ML100550903
| ML100550903 | |
| Person / Time | |
|---|---|
| Site: | Boiling Water Reactor Owners Group |
| Issue date: | 03/01/2010 |
| From: | Rosenberg S NRC/NRR/DPR/PSPB |
| To: | Schiffley F Exelon Generation Co |
| References | |
| Download: ML100550903 (4) | |
Text
March 1, 2010 Frederick (Ted) Schiffley BWROG, Chairman Exelon Generation Co., LLC.
Cornerstone II at Cantera 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
THE USE OF CONTAINMENT ACCIDENT PRESSURE IN DEMONSTRATING ACCEPTABLE OPERATION OF EMERGENCY CORE COOLING AND CONTAINMENT HEAT REMOVAL PUMPS DURING POSTULATED ACCIDENTS
Dear Mr. Schiffley:
U.S. Nuclear Regulatory Commission (NRC) licensees, including many licensees operating boiling water reactors (BWRs), have included the use of containment accident pressure in demonstrating acceptable operation of emergency core cooling system (ECCS) and containment heat removal pumps during postulated accidents.
The NRC staff has undertaken a review of this issue including current NRC staff guidance. The NRC staff has also informed two licensees that we will delay completion of their proposed extended power uprate reviews until this review is complete.
The NRC staff has discussed this issue on several occasions with the Advisory Committee on Reactor Safeguards (ACRS). The ACRS has, in turn, discussed this issue with the Commission at several recent meetings. The NRC staff has carefully considered the ACRS recommendations contained in a March 18, 2009, letter to the NRC Executive Director for Operations in our review.
The NRC staff has now completed the first phase of this review. We have identified those issues important to this subject and are proposing draft guidance. Some of this guidance is consistent with current guidance and some has not previously been discussed with the industry.
The purpose of this letter is to provide you with the results of our re-examination of this issue in order to initiate a technical dialogue with the BWROG. The goal is to formulate final guidance on the basis of the best available data and analyses, which will be documented in a regulatory guide and serve as guidance to the industry and NRC staff reviewers. In formulating this draft guidance, we have used information currently available to the NRC staff. We anticipate that the BWROG, perhaps with the assistance of pump suppliers, will be able to provide additional information. This is most important in several areas that have not been included in previous staff/industry discussions. This includes the explicit use of uncertainty.
We have enclosed a draft report, entitled "NRC Draft Guidance for the Use of Containment Accident Pressure in Determining the NPSH [Net Positive Suction Head] Margin of ECCS and Containment Heat Removal Pumps," for your review. The report is also available in the Agencywide Document Access and Management System under Accession Number ML100550869. We request that you examine this draft report and that you then discuss the report with us. A public meeting would be most appropriate.
If you have questions regarding this matter, please contact Michelle C. Honcharik on (301) 415-1774.
Sincerely,
/RA/
Stacey L. Rosenberg, Chief Licensing Processes Branch Division of Policy and Rulemaking Office of Nuclear Reactor Regulation Project No. 691
Enclosure:
As stated cc: See next page
We have enclosed a draft report, entitled "NRC Draft Guidance for the Use of Containment Accident Pressure in Determining the NPSH [Net Positive Suction Head] Margin of ECCS and Containment Heat Removal Pumps," for your review. The report is also available in the Agencywide Document Access and Management System under Accession Number ML100550869. We request that you examine this draft report and that you then discuss the report with us. A public meeting would be most appropriate.
If you have questions regarding this matter, please contact Michelle C. Honcharik on (301) 415-1774.
Sincerely,
/RA/
Stacey L. Rosenberg, Chief Licensing Processes Branch Division of Policy and Rulemaking Office of Nuclear Reactor Regulation Project No. 691
Enclosure:
As stated cc: See next page DISTRIBUTION:
PUBLIC PSPB Reading File RidsNrrDpr RidsNrrDprPspb RidsNrrLADBaxley RidsAcrsAcnwMailCenter RidsNrrPMMHoncharik RidsOgcMailCenter RidsNrrDssSvcb (Robert Dennig)
RidsNrrDss Richard Lobel Ahsan Sallman SRosenberg (Hardcopy)
ADAMS ACCESSION NO.: Package ML100560025 Cover letter ML100550903 Enclosure ML100550869 NRR-106 OFFICE PLPB/PM PLPB/LA SCVB/BC DSS/D PLPB/BC NAME MHoncharik DBaxley (EHylton for)
RDennig WRuland SRosenberg DATE 2/26/10 2/26/10 3/1/10 3/1/10 3/1/10 OFFICIAL RECORD COPY
02/3/10 BWR Owners= Group Project No. 691 Mr. Oscar Limpias BWROG, Executive Chairman Entergy Nuclear 1340 Echelon Parkway.
Jackson, MS 39213-8202 olimpia@entergy.com Paul J. Davison BWROG, Executive Vice Chairman Hope Creek Generating Station P.O. Box 236 Hancocks Bridge, NJ 08038 paul.davison@pseg.com Mr. Dennis Madison Hatch Vice President Southern Nuclear Operating Co.
11028 Hatch Parkway North Baxley, GA 31515-2010 drmadiso@southernco.com Mr. James F. Klapproth GE-Hitachi Nuclear Energy M/C A50 3901 Castle Hayne Road Wilmington, NC 28401 james.klapproth@ge.com Mr. Michael Crowthers BWROG, Vice Chairman PPL Susquehanna, LLC 2 North Ninth Street Allentown, PA 18101-1179 mhcrowthers@pplweb.com Mr. Douglas Coleman Chairman, Regulatory Response Group Energy Northwest Columbia Generating Station Mail Drop PE20 P.O. Box 968 Richland, WA 99352-0968 dwcoleman@energy-northwest.com Mr. Craig J. Nichols BWROG, Program Manager GE-Hitachi Nuclear Energy PO Box 780 M/C F12 3901 Castle Hayne Road Wilmington, NC 28402 craig.nichols@ge.com