ML051880050
| ML051880050 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 06/30/2005 |
| From: | Vanderheyden G Constellation Energy Group |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML051880050 (2) | |
Text
George Vanderheyden 1650 Calvert Cliffs Parkway Vice President Lusby, Maryland 20657 Calvert Cliffs Nuclear Power Plant 410.495.4455 Constellation Generation Group, LLC 410.495.3500 Fax Constellation Energy June 30, 2005 U. S. Nuclear Regulatory Commission Washington, DC 20555 ATTENTION:
Document Control Desk
SUBJECT:
Calvert Cliffs Nuclear Power Plant Unit Nos. I & 2; Docket Nos. 50-317 & 50-318 Appendix K Measurement Uncertainty Recapture -
Power Uprate Request, Supplemental Information
REFERENCE:
(a)
Letter from G. Vanderheyden (CCNPP) to Document Control Desk (NRC), dated January 31, 2005, same subject In our measurement uncertainty recapture (MUR) power uprate license amendment request (Reference a),
we described a phenomenon where the CROSSFLOW system venturi flow correction factor changes as a function of reactor power. To address this concern, we committed to install X-BEAM ultrasonic flow meters on Unit I and obtain data to determine if the power dependency could be eliminated.
We committed to provide the results of this testing to the Nuclear Regulatory Commission staff by July 1, 2005. The results are provided below.
As noted in the referenced submittal, X-BEAM ultrasonic flow meters were installed on Unit 1, downstream of the flow straightener in each feedwater loop. Unit I subsequently reduced power on June 3, 2005 to acquire feedwater flow data using the X-BEAM ultrasonic flow meters. Plant power was reduced for eight hours to acquire statistically meaningful data. Review of that data indicates that the X-BEAM ultrasonic flow meters also show a power dependency in the venturi correction factor similar in nature to the dependency observed in the original CROSSFLOW system. It has been determined that this power dependency is due to the flow straightener located upstream of the flow meters. However, based on the data acquired, we have determined that the change in feedwater venturi flow correction factor due to the power dependency is predictable and linear in nature.
To address the power dependency, an algorithm has been built into the CROSSFLOW plant computer interface software. This software feature will be tested prior to implementing the MUR power uprate and will resolve the power dependency issue that we have observed on Units I and 2.
The information contained in this letter does not affect the No Significant Hazards Determination or the Environmental Impact Review provided in Reference (a).
/ CD
Document Control Desk June 30, 2005 Page 2 Should you have questions regarding this matter, please contact Mr. L. S. Larragoite at (410) 4954922.
Very STATE OF MARYLAND COUNTY OF CALVERT
- TO WIT:
I, George Vanderheyden, being duly sworn, state that I am Vice President - Calvert Cliffs Nuclear Power Plant, Inc. (CCNPP), and that I am duly authorized to execute and file this License Amendment Request on behalf of CCNPP. To the best of my knowledge and belief, the statements contained in this document are true and correct. To the extent that these statements are not based on my personal knowledge, they are based upon information provided by other CCNPP employees and/or consultants. Such information has been reviewed in accordance with company practice and I believe it to be reliable.
Subscribed and sworn before me a NotaUlic in and for the State of Maryland and County of
- 71at
, this e
day of I 2005.
WITNESS -my Hand and Notarial Seal:
My Commission Expires:
Notary Pubi Date' GV/PSF/bjd cc:
P. D. Milano, NRC S. J. Collins, NRC Resident Inspector, NRC R. 1. McLean, DNR