ML100690146
| ML100690146 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 03/05/2010 |
| From: | John Stanley Constellation Energy Nuclear Group, EDF Group |
| To: | Document Control Desk, Office of Nuclear Material Safety and Safeguards, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML100690146 (8) | |
Text
Calvert Cliffs Nuclear Power Plant 1650 Calvert Cliffs Parkway Lusby, Maryland 20657 CENG a joint venture of Constellation *'*eDF Energy' CALVERT CLIFFS NUCLEAR POWER PLANT March 5, 2010 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 Independent Spent Fuel Storage Installation; Docket No. 72-8 Report of Chanzes, Tests, and Experiments - 10 CFR 50.59 and 10 CFR 72.48 In accordance with 10 CFR 50.59(d)(2) and 10 CFR 72.48(d)(2), Calvert Cliffs Nuclear Power Plant, LLC hereby submits a report containing brief descriptions of changes, tests, and experiments approved under the provisions of 10 CFR 50.59 and 10 CFR 72.48.
Attachment (1) of this report includes 10 CFR 50.59 and 10 CFR 72.48 evaluations recorded and approved between January 1, 2009 and December 31, 2009.
Should you have questions regarding this matter, please contact Mr. Douglas E. Lauver at (410) 495-5219.
JJS/RDW/bjd
Attachment:
(1) Calvert Cliffs Nuclear Power Plant Report of Changes, Tests, and Experiments
[10 CFR 50.59(d)(2) and 10 CFR 72.48(d)(2)]
cc: D. V. Pickett, NRC S. Gray, DNR S. J. Collins, NRC M. Weber, NMSS Resident Inspector, NRC
ATTACHMENT (1)
CALVERT CLIFFS NUCLEAR POWER PLANT REPORT OF CHANGES, TESTS, AND EXPERIMENTS
[10 CFR 50.59(d)(2) and 10 CFR 72.48(d)(2)]
Calvert Cliffs Nuclear Power Plant, LLC March 5, 2010
ATTACHMENT (1)
CALVERT CLIFFS NUCLEAR POWER PLANT REPORT OF CHANGES, TESTS, AND EXPERIMENTS
[10 CFR 50.59(d)(2) and 10 CFR 72.48(d)(2)]
Document Id Doc Type Rev Status Revision Date Issued SE00 162 72.48 62 0000 9/2/2009 Subject ANALYSIS TO ALLOW STORAGE OF FUEL ASSEMBLIES WITH SS RODS AND/OR MISSING RODS IN THE ISFSI DSC Summary The purpose of this activity is modifying the design of the NUHOMS-32P system to allow storage of irradiated and unirradiated inert stainless steel rods and/or missing fuel rods. To allow storage of such assemblies new design analyses have been performed to evaluate the effects on the design basis functions.
The presence of vacancies was analyzed to ensure the structural integrity of the fuel assembly and cladding will be maintained during the limiting design basis horizontal cask drop accident. The evaluation performed determined that the vacancy will lead to failure of the horizontal spacer grid ligaments, however the resultant cladding stress was determined to be bounded by the previous analyses and will remain within the stress allowable when no more than two vacancies are allowed in any one column of the fuel assembly. This limitation on vacancies will be controlled by modification of the fuel qualification and selection procedure. This configuration and result ensures the cladding fission product barrier is not challenged, is bounded by previous design analyses and therefore does not result in any undue risk to the health and safety of the public.
To verify the affect on criticality control, the design basis criticality analysis normal and off-normal models were reanalyzed by introducing inert stainless steel rods and vacancies. The new criticality model results demonstrated a decreasing trend in k-effective with the number of inert stainless steel rods and vacancies and all resulting k-effective values were found to be bounded by the existing safety analysis results.
The criticality analyses considered the limitation of no more than two vacancies allowed in any one column and determined no further configuration limitations. Therefore, the proposed activity will have no adverse affect on the criticality control design function of the NUHOMS-32P system.
The proposed activity will introduce storage of activated stainless steel pins. The radiological source term of an assembly with activated stainless steel pins was compared to the design basis gamma assembly source term to ensure the dose rates for the NUHOMS-32P system will not be exceeded. The evaluation determined certain configuration requirements to meet this objective. The results of the evaluation show the dose rates will be maintained provided the number of activated stainless steel pins, their exposure and cooling time and additional host assembly cooling time is specified. These limitations on storage of assemblies with irradiated stainless steel pins will be controlled by modification of the fuel qualification and selection procedure. Also, thermal source of the activated stainless steel pin was analyzed and compared to the existing design basis thermal source. The results show the thermal source of an activated stainless steel pin is much less than the design basis spent fuel rod and will always be bounded by the design basis spent fuel rod for cooling times beyond four years.
In conclusion the proposed activity to store assemblies containing inert stainless steel rods and/or vacancies in the NUHOMS-32P system has been evaluated against all affected design requirements and functions. The evaluations have shown there are no adverse affects on the design bases and the existing design analyses will continue to bound the proposed activity. In support of this conclusion, several new limitations on the configuration of assemblies containing inert stainless steel rods and/or vacancies have been identified and will be incorporated into the procedures for the qualification and selection of fuel assemblies.
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ATTACHMENT (1)
CALVERT CLIFFS NUCLEAR POWER PLANT REPORT OF CHANGES, TESTS, AND EXPERIMENTS
[10 CFR 50.59(d)(2) and 10 CFR 72.48(d)(2)1 Document Id Doc Type Rev Status Revision Date Issued SE00502 50.59 60 0000 9/10/09 Subject UNIT 2 CYCLE 18 CORE RELOAD (2009 RFO)
Summary The proposed activity is the loading and subsequent operation of Calvert Cliffs Unit 2 Cycle 18 (2009 RFO).
Unit 2 Cycle 18 may only operate in plant modes 5, 6, and defueled.
Unit 2 Cycle 18 may not operate in plant modes 1 through 4. The following are the open items that must be addressed prior to requesting approval for modes 1 through 4:
" Various higher mode calculations (TDB, PLHR, LRNI, CEALL, etc). Completion of these calculations is being managed by the U2C18 Project Plan and EN-I-1 10 signoffs.
" Completion of an assessment on the continued applicability of the EQ and other source terms and vessel fluence limits with a 100-assembly batch size, and low enriched 2 wt%/o assemblies. Completion of this assessment is beingtracked by ES200600249-035.
This 10 CFR 50.59 Evaluation, as well as the corresponding ECP, will be revised to permit operation in higher plant modes at a later date after all supporting calculations and analyses have been completed.
Although operation is currently limited to plant modes 5, 6, and defueled conditions, discussions, parameters, and limits applicable to higher modes of plant operation are included herein.
Scope of U2C18 Core Reload (Changes):
- Implementation of Westinghouse Standard Fuel Pellet Specification & miscellaneous
" process improvements
" Zinc Injection
- CECOR Library Mid-Cycle Replacements
" Contingency Core Loading Patterns
" Contingency CEA Replacements
" Contingency for Stainless Steel Pins
" Contingency for Thermally Relaxed Turbo Grid Cage Reason for Activity:
The proposed activity is required to support the biennial refueling of Unit 2 at Calvert Cliffs.
Activity Evaluation:
- The Refueling Boron Concentration will maintain K~ff < 0.95 Ak/k (including a 1% Ak/k conservative allowance for uncertainties).
" The Mode 5 Shutdown Boron Concentration will provide > 3.0 % Ap shutdown margin.
- The fuel handling event remains unchanged.
- Stainless steel pins are used only in approved locations (as necessary) per CENPD-289-P-A.
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ATTACHMENT (1)
CALVERT CLIFFS NUCLEAR POWER PLANT REPORT OF CHANGES, TESTS, AND EXPERIMENTS
[10 CFR 50.59(d)(2) and 10 CFR 72.48(d)(2)]
Document Id Doc Type Rev Status Revision Date Issued SE00502 50.59 60 0000 9/10/09
Conclusions:
- 1. Unit 2 Cycle 18 is only authorized for operation in plant modes 5, 6, and defueled.
- 2. A revision to this 50.59 will be required prior to Unit 2 Cycle 18 entering plant mode 4.
- 3. The currently reported UFSAR accident doses remain bounding for operation of Unit 2 Cycle 18 in plant modes 5, 6, and defueled.
- 4. The proposed activity has been evaluated against the eight criteria of 10 CFR 50.59. It is concluded that no License Amendment is required prior for CCNPP Unit 2 Cycle 18.
Document Id Doc Type Rev Status Revision Date Issued SE00502 50.59 60 0002 3/9/2009 Subject UNIT 2 CYCLE 18 CORE RELOAD (2009 RFO)
Summary The proposed activity is the loading and subsequent operation of Calvert Cliffs Unit 2 Cycle 18 (2009 RFO).
Revision 0000: Authorized Unit 2 Cycle 18 to operate in plant modes 5, 6, and defueled.
Revision 0001: Revision 0001 to SE00502 and the corresponding parent ECP, authorized operation of the redesigned U2C18 core for plant modes 4, 5, and 6. As part of this core redesign, fuel assembly 2W508 was replaced with 1X41 1, assembly 2V01 I was replaced with 2V101, and assembly 2V109 was replaced with 2V103. Multiple CEA's were also substituted in the redesign. Unit 2 Cycle 18 may only operate in plant modes 5, 6, and defueled.
Revision 0002: This revision to SE00502 and the corresponding parent ECP, authorizes operation of the redesigned U2C 18 core in all plant modes.
Scope of U2C18 Core Reload (Not Including Redesign):
- Implementation of Westinghouse Standard Fuel Pellet Specification & miscellaneous
- process improvements
- Zinc Injection
- CECOR LibraryMid-Cycle Replacements
" Contingency Core Loading Patterns
- Contingency CEA Replacements
" Contingency for Stainless Steel Pins
- Contingency for Thermally Relaxed Turbo Grid Cage Scope of U2C18 Core Redesign Efforts:
- Replacement of assembly 2W508 with 1X411 3
ATTACHMENT (1)
CALVERT CLIFFS NUCLEAR POWER PLANT REPORT OF CHANGES, TESTS, AND EXPERIMENTS
[10 CFR 50.59(d)(2) and 10 CFR 72.48(d)(2)]
Document Id Doc Type Rev Status Revision Date Issued SE00502 50.59 60 0002 3/9/2009
" Replacement of assembly 2V01 1 with 2V101
" Replacement of assembly 2V109 with 2V103
" Replacement of CEA-ZC with CEA-ZA (CA06900)
" Replacement of CEA-TI with CEA-NH (CA0690 1)
" Replacement of CEA-5T with CEA-NW (CA0690 1)
Reason for Activity:
The proposed activity is required to support the biennial refueling of Unit 2 at Calvert Cliffs.
Activity Evaluation:
- The Refueling Boron Concentration will maintain Keff < 0.95 Ak/k (including a 1%Ak/k conservative allowance for uncertainties).
" The Mode 5 Shutdown Boron Concentration will provide > 3.0 % Ap shutdown margin.
- The fuel handling event remains unchanged.
- Stainless steel pins are used only in approved locations (as necessary) per CENPD-289-P-A.
Conclusions:
- 1. Unit 2 Cycle 18 is authorized for operation in plant modes.
- 2. The currently reported UFSAR accident doses remain bounding for operation of Unit 2 Cycle 18.
- 3. The proposed activity has been evaluated against the eight criteria of 10 CFR 50.59. It is concluded that no License Amendment is required prior for CCNPP Unit 2 Cycle 18.
Document Id Doc Type Rev Status Revision Date Issued SE00503 50.59 60 0000 2/6/09 Subject BORIC ACID PRECIPITATION/CORE FLUSH EVALUATION FOR CONTAINMENT SUMP BUFFER CHANGEOUT Summary Changing the sump buffer from Trisodium Phosphate (TSP) to Sodium Tetraborate (STB) increases the effective sump post-LOCA boron concentration. The original analysis concluded that boron concentrations will not reach the solubility limit of 32 wt%/o boron before 11 hours1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br /> after the onset of the incident using a total boron amount, decay heat curves and boric acid solubility limits which bound current operating conditions. Therefore, paragraph 4 of UFSAR Section 6.11 is being revised to indicate that the required injection flow must be provided within ... at least 11 hours1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br />..." rather than the"...20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br />..." currently indicated.
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ATTACHMENT (1)
CALVERT CLIFFS NUCLEAR POWER PLANT REPORT OF CHANGES, TESTS, AND EXPERIMENTS
[10 CFR 50.59(d)(2) and 10 CFR 72.48(d)(2)]
Document Id Doc Type Rev Status Revision Date Issued SE00504 50.59 62 0000 3/9/09 Subject EVALUATE DEBRIS (GOTA) TOOL PIN LEFT IN THE RCS DURING THE UNIT 2,2009 RFO Summary The proposed activity "accepts as is" an identified loose part in the reactor vessel or reactor coolant system. The physical characteristics of the loose part have been characterized to be in the range of less than an ounce. The debris is assumed to remain within the reactor vessel or more likely migrate to a number of potential locations including: steam generator inlet (hot leg) bowl or be captured within a steam generator u-tube, or the shutdown cooling suction nozzle on 22 hot leg, the pressurizer surge line on the 21 hot leg, or if the loose part is small enough it could travel through a steam generator U-tube and exit out into a cold leg and either into the reactor vessel bottom or interfacing RCS systems. This evaluations considered the likelihood and consequences of loose part intrusion into any one of these locations and concluded that there are no credible failure mechanisms that exceed the design basis described for accidents and malfunctions in the UFSAR.
Document Id Doc Type Rev Status Revision Date Issued SE00505 72.48 62 0000 8/10/09 Subject EVALUATE A NON-CONFORMANCE WITH A LACK OF FUSION ON TRANSNUCLEAR 32P DSC SPOT WELDS Summary The purpose of this proposed activity is to "accept-as-is" a non-conforming condition resulting from a lack of fusion in spot welds used to join 32P Dry Shielded Canister (DSC) fuel compartment walls to basket plate support bars. During fabrication of the 32P DSCs by Transnuclear's (TN) fabricator, General Electric - Hitachi (GEH) Ionics, GEH discovered a non-conforming condition related to spot fusion welds in the DSC basket. GEH first identified the issue on a similar TN Project (32PTH for Dominion Power - Surry) and initiated an internal corrective action request. Consequently, TN and GEH also determined that the 32P DSCs were also impacted and TN initiated a Level I Corrective Action Report (CAR) 2008-051 which started the 10 CFR Part 21 reporting and evaluation process. Subsequently, TN downgraded Reference 1 to a Level 2 CAR (not reportable) based on a determination that the condition was limited to a small percentage (approximately 1.5% for 32PTH and 2.0% for 32P) of the total population of fusion spot welds for the affected DSCs. This condition did not affect the structural integrity of the basket assembly. The associated non-conformance report, TN NCR 2009-001, Rev. 0 (Form 7, Attachment 1) was initiated to address the affected hardware. Based on the available information on the extent of this condition, it was conservatively assumed that all CCNPP loaded and empty 32P DSCs (stored on-site and at GEH) were affected. CAR 2008-051 provides a discussion of the details and disposition of the 32PTH non-conformance and is the primary technical basis for this proposed activity. DSC units CEG32P-1049 through 1068 have been identified as susceptible to the lack of fusion condition and are not capable of being practically reworked.
Due to the similarity in design of the 32P and 32PTH DSCs (Note: for the specified conditions, the 32PTH is bounding), TN chose to demonstrate by calculation that both DSC designs have sufficient margin to meet acceptance criteria even when a very conservative percent of structural welds (suspect spot welds) are not credited in revised structural and buckling analysis. Because the 32PTH DSC design is more limiting, TN provided a bounding analysis to demonstrate that the non-conformance on the 32P may be accepted-as-is without need for 32P specific reanalysis, rebuild or repair.
In conclusion, The NUHOMS-32PTH basket analysis results bound the NUHOMS-32P basket, therefore all results and conclusions, except fusion welds factor of safety, in the NUHOMS-32PTH calculations can be used for the NUHOMS-32P. All stresses and the 5
ATTACHMENT (1)
CALVERT CLIFFS NUCLEAR POWER PLANT REPORT OF CHANGES, TESTS, AND EXPERIMENTS
[10 CFR 50.59(d)(2) and 10 CFR 72.48(d)(2)]
Document Id Doc Type Rev Status Revision Date Issued SE00505 72.48 62 0000 8/10/09 buckling load limit are within ASME Code allowable limits and the safety factor on the fusion welds is reduced but within the Code allowable limit. Accordingly, all design criteria meet ASME Code allowable stress limits.
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