ML090900502

Meeting Summary of Pre-application Meeting with Exelon on License Amendment Request for Automatic Depressurization System for LaSalle

ML090900502
Person / Time
Site:	LaSalle
Issue date:	04/09/2009
From:	Sands S Plant Licensing Branch III
To:
Sands S,NRR/DORL, 415-3154
References
Download: ML090900502 (15)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 April 9, 2009 LICENSEE: Exelon Nuclear FACILITY: LaSalle County Station

SUMMARY

OF DECEMBER 11,2008, PRE-APPLICATION MEETING WITH EXELON NUCLEAR GENERATION COMPANY, REGARDING LICENSE AMENDMENT REQUEST FOR AUTOMATIC DEPRESSURIZATION SYSTEM On December 11, 2008, a Category 1 public meeting was held between the U.S. Nuclear Regulatory Commission (NRC) and representatives of Exelon Nuclear Generation Company (the licensee) at the NRC Headquarters, One White Flint North, 11555 Rockville Pike, Rockville, Maryland. The purpose of the meeting was to discuss a pre-application license amendment request (LAR) for the automatic depressurization system (ADS). A list of attendees is provided as Enclosure 1.

The licensee presented information pertaining to the proposed changes to the ADS (See ). The presentation included: an overview of the ADS, a review of background information regarding the need for a LAR for the ADS, a review of the technical and regulatory aspects of the planned LAR, a review of an outline of the draft LAR with respect to the required scope and level of detail, and a discussion the path necessary for the LAR approval.

The staff discussed with the licensee the ADS function of the safety relief valves and the low low setpoint (LLS) of these valves, both from a current design perspective, and a proposed modification aspect. Also discussed was the importance of maintaining the safety function of the ADS during any postulated condition and the ADS accumulator backup gas system.

The licensee indicated they planned to submit the LAR for the ADS in the near future.

Members of the public were not in attendance. Public Meeting Feedback forms were not received.

Please direct any inquiries to me at 301-415-3154, or SPS1 @nrc.gov.

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s~~hl;:~dS' pro~ect~anager Plant Licensing Branch 111-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-373 and 50-374

Enclosures:

1. List of Attendees

2. Licensee Handout cc w/encl: Distribution via ListServ

LIST OF ATTENDEES December 11, 2008, MEETING WITH EXELON PROPOSED PRE-APPLICATION LICENSE AMENDMENT REQUEST (LAR) MEETING WITH EXELON TO DISCUSS THE AUTOMATIC DEPRESSURIZATION SYSTEM FOR LASALLE COUNTY STATION, UNITS 1 AND 2 Name Organization Phone Number Stephen Sands NRC/NRR/DORLlLPLlII-2 301-415-3154 Russell Gibbs NRC/NRRIDORLlLPLlII-2 301-415-7198 Jon McHale NRCIDCI/CPTB 301-415-3254 Ben Parks NRC/NRRIDSS/SRXB 301-415-6472 Jay Houston Exelon 815-415-2810 Mike Peters Exelon 815-415-2591 Alison Mackellar Exelon 630-657-2823 Terrence Simpkin Exelon 815-415-2800 Steve Tingen NRC/NRRIDCI/CPTB 301-415-1280 Mike Mahoney NRC/NRRIDORLlLPLlII-2 301-415-3867 Richard Lobel NRC/NRRIDSS/SCVB 301-415-2865 Ahsan Sallman NRC/NRRIDSS/SCVB 301-415-2830 ENCLOSURE 1

ENCLOSURE 2 Exel n, Nuclear Meeting Participants - Exelon Terry Simpkin - LaSalle Regulatory Assurance Manager Jay Houston - LaSalle Regulatory Assurance Mike Peters - LaSalle Design Engineering Patrick Simpson - Licensing Manager Alison Mackellar - Licensing Engineer

Exel n.

Nuclear Introduction

'-",,~~.

~ Overview of the Automatic Depressurization System (ADS)

~ Review background information regarding the need for a License Amendment Request (LAR) for the ADS

~ Review the technical and regulatory aspects of the planned LAR

~ Review an outline of the draft LAR with respect to the required scope and level of detail

~ Discuss the path necessary for LAR approval

Exel n.

Nuclear Issue Review

~ Proposed change is needed to correct a degraded non-conforming condition and to resolve a non conservative Technical Specification (TS)

~ Common pneumatic supply utilized to support the Low-Low Setpoint (LLS) function of the Safety Relief Valves (SRVs) and the ADS function of the SRVs

~ The sharing of a common pneumatic supply could result in a condition that prevents the ADS SRVs from performing their design function

Exel n, Nuclear Issue Review

~ The current TS bases for the allowed outage time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> is that the ADS accumulator backup compressed gas system nitrogen bottles are only required to provide long-term cooling and would not be required immediately following an accident

~ However, due to the shared interface between the pneumatic supply utilized by both LLS and ADS, sufficient compressed gas might not be available to ensure both the LLS and ADS SRV functions are met

Exel n, Nuclear Interface between Div 2 ADS and LLS Basic Logic to Energize SRV Solenoids ADS and LLS functions only SRV A Solenoid B Solenoid C Solenoid N2 Bottle Bank C ADS Div 1 ADS Diy 2 South LLS LLS 0 ADS Div 1 ADS Diy 2 North LLS LLS E ADS Diy '1 ADS Diy 2 South LLS LLS F

H K LLS (Unit 2) LLS LLS {Unit 1}

L M

P LLS (Unit 2) LLS LLS (Unit 1}

R ADS Diiy 1 ADS Oiv 2 South S ADS Diy "1 ADS Diy 2 North LLS LLS U ADS Diy 1 ADS Diy 2 South LLS LLS v ADS Diy 1 ADS Oiv 2 North

SIMPLIFIED SCHEMATIC OF THE ADS PNEUMATIC SYSTEM r-------------

I I

--, ADS  :

l Relief-LLS-ADS  :

EOE~genCr Pressurization Station Pressure Regulating Valve Non-SR North Nitrogen Bottle Bank Dryer &

Filters Other Normal Suction I ~ Non-SR is from Drywell Loads --~ ADS  :

Dryer &  : Relief-LLS-ADS 1

Filters Non-SR

-t SR Pressure Regulating Valve r-------------,

--~ ADS  :

Relief-LLS-ADS  :

~J Emergency South Nitrogen Bottle Pressurization Station Bank

SIMPLIFIED SCHEMATIC OF THE ADS/LLS INTERFACE PREVIOUS CONFIGURATION

---

~

I----N~ i I I I I I I Emergency  : Other  :

Pressurization I N-+jADS SRVs i Station I I

I I

I I r.l

---

~~--------------~

I I r-----------------------------------------------------------

r I

I Exhaust I

I I

I I

I I

Solenoid A ADS Div 1 I

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Pressure I I

Regulating Valve I I

I I

I I

I Non-SR I pon-sRT sR I

I I

I

,I From Non-SR iI N-Q ~I SolenoidC .

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I I

Compressor i Non-ADS Relief &LLS SRV Pneumatic :

Actuator :I

l\ccurnulator I

I (lO gal) I I

I I

I Nitrogen Bottle Bank I L JI (Typical 1 of 2) Typical for ADS SRVs C, "D" "E", "S", "U"

SIMPLIFIED SCHEMATIC OF THE ADS/LLS INTERFACE CONFIGURATION WITH MODIFICATIONS COMPLETE Emergency Pressurization I N~

I I

Station

Other

-- N---..: AD S SRVs I

,. ~

rn "'" i Valve removed I

I I

,r----'---'---'-'-'--- ~~--------------

~

./ ------

, ~

\

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,-."...,.~ ~.

~.

-._-_._.--_._-~--~-- ,.i AuxBldg r------------------------------------------------------------

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_._._._._._._._._._.~

I Exhaust :I Components I ,.' RxBldg I I I added I ',' I I

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-_._._-----_._-_._._.~-

---

" I I

I -

I I

I I

I I

I \ Cf4'. \

, Pressure Z

SR

+

• I

\ I Regulating Valve

\"

. I

.i _--_

Solenoid B

,_ _ r Non-SR ADSDiv 2 ron-SR~SR R~li~f &: T.T .S I

I I

I I

Supply from .

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Non-SR IN Compressor SRV Pneumatic  :

Non-ADS Actuator  :

Accumulator I r

I (10 gal) I I I Nitrogen Bottle Bank I I 1 ----------------------------------------------- ~

(Typical 1 of 2) Typical for ADS SRVs "C", "D", "E", "S", "D"

Exel n Nuclear LAR Outline

'-~...................,

~ The current CT for TS 3.5.1 Condition D that allowed 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to restore ADS accumulator backup compressed gas system bottle pressure to > 500 psig is being deleted.

~ Existing TS 3.5.1 Condition H is being revised to include the condition associated with inoperability of the ADS accumulator backup compressed gas system.

~ SR 3.5.1.4 will be modified to maintain a minimum bottle pressure of 500 psig for each bottle bank or a minimum bottle pressure of 1100 psig for the reserve bottle.

Exel n, Nuclear LAR Outline

~ To ensure the safety function of the ADS SRVs is maintained during any postulated condition, the ADS accumulator backup compressed gas system will be required to be operable whenever the ADS function is required to be operable.

~ A proposed new section of the LaSalle Technical Requirements Manual (TRM) and TRM Bases will ensure that the applicable function of the low and medium LLS SRV be operable.

~ Failure of the low and medium range LLS function has the potential to adversely impact ADS operability and therefore the new TRM will require entry into the revised TS 3.5.1 Condition for two or more required ADS valves inoperable should either the low or medium function of the affected SRVs be inoperable.

i

.I J

Meeting Summar v ML090900502 NRC001 OFFICE DORULPL3-2/PM DORULPL3-2/LA DORULPL3-2/BC NAME SSands THarris RGibbs DATE 04/8/09 04/9/09 04/9/09