ML050340036
| ML050340036 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 01/31/2005 |
| From: | Nietmann K Constellation Energy Group |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML050340036 (8) | |
Text
Kevin J. Nietmann 1650 Calvert Cliffs Parkway Plant General Manager Lusby, Maryland 20657 410.495.4101 410.495.4787 Fax Constellation Energy Calvert Cliffs Nuclear Power Plant January 31, 2005 U. S. Nuclear Regulatory Commission Washington, DC 20555 ATTENTION: Document Control Desk
SUBJECT:
Calvert Cliffs Nuclear Power Plant Unit Nos. I & 2; Docket Nos. 50-317 & 50-318 Response to Request for Additional Information Concerning the License Amendment Request to Incorporate Methodology References for the Implementation of PHOENIX-P, ANC, PARAGON, and Zirconium Diboride into the Technical Specifications This letter provides the information requested in Reference (a). This information supports and/or clarifies the information provided in Reference (b). This information does not affect the No Significant Hazards Consideration Determination or the Environmental Impact Review of Reference (b). This letter supercedes our letter dated January 3, 2005, with the same subject.
Requested Information:
- 1. In Attachment 3 to the July 15, 2004, letter, which provides supplemental information to dlenonstrate the applicability of the Westinghouse nuclearphysics cotle package to Calvert Cliffs, Table 2.2-3 provides comparisons between the measurements and predictions 0ising the PHOENIX-P/ANC codles) of the Calvert Cliffs Unit 2 Cycles 13 and 14 control rod worth. These comparisons show that the differences are as high as -6.9% and 7% for CEA [control element assemblyl groups 2 and 5, respectively.
Providejustification for using thte Westinghouse nuclear physics package to Calvert Cliffs in light of these largedifferences.
CCNPP Response:
Table 2.2-3 of Attachment 3 to the July 15, 2004, letter provides a comparison of the predictions of the Westinghouse nuclear physics code package (PHOENIX-P/ANC) to Calvert Cliffs 2 Cycles 13 and 14 measured control rod worth. The comparison of total measured control rod worth showvs very good agreement between measured and predicted at 0.4% and -2.2% for Cycles 13 and 14, respectively. This indicates very good prediction of total scram worth.
The table also shows that the differences between measured worths of individual CEA groups and PHOENIX-P/ANC predictions range from -6.9% to 7%. This is within the CEA Group uncertainty
Document Control Desk January 31, 2005 Page 2 of +10% used in the current Nuclear Regulatory Commission (NRC) approved design methods, as reported in CENPD-266-P-A, "The ROCS and DIT Computer Codes for Nuclear Design."
The differences between the measured and predicted values in the CEA worths are incorporated into the uncertainties. The uncertainties are conservatively applied in the safety analysis methodology.
- 2. The NRC has approved WCAP-16072-P-A, "Implementation of Zirconium Diboride Burnable Absorber in CE /Combustion Engineering] Nuclear Power Fuel Assembly Designs," with condlitiots and limitations specified in Section 4.0 of the Safety Evaluation Report. In referencing TWCAP-16072-P-A for the use of Zirconium Diboride (ZrB2 ) in the Calvert Cliffs integralfuel burnable absorber design, the licensee states (in Section 4 of Attachment 1 to the July 15, 2004, letter) that Calvert Cliffs agrees to all conditions and limitations in the Safety Evaluation Report
[SERJ that approved the Zirconium Diboride Topical. The licensee also states that Culvert Cliffs will update staff training and proceduresfor the operating strategy that may result in the peak positive AITCMonderator temperaturecoefflcientq occurringafter the beginning of thefuel cycle.
Pleaseprovide a regulatorycomntitnten for the conditions and limitationsspecified in the SER oht WCAP-16072, including actions committed by Calvert Cliffs, the types of actions (either one-time action or continuing compliance) and scheduledcompletion dates if required.
CCNPP Response:
Each condition and limitation specified in the SER, each action committed to by Calvert Cliffs Nuclear Power Plant (CCNPP), the types of action, and currently scheduled completion date is listed in the table below:
Conditions and Limitations from Acinb avr lfsType of Scheduled WCAP-16072-P-A SER Action Completion
- 1. A license amendment is required Calvert Cliffs Nuclear Power One time Completed to add this Topical Report to the Plant requested a license action Core Operating Limits Report amendment to add this Topical analytical methods listed in the Report to the Core Operating licensee's Technical Limits Report analytical Specifications. methods listed in the Technical Specifications. The request was submitted in Reference (b).
- 2. Plant-specific core design Cycle specific evaluations will Continuing guidelines or cycle-specific be performed as part of the Compliance calculations shall be used to reload efforts to verify that verify that required power required power margins in the margins in the axial cutback axial cutback regions are regions are maintained within maintained within the safety safety analysis limitations. analysis limitations.
Document Control Desk January 31, 2005 Page 3 Conditions and Limitations from Action by Calvert Cliffs Type of l Scheduled WCAP-16072-P-A SER I__Action__byCalvert __CHAction Completion 3.Plant Technical Specification The CCNPP Technical Continuing Surveillance Requirements (SRs) Specification requires an MTC Compliance on MTC validate the physics measurement with each fuel predictions and ensure that plant cycle within seven effective full operations remain within power days of initially reaching allowable limits. In addition to an equilibrium condition of current SRs, licensees shall > 90% rated thermal power.
confirm that the peak positive hot After that MTC measurement, full power (HFP) MTC is within CCNPP will confirm that the the Technical Specification limits peak positive HFP MTC is at the highest Reactor Coolant within the Technical System (RCS) soluble boron Specification limits at the concentration predicted during highest RCS soluble boron full power operation. The peak concentration expected during positive HFP MTC shall be full power operation for the fuel derived by adjusting the cycle. The peak positive full measured MTC at HFP power MTC shall be derived by beginning-of-cycle (BOC) adjusting the measured MTC at conditions to the maximum HFP full power conditions to the soluble boron concentration maximum full power soluble expected during the cycle. boron concentration expected A direct measurement of MTC is during the cycle.
required at the highest RCS soluble boron concentration predicted during full power operation. This direct measurement is only required for the first application of ZrB2 integral fuel burnable absorber (IFBA) in a CE 14x14 or 16x16 fuel assembly design. During the first cycle implementation,
Document Control Desk January 31, 2005 Page 4 Conditions and Limitations from Action by Calvert Cliffs Typeiof Scheduled WCA-107-PA ERAction Completion_
Westinghouse shall provide the No action required by Calvert staff with a letter containing the Cliffs. As stated in the SER and following information: Reference (d), Westinghouse
- i. Measured HFP BOC MTC shall provide the staff with a (Technical Specification SR), letter containing the items i ii. Measured HFP MTC at through iv. Also, see response to highest RCS soluble boron Question 3 below.
concentration, iii. Calculated HFP MTC at highest RCS soluble boron concentration, and iv. Demonstrated accuracy of the calculated HFP MTC within current analytical uncertainties.
In addition, plant procedures used Calvert Cliffs will update the One time Unit 2 to perform MTC surveillances procedures used to perform action procedures are shall be updated, where MTC surveillances. This update scheduled to be appropriate, to reflect the will reflect the requirement to updated prior calculated peak positive HFP verify the peak positive full to February 21, MTC along with ZrB2 IFBA's power MTC. 2005. Unit I distinctive trend in RCS critical procedures to boron concentration. be updated prior to February 1, 2006.
- 4. Prior to startup following a In the event of a Condition III or NA NA Condition III or IV event, IV event at Calvert Cliffs, an licensees must evaluate clad evaluation of fuel structural hydriding to ensure that hydrides integrity with respect to radial have not precipitated in the radial hydriding will be performed direction. prior to power ascension.
Document Control Desk January 31, 2005 Page 5 Conditions and Limitations from
- I Typeof Scheduled WCAP-16072-P-A SER Acton y Calvert Cli SAction Completion S. CEN-372-P-A constraints and The constraints and limitations Continuing limitations with regard to rod of CEN-3 72-P-A will continue Compliance internal pressure and departure to be met. Analysis performed from nucleate boiling propagation for the implementation of ZrB 2 must continue to be met. In IFBA at Calvert Cliffs has addition, licensees must ensure demonstrated that cladding that the following two conditions bursts are precluded for are satisfied: Condition I, II, III, and IV
- a. For Condition I (normal), events.
Condition II (moderate frequency), and Condition III (infrequent) events, fuel cladding burst must be precluded for ZrB2 IFBA fuel rods. Using models and methods approved for CE fuel designs, licensees must demonstrate that the total calculated stress remains below cladding burst stress at the cladding temperatures experienced during any potential Condition II or Condition III event. Within the confines of the plant's licensing basis, licensees must evaluate all Condition II events in combination with any credible, single active failure to ensure that fuel rod burst is precluded.
- b. For Condition IV non-loss-of-coolant accident events which predict clad burst, the potential impacts of fuel rod ballooning and bursting need to be specifically addressed with regard to coolable geometry, RCS pressure, and radiological source term.
- 3. Section 4 of Attachment 1 states that "Calvert Cliffs will confirm that the peak positive hot full power MTC is within the TS limits at the highest RCS soluble boron concentrationpredicted during full power operation. The peak positive HFP MTC will be determined by adjusting thle HFP MTC measured at beginning of cycle to the maximum HFP soluble boron concentration expected during the fuel cycle." However, Condition 3 in the staff's safer' evaluation for WVCAP-16072-P-A states thiat "in order to ensure a conservative adjustmnent, a direct measurement of AITC is required at the highest RCS soluble boron concentrationpredicted during full power
Document Control Desk January 31, 2005 Page 6 operation. This direct mneasturenment is only requiredfor the first application of ZrB2 IFBA in a Combustion Engineering14x14 or 16x1 6fuel assembly design."
Since Calvert Cliffs may be theefirst application ofZrB2 IFBA in a CE 14x14fuel assembly design, the licensee's regulatory commitment needs to include that a direct measiurenment of MTC at the peak soluble boron concentrationOvill be performed.
CCNPP Response:
Current best estimate predictions for Calvert Cliffs Unit 2 Cycle 16 show that the cycle maximum, full power, RCS boron concentration will exceed the beginning of cycle value by only 4 ppm. The difference in MTC associated with these two boron levels is negligible. Any difference between the measured MTC at the beginning of cycle and at the time of maximum RCS boron concentration would be dominated by the measurement uncertainty. This would not validate the confirmation method.
The commitment in the SER will be satisfied during Cycle 18 of Arkansas One Unit 2 as described in Reference (c). ANO-2 is also a CE plant implementing Zirconium Diboride IFBA. ANO-2 Cycle 18 is scheduled to commence operation at essentially the same time as Calvert Cliffs Unit 2 Cycle 16.
The difference between BOC and cycle maximum RCS boron concentration is much larger (about 180 ppm) for ANO-2 Cycle 18. The difference between the MTC measured at BOC and the MTC measured at peak RCS boron concentration will be more significant and can be used in evaluating the peak MTC confirmation method. Also, documented in Reference (d), Westinghouse committed to supply the NRC the measurement data from ANO-2 for the first application of ZrB2 IFBA in a CE fuel assembly design.
If the MTC measurement at peak RCS boron concentration for ANO-2 Cycle 18 should show that the MTC confirmation method needs to be adjusted with additional conservatisms, then Calvert Cliffs will apply additional conservatisms when confirming the MTC at the maximum HFP soluble boron concentration expected during the fuel cycle.
Document Control Desk January 31, 2005 Page 7 Should you have questions regarding this matter, we will be pleased to discuss them with you.
Very truly yours, STATE OF MARYLAND
- TO WIT:
COUNTY OF CALVERT 1, Kevin J. Nietmann, being duly sworn, state that I am Plant General Manager - Calvert Cliffs Nuclear Power Plant, Inc. (CCNPP), and that I am duly authorized to execute and file this License Amendment Request on behalf of CCNPP. To the best of my knowledge and belief, the statements contained in this document are true and correct. To the extent that these statements are not based on my personal knowledge, they are based upon information provided by other CCNPP employees and/or consultants.
Such information has been reviewed in accordance with company practice and I believe it to be reliable.
Subscribed and sworn before me, aN~ptary Public in and for the State of Maryland and County of (ai I v r ,this ,L day of B ury 2005.
WITNESS my Hand and Notarial Seal: (AI"nq, awzxo-/-
Notary Public Mmop ='-
My Commission Expires: -. A y-/5 -¢(0 Date KJN/DJM/bjd
Document Control Desk January 31, 2005 Page 8
REFERENCES:
(a) Letter from Mr. R. V. Guzman (NRC) to Mr. G. Vanderheyden (CCNPP), dated December 14, 2004, "Calvert Cliffs Nuclear Power Plant, Unit Nos. I and 2 (CCNPP 1 and 2) - Request for Additional Information RE: Incorporating Core Operating Limits Analytical Methodology References into Technical Specifications (TAC Nos. MC4019 and MC4020)"
(b) Letter from Mr. B. S. Montgomery (CCNPP) to Document Control Desk (NRC), dated July 15, 2004, "License Amendment Request: Incorporate Methodology References for the Implementation of PHOENIX-P, ANC, PARAGON, and Zirconium Diboride into the Technical Specifications" (c) Letter from J. S. Forbes (Entergy) to U.S. Nuclear Regulatory Commission, dated July 8, 2004, "License Amendment Request to Support Cycle 18 Core Reload Arkansas Nuclear One, Unit 2 III 2CAN070402" (d) Letter from J. A. Gresham (Westinghouse Electric Company) to U.S. Nuclear Regulatory Commission, dated September 8, 2004, "Westinghouse's Response to Item 3 of Section 4.0 (CONDITIONS AND LIMITATIONS) of the Final Safety Evaluation for topical report WCAP-16072-P-A, Revision 0, 'Implementation of Zirconium Diboride Burnable Absorber Coatings in CE Nuclear Power Fuel Assembly Designs' "
cc: S. L. Miller, Esquire S. J. Collins, NRC J. E. Silberg, Esquire Resident Inspector, NRC R. V. Guzman, NRC R. I. McLean, DNR