BSEP 03-0106, Response to Request for Additional Information Core Flow Operating Range Expansion

Response to Request for Additional Information Core Flow Operating Range Expansion

ML031900219
Person / Time
Site:	Brunswick
Issue date:	07/02/2003
From:	Keenan J Progress Energy Carolinas
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
BSEP 03-0106, TAC MB6692, TAC MB6693, TSC-2002-09
Download: ML031900219 (4)

Text

John S. Keenan Brunswick Nuclear Plant Progress Energy Carolinas. Inc.

JUL 0 2 2003 SERIAL: BSEP 03-0106 TSC-2002-09 U. S. Nuclear Regulatory Commission ATITN: Document Control Desk Washington, DC 20555-0001

Subject:

Brunswick Steam Electric Plant, Unit Nos. 1 and 2 Docket Nos. 50-325 and 50-324l1icense Nos. DPR-71 and DPR-62 Response to Request for Additional Information Core Flow Operating Range Expansion (NRC TAC No. MB6692 and MB6693)

Reference:

Letter from Mr. John S. Keenan to the U. S. Nuclear Regulatory Commission (Serial: BSEP 02-0169), "Request for License Amendments -

Core Flow Operating Range Expansion," dated November 12, 2002 Ladies and Gentlemen:

On November 12, 2002, Progress Energy Carolinas, Inc. requested a revision to the Technical Specifications (TSs) for the Brunswick Steam Electric Plant (BSEP), Units 1 and 2. The proposed license amendments revise TSs, as necessary, to support an expansion of the core flow operating range (i.e., Maximum Extended Load Line Limit Analysis Plus (MELLLA+)).

On June 3, 2003, the NRC provided a verbal request for additional information (RAI) concerning the single recirculation loop operation setpoint for the Average Power Range Monitor Simulated Thermal Power - High scram function. The response to this RAI is enclosed.

Please refer any questions regarding this submittal to Mr. Edward T. ONeil, Manager - Support Services, at (910) 457-3512.

Sincerely, (hnS.K an PO. Box 10429 Southport, NC 28461 od T> 910.457.2496 F> 910.457.2803

Document Control Desk BSEP 03-0106 / Page 2 MAT/mat

Enclosure:

Response to Request for Additional Information (RAI) 3 John S. Keenan, having been first duly sworn, did depose and say that the information contained herein is true and correct to the best of his information, knowledge and belief; and the sources of his information are officers, employees, and agents of Carolina Power & Light Company.

Notary (Seal)

My commission expires: CX L)°2LO E+ , z cc:

U. S. Nuclear Regulatory Commission, Region II ATTN: Mr. Luis A. Reyes, Regional Administrator Sam Nunn Atlanta Federal Center 61 Forsyth Street, SW, Suite 23T85 Atlanta, GA 30303-8931 U. S. Nuclear Regulatory Commission ATTN: NRC Resident Inspector 8470 River Road Southport, NC 28461-8869 U. S. Nuclear Regulatory Commission (Electronic Copy Only)

AITN: Ms. Brenda L. Mozafari (Mail Stop OWFN 8G9) 11555 Rockville Pike Rockville, MD 20852-2738 Ms. Jo A. Sanford Chair - North Carolina Utilities Commission P.O. Box 29510 Raleigh, NC 27626-0510 Ms. Beverly 0. Hall, Section Chief Radiation Protection Section, Division of Radiation Protection North Carolina Department of Environment and Natural Resources 3825 Barrett Drive Raleigh, NC 27609-7221

BSEP 03-0106 Enclosure Page 1 of 2 Response to Request for Additional Information (RAI) 3

Background

On November 12, 2002, Progress Energy Carolinas, Inc. requested a revision to the Technical Specifications (TSs) for the Brunswick Steam Electric Plant (BSEP), Units 1 and 2. The proposed license amendments revise TSs, as necessary, to support an expansion of the core flow operating range (i.e., Maximum Extended Load Line Limit Analysis Plus (MELLLA+)).

On June 3, 2003, the NRC provided a verbal request for additional information (RAI) concerning the single recirculation loop operation setpoint for the Average Power Range Monitor Simulated Thermal Power - High scram function. The response to this RAI follows.

NRC Ouestion 3-1 In support of the licensee's MELLLA+ upgrade, the licensee referenced GE Nuclear Energy Report NEDC-33063P, "Safety Analysis Report for Brunswick Steam Electric Plant Units 1 and 2 Maximum Extended Load Line Limit Analysis Plus," dated November 2002 (M+SAR).

Section 5.3.1, "APRM Flow-biased Scram," stated, "MELLLA+ does not apply to single loop operation (SLO). Therefore, no SLO flow-biased expressions are provided." The licensee's proposed allowable value (AV) forTS Table 3.3.1.1-1, Function 2.b, Average Power Range Monitor Simulated Thermal Power - High (STP-Hi), is given by the equation

< 0.61W + 65.2% RTP and < 117.1% RTP Note (b) states,

• [0.61 (W - AW) + 65.2% RTP] when reset for single loop operation per LCO 3.4.1, "Recirculation Loops Operating." The Value of AW is defined in plant procedures.

Provide the basis for incorporating a MELLLA+ SLO flow-biased function in the TS that is not supported by the MELLLA+ licensing topical report (M+LTR) referenced in the licensee's submittal.

Response to NRC Question 3-1 As stated in Sections 1.2.4 and 5.3.1, Single Loop Operation (SLO) is prohibited when operating in the MELLLA+ region. This is reflected in the proposed change to Limiting Condition for Operation 3.4.1, "Recirculation Loops Operating," which states, in part:

One recirculation loop may be in operation provided the plant is not operating in the MELLLA+ region defined in the COLR...

BSEP 03-0106 Enclosure Page 2 of 2 The proposed change to the Allowable Value (AV) for Function 2.b of Table 3.3.1.1-1 does not alter the proposed change to LCO 3.4.1, rather it is a result of the existing design associated with the BSEP flow-biased scram function. Specifically, the BSEP flow-biased scram function has a fixed flow-biased slope. The proposed change to MELLLA flow-biased scram for SLO allows use of the same flow-biased slope as for the two loop operation scram for MELLLA+. The affect of the proposed change is to apply a more conservative setpoint for SLO than the previous MELLLA setpoint.