ML033650385
| ML033650385 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 12/31/2003 |
| From: | Abney T Tennessee Valley Authority |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML033650385 (3) | |
Text
December 31, 2003 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Mail Stop: OWFN P1-35 Washington, D.C. 20555-0001 Gentlemen:
In the Matter of
)
Docket Nos. 50-259 Tennessee Valley Authority
)
50-260 50-296 BROWNS FERRY NUCLEAR PLANT (BFN) - UNITS 1, 2, AND 3 -
OPERATIONAL POWER RANGE MONITORS (OPRMs) - PLAN TO SUPPORT OPERABILITY This is in regard to the September 30, 2003, letter to NRC from K. S. Putnam, Chairman, Boiling Water Reactor Owners Group (BWROG), concerning plants utilizing the Option III stability solution (ML032751630). In that letter, the BWROG recommended that individual member utilities provide NRC with a status of the OPRM system and their plans to support OPRM operability. BFN Units 2 and 3 are currently in operation and have previously installed OPRM systems. Unit 1 is in an extended outage and hardware needed for the OPRM function has yet to be installed.
On Units 2 and 3, the OPRM system is in service with one out of four OPRM channels armed on Unit 3. The trip setpoint for the armed channel is based on the interim figure of merit (FOM) methodology. The remaining OPRM channels will be armed by mid-January 2004 on both operating units with FOM-derived setpoints. The OPRM system will not, however, be considered fully operable until completion of additional design changes (change in OPRM parameters) to resolve the condition discussed in the October 4, 2003, Part 21
U.S. Nuclear Regulatory Commission Page 2 December 31, 2003 notification (ML032870429) concerning the stability Option III Period Based Detection Algorithm. The defect in that Part 21 notification is associated with the values of period tolerance and conditioning filter cutoff frequency.
The plans are to implement the additional design changes on Unit 3 prior to the scheduled shutdown for the refueling outage in early Spring 2004. This will allow monitoring of OPRM system performance with the adjusted parameters during off-rated power conditions. Presuming successful performance, similar modifications will also be implemented on Unit 2 in Spring 2004, which will allow the OPRM systems on both operating units to be considered fully operable.
Since BFN is actively planning to request approval of Extended Power Uprate and Maximum Extended Load Line Limit Analysis Plus operation, longer term plans are to adopt the Detect and Suppress Solution - Confirmation Density (DSS-CD) approach. In the meanwhile, BFN will continue to use the current interim stability protection until the DSS-CD solution is approved and implemented.
There are no regulatory commitments associated with this submittal. If you have any questions on this subject, please contact me at (256)729-2636.
Original signed by:
T. E. Abney Manager of Licensing and Industry Affairs
U.S. Nuclear Regulatory Commission Page 3 December 31, 2003 BCM:BAB cc: A. S. Bhatnagar, PAB 1E-BFN M. J. Burzynski, BR 4X-C J. E. Maddox, LP 6A-C R. F. Marks, PAB 1C-BFN R. G. Jones, NAB 1A-BFN D. C. Olcsvary, LP 6A-C C. M. Root, PAB 1G-BFN J. R. Rupert, NAB 1A-BFN K. W. Singer, LP 6A-C M. D. Skaggs, POB 2C-BFN E. J. Vigluicci, ET 11A-K NSRB Support, LP 5M-C EDMS-K s:lic/submit/subs/OPRM Status.doc