ML20211F407
| ML20211F407 | |
| Person / Time | |
|---|---|
| Site: | Byron, Braidwood  |
| Issue date: | 09/25/1997 |
| From: | Hosmer J COMMONWEALTH EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9710010049 | |
| Download: ML20211F407 (7) | |
Text
.
Commonwealth rdmon Company 14(M) Opus Place
- y
.e Ikm ncrs Grm c, i1 (M15-5'OI
' September 25 1997 U. S. Nuclear Regulatory Commission Attention: Document Control Desk -
Washington D.C. 20555-0001
Subject:
Supplement to the Application for Amendment Request for Appendix A, Technical Specifications, to Facility Operating Licenses:
Byron Nuclear Power Station, Units 1 and 2 Facility Operating Licenses NPF-37 and NPF-66 NRC Docket Nos. 50-454 and 50-455 Braidwood Nuclear Power Station, Units I and 2 Facility Operating Licenses NPF-72 and NPF-77 NRC Docket No2. 50-456 and 50-457 Boron Credit in the Spent Fuel Pool 4
References:
1.
J. B. Hosmer (Comed) letter to the United States Nuclear Regulatory Commission (NRC) Document Control Desk, " Application for Amendment to Appendix A, Technical Specifications, for Facility Operating License NPF-37, NPF-66, NPF-72, and NPF-77," dated June 30,1997.
2.
G. F. Dick, Jr. (NRR) letter to 1. M. Johnson, " Request for Additional Information Regarding Credit for Soluble Boron in the Spent Fuel Pool-Byron and Braidwood Stations, Units 1 and 2 (TAC Nos. h199170, h199171, hi99168 and hi99169)," dated August 1,1997.
In Reference 1, Commonwealth Edison (Comed) requested an amendment for Byron Units 1 and 2 and Braidwood Units 1 and 2. The proposed change affects' Technical Specification (TS) j Section 3.9.11,5.6.1.1, and 6.9.10 to allow Comed to permanently take credit for soluble boron
/
in the spent fuel storage pool water to maintain an acceptable margin of suberiticality. In
)
Reference 2, the NRC transmitted a request for additional information (RAI) concerning the amendment request. Per this submittal, Comed is responding to the Reference revising the Technical Specification submittal based on Comed's RAI :.,sonse (attached).
/
The changes to the original submittal are described in detail in Attachment A. Revised Technical Specification mark-up pages are in Attachments B-1 and B-2 for Byron and Braidwood, respectively, including a revised Insert B for TS page 5-5. These revisions supersede the corresponding pages in the original request (Reference 1). A review of the original Attachment C, " Evaluation of Significant Hazards Considerations," indicates the evaluation remains valid for hbfbk!!k bh.
4~
A l'nicom Company
the additional changes proposed in the supplement.
To the best of my knowledge the statements contained in this document are true and correct.
Please address any questions to Marcia Lesniak, Nuclear Licensing Administrator at (630) 663 6484.
Sincerely,
$0 John B. Hosmer Vice President Engineering Attachments
. cc:
A.B. Beach, Regional Administrator - Rill S.D. Burgess, Senior Resident Inspector - Byron C.F. Phillips, Senior Resident inspector - Braidwood G.F. Dick, Jr., Project Manager - NRR Office of Nuclear Safety -IDNS Signed efore me this c#f"
- day, l!
OFFICIAL SEAL of 4 o h et
.1997, ll MARY JO YACK
%, f40T AHY PUBLIC, ST ATE OF ILLINolts
- by,
- W m u, o, rws.
l uv couuission Exeincs.nnn L;'=""= ^ ^ ^"="== g Notary Pub}Mj
(/
m
o.
Response to the NRC's Request for Additional Information Credit for Soluble Boron in the Spent Fuel Pool Commonwealth Edison Company Byron Station, Units 1 and 2, and Braidwood Station, Units 1 and 2 Docket Nos. STN 50-454, STN 50-455, STN 50-456, and STN 50-457
-(
- 1. Since the new analysis still requires a maximum reference fuel assembly k-infinity no greater than 1.470 to meet the integral fuel burnable absorber (IFBA) requirements, why isn't k-infinity retained in technical specification (TS) 5.6.1.1?
The current Technical Specification (TS) allows the use of various combinations oflFBA and enrichments to meet spent fuel rack storage requirements. For the purpose of bounding all such allowable combinations, a limiting maximum reference fuel assembly k-infinity of 1.470 was used. With the proposed TS, this maximum k-infinity is no longer required because there are only two choices ofIFBA and fuel assembly enrichment combinations that will be allowed unrestricted storage in Region 1:
a) When a new or spent fuel assembly's initial enrichment is between 4.70 weight percent and 5.00 weight percent, a minimum 16 pin IFBA with at least 1.0X loading (equal to 1.5 mg ' B/in)is required to be present in each fuel assembly to be allowed unrestricted storage in the Region I racks.
b) When a new or spent fuel assembly's initial enrichment is 4.70 weight percent or less, there are no IFBA requirements.
The above IFB A requirements are contained in Table 4 of CAC-97-162, " Byron and Braidwood Spent Fuel Rack Criticality Analysis Using Soluble Boron Credit," dated May 1997.
- 2. Are new fuel assemblies immediately stored in the spent fuel pool upon arrival onsite?
If'not, TS 5.6.1.2 for new fuel storage should be revised to require that k-effin the new fuel storage racks remains less than or equal to 0.95 if fully flooded with unborated water and less than or equal to 0.98 iflow-density optimum density is assumed.
Although new assemblies are not routinely immediately placed into the Spent Fuel Pool (SFP) upon arrival onsite, if the new assemblies meet the storage requirements of the SFP, they may be immediately placed there.
The current wording of TS 5.6.1.2. states, "The kefT for new fuel for the first core loading stored dry in the spent fuel storage racks shall not exceed 0.98 when aqueous foam moderation is assumed." This specification only addresses use of the SFP for "the first core loading" and no other. It was intended primarily for use at Braidwood Station as it was anticipated that the new fuel for both units would arrive afler the new racks were installed and both units would be fueled with the SFP in the dry condition.
The subject TS change request does not change or alter the current New Fuel Storage Vault analysis or requirements. The subject TS change request only addresses changes necessary to compensate for the degradation of Boraflex in the SFP. There is n. Boraflex in the New Fuel Storage Vaults, and, therefore, no compensatory actions are necessary.
Although TS 5.6.1.2 is not applicable at this time in the station's life, it remains a valid and correct specification. Improvements meant to remove unnecessary or outdated specifications were made in the Improved Technical Specifications (ITS) package submitted December 13, 1996.
- 3. The boron concentration specified in TS 5,6.1.1.c should be the total soluble boron credit required to maintain k-effless than or equal to 0.95 without considering accidents (550 ppm). While the boron concentration of 2000 ppm in TS 3.9.11 is the starting point for the boron dilution analysis to show that dilution to 550 ppm is highly unlikely and the total soluble boron credit required with accidents (1650 ppm) is used to ascertain that the minimum boron concentration in the pool as required by TS 3.9.11 is sufficient to maintain k-efTno greater than 0.95 under accident conditions using double contingency, based on the licensee's analysis, the appropriate value for TS 5.6.1.1.c is 550 ppm.
TS 5.6.1.1,c will be revised to incorporate the 550 ppm boron concentration.
i U
- 4. Reference to the " CRITICALITY ANALYSIS OF HYRON AND BRAIDWOOD STATION FUEL STORAGE RACKS" in TS 5.6.1.1.e, g, and h and in TS 6.9.1.10 is not appropriate. The TS should either refer to an approved report, including title, specific identifier (e.g., WCAP), revision and date; or the TS themselves should contain the appropriate parameters; number of required IFHA (5.6.1.1.e), applicable checkerboard configurations (5.6.1.1.g), interface requirements (5.6.1.1.h).
TS 5.6.1.1.e, TS 5.6.1.1.g, and TS 5.6.1.1.h will be revised to include reference to the Byron-and Braidwood-specific criticality analysis: CAC-97-162," Byron and Braidwood Spent Fuel Rack Criticality Analysis Using Soluble Boron Credit," dated May 1997. An additional occurrence of the " CRITICALITY ANALYSIS OF BYRON AND BRAIDWOOD STATION FUEL STORAGE RACKS" appears in TS 5.3.1 and will be revised to refer to the specific analyses as well. Finally, as fuel enrichment limits for storage are contained in TS 5.6.1.1, TS Definition 1.9a and TS 6,9.1.10 will be deleted.
ATTACilMENT A DISCUSSION OF ADDITIONAL PROPOSED CliANGES BORON CREDIT IN TiiE SPENT FUEL POOL Commonwealth Edison (Comed) proposes to make the following additional changes to the proposed Byron and Braidwood Technical Specifications (TS) for Boron Credit in the Spent Fuel Pool. The changes apply to the request transmitted on June 30,1997. These changes are based on Comed's response to the NRC's August 1,1997 request for additionalinformation (RAI).
- 1. The original proposed TS Design Features 5.6.1.1.c stated that the spent fuel storage racks would maintain a k.a s 0.95 if fully flooded with water borated to 2000 ppm. The proposed revision changes the concentration to 550 ppm, which is the boron concentration required to maintain k.a less than or equal to 0.95 without considering accidents. Insert B for the Braidwood mark up of TS 5.6.1.1.c stated "A k.g< 0.95 if fully.. " This is being revised to correct a typographical error by stating, "A k.as 0.95 if fully.
- 2. The original proposed TS Design Features 5.6.1.1.e, g, and h, and TS 5.3.1, refer to a document referenced by definition 1.9a and TS Administrative Controls 6.9.1.10 -
l CRITICALITY ANALYSIS OF BYRON AND BRAIDWOOD STATION FUEL STORAGE RACKS. The proposed revision replaces this analysis reference with the Byron-and Braidwood-specific criticality analysis that incorporates a soluble boron credit:
CAC-97-162, " Byron and Braidwood Spent Fuel Rack Criticality Analysis Using Soluble j
Boron Credit," dated May 1997. Additionally, as TS 5.3.1 addresses the New Fuel Storage Vaults, TS 5.3.1. will also reference " Criticality Analysis of the Byron /Braidwood Fresh Fuel Racks," dated June 1989. This analysis was included in the original criticality analysis and was reviewed per the Safety Evaluation for Byron and Braidwood Units 1 and 2 per Amendments 29 and 18, respectively.
- 3. The original proposed TS Administrative Controls 6.9.1.10 retained reference to the document CRITICALITY ANALYSIS OF BYRON AND BRAIDWOOD STATION FUEL STORAGE RACKS. This document is also defined in TS Definitions 1.9a, and was approved ror Byron and Braidwood Units 1 and 2 per Amendments 29 and 18, respectively. These amendments replaced the cycle-specific maximum enrichment values for reload fuel with a reference to the report (titled above). As fuel enrichment limits for storage are contained in TS 5.6.1.1 and reference the Byron-and Braidwood-specific criticality analysis, TS 1.9a and TS 6.9.1.10 are no longer required. The proposed revision deletes TS 1.9a and TS 6.9.1.10.
l m
o
A'ITACHMENT B 1 MARKED UP PAGES FOR SUPPLEMENT TO PROPOSED CilANGES TO APPENDIX A, TECHNICAL SPECIFICATIONS, OF FACILITY OPERATING LICENSES NPF-37 and NPF-66 BORON CREDIT IN TIIE SPENT FUEL POOL i
BYRON STATION UNITS 1 & 2 REVISED PAGES:
Table of Contents 1
Table of Contents XX l-2 5-4 6-23 1
.