ML20217D512
| ML20217D512 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 04/20/1998 |
| From: | Abney T TENNESSEE VALLEY AUTHORITY |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9804240365 | |
| Download: ML20217D512 (3) | |
Text
e RA Tennessee Vaney Authority. Post Omce Box 2000, Docatur, Alabarna 35fM2000 April 20, 1998 TVA BFN TS-362 U.S. Nuclear Regulatory Commission ATTN:
Document Control Desk i
Washington, D.C. 20555 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 TECHNICAL SPECIFICATIONS (TS) CHANGE 362 - IMPROVED TECHNICAL SPECIFICATIONS (ITS) - SUPPLEMENTAL INFORMATION -
i CHANGES TO INSTRUMENTATION SURVEILLANCE TEST INTERVALS (STIs) AND ALLOWED OUT-OF-SERVICE TIMES (AOTs)
This letter is in response to a verbal request from NRC staff concerning the December 11, 1997, TVA submittal which provided the basis for changes made in the ITS from Current Technical Specifications (CTS) related to extensions of instrumentation system STIs.
Specifically, NRC requested confirmation that increases in instrument drift due to extended STIs is properly accounted for in the TVA instrument setpoint methodology.
In the NRC Safety Evaluation Reports (SERs) for the Boiling Water Reactor Owners Group (BWROG) Topical Reports on extending STIs and AOTs for instrumentation, a requirement ij; was imposed which stated that plants must confirm that any
\\l l increase in instrument drift due to the extended STIs is l'
properly accounted for in the setpoint methodology.
(
Reference:
letter from C.E. Rossi (NRC) to R.F.
Janecek 9804240365 980420 DR ADOCK 05000259 p
PDR j
m Pmeno or secyana ave
l U.S. Nuclear Regulatory Commission Page 2 April 20, 1998 (BWROG) dated April 27, 1988).
As stated in the December 11, 1997 submittal, TVA's setpoint methodology accounts for drift inaccuracies associated with durations between calibrations.
In particular, TVA instrumentation setpoint calculations are performed in accordance with ISA STD ISA-S67.04-1982 "Setpoints for Nuclear Safety Related Instrumentation used in Nuclear Power Plants".
The drift information is either based on vendor published drift data or on plant specific drift data for the equipment / component.
)
The calibration intervals established by the setpoint methodology were reviewed against the STIs propcsed in the ITS submittal (TS-362) to assure that the required calibration intervals are not exceeded.
In some cases, the proposed calibration surveillances may be performed more frequently, but will not exceed the required calibration j
interval.
This approach satisfies the NRC requirement included in their SERs on the Topical Reports and the letter from C.E. Rossi to R.F.
Janecek, dated April 27, 1988.
)
i Therefore, TVA has concluded that the BWROG generic analyses are applicable to BFN and the STI extensions as proposed and justified in TS-362 are acceptable.
This satisfies the respective SER requirements.for the determination of plant specific acceptability for use of the generic analyses.
If you have further questions on this subject, please contact me at (256) 729-2636.
Spacerely,.
-l s
'. E.
Manager of ensin and Industry ffairs cc:
See page 3
i a
U.S. Nuclear Regulatory Commission Page 3 April 20, 1998 cc:
Chairman Limestone County Commission 310 West Washington Street Athens, Alabama 35611 Mr. A. W. De Agazio, Project Manager U.S. Nuclear Regulatory Commission One White Flint, North 11555 Rockville Pike Rockville, Maryland 20852 Mr. Harold O.
Christensen, Branch Chief U.S. Nuclear Regulatory Commission Region II Atlanta Federal Center 601 Forsyth St.,
Suite 23T85 Atlanta, Georgia 30303 NRC Resident Inspector Browns Ferry' Nuclear Plant 10833 Shaw Road Athens, Alabama 35611 1
Dr. Donald E. Williamson State Health Officer Alabama State Department of Public Health 434 Monroe Street Montgomery, Alabama 36130-3017
)
i l
l
\\
l 1