ML18052A294
| ML18052A294 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 02/20/1986 |
| From: | Buckman F CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | |
| Shared Package | |
| ML18052A293 | List: |
| References | |
| NUDOCS 8602260322 | |
| Download: ML18052A294 (10) | |
Text
ATTACHMENT I Consumers Power Company Palisades Plant Docket 50-255 TECHNICAL SPECIFICATION CHANGE REQUEST SPENT FUEL POOL STORAGE CAPACITY EXPANSION 8602260322-s6o22o- --
~DR ADOCK 05000255 PDR IC1185-0324-NL04 February 20, 1986 9 Pages
CONSUMERS POWER COMPANY Docket 50-255 Request for Change to the Technical Specifications License DPR-20 For the reasons hereinafter set forth, it is requested that the Technical Specifications contained in the Provisional Operating License DPR-20, Docket 50-255, issued to Consumers Power Company on October 16, 1972, for the Palisades Plant be changed as described in Section I below:
I.
Changes The proposed changes to Technical Specification 5.4.2 delineated below are necessary to permit reracking approximately one-half of the Palisades spent fuel pool and the spare (north) tilt pit; and thus, increase the total number of storage locations from 798 to 892.
That increase in the number of storage locations will allow operation, with full core discharge capability, of the Palisades Plant through 1990 and allow Consumers Power Company the time to thoroughly investigate the other rapidly progressing state-of-the-art methods (ie, consolidation, cask storage) of further expanding storage capacity to the level where all spent fuel generated at Palisades before 1998 (the date when a national fuel repository will be established) can be safely stored on the Palisades site.
Proposed changes are identified by a vertical line in the right-hand margin.
The following are brief descriptions of the proposed changes.
Specification 4.2.1 - Reference 7 for Table 4.2.1 has been expanded to include the new Specification 5.4.2f.
Specification 5.4.2b - This section is deleted because no spent fuel storage racks with an 11.25-inch center-to-center distance exist in the Palisades spent fuel pool.
A single rack with 11.25 inch by 10.69 inch center-to-center spacing will be located in the spare (north)* tilt pit.
The other racks which will exist in the spent fuel pool and spare (north) tilt pit have either 10.25 inch (Region I) or 9.17 inch (Region II) center-to-center distances.
Specification 5.4.2c - This section has been expanded to describe the two region spent fuel pool and the existing racks which make up Region I of the spent fuel pool.
Specification 5.4.2d - Describes the Region II racks and the method used to determine which spent fuel can be stored in Region II.
Specification 5.4.2e - Limits the maximum amount of U-235 which can be stored in the spent fuel pool and, therefore, ensures the applicability of the calculations used in the Safety Analysis.
Specification 5.4.2f - Clarifies the requirement that spent fuel pool water boron concentration will be at least 1720 ppm.
TSOP1185-0324-NL02
Palisades Plant 2
Proposed Amendment - Spent Fuel Pool Specification 5.4.2g & h - Changes the alpha character designation.
Specification 5.4.2i - Restricts the storage of spent fuel in Region II racks to that fuel which has the required minimum burnup and assures the fuel enrichment limits assumed in the Safety Analysis will not be exceeded.
II.
Discussion The Nuclear Waste Policy Act of 1982 requires that owners of nuclear power plants diligently pursue licensed alternatives to the use of Federal storage capacity for the storage of the spent fuel expected to be generated by that plant before they enter into a contract with the Federal government to provide such storage. It is in the diligent pursuit of those alternatives that Consumers Power proposes to increase the storage capacity of the* Palisades spent fuel pool.
Removing 376 storage locations having a 10.25 inch center-to-center spacing and replacing them with 470 storage locations having a 9.17 inch center-to-center spacing will permit the Palisades Plant to maintain full core discharge capability for two fuel cycles (ie, Cycle 8 and Cycle 9) longer than previously possible.
In addition, the new storage locations will have more space in each location and permit 2:1 consoli-dation if that method is chosen in the future to further expand storage capacity.
The state-of-the-art, both in fuel consolidation and cask storage, is progressing very rapidly and the ability to wait an addi-tional two to three years before making a commitment to one process should allow Consumers Power Company to select a proven, cost-effective method to further expand the Palisades onsite spent fuel storage capacity.
Reracking approximately one-half of the spent fuel pool and spare (north) tilt pit will divide the spent fuel pool and the spare (north) tilt pit into two regions which are designated Region I and Region II.
(Figure 5.4-1 in Attachment II.)
The reason only approximately one-half of the existing racks are being replaced is due to the need to maintain a portion of the storage capacity with larger center-to-center spacing to accommodate the storage of fuel with little or no burnup.
The existing racks have the required center-to-center spacing to store such fuel.
Region I will contain racks in the spent fuel pool having a 10.25-inch center-to-center spacing and a single rack in the spare (north) tilt pit having 11.25 inch x 10.69 inch center-to-center.spacing.
Region II will contain racks in both the spent* fuel pool and spare (north) tilt pit having 9.17-inch center-to-center spacing. 10Because of the larger center-to-center spacing and the poison (B
) concentration of Region I cells, the only restriction for placement of fuel in Region I is that the initial fuel loading be equal to or less than 41.24 grams of U-235 per axial centimeter.
This assures the fuel enrichment limit assumed in the FSAR Update spent fuel analyses will not be exceeded.
Prior to placement of fuel in Region II cell locations, strict controls are TSOP1185-0324-NL02
Palisades Plant 3
Proposed Amendment - Spent Fuel Pool employed to evaluate burnup of the spent fuel assembly.
Upon determination that the fuel assembly meets the burnup requirements of Table 5.4-1, placement in a Region II cell is authorized.
The addition of Table 5.4-1, Figure 5.4-1, Technical Specifications 5.4.2d and e, and the changes to Technical Specifications 5,4.2c, f and i activate these positive controls and assure the fuel enrichment limits and burnup assumed in the safety analyses will not be exceeded.
Analysis of No Significant Hazards Consideration Consumers Power Company has determined that the activities associated with this change request do not involve a significant hazards considera-tion per 10CFR50.92(c) and, accordingly, a no significant hazards consideration finding is justified.
In support of this determination, necessary background information is first provided, followed by a discussion of each of the significant safety hazards consideration factors with respect to the proposed changes.
Background
The Palisades Plant was designed and constructed with one spent fuel storage pool.
This facility had capacity for 276 spent fuel assemblies.
The Palisades Final Safety Analysis Report addressed the safety implica-tions of these facilities and included relevant parameters associated with criticality, structural integrity, and cooling.
The Palisades Safety Evaluation Report (Docket No 50-255) found the environmental and safety impacts of storage in these facilities to be acceptable.
In 1976, a request to amend the Palisades operating license for in-creased spent fuel storage was submitted.
By letter dated June 30, 1977, the Commission approved Amendment 29 to facility operating license DPR-20 for modification to Palisades Plant spent fuel storage facilities.
The modifications consisted of reracking the spent fuel pool and spare (north) tilt pit with high density fuel storage racks which increased the storage capacity from 276 fuel assemblies to 798 fuel assemblies.
Approval of the amendment included a detailed review and analysis of all relevant storage parameters and potential accidents.
The analyses resulted in a finding that environmental and safety impacts were negligible.
The safety evaluation performed in support of the 1976 request to amend the Palisades operating license to allow reracking of the fuel pool and spare (north) tilt pit to increase the number of storage locations from 276 to 798 addressed the following:
- 1.
Structural and Seismic Analysis
- 2.
Nuclear Criticality Analysis
- 3.
Thermal-Hydraulic Analysis TSOP1185-0324-NL02
Palisades Plant 4
Proposed Amendment - Spent Fuel Pool
- 4.
Accident Analyses
- 5.
Installation Considerations
- 6.
Radiation Exposures
- 7.
Heavy Object Drop Evaluation In that June 30 1977 Safety Evaluation it was determined that the proposed modifications to the Palisades spent fuel pool would be accept-able because:
(1) the rack structural design would withstand conditions during normal operation combined with the maximum safe shutdown earth-quake (SSE), (2) the rack design would preclude criticality for any moderating condition, (3) the existing spent fuel cooling system would adequately cool the increased heat load, (4) the increased radiation doses, both onsite and offsite would be negligible, and (5) spent fuel cask handling operations would not be permitted until the NRC had reviewed and approved the previously submitted (Augusf 9, 1974) Spent Fuel Cask Drop Analysis.
The current spent fuel storage capacity.at Palisades consists of 798 storage locations in the spent fuel pool and spare tilt pit.
With this application, Consumers Power Company is requesting approval to rerack the Palisades spent fuel storage facilities to increase the storage capacity as set forth in the attached Safety Analysis Report.
Evaluation The following evaluation demonstrates (by reference to the analysis contained in the attached Safety Analysis Report) that the proposed changes would not meet any of the three significant hazards considera-tion standards.
The analyses for the proposed reracking are accom-plished using currently accepted codes and standards as specified in Section 4.2 of the attached Safety Analysis Report.
(1)
Involve a significant increase in the probability or consequences of an accident previously evaluated.
In the course of the analysis, Consumers Power Company has identified the following potential accident scenarios:
- 1.
A spent fuel assembly drop in the spent fuel pool.
- 2.
Loss of spent fuel pool cooling system flow.
- 3.
A seismic event.
- 4.
A spent fuel cask drop
- 5.
An installation accident.
TSOP1185-0324-NL02
Palisades Plant Proposed Amendment - Spent Fuel Pool The probability of any of the first four accidents is not affected by the racks themselves; thus reracking cannot increase the probability of these accidents.
As for an installation accident, Consumers Power Company does not intend to carry any rack directly over the existing stored spent fuel ~ssemblies. All work in the spent fuel pool area will be controlled and performed in strict compliance with specific written procedures.
The Spent Fuel Pool Building crane which will be used to access the spent fuel pool area has been addressed in Consumers Power Company's response to the NUREG-0612, "Control of Heavy Loads at Nuclear Power. Plants."
This response demonstrated Palisades Plant's compliance with 5
Phase I of the NUREG 0612 criteria.
In addition, any temporary construction cranes which will be used to move racks within the spent fuel pool will meet the design and operational requirements of Section 5.1.1 of NUREG-0612.
By letter dated November 9, 1983, the NRG concluded that* the control of heavy loads program (Phase 1) at the Palisades Plant is in compliance with the requirements of NUREG-0612.
This program provides for the safe handling of heavy loads in the vicinity of the Spent Fuel Pool.
Accordingly, the installation of the new racks will not involve a significant increase in the probability of an accident previously evaluated.
The consequences of (1) a spent fuel assembly drop in the spent fuel pool are discussed in the attached Safety Analysis Report.
For this accident condition, the criticality acceptance criterion is not violated.
The radiological consequences of a fuel assembly drop are not changed from that described in Chapter 14 of the Palisades FSAR Update.
The NRC also conducted an evaluation (as described in the Palisades SER dated June 30, 1977) of the poten-tial consequences of a fuel handling accident and found the calcu-lated doses to be less than 10CFRlOO requirements.
Thus,.the consequences of this type accident will not be increased from previously evaluated spent fuel assembly drops, and have been found acceptable by the NRG.
The consequences of (2) loss of spent fuel pool cooling system flow, are evaluated and are described in Section 3.0 of the Safety Analysis Report (Attachment III).
As indicated in Section 3.0, there is sufficient time to provide an alternate means for cooling (ie, the fire water system or the shutdown cooling system) in the event of a failure in the cooling system.
Thus, the consequences of this type accident will not be significantly increased from previously evaluated loss of cooling system flow accidents.
The consequences of (3) a seismic event, are evaluated and are described in Section 4.0 of the attached Safety Analysis Report.
The new racks are designed and fabricated to meet the requirements of applicable portions of the NRG Regulatory Guides and published standards listed in Section 4.2 of the Safety Analysis Report.
The method of support for the free standing new racks is different than that used to support the existing racks which rest on the fuel pool TSOP1185-0324-NL02
Palisades Plant 6
Proposed Amendment - Spent Fuel Pool floor in a similar manner to the new racks but are limited in horizontal movement by adjacent racks and the fuel pool walls.
The existing racks continue to be restricted in horizontal movement in the east, south and west directions by adjacent racks and the fuel pool walls.
Analysis will be comple~ed which shows:
(1)
No horizontal support is required to prevent northerly move-ment of the Region I racks; or, (2)
Additional modification is required to prevent the Region I racks from moving towards the north.
If modifications are required to limit horizontal movement of the Region I racks in the northerly direction and to maintain the existing margin of safety, those modifications will be completed either before the installation of new racks, or, as permitted by existing Technical Specifications, fuel stored in the racks adjacent to the new racks (Region II) will have decayed for a minimum of twelve months.
The new racks (Region II) are designed so that the floor loading from the racks filled with spent fuel assemblies does no~ exceed the structural capacity of the Spent Fuel Building.
The Spent Fuel Building and pool and tilt pit structure have been designed in accordance with the criteria outlined in Section 5 of the Palisades FSAR Update and previously accepted by the NRC.
Thus, the conse-quences of a seismic event will not increase from previously evaluated events.
The consequences of (4) a heavy object drop have previously been evaluated and described in the November.1, 1976 submittal requesting Amendment 29 to the Palisades license.
The June 30, 1977 SER supporting that Amendment 29 requested that spent fuel cask movement into the spent fuel pool building be prohibited until the cask drop analysis contained in the August 9, 1974 submittal is evaluated.
Section 5.4.2 of the Palisades Plant Technical Specifications prevents the movement of a spent fuel cask into the spent fuel pool building and that restriction will remain effective after the installation of the new racks.
Therefore, until the November 1, 1976 Heavy Object Drop Analysis evaluation or the August 9, 1974 Spent Fuel Drop Analysis evaluation is completed by the NRC staff, no spent fuel cask is allowed into the spent fuel pool building and there is no possibility of a spent fuel cask being dropped on the spent fuel stored in the spent fuel pool or spare (north) tilt pit.
Heavy objects are not allowed over the spent fuel pool proper by administrative control; but are allowed over the spare (north) tilt pit after the fuel stored in the spare (north) tilt pit has decayed a specified minimum time.
New racks will be installed in a portion of the spare (north) tilt pit to increase its storage capacity from 110 assemblies to 128 assem-blies.
Analysis shows the increased storage capacity will not TSOP1185-0324-NL02
Palisades Plant 7
Proposed Amendment -
Spent Fuel Pool (2) affect the postulated consequences of a heavy object drop into the spare (north) tilt pit by an amount which will cause 25 percent of the limits of 10CFRlOO to be exceeded.
Therefore, the consequences of a heavy load drop, will not be significantly increased from previously evaluated accident analys~s. Thus, it is concluded that the proposed change to rerack the spent fuel pool and spare (north) tilt pit does not involve a significant increase in the probability or consequences of an accident previously evaluated.
Create the possibility of a new or different kind of accident from any accident previously evaluated.
Consumers Power Company has evaluated the proposed reracking in accordance with the guidance of the NRC position paper entitled, "OT Position for Review and Acceptance of Spent Fuel Storage and Handling Applications," appropriate NRC Regulatory Guides, appropriate NRC Standard Review Plans, and appropriate Industry Codes and Standards as listed in Section 4.2 of the attached Safety Analysis Reports.
In addition, Consumers Power Company has reviewed several previous NRC Safety Evaluation Reports for rerack applications similar to our proposal.
As a result of this review of those Evaluation Reports and the attached Safety Analysis, Consumers Power Company finds that the installation and use of the new racks, as well as the use of the existing racks which remain as Region I does not create the possibility of a new or different kind of accident from any accident previously evaluated for Spent Fuel Storage Facilities.
The current FSAR does not include analysis of misloading spent fuel in the proposed Spent Fuel Pool Region II racks.
(3)
Involve a significant reduction in a margin of safety.
The NRC Staff Safety Evaluation review process has established that the issue of margin of safety, when applied to a reracking modifi-cation, needs to address the following areas:
- 1.
Nuclear criticality considerations
- 2.
Thermal-Hydraulic considerations
- 3.
Mechanical, material and structural considerations The established acceptance criteria for criticality is that the neutron multiplication factor in spent fuel pools shall be less than or equal to 0.95, including all uncertainties, under all conditions.
As discussed in Section 3.0 of the attached Safety Analysis Report, this margin of safety is satisfied by the new rack design.
The methods to be used in the criticality analysis conform with the applicable portions of the codes, standards, and specifications listed in Section 4.2 of the Safety Analysis Report.
In meeting the acceptance criteria for criticality in the spent fuel pool, TSOP1185-0324-NL02
Palisades Plant 8
Proposed Amendment - Spent Fuel Pool such that K f is always less than 0.95, including uncertainties at a 95/95 proEatility confidence level, the proposed reracking of the spent fuel pool and spare tilt pit does not involve a significant reduction in the margin of safety for nuclear criticality.
Conservative methods are used to calculate the maximum fuel temper-ature and the increase in the temperature of the water in the spent fuel pool.
The thermal-hydraulic evaluation uses the methods described in Section 3.0 of the Safety Analysis Report to demon-strate that the fuel temperature margin of safety is maintained.
The proposed reracking results in an increase of the heat load to the spent fuel pool cooling system.
The evaluation in Section 3.0 of the Safety Analysis Report shows that the existing spent fuel cooling system maintains the pool temperature margins of safety for the calculated increase in heat load.
Thus, there is no signifi-cant reduction in the margin of safety for thermal-hydraulic or spent fuel cooling concern.
The main safety function of the spent fuel pool and the racks is to maintain the spent fuel assemblies in a safe configuration through all normal and abnormal loadings, such as an earthquake, impact due to a spent fuel cask drop, drop of a spent fuel assembly, or drop of any other heavy object.
The mechanical, material, and struc-tural considerations of the proposed racks are described in Section 4.0 of the attached Safety Analysis Report.
As also described in Section 4.0 of the Safety Analysis Report, the proposed racks are to be designed in accordance with applicable portions of the "NRC Position for Review and Acceptance of Spent Fuel Storage and Handling Applications," dated April 14, 1978, as modified January 18, 1979; Standard Review plan 3.8.4; and Section 5 of the Palisades FSAR Update.
The rack materials used are compatible with the spent fuel pool and the spent fuel assemblies.
The structural considera~ions of the new racks address margins of safety against tilting and deflection or movement, such that the new racks do not impact each other or the pool walls, damage spent fuel assemblies,*
or cause criticality concerns.
Thus, the margins of safety are not significantly reduced by the proposed rerack.
In summation, it has been shown that the proposed spent fuel storage facility modifications do not:
- 1.
Involve a significant increase in.the probability or consequences of an accident previously evaluated; or
- 2.
Create the possibility of a new or different kind of accident from any accident previously evaluated; or
- 3.
Involve a significant reduction in a margin of safety.
Therefore, Consumers Power Company has determined that the proposed installation and use of new spent fuel racks does not involve a signifi-cant safety hazard.
TSOP1185-0324-NL02
Palisades Plant 9
Proposed Amendment - Spent Fuel Pool III.
Conclusion The Palisades Plant Review Committee has reviewed this Technical Specification Change Request and has determined that this change does involve an unreviewed safety question, but has been determined to involve no significant hazards consideration.
This change has also been reviewed under the cognizance of the Nuclear Safety Board.
A copy pf this Technical Specification Change Request has been sent to the State of Michigan official designated to receive such Amendments to the Operating License.
CONSUMERS POWER COMPANY Buckman, Vice President Nuclear Operations Sworn and subscribed to before me this 20th day of February 1986.
~l~.~
Elaine E Buehrer, Notary Public Jackson County, Michigan My commission expires October 31, 1989 TSOP1185-0324-NL02