ML20204A754
| ML20204A754 | |
| Person / Time | |
|---|---|
| Site: | Duane Arnold  |
| Issue date: | 01/22/1999 |
| From: | IES UTILITIES INC., (FORMERLY IOWA ELECTRIC LIGHT |
| To: | |
| Shared Package | |
| ML20136C773 | List: |
| References | |
| NUDOCS 9901280252 | |
| Download: ML20204A754 (5) | |
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TSCR 007 to NG-99-0049 Pageioft PROPOSED CHANGE TSCR-007 TO THE DUANE ARNOLD ENERGY CENTER TECIINICAL SPECIFICATIONS The holders oflicense DPR-49 for the Duane Arnold Energy Center propose to amend the Technical Specifications by deleting the referenced page and replacing it with the enclosed new page.
SUMMARY
OF CHANGES:
i Eage Descrintion of Chances 4.0-2 Revises 4.3.1.1.a. to update the spent fuel storage racks criticality requirements (k-infinity and U-235 enrichment limits) to allow for storage of nuclear fuel assemblies with new designs, including -
GE-12 with a 10x10 pin array.
Revises 4.3.1.1.c. to correct misspelling. PARR should be par.
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99012P0252 990122 PDR ADOCK 05000331 P-PDR
I Design Features t
t, 4.0 4.0 DESIGN FEATURES (continued) 4.3 Fuel Storage 4.3.1 Criticality 4.3.1.1 The spent fuel storage racks are designed and shall be maintained with:
gee.gg.eg e
- a. [ Fuel semblies ha ng a tr.axi
-1nfinity 1.31 in e normal r tor core to iguration cold dttions an n average 35 enrichme of 4.6 1
l gde.k ight perc b.
wfilch includes an allowance for uncertainties described in Section 9.1 of the UFSAR: and c.
A nominal 6.060 i for HOLTEC designed and 6.625 inches fo esigned center to center distance between assemblies placed in the storage racks.
gg 4.3.1.2 The new fuel storage racks are designed and shall be maintained with:
Fuel assemblies having a maximus k-infinity of 1.31 a.
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in the normal reactor core configuration at cold conditions:
i b.
k wfiIch includes an allowance for uncertainties ass described in Section 9.1 of the UFSAR:
k,,, s 0.90 if dry. which includes an allowance for c.
l uncertainties as described in Section 9.1 of the UFSAR: and i
d.
A nominal 6.625 inch center to center distance between fuel assemblies placed in storage racks.
(continued) 1 DAEC 4.0-2 f.xci..~.it 223 t
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INSERT FOR PROPOSED CIIANGE TO PAGE 4.0-2 l
Fuel assemblies having the following limits for maximum k-infinity in the normal reactor core configuration at cold conditions and maximum lattice-average U-235 enrichment weight percent:
k-m wt %
i) 7x7 and 8x8 pin arrays s 1.31 s 4.6 (11oltec and par racks) ii) 9x9 and 10x10 pin arrays s 1.29 6 4.95 (Iloltee racks) iii) 9x9 and 10x10 pin arrays s 1.39 5 4.95 (par racks) i i
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1 TSCR-007 to NG-99-0049 Page1ofI SAFETY ASSESSMENT By letter dated January 22,1999, IES Utilities Inc. submitted a request for revision of the Technical Specifications for the Duane Arnold Energy Center (DAEC). The proposed amendment updates the criticality requirements (k-infinity and U-235 enrichment limits) for storage of fuel assemblies in the spent fuel racks. This change will allow for storage of nuclear fuel assemblies with new designs, including GE-12 with a 10x10 pin array.
Evaluatiom The UFSAR Safety Design Bases for Spent Fuel Storage is as follows:
UFSAR 9.1.2.1.3 Safety Design Bases:
The fuel array in the fully loaded spent fuel racks will be substantially suberitical and prevent fuel barrier damage caused by overheating. For any operating or accident condition which is a design basis for DAEC, the suberitical multiplication factor (K-eff) is maintained below 0.95. This includes the worst-case postulation of a dropped fuel assembly.
Each spent fuel storage rack, empty or loaded with fuel, is designed to withstand earthquake loading to minimize distortion of the spent fuel storage arrangement.
IlOLTEC Report 111971708 shows that for conditions of normal and abnormal storage in both the llOLTEC and par racks, the K-eff will remain below 0.95 (substantially suberitical) in all cases, with the proposed changes. The criticality criterion of K-effless than 0.95 is basic to the safe storage of nuclear fuel.
Additionally, the changes in k-infinity and U-235 enrichment limits have no effect on the seismic analysis contained in UFSAR Section 9.1.2.3.3, previously reviewed under Amendments 45 and 195. All fuel to be stored in the spent fuel racks is bounded by the current UFSAR seismic analysis assumptions.
Also, the decay heat loading associated with this change is bounded by the existing UFSAR analysis (submitted to support Amendment 222)in Section 9.1.2.3.2 for fuel exposures expected during two operating cycles with GE-12 (i.e., through Cycle 18 operation). A scoping study comparing the hydraulic diameters of GE-10 (existing UFSAR) and GE-12 (new fuel) concludes that large margin to pool boiling conditions (both bulk and local) will be maintained at the expected maximum discharge exposures of GE-12.
Therefore, we have concluded that the proposed revision to the DAEC Technical Specifications is acceptable.
TSCR-007 to NG-99-0049 PageIof1 ENVIRONMENTAL, CONSIDERATION l
l 10 CFR Section 51.22(c)(9) identifies certain licensing and regulatory actions which are eligible for categorical exclusion from the requirement to perform an environmental assessment. A proposed amendment to an operating license for a facility requires no l
environmental assessment if operation of the facility in accordance with the proposed amendment would not: (1) involve a significan hazards consideration;(2) result in a significant change in the types or significant increase in the amounts of any effluents that may be released ofTsite; and (3) result in a significant increase in individual or cumulative occupational radiation exposure. IES Utilities Inc. has reviewed this request and determined that the proposed amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR Section 51.22(c)(9). Pursuant to 10 CFR Section 51.22(b),
no environmentai impact statement or environmental assessment needs to be prepared in connection with the issuance of the amendment. The basis for this determination follows:
Basis The change meets the eligibility criteria for categorical exclusion set forth in 10 CFR Section 51.22(c)(9) for the following reasons:
1.
As demonstrated in Attachment 1 to this letter, the proposed amendment does not involve a significant hazards consideration.
2.
There is no significant change in the types or significant increase in the amounts of any effluents that may be released otTsite. The way in which the fuel assemblies will be handled and stored is not being changed by this update in criticality requirements for storage of fuel in the spent fuel racks. The ability of the spent fuel racks to control the reactivity of the fuel bundles has been shown.
K-eff remains less than 0.95 and there are no new accidents being introduced.
3.
There is no significant increase in individual or cumulative occupational radiation exposure. For all normal and abnormal storage conditions, it has been shown that the storage of nuclear fuel assemblies in the spent fuel racks with the updated criticality requirements will maintain the K-effless than 0.95. There are no changes in fuel handling equipment, fuel storage racks, fuel handling practices, or shielding that would increase the dose rate during fuel movement.
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