ML021290125

Issuance of Amendment Revision to Technical Specification for Oscillation Power Range Monitor Function, TAC No. MB2786

ML021290125
Person / Time
Site:	Fermi
Issue date:	05/24/2002
From:	Kim T NRC/NRR/DLPM/LPD3
To:	O'Connor W Detroit Edison
References
TAC MB2786
Download: ML021290125 (10)

Text

May 24, 2002 Mr. William T. OConnor, Jr.

Vice President - Nuclear Generation Detroit Edison Company 6400 North Dixie Highway Newport, MI 48166

SUBJECT:

FERMI, UNIT 2 - ISSUANCE OF AMENDMENT RE: REVISION TO TECHNICAL SPECIFICATION FOR OSCILLATION POWER RANGE MONITOR FUNCTION (TAC NO. MB2786)

Dear Mr. OConnor:

The Commission has issued the enclosed Amendment No. 146 to Facility Operating License No. NPF-43 for the Fermi, Unit 2, facility. The amendment consists of changes to the Technical Specifications (TSs) in response to your application dated August 24, 2001, as supplemented March 26, 2002.

The amendment revises the TSs to delete Required Action 3.3.1.1.J.2, which specifies that the oscillation power range monitor upscale trip function be restored to operable status within 120 days when it is determined to be inoperable.

A copy of our safety evaluation is also enclosed. The Notice of Issuance will be included in the Commission's biweekly Federal Register notice.

Sincerely,

/RA/

Tae Kim, Senior Project Manager, Section 1 Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-341

Enclosures:

1. Amendment No. 146 to NPF-43

2. Safety Evaluation cc w/encls: See next page

ML021290125 OFFICE PDIII-1/PM PDIII-1/LA SRXB/SC OGC PDIII-1/SC NAME TKim RBouling RCaruso RWeisman LRaghavan DATE 05/10/02 05/10/02 05/10/02 05/21/02 05/23/02 Fermi 2 cc:

Mr. Peter Marquardt Legal Department 688 WCB Detroit Edison Company 2000 2nd Avenue Detroit, MI 48226-1279 Drinking Water and Radiological Protection Division Michigan Department of Environmental Quality 3423 N. Martin Luther King Jr Blvd P. O. Box 30630 CPH Mailroom Lansing, MI 48909-8130 U.S. Nuclear Regulatory Commission Resident Inspectors Office 6450 W. Dixie Highway Newport, MI 48166 Monroe County Emergency Management Division 963 South Raisinville Monroe, MI 48161 Regional Administrator, Region III U.S. Nuclear Regulatory Commission 801 Warrenville Road Lisle, IL 60532-4351 Norman K. Peterson Director, Nuclear Licensing Detroit Edison Company Fermi 2 - 280 TAC 6400 North Dixie Highway Newport, MI 48166 March 2002

DETROIT EDISON COMPANY DOCKET NO. 50-341 FERMI, UNIT 2 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 146 License No. NPF-43

1. The Nuclear Regulatory Commission (the Commission) has found that:

A. The application for amendment by the Detroit Edison Company (the licensee) dated August 24, 2001, supplemented March 26, 2002, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commissions rules and regulations set forth in 10 CFR Chapter I; B. The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C. There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commissions regulations; D. The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E. The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commissions regulations and all applicable requirements have been satisfied.

2. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment and paragraph 2.C.(2) of Facility Operating License No. NPF-43 is hereby amended to read as follows:

Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A, as revised through Amendment No. 146, and the Environmental Protection Plan contained in Appendix B, are hereby incorporated in the license. DECo shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.

3. This license amendment is effective as of its date of issuance and shall be implemented within 30 days of the date of issuance.

FOR THE NUCLEAR REGULATORY COMMISSION

/RA/

L. Raghavan, Chief, Section 1 Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation

Attachment:

Changes to the Technical Specifications Date of Issuance: May 24, 2002

ATTACHMENT TO LICENSE AMENDMENT NO. 146 FACILITY OPERATING LICENSE NO. NPF-43 DOCKET NO. 50-341 Replace the following pages of the Appendix A Technical Specifications with the attached revised pages. The revised pages are identified by amendment number and contain marginal lines indicating the areas of change.

REMOVE INSERT 3.3.3 3.3.3 B 3.3.1.1-25 B 3.3.1.1-25 B 3.3.1.1-25a B 3.3.1.1-25a

SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 146 FACILITY OPERATING LICENSE NO. NPF-43 DETROIT EDISON COMPANY FERMI, UNIT 2 DOCKET NO. 50-341

1.0 INTRODUCTION

By application dated August 24, 2001, as supplemented March 26, 2002, the Detroit Edison Company (the licensee) requested changes to the Technical Specifications (TSs) for Fermi 2.

The proposed amendment would revise the TSs to delete Required Action 3.3.1.1.J.2, which specifies that the oscillation power range monitor upscale trip function be restored to operable status within 120 days when it is determined to be inoperable.

The March 26, 2002, supplemental letter provided additional clarifying information that was within the scope of the original application and did not change the staffs initial proposed no significant hazards consideration determination.

2.0 BACKGROUND

In the current TSs, Required Actions 3.3.1.1.J.1 and 3.3.1.1.J.2 specify actions to be taken in the event that the oscillation power range monitor (OPRM) upscale trip function (Function 2.f in the TS Table 3.3.1.1-1, Reactor Protection System Instrumentation) is found to be inoperable.

Required Action 3.3.1.1.J.1 specifies that an alternate method to detect and suppress thermal hydraulic instability oscillations be initiated within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> in the event that the OPRM upscale trip function is found to be inoperable. Required Action 3.3.1.1.J.2 specifies that the OPRM upscale trip function be restored to operable status within 120 days. If the OPRM upscale trip function cannot be restored to operable status within the required 120 days, then TS 3.3.1.1.K.1 requires that reactor thermal power be reduced to less than 25 percent within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. The proposed changes would delete Required Action 3.3.1.1.J.2 which specifies that the OPRM upscale trip function be restored to operable status within 120 days.

The OPRM upscale trip function is designed to detect and suppress possible reactor thermal hydraulic instabilities. The OPRM module of the General Electric (GE) power range neutron monitoring (PRNM) system was installed at Fermi 2 in accordance with Option III in NEDO-31960, Supplement 1, BWR [Boiling Water Reactor] Owners Group [BWROG]

Long-Term Stability Solution Licensing Methodology, dated November 1995. TS changes for the installation of the PRNM system and subsequent arming of the OPRM system were reviewed and approved by the Nuclear Regulatory Commission (NRC), as documented in safety evaluation reports dated July 13, 1998, and March 31, 2000, respectively.

Prior to the installation and arming of the OPRM, monitoring for thermal-hydraulic instability oscillations, and suppression thereof, was performed exclusively by operating procedures.

These operator stability monitoring functions are commonly referred to in the industry as interim corrective actions (ICAs) and are the same actions referenced in existing Required Action 3.3.1.1.J.1 for the situation in which the OPRM trip capability is lost. In summary, the stability ICAs, which are implemented in plant procedures, prescribe that (1) reactor stability be monitored through instrumentation whenever the plant is operating in the power/flow map regions associated with potential stability concerns and (2) specific actions be taken in the event an instability condition is observed or is likely.

The licensee stated in its March 26, 2002, supplemental letter that the OPRM system was armed and declared operable in May 2000 during the startup following the 7th refueling outage.

According to the licensee, the system did not experience any difficulty until it was declared inoperable on June 27, 2001, as a result of GEs notification to the licensee of a potential condition associated with a potentially nonconservative calculation of the OPRM trip setpoints for the operating cycle (Cycle 8). For Fermi 2, these calculations are defined in Licensing Topical Report NEDO-32465-A, Reactor Stability Detect and Suppress Solutions Licensing Basis Methodology for Reload Applications, dated August 1996. This report specifies two generic curves (Delta Critical Power Ratio/Initial Critical Power Ratio vs. Oscillation Magnitude (DIVOM curves)), one for core-wide mode oscillations and one for regional mode oscillations, relating normalized critical power ratio to hot bundle oscillation magnitude. In Option III, the generic regional mode curve is used to determine setpoints for the OPRM system to provide adequate safety limit minimum critical power ratio (SLMCPR) protection. GEs notification to the licensee identified a nonconservative deficiency for high peak bundle power-to-flow ratios in the generic regional DIVOM curve. As a result, the OPRM system trip setpoint may be overpredicted by the generic regional DIVOM curve. Formal notification on the same subject was provided to the NRC by a letter from GE dated June 29, 2001. The net effect of this condition is the possible generation and implementation of nonconservative OPRM upscale trip setpoints that could result in inadequate SLMCPR protection during a reactor thermal-hydraulic instability event.

By declaring the OPRM system inoperable, the licensee entered TS 3.3.1.1.J, which invokes the alternate instability monitoring action statement and the 120-day requirement to return the OPRM system to operable status. The licensee stated that it received confirmation from GE on July 5, 2001, that this issue was applicable to Cycle 8 at Fermi 2. Subsequently, based on the Figure of Merit value provided to GE by the licensee, GE provided an interim DIVOM curve slope that was more conservative than the generic DIVOM curve for regional mode oscillations contained in NEDO-32465-A. Based on this interim DIVOM curve slope, the licensee calculated an interim OPRM trip setpoint for the remainder of Cycle 8 (which ended on October 27, 2001), and the OPRM system was declared operable on August 17, 2001. The licensee noted that the interim OPRM trip setpoint was calculated to be the same as that already implemented in the OPRM system, so no physical setpoint change was necessary.

This was attributed to the conservatism that already existed in the initial Cycle 8 OPRM trip setpoint. For the current operating cycle (Cycle 9), a conservative Figure of Merit value was again calculated by the licensee based on the BWROG guidance. GE subsequently determined an appropriate interim DIVOM curve slope to use in the standard reload licensing calculation of the OPRM trip setpoint for Cycle 9. The resulting Cycle 9 OPRM interim trip setpoint was determined to be the same as that used in Cycle 8, thus maintaining the OPRM system operable in Cycle 9.

3.0 EVALUATION The licensee requested a change to the Fermi, Unit 2, TSs in accordance with the 10 CFR 50.90. The licensee proposed to delete Required Action 3.3.1.1.J.2, which requires restoration of required channels to OPERABLE status, with a completion time of 120 days.

The licensees justifications for deleting Required Action 3.3.1.1.J.2 are provided below:

1. Required Action 3.3.1.1.J.1 allows a completion time of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> to initiate an alternate method to detect and suppress thermal-hydraulic instability oscillations;

2. The alternate ICA function is maintained in TSs, plant procedures, and operator training; and

3. Problems with the OPRM system will continue to be required to be remedied in a timely manner in accordance with 10 CFR Part 50, Appendix B, Criterion XVI, Corrective Action.

The NRC staff has reviewed the licensees justifications for deleting Required Action 3.3.1.1.J.2, and has found it acceptable for the following reason: Both the ICAs and the Commissions regulation, 10 CFR Part 50, Appendix B, Criterion XVI, will apply when the OPRM system is inoperable. Criterion XVI requires prompt identification and corrective action if the OPRM system is inoperable, and together with the ICAs, will provide reasonable assurance that core thermal-hydraulic oscillations will be prevented, detected, and suppressed.

4.0 STATE CONSULTATION

In accordance with the Commission's regulations, the Michigan State official was notified of the proposed issuance of the amendment. The State official had no comments.

5.0 ENVIRONMENTAL CONSIDERATION

The amendment changes a requirement with respect to the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration and there has been no public comment on such finding (66 FR 59503). Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.

6.0 CONCLUSION

The Commission has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commissions regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

Principal Contributor: T. Huang Date: May 24, 2002