ML031410178
| ML031410178 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 05/23/2003 |
| From: | Rossbach L NRC/NRR/DLPM/LPD3 |
| To: | Skolds J Exelon Generation Co, Exelon Nuclear |
| Rossbach L , NRR/DLPM, 415-2863 | |
| References | |
| TAC MB7840, TAC MB7841 | |
| Download: ML031410178 (4) | |
Text
May 23, 2003 Mr. John L. Skolds, President Exelon Nuclear Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3 - REQUEST FOR ADDITIONAL INFORMATION REGARDING HEAVY LOADS HANDLING AMENDMENT REQUEST (TAC NOS. MB7840 AND MB7841)
Dear Mr. Skolds:
By letter dated February 26, 2003, Exelon Generation Company submitted an amendment request concerning heavy loads handling at Dresden Nuclear Power Station, Units 2 and 3.
The staff has identified additional information that is needed in order to complete their review of this relief request in the area of mechanical and civil engineering. These questions were discussed with members of your staff on May 15, 2003. Your staff agreed to respond to this request for additional information (RAI) within three weeks of the date of this letter.
Please contact me at (301) 415-2863 if your staff has any questions about this RAI.
Sincerely,
/RA/
Lawrence W. Rossbach, Project Manager, Section 2 Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket Nos. 50-237 and 50-249
Enclosure:
Request for Additional Information cc w/encl: See next page
May 23, 2003 Mr. John L. Skolds, President Exelon Nuclear Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3 - REQUEST FOR ADDITIONAL INFORMATION REGARDING HEAVY LOADS HANDLING AMENDMENT REQUEST (TAC NOS. MB7840 AND MB7841)
Dear Mr. Skolds:
By letter dated February 26, 2003, Exelon Generation Company submitted an amendment request concerning heavy loads handling at Dresden Nuclear Power Station, Units 2 and 3.
The staff has identified additional information that is needed in order to complete their review of this relief request in the area of mechanical and civil engineering. These questions were discussed with members of your staff on May 15, 2003. Your staff agreed to respond to this request for additional information (RAI) within three weeks of the date of this letter.
Please contact me at (301) 415-2863 if your staff has any questions about this RAI.
Sincerely,
/RA/
Lawrence W. Rossbach, Project Manager, Section 2 Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket Nos. 50-237 and 50-249
Enclosure:
Request for Additional Information cc w/encl: See next page Distribution:
PUBLIC PDIII/2 r/f A. Mendiola P. Coates L. Rossbach OGC ACRS J. Rajan M. Ring, RIII ADAMS Accession Number: ML031410178 OFFICE PM:PD3-2 LA:PD3-2 SC:PD3-2 NAME LRossbach THarris for PCoates AMendiola DATE 5/23/03 5/23/03 5/23/03 OFFICIAL RECORD COPY
Dresden Nuclear Power Units 2 and 3 cc:
Site Vice President - Dresden Nuclear Power Station Exelon Generation Company, LLC 6500 N. Dresden Road Morris, IL 60450-9765 Dresden Nuclear Power Station Plant Manager Exelon Generation Company, LLC 6500 N. Dresden Road Morris, IL 60450-9765 Regulatory Assurance Manager - Dresden Exelon Generation Company, LLC 6500 N. Dresden Road Morris, IL 60450-9765 U.S. Nuclear Regulatory Commission Dresden Resident Inspectors Office 6500 N. Dresden Road Morris, IL 60450-9766 Chairman Grundy County Board Administration Building 1320 Union Street Morris, IL 60450 Regional Administrator U.S. NRC, Region III 801 Warrenville Road Lisle, IL 60532-4351 Illinois Department of Nuclear Safety Office of Nuclear Facility Safety 1035 Outer Park Drive Springfield, IL 62704 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 Mid-West Regional Operating Group Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Senior Vice President Mid-West Regional Operating Group 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 Director - Licensing Mid-West Regional Operating Group Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Senior Counsel, Nuclear Mid-West Regional Operating Group Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Manager Licensing - Dresden and Quad Cities Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555
Dresden Nuclear Power Station, Units 2 and 3 Request for Additional Information on Heavy Load Handling Amendment Request 1.
The load drop of a shield plug during lifting of the plug from the cavity in Unit 3 and laying it down on top of Unit 2 shield plugs is analyzed as Scenario 1 of the load drop analysis (Attachment 3 of the amendment request). The calculations for determining the bearing capacity of the top shield plug on page 29 of 95, utilize a strength reduction factor of 0.7 for the bearing strength of concrete and a 2/3 factor to account for the spaces between the bearing bars. Provide the basis and applicable reference material for the use of this strength reduction factor and 2/3 factor.
2.
Provide justification for not taking the concrete reinforcement into consideration in the determination of the weight of the slab, beams and column in the calculations related to the Full drop of a shield plug on single column which is Scenario 2 of the load drop analysis.
3.
The full drop of a shield plug on a system of two adjacent slabs with a beam in between the slabs, is analyzed as Scenario 3 of the load drop analysis. In this calculation the combined beam and slab moment resistance factor, as discussed on page 68 of 95, is obtained on the basis of an equation provided on this page. Provide an explanation of how this equation reduces the beam moment resistance that accounts for the area of the two adjacent slabs as indicated.
4.
The full drop of a shield plug on wall at column 44 is analyzed as Scenario 5 of the load drop analysis. Provide a definition of the factor Kwall = 0.8" used on page 89 of 95 of this calculation and explain how it is obtained.
5.
Provide a drawing or illustration of the maximum height that a top shield plug can drop and explain why this height is the maximum possible drop height.
6.
Are the 1997 Code Requirements for Nuclear Safety Related Concrete Structures (ACI 349-97) and the 1999 Building Code Requirements for Structural Concrete (ACI 318-99) referenced in calculation DRE02-0064 attached to your submittal the current versions of these codes? If there are later versions, why werent they used and how would they affect the calculation?