ML12131A001

G20120281/EDATS: OEDO-2012-0240 - Anthony R. Pietrangelo Ltr. Re Degraded Grid Voltage Protection Design and Configuration

ML12131A001
Person / Time
Site:	Nuclear Energy Institute
Issue date:	06/21/2012
From:	Mary Johnson NRC/EDO
To:	Pietrangelo A Nuclear Energy Institute
Andersen J, NRR/DE/EEEB, 415-3565
Shared Package
ML12129A349	List: ML12131A001
References
G20120281, OEDO-2012-0240, TAC ME8495
Download: ML12131A001 (2)

Text

June 21, 2012 Mr. Anthony R. Pietrangelo Senior Vice President and Chief Nuclear Officer Nuclear Energy Institute 1776 I Street, NW., Suite 400 Washington, DC 20006

Dear Mr. Pietrangelo:

On behalf of the U.S. Nuclear Regulatory Commission (NRC), I am responding to your April 12, 2012, letter (Agencywide Documents Access and Management System (ADAMS)

Accession No. ML12121A180) regarding concerns with degraded grid voltage protection design and configuration. Your letter stated that despite multiple attempts to bridge the perceived gaps in understanding between industry and NRC staff, you continue to be at an impasse on the operational impacts of the methods and expectations noted in the Regulatory Issue Summary (RIS) 2011-12, Revision 1, Adequacy of Station Electric Distribution System Voltages.

Further, you stated that you are seeking a consensus on an appropriate path forward to address your concerns.

The staff shares your interest in breaking the impasse, achieving consensus on issues of concern, and determining an appropriate path forward to ensure that emergency core cooling systems are adequately protected from degraded voltage conditions while maintaining operational safety and plant system reliability. Your letter asserted that the RIS went far beyond the general design criteria contained in General Design Criterion (GDC) 17 and is more appropriate for regulatory guidance. The staff notes that the positions described in the RIS are consistent with GDC 17 as further informed by other existing guidance in the standard review plan and previous generic communications. However, the staff agrees with the value of establishing consolidated guidance in a Regulatory Guide. The staff has been working toward that end through the Institute of Electrical and Electronic Engineers (IEEE) Standard 741 working group (Working Group 4.7 of IEEE Subcommittee SC-4, Auxiliary Power) to achieve consensus on the issues of concern and to establish appropriate resolution of those issues.

The staff remains committed to resolving the issues of concern with the goal of a staff endorsement of consensus guidance through a future Regulatory Guide.

Should you or your staff have any questions, please contact James Andersen of my staff at (301) 415-3565.

Sincerely,

/RA/

Michael R. Johnson Deputy Executive Director for Reactor and Preparedness Programs Office of the Executive Director for Operations

Mr. Anthony R. Pietrangelo Senior Vice President and Chief Nuclear Officer Nuclear Energy Institute 1776 I Street, NW., Suite 400 Washington, DC 20006

Dear Mr. Pietrangelo:

On behalf of the U.S. Nuclear Regulatory Commission (NRC), I am responding to your April 12, 2012, letter (Agencywide Documents Access and Management System (ADAMS)

Accession Number ML12121A180) regarding concerns with degraded grid voltage protection design and configuration. Your letter stated that despite multiple attempts to bridge the perceived gaps in understanding between industry and NRC staff, you continue to be at an impasse on the operational impacts of the methods and expectations noted in the Regulatory Issue Summary (RIS) 2011-12, Revision 1, Adequacy of Station Electric Distribution System Voltages. Further, you stated that you are seeking a consensus on an appropriate path forward to address your concerns.

The staff shares your interest in breaking the impasse, achieving consensus on issues of concern, and determining an appropriate path forward to ensure that emergency core cooling systems are adequately protected from degraded voltage conditions while maintaining operational safety and plant system reliability. Your letter asserted that the RIS went far beyond the general design criteria contained in General Design Criterion (GDC) 17 and is more appropriate for regulatory guidance. The staff notes that the positions described in the RIS are consistent with GDC 17 as further informed by other existing guidance in the standard review plan and previous generic communications. However, the staff agrees with the value of establishing consolidated guidance in a Regulatory Guide. The staff has been working toward that end through the Institute of Electrical and Electronic Engineers (IEEE) Standard 741 working group (Working Group 4.7 of IEEE Subcommittee SC-4, Auxiliary Power) to achieve consensus on the issues of concern and to establish appropriate resolution of those issues.

The staff remains committed to resolving the issues of concern with the goal of a staff endorsement of consensus guidance through a future Regulatory Guide.

Should you or your staff have any questions, please contact James Andersen of my staff at (301) 415-3565.

Sincerely,

/RA/

Michael R. Johnson Deputy Executive Director for Reactor and Preparedness Programs Office of the Executive Director for Operations DISTRIBUTION: G20120281/ EDATS: OEDO-2012-0240 RidsNrrMailCenter Resource RidsEdoMailCenter Resource RidsNrrOd Resource RidsNrrDeEeeb Resource RidsNrrDeEeeb Resource RidsOgcMailCenter Package Accession Number:: ML12129A349 *E-mail concurrence Incoming Accession Number: ML12121A180 Response: ML12131A001 OFFICE NRR/DE BC:NRR/DE Tech Editor* DD:NRR/DE OD: NRR OGC OEDO/DEDR NAME RMathew JAndersen CHsu PHiland ELeeds JBiggins MJohnson (DDorman for)

DATE 05/10/12 05/14/12 05/08/12 05/14/12 05/18/12 06/01/12 06/21/12 OFFICIAL RECORD COPY