ML110350379

Request for Additional Information Regarding License Amendment Request Proposing Changes to the Number of Required Operable Main Steam Safety Valves

ML110350379
Person / Time
Site:	Three Mile Island
Issue date:	02/14/2011
From:	Peter Bamford Plant Licensing Branch 1
To:	Pacilio M Exelon Nuclear, Exelon Generation Co
Bamford, Peter J., NRR/DORL 415-2833
References
TAC ME4808
Download: ML110350379 (3)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555*0001 February 14, 2011 Mr. Michael J. Pacilio President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555

SUBJECT:

THREE MILE ISLAND NUCLEAR STATION, UNIT 1 - REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST PROPOSING CHANGES TO THE NUMBER OF REQUIRED OPERABLE MAIN STEAM SAFETY VALVES (TAC NO. ME4808)

Dear Mr. Pacilio:

By letter dated September 24, 2010 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML102780570), Exelon Generation Company. LLC (Exelon, the licensee) submitted a license amendment request (LAR) proposing to revise the Technical Specifications (TSs) for Three Mile Island Nuclear Station, Unit 1. The proposed changes would modify Technical Specification 3.4.1.2.3 regarding the number of main steam safety valves required to be operable as a function of power level.

The Nuclear Regulatory Commission staff has been reviewing the response and has determined that additional information is needed to complete its review. The specific question is found in the enclosed request for additional information (RAI). The question was sent via electronic transmission on February 3, 2011, to Ms. Wendi Croft, of your staff. The draft question was sent to ensure that the question was understandable, the regulatory basis for the question was clear, and to determine if the information was previously docketed. The draft question was discussed with Ms. Croft on February 4,2011. It was agreed that a response to this RAI would be submitted by March 21 , 2011.

Please contact me at 301-415-2833, if you have any questions.

Sincerely, .

/J ,J ()

f0~~

Peter Bamford, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-289

Enclosure:

As stated cc: Distribution via Listserv

REQUEST FOR ADDITIONAL INFORMATION THREE MILE ISLAND NUCLEAR STATION, UNIT 1 PROPOSED TECHNICAL SPECIFICATION CHANGES REGARDING NUMBER OF REQUIRED OPERABLE MAIN STEAM SAFETY VALVES DOCKET NO. 50-289 By letter dated September 24, 2010 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML102780570), Exelon Generation Company, LLC (the licensee),

submitted a license amendment request (LAR) for Three Mile Island Nuclear Station, Unit 1 (TMI-1). The licensee proposes to modify TMI-1 Technical Specification 3.4.1.2.3 regarding the number of main steam safety valves allowed to be inoperable as a function of power level. In order for the NRC staff to complete its review of the LAR, a response to the following request for additional information is requested.

1. Attachment 1 to the submittal, document number 86-9054640-02, page 47, assigns a value of 6.9% full power (FP) uncertainty to the overpower trip setpoint, independent of power level. Please provide justification that this uncertainty is applicable to all of the power levels analyzed.

Enclosure

February 14, 2011 Mr. Michael J. Pacilio President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555

SUBJECT:

THREE MILE ISLAND NUCLEAR STATION, UNIT 1 - REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST PROPOSING CHANGES TO THE NUMBER OF REQUIRED OPERABLE MAIN STEAM SAFETY VALVES (TAC NO. ME4808)

Dear Mr. Pacilio:

By letter dated September 24, 2010 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML102780570), Exelon Generation Company, LLC (Exelon, the licensee) submitted a license amendment request (LAR) proposing to revise the Technical Specifications (TSs) for Three Mile Island Nuclear Station, Unit 1. The proposed changes would modify Technical Specification 3.4.1.2.3 regarding the number of main steam safety valves required to be operable as a function of power level.

The Nuclear Regulatory Commission staff has been reviewing the response and has determined that additional information is needed to complete its review. The specific question is found in the enclosed request for additional information (RAI). The question was sent via electronic transmission on February 3, 2011, to Ms. Wendi Croft, of your staff. The draft question was sent to ensure that the question was understandable, the regulatory basis for the question was clear, and to determine if the information was previously docketed. The draft question was discussed with Ms. Croft on February 4,2011. It was agreed that a response to this RAI would be submitted by March 21, 2011.

Please contact me at 301-415-2833, if you have any questions.

Sincerely, Ira!

Peter Bamford, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-289

Enclosure:

As stated cc: Distribution via Listserv DISTRIBUTION:

RidsNrrPMThreeMilelsland Resource PUBLIC LPLI-2 R/F RidsAcrsAcnw_MailCTR Resource RidsNrrLAABaxter Resource RidsOgcRp Resource RidsRgn1 MailCenter Resource RidsNrrDorlDpr Resource RidsNrrDorlLpl1-2 Resouce AGuzzetta, NRR RidsNrrDssSrxb Resource ADAMS Accession Number' ML110350379

• via email OFFICE LPL1*2IPM LPL1*2ILA LPL 1-2/LA LPLI-2/BC NAME PBamford ABaxter* AUlses* HChernoff DATE 214111 217111 1/28111 2/14111 OFFICIAL RECORD COPY