ML18052A744
| ML18052A744 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 10/16/1986 |
| From: | Dewitt R CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | |
| Shared Package | |
| ML18052A743 | List: |
| References | |
| NUDOCS 8610270105 | |
| Download: ML18052A744 (10) | |
Text
!' 1
- 8610270105 PDR ADOCK p
ATTACHMENT I Consumers Power Company Palisades Plant Docket 50-255 TECHNICAL SPECIFICATION CHANGE REQUEST SPENT FUEL POOL STORAGE CAPACITY EXPANSION 861016 0500025'5 PDR October 16~ 1986 9 Pages IC0886-0129-NL04
CONSUMERS POWER COMPANY Docket 50-255 Request for Change to the Technical Specifications License DPR-20 Revision.1 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 approxima*tely 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 to the Technical Specifications 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-lnch 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~
TSOP1185-0324-NL04 Rev 1
Palisades Plant Proposed Amendment - Spent Fuel Pool Specification 5.4.2f*-
Clari~ies the requirement that spent fuel pool water boron concentration will be at least 1720 ppm.
Specification 5.4.2g & h - Changes the alpha character designation.
2 Specification 5.4.2i - Restricts the storage of spent fuel in Region II racks to that fuel which h~s 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 TSOP1185-0324-NL04 Rev 1
1--
- Palisades Plant 3
Proposed Amendment - Spent Fuel Pool cells, the only restriction for placement of fuel in Region I is that the.initial fuel loading be equal to or less than 3.27 w/o of U-235.
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 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 consideration per 10CFR50.92(c) and, accordingly, a no significant hazards consideration finding is justified.
In support of this determination, necessary backg.round 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 implications 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 increased spent fuel storage was submitt"ed.
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
- TSOP1185~0324-NL04 Rev 1
I -
J Palisades Plant 4
Proposed Amendment - Spent Fuel Pool 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 Criticali~y Analysis
- 3.
Thermal-Hydraulic Analysis
- 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 modi.fications to the Palisades spent fuel pool would be accept able because:
(1) the rack structural design would withstand conditions dur1ng normal operation combined with the maximum safe shutdown earthquake (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 (August 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 consideration st~ndards. The analyses for the proposed reracking were accomplished using currently accepted codes and standards as specified in Section 4'.2 of the attached Safety Analysis Report.
TSOP1185-0324-NL04 Rev 1
f -
Palisades Plant 5
Proposed Amendment - Spent Fuel Pool (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.
The probability of any of the first four accide~ts 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 assemblies.
All work in the spent fuel pooi 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 Ueavy Loads at Nuclear Power Plants."
This response* demonstrated Palisades Plant's compliance with 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 NRC 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 potential consequences. of a fuel handling accident and found the calculated doses to be less than a small fraction of 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 NRC.
TSOP1185-0324-NL04 Rev 1
Palisades Plant 6
Proposed Amendment - Spent Fuel Pool
- 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 ~ccidents.
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 NRC 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 floor in a ~imilar 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 has been completed which shows that no horizontal support is required to prevent northerly movement of the Region I racks.
The new racks (Region II) are designed so that the floor loading from the racks filled with spent fuel assemblies does not 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 TSOP1185".""0324-NL04 Rev 1
Palisades Plant 7
Proposed Amendment - Spent Fuel Pool 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 assemblies.
Analysis shows the increased storage capacity will not 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 analysis.
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.
(2)
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 Posit-ion 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 severa~ 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 ac<=:ident previously evaluated for Spent Fuel Storage Facilities if operation of the facility is in accordance with the proposed amendment.
(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 modification, 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 TSOP1185-0324-NL04 Rev 1
Palisades Plant 8
Proposed Amendment - Spent Fuel Pool 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.ana'iysis conform with the applicable portions of the codes, standards, and specifications listed in Section 4.2 of the Safety Analysis Report. *rn meeting the acceptance cr~teria for criticality in the spent fuel pool, such that K f£ is always less than 0.95, including uncertainties at a 95/95 pro~atiility 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 were used to cal~ulate the maximum fuel temperature and *the inc.rease in the temperature of the water in the spent fuel pool.
The thermal-hydraulic evaluation used 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 res~lts ~n an increase of the heat load to the ~pent 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 assemblie.s.
The structural considerations 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 fue_l assemblies, or cause criticality concerns.
Thus, the marg~ns of safety are not significantly reduced by the proposed _rerack.
TSOP1185-0324-NL04 Rev 1
In summation, it has been shown that the proposed spent fuel storage facility modifications do not:
9
- 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 significant safety hazard.
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 of 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 ByQ?~Jt!f#.s!!
Energy Supply Services Sworn and subscribed to before me this 16th day of October 1986.
Elaine E Buehrer, Notary Public Jackson County, Michigan My commission expires October 31, 1989