ML071020188

Request for Additional Information LPCI Loop Select Logic Amendment

ML071020188
Person / Time
Site:	Monticello
Issue date:	04/17/2007
From:	Tam P NRC/NRR/ADRO/DORL/LPLIII-1
To:	Conway J Nuclear Management Co
References
TAC MD4095
Download: ML071020188 (4)

Text

April 17, 2007 Mr. John T. Conway Site Vice President Monticello Nuclear Generating Plant Nuclear Management Company, LLC 2807 West County Road 75 Monticello, MN 55362-9637

SUBJECT:

MONTICELLO NUCLEAR GENERATING PLANT - REQUEST FOR ADDITIONAL INFORMATION RE: LOW PRESSURE COOLANT INJECTION SELECT LOGIC AMENDMENT (TAC NO. MD4095)

Dear Mr. Conway:

The Nuclear Regulatory Commission (NRC) staff is reviewing your application dated January 29, 2007, for the subject amendment. On April 3, 2007, the NRC staff transmitted a draft Request for Additional Information (RAI, publicly available at Accession No. ML070950045), and on April 12, 2007, the NRC staff discussed the draft RAI with your staff.

Enclosed please find the final RAI; except for editorial changes, it is identical in content to the draft RAI. Your staff agreed that you can provide your response by May 17, 2007, in order to support your requested amendment issuance date of June 25, 2007. Please feel free to contact me if you need clarification of the RAI.

Sincerely,

/RA/

Peter S. Tam, Senior Project Manager Plant Licensing Branch III-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-263

Enclosure:

RAI cc w/encl: See next page

April 17, 2007 Mr. John T. Conway Site Vice President Monticello Nuclear Generating Plant Nuclear Management Company, LLC 2807 West County Road 75 Monticello, MN 55362-9637

SUBJECT:

MONTICELLO NUCLEAR GENERATING PLANT - REQUEST FOR ADDITIONAL INFORMATION RE: LOW PRESSURE COOLANT INJECTION SELECT LOGIC AMENDMENT (TAC NO. MD4095)

Dear Mr. Conway:

The Nuclear Regulatory Commission (NRC) staff is reviewing your application dated January 29, 2007, for the subject amendment. On April 3, 2007, the NRC staff transmitted a draft Request for Additional Information (RAI, publicly available at Accession No. ML070950045), and on April 12, 2007, the NRC staff discussed the draft RAI with your staff.

Enclosed please find the final RAI; except for editorial changes, it is identical in content to the draft RAI. Your staff agreed that you can provide your response by May 17, 2007, in order to support your requested amendment issuance date of June 25, 2007. Please feel free to contact me if you need clarification of the RAI.

Sincerely,

/RA/

Peter S. Tam, Senior Project Manager Plant Licensing Branch III-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-263

Enclosure:

RAI cc w/encl: See next page DISTRIBUTION PUBLIC LPL3-1 r/f RidsNrrDorlLpl3-1 RidsNrrPMPTam RidsNrrLATHarris RidsAcrsAcnwMailCenter RidsNrrDirsltsb RidsOgcRp RidsRgn3MailCenter RidsNrrDorlDpr G. Singh P. Loeser Amendment Accession No.: ML071020188 OFFICE LPL3-1/PM LPL3-1/LA EICB/BC LPL3-1/BC NAME PTam THarris AHowe* LRaghavan DATE 4/12/07 4/12/07 4/3/07* 4/17/07

• RAI transmitted by memo of 4/3/07.

OFFICIAL RECORD COPY

REQUEST FOR ADDITION INFORMATION MONTICELLO NUCLEAR GENERATING PLANT DOCKET NO. 50-263 (1) The second paragraph of Section 5.3 of Enclosure 1, in part, states: The LPCI [Low Pressure Coolant Injection] loop select time delay relays have very specific functions which do not specifically relate to accident timing parameters, Analytical Limits are not readily apparent. In addition, the second paragraph of Section 5.2 states: In MODES 1, 2, and 3, operation of the LPCI loop select logic functions is required to ensure that no single failure can prevent successfully selecting the unbroken recirculation loop for LPCI injection. Since LPCI mode of the Residual Heat Removal system is one of the Emergency Core Cooling Systems, please provide the analyzed value of the time available to achieve successful LPCI injection so that the Nuclear Regulatory Commission (NRC) staff can determine that adequate margin is available in the setting of the time delay relays with or without loss of offsite power.

(2) LPCI injection flow will only take place when the reactor pressure reduces to a value below the pump shut-off head. From the licensees application, it is not clear as to how much time is available after the reactor steam dome pressure falls below the pump shut-off head and the LPCI flow has to be established. Please provide this information along with the basis of this information.

(3) Please advise the NRC staff of the setpoint methodology and the method used for calculating the setpoint.

(4) The second paragraph of Section 5.3 of Enclosure 1 states: The total of all the nominal time delay settings is 3 seconds, and does not approach the 15 seconds available for completion. Totaling the upper adjustment limit for the three time delay relays involved in LPCI loop selection adds up to a total time of 9 seconds, and does not approach the 15 second requirement. Please explain how the total time delay setting can be 3 seconds when the proposed allowable value time setting for the three relays are 2.97, 0.75, and 0.75 seconds. Please clarify the statement as needed to avoid confusion.

(5) The licensees response to Item 1 of Generic Letter (GL) 91-04 stated that, since there was no requirement in the custom Technical Specification to test the time delay feature, calibration data from surveillance or maintenance records was not available for the LPCI loop select logic time delay relays to directly establish their drift characteristics. Please provide justification for the drift values used for ETR14D3A relays. Also, please provide the nominal trip setpoint values of the time delay relays.

(6) In the response to Item 1 of GL 91-04, the licensee has assumed that percentage drift for ETR14D3A (range 0.15 to 3.0 seconds) and that of ETR143B (range 0.55 to 15 seconds) are the same. The adjustable time delay ranges for these relays are significantly different. Please provide the basis of this assumption, including any available data to support this assumption. In addition, the 92-day drift data have been extrapolated for use in 30 month drift calculation. Please provide the basis with the reference used for extrapolating the 92-day drift data to 30-month drift calculation.

Monticello Nuclear Generating Plant cc:

Jonathan Rogoff, Esquire Commissioner Vice President, Counsel & Secretary Minnesota Department of Commerce Nuclear Management Company, LLC 85 7th Place East, Suite 500 700 First Street St. Paul, MN 55101-2198 Hudson, WI 54016 Manager - Environmental Protection Division U.S. Nuclear Regulatory Commission Minnesota Attorney Generals Office Resident Inspector's Office 445 Minnesota St., Suite 900 2807 W. County Road 75 St. Paul, MN 55101-2127 Monticello, MN 55362 Michael B. Sellman Manager, Nuclear Safety Assessment President and Chief Executive Officer Monticello Nuclear Generating Plant Nuclear Management Company, LLC Nuclear Management Company, LLC 700 First Street 2807 West County Road 75 Hudson, MI 54016 Monticello, MN 55362-9637 Nuclear Asset Manager Commissioner Xcel Energy, Inc.

Minnesota Pollution Control Agency 414 Nicollet Mall, R.S. 8 520 Lafayette Road Minneapolis, MN 55401 St. Paul, MN 55155-4194 Regional Administrator, Region III U.S. Nuclear Regulatory Commission Suite 210 2443 Warrenville Road Lisle, IL 60532-4351 Commissioner Minnesota Department of Health 717 Delaware Street, S. E.

Minneapolis, MN 55440 Douglas M. Gruber, Auditor/Treasurer Wright County Government Center 10 NW Second Street Buffalo, MN 55313 November 2005