ML17191B412
| ML17191B412 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 08/03/1999 |
| From: | Heffley J Commonwealth Edison Co |
| To: | NRC/IRM |
| Shared Package | |
| ML17191B413 | List: |
| References | |
| JMHLTR:#99-0076, NUDOCS 9908100261 | |
| Download: ML17191B412 (9) | |
Text
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Commonwealth Edison ~any
-Dresden Generating Stat.,
6500 North Dresden Road Morris, IL 60450 Tel 815-942-2920 ComEd August 3, 1999 JMHL TR: #99,0076 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Dresden Nuclear Power Station, Units 2 and 3 Facility Operating License Nos. DPR-19 and DPR-25 NRC Docket Nos. 50-237 and 50-249
Subject:
Request for Amendment to Appendix A, Minimum Critical Power Ratio
References:
- 1. ANF-1125(P)(A), "ANFB Critical Power Correlation-ANFB."
Purpose
- 2. ANF-1125(P)(A), Supplement 1, Appendix E, Revision 0, "ANFB Critical Power Correlation Determination of ATRIUM-98 Additive Constant Uncertainties," Siemens Power Corporation, September 1998.
- 3. EMF-85-74(P) Supplement 1 (P)(A) and Supplement 2 (P)(A),
"RODEX2A (BWR) Fuel Rod Thermal-Mechanical Evaluation Model,"
Siemens Power Corporation, February 1998.
- 4. ANF-89-14(P)(A), "Advanced Nuclear Fuels Corporation Generic Mechanical Design for Advance Nuclear Fuels Corporation 9x91X and 9x9-9X BWR Reload Fuel," Revision 1, and Supplements 1 and.
2, Advanced Nuclear Fuels Corporation, October 1991.
- 5. ANF-524(P)(A), "ANF Critical Power Methodology for Boiling Water Reactors."
In accordance with 10 CFR 50.90, Commonwealth Edison Company (ComEd) proposes to amend Appendix A, Technical Specifications of Facility Operating License DPR-19 to reflect a change to the Dresden Nuclear Power Station Un.it 2 Minimum Critical Power Ratio (MCPR) Safety Limit (SL). ComEd also proposes to amend Section 6 of Appendix A, Technical Specifications of Facility Operating Licenses DPR-
. methodology.
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Background
Cycle specific calculations have been performed for the Dresden Nuclear Power Station Unit 2 Cycle 17 (D2C17) MCPR Safety Limit (SL) using the NRG-approved SPC methodology (References 1, 2, and 5). These calculations show that for cycle exposures greater than 13,999 MWd/MTU (Mega Watt days per Metric Ton Uranium), a MCPR SL of 1.12 is supportable for this cycle's core design. The current MCPR *SL of 1.09 remains applicable for cycle exposures less than 13,999 MWd/MTU. Therefore, to
-support D2C17 operation, this license amendment request proposes to conservatively increase the Unit 2 MCPR Safety Limit to 1.12 for cycle exposures greater than 13,800 MWd/MTU.
The higher MCPR S<;ifety Limit for DiC17 exposures greater than 13,999 MWd/MTU is primarily due to increased bundle exposures in the core design. The increased bundle exposures result in a significant increase in the impact of channel bow on the MCPR Safety Limit calculation. Since the channel bow impact is significant for cycle exposures greater than 13,999 MWd/MTU, ComEd is requesting this amendment to conservatively support operation beyond 13,800 MWd/MTU. Using preliminary calculations, it is anticipated that 13,800 MWd/MTU will be reaGhed approximately 97%
through D2C17.. Therefore, to support the entire D2C17 cycle, ComEd is requesting an amendment to increas.e the MCPR Safety Limit to t.12 for cycle exposures greater than 13,800 MWd/MTU.
The core design for Dresden Unit 3 Cycle 17 (D3C17), may also have fuel bundles at
- these exposure levels. If determined that the D3C17 MCPR Safety Limit needs to be increased, another amendment request will be made in a similar time frame as this
. amendment request.
RODEX2A Supplements 1.and 2, Reference 3, has be.en reviewed and approved by the NRC. This amendment request proposes to add this SPC methodology to Section 6.9.A.6.b. This methodology supports RODEX2A licensing applications up to 62,000 MWd/MTU rod-average burnup and fuel rod/assembly/channel growth models and analytical methods up to 54,000. MWd/MTU assembly-average burnup.
Schedule ComEd is requesting that this application for amendment request be reviewed and approved by the NRC Staff prior to May 15, 2000. Approval by May 15, 2000 will adequately support D2C17 operation. ComEd will implement this amendment prior to reaching a cycle exposure of 13,800 MWd/MTU.
The following outlines ComEd's proposed amendment request.
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- 1.
Attachment A provides a description and evaluation of the proposed changes to Facility Operating License DPR-19 and DPR-25.
'August 3, 1999 e Page 3 U.S. Nuclear Regulatory Commission
- 2.
Attachment B provides the marked up pages for the Dresden Nuclear Power Station Technical Specifications.
- 3.
Attachment C describes Com Ed's e_valuation performed in accordance with 1 O CFR 50.92(c), supporting a finding bf rio significant hazard considerations are involved.
- 4.
Attachment D provides the Environmental Assessment Applicability Review.
This request for amendment has been reviewed and approved in accordance with ComEd's procedures.
ComEd is notifying the State of Illinois of this application for amendment by transmitting a copy of this letter and its attachments to the designated state official.
Should you have any questions concerning this letter, please contact Mr. Dale Ambler at (815) 942-2920 extension 3800.
Respectfully, cc:
Regional Administrator - NRC Region Ill NRC Senior Resident Inspector - Dresden Nuclear Power Station
STATE OF ILLINOIS IN THE MATTER OF:
\\
COMMONWEAL TH EDISON {COM ED) COMPANY DRESDEN NUCLEAR POWER STATION - UNITS 2 & 3 AFFIDAVIT Docket Nos. 50-237 50-249 I affirm that the content of this transmittal is true and correct to the best of my knowledge, information and belief.
Subscribed and sworn to before me, a Notary Public in and for the State above named, this ___ Z-__ day of OFFICIAL SEAL LAURA KAMINSKA$
NOTARY PUBLIC, STATE OF ILLINOIS MY COMMISSION EXPIRES 6* 1 *2002
~a~sfc0 Notary Public
ATTACHMENT A DESCRIPTION AND EVALUATION OF PROPOSED CHANGES
- 1.
BACKGROUND INFORMATION This Technical Specification amendment request proposes to change the Minimum Critical Power Ratio (MCPR) Safety Limit (SL) of Dresden Nuclear Power Station Unit 2 in order to support Unit 2 Cycle 17 (D2C17) operation beyond 13,999 Mega Watt days per Metric Ton Uranium (MWd/MTU) cycle exposure. Siemens Power Corporation (SPC) has evaluated the MCPR SL for Dresden Unit 2 Cycle 17 using the Reference 1 NRG-approved correlation with the approved ATRIUM-98 additive constant uncertainty (Reference 2). The evaluation determined that the current MCPR SL of 1.09 is applicable up to a cycle exposure of 13,999 MWd/MTU and a MCPR SL of 1.12 is applicable beyond 13, 999 MWd/MTU for the D2C 17 core design. Therefore, this Technical Specification amendment request proposes to conservatively increase the MCPR SL for Unit 2 from 1.09 to 1.12 for cycle exposures greater than 13,800 MWd/MTU. Unit 2 Cycle 16 MCPR SL calculations resulted in a MCPR SL of 1.09 for two loop operation and 1.1 O for single recirculation loop operation, with less then 0.1 % of the rods predicted to experience boiling transition (SER dated April 10, 1998). The MCPR SL will remain at 1.09 up to a cycle exposure of 13,800 MWd/MTU and is being increased to 1.12 for a cycle exposure beyond 13,800 MWd/MTU for two loop operation. The D2C17 MCPR SL for single recirculation loop operation is 1.10 for a cycle exposure up to 13,800 MWd/MTU and 1.13 beyond 13,800 MWd/MTU. Therefore, to support single loop operation, increasing the requested MCPR SL by 0.01 remains applicable. Cycle specific MCPR calculations will be performed for future reloads, consistent with SPC's NRG-approved methodology.
This Technical Specification amendment request also proposes to add Reference 3 to Section 6.9.A.6.b. Reference 3, EMF-85-74, Revision 0, Supplements 1 and 2 (P)(A), is an NRC-approved methodology which increased the burnup limit for RODEX2A applications from 60,000 MWd/MTU (peak pellet) to 62,000 MWd/MTU (rod-average}, and increased the assembly-average burnup limit from 48,000 to 54,000 MWd/MTU for the models and methods specific to ~he ATRIUM 9 and ATRIUM 10 fuel designs. Both units are operating* with ATRIUM-98 fuel. Therefore, adding Reference 3 to Section 6.9.A.6.b will permit use of the extended burnup limits for both Dresden Nuclear Power Station operating units.
- 2.
DESCRIPTION OF THE PROPOSED CHANGES This license amendment request proposes to change the MCPR SL for Dresden Nuclear Power Station Unit 2 and add the Reference 3 methodology to Section 6.
The Dresden Nuclear Power Station Unit 2 MCPR SL is currently 1.09 and is proposed to be increased to 1.12 for cycle exposures greater than 13,800 MWd/MTU. The MCPR SL is increased for Dresden Nuclear Power Station Unit 2 to support D2C17 operation beyond a cycle exposure.of 13,800 MWd/MTU. Therefore, this amendment request proposes to change
. Section 2.1.B of the Dresden Nuclear Power Station Technical Specifications to the following:
Attachment A Pagel of 5
ATTACHMENT A DESCRIPTION AND EVALUATION OF PROPOSED CHANGES The MINIMUM CRITICAL POWER.RA TIO (MCPR) shall not be less than the following:
Unit 2:
Unit 3:
1.09 for cycle exposures less than or equal to 13,800 MWd/MTU and 1.12 for cycle exposures greater than 13,800 MWd/MTU, and 1.10 with the reactor vessel steam dome pressure greater than or equal to 785 psig and core flow greater than or equal to 10% of rated flow. During single recirculation loop operation, the MCPR limit shall be increased by 0.01.
The addition of Reference 3 to Section 6 supports the increased burnup limits for RODEX2A applications for ATRIUM 9 and 10 designs. Since Dresden Nuclear Power Station currently has ATRIUM-98 fuel in both Units, the addition of the Reference 3 methodology will permit the use of the extended burnup limits in core design and operation. The Reference 3 methodology is NRC-approved and is requested to be included as Reference 13 into Section 6.9.A.6.b as follows.
- 13.
EMF-85-74(P), RODEX2A (8WR) Fuel Rod Thermal-Mechanical Evaluation Model, Supplement 1 (P)(A) and Supplement 2 (P)(A), Siemens Power Corporation, February 1998.
- 3.
DESCRIPTION OF THE CURRENT REQUIREMENTS The current requirements for Dresden Nuclear Power Station, Units 2 and 3 utilize the NRC-approved SPC ANF8 critical power correlation to calculate the Critical Power Ratio for ATRIUM-98 and 9x9-2 fuel (Reference 1). The MCPR SL for Unit 2 is 1.09 and for Unit 3 is 1.10. Both Units are currently operating in Cycle 16.
The previously approved burnup limits for ATRIUM-98 fuel are 60,000 MWd/MTU peak pellet and 48,000 MWd/MTU assembly average burnup. These limits were approved in the Technical Specification Section 6.9.A.6.b Reference 8 methodology (Reference 4 of this amendment request).
- 4.
BASES FOR THE CURRENT REQUIREMENTS Currently, the MCPR SL for Dresden Nuclear Power Station Unit 2 is 1.09 and for Unit 3 is 1.1 O based on SPC's NRC-approved MCPR SL correlation and methodology (References 1 and 5). An A TRIUM-98 additive constant uncertainty that is conservative relative to Reference 2 was used for calculating the MCPR SL for both Unit 2 Cycle 16 and Unit 3 Cycle 16.
The burnup limits for ATRIUM-98 fuel are 60,000 MWd/MTU for peak pellet exposure and 48,000 MWd/MTU for assembly-average exposure. The current licensing burnup limits for SPC BWR fuel are based on theNRC-approved burriup limits established in Reference 8 of the Technical Specifications (Referer;ice 4 of this amendment request). The current approved Attachment A Page 2of5
ATTACITh1ENT A DESCRIPTION AND EV ALDA TION OF PROPOSED CHANGES burnup limits (Reference 3) are 62,000 MWd/MTU rod average and 54,000 MWd/MTU
- assembly-average exposures.
- 5.
NEED FOR THE REVISION OF THE REQUIREMENTS The Unit 2 MCPR SL is proposed to be increased from 1.09 to 1.12 for cycle exposures greaterthan 13,800 MWd/MTU. This change is requested to support D2C17 operation beyond 13,800 MWD/MTU. The results for the D2C17 MCPR SL calculation indicate that the current Unit 2 MCPR SL, 1.09, is supportable up to a cycle exposure of 13,999 MWd/MTU. However, for cycle exposures greater than 13,999 MWd/MTU the current Unit 2 MCPR SL is not supportable. For cycle exposures greater than 13,999 MWd/MTU, a MCPR SL of 1.12 for two loop operation and 1.13 for single recirculation loop operation are applicable with fewer than 0.1 % of the rods predicted to experience boiling transition.. Therefore, conservatively increasing the dual loop operation MCPR SL to 1.12 for cycle exposures greater than 13,800 MWd/MTU will support D2C17 operation beyond 13,800 MWd/MTU.
This amendment request also proposes to add Reference 3 to Section 6.9.A.6.b of the Technical Specifications. This methodology is needed to support the design and operation of future Dresden Nuclear Power Station Unit 2 and 3 reloads containing A TRIUM-98 fuel. The Reference 3 NRG-approved methodology permits the use of extended burnup limits for ATRIUM 9 and 10 designs. Therefore, adding Reference 3 to Section 6.9.A.6.b will support design and operation of future reloads containing ATRIUM-98 fuel.
Attachment A Page 3 of 5
ATTACHMENT A DESCRIPTION AND EVALUATION OF PROPOSED CHANGES
. 6.
- DESCRIPTION OF THE REVISED REQUIREMENTS This amendment proposes to increase the Dresden Nuclear Power Station Unit 2 MCPR SL from 1.09 to 1.12 for exposures greater than 13,800 MWd/MTU. All MCPR surveillance requirements remain unchanged. This request for amendment proposes the following wording for Technical Specification Section 2.1.B.
2.1.B The MINIMUM CRITICAL POWER RATIO (MCPR) shall not be less than the following:
Unit 2:
Unit 3:
1.09 for cycle exposures less than or equal to 13,800 MWd/MTU and 1.12 for cycle exposures greater than 13,800 MWd/MTU, and 1.10 with the reactor vessel steam dome pressure greater than or equal to 785 psig and core flow greater than or equal to 10% of rated flow. During single recirculation loop operation, the MCPR limit shall be increased by 0.01.
This request for amendment proposes the following reference to be included in Technical
_Specification Section 6.9.A.6.b.
- 13.. EMF-85-74(P), RODEX2A (BWR) Fuel Rod Thermal-_Mechanical Evaluation Model, Supplement 1 (P)(A) and* Supplement 2 (P)(A), Siemens Power Corporation, February 1998.
- 7.
BASIS FOR THE REVISED REQUIREMENTS The basis for revising the MCPR SL for Dresden Nuclear Power Station Unit 2 is that D2C17 MCPR SL calculations show that a SL of 1.09 is not supportable beyond a cycle exposure of 13,999 MWd/MTU with less than 0.1 % of the rods predicted to experience transition boiling.
Conservatively increasing the MCPR SL to 1.12 for cycle exposures greater than 13,800 MWd/MTU supports Dresden Nuclear Power Station.Unit 2 Cycle 17 operation beyond 13,800 MWd/MTU with fewer than 0.1 % of the rods predicted to experience transition boiling.
The basis for adding Reference 3 to Section 6 of the Technical Specifications is to allow use of the NRC-approved extended burnup limits. The extended burnup limits will support future operation with ATRIUM-98 fuel.
Attachment A Page 4 of 5
ATTACHMENT A DESCRIPTION AND EVALUATION OF PROPOSED CHANGES
- 8.
- APPROVAL AND IMPLEMENTATION SCHEDULE ComEd requests approval of this Technical Specification amendment by May 15, 2000. The requested approval date was conservatively selected to support D2C17 operation beyond a cycle exposure of 13,800 MWd/MTU. Dresden Nuclear Power Station will implement the increased SL prior to reaching 13,800 MWd/MTU cycle exposure.
Attachment A Page 5 of 5