ML060440613

Y020060034 - Request for Information Concerning the Mark I BWR Delta-P Method Used to Design and Operate Nuclear Power Plants

ML060440613
Person / Time
Site:	Grand Gulf
Issue date:	02/14/2006
From:	Boger B A NRC/NRR/ADRO
To:	Humphrey J M - No Known Affiliation
DUDLEY N, NRR, 415-1145
Shared Package
ML060530276	List: ML060440613 ML060470374
References
TAC MD0041, Y020060034
Download: ML060440613 (3)

Text

February 14, 2006Mr. John M. Humphrey25967 Mar Vista Court Los Gatos, CA 95033

SUBJECT:

REQUEST FOR INFORMATION CONCERNING THE MARK I BWR DELTA-PMETHOD USED TO DESIGN AND OPERATE NUCLEAR POWER PLANTSIn response to your letter dated January 16, 2006, the NRC staff collected informationconcerning the use of the differential pressure between the drywell and the suppressionchamber of Mark I containments. Several BWR/3 and BWR/4 reactors with Mark I containments are still operating. The enclosed 2004-2005 Edition of the United States NuclearRegulatory Commission Information Digest contains a list of the operating nuclear reactors in the United States. The list also includes the type of containment used for each reactor. The standard technical specifications (STS) for BWR/4 reactors includes a limitingcondition for operations based on the drywell-to-suppression chamber differential pressure. If the differential pressure is not maintained, the reactor power is required to be reduced below 15%. A page from the BWR/4 STS is provided as attachment 1.

The STSs for different types of reactors are available on the world-wide web at http://www.nrc.gov/reactors/operating/licensing/techspecs/current-approved-sts.html.I note that you also had an interest in Mark III BWR containment response. One of our moreexperienced staff members recognized your name and remembered that the Grand Gulf Updated Final Safety Analysis Report (UFSAR), contains responses to "Humphrey Issues." contains selected UFSAR pages that refer to "Humphrey Issues."As you can see, the Mark I BWR drywell-to-suppression chamber differential pressure hasbeen and continues to be used in the safe operations and regulation of nuclear power plants.

Thank you for your contributions over the last 30 years in ensuring that the use of nuclearpower is conducted in a manner that protects public health and safety, and the environment.Sincerely,/RA/

Bruce Boger, Associate Director for Operating Reactor Oversight and Licensing Office of Nuclear Reactor Regulation

Attachment:

1. Standard Technical Specifications General Electric Plants, BWR/42. Grand Gulf Nuclear Station, Updated Final Analysis Report

Enclosure:

2004-2005 Edition of the United States Nuclear Regulatory CommissionInformation Digest Mr. John M. Humphrey25967 Mar Vista Court Los Gatos, CA 95033

SUBJECT:

REQUEST FOR INFORMATION CONCERNING THE MARK I BWR DELTA-PMETHOD USED TO DESIGN AND OPERATE NUCLEAR POWER PLANTSIn response to your letter date January 16, 2006, the NRC staff collected informationconcerning the use of the differential pressure between the drywell and the suppressionchamber of Mark I containments. Several BWR/3 and BWR/4 reactors with Mark I containments are still operating. The enclosed 2004-2005 Edition of the United States NuclearRegulatory Commission Information Digest contains a list of the operating nuclear reactors in the United States. The list also includes the type of containment used for each reactor. The standard technical specifications (STS) for BWR/4 reactors includes a limitingcondition for operations based on the drywell-to-suppression chamber differential pressure. If the differential pressure is not maintained, the reactor power is required to be reduced below 15%. A page from the BWR/4 STS is provided as attachment 1.

The STSs for different types of reactors are available on the world-wide web at http://www.nrc.gov/reactors/operating/licensing/techspecs/current-approved-sts.html.One of our more experienced staff members recognized your name and remembered that theGrand Gulf Updated Final Safety Analysis Report (UFSAR), contains responses to "Humphrey Issues." Attachment 2 contains selected UFSAR pages that refer to "Humphrey Issues."As you can see, the Mark I BWR drywell-to-suppression chamber differential pressure hasbeen and continues to be used in the safe operations and regulation of nuclear power plants.

Thank you for your contributions over the last 30 years in ensuring that the use of nuclearpower is conducted in a manner that protects public health and safety and the environment.Sincerely,/RA/Bruce Boger, Associate Director for Operating Reactor Oversight and Licensing Office of Nuclear Reactor Regulation

Attachment:

1. Standard Technical Specifications General Electric Plants, BWR/42. Grand Gulf Nuclear Station, Updated Final Analysis Report

Enclosure:

2004-2005 Edition of the United States Nuclear Regulatory CommissionInformation Digest E:\Filenet\ML060440613.wpd pkg# - ML060530276, memo - ML060440613, attach 1 -ML032720559, attach 2 - ML060110092, attach 3 - ML042360006OFFICENRR/ADRO/TANRR/ADRONAMENDudleyBABogerDATE 2/ 7/062/ 14 /06 OFFICIAL RECORD COPY