ML20134N778

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Proposed Tech Specs Revising TS 3.9.11,5.6.1.1 & 6.9.1.10 to Allow Util to Take Credit for Soluble Boron in Spent Fuel Storage Pool Water in Maintaining Acceptable Margin of Subcriticality
ML20134N778
Person / Time
Site: Byron, Braidwood  Constellation icon.png
Issue date: 11/05/1996
From:
COMMONWEALTH EDISON CO.
To:
Shared Package
ML20134N767 List:
References
NUDOCS 9611270105
Download: ML20134N778 (24)
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Text

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ATTACHMENT B MARKED UP PAGES FOR PROPOSED CHANGES TO APPENDIX A TECHNICAL SPECIFICATIONS OF FACILITY OPERATING LICENSES NPF-37, NPF-66, NPF-72, AND NPF-77 BYRON STATION UNITS 1 & 2 BRAIDWOOD STATION UNITS 1& 2 REVISED PAGES: REVISED PAGES:

3/4 9-13 3/4 9-13 5-5 5-5 6-23 6-23 l

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10 9611270105 961105 PDR ADOCK 05000454 P PDR

/Bavon len e mMal REFUELING OPERATIONS 3/4.9.11 WATER LEVEP- STORAGE POOL

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LIMI, TING _ CONDITION FOR OPERATION 3.9.11 At least 23 feet of water shall be maintained over the to o irradiated fuel assemblies seated in the storage racks. Ty,yf 4 APPLICABILITY: Whenever irradiated fuel assemblies are in the storage pool.

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ACTION:

a. With thev requirements of the above specification not satisfied, suspend all movement of fuel assemblies and crane operations with loads in the fuel storage areas and restore the water level to i within its limit within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.

The provisions of Specification 3.0.3 are not applicable.

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c.

SURVEILLANCE REQUIREMENTS 4.9.11 The water level in the storage pool shall be d6termined to be at least its minimum required depth at least once per 7 days when irradiated fuel assemblies are in the fuel storage pool.

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BYRON - UNITS 1 & 2 3/4 9-13 AMENDMENT NO.

INSERT A The dissolved boron concentration of the water in the storage pool shall be maintained at greater than or equal to 2000 ppm.

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INSERT B

b. With the boron concentration requirements of the above specification not satisfied, suspend all movement of fuel assemblies and crane operations with loads in the fuel  ;

storage areas and immediately take action to restore the dissolved boron concentration to within its limit as soon as possible.*

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DESIGN FEATURES 5.6 FUEL STORAGE CRITICALITY r

5.6.1.1 The spent fuel storage racks are designed and shall be maintained with incYu less than or equal to 0.95 when flooded with unborated waterT which a k ' des aThis of the UFSAR.

conservative allowance for uncertainties as desc is ensured by controlling fuel assembly placement in each region as follows: '

a. REGION 1
1. A nominal 10.32 inch north-south and 10.42 inch east-west, center-to-center distance is maintained between fuel assemblies placed in the spent fuel storage racks.  !
2. Fuel assemblies may be stored in this region with a) a maximum nominal initial U-235 enrichment of less than or ,

equal to 4.2 weight percent, or /

b) a maximum nominal initial U-235 enrichment of 5.0 weight percent with sufficient Integral Fuel Burnable Absorbers present in each fuel assembly such that the maximum reference fuel assembly km is less than or equal to 1.470 at 68'F.

b. REGION 2 1.

A nominal 9.03 inch center-to-center distance is maintained between fuel assemblies placed in the spent fuel storage racks.

2. a) Fuel assemblies may be stored in this region with a maximum nominal initial U-235 enrichment of 1.6 weight percent with no burnup and up to 5.0 weight percent U-235 with a minimum discharge burnup as specified in Figure 5.6-1, or b) Fuel assemblies with a maximum nominal initial U-235 enrichment of greater than 1.6 and less than or equal to f 4.2 weight percent that do not meet the minimum burnup specified in Figure 5.6-1, shall be loaded in a checkerboard pattern for storage in this region, i

5.6.1.2 The k,, for new fuel for the first core loading stored dry in the spent fuel stora,ge racks shall not exceed 0.98 when aqueous foam moderation is assumed.

DRAINAGE 5.6.2 The spent fuel storage pool is designed and shall be maintained to prevent inadvertent draining of the pool below elevation 423 feet 2 inches.

CAPACITY 5.6.3 The spent fuel storage pool is designed and shall be maintained with a i storage capacity limited to no more than 2870 fuel assemblies.

Insaf C BYRON - UNIT I&2 5-5 Amendment No.

INSERT C Until December 31, 1997, the spent fuel storage racks shall be maintained with a Keff of less than or equal to 0.95 when flooded with water containing a minimum of 2000 ppm soluble boron.

In addition to the burnup requirements currently contained in Specification 5.6.1.1, the requirements of CAC-96-248, " Byron and Braidwood Spent Fuel Rack Criticality Analysis with Credit for Soluble Boron," will be satisfied.

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ADMINISTRATIVE CONTROLS CRITICALITY ANALYSIS OF BYRON AND BRAIDWOOD STATION FUEL STORAGE RACKSY 6.9.1.10 Fuel er.richment limits for storage shall be established and documented in the CRITICALITY ANALYSIS OF BYRON AND BRAIDWOOD STATION FUEL STORAGE RACKS. The analytical methods used to determine the maximum fuel enrichments shall be those previously reviewed and approved by the NRC in

" CRITICALITY ANALYSIS OF BYRON AND BRAIDWOOD STATION FUEL STORAGE RACKS." The fuel enrichment limits for storage shall be detemined so that all applicable limits (e.g. , subcriticality) of the safety analysis are met.

The CRITICALITY ANALYSIS OF BYRON AND BRAIDWOOD STATION FUEL STORAGE RACKS report shall be provided upon issuance of any changes, to the NRC Document Control Desk, with copies to the Regional Administrator and the Resident Inspector. ,

SPECIAL REPORTS 6.9.2 Special reports shall be submitted to the Regional Administrator of the NRC Regional Office within the time period specified for each report.

6.10 RECORD RETENTION ,

In addition to the applicable record retention requirements of Title 10, Code of Federal Regulations, the following records shall be retained for at i least the minimum period indicated.

6.10.1 The following records shall be retained for at least 5 years:

a. Records and logs of unit operation covering time interval at each power level;
b. Records and logs of principal maintenance activities, inspections, repair and replacement of principal items of equipment related to nuclear safety;
c. All REPORTABLE EVENTS;
d. Records of surveillance activities, inspections, and calibrations required by these Technical Specifications;
e. Records of changes made to the procedures required by Specification 6.8; /I ,
f. Records of radioactive shipn nts; i
g. Records of sealed source and fission detector leak tests and results; and
h. _ Records of annual physical inventory of all sealed source material of record.

6.10.2 The following records shall be retained for the duration of the unit Operating License:

a. Records and drawing changes reflecting unit design modifications made to systems and equipment described in the Final Safety Analysis Report; LigyD b. Records of new and irradiated fuel inventory, fuel transfers and assembly burnup histories; BYRON - UNITS 1 & 2 6-23 AMENDMENT NO. 5 h

i INSERT D l l

In addition to the burnup requirements contained in the currently approved criticality analysis, the requirements of CAC-96-248, " Byron and Braidwood Spent Fuel Rack Criticality Analysis with Credit for Soluble Boron," will be satisfied.

These requirements will be in effect until December 31, 1997.

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REFUELING OPERATIONS

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3/4.9.11 WATER LEVEL - STORAGE POOL l

LIMITING CONDITION FOR OPERATION I

3.9.11 At least 23 feet of water shall be maintained over the of 3 .  ;

irradiated fuel assemblies seated in the storage racks. Jg,g /}

APPLICABILITY: Whenever irradiated fuel assemblies are in the storage pool. l

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ACTION:

a. With th requirements of the above specification not satisfied, suspend all movement of fuel assemblies and crane operations with loads in the fuel storage areas and restore the water level to 14pyf. $ within its limit within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.

/.f,.The provisions of Specification 3.0.3 are not applicable.

7 SURVEILLANCE REQUIREMENTS 4.9.11 The water level in the storage pool shall be determined to be at least its minimum required depth at least once per 7 days when irradiated fuel assemblies are in the fuel storage pool.

t{,1,II. a Boram coaca/mkm in +4e eknre pa ! e ka le '

hhvHned k be. 7re6 fAu eg ad k 2 ac36ppn af Isst once ye, 2 y k,u ,,y 1

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  1. 7kese. rq u*e*h sidl be in e%) &I 8uA 'Ib MI I BRAIDWOOD - UNITS 1 & 2 3/4 9-13 AMENDMENT NO. Jf(

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INSERT A The dissolved boron concentration of the water in the storage l pool shall be maintained at greater than or equal to 2000 ppm.

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I INSERT B l

b. With the boron concentration requirements of the above <

specification not satisfied, suspend all movement of fuel i assemblies and crane operations with loads in the fuel storage areas and immediately take action to restore the dissolved boron concentration to within its limit as soon as possible.* l l

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t DESIGN FEATURES ,

5.6 FUEL STORAGE CRITICALITY 5.6.1.1 The spent fuel storage racks are designed and shall be mahtained with ak less than er equal to 0.95 when flooded with unborated water 7 which inc%es a conservative allowance for uncertainties as described in section s.1, of the UFSAR. This is ensured by controlling fuel assembly placement in each /

region as follows: I

a. REGION 1
1. A nominal 10.32 inch north-south and 10.42 inch east-west, center-to-center distance is maintained between fuel assemblies placed in the spent fuel storage racks.
2. Fuel assemblies may be stored in this region with a) a maximum nominal initial U-235 enrichment of less than or j equal to 4.2 weight percent, or f.

el b) a maximum nominal initial U-235 enrichment of 5.0 weight percent with sufficient Integral Fuel Burnable Absorbers present in each fuel assembly such that the maximum 1 reference fuel assembly k= is less than or equal to 1.470 f/

at 60*F. / l

b. REGION 2 l 1. A nominal 9.03 inch center-to-center distance is maintained L between fuel assemblies placed in the spent fuel storage racks.
2. a) Fuel assemblies may be stored in this region with a maximum
nominal initial U-235 enrichment of 1.6 weight percent with l no burnup and up to 5.0 weight percent U-235 with a minimum discharge burnup as specified in Figure 5.6-1, or 4

i b) Fuel assembliss with a maximum nominal initial 11-235 i enrichasut wf greater than 1.5 and less then or equal to 4.2 weight percent that do not meet the minimus Aurnup specified in Figure 5.6-1, shall be loaded in a j i checkerboard pattern for storage in this region. [

l 5.6.1.2 The k,,, for new fuel for the first core loading stored dry in the j spent fuel storage racks shall not exceed 0.98 when aqueous foam moderation is assumed.

DRAINAGE 5.6.2 The spent fuel storage pool is designed and shall be maintained to l

prevent inadvertent draining of the pool below elevation 423 feet 0 inches.

4 CAPACITY 5.6.3 The spent fuel storage pool is designed and shall be maintained with a

storage capacity limited to no more than 2870 fuel assemblies.

, MJek (

5-5 Amendment No.

BRAIDWOOD - UNITS 1 & 2 1

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INSERT C Until December 31, 1997, the spent fuel storage racks shall be maintained with a Keff of less than or equal to 0.95 when flooded with water containing a minimum of 2000 ppm soluble boron.

In addition to the burnup requirements currently contained in Specification 5.6.1.1, the requirements of CAC-96-248, " Byron and Braidwood Spent Fuel Rack Criticality Analysis with Credit for Soluble Boron," will be satisfied.

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ADMINISTRATIVE CONTROLS CRITICALITYANALYSISOFBYRONANDBRAIDWOODSTATIONFUELSTORAGERACKSk 6.9.1.10 Fuel enrichment limits for storage shall be established and documented in the CRITICALITY ANALYSIS OF BYRON AND BRAIDWOOD STATION FUEL STORAGE RACKS. The analytical methods used to determine the maximum fuel enrichments shall be those previously reviewed and approved by the NRC in

" CRITICALITY ANALYSIS OF BYRON AND BRAIDWOOD STATION FUEL STORAGE RACKS." The fuel enrichment limits for storage shall be determined so that all applicable l limits (e.g., subcriticality) of the safety analysis are met.

The CRITICALITY ANALYSIS OF BYRON AND BRAIDWOOD STATION FUEL STORAGE l RACKS report shall be provided upon issuance of any changes, to the NRC l Document Control Desk, with copies to the Regional Administrator and the Resident Inspector. .

SPECIAL REPORTS 6.9.2 Special reports shall be submitted to the Regiona' Auministrator of the NRC Regional Office within the time period specified for each report.

6.10 RECORD RETENTION In addition to the applicable record retention requirements of Title 10, Code of Federal Regulations, the following records shall be retained for at least the minimum period indicated.

6.10.1 The following records shall be retained for at least 5 years:

a. Records and logs of unit operation covering time interval at each power level;
b. Records and logs of principal maintenance activities, inspections, repair and replacement of principal items of equipment related to nuclear safety;
c. All REPORTABLE EVENTS;
d. Records of surveillance activities, inspections, and calibrations required by these Technical Specifications;
e. Records of changes made to the procedures required by /

d Specification 6.8;

f. Records of radioactive shipments;  !

. s g. Records of sealed source and fission detector leak tests and results; and

h. Records of annual physical inventory of all sealed source material of record.

6.10.2 The following records shall be retained for the duration of the unit Operating License:

a. Records and drawing changes reflecting unit design modifications made to systems and equipment described in the Final Safety Analysis Report;
b. Records of new and irradiated fuel inventory, fuel transfers and 2 Ned b assembly burnup histories; BRAIDWOOD - UNITS 1 & 2 6-23 AMENDMENT NO. b/

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  • In addition to the burnup requirements contained in the currently approved criticality analysis, the requirements of CAC-96-248, " Byron and Braidwood Spent Fuel Rack Criticality Analysis with Credit for Soluble Boron," will be satisfied.

These requirements will be in effect until December 31,

! 1997.  ;

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ATTACHMENT C EVALUATION OF SIGNIFICANT HAZARDS CONSIDERATIONS FOR PROPOSED CHANGES TO APPENDIX A TECHNICAL SPECIFICATIONS OF FACILITY OPERATING LICENSES NPF-37, NPF-66, NPF-72, AND NPF-77 Commonwealth Edison has evaluated this proposed amendment and determined that it involves no significant hazards considerations. According to Title 10 Code of Federal Regulations Section 50 Subsection 92 Paragraph c (10 CFR 50. 92 (c)), a proposed amendment to an operating license involves no significant hazards considerations if operation of the facility in accordance with the proposed amendment would not:

1. Involve a significant increase in the probability or consequences of an accident previously evaluated; or
2. Create the possibility of a new or different kind of accident from any accident previously evaluated; or
3. Involve a significant reduction in a margin of safety.

A. INTRODUCTION Commonwealth Edison (Comed) proposes to revise Byron and Braidwood Technical Specifications (TS) 3.9.11, " Water Level-Storage Pool," 5.6.1.1, " Criticality," and 6.9.1.10, " Criticality Analysis of Byron and Braidwood Station Fuel Storage Racks."

These revisions will allow Comed to take credit for soluble boron in the spent fuel storage pool water in maintaining an acceptable margin of subcriticality in the Spent Fuel Pool (SFP), and will provide appropriate controls to ensure the dissolved boron concentration in the SFP water is adequately maintained. These changes are temporary in nature and are required to compensate for the degradation of the Boraflex panels in the spent fuel storage cells while long term corrective actions for this problem are implemented. These changes will be in effect for a maximum of 1 year.

B. NO SIGNIFICANT HAZARDS ANALYSIS 15 l

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1. The proposed change does not involve a significant increase in the probability or consequences of an accident previously l evaluated.

The changes proposed in this request implement a minimum SFP boron concentration requirement, and establish controls to ensure that this minimum concentration is always satisfied. Soluble boron has always been present in the SFP water.

The accidents previously evaluated for the SFP are:

l 1. Dropped fuel assembly, i

2. Accidental misloading of a fuel assembly, and
3. Loss of normal cooling of the SFP.

The presence of soluble boron, at any concentration, in the SFP j water is not considered as a precursor to any of these accidents, 1 and, therefore, these proposed changes do not result in an I increase in the probability of occurrence of any accident previously analyzed.

The physical design of the SFP storage racks prevents inadvertent criticality in the event of a dropped fuel assembly. For an assembly dropped on top of the fuel racks, the rack structure is i not excessively deformed, and the dropped assembly, which comes i to rest horizontally on top of the the rack, has sufficient water separating it from the active fuel height of the stored assemblies to preclude neutronic interaction. Design of the spent fuel racks and fuel handling equipment is such that it precludes the insertion of a fuel assembly between the rack modules. The dropping of a fuel assembly between the fuel racks and the SFP wall is bounded by the misloaded assembly accident discussed below. The minimum water level requirements mitigate the possibility of a radioactive material release if a fuel I assembly is dropped. Thus, the presence of soluble boron does not affect the consequences of this accident.

In the event of a fuel assembly misloading or a loss of normal cooling, the minimum boron concentration specified in this proposed change will ensure that Ken remains less than or equal to 0.95 following these events. Thus, these proposed changes do not result in an increase in the consequences of these accidents.

Therefore, these proposed revisions do not result in a significant increase in the probability or consequences of an accident previously analyzed.

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2. The proposed change does not create the possibility of a new or different kind of accident from any accident previously evaluated.

These proposed changes do not create any new operating conditions or modes for the SFP. Soluble boron has always been present in the SFP. In the Safety Evaluation Report (SER) for the Byron and Braidwood Spent Fuel Pool Re-Back amendment, the Nuclear Regulatory Commission determined that a minimum of 300 ppm boron was required to ensure that K,rt would be less than or equal to 0.95 in a misloaded assembly event. The SER then takes credit for the presence of 2000 ppm soluble boron in satisfying this requirement.

Since soluble boron has always been present in the SFP water, the possibility of a SFP dilution has always existed. In order to preclude the possibility of a SFP dilution accident during the interim period of the Technical Specification Amendment, Byron and Braidwood will implement compensatory measures including the  ;

following:

1. Appropriate procedures will be changed to reflect the requirement to maintain a minimum of 2000 ppm soluble boron in the SFP.
2. Use of the Reverse Osmosis Unit for silica removal has been restricted to slow the rate of Boraflex dissolution.
3. SFP level loss procedure will be revised to clearly state that non-borated emergency makeup sources must be used only as a last resort.
4. In addition, station surveillances for monitoring of the SFP parameters will be performed with sufficient periodicity to allow for prompt corrective actions to preclude a SFP dilution accident.

Also, some checkerboarding of spent fuel assemblies in both the Byron and Braidwood SFPs will be undertaken in accordance with CAC-96-248, " Byron and Braidwood Spent Fuel Rack Criticality Analysis with Credit for Soluble Boron," October 1996, to ensure that SFP Kort will remain less than 1.0 without credit for soluble boron.

Therefore, for the period of time this Technical Specification Amendment is in place, there is no possibility of a new accident.

This amendment request will not result in the installation of any new equipment or modification of any existing equipment. Thus, 17

this amendment does not create the possibility of a new or different kind of accident from any accident previously evaluated.

3. The proposed change does not involve a significant reduction in a margin of safety.

Soluble boron has always been present in the SFP water. This amendment request creates a minimum boron concentration requirement for the SFP and establishes controls to ensure that this minimum concentration is always satisfied. These limits and controls will ensure that the SFP Ktr remains less than or equal to 0.95. ,

i In order to minimize the possibility of loss of significant amounts of boron from the SFP, Comed has established compensatory :

measures to minimize the potential for SFP dilution. In the unlikely event of a loss of boron from the SFP, storage configurations have been identified and will be implemented to ensure that K,tr remains less than 1.0 even if all the soluble boron is lost.

Thus, this amendment request does not result in a significant decrease in a margin of safety.

Therefore, based on the above evaluation, Comed has concluded that these changes involve no significant hazards considerations.

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ATTACHMENT D i ENVIRONMENTAL ASSESSMENT FOR PROPOSED CHANGES TO APPENDIX A TECHNICAL SPECIFICATIONS OF FACILITY OPERATING LICENSES NPF-37, NPF-66, NPF-72, AND NPF-77 Commonwealth Edison Company (Comed) has evaluated this proposed license amendment request against the criteria for identification of licensing and regulatory actions requiring environmental assessment in accordance with Title 10, Code of Federal Regulations, Part 51, Section 21 (10 CFR 51.21). ContEd has determined that this proposed license amendment request meets the criteria for a categorical exclusion set forth in 10 CFR 51. 22 (c) ( 9) . This determination is based upon the following:

1. The proposed licensing action involves the issuance of an amendment to a license for a reactor pursuant to 10 CFR 50 which changes a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, or which changes an inspection or a surveillance requirement. This proposed license amendment request will allow Comed to take credit for soluble boron in the spent fuel storage pool water in maintaining an acceptable margin of subcriticality, and will provide appropriate controls to ensure the dissolved boron concentration in the spent fuel storage pool water is I adequately maintained; 1
2. this proposed license amendment request involves no l significant hazards considerations; 1
3. there is no significant change in the types or significant increase in the amounts of any effluent that may be released offsite; and
4. there is no significant increase in individual or cumulative occupational radiation exposure.

Therefore, pursuant to 10 CFR 51.22 (b) , neither an environmental impact statement nor an environmental assessment is necessary for this proposed license amendment request.

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l ATTACHMENT E CAC-96-248 BYRON AND BRAIDWOOD SPENT FUEL RACK CRITICALITY ANALYSIS WITH CREDIT FOR SOLUBLE BORON l

OCTOBER 1996 l

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Westinghouse. ' Energy Systems g5]p ena 15230-0355 Electric Corporation October 31,1996 i

- 96CB-G-0171 Mr. W. Funke i

Commonwealth Edison Company Nuclear Fuel Services  :

1400 Opus Place - Suite 400 ,

Downers Grove,IL 60515 1 Refs: 1) 96CB-G 0151,10/1/96

2) 96CB-G-0169,10/29/96

Dear Mr. Funke:

i COMMONWEALTH EDISON COMPANY BYRON /BRAIDWOOD NUCLEAR POWER PLANT .

FINAL REPORT AND CALCULATION NOTE FOR BORON CREDIT ANALYSIS Attached is the Byron /Braidwood Boron Credit Analysis which integrates your comments into  :

our draft report of Reference 1. I have also attached the final calc note relative to this subject  !

(other calc notes previously sent in Reference 2).

We will be revising our criticality analysis methods in the upcoming months to address recent i licensing issues. I will keep you informed on our progress in this area and on a schedule for revising the Byron /Braidwood analysis.

Please contact me on (412) 374-2112 if you require further information on this subject.

Sincerely, .

q ,' l } /C y M. J. Weber -

Project Engineer Domestic Sales & Customer Projects MJW/sh Attachment cc: D. Beddingfield W PSFS Chicago w/o att.

L. Kepley Comed Braidwood w/o att.

J. Nevling . Fuel Department w/o att. _

K. S. Petersen Fuel Department w/o att.

D. Redden w/o att.

G. Stauffer Comed Byron w/o att.

E.H. Young w/o att.

S. Yang w/o att.

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90chgD171. doc l

1 ht.r.8mme Proprietary class 2C From: CNFD Core Engineering WIN: 284-2276/2092 1 Date: October 31,1996 1

Subject:

Byron and Braidwood Spent Fuel Rack Criticality Analysis with Credit for Soluble Boron Keywords: N/A

References:

1. CN-CRIT-030, CN-CRIT-033 thm 035, and CN-CRIT-041 i

To: M. J. Weber cc: S. Kapil W. D. Newmyer Please transmit the attached report entitled " Byron and Braidwood Spent Fuel Rack Criticality Analysis with Credit for Soluble Boron" to Commonwealth Edison Company. The report shows that 17x17 OFA fuel assemblies with enrichments up to 5.0 w/o can be safely stored in the Byron and Braidwood spent fuel storage racks with credit for spent fuel pool soluble boron.

The calculations that support the attached report are listed in the Reference. All comments from Comed have been addressed in the final report.

Please direct any questions to the undersigned.

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?Y K. R. Robinson , H. Q. Lam I

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Core Analysis C Core Ana sisC l Date: jo/3g Date: 3 9g APPROVED: 6.

B. J. To sen, Manager Core Analysis C Date: gp/g) l I

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woninshouse Propnesaryclass 2c

Reference:

CAC-96-248 Byron & Braidwood Spent Fuel Rack Criticality Analysis with Credit for Soluble Baron All the action items listed in 96CB-G-0014 letter were considered in Byron and Braidwood Spent Fuel Rack Criticality analysis. Most of the results are presented in the attached draft report, except for the following items.

Evaluation of 2 elevated assemblies stored in Region 1.

' A special evaluation of the Region 1, which contains 2 elevated fuel assemblies about 6" above the BORAL, was made with the assumption that the top and bottom 6" of these two assemblies contain natural enriched blankets.

The resulted Keff is less than that of the all cell 4.8 w/o reference Keff. Therefore, it is concluded that these two assemblies can be safely stored in the Region 1 of the Byron and Braidwood spent fuel rack.

Evaluation of the failed fuel assembly storage area This analysis required the drawing for the interface between the normal Region 2 storage cells and the failed fuel assembly storage area. The analysis will be performed and transmitted in December,1996.

Region 2 storage of Failed Fuel Rod Storage Canisters (FFRSC)

The limits detennined for the Region 2 in the attached report can be applied to the FFRSC assuming the failed fuel rods stored in the FFRSC meet the enrichment and burnup limits of the storage configuration in which the FFRSC has been placed.

/k.J'.Mb.s4AY\.)

K. R. Robinson W

H.Q. Lam Core Anal sis C Core Analysis C Date: ) yf/g Date: g h

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