ML041490103
| ML041490103 | |
| Person / Time | |
|---|---|
| Site: | LaSalle  |
| Issue date: | 06/01/2004 |
| From: | Pickett D NRC/NRR/DLPM/LPD3 |
| To: | Crane C Exelon Generation Co |
| Pickett , NRR/DLPM, 415-1364 | |
| References | |
| Download: ML041490103 (5) | |
Text
June 1, 2004 Mr. Christopher M. Crane, President and Chief Nuclear Officer Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
LASALLE COUNTY STATION, UNIT NO. 2 - FINAL ACCIDENT SEQUENCE PRECURSOR ANALYSIS OF SEPTEMBER 2001 OPERATIONAL EVENT
Dear Mr. Crane:
Enclosed for your information is the final Accident Sequence Precursor (ASP) analysis of an adverse condition which was identified at the LaSalle County Station, Unit No. 2 in September 2001. The condition involved a reactor scram due to an undervoltage protective circuit actuation on a Division 1 engineered safety feature bus and is described in LER 374/01-003, dated October 25, 2001. The results of the final ASP analysis indicate that this condition is an accident precursor (i.e., a condition which results in a conditional core damage probability (CCDP) > 1E-6).
The risk significance associated with this event was not analyzed under the Significance Determination Process.
The findings in the ASP analysis (CCDP and dominant risk contributors) are consistent with those in the licensees risk analysis. This ASP analysis is being issued as a final product for information only. In the past, preliminary versions of all ASP analyses were issued for internal peer review by the NRC staff and for external peer review by the licensee. Comments received from these reviews were then resolved as part of the final analysis. To increase efficiency, we are now issuing the noncontroversial ASP analyses as final documents.
The NRC staff is continuing to review the appropriate classification of these documents within our records management program, considering changes in our practices following the events of September 11, 2001. Pending a final determination, the enclosed analyses have been marked as sensitive information. Therefore, the staff has not made it publicly available. Please control
C. Crane the document accordingly. We will inform you if the classification of the document changes as a result of our ongoing assessments.
Please contact me at 301-415-1364 if you have any questions regarding the enclosure.
Sincerely,
/RA/
Douglas V. Pickett, Senior Project Manager, Section 2 Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No.: 50-374
Enclosure:
ASP Final Analysis (Sensitive - Not for Public Disclosure) cc w/o encl: See next page
C. Crane the document accordingly. We will inform you if the classification of the document changes as a result of our ongoing assessments.
Please contact me at 301-415-1364 if you have any questions regarding the enclosure.
Sincerely,
/RA/
Douglas V. Pickett, Senior Project Manager, Section 2 Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No.: 50-374
Enclosure:
ASP Final Analysis (Sensitive - Not for Public Disclosure) cc w/o encl: See next page DISTRIBUTION:
PUBLIC (Letter only) PDIII-2 R/F AMendiola PCoates DPickett OGC ACRS SReynolds, RIII SRosenberg AGrady, RES ADAMS Accession Number: ML041490106 (Package)
ADAMS Accession Number: ML041490103 (Letter)
ADAMS Accession Number: ML041210839 (Enclosure - Not for Public Disclosure)
OFFICE PM:LPDIII-2 LA:LPDIII-2 SC:LPDIII-2 NAME DPickett PCoates AMendiola DATE 06/01/04 06/01/04 06/01/04 OFFICIAL RECORD COPY
LaSalle County Station Units 1 and 2 cc:
Site Vice President - LaSalle County Station Exelon Generation Company, LLC 2601 North 21st Road Marseilles, IL 61341-9757 LaSalle County Station Plant Manager Exelon Generation Company, LLC 2601 North 21st Road Marseilles, IL 61341-9757 Regulatory Assurance Manager - LaSalle Exelon Generation Company, LLC 2601 North 21st Road Marseilles, IL 61341-9757 U.S. Nuclear Regulatory Commission LaSalle Resident Inspectors Office 2605 North 21st Road Marseilles, IL 61341-9756 Phillip P. Steptoe, Esquire Sidley and Austin One First National Plaza Chicago, IL 60603 Assistant Attorney General 100 W. Randolph St. Suite 12 Chicago, IL 60601 Chairman LaSalle County Board 707 Etna Road Ottawa, IL 61350 Attorney General 500 S. Second Street Springfield, IL 62701 Chairman Illinois Commerce Commission 527 E. Capitol Avenue, Leland Building Springfield, IL 62706 Robert Cushing, Chief, Public Utilities Division Illinois Attorney Generals Office 100 W. Randolph Street Chicago, IL 60601 Regional Administrator U.S. NRC, Region III 801 Warrenville Road Lisle, IL 60532-4351 Illinois Emergency Management Agency Division of Disaster Assistance &
Preparedness 110 East Adams Street Springfield, IL 62701-1109 Document Control Desk - Licensing Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Senior Vice President - Nuclear Services Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Vice President of Operations - Mid-West Boiling Water Reactors Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Vice President - Licensing and Regulatory Affairs Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555
LaSalle County Station Units 1 and 2 Director - Licensing and Regulatory Affairs Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Associate General Counsel Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Manager Licensing - Dresden, Quad Cities and Clinton Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555