ML19269C887
| ML19269C887 | |
| Person / Time | |
|---|---|
| Site: | Zion File:ZionSolutions icon.png |
| Issue date: | 02/13/1979 |
| From: | Reed C COMMONWEALTH EDISON CO. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 7902200037 | |
| Download: ML19269C887 (4) | |
Text
Commonwealth Edison One First National Plata. Chicago, Illinois Address Reply to: Post Office Box 767 Y
Chicago, Illinois 60690 February 13, 1979 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555
Subject:
Zion Station Units 1 and 2 Additional Information for Proposed Change to FN Rod Bow Penalty Curve and EFPH ClN Collapse Limits NRC Docket Nos. 50-295 and 50-304 References (a) :
October 27, 1978 letter frcan C. Reed to Director of Nuclear Reactor Regulation requesting license amendment to change F[HrodbowpenaltycurveandEFPHclad collapse limits (b):
December 19, 1978 letter from A. Schwencer to Cordell Reed (c):
November 21, 1978 letter from Cordell Reed to H. R. Denton providing a description of' Zion Extended Burnup Program
Dear Mr. Denton:
Per discussions with the NRC Staff concerning Commonwealth Edison Company's license amendment request of Reference (a), the Staff requested additional information concerning the potential environmental impact on both the uranium fuel cycle and the transportation of fuel and waste from Zion Station that could result from the proposed irradiation of four assemblics for one and possibly two additional cycles of ooeration.
Commonwealth Edison has examined the potential environmental impact of this program with the conclusion that no additional impact on the environment will accrue due to this program.
In fact, the environmental impact is less because less power will be generated during the two proposed cycles, i.e. the proposed cycles will be shorter due to the fact that in the program four, thrice burned assemblies will replace eight (four for each proposed cycle), once burned assemblies.
790220003 7
Commonwealth Edison NRC Docket Nos. 50-295/304
)
Mr. Harold R.
Denton: February 13, 1979 In addition, per Reference (b) the NRC Staff has limited the scope of its review of Commonwealth Edison's proposed amendment of Reference (a) to an experimental program, as described in Reference (c), for a maximum of four fuel assemblies and for a maximum of two cycles.
Consequently, the technical specification changes of Reference (a) require modification to reficct the limited scope.
The attachment to this letter contains these technical specification modifications.
Please address any additional questions that you might have to this office.
One (1) signed original and thirty-nine (39) copies of this letter are provided for your use.
Very truly yours, 9"
Cordell Reed Assistant Vice-President attachment
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The F Penalty is applicable for allfhelassembliesupto38400 MWD /MTU,
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10 20 30 4C 50 Region Average Burnup (1000 '?mer!'U) 61
In accordance with the approved Westinghouse model DNB Parameters:
The limits on the DNB re-as presented in WCAP 8381, no collapses are expected lated paramters assure that each of the throughout the fuel cycle of operation.
The pre-parameters is maintained within the normal dicted minimum times for clad flattening are:
steady state envelope of operation assumed in the transient and accident analyses.
Fuel Region EFPH The limits are consistent with the initial FSAR assumptions and have been analytically 1
19,500 demonstrated adequate to maintain a minimum 2
> 30,000 DNBR of 1.30 throughout each analyzed j
3*
> 30,000 transient.
for Zion Unit 1.
The predicted minimum times to The 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> periodic surveillance of these collapse for Unit 2 are:
parameters thru instrument readout is sufficient to ensure that the parameters Fuel Region EPPH are restored within their limits following load changes and other expected transient 1
27,000 operation.
The 18 month periodic measurement of 2
> 30,000 of the RCS total flow rate is adequate to I
3*
> 30,000 detect flow degradation and ensure correlation of the flow indication channels with measured A design criterium requires that proposed reload flow such that the indicated percent flow fuel region exposure levels expected at the time will provide sufficient verification of flow of discharge not exceed the predicted minimum rate on a 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> basis.
collapse time.
Operation in the exposure range in which clad collapse is postulated is not per-A quadrant to average power tilt will be mitted under these technical specifications.
indicated by the excore detectors.
The excore current tilt is indicated by the The predicted minimum time to collapse for all arrangement of the current recorders on the reload fuel regions is greater than 30,000 effec-control board.
Four 2 -pen recorders are prc-tive full power hours.
vided, the pens are grouped so that, in the absence of a tilt, the two
- Except that the four (4) Region 3 assmeblies to be used in the Extended Burnup Program have a predicted minimum time to collapse greater than 41000 EFPH.