ML041980010

Emergency Response Capability - Conformance to NRC Regulatory Guide 1.97, Revision 2

ML041980010
Person / Time
Site:	Duane Arnold
Issue date:	07/22/2004
From:	David Beaulieu NRC/NRR/DLPM/LPD3
To:	Peifer M Nuclear Management Co
Beaulieu, David, NRR/DLPM, 415-3243
References
RG-1.097, TAC MC0748
Download: ML041980010 (4)

Text

07/22/04 Mark A. Peifer Site Vice President Duane Arnold Energy Center Nuclear Management Company, LLC 3277 DAEC Road Palo, IA 52324-0351

SUBJECT:

DUANE ARNOLD ENERGY CENTER - EMERGENCY RESPONSE CAPABILITY - CONFORMANCE TO NRC REGULATORY GUIDE 1.97, REVISION 2 (TAC NO. MC0748)

Dear Mr. Peifer:

By letter dated September 12, 2003, Nuclear Management Company, LLC (NMC) requested U.S. Nuclear Regulatory Commission (NRC) approval of a deviation from NRC Regulatory Guide 1.97, Revision 2, "Instrumentation for Light-Water-Cooled Nuclear Power Plants to Assess Plant and Environs Conditions During and Following an Accident," for the instrumentation that monitors standby liquid control system flow at the Duane Arnold Energy Center.

The NRC staff has evaluated the above request and finds that the NMC has provided adequate justification for its proposed deviation from NRC Regulatory Guide 1.97. Enclosed is our Safety Evaluation Report.

If you have any questions regarding this matter, I may be reached at 301-415-3243.

Sincerely,

/RA/

David P. Beaulieu, Project Manager, Section 1 Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-331

Enclosure:

Safety Evaluation Report cc w/encl: See next page

ML041980010 OFFICE PDIII-1/PM PDIII-1/LA PDIII-1/SC NAME DBeaulieu THarris LRaghavan DATE 07/22/04 07/20/04 07/22/04 Duane Arnold Energy Center cc:

Mr. John Paul Cowan Daniel McGhee Executive Vice President & Utilities Division Chief Nuclear Officer Iowa Department of Commerce Nuclear Management Company, LLC Lucas Office Buildings, 5th floor 700 First Street Des Moines, IA 50319 Hudson, MI 54016 Chairman, Linn County John Bjorseth Board of Supervisors Plant Manager 930 1st Street SW Duane Arnold Energy Center Cedar Rapids, IA 52404 3277 DAEC Road Palo, IA 52324 Craig G. Anderson Senior Vice President, Group Operations Steven R. Catron 700 First Street Manager, Regulatory Affairs Hudson, WI 54016 Duane Arnold Energy Center 3277 DAEC Road Palo, IA 52324 U.S. Nuclear Regulatory Commission Resident Inspectors Office Rural Route #1 Palo, IA 52324 Regional Administrator, Region III U.S. Nuclear Regulatory Commission 2443 Warrenville Road, Suite 210 Lisle, IL 60532-4352 Jonathan Rogoff Vice President, Counsel & Secretary Nuclear Management Company, LLC 700 First Street Hudson, WI 54016 Bruce Lacy Nuclear Asset Manager Alliant Energy/Interstate Power and Light Company 3277 DAEC Road Palo, IA 52324

SAFETY EVALUATION REPORT BY THE OFFICE OF NUCLEAR REACTOR REGULATION CONFORMANCE TO REGULATORY GUIDE 1.97 NUCLEAR MANAGEMENT COMPANY, LLC DUANE ARNOLD ENERGY CENTER DOCKET NO. 50-331

1.0 INTRODUCTION

By letter dated September 12, 2003, (ML032730547) Nuclear Management Company, LLC (NMC) identified a deviation from U. S. Nuclear Regulatory Commission (NRC) Regulatory Guide (RG) 1.97, Revision 2, "Instrumentation for Light-Water-Cooled Nuclear Power Plants to Assess Plant and Environs Conditions During and Following an Accident," for the instrumentation that monitors standby liquid control system (SLCS) flow for the Duane Arnold Energy Center (DAEC). The proposed deviation would change the SLCS flow instrumentation from a key variable to a backup variable and thus change the instrumentation from Category 2 to Category 3 as defined in NRC RG 1.97.

2.0 REGULATORY EVALUATION

The primary purpose of post accident monitoring instrumentation is to display plant variables that provide information required by the control room operator during accident situations. This information provides the necessary support for the operator to take manual actions to initiate safety systems and other appropriate systems important to safety. NRC RG 1.97 states that a key variable for system operating status is that single variable (or minimum set of variables) that most directly indicates the operation of a safety system and recommends the use of instrumentation that meets the Category 2 criteria. NRC RG 1.97 also recommends the use of instrumentation that meets the Category 3 criteria for instrumentation that provides system operating status backup or diagnostic information.

The Category 2 criteria includes the recommendation that Category 2 instrumentation be environmentally qualified in accordance with NRC RG 1.89, "Environmental Qualification of Certain Electrical Equipment Important to Safety for Nuclear Power Plants." The Category 3 criteria does not include this recommendation.

3.0 TECHNICAL EVALUATION

NRC RG 1.97 recommends that Category 2 instrumentation be provided to monitor SLCS flow to provide the operator with information concerning the operation of SLCS during and after an accident. In the May 9, 1990, safety evaluation (ML9005160131), the staff accepted the instrumentation supplied for this variable based on the licensees May 3, 1989, letter (ML8905150106) that stated the SLCS flow instrumentation was located in a mild environment and that it met the Category 2 criteria. In its September 12, 2003, letter, NMC stated that they subsequently determined that this area is potentially harsh for radiation to certain electronic components. Because the existing SLCS flow instrumentation contains electronics that are sensitive to radiation, it is not qualified under the DAEC Environmental Qualification program and, therefore, does not meet the Category 2 criteria.

In its September 12, 2003, letter, NMC stated that because the design-basis mission of SLCS is to inject a specified quantity of sodium pentaborate into the reactor at 660 parts per million of boron, SLCS tank level is the "key variable," not SLCS flow rate. DAEC complies with the NRC RG 1.97 requirement for Category 2 instrumentation for SLCS tank level indication. Therefore, NMC has proposed that SLCS flow indication at the DAEC be designated as a "backup variable" under NRC RG 1.97 and qualified to Category 3 requirements. The existing SLCS flow instrumentation meets Category 3 requirements. NMCs submittal also notes that SLCS pump running indicator lights and SLCS pump discharge pressure also provide indication of SLCS operation.

The SLCS flow instrumentation provides indication that flow is occurring. Flow can also be determined using the Category 2 SLCS tank level instrumentation by observing a decrease in SLCS tank level. Other indications of SLCS system operation that are available to operators in the control room are the SLCS pump running indicator lights and SLCS pump discharge pressure. Therefore, the staff finds the use of Category 3 SLCS flow instrumentation is an acceptable alternative to the NRC RG 1.97 recommended Category 2 SLCS flow instrumentation.

4.0 CONCLUSION

Based on review of NMCs submittal, the staff finds that NMC has provided adequate justification for the deviation from the NRC RG 1.97, Revision 2, recommendations for the instrumentation that monitors SLCS flow at DAEC.

Principal Contributor: Barry S. Marcus