ML17191B239
| ML17191B239 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 02/16/1999 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML17191B241 | List: |
| References | |
| NUDOCS 9902190335 | |
| Download: ML17191B239 (4) | |
Text
I UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555--0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 171 TO FACILITY OPERATING LICENSE NO. DPR-19 AND AMENDMENT NO. 166 TO FACILITY OPERATING LICENSE NO. DPR-25 COMMONWEAL TH EDISON COMPANY DRESDEN NUCLEAR POWER STATION. UNITS 2 AND 3 DOCKET NOS. 50-237 AND 50-249
1.0 INTRODUCTION
By letter dated August 14, 1998 (Reference 1) Commonwealth Edison Company (ComEd, the licensee) requested changes to the Technical Specifications (TS) for Dresden Nuclear Power Station, Units 2 and 3. Additional information was submitted by letters dated October 13, 1998 (Reference 2) and December 23, 1998 (Reference 3). The December 23, 1998, submittal provided additional Clarifying information that did not change the initial proposed no significant hazards consideration determination. The proposed changes are due to the transition to Siemens Power Corporation (SPC) ATRIUM-98 fuel. The key items are:
- 1.
Incorporation of SPC's new methodology that will enhance operational flexibility and reduce the likelihood of future plant derates,
- 2.
administrative changes that both eliminate the cycle specific implementation of.
ATRIUM-98 fuel and adopt Improved Technical Specification language where appropriate, and
- 3.
changes to the Dresden Minimum Critical Power Ratio (MCPR) safety limits.
2.0 EVALUATION The requested TS changes can be categorized into four different topics:
- 1.
Addition of SPC Topical for ATRIUM-98 fuel -ANF-1125(P)(A) Supplement 1, Appendix E (Reference 4);
- 2.
. change to MCPR safety limit;
- 3.
removal of footnotes limiting operation with ATRIUM-98 Fuel reloads; and
- 4.
revision to the thermal limit descriptions.
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- Currently Dresden, Units 2 and 3, are completing the transition from General Electric (GE) to SPC fuel, including the use of associated methodologies. The SPC Topical for ATRIUM-98.
fuel (ANF-1125(P)(A), Supplement 1, Appendix E) was recently reviewed and approved by NRC (Reference 4). The NRC approval of this topical listed three conditions to which ComEd has committed (Reference 3). Thus, the SPC Topical for ATRIUM-98 fuel (ANF-1125(P)(A),
Supplement 1, Appendix E) is acceptable for use for Dresden, Units 2 and 3. The addition of this methodology will ensure that values for cycle specific parameters are determined such that all applicable limits of the safety analysis are met.
The change to MCPR safety limit was due to the change to SPC fuel. Using the S.C. AFB critical power correlation methodology and the ATRIUM-98 additive constant uncertainty resulting from the approval of Appendix E (Reference 4), the MCPR safety limit for Dresden, Unit 3, will be 1.10. The MCPR safety limit for Dresden, Unit 2, will remain 1.09. The applicability of the MCPR safety limit will be confirmed on a cycle-by-cycle basis. These values are anticipated to bound the actual MCPR safety limit for future Dresden SPC reloads. Since the MCPR safety limits were calculated with an approved methodology, and used the approved additive constant uncertainty from Appendix E, the change to this value will ensure that 99.9 percent of the fuel rods will avoid transition boiling during normal operation and anticipated operational occurrences and is acceptable.
The removal of the footnote limiting operation with ATRIUM-98 fuel to specific reloads is due to the fact the footnote is no longer needed since the methodology for ATRIUM-98 fuel has been approved. Thus, this change is aceeptable.
The change to revise the thermal limit descriptions is to generalize the definition of the average planar linear heat generation rate (APLHGR) limit to allow either a bundle average or an average planar exposure based APLHGR limit, consistent with the loss-of-coolant accident (LOCA) analysis of record. Currently the Dresden TSs specify the APLHGR limit as a function of the average planar exposure. However, the results of S.C.'s NRC-approved LOCA methodology may be applied on either a bundle average or average planar exposure. Thus, a less stringent description of APLHGR is proposed by this amendment such that the detailed information to which the APLGHR is monitored is specified in the core operating limits report (COLR). This generalization of the definition of APLHGR is consistent with the Improved Standard Technical Specifications (NUREG 1433/1434, Revision 1) wording. Both maximum aver~ge planar linear heat generation rates (MAPLHGR) (bundle average exposure based and planar average exposure based) are acceptable for Appendix K of 10 CFR Part 50. Thus, this change is acceptable.
3.0 TECHNICAL SPECIFICATION CHANGES Technical Specifications -Table of Contents - Delete item for definition of Average Planar Exposure and delete definition of Average Planar Exposure. This is aeceptable because the average planar exposure is no longer used.
Technical Specification 2.1. B - Change the MCPR to 1.10 for Unit 3. This change results from the use of ATRIUM 98 fuel, will ensure that less than 0.1 percent of the fuel rods in the core undergo transition boiling and is, therefore, acceptable.
- Technical Specification 3/4.11A and 3/4.11 D - The description of the APLHGR limiting condition of operation (LCO) is changed to not specify that the APLHGR should be a function of average planar exposure and the description of the linear heat generation rate (LHGR) is changed to not specify that the LHGR should be a function of average planar exposure.
These changes are acceptable because the APLHGR and LHGR are based on the bundle average exposure consistent with the LOCA analysis.
Technical Specification 5.3-Removal of the Dresden, Unit 3, Cycle 15, and Dresden, Unit 2, Cycle 16, specific footnote. This change is acceptable because the cycle specific footnote is no longer needed, since the methodology described in the topical has been approved.
. Technical Specification 6.9.A.6.b -Addition of the S.C. topical report, ANF-1125, Supplement 1,.
Appendix E, for the ATRIUM-98 additive constant uncertainties. This change is needed for use of the ATRIUM-98 fuel and addition of this methodology will ensure that values for cycle-specific parameters are determined such that all applicable limits of the safety analysis are met.
4.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Illinois State official was notified of the proposed issuance of the amendments. The State official had no comments.
5.0 ENVIRONMENTAL CONSIDERATION
The amendments change a requirement with respect to the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendments involve no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendments involve no significant hazards consideration, and there has been no public comment on such finding (63 FR 59588). The amendments also change recordkeeping or reporting requirements.
Accordingly, the amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9) and (c) (10). Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendments.
6.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and !)afety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendments will not be inimical to the common defense and security or to the health and safety of the public.
Principle Contributor: M. Chatterton Date: February 16, 1999
7.0 REFERENCES
- 1.
Letter from RM. Krich, Commonwealth Edison Company to NRC, dated August 14, 1998.
- 2.
- Letter from RM. Krich, Commonwealth Edison Company to NRC, dated October 13, 1998.
- 3.
Letter from RM. Krich, Commonwealth Edison Company to NRC, dated December 23, 1998.
- 4.
ANF-1125(P), Supplement 1, Appendix E, "AFB Critical Power Correlation Determination of ATRIUM-98 Additive Constant Uncertainties.ft and NRC SER, "Acceptance for Referencing of Licensing Topical Report ANF-1125(P), Supplement 1, Appendix E, Critical Power Correlation Determination of ATRIUM-98 Additive Constant Uncertainties.ft T.H. Essig to H.D. Curet, September 23, 1998.