ML042390059
| ML042390059 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse, Oconee, Arkansas Nuclear, Crystal River, Robinson, PROJ0693, Crane  |
| Issue date: | 08/20/2004 |
| From: | Mallay J B & W Owners Group |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NRC-04-048, OG:04:1852 | |
| Download: ML042390059 (2) | |
Text
Duke Energy Company Oconee 1, 2,3 AmerGen Energy Company, LLC TMI-1 Entergy Operations, Inc.
ANO-1 The B&W FirstEnergy Nuclear Operating Company D-B Florida Power Corporation Crystal River 3 Owners Groupl Framatome ANP Working Together to Economically Provide Reliable and Safe Electrical Power August 20, 2004 NRC:04:048 OG:04:1852 Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 B&WOG Response on Residual Heat Removal (RHR) Availability in Mode 6 Ref.: 1. Meeting with the Westinghouse Owners Group (WOG) and the Babcock and Wilcox Owners Group (B&WOG) Regarding Residual Heat Removal (RHR) Availability in Mode 6, June 24, 2004.
At a June 24 meeting with the B&WOG and the WOG (Reference 1), the NRC requested that the B&WOG describe the plant tech spec and operating practice for each of the B&W units concerning the availability of residual heat removal while in Mode 6.
The technical specifications for each of the B&WOG units have similar requirements for having one or two RHR trains operable or operating. One RHR train is required to be operable and operating if the water level is 23 feet or more above the top of the reactor vessel flange. Two RHR trains are required to be operable and one operating if the water elevation is less than 23 feet above the top of the reactor vessel flange.
Five of the B&W units - TMI-1, Oconee-1, 2, and 3, and Arkansas - normally remove the plenum prior to establishing the water level to the point where only one RHR train is required to be operable and operating.
Two RHR trains are required to be operable with one operating during 'dry removal' of the plenum.
The remaining two units, Crystal River and Davis Besse, typically remove the plenum under water with the water level above 23 feet. One RHR train must be operable and operating for this sequence.
NUREG-5820 was reviewed to determine its applicability to the B&WOG units. NUREG-5820 contains analyses of several configurations and loss of RHR scenarios for the H.B. Robinson and Oconee nuclear plants. The conclusions discussed in the NUREG are based on a total flow area of 1.0 sq. ft. through the upper support plate. Since the concern is with flow areas substantially less than that available in B&WOG units, the B&WOG member plants are not affected. If the water level is at or above 23 feet above the reactor vessel flange and RHR is lost, the entire volume of water above the plenum is available for cooling in the B&W design. This situation pertains whether the plenum is installed or not since there is more than 20 square feet of flow area available between the pool and the core even with the plenum installed.
Framatome ANP B&W Owners Group 3315 Old Forest Road Lynchburg, VA 24501 D~L s Phone: 434-832-2981 Fax: 434-832-2475
Document Control Desk NRC:04:048 August 20, 2004 OG:04:1852 Page 2 The current tech specs for all B&WOG units should be retained because there is adequate assurance that cooling water is available under all refueling conditions.
Very truly yours, am lay, Dreco Regulatory Affairs cc:
D. G. Holland Project 693