ML20082P896
| ML20082P896 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 08/21/1991 |
| From: | Dipiazza R WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP. |
| To: | Hood D Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML19302F125 | List: |
| References | |
| CAW-91-140, NUDOCS 9109110137 | |
| Download: ML20082P896 (4) | |
Text
,4
- 1
/
\\
(v) 4 Westinghouse Energy Systems y3))pmmwmaocan E!ectric Corporation Mr. Darl S. Hood, Project Manager August 21, 1991 P.roject Directorate 11-3 Division of Reactor Projects 1/11 Office of Nuclear Reactors Regulation Nuclear Regulatory Commission Washington, DC 20555 RE: CAW-91-140
Dear Mr. Hood:
I have reviewed your letter requesting public disclosure of proprietary information contained within WCAP-12788, Revision 1, entitled "RTD Bypass i
Elimination Licensing Report for Vogtle Electric Generating Plant".
Specifically, the proprietary nature of the information Presented in Tables 2.1-1 and 3.1-4 was reviewed by the Westinghause technical disciplines which generate and utilize the information.
The subject information has been classified as proprietary in accordance with designations (a) and (c) from Affidavit CAW-91-140. These designations refer to:
(a) distinguishing aspects.of a process (or component, structure, tool, method, etc.) where prevention of its use by any of Westinghouses's competitors without license from Westinghouse constitutes a competitive economic advantage over other companies, and (c) use by a competitor which would reduce his expenditure of resources or improve his competitive position in the design, manufacture, shipment, installation, assurance of quality, or licensing a similar product.
We have concluded that Table 2.1-1 can be released to the public without any significant harm to our competitive advantage in safety analysis methodology.
However, the information presented in Table 3.1-4 reveals distinguishing aspects of Westinghouse supplied equipment that is specifically modeled in the methodology presented in the report for setpoint determination.
Access to this information_by our competitors would reduce their effort required to generate similar'information, which we have defined at considerable expense of time and etfort.
For example, Table 3.1-4 contains instrument uncertainty information (sensor / transmitter and process rack errors including the conversion to the working unit, % flow) derived from the following:
m 9109110137 910904 PDR ADOCK 05000424 p
i i
f Mr. Darl S. Hood Page 2 t
- 1) Equipment specifications required and verified by test at considerable Westinghouse expense as part of the various i
equipment qualification programs.
- 2) Process measurement accuracier, for non instrument related effects t
.which were determined by Westinghouse by calculation, measurement or assumption and subsequently reviewed and approved by the NpC.
- 3) Procedural requirements specified by Westinghouse to ensure operation consistent with protection function operability l
requirements.
l
- 4) The results of parameter sensitivity calculations using a Westinghouse determined approach.
Westinghouse first developed this approach to instrument uncertainty
)
calculation (using items 1 through 4 above) in 1977 and was first presented to the NRC in 1978. The approach has subsequently been refined with improvements provided in various plant specific submittals, e.g.,
Protection System Setpoint Studies, Improved Thermal Design Procedure i
rmorts and RTD Bypass Elimination reports with identical. proprietary
'oi eketing and coding noted in each.. The overall combination methodology i
was first published in a non-proprietary form in an IEEE Nuclear Science Symposium paper in 1985.
Thus, release of the information in Table 3.1-4, or information of a similar nature, would allow a competitor to perform uncertainty calculations on a plant with Westinghouse supplied equipment using a Westinghouse developed methodology and Westinghouse developed uncertainties without incurring the same or similar development j!
costs.
This would )rovide a considerable cost savings to a competitor in.
an area where, at t11s time, only the Westinghouse methodology has explicit NRC approval (see NUREG 0717 Supplement No. 4, August 1982).
)
An a'dditional request for release of proprietary information on Table 3.1-8 from WCAP-13788, Revision 1 was discussed in a conference call with the NRC Staff on August 21, 1991.
It was determined that the value for j
"N LOOP RCS FLOW UNCERTAINTY (WITH BIAS VALUES)" may be released to the-public.
In conclusion, due to the distinguishing _ aspects of Westinghouse equipment which it may reveal, in addition to the reduction of a f
competitorfs resource expenditure to generate similar information, we i
maintain our request for withholding public disclosure of Table 3.1-4 in l
WCAP-12788, Revision 1.
The relative sensitivity of Table 2.1-1 and the value for N loop RCS flow uncertainty (with bias values) on Table 3.1-8
'has been determined to be not as great and we therefore concur with releasing this information to the public.
j q
. P. DiPiazza,~Manag Nuclear Safety Licensing Westinghouse Electric Corporation l
l
TABLE 2.1-1 RESPONSE TIME PARAMETERS FOR RCS TEMPERATURE HEASUREHENT
~ RTD Fast Response Bvoass System Thermowell RTO System RTD Bypass Piping and Thermal Lag (sec) 2.0 NA RTD Response Time (sec) 2.0 4.0 Electronics Delay (sec) 2.0 2.0 Total Response Time (sec) 6.0 sec 6.0 sec r
l l
o e
9 7
8 11
. =
4
~
TABLE 3.1-B 4
COLD LEG ELB0H TAP FLOW UNCERTAINTY INSTRUMENT UNCEnTAINTIES
+8,C
% DP SPAN
% FLOW PHA PEA SCA SPE STE SD RCA H&TE -
RTE RD ID A/D RDOT -
FLOH CALORIM. BIAS FLON CALORIMEIRIC INSTRUMENT SPAN
+a.C SINGLE LOOP ELB0H TAP FLOH UNC =
% FLOW N LOOP ELB0H TAP FLOH UNC N LOOP RCS'FLOH UNCERTAINTY (HITH BIAS VALUES) 1.9 1
l l
24