ML18152A362
| ML18152A362 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 06/26/1997 |
| From: | Ohanlon J VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 97-364, IEB-96-002, IEB-96-2, NUDOCS 9707090320 | |
| Download: ML18152A362 (6) | |
Text
VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 June 26, 1997 United States Nuclear Regulatory Commission Attention: Document Control Desk Washington, D. C. 20555-0001 Gentlemen:
VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION UNITS 1 AND 2 Serial No.
NL&OS/GDM Docket No.
License No.97-364 R1 50-280
. 50-281 DPR-32 DPR-37 NRC BULLETIN 96-02, MOVEMENT OF HEAVY LOADS OVER SPENT FUEL, OVER FUEL IN THE REACTOR CORE, OR OVER SAFETY-RELATED EQUIPMENT RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION In our submittal dated February 10, 1997 (Serial No.96-630), Virginia Electric and Power Company responded to a NRG request for additional information dated December 6, 1996 related to NRG Bulletin 96-02, "Movement of Heavy Loads Over Spent Fuel, Over Fuel in the Reactor Core, or Over Safety-Related Equipment." The NRG request discussed a postulated accident scenario involving the drop of a spent fuel storage or transportation cask during cask movement prior to installation and/or securing of the cask structural lid. Our response provided the basis for why we do not consider the postulated accident to be credible for Surry Power Station.
It also identified the additional procedural controls that were established to further ensure the safe handling of our spent fuel casks.
Subsequent to our submittal, a telephone call was held between the NRG staff and Virginia Electric and Power Company personnel. The purpose of the call was to further discuss the procedure for lifting a loaded spent fuel cask from the bottom of the spent fuel pool to the point where the cask is partially out of the water and the lid bolts (or studs and nuts) are installed. Of particular interest to the NRC were the controls and J
design features that are in place to preclude a cask tipover should the cask fall during the lift from the bottom of the spent fuel pool to the position partially out of the water and prior to securing the structural lid. These items were discussed during the call and are documented herein pursuant to the NRC's request.
The attached sketch (Attachment 1) shows the cask loading area which is located in the.
1 [
1 east end of the spent fuel pool. There are two cask impact pads installed in the bottom A"(J l of the cask loading area with the lower pad being used for cask loading activities. As._~
shown on the sketch, after spent fuel is loaded into a cask and the lid is set, the cask is 9707090320 970626 PDR ADOCK 05000280 G
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raised vertically until approximately two to four feet of the cask is above the surface of the spent fuel pool.
At this point, the cask, which is typically 16 feet in height, is suspended in the spent fuel pool from the fuel building crane approximately 26 to 28 feet above the cask impact pad. All of the lid bolts (or studs and nuts) are installed by hand while the cask is suspended in this position at the pool surface. This activity requires approximately thirty minutes to complete.
The attached photograph (Attachment 2) shows a cask in position to have the lid bolts installed. The cask is then dewatered in this position and moved to the cask operations bay where operations such as vacuum drying and leak testing are conducted.
There are no obstructions in the cask loading area of the spent fuel pool that would serve to cause rotation of a cask during a drop from this suspended position.
Furthermore, by procedure, the lifting yoke and cask trunnions are oriented in a north-south direction which would direct the cask toward the pool wall if one trunnion or yoke arm were to fail. In this case, the top or bottom of the cask would hit the wall before the cask center of gravity rotates over the corner. Therefore, we do not consider a cask tipover to be credible during this lifting evolution.
No new commitments are intended as a result of this letter. Should you have any questions or require additional information, please contact us.
Very truly yours, James P. O'Hanlon Senior Vice President - Nuclear Attachments cc:
U.S. Nuclear Regulatory Commission Region II Atlanta Federal Center 61 Forsyth St., SW, Suite 23T85 Atlanta, Georgia 30303 Mr. R. A. Musser NRC Senior Resident Inspector Surry Power Station
Spent Fuel Pool Cask Handling Sketch
21' -4*
--EL q* -2' i--------,
CASK IMPACT PAO
- a--,N
- SPENT FI.E.
CASK CASK IMPACT PAO EL 47'-4*
EL 45*-4*
r,.J EL 33' -0*
El 6'-8 1 VIEW LOOKING WEST SURRY POWER STATION FUEL BUILDING SIDE VIEW IZl51111HF'Sl,.I
Spent Fuel Pool Cask Handling Photograph j