMERICK - UNIT 1 3/4 3-39

. , . . :e '

1 r

TABLE 3.3.3-3 i

~

EMERGENCY CORE COOLING SYSTEM' RESPONSE TIMES ELSE RESPONSE TIME (Seconds)

1. CORE SPRAY SYSTEM s 27'
2. LOW PRESSURE COOLANT INJECTION MODE OF RHR SYSTEM $ 40 -
3. AUTOMATIC DEPRESSURIZATION SYSTEM N.A.
4. HIGH PRESSURE COOLANT. INJECTION SYSTEM 's 60 l S. LOSS OF POWER N.A.

c

.i 4

f I

l 1-l

' LIMERICK - UNIT 2 3/4 3-39

---..ena -na, . - , - r . - , - - . - - . , - - ,c -

- , , - ,- -

Retrieved from "https://kanterella.com/w/index.php?title=ML20083R007&oldid=2744897"