ML20127P219

Application for Amend to License DPR-36,consisting of Proposed TS Change 177 to Allow Increase in Number of Spent Fuel Assemblies Stored in Spent Fuel Pool from 1,476 to 2,019.Rev 0 to Licensing Rept... Encl

ML20127P219
Person / Time
Site:	Maine Yankee
Issue date:	01/25/1993
From:	Frizzle C Maine Yankee
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20127P223	List: ML20127P219 ML20127P247 ML20127P256
References
CDF-93-18, MN-93-09, MN-93-9, NUDOCS 9302010215
Download: ML20127P219 (16)

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w% Proposed Change No. 177  ;

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% ;UNITEDSTATESNUCLEARREGULATORY! COMMISSION  :

Pl@ ' Attention: ' Document Controit Desk-71 -

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References:

l .(a) License'No. DPR-36 (Docket No. 50-309),

_ (b)~. Letter, USNRC to. MYAPCo, " Safety Evaluation- and- -

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,' ; , Environmental Impact Appraisal Regarding Maine Yankee- U g' Spent Fuel Storage", dated June 16,.1992 -

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Subject:

' Proposed Technical: Specification Change No'.177: Maine Yankee

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iThis submittal,: pursuant to .10CFR50.90,"is in. support of an operating

, llicense amendment = request ~ ta allow an increasesin the number-of spent ~ fuel -

assemblies 3 stored-in.the Mait,eiYankee: Spent Fuel Pool from41476 to:2019.' '

The 111 cense: amendmentn request 11s : required to provide' spent fuel ~ storage.

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Attachment:

A: sSignificant Hazards" Evaluation.

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s JAttachment-B: .: Summary; Description of the1 Proposed bi * ._ .., . _ . eTechnicaliSpecification Changes _

~ _ ! Attachment C: ~ : Proposed 1Technicali Specification Changes:

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• tAttachment D:?: Comparison of;Significant-DesigniAttributes.

(and Analytical' Methodologies to!Previously'-

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-Approved.: Applications .. ..

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,  ; Attachment;E::: Licensing; Report:sSpentTFuelLPool Reracking-

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' UNITED STATES NUCLEAR REGULATORY COMMISSION MN-93-09 ATTENTION:: DOCUMENT CONTROL DESK Page Two' Under this proposed reracking, the ability to store an increased number spent fuel assemblies will be provided by replacing the existing spent fuel ' storage racks, Reference (b), with new higher density spent- 1 fuel storage racks in the spent fuel pool. These new racks are analogous to other licensed designs (see Attachment D) and provide for conventional storage of spent fuel in a single tier, rectilinear array of free standing modules that is compatible with existing fuel handling equipment, procedures, and techniques at Maine Yankee. -The new racks will be installed such that the resultant spent fuel pool becomes a two region (I and II) arrangement. Region I racks are designed to. accommodate any fuel placed in the spent fuel pool regardless of initial enrichment (up to 4.5%) or burnup level. Region Il rack usage will be limited to fuel with a specified burnup level achieved. Both rack designs utilize the standard spent fuel storage rack materials of Boral" (neutron absorber) and 304L stainless steel (structural components).

The proposed new spent fuel storage racks are designed in accordance y with the guidance provided by Sections 9.1.2 and 3.8.4 of NUREG 0800, >

USNRC Regulatory Guides 1.29 and 1.92, the 1978 USNRC position paper on Spent Fuel Storage applications, and Seismic Category I requirements.- All design, procurement, fabrication, and installation activities are being performed in compliance with 10CFR50, Appendix B, Quality Assurance x requirements.

Additional design criteria and technical details, along with the safety analysis and environmental assessment, are provided via Attachment l E.

Maine Yankee has evaluated the proposed chnges and has determined that these proposed changes do not involve a significant hazards consideration as defined in 10 CFR 50.92. This evaluation is included as ,!

Attachment A.

In - order. to implement this proposed reracking and to update the Facility Operating License, Maine Yankee has provided revisions to-those portions of the Technical Specifications which are affected by this change. A summary description of the proposed changes is provided in Attachment B. These proposed Technical Specification paces-are provided as Attachment C.

The proposed change has been reviewed by the Plant Operation Review Committee. The Committee has concluded that the proposed Technical Specification changes do not constitute an unreviewed safety question.

The Nuclear Safety Audit and Review Committee has also performed an independent review of the proposed change as per the requirements of the i Maine Yankee Technical Specifications.

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'VNITED STATES NUCLEAR REGULATORY COMMISSION MN-93-09 ATTENTION: DOCUMENT CONTROL DESK: Page Three The State of Maine is being notified of this proposed change by copy of this letter.

Very truly yours, e l Charles D. Frizzle President and Chief Executive Officer CDF/ jag Attachment A: Significant Hazards Evaluation Attachment B: Summary Description of the Proposed Technical Specification Changes Attachment C: Proposed Technical Specification Changes Attachment D: Comparison of Significant Design Attributes and Analytical Methodologies to Previously Approved Applications Attachment E: Licensing Report: Spent fuel Pool Reracking c: Mr. Thomas T. Martin (Copy 10)

Mr. E. H. Trottier (Copy 11)

Mr. Charles S. Marschall (Copy 12)

Mr. Paul Stern, Esq. (Copy 13)

Mr. Clough Toppan (Copy 14)

Mr. Patrick J. Dostie (Copy 15)

Mr. Uldis Vanags (Copy 16)

Mr. Thomas G. Dignan, Esq.-(Copy 17)

Mr. R. S. Frank, Esq. (Copy 18)

STATE OF MAINE Then personally _ appeared before me, Charles D. Frizzle, who being duly sworn did state that he is President and Chief Executive Officer of Maine Yankee Atomic Power Company,- that he. is duly authorized to execute and file the foregoing submittal in the name and on behalf of Maine Yank,e Atceic Power Company, and that the statements therein are true to the best of his nowledge and belt f.

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10CFR50.92(c) Evaluation of_Jaine Yankee Soent Fuel Pool Rerackina Introduction Maine Yankee Atomic Power Station is a Pressurized Water Reactor owned and operated I by the Maine Yankee Atomic Power Company of Augusta, Maine. The plant is located in Wiscasset, Maine. The plant has a Combustion Engineering Nuclear Steam Supply System and the reactor core consists of 217 fuel assemblies. A normal core discharge for refueling consists of between 68 and 72 fuel assemblies.

The Maine Yankee spent fuel is stored in the plant's fuel building in a water-filled fuel storage pool. The fuel storage pool is a reinforced concrete box structure founded on bedrock with six foot thick walls and floor. The pool is lined with water-tight, 0.25 inch thick stainless steel plate and its inside dimensions are approximately 39 feet deep by 37 feet wide by 41.5 feet long. Currently, the plant

! is licensed to store 1,476 spent fuel assemblies in a ' single region rack configuration. Maine _ Yankee Atomic Power Company is proposing a revision of the existing spent fuel storage rack configuration to a two-region pool, and an increase in the storage capacity to a maximum of 2,019 fuel assemblies. The Region I capacity

> will be 228 assemblies and the Region 11 capacity will be 1,791 assemblies. Region I is designed to accept fresh fuel with up to 4.5 weight percent U235 enrichment and Region 11 is designed to accept fuel with the same reactivity and a minimum burnup of 30,000 MWD /MTU.

The new racks are a single tier, rectilinear array of free-standing modules. The top elevation of the new racks will be the same as that of the existing racks. The rack structure is of austenitic stainless steel ell-welded construction. The basic component of both Region I and Region II racks is a square tube- (or cell) with i neutron absot Ser material in the form of BORAL"' strips applied to the exterior walls and covered by a protective stainless steel sheathing. For the Region I racks, the cells are spaced at 10.5 inches center-to-center. For the Region II racks, the cells are spaced 9.085 inches center-to-center on alternating rows within a single rack with the cells connected on their corners. The fuel is stored in both the cells and in the " virtual cells" formed between the cells.

The new fuel racks will not require any change in the existing fuel handling equipment and techniques at the Maine Yankee Plant. The design of the new spent fuel storage racks utilizes previously licensed concepts and allows for the most efficient-use of available fuel storage areas within the fuel pool. Industry standard design concepts, fabrication techniques, and installation methods are employed. The spent fuel racks are classified as safety-related, and therefore, design, material procurement, fabrication and installation are subject to the Quality Assurance Program requirements of Appendix B to 10CFR50.

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9 Evaluation of Sianificant Hazards Considerations -

Maine YankeeL Atomic Power Company presents this evaluation of the hazards

- consideration involved with the proposed reracking of the spent fuel pool focusing-on the standard set forth in 10CFR50.92(c):

The Commission may make a final determination, pursuant to the procedures in 50.91, that a proposed amendment to an operating license for a facility licensed under 50.21(b) or 50.22 or for a , testing facility involves no significant hazards consideration, if operation of the facility in accordance with the proposed amendment would 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 nf safety.

Maine Yankee Atomic Power Company believes tha_t operation of _ Maine Yankee in-accordance with the proposed spent fuel pool reracking license amendment will not create the possibility of any new accident, increase the probability or consequences of any previously evaluated accident, nor significantly reduce any margin of safety.

- Thus, Maine Yankee Atomic Power Company has concluded that this proposed license amendment involves no significant. hazards consideration as _dafined in 10CFR50.92(c).

In support of this determination, a discussion' of each of the significant safety _

hazards censideration factors with respect to the proposed action is provided.

(1) Does the prooosal involve a sianificant increase in the erobability or consecuences of an accident oreviously evaluated?

The proposed spent fuel pool modification has been analyzed for the impact.on.

30stulated accident scenarios currently addressed in the Maine Yankee licensing aasis including:

(a) Installation (i.e., removal of existing racks and installation of the new racks);

(b) Criticality (i.e., spent fuel assembly misplacement _in the spent fuel pool on top of the racks or alongside the racks);

(c) Thermal-Hydraulic (i.e., partial loss of spent fuel pool cooling system circulation : flow, complete loss of circulation flow and/or cooling, partial loss of spent fuel. pool water inventory); and (d) Fuel handling (i.e., impact of dropping a spent fuel assembly).

The effects of these potential accident scenarios have been fully _ analyzed in the Maine Yankee Spent Fuel _ Pool Reracking Licensing. Report. These analyses demonstrate that the consequences of postulated accidents remain within the current licensing basis for. Maine Yankee.

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l The probability of any of the last three accidents is not affected by the racks themselves; thus, reracking does not increase the probability of these accidents.

With respect to a possible installation accident, all work in the spent fuel pool area will be controlled and performed in strict accordance with specific written procedures which satisfy all applicable regulatory criteria. These controls will be at least as rigorous as those used in the previous two rerackings of the Maine Yankee Spent fuel Pool and, therefore, the probability of e.n installation accident is not significantly increased. Additionally, an installation accident involving damage to spent fuel is precluded by adherence to the prohibition of lifting empty I acks over the stored fuel.

Additional discussion of each accident category follows:

(a) Installation The heavy load handling equipment cilized in reracking will consist of the Fuel Building Overhead Crane (Yard Crane) and a temporary crane that 4

spans the storage pool. The function of the temporary crane is to move storage racks to areas located outside of the range of travel of the Fuel Building Overnead Crane hook. All equipment designs and operations involving heavy lifts and the use of heavy lift equipment in the spent fuel pool area will be governed by the applicable guidance in NUREG-0800, NUREG-0612, NUREG-0554, and ANSI 14.6 and controlled in accordance with the Maine Yankee Heavy Loads Program.

Although the 125/20 ton Yard Crane will be overhauled and refurbished prior to the reracking, its use will be limited to 25% of its capacity, or a maximum of 30 tons, to provide additional margin of safety during the reracking process and to ensure compliance with NUREG 0554 and 0612. To minimize the consequences of a load drop the following precautionary measures will be taken: (1) fuel will be removed from the storage rack before the rack is moved, (2) a clear travel path will be established for the rack being moved (i.e., no lifts over fuel and minimum possibilities for rack-to-rack and rack-to-wall impacts), (3) using the temporary crane and four point rigging, the rack will be lifted clear of the pool floor (carrying height not to exceed 12 inches) and transported to a lay-down area within the pool that is within the range of travel of the fuel Building Overhead Crane hook, and (4) four point rigging meeting the requirements of Section 5.1.6(1) of NUREG-0612 and a combination of the temporary crane and the fuel Building Overhead Crane will be used to lift and transport the storage rack out of the pool and deposit it in the Radiation Control Area (RCA) Building. The old racks will be hydrolazed underwater as they exit the fuel pool, dried, bagged and placed into shipping containers for transport to a licensed decontamination facility.

The new racks will be installed in the pool by reversing the sequence of the steps taken to remove the existing racks. Because the new racks make more efficient use of the pool space, additional storage space will become available as the existing racks are replaced. Consistent with - the requirements of Maine Yankee Technical Specification 3.13, fuel storage racks may be moved only in accordance with written procedures which ensure that no rack modules are moved over fuel assemblies.

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Because the performance and preparation requirements for both personnel and equipment utilized in the rack removal and installation activities will-be at least as rigorous as for _the two previous reracking efforts, Maine Yankee concludes that there will be no -increase in either the probability or the consequences of an installation accident.

(b) Criticality Maine Ymkee Atomic Power Company has considered the. effects of vafious accidents on the reactivity of the spent fuel in the pool. -_These include the effect of misplacing an assembly on top of the racks or alongside the-racks. In all of these events, credit may be taken for the presence of soluble boron in the pool. Maine Yankee Technical Specifications 1.1,--

Fuel Storage, require that the s 'ent fuel pool be maintained at the refueling water boron concentration. This concentration matches that in the reactor cavity and refueling canal during refueling operations. At this concentration the effective multiplication factor of the pool is reduced substantially. Accounting for this presence of soluble boron and-conservatively assuming the racks are fully loaded with fuel, all the acsident configurations analyzed had effective multiplication factors less than 0.95 including all uncertainties. In addition, for certain postulated spent fuel cooling accidents, localized voiding may occur _ in a limited number of storage cells. In all credible cases, the voiding due to these accident conditions would decrease reactivity. Because the-acceptable margin to criticality as indicated by the effective multiplication factor has not changed,-the consequences of a reactivity accident are not significantly increased from those previously evaluated.

(c) Thermal Hydraulic A thermal hydraulic analysis of the spent fuel pool has confirmed that the installation of the new racks will not require any modification to the existing spent fuel pool cooling, makeup, and cleanup systems. This conclusion was anticipated because the pool heat load design parameters have not changed. The thermal hydraulic analysis shows that the highest calculated pool and cell temperatures iemain within the currently licensed -

parameters.

Three sources of fuel pool makeup water are available: (1); the normal makeup via the Chemical Volume Control System (CVCS) which can provide 150 gpm in less than 15 minutes; (2) secondary makeup sources of water via three primary grade water hose connections, each capable of supplying 20 gpm in less than 15 minutes and (3) an emergency makeup source via.the fire main system which is capable of providing 150 gpm in less than 20 minutes.

The analyses show that sufficient time.is available to provide corrective-

! action in the event of a loss of all cooling by . the Spent . Fuel Pool Cooling System (SFPCS). Thus, the consequences of this type of accident are not significantly increased from previously evaluated loss of SFPCS-flow accidents.

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4 (d) Fuel Handlina The dropping of objects over the storage _ array has been analyzed _ for impact on the racks. An extra degree of conservatism has been introduced in the analysis by assuming that the dropped object is twice the weight of-a standard fuel assembly. In the unlikely event of a fuel assembly drop on top of a storage rack, subcriticality and a coolable geometry- are maintained and damage to stored fuel is minimized. Thus, the intended safety function of the racks will continue to be met. Al so, the radiological consequences of a fuel assembly drop are not changed from- ,

those identified in the current Maine Yankee licensing basis.

The current licensing basis for Maine Yankee does not include consideration of the ef fects of a spent fuel shipping cask drop accident.

There are no current plans to use a spent fuei shipping cask in the Maine Yankee fuel storage pool for the foreseeable future. Maine Yankee-has previously committed to make an evaluation for the cask drop accident effects when the option to ship spent fuel off-site becomes available.

Until this evaluation is completed and all related NRC concerns addressed, spent fuel shipping casks will not be lifted over the fuel pool. - This prohibition is currently included in the Maine Yankee Technical Specifications.

(2) Does the Droposal create the possibility of a new or different kind of accident from those previously evaluated?

Maine Yankee has evaluated the proposed reracking in accordance with the guidance of the NRC position paper entitled, "0T 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. In addition, Maine Yank 6e has reviewed previous NRC Safety Evaluation Reports for rerack applications similar to this proposal.

As a result of this evaluation and these reviews, Maine Yankee finds that the proposed reracking does not create the possibility of a new or different kind of accident from any accident previously evaluated for the Maine Yankee Spent Fuel Storage facility.

The- change to a two-region spent fuel pool requires the performance of additional evaluations to ensure that _the criticality criterion is maintained.

These include the evaluation of the limiting criticality condition, i.e.,:

misplacement of an unirradiated fuel assembly of 4.5 weight percent U*

enrichment into a Region 11 storage cell or outside and adjacent to a Region II

- rack module. The evaluation for this case - shows that when the . boron concentration meets the Technical Specifications requirement, the criticality-criterion is satisfied and the accident is bounded by the previously analyzed assembly misplacement accident. - Although the change to a two-region pool requires the consideration of additional aspects of an assembly misplacement' accident, it does not create the possibility of a new or different kind of-accident from that previously evaluated.

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The conclusions of Haine Yankee are in conformity with the analyses performed by and under the direction of the NRC staff. Prior -to issuance of the final rule concerning procedures and standards for no significant hazards considerations, the NRC directed the staff to prepare a report which would: (1) examine the agency's experience concerning spent fuel pool expansion reviews and (2) provide a technical judgment on the basis for which various methods to expand spent fuel pools may or may not pose significant hazards considerations.

The staff contracted with Science Applications, Inc. (SAI) to perform an evaluation of whether increased storage of spent fuel could pose significant hazards considerations in light of the guidance in the interim final rules. SAI provided a report entitled, " Review and Evaluation of Spent fuel Pool Expansion Potential Hazards Considerations", sal-84-221-WA Rev.1 (July 29,1983). On the basis of that report, the staff informed the Commission in SECY-83-337 (August 15,1983) of the results of its study and included the SAI report.

Maine Yankee believes the results of the NRC staff and SAI studies are particularly noteworthy in that they represent the evaluations of ninety-six different applications to rerack spent fuel pools. As reported in the Federal Register, Volume 51, No. 44, Page 7754, key conclusions resulting from this work include:

(a) "reracking to allow closer spacing of fuel assemblies does not significantly increase the probabilities or consequences of accidents previously analyzed;"

(b) "neither the staff nor SAI have identified significant reductions in-safety margins due to increasing the storage capacity of spent fuel pools;" and finally, (c) "the staff as well as SAI have not identified any new categories or types of accidents as a result of reracking to allow closer spacing for the fuel assemblies."

(3) Does the proo;osal involve a sionificant reduction in a maroin of safety?

The ' safety function of the spent fuel pool and the racks is to preclude criticality or an uncontrolled release of fission products by means of a safe, specially designed, underwater storage location for spent fuel assemblies which require shielding and cooling during storage and handling. The NRC Staff has established that the issue of margin of safety, when applied to spent fuel reracking modifications, should address the-following criteria: (1) nuclear criticality considerations; (2) tnermal-hydraulic considerations; and (3) mechanical, material and structural considerations.

The proposed change to_ add new racks will not significantly reduce the margin of safety for nuclear criticality, since criticality calculations show that the maximum effective multiplication factor- (k,,,) is within the NRC acceptance criterion. The margin of safety applicable to the racks (i.e., k,,,30.95, under all normal and postulated accident conditions given conservative -assumptions) remains unchanged. In addition to conservative calculational assumptions, the maximum calculated k ,, includes sufficient margin for uncertainty in calculational method and mechanical tolerances to assure that k,,, will be s0.95 with a 95 percent probability at a 95 percent confidence level.

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l Conservative methods and assumptions are used to calculate the maximum fuel, cladding, and local water temperatures in the spent fuel pool under expected off-load scenarios. The thermal-hydraulic evaluation uses a conservative mathematical model to demonstrate that the temperature margins of safety are maintained. Existing procedures restrict the total heat load in the pool to less than the spent fuel pool cooling system design limit such that the evaluation results show that the existing spent fuel pool cooling system will maintain the bulk pool water temperature below 154*F for normal discharge and for full core off-load. The maximum local water temperature along the hottest fuel assembly continues to be below the nucleate boiling condition. Thus, there is no reduction in the margin of safety for thermal-hydraulic or spent fuel cooling concerns.

The structural / mechanical design has been analyzed for normal and abnormal conditions, including earthquake, spent fuel assembly drop, rack-to-rack loading, rack-to-spent fuel pool loading, etc. The new racks are Seismic Category I equipment and designed to remain functional during the Safe Shutdown Earthquake (SSE), as specified by NRC Regulatory Guide 1.29. Analyses show that the racks will perform their intended function under both seismic and load drop loadings in accordance with NRC Regulatory Guide 1.124 and NUREG-0800. The rack materials used are compatible with the spent fuel pool and spent fuel assemblies, and were chosen so as to preclude degradation due to material incompatibility (e.g., galvanic corrosion). Thus, the margin of safety is not reduced by the proposed addition of rack modules.

Summary As demonstrated above, the proposed fuel pool reracking does not: (1) 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, or (3) involve a significant reduction in a margin of safety. The proposed reracking is bounded by the licensing basis of the existing fuel racks. The proposed reracking meets the NRC's criteria for a reracking not likely to involve a significant hazards consideration. For these reasons, Maine Yankee believes that- the proposed reracking of the fuel pool does not involve a significant hazards consideration as defined by 10CFR50.92(c).

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Additional NRC Guidance Concernina No Sianificant Hazards Considerations The NRC has published " Examples of Amendments That Are Considered Net Likely to

-Involve Significant Hazards Considerations" in the final NRC adoption of 10CFR50.92 on Page 7751 of the Federal Register Volume 51, No. 44, March 8,1986. Example X of that list, which derives from the previously referenced NRC staff and SAI studies of reracking proposals, is applicable to the proposed Maine Yankee spent fuel pool reracking.

The example states:

(X) An expansion of the storage capacity of a spent fuel pool is considered not likely to involve significant hazards considerations when all of the following criteria are satisfied:

Criterion (1)

The storage expansion method consists of either replacing existing racks with a design which allows closer spacing between stored spent fuel assemblies or placing additional racks of the original design on the pool floor if space permits.

proposed Maine Yankee Rerackina The proposed fuel pool reracking meets Criterion (1). The existing Maine Yankee spent fuel rack configuration, which accommodates 1,476 fuel assemblies, is a single region design with a storage location center-to-center spacing of 10.25 inches. The new racks will provide for a two region configuration with a; maximum total capacity of 2,019 fuel assemblies. For Region I, 228: storage.

locations will be spaced at 10.5 inch centers and for Region II, 1,791 storage locations will be spaced at 9.085 inch centers. The fuel cell arrangement is 2ptimized utilizing a minimum storage cell pitch with neutron absorbing material (BORAL") positioned to maintain subcriticality limits.

Criterion (21 The storage expansion method does not involve rod consolidation or double tiering.

Ergposed Maine Yankee Rerackina The proposed fuel pool reracking meets Criterion (2). The proposed racks are not double-tiered as all racks will' rest on the spent fuel pool floor.

Maine Yankee's current Technical Specifications allow for the storage of up to -

20 fuel assemblies in consolidated form under an NRC approved program. . The-l proposed spent fuel storage rack design . retains the ability to store these -

l consolidated' spent fuel assemblies. The proposed reracking does not involve the consolidation of spent fuel -beyond the previously approved test. program identified in the Maine Yankee Technical Specifications. The proposed reracking-does not alter existing consolidated fuel license conditions nor does it propose new or different consolidation techniques or methods for'use with the new fuel storage racks.

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Criterion (3)

The k,,, of the pool is maintained less than or equal to 0.95.

Proposed Maine Yankee Rerackina The proposed fuel pool reracking meets Criterion (3). The design of tha new spent fuel racks contains a neutron absorber, BORAL", to allow close storage of spent fuel assemblies while ensuring that the k.,, remains less than 0.95 under all normal and postulated accident conditions.

Criterion (4)

No new technology or unproven technology is utilized in either the construction process or the analytical techniques necessary to justify the expansion. .i Proposed Maine Yankee Rerackina The proposed fuel pool reracking meets Criterion (4). As detailed in the Maine Yankee Spent Fuel Pool Reracking Licensing Report, the proposed reracking utilizes proven technology and analytical techniques in both the design and construction processes.

Thus, the Maine Yankee proposal is completely consistent with the Example '(X) criteria presented in the supplementary information accompanying publication of 10CFR50.92.

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Attachment B Summary Description of the Proposed Technical Specification Chanaes l

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y Summary 1 Description of Proposed TechnicalLSpecification Changes Spent Fuel Storage Modifications

Item: . Technical:

No. Speci fication . Description of Change' -Reason for-Change

1. 1.1.8 Replaced the word "is" with the words Clarification of wording.

(page 1.1-1) "shall be" in the first line.

2. 1.1.C Replaced the word "is" with the words Clarification of wording.

(page 1.1-1) "shall be" in the second line.

3. 1.1.E Revision from 1476 stored assemblies to Consistency between the proposed design inccrporating (page 1.1-1) 2019. Identification of Region I and 2019 storage locations in a two region spent fuel pool Region II storage areas in the spent and the existing Technical Specifications.

fuel pool. Add Figure 1.1-1 identifying limitations between Regions I and II.

Define consolidated fuel storage.

4. 1.1.F Revision from 1476 stored assemblies to Consistency between the proposed design and existing (page 1.1-1) 2019. Restriction of the temporarily Technical Specifications. The restriction on the stored assemblies to the same condition temporarily stored assemblies results from the need so as those suitable for placement in define fuel assembly placement limitations throughout Region 11 racks. the spent fuel pool.

5. 1.1.G Revision from 1476 stored assemblies to Consistency between the proposed design and existing (page 1.1-1) 2019. Technical Specification.

, 6. 1.1 Basis Revised text to include consideration of Current Technical Specification Basis does not include (page 1.1-1) proposed design to the Technical this information.

Specifications. Included references to the proposed Spent Fuel Pool Reracking Report and NRC SER.

7.-- Figure 1.1-1 Added figure identifying limits and Provide consistency between proposed design and '

-(page 1.1-3) restrictions associated with fuel Technical Specifications.

placement in Region.I or II of the spent fuel pool. ,

uu .ewan .15 1

Summary' Description of Proposed Technical Specification nges Spent Fuel Storage Modifications yltem' Technical No. Specification. Description of Changel Reason for Change

8. 3.13.B Revised LCO for movement of irradiated The increase in time prior to the movement of (page 3.13-1) fuel from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 144 hours0.00167 days <br />0.04 hours <br />2.380952e-4 weeks <br />5.4792e-5 months <br />. irradiated fuel allows for a lower heat load in the spent fuel pool while also reducing the overall risk associated with refueling operation. (Refer: Maine Yankee Outage Risk Management Program dated 12/91).

9. 3.13.F Revised LCO for the decay time of The increase in time ensures that the placement of (page 3.13-3). consolidated fuel from 120 days to 730 consolidated fuel in Region II rack locations is days. Clarified wording. thermally bounded by the limiting spent fuel assembly.

10. 3.13 Basis Revised basis to include consideration Current Technical Specification Basis does not include

.(page 3.13-4) of the 144 hour0.00167 days <br />0.04 hours <br />2.380952e-4 weeks <br />5.4792e-5 months <br /> and 730 day decay times this information.

identified in the proposed Technical Specifications.

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