ML20211C392
| ML20211C392 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 09/12/1997 |
| From: | James Anderson NORTHERN STATES POWER CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9709260174 | |
| Download: ML20211C392 (6) | |
Text
Northern states Power Company 1717 Wakonado Dr. E.
Welch. MN 55089 Telephone 612 3881121 September 12,1997 10 CFR Part 50 Section 50.90 U R Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 PRAIRIE ISLAND NUCLEAR GENERATING PLANT Docket Nos. 50 282 License Nos. DPR-42 50-306 DPR-60 License Amendment Request Dated May 7,1997 Supplement to the Amendment of Spent Fuel Pool Special Ventilation System Specifications This letter is submitted to supplement the subject license amendment request pursuant to discussions with the NRC Staff with respect to the methods by which Prairie Island handles its spent fuel pool covers within the spent fuel pool enclosure.
The document entitled, " Spent Fuel Pool Cover Handling", is included as and the figure showing the spent fuel pool bridge crane attachment to a cover section is included as attachment 2. The Prairie Island spent fuel pool cover comprises three cover sections. These cover sections may be used individually as work platforms over the spent fuel pools or new fuel pit. The cover sections may i
also be fastened together and used as a protective barrier for handling heavy loads as described in the subject license amendment request.
The discussion of the spent fuel pool protective covers in the original license amendment request, dated May 7,1997, generally made reference tc plant procedures governing the installation and use of the covers. Attachment 1 provides the substance of the implementing procedures for installation of the covers. NSP has evaluated the consequences of dropping one end of a cover section. As shown in Attachments 1 and 2, both ends of the cover sections are required to extend over the pool deck by a minimum of 8 inches and the cover is lifted a maximum of 6 inches above the pool deck. If a failure of the hoist or rigging on one end of a cover f
l section caused the cover section to drop, this physical geometry prevents the g
dropped end from falling into a spent fuel pool.
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DR ADOCK 030002 2'
- 9/12/97 Page 2 of 3 As described in Attachment 1, the cover is lifted so it clears the pool deck and then is verified to have the proper overlap of the spent fuel pool deck in the North-South direction. The cover sections are marked to facilitate this verification. If adjustment is required, one trolley is repositioned at a time. Once the cover section is in the proper North-South position, the North and South controls on both holsts are physically guarded to prevent inadvertent operation. The cover section movement is then confined to the East West directions by the spent fuel pool bridge crane rails.
In this manner a safe load path is defined consistent with NUREG-0612. The cover sections are not carried over any safe shutdown equipment when following this safe load path. The covers are handled over the suction and discharge nozzles for tha spent fuel pool cooling system. There is a suction and discharge nozzle for each nf the two pools spaced widely apart. However, these are not of concern since the procedures and geometry prevent the covers from falling into the pools.
Thus, NSP concluded that the cover sections can be handled in a safe manner which assures that the cover sectior.s do not fall into a spent fuel pool.
The original submittal made a commitment with respect to handling of loads over irradiated fuel. NSP proposes that the commitment be issued as a License Condition with this License Amendment es follows:
Prairie Island will assure that heavy loads do not present a potential for damaging irradiated fuel through use of: 1) a single-failure proof crane with rigging and procedures which implement Prairie Island commitments to NUREG-0612; or 2) spent fuel pool covers with their implementing plant procedures for installation and use.
A revised Safety Evaluation, Significant Hazards Determination and Environmental Assessment have not been submitted with the additional information provided by this letter since these evaluations, as originally presented in the May 7,1997 submittal, continue to bound the proposed license amendment as modified by this supplement.
If you have any questions related to this information in support of the subject license amendment request, please contact Dale Vincent at 612-388-1121.
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Roger O. Anderson
- Director, Nuclear Enargy Engineering Attachments and copies shown on Daoe 3
- 9/12/97 Page 3 of 3 Attachments:
Affidavit 1.
Spent Fuel Pool Cover Handling 2.
Spent Fuel Pool Cover Section Attached to Spent Fuel Pool Bridge Crane c:
Regional Administrator-Ill, NRC NRR Project Manager, NRC Senior Resident inspector, NRC State of Minnesota Attn: Kris Sanda J E Silberg
UNITED STATES NUCLEAR REGULATORY COMMISSION NORTHERN STATES POWER COMPANY PRAIRIE ISLAND NUCLEAR GENERATING PLANT DOCKET Nos. 50 282 50 306 REQUEST FOR AMENDMENT TO OPERATING LICENSES DPR-42 & DPR 60 LICENSE AMENDMENT REQUEST DATED May 7,1997 Amendment of Spent Fuct Pool Special Ventilation System Specifications Northern States Power Company, a Minnesota corporation, by this letter dated September 12,1997 provides supplementalinformation in support of the subject license amendment request dated May 7,1997. Attachment 1 provides details of Prairie Island's methodology for handling spent fuel pool cover sections. Attachment 2 is a figure showing a cover section attached to the spent fuel pool bridge crane.
This letter and its attachments contain no restricted or ciher defense information.
NORTHERN STATES POWER COMPANY By rd R6gern Anderson
- Director, Nuclear Energy Engineering On this 11 day of btOffmlMV before me a notary public in and for said County,' personally appeared, Roger O. Anderson, Director, Nuclear Energy Engineering, and being first duly sworn acknowledged that he is authorized to execute this document on behalf of Northern States Power Company, that he knows the contents thereof, and that to the best of his knowledge, information, and belief the statements made in it are true and that it is not inter-posed for delay.
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Attachment i Spent Fuel Pool Cover Handling 1.
Position the West Hoist and New Fuel Hoist on the west rail of the spent fuel pool bridge crane.
2-Line the spent fuel pool bridge crane with the cover section to be lifted.
3.
Position a hoist over each of the cover lifting rings and rig each hoist to the corresponding cover lifting ring.
4.
Move both holsts slightly to the south (approximately 2 inches) so the cover will move toward the south when lifted.
5.
Lift the cover section until it just clears the floor. Adjust to achieve minimum overlap.
6.
Verify the cover position relative to the edges of the spent fuel pool. The south end of the cover is required to extend at least 8 inches over the 755 El. floor and the north end is required to extend at least 8 inches over the 755 El. floor.
7.
Put guards over the NORTH and SOUTH trolley control buttons on both hoist pendants. This will prevent inadvertent movement of the trolleys in the north or south directions.
8.
Lift cover to working height and move to new location in the spent fuel pool enclosure.
9.
Lower cover until it just touches the 755 E. floor, remove the trolley button covers, and position cover section for final position.
10.
Lower the cover section into position.
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LIFTING RINGSx l
A GANTRY LEG
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1 N 2'-9 /( /
COVER SECTION 2'-qf-h 1'
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(1 OF 3)
I 6" MAX."
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OECK 8" MIN.
8' MIN.
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9 SPENT FUEL POOL COVER SECTION M
ATTACHEO TO SPENT FUEL POOL BRIDGE CRANE y
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