ML071580118

Response to RAI Alternate Nitrogen System Pressure

ML071580118
Person / Time
Site:	Monticello
Issue date:	06/05/2007
From:	Tam P NRC/NRR/ADRO/DORL/LPLIII-1
To:	Arias J, Loeffler R Nuclear Management Co
References
TAC MD4292
Download: ML071580118 (2)

Text

From: Peter Tam To: Arias, Jesus; Loeffler, Rick Date: 06/05/2007 4:17:03 PM

Subject:

Monticello: Response to RAI re. Alternate Nitrogen System Pressure (TAC MD4292)

Rick, Jay:

Our reviewers had looked at your 5/25/07 letter, transmitting additional information to support the proposed amendment requested by your 1/30/07 application. We were looking for you to summarize the calculation, including the assumptions and results, which would justify why 410 psig is the correct number. The submittal should make it clear that 410 psig is a conservative value, in that a supply pressure of 410 psig ensures that the Alternate Nitrogen System can perform its safety function of actuating the SRVs (for the ADS function) during a LOCA by depressurizing the reactor vessel to permit low pressure ECCS injection, and that a supply pressure of 410 psig is adequate for more SRV actuations than is required under worst-case situations.

If you would like us to clarify this information in a conference call, we would be glad to do that.

Otherwise, please provide the requested information within 30 days of this e-mail, or by a date we mutually agree to (see 10 CFR 2.108).

Peter S. Tam, Senior Project Manager Plant Licensing Branch III-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation e-mail: pst@nrc.gov Tel.: 301-415-1451 CC: Evan Davidson; James Tatum; Segala, John Mail Envelope Properties (4665C4BF.A8C : 12 : 35330)

Subject:

Monticello: Response to RAI re. Alternate Nitrogen System Pressure (TAC MD4292)

Creation Date 06/05/2007 4:17:03 PM From: Peter Tam Created By: PST@nrc.gov Recipients Action Date & Time nmcco.com Transferred 06/05/2007 4:17:15 PM Jesus.Arias (Jesus Arias)

Richard.Loeffler (Rick Loeffler) nrc.gov OWGWPO03.HQGWDO01 Delivered 06/05/2007 4:17:13 PM EJD1 CC (Evan Davidson) Opened 06/05/2007 4:17:16 PM nrc.gov TWGWPO02.HQGWDO01 Delivered 06/05/2007 4:17:05

PM JET1 CC (James Tatum) Opened 06/05/2007 4:17:44 PM JPS1 CC (John Segala) Opened 06/05/2007 4:18:16 PM Post Office Delivered Route nmcco.com OWGWPO03.HQGWDO01 06/05/2007 4:17:13 PM nrc.gov TWGWPO02.HQGWDO01 06/05/2007 4:17:05 PM nrc.gov Files Size Date & Time MESSAGE 2140 06/05/2007 4:17:03 PM Options Auto Delete: No Expiration Date: None Notify Recipients: Yes Priority: Standard ReplyRequested: No Return Notification: None Concealed

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