ML051710609

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U.S. Nuclear Regulatory Commission Response Regarding Nuclear Energy Institute 04-06, Guidance for Self-Assessment of Circuit Failure Issues
ML051710609
Person / Time
Issue date: 09/02/2005
From: Lyons J
Division of Systems Safety and Analysis
To: Marion A
Nuclear Energy Institute
Frumkin, d., NRR/DSSA/SPLB, 415-2280
References
RIS-04-003, Rev. 1
Download: ML051710609 (4)


See also: RIS 2004-03

Text

September 2, 2005

Mr. Alexander Marion

Senior Director, Engineering

Nuclear Generation Division

Nuclear Energy Institute

1776 I Street, NW, Suite 400

Washington, D.C. 20006-3708

SUBJECT:

U.S. NUCLEAR REGULATORY COMMISSION RESPONSE REGARDING

NUCLEAR ENERGY INSTITUTE 04-06, GUIDANCE FOR SELF-ASSESSMENT

OF CIRCUIT FAILURE ISSUES

Dear Mr. Marion:

On March 16, 2005, you submitted Revision L of Nuclear Energy Institute (NEI) 04-06,

Guidance for Self-Assessment of Circuit Failure Issues (ADAMS Accession No. ML050760219).

The staff supports the industry's efforts to standardize the self-evaluations related to circuit

failure issues.

The enclosure to this letter provides our specific comments to NEI 04-06. In particular,

licensees that perform NEI 04-06 may identify non risk-significant configurations which are not

in compliance with their plant licensing basis. Such non-compliances must be resolved in a

timely fashion and in accordance with NRC regulations. Also, we would like to reiterate that

Regulatory Issue Summary (RIS) 2004-003, Revision 1, does not differentiate between required

and associated circuits.

We thank you for your assistance in improving licensees understanding of the need for circuit

failure evaluation. Please contact Dr. Sunil Weerakkody or Mr. Daniel Frumkin of my staff if

you have additional questions on this matter.

Sincerely,

/RA/

James E. Lyons, Director

Division of Systems Safety and Analysis

Office of Nuclear Reactor Regulation

Enclosure: As stated

ML050760219).

The staff supports the industry's efforts to standardize the self-evaluations related to circuit

failure issues.

The enclosure to this letter provides our specific comments to NEI 04-06. In particular,

licensees that perform NEI 04-06 may identify non risk-significant configurations which are not

in compliance with their plant licensing basis. Such non-compliances must be resolved in a

timely fashion and in accordance with NRC regulations. Also, we would like to reiterate that

Regulatory Issue Summary (RIS) 2004-003, Revision 1, does not differentiate between required

and associated circuits.

We thank you for your assistance in improving licensees understanding of the need for circuit

failure evaluation. Please contact Dr. Sunil Weerakkody or Mr. Daniel Frumkin of my staff if

you have additional questions on this matter.

Sincerely,

/RA/

James E. Lyons, Director

Division of Systems Safety and Analysis

Office of Nuclear Reactor Regulation

Enclosure: As stated

DISTRIBUTION:

ADAMS

SPLB R/A

TMartin

JHannon

SWeerakkody

DFruchter

PKoltay

PQualls

RGallucci

DFrumkin

STreby

RGibbs

CPatel

ADAMS Accession # ML051710609

NRR-106

OFFICE

SPLB/DSSA/NRR

SC:SPLB/DSSA/NRR

BC:SPLB/DSSA/NRR

SC:IIPB/DIPM/NRR

NAME

DFrumkin

SWeerakkody

JHannon

RGibbs

DATE

06 / 27 /05

07 / 03 /05

07 / 07 /05

07 / 29 /05

OFFICE

OGC

D:DSSA/NRR

NAME

STreby

JLyons

DATE

08 / 17 /05

09 / 02 /05

ENCLOSURE

NRC COMMENTS REGARDING THE NEI 04-06, GUIDANCE FOR SELF-ASSESSMENT FOR

CIRCUIT FAILURE ISSUES

NRC staff comments are provided below.

1. Page 1, fourth paragraph. The guidance in NEI 04-06 does not assess compliance with a

plant's licensing basis and applicable rules. Licensing bases are plant specific and must be

assessed against plant specific license basis documents.

2. Page 1, fourth paragraph states, As an example, providing 20' of separation between

redundant trains with no intervening combustibles is an acceptable method for

compliance . . .. Twenty feet of separation without intervening combustibles also requires

detection and automatic suppression.

3. Page 3, first paragraph. Delete required and associated since Regulatory Issue Summary

(RIS) 2004-03, Rev. 1 does not use these terms. Make this change throughout the

document.

4. Page 3, second paragraph, Section 2.2. Note that although the assumption of the

consideration of a maximum of two concurrently damaged cables is consistent with RIS 2004-03, Rev. 1, it may not be consistent with a plants specific licensing basis. The NRC

will use the plants licensing basis for determining compliance.

5. Page 3, Intent of Screening process. The intent must comply with the licensing bases of

the facility. Even violations that are screened to green or are minor that are identified

through this process are violations and must be identified and addressed.

6.

Page 5, Section 3.2 paragraph 1. Identify the . . . that could significantly impact. Delete

the word significantly, since limiting identification findings to a judgement of what are

significant does not comply with the regulation.

7. Figure A-1 (on page 25) allows screening with 20' separation. It should also mention

detection and automatic suppression.

8. Figure A-1 (on page 56) Should not allow screening low risk issues without compliance

with regulations.

9. Appendix B. This appendix is devoted to required and associated circuits. The RIS that

this document implements does not use these terms. Rather the RIS relates only to failures

that could adversely affect safe shutdown, regardless of how they are classified. Therefore,

the judgments in this appendix are not consistent with the RIS and should be deleted. Also,

based on the technical basis of the appendix, the staff has issues with the determinations

(see NRC comments dated 4/27/2004, ADAMS Accession No. ML042270373).

10. Appendix C, Template. This template makes a distinction between required and associated

circuits. RIS 2004-03, Rev. 1, does not make this distinction.